Effect of the “Recruitment” Maneuver on Respiratory Mechanics in Laparoscopic Sleeve Gastrectomy Surgery

Effect of the “Recruitment” Maneuver on Respiratory Mechanics in Laparoscopic Sleeve... Purpose LSG surgery is used for surgical treatment of morbid obesity. Obesity, anesthesia, and pneumoperitoneum cause reduced pulmoner functions and a tendency for atelectasis. The alveolar “recruitment” maneuver (RM) keeps airway pressure high, opening alveoli, and increasing arterial oxygenation. The aim of our study is to research the effect on respiratory mechanics and arterial blood gases of performing the RM in LSG surgery. Materials and Methods Sixty patients undergoing LSG surgery were divided into two groups (n = 30) Patients in group R had the RM performed 5 min after desufflation with 100% oxygen, 40 cmH O pressure for 40 s. Group C had standard mechanical ventilation. Assessments of respiratory mechanics and arterial blood gases were made in the 10th min after induction (T1), 10th min after insufflation (T2), 5th min after desufflation (T3), and 15th min after desufflation (T4). Arterial blood gases were assessed in the 30th min (T5) in the postoperative recovery unit. Results In group R, values at T5, PaO were significantly high, while PaCO were significantly low compared with group C. 2 2 Compliance in both groups reduced with pneumoperitoneum. At T4, the compliance in the recruitment group was higher. In both groups, there was an increase in PIP with pneumoperitoneum and after desufflation this was identified to reduce to levels before pneumoperitoneum. Conclusion Adding the RM to PEEP administration for morbidly obese patients undergoing LSG surgery is considered to be effective in improving respiratory mechanics and arterial blood gas values and can be used safely. . . Keywords Laparoscopic sleeve gastrectomy Recruitment maneuver PEEP Purpose Obesity is defined as abnormal and excessive fat accumulation * Ismail Sümer isumer@bezmialem.edu.tr at levels to disrupt health [1]. Lifestyle changes like diet and exercise and medical treatment, in addition to surgical inter- ventions, are frequently used for treatment of obesity [2]. Department of Anesthesiology and Reanimation, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkey Laparoscopic sleeve gastrectomy (LSG) is a new approach for surgical treatment of morbid obesity [3]. With the increase Health Cares Vocational School, İstanbul Esenyurt University, Istanbul, Turkey in surgical interventions for obesity treatment, it is necessary to take more care for anesthesia management of these patients İstanbul Acıbadem Taksim Hospital, Istanbul, Turkey [4]. Obese patients have increased possibility of difficult intu- Department of Anesthesiology and Reanimation, Faculty of bation, in addition to displaying more unwanted effects on the Medicine, İstanbul Medipol University, Istanbul, Turkey respiratory system, compared with normal patients [5, 6]. Department of Anesthesiology and Reanimation, Faculty of Obesity is an important respiratory risk factor as it causes Medicine, Marmara University, Istanbul, Turkey 6 reduced functional residual capacity, compliance and oxygen- Department of General Surgery, Faculty of Medicine, Bezmialem ation in terms of respiratory functions before and after both Vakif University, Istanbul, Turkey 7 surgery and anesthesia, in addition to causing a tendency for Department of Anesthesiology and Reanimation, Cerrahpasa Faculty atelectasis [7, 8]. Reduced functional residual capacity causes of Medicine, İstanbul University Cerrahpasa, Istanbul, Turkey OBES SURG airway closure in situations with delayed endotracheal intuba- Healthcare, Finland), which one uses Fourier transform anal- tion and obese patients in the supine position become rapidly ysis of electroencephalographic data. Neuromuscular block- desaturated. Additionally, dyspnea, exercise intolerance, and ade was monitored from the adductor pollicis muscle inner- obstructive sleep apnea should be carefully questioned [9]. vated by the ulnar nerve with E-NMT-00 (GE Healthcare, Intraperitoneal administration of carbon dioxide (CO )gas Finland) device. Hemodynamic parameters of patients (sys- for laparoscopic surgeries frequently increases intraabdominal tolic, diastolic and mean arterial pressure, heart rate), BIS, pressure, pushing the diaphragm upwards and causing com- SpO , and TOF values were recorded perioperatively with pression of the lungs. The lungs which are already susceptible 5 min interval. to atelectasis due to general anesthesia experience increased Corrected weight calculations were performed for all severity of this effect during laparoscopy [10]. The ameliora- patients; medications and ventilatory settings were adjust- tion of atelectasis developing during general anesthesia for ed according to this calculation. For anesthesia induction, −1 −1 obese patients is slower after the operation compared with propofol 2 mg kg and rocuronium 0.6 mg kg were −1 −1 nonobese patients. Atelectasis is fully resorbed 24 h after the administered and infusions of propofol 10 mg kg hr −1 −1 end of the surgical procedure for nonobese patients, while and remifentanil 0.25 μgkg min were started. All pa- atelectasis was shown to continue in obese patients at this tients had orotracheal intubation and mechanical ventila- −1 point [11]. One of the most important aims of anesthesia man- tion with tidal volume of 6 mL kg , PEEP of 8 cmH O, −1 agement during operations on obese patients is to keep the inspired oxygen (FiO ) 40%, fresh gas flow of 4 L min airway and alveoli open during respiration [12]. The tech- and the ventilatory frequency was adjusted to keep end- niques of keeping airway pressure high for a duration to open tidal carbon dioxide (EtCO ) level between 30 and atelectatic areas with the “recruitment maneuver” (RM) and 35 mmHg. For anesthesia maintenance, propofol infusion positive expiration end pressure (PEEP) may reduce atelecta- wasadjustedtokeepBIS values between 40 and60and sis and increase oxygenation [13]. remifentanil infusion was adjusted to keep hemodynamic The primary aim of this study is to investigate the effect of parameters ± 20 of initial values. Rocuronium was added to RM on postoperative arterial oxygenation after LSG in obese keep train-of-four (TOF) response zero. patients. Our secondary aim was to investigate the effects of During the operation, all patients received 5– −1 −1 RV on perioperative respiratory mechanics. 8mLkg hr balanced electrolyte solution (isolyte-S) infu- sion. After Allen test was performed, radial artery was cannu- lated, and arterial pressure was monitorized. Arterial blood Materials and Methods gases (pH, pO , pCO , HCO , lactate) were analyzed with 2 2 3 RAPIDLab 1200 Systems (Siemens Healthcare GmbH, This study received ethics committee permission from Federal Republic of Germany). From the start of mechanical Bezmialem Vakıf University Faculty of Medicine dated ventilation, respiratory mechanics of compliance, peak inspi- 21.05.2014 numbered 71306642/050-01-04/127. The study ration pressure (PIP), plateau airway pressure (Pplateau), and included patients aged 18–65 years, American Society of airway resistance (Raw) were monitored with a spirometry Anesthesiologists (ASA) III, Body Mass Index (BMI) 40–55 device (E-COVX–Spirometry–00, GE Healthcare, Finland). undergoing elective LSG surgery after informing them about Patients who met the inclusion criteria were divided into the effects of RM performed after desufflation. Written in- two groups; one who received RM (group R, n =30) and the formed consent was obtained from all individual participants control group (group C, n = 30) without RM in a 1:1 random- included in the study. ized closed envelope manner (reviewer no. 1). Recruitment Patients with emergency operation planned, with situations maneuver applied under 100% oxygen, with 40 cmH Oair- representing contraindications to performing the RM (e.g., way pressure for 40 s duration. Patients in group R received bullous lung disease, hemodynamic instability), with respira- RM one time, 5 min after desufflation of the pneumoperito- tory and heart diseases, and using medications that affect re- neum, after RM FiO was adjusted to 40% again. If hemody- spiratory functions like salbutamol, budesonide, and namic instability and hypoxia developed, the RM was formoterol were excluded from the study. stopped. In both groups, arterial blood gas samples were ob- After routine preoperative preparation, patients with oral tained 10 min after induction (T1), 10 min after insufflation intake limited for a sufficient duration had a cannula inserted (T2), 5 min after desufflation (T3), and 15 min after in the vein on the back of the hand in the preparation room desufflation (T4) while respiratory mechanic measurements before the procedure. Premedication was not administered. (compliance, PIP, Pplateau, Raw) were recorded simulta- Patients were monitored in the operating room with a three- neously. Patients were not disconnected from the respiratory channel electrocardiogram (ECG), peripheral oxygen satura- cycle until extubation. Additionally, 30 min after extubation tion (SpO ), noninvasive blood pressure (NIBP), to estimate (T5), blood gas assessment was performed in the recovery the depth of sedation bispectral index (BIS) (E-BIS-00, GE unit. OBES SURG −1 All patients received 2 mg kg sugammadex and were weight, anesthesia duration, and surgical duration between extubated under 40% FiO when neuromuscular monitoring the groups (Table 1). TOF ratio was ≥ 0.9. In the recovery unit, all patients received There was no statistically significant difference between −1 5 L min oxygen through a face mask. For postoperative the pH values in the control and recruitment groups at T1, analgesia, 100 mg tramadol was administered 10 min before T2, T3, T4, and T5 measurements. In both groups, the pH the end of the operation and local anesthetic infiltration values measured at T1, T2, T3, T4, and T5 were statistically (bupivacaine 0.5%) was administered to the trocar entry significantly different (p < 0.001 for both groups with the points at the end of surgery. Friedman test). In both groups, blood gas pH values at T2, T3, T4, and T5 were statistically significantly low compared with the pH at T1 (p < 0.001 for all analyses with Wilcoxon Statistical Analysis signed ranks test) (Table 2 and Fig. 1). There was no statistically significant difference between The data obtained were statistically analyzed. When analyzing the groups in terms of PaO values at T1, T2, T3, and T4 findings obtained in the study, the IBM SPSS version 20 (IBM (p =0.352, p =0.092, p =0.34, p = 0.169, respectively). SPSS, Turkey) program was used for statistical analysis. A However, when the T5 value is examined, the PaO value in statistical power analysis was performed for sample size esti- group R was statistically significantly high compared with the mation, based on data from published study, Whalen et al. PaO value in group C (p = 0.017, Mann-Whitney U test) [14]. In the present study, effect size was estimated as 0.77, (Table 2 and Fig. 1). alpha was defined as 0.05, and power as 0.90, the projected When both groups are compared within themselves, the sample size needed with this effect size (GPower 3.1) is ap- PaO values at T1, T2, T3, T4, and T5 were statistically sig- proximately N = 58. A total of 29 patients would be required nificantly different (p = 0.008 for group C, p <0.001 forgroup in each group for this simplest between group comparisons. R, Friedman test). The difference observed in group C was When assessing study data, fit of parameters to normal distri- due to the T3 PaO value being statistically significantly high bution was evaluated with the Shapiro-Wilk test. When compared with the T1 PaO value (p = 0.004, Wilcoxon assessing study data, descriptive statistical methods (mean, signed ranks test). In group C, the T4 PaO value was not standard deviation, frequency) were used. For comparison of statistically significantly different from the T1, T2, and T3 quantitative data with parameters showing normal distribu- PaO values (p > 0.05, Wilcoxon signed ranks test). In group tion, two groups were compared with the student t test, while R, the T4 PaO value was statistically significantly high com- comparison of two groups without normal distribution used pared with the T1, T2, and T3 values (p =0.001, p <0.001, the Mann-Whitney U test. Analysis of more than two mea- p = 0.001, respectively), Wilcoxon signed ranks test (Table 2 surements obtained in a single group for values without nor- and Fig. 1). mal distribution used the Friedman test. Significance was At T1, T2, T3, and T4 measurements, there was no statis- assessed at p < 0.05 level. After the Friedman test, two-way tically significant difference between the groups in terms of comparisons of within-group measurements used the PaCO values (p =0.141, p =0.605, p =0.075, and p =0.107, Wilcoxon signed ranks test to identify the difference. For respectively). However, when the T5 value is examined, the blood gas measurements, significance for 5 measurements with a total of 10 two-way comparisons was evaluated at the p < 0.005 level and for respiratory mechanics, significance for Table 1 Demographic data, surgical duration, and anesthesia duration 4 measurements with a total of 6 two-way comparisons was in the groups evaluated at p < 0.008 level. Group C (n = 30) Group R (n =30) P Age (years) 38.7 ± 11.2 37.8 ± 9.7 0.74 Results Sex (F/M) 26/4 26/4 Weight (kg) 120.3 ± 17 127.97 ± 17 0.087 The study included 60 patients undergoing LSG surgery for Height (cm) 163 ± 7.7 165 ± 8.3 0.33 morbid obesity from 01.06.2014 to 01.02.2015. The mean age −2 BMI (kg m ) 45.4 ± 4.1 47.2 ± 4.6 0.12 of all patients included in the study was 38.25 ± 10.37 years. Corrected weight (kg) 81.1 ± 11 85.4 ± 11.2 0.135 There were 30 patients each in group C and group R. The sex Ideal weight (kg) 55.2 ± 8 56.8 ± 9 0.49 distribution was equal in the groups of patients included in the Anesthesia duration (min) 124 ± 18.7 130 ± 19 0.232 study. Patients did not develop any hemodynamic complica- Surgery duration (min) 88.1 ± 19.2 93 ± 19 0.322 tions. No patient required intensive care. There were no statistically significant differences between BMI, body mass index. Values given as mean ± standard deviation or patient numbers. Student t test was used the mean age, weight, height, BMI, calculated corrected OBES SURG Table 2 Analysis of pH, PaO PaCO and HCO values in the groups 2, 2, 3 T1 T2 T3 T4 T5 pH Group C (n = 30) 7.42 ± 0.04 7.37 ± 0.04 7.36 ± 0.04 7.37 ± 0.04 7.40 ± 0.05 Group R (n = 30) 7.42 ± 0.03 7.36 ± 0.03 7.34 ± 0.05 7.36 ± 0.04 7.39 ± 0.03 P 0.800 0.830 0.337 0.327 0.800 PaO (mmHg) Group C (n = 30) 163.3 ± 52.5 173.9 ± 47 177.6 ± 44.2 177 ± 62.2 151.7 ± 39 Group R (n = 30) 150.1 ± 55.7 153.4 ± 48.2 166.2 ± 47.9 211.5 ± 77.1 177.4 ± 37.9 P 0.352 0.092 0.340 0.169 0.017 PaCO2 (mmHg) Group C (n = 30) 40.8 ± 5.9 44.6 ± 4.8 42.7 ± 4.9 40.4 ± 5.7 42.7 ± 4.2 c c c e Group R (n = 30) 39.1 ± 4.1 44.1 ± 3.4 45.2±6 42.4±6 39.9 ± 2.7 P 0.141 0.605 0.075 0.107 0.012 f f f HCO Group C (n = 30) 25.8 ± 2.5 25.4 ± 2.2 24.2 ± 2.5 23.4 ± 2.5 22.8 ± 2.8 Group R (n = 30) 25 ± 2.2 24.9 ± 1.9 24.6 ± 2.4 24 ± 2.3 23.8 ± 1.9 P 0.158 0.375 0.559 0.308 0.096 PaO , arterial oxygen pressure; PaCO , arterial carbon dioxide pressure; HCO , bicarbonate value. Values give as mean ± standard deviation. 2 2 3 Comparisons between groups used Mann-Whitney U test; comparisons within groups used Wilcoxon signed ranks test Comparison between groups is statistically significant Within groups, comparisons with T2, T3, T4, and T5 are statistically significant Within groups, comparisons with T1 are statistically significant Within groups, comparisons with T1, T2, and T3 are statistically significant Within groups, comparisons with T2 and T3 are statistically significant Within groups, comparisons with T1 and T2 are statistically significant PaCO value in group R was statistically significantly low The PaCO values measured at T1, T2, T3, T4, and T5 2 2 compared with the PaCO value in group C (p =0.012, were statistically significantly different within both groups Mann-Whitney U test) (Table 2 and Fig. 1). (p < 0.001 for both groups, Friedman test). In group C, this 220,0 211,5 pH PaO (mmHg) PaCO (mmHg) 2 2 46,0 200,0 45,2 44,6 7,45 177,6 44,0 173,9 7,42 180,0 177,4 42,7 177,0 44,1 42,7 7,4 7,42 42,4 7,40 163,3 42,0 7,39 7,37 160,0 7,37 7,36 166,2 40,8 151,7 7,36 150,1 7,35 7,36 40,0 39,9 153,4 40,4 140,0 39,1 7,34 38,0 7,3 120,0 T1 T2 T3 T4 T5 T1 T2 T3 T4 T5 36,0 T1 T2 T3 T4 T5 C R C R C R -1 -1 HCO (mmol.L ) Lactate (mmol.L ) SpO 1,06 1,1 99,6 99,6 27,0 100,0 0,97 98,8 99,1 26,0 1 25,4 25,8 99,0 98,2 99,4 24,6 25,0 25,0 99,0 99,1 0,95 24,0 0,86 0,86 24,9 0,9 98,0 24,0 23,8 24,2 97,8 0,82 98,0 23,0 22,8 97,0 23,4 0,77 0,8 22,0 0,82 0,79 96,0 21,0 T1 T2 T3 T4 T5 T1 T2 T3 T4 T5 0,7 T1 T2 T3 T4 T5 C R C R C R Fig. 1 Graphs of pH, PaO PaCO HCO and SpO variations in groups 2, 2, 3, 2 OBES SURG difference was due to the T2 PaCO value being statistically statistically significantly low compared with the T1 and T2 significantly high compared with the T1 PaCO value measurements (p <0.001, p < 0.001, Wilcoxon signed ranks (p < 0.001, Wilcoxon signed ranks test). In group R, the T2, test). In group R, this difference was due to the T3 Raw value T3, and T4 measurements were statistically significantly high being statistically significantly low compared with the T1 and compared with the T1 measurements (p < 0.001, p < 0.001, T2 Raw values (p =0.002, p = 0.004, respectively) and the T4 p = 0.003, respectively, Wilcoxon signed ranks test). Raw value being statistically significantly low compared with Additionally, the T5 value was statistically significantly low the T1 value (p = 0.002, Wilcoxon signed ranks test) (Table 3 compared with the T1 and T2 values (p <0.001, p =0.001, and Fig. 2). respectively, Wilcoxon signed ranks test) (Table 2 and Fig. 1). There was no statistically significant difference between There was no statistically significant difference between the PIP measurement values in the groups at T1, T2, T3, and the HCO values between the groups at T1, T2, T3, T4, and T4 measurements (Mann-Whitney U test) (Table 3 and Fig. T5 measurements (Mann-Whitney U test) (Table 2 and Fig. 2). 1). Within both groups, the PIP values measured at T1, T2, T3, Within group C, HCO values in blood gas measurements and T4 were statistically significantly different (p < 0.001 for at T1, T2, T3, T4, and T5 were statistically significantly dif- both groups, Friedman test). This difference in both groups ferent (p < 0.001, Friedman test). This difference in group C was due to the T2 PIP value being statistically significantly was due to the T3 HCO value being statistically significantly high compared with the T1, T3, and T4 PIP measurements lower than the T1 and T2 values, (p =0.001, p <0.001, re- (p < 0.001 for all measures in both groups, Wilcoxon signed spectively); the T4 HCO value being statistically significant- ranks test) (Table 3 and Fig. 2). ly low compared with the T1 and T2 values (p < 0.001, The Pplateau values at T1, T2, T3, and T4 measurements in p < 0.001, respectively); and the T5 HCO value being statis- both groups were not statistically significantly different tically significantly low compared with the T1 and T2 values (Mann-Whitney U test) (Table 3 and Fig. 2). (p <0.001, p = 0.001, respectively, Wilcoxon signed ranks Within both groups, the T1, T2, T3, and T4 Pplateau values test) (Table 2 and Fig. 1). were statistically significantly different (p < 0.001 in both There was no statistically significant difference between groups, Friedman test). This difference was due to the T2 the lactate values between the groups at T1, T2, T3, T4, and Pplateau value being statistically significantly high compared T5 measurements (Mann-Whitney U test). with the T1, T3, and T4 Pplateau measurements in both There was no statistically significant difference between groups (p < 0.001 for all measures in both groups, Wilcoxon the compliance values in the groups at T1, T2, and T3 mea- signed ranks test) (Table 3 and Fig. 2). surements. However, when the T4 compliance value is exam- ined, the compliance in group R was statistically significantly high compared with the compliance in group C (p =0.043, Discussion Mann-Whitney U test) (Table 2 and Fig. 2). Within both groups, the compliance values measured at T1, There is no guideline with definite rules for ventilation strat- T2, T3, and T4 were statistically significantly different egies in obese patients. However, in the literature, PEEP ap- (p < 0.001, Friedman test). The compliance value measured plied after the recruitment maneuver and less than 80% FiO at T4 in group C was not statistically different from the com- administration methods recommended to maintain physiolog- pliance value measured at T1, while it was significantly higher ical oxygenation [15, 16]. Lung-protective ventilation strategy −1 than the T2 value (p < 0.001, Wilcoxon signed ranks test). In (aproximately 8 ml kg tidal volume and administered using group R, the T4 compliance value was found to be statistically estimated true body weight), PEEP administration, and alve- significantly high compared with the T1, T2, and T3 measure- olar recruitment maneuvers prevent atelectasis and positively ments (p < 0.001 for all, Wilcoxon signed ranks test) (Table 2 affect intraoperative gas exchange which prevents the devel- and Fig. 2). opment of hypoxemia [12, 17]. High PEEP administration There was no statistically significant difference in terms of prevents the decrease in lung volume at the end of expirium the Raw values in the control group and recruitment group at formed by increased intraabdominal pressure and in this way T1, T2, T3, and T4 measurements (Mann-Whitney U test) is reported to have positive effects on respiratory mechanics, (Table 3 and Fig. 2). gas exchange, and PaO values in morbidly obese patients Within both groups, the Raw values measured at T1, T2, [18, 19]. A variety of studies have reported that administration T3, and T4 were statistically significantly different (p <0.001 of PEEP with the RM ensures better oxygenation and compli- for both groups, Friedman test). This difference in group C ance compared with patients with only PEEP applied [20–24]. was due to the T3 Raw value being statistically significantly With the aim of investigating the effects of PEEP and recruit- low compared with the T1 and T2 Raw values (p < 0.001, ment, there are studies performed by CT or MR imaging for p < 0.001); additionally, in group C the T4 Raw value was each patient and evaluated according to the results of these OBES SURG -1 -1 -1 Compliance (ml.cmH O ) RAW (cmH O.lt .sn ) 2 2 50 17 16,6 16,1 40,2 45,6 16,2 15,2 37,4 39 14,4 28,2 34,6 13,1 27,3 13,1 20 12 T1 T2 T3 T4 T1 T2 T3 T4 C R C R PIP (cmH O) Pplateau (cmH O) 2 2 27,6 32 29 30,3 30 27 28 25 30,1 26,1 26,4 24,7 23,4 26 23 21,5 22,5 21,8 26,2 24 21 24,5 20,4 21,3 22 19 T1 T2 T3 T4 T1 T2 T3 T4 C R C R Fig. 2 Graphs of compliance, Raw, PIP, and Pplateau variations in groups imaging methods [25–27]. Two studies by Rothen et al. [26, They reported that 40 cmH O with 5 multiple deep breathing 27] administered at least 40 cmH O pressure for 7–8 s dura- was less effective than only PEEP administration or both used tion and observed that all atelectatic lung tissues opened, there together. In our study, during the operation, PEEP adminis- was a marked reduction in the amount of shunt and oxygena- trated with 8 cmH O at the beginning before insufflation tion significantly improved. Henzler et al. [28]inan animal lasted until the end of the operation, while the RM was per- study performed the recruitment maneuver with 45 cmH O formed 5 min after desufflation with 40 cmH O pressure for 2 2 pressure for 40 s and found the RM provided an increase in 40 s duration. We used 100% oxygen only during the RM and ventilation of weakly ventilated lung volumes. In our study, as part of this maneuver for only 40 s. This is the limitation of we attempted to determine the efficacy of PEEP and RM using our study. Although we used this FiO value, there was no respiratory mechanics values and arterial blood gas measure- difference between the groups in the T4 measurements per- ments due to the cost increase caused by these imaging formed at the 15th min after desufluation. T5 was the 30th min methods and the technical difficulties of performing CT and measurement after extubation and the difference between the MR imaging for obese patients. We used PEEP and the RM two groups appeared in this measurement. This difference was together. Talab et al. [29] stated there was better oxygenation, more relevant with the pressure and duration we used. In fact, less atelectasis, and less postoperative respiratory complica- in one study, recruitment maneuver with low oxygen concen- tions with no barotrauma encountered in the group with tration has been shown to be more effective for oxygenation. 10 cmH O PEEP and 40 cmH O recruitment procedure for [31] We found that the PaO value in the recruitment group 2 2 2 7–8 s. Golparvar et al. [30] performed in their study in 3 was significantly high compared with the control group at T5. groups; multiple deep breathing maneuvers, PEEP, and both. Hemmes et al. [32] administered high PEEP (12 cmH O) to 2 OBES SURG Table 3 Comparison of compliance, raw, PIP, and Pplateau values in groups T1 T2 T3 T4 Compliance Group C (n = 30) 34.6 ± 8.1 27.3 ± 5.6 39 ± 9 37.4 ± 8.2 Group R (n = 30) 35.8 ± 11.3 28.2 ± 6.3 40.2 ± 11.1 45.6±15 P 0.988 0.888 0.941 0.043 −1 −1 d d Raw (cmH Olt sn ) Group C (n = 30) 16.6 ± 5.7 15.2 ± 3.6 13.1 ± 3.2 13.1 ± 3.1 d e Group R (n = 30) 16.2 ± 5.6 16.1 ± 4.4 14 ± 3.6 14.4 ± 4.8 P 0.629 0.474 0.368 0.38 PIP (cmH O) Group C (n = 30) 26.2 ± 4.5 30.3 ± 3.8 24.5 ± 3.3 25 ± 3.3 Group R (n = 30) 26.4 ± 4.2 30.1 ± 3.4 24.7 ± 4.7 24 ± 4.1 P 0.795 0.818 0.97 0.176 Pplateau (cmH O) Group C (n = 30) 22.5 ± 4.7 26.1 ± 5.6 21.3 ± 3 21.8 ± 3.2 Group R (n = 30) 23.4 ± 3.8 27.6 ± 3.5 21.5 ± 4.6 20.4 ± 4 P 0.543 0.338 0.87 0.132 Raw, air way resistance; PIP, peak inspiratory pressure; Pplateau, plateau pressure. Values given as mean ± standard deviation. Comparisons between groups used Mann-Whitney U test; comparisons within groups used Wilcoxon sign test Comparison between groups is statistically significant Within groups, comparisons with T2 are statistically significant Within groups, comparisons with T1, T2, and T3 are statistically significant Within groups, comparisons with T1 and T2 are statistically significant Within groups, comparisons with T1 statistically significant Within groups, comparisons with T1, T3, and T4 are statistically significant obese patients undergoing open abdominal surgery and stated increase, while this value decreases after pneumoperitoneum it was not protective in terms of postoperative pulmonary and we identified that this was significant in the recruitment complications. They stated that for intraoperative protective group. ventilation strategy, it is necessary to ensure low TV and low Sprung et al. [35] reported a 30% reduction in compliance PEEP (2 cmH O) without recruitment. Our study group and 68% increase in Raw in supine position for morbidly underwent laparoscopic surgery and there are studies showing obese patients compared with normal weight patients. In lap- that due to the negative effects on lung dynamics, our patients aroscopic surgery, PIP, Raw, and Pplateau increase, compli- were more susceptible to atelectasis development [7, 8, 10]. ance decreases [35–38]. After desufflation, PIP and Pplateau Findings during open surgery may be different from laparo- decrease andcomplianceincreases; however,it was shown to scopic surgery. As a result, we applied relatively high PEEP be 14% reduced compared with the value before insufflation along with the RM in our study. [38]. It is proposed that the RM performed after desufflation Arterial blood gas analysis are one of the best methods to in laparoscopic surgery is effective to completely regain lung assess pulmonary function. The first parameter examined to compliance [35]. According to the data obtained in our study, assess the acid-base balance is pH [33]. Iwasaka et al. [34] we thinkthe RM performedwithPEEPhas greaterpositive investigated that blood gas analysis during laparoscopic sur- effects on compliance. When Rawis investigated,contrary to gery with increased intraabdominal pressure and CO insuf- previous studies [36], we found Raw reduced during surgery. flation decreases in arterial pH and increases in PaCO values PIP values in both groups increased with insufflation, and we due to CO retention. When we assessed pH, HCO ,and identified they regressed to values before pneumoperitone- 2 3 PaCO data in our study, we did not identify a difference um with desufflation. Based on the findings from Raw and between the two groups for pH values; however, we deter- PIP measurements, we concluded that 8 cmH O PEEP ad- mined a decrease pH values at T2, T3, and T4 in both groups ministration is beneficial during laparoscopy of obese compared with the T1 pH value. In our study, there was no patients. difference between the two groups in terms of HCO values. Nielsen et al. [39] evaluated the effects of the RM on cen- We did not identify any difference between the groups in tral hemodynamics in situations with hypovolemia, terms of PaCO values during surgery. However, the PaCO normovolemia, and hypervolemia. They found that during 2 2 value in the recruitment group examined in blood gases at T5 hypovolemia, left ventricular end-diastolic volume and cardi- was low compared with the control group PaCO value (with- ac output significantly decreased, while hypervolemia in normal limits). With pneumoperitoneum, PaCO values prevented these effects. In our study, we administered 2 OBES SURG 15. Pelosi P, Gregoretti C. Perioperative management of obese patients. balanced IV fluid replacement to our patients to avoid hypo- Best Pract Res Clin Anaesthesiol. 2010;24(2):211–25. volemia. We did not encounter hypotension related to ventila- 16. Huschak G, Busch T, Kaisers UX. Obesity in anesthesia and inten- tor strategy in any of our patients in either group. sive care. Best Pract Res Clin Endocrinol Metab. 2013;27(2):247– Based on the findings obtained in our study, we believe 17. Fernandez-Bustamante A, Hashimoto S, Serpa Neto A, et al. adding the RM to PEEP administration for morbidly obese Perioperative lung protective ventilation in obese patients. BMC patients undergoing LSG surgery is a more effective method Anesthesiol. 2015;15:56. to improve respiratory mechanics and arterial blood gas values 18. Wetterslev J, Hansen EG, Roikjaer O, et al. Optimizing that can be used safely. peroperative compliance with PEEP during upper abdominal sur- gery: effects on perioperative oxygenation and complications in patients without preoperative cardiopulmonary dysfunction. Eur J Compliance with Ethical Standards Anaesthesiol. 2001;18(6):358–65. 19. Pelosi P, Ravagnan I, Giurati G, et al. Positive end-expiratory pres- All procedures performed in studies involving human participants were in sure improves respiratory function in obese but not in normal sub- accordance with the ethical standards of the institutional and/or national jects during anesthesia and paralysis. Anesthesiology. 1999;91(5): research committee and with the 1964 Helsinki declaration and its later 1221–31. amendments or comparable ethical standards. 20. Tusman G, Bohm SH, Vazquez de Anda GF, do Campo JL, Lachmann B. Alveolar recruitment strategy improves arterial oxy- Conflict of Interest The authors declare no conflicts of interest. genation during general anaesthesia. Br J Anaesth 1999;82(1):8– 21. Chalhoub V, Yazigi A, Sleilaty G, et al. Effect of vital capacity manoeuvres on arterial oxygenation in morbidly obese patients un- References dergoing open bariatric surgery. Eur J Anaesthesiol. 2007;24(3): 283–8. 1. WHO. Obesity Report, Updated: http://www.who.int/mediacentre/ 22. Almarakbi WA, Fawzi HM, Alhashemi JA. Effects of four intraop- factsheets/fs311/en/.2013 erative ventilatory strategies on respiratory compliance and gas ex- 2. Colquitt JL, Picot J, Loveman E, et al. Surgery for obesity. change during laparoscopic gastric banding in obese patients. Br J Cochrane Database Syst Rev. 2009;2:CD003641. Anaesth. 2009;102(6):862–8. 3. Shi X, Karmali S, Sharma AM, et al. A review of laparoscopic 23. Reinius H, Jonsson L, Gustafsson S, et al. Prevention of atelectasis sleeve gastrectomy for morbid obesity. Obes Surg. 2010;20(8): in morbidly obese patients during general anesthesia and paralysis: 1171–7. a computerized tomography study. Anesthesiology. 2009;111(5): 4. Joris JL, Hinque VL, Laurent PE, et al. Pulmonary function and 979–87. pain after gastroplasty performed via laparotomy or laparoscopy in 24. Wei K, Min S, Cao J, et al. Repeated alveolar recruitment maneu- morbidly obese patients. Br J Anaesth. 1998;80(3):283–8. vers with and without positive end-expiratory pressure during bar- 5. Shiga T, Wajima Z, Inoue T, et al. Predicting difficult intubation in iatric surgery: a randomized trial. Minerva Anestesiol. 2018;84(4): apparently normal patients: a meta-analysis of bedside screening 463–72. test performance. Anesthesiology. 2005;103(2):429–37. 25. Aldenkortt M, Lysakowski C, Elia N, et al. Ventilation strategies in 6. Strandberg A, Tokics L, Brismar B, et al. Constitutional factors obese patients undergoing surgery: a quantitative systematic review promoting development of atelectasis during anaesthesia. Acta and meta-analysis. Br J Anaesth. 2012;109(4):493–502. Anaesthesiol Scand. 1987;31(1):21–4. 26. Rothen HU, Sporre B, Engberg G, et al. Re-expansion of atelectasis 7. Salihoglu Z, Demiroluk S, Dikmen Y. Respiratory mechanics in during general anaesthesia: a computed tomography study. Br J morbid obese patients with chronic obstructive pulmonary disease Anaesth. 1993;71(6):788–95. and hypertension during pneumoperitoneum. Eur J Anaesthesiol. 27. Rothen HU, Neumann P, Berglund JE, et al. Dynamics of re- 2003;20(8):658–61. expansion of atelectasis during general anaesthesia. Br J Anaesth. 8. Perilli V, Sollazzi L, Bozza P, et al. The effects of the reverse 1999;82(4):551–6. trendelenburg position on respiratory mechanics and blood gases 28. Henzler D, Pelosi P, Dembinski R, et al. Respiratory compliance but in morbidly obese patients during bariatric surgery. Anesth Analg. not gas exchange correlates with changes in lung aeration after a 2000;91(6):1520–5. recruitment maneuver: an experimental study in pigs with saline 9. Chambers WA. The Association of Anaesthetists of Great Britain lavage lung injury. Crit Care. 2005;9(5):R471–82. and Ireland. PERI-OPERATIVE MANAGEMENT OF THE MORBIDLY OBESE PATIENT. 2007; 29. Talab HF, Zabani IA, Abdelrahman HS, et al. Intraoperative venti- latory strategies for prevention of pulmonary atelectasis in obese 10. Azab T, El-Masry A, Salah M. Effect of intraoperative use of pos- patients undergoing laparoscopic bariatric surgery. Anesth Analg. itive end expiratory pressure on lung atelectasis during laparoscopic 2009;109(5):1511–6. cholecystectomy, Egypt J Anaesth. 2005;21:219–25. 30. Golparvar M, Mofrad SZ, Mahmoodieh M, et al. Comparative 11. Eichenberger A, Proietti S, Wicky S, et al. Morbid obesity and evaluation of the effects of three different recruitment maneuvers postoperative pulmonary atelectasis: an underestimated problem. during laparoscopic bariatric surgeries of morbid obese patients on Anesth Anal. 2002;95(6):1788–92. table of contents cardiopulmonary indices. Adv Biomed Res. 2018;7:89. 12. Lebuffe G, Andrieu G, Wierre F, et al. Anesthesia in the obese. J Visc Surg. 2010;147(5 Suppl):e11–9. 31. Topuz U, Salihoglu Z, Gokay BV, et al. The effects of different 13. Murphy C, Wong DT. Airway management and oxygenation in oxygen concentrations on recruitment maneuver during general an- obese patients. Can J Anaesth. 2013;60(9):929–45. esthesia for laparoscopic surgery. Surg Laparosc Endosc Percutan Tech. 2014;24(5):410–3. 14. Whalen FX, Gajic O, Thompson GB, et al. The effects of the alve- olar recruitment maneuver and positive end-expiratory pressure on 32. Hemmes SN, Gama de Abreu M, Pelosi P, et al. High versus low arterial oxygenation during laparoscopic bariatric surgery. Anesth positive end-expiratory pressure during general anaesthesia for Analg. 2006;102(1):298–305. open abdominal surgery (PROVHILO trial): a multicentre OBES SURG randomised controlled trial. Lancet (London, England). 37. Cakmakkaya OS, Kaya G, Altintas F, et al. Restoration of pulmo- 2014;384(9942):495–503. nary compliance after laparoscopic surgery using a simple alveolar 33. Thompson CS. Acid base disorders and electrolyte imbalance. recruitment maneuver. J Clin Anesth. 2009;21(6):422–6. Compherensive respiratory care. Pennsylvania: WB saunders 38. Bardoczky GI, Engelman E, Levarlet M, et al. Ventilatory effects of Company; 1995. p. 70–97. pneumoperitoneum monitored with continuous spirometry. 34. Iwasaka H, Miyakawa H, Yamamoto H, et al. Respiratory mechan- Anaesthesia. 1993;48(4):309–11. ics and arterial blood gases during and after laparoscopic cholecys- 39. Nielsen J, Nilsson M, Freden F, et al. Central hemodynamics during tectomy. Canad J Anaesth. 1996;43(2):129–33. lung recruitment maneuvers at hypovolemia, normovolemia and 35. Sprung J, Whalley DG, Falcone T, et al. The impact of morbid hypervolemia. A study by echocardiography and continuous pul- obesity, pneumoperitoneum, and posture on respiratory system me- monary artery flow measurements in lung-injured pigs. Intensive chanics and oxygenation during laparoscopy. Anesth Analg. Care Med. 2006;32(4):585–94. 2002;94(5):1345–50. 36. Oikkonen M, Tallgren M. Changes in respiratory compliance at Publisher’sNote Springer Nature remains neutral with regard to jurisdic- laparoscopy: measurements using side stream spirometry. Can J tional claims in published maps and institutional affiliations. Anaesth. 1995;42(6):495–7. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Obesity Surgery Pubmed Central

Effect of the “Recruitment” Maneuver on Respiratory Mechanics in Laparoscopic Sleeve Gastrectomy Surgery

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Abstract

Purpose LSG surgery is used for surgical treatment of morbid obesity. Obesity, anesthesia, and pneumoperitoneum cause reduced pulmoner functions and a tendency for atelectasis. The alveolar “recruitment” maneuver (RM) keeps airway pressure high, opening alveoli, and increasing arterial oxygenation. The aim of our study is to research the effect on respiratory mechanics and arterial blood gases of performing the RM in LSG surgery. Materials and Methods Sixty patients undergoing LSG surgery were divided into two groups (n = 30) Patients in group R had the RM performed 5 min after desufflation with 100% oxygen, 40 cmH O pressure for 40 s. Group C had standard mechanical ventilation. Assessments of respiratory mechanics and arterial blood gases were made in the 10th min after induction (T1), 10th min after insufflation (T2), 5th min after desufflation (T3), and 15th min after desufflation (T4). Arterial blood gases were assessed in the 30th min (T5) in the postoperative recovery unit. Results In group R, values at T5, PaO were significantly high, while PaCO were significantly low compared with group C. 2 2 Compliance in both groups reduced with pneumoperitoneum. At T4, the compliance in the recruitment group was higher. In both groups, there was an increase in PIP with pneumoperitoneum and after desufflation this was identified to reduce to levels before pneumoperitoneum. Conclusion Adding the RM to PEEP administration for morbidly obese patients undergoing LSG surgery is considered to be effective in improving respiratory mechanics and arterial blood gas values and can be used safely. . . Keywords Laparoscopic sleeve gastrectomy Recruitment maneuver PEEP Purpose Obesity is defined as abnormal and excessive fat accumulation * Ismail Sümer isumer@bezmialem.edu.tr at levels to disrupt health [1]. Lifestyle changes like diet and exercise and medical treatment, in addition to surgical inter- ventions, are frequently used for treatment of obesity [2]. Department of Anesthesiology and Reanimation, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkey Laparoscopic sleeve gastrectomy (LSG) is a new approach for surgical treatment of morbid obesity [3]. With the increase Health Cares Vocational School, İstanbul Esenyurt University, Istanbul, Turkey in surgical interventions for obesity treatment, it is necessary to take more care for anesthesia management of these patients İstanbul Acıbadem Taksim Hospital, Istanbul, Turkey [4]. Obese patients have increased possibility of difficult intu- Department of Anesthesiology and Reanimation, Faculty of bation, in addition to displaying more unwanted effects on the Medicine, İstanbul Medipol University, Istanbul, Turkey respiratory system, compared with normal patients [5, 6]. Department of Anesthesiology and Reanimation, Faculty of Obesity is an important respiratory risk factor as it causes Medicine, Marmara University, Istanbul, Turkey 6 reduced functional residual capacity, compliance and oxygen- Department of General Surgery, Faculty of Medicine, Bezmialem ation in terms of respiratory functions before and after both Vakif University, Istanbul, Turkey 7 surgery and anesthesia, in addition to causing a tendency for Department of Anesthesiology and Reanimation, Cerrahpasa Faculty atelectasis [7, 8]. Reduced functional residual capacity causes of Medicine, İstanbul University Cerrahpasa, Istanbul, Turkey OBES SURG airway closure in situations with delayed endotracheal intuba- Healthcare, Finland), which one uses Fourier transform anal- tion and obese patients in the supine position become rapidly ysis of electroencephalographic data. Neuromuscular block- desaturated. Additionally, dyspnea, exercise intolerance, and ade was monitored from the adductor pollicis muscle inner- obstructive sleep apnea should be carefully questioned [9]. vated by the ulnar nerve with E-NMT-00 (GE Healthcare, Intraperitoneal administration of carbon dioxide (CO )gas Finland) device. Hemodynamic parameters of patients (sys- for laparoscopic surgeries frequently increases intraabdominal tolic, diastolic and mean arterial pressure, heart rate), BIS, pressure, pushing the diaphragm upwards and causing com- SpO , and TOF values were recorded perioperatively with pression of the lungs. The lungs which are already susceptible 5 min interval. to atelectasis due to general anesthesia experience increased Corrected weight calculations were performed for all severity of this effect during laparoscopy [10]. The ameliora- patients; medications and ventilatory settings were adjust- tion of atelectasis developing during general anesthesia for ed according to this calculation. For anesthesia induction, −1 −1 obese patients is slower after the operation compared with propofol 2 mg kg and rocuronium 0.6 mg kg were −1 −1 nonobese patients. Atelectasis is fully resorbed 24 h after the administered and infusions of propofol 10 mg kg hr −1 −1 end of the surgical procedure for nonobese patients, while and remifentanil 0.25 μgkg min were started. All pa- atelectasis was shown to continue in obese patients at this tients had orotracheal intubation and mechanical ventila- −1 point [11]. One of the most important aims of anesthesia man- tion with tidal volume of 6 mL kg , PEEP of 8 cmH O, −1 agement during operations on obese patients is to keep the inspired oxygen (FiO ) 40%, fresh gas flow of 4 L min airway and alveoli open during respiration [12]. The tech- and the ventilatory frequency was adjusted to keep end- niques of keeping airway pressure high for a duration to open tidal carbon dioxide (EtCO ) level between 30 and atelectatic areas with the “recruitment maneuver” (RM) and 35 mmHg. For anesthesia maintenance, propofol infusion positive expiration end pressure (PEEP) may reduce atelecta- wasadjustedtokeepBIS values between 40 and60and sis and increase oxygenation [13]. remifentanil infusion was adjusted to keep hemodynamic The primary aim of this study is to investigate the effect of parameters ± 20 of initial values. Rocuronium was added to RM on postoperative arterial oxygenation after LSG in obese keep train-of-four (TOF) response zero. patients. Our secondary aim was to investigate the effects of During the operation, all patients received 5– −1 −1 RV on perioperative respiratory mechanics. 8mLkg hr balanced electrolyte solution (isolyte-S) infu- sion. After Allen test was performed, radial artery was cannu- lated, and arterial pressure was monitorized. Arterial blood Materials and Methods gases (pH, pO , pCO , HCO , lactate) were analyzed with 2 2 3 RAPIDLab 1200 Systems (Siemens Healthcare GmbH, This study received ethics committee permission from Federal Republic of Germany). From the start of mechanical Bezmialem Vakıf University Faculty of Medicine dated ventilation, respiratory mechanics of compliance, peak inspi- 21.05.2014 numbered 71306642/050-01-04/127. The study ration pressure (PIP), plateau airway pressure (Pplateau), and included patients aged 18–65 years, American Society of airway resistance (Raw) were monitored with a spirometry Anesthesiologists (ASA) III, Body Mass Index (BMI) 40–55 device (E-COVX–Spirometry–00, GE Healthcare, Finland). undergoing elective LSG surgery after informing them about Patients who met the inclusion criteria were divided into the effects of RM performed after desufflation. Written in- two groups; one who received RM (group R, n =30) and the formed consent was obtained from all individual participants control group (group C, n = 30) without RM in a 1:1 random- included in the study. ized closed envelope manner (reviewer no. 1). Recruitment Patients with emergency operation planned, with situations maneuver applied under 100% oxygen, with 40 cmH Oair- representing contraindications to performing the RM (e.g., way pressure for 40 s duration. Patients in group R received bullous lung disease, hemodynamic instability), with respira- RM one time, 5 min after desufflation of the pneumoperito- tory and heart diseases, and using medications that affect re- neum, after RM FiO was adjusted to 40% again. If hemody- spiratory functions like salbutamol, budesonide, and namic instability and hypoxia developed, the RM was formoterol were excluded from the study. stopped. In both groups, arterial blood gas samples were ob- After routine preoperative preparation, patients with oral tained 10 min after induction (T1), 10 min after insufflation intake limited for a sufficient duration had a cannula inserted (T2), 5 min after desufflation (T3), and 15 min after in the vein on the back of the hand in the preparation room desufflation (T4) while respiratory mechanic measurements before the procedure. Premedication was not administered. (compliance, PIP, Pplateau, Raw) were recorded simulta- Patients were monitored in the operating room with a three- neously. Patients were not disconnected from the respiratory channel electrocardiogram (ECG), peripheral oxygen satura- cycle until extubation. Additionally, 30 min after extubation tion (SpO ), noninvasive blood pressure (NIBP), to estimate (T5), blood gas assessment was performed in the recovery the depth of sedation bispectral index (BIS) (E-BIS-00, GE unit. OBES SURG −1 All patients received 2 mg kg sugammadex and were weight, anesthesia duration, and surgical duration between extubated under 40% FiO when neuromuscular monitoring the groups (Table 1). TOF ratio was ≥ 0.9. In the recovery unit, all patients received There was no statistically significant difference between −1 5 L min oxygen through a face mask. For postoperative the pH values in the control and recruitment groups at T1, analgesia, 100 mg tramadol was administered 10 min before T2, T3, T4, and T5 measurements. In both groups, the pH the end of the operation and local anesthetic infiltration values measured at T1, T2, T3, T4, and T5 were statistically (bupivacaine 0.5%) was administered to the trocar entry significantly different (p < 0.001 for both groups with the points at the end of surgery. Friedman test). In both groups, blood gas pH values at T2, T3, T4, and T5 were statistically significantly low compared with the pH at T1 (p < 0.001 for all analyses with Wilcoxon Statistical Analysis signed ranks test) (Table 2 and Fig. 1). There was no statistically significant difference between The data obtained were statistically analyzed. When analyzing the groups in terms of PaO values at T1, T2, T3, and T4 findings obtained in the study, the IBM SPSS version 20 (IBM (p =0.352, p =0.092, p =0.34, p = 0.169, respectively). SPSS, Turkey) program was used for statistical analysis. A However, when the T5 value is examined, the PaO value in statistical power analysis was performed for sample size esti- group R was statistically significantly high compared with the mation, based on data from published study, Whalen et al. PaO value in group C (p = 0.017, Mann-Whitney U test) [14]. In the present study, effect size was estimated as 0.77, (Table 2 and Fig. 1). alpha was defined as 0.05, and power as 0.90, the projected When both groups are compared within themselves, the sample size needed with this effect size (GPower 3.1) is ap- PaO values at T1, T2, T3, T4, and T5 were statistically sig- proximately N = 58. A total of 29 patients would be required nificantly different (p = 0.008 for group C, p <0.001 forgroup in each group for this simplest between group comparisons. R, Friedman test). The difference observed in group C was When assessing study data, fit of parameters to normal distri- due to the T3 PaO value being statistically significantly high bution was evaluated with the Shapiro-Wilk test. When compared with the T1 PaO value (p = 0.004, Wilcoxon assessing study data, descriptive statistical methods (mean, signed ranks test). In group C, the T4 PaO value was not standard deviation, frequency) were used. For comparison of statistically significantly different from the T1, T2, and T3 quantitative data with parameters showing normal distribu- PaO values (p > 0.05, Wilcoxon signed ranks test). In group tion, two groups were compared with the student t test, while R, the T4 PaO value was statistically significantly high com- comparison of two groups without normal distribution used pared with the T1, T2, and T3 values (p =0.001, p <0.001, the Mann-Whitney U test. Analysis of more than two mea- p = 0.001, respectively), Wilcoxon signed ranks test (Table 2 surements obtained in a single group for values without nor- and Fig. 1). mal distribution used the Friedman test. Significance was At T1, T2, T3, and T4 measurements, there was no statis- assessed at p < 0.05 level. After the Friedman test, two-way tically significant difference between the groups in terms of comparisons of within-group measurements used the PaCO values (p =0.141, p =0.605, p =0.075, and p =0.107, Wilcoxon signed ranks test to identify the difference. For respectively). However, when the T5 value is examined, the blood gas measurements, significance for 5 measurements with a total of 10 two-way comparisons was evaluated at the p < 0.005 level and for respiratory mechanics, significance for Table 1 Demographic data, surgical duration, and anesthesia duration 4 measurements with a total of 6 two-way comparisons was in the groups evaluated at p < 0.008 level. Group C (n = 30) Group R (n =30) P Age (years) 38.7 ± 11.2 37.8 ± 9.7 0.74 Results Sex (F/M) 26/4 26/4 Weight (kg) 120.3 ± 17 127.97 ± 17 0.087 The study included 60 patients undergoing LSG surgery for Height (cm) 163 ± 7.7 165 ± 8.3 0.33 morbid obesity from 01.06.2014 to 01.02.2015. The mean age −2 BMI (kg m ) 45.4 ± 4.1 47.2 ± 4.6 0.12 of all patients included in the study was 38.25 ± 10.37 years. Corrected weight (kg) 81.1 ± 11 85.4 ± 11.2 0.135 There were 30 patients each in group C and group R. The sex Ideal weight (kg) 55.2 ± 8 56.8 ± 9 0.49 distribution was equal in the groups of patients included in the Anesthesia duration (min) 124 ± 18.7 130 ± 19 0.232 study. Patients did not develop any hemodynamic complica- Surgery duration (min) 88.1 ± 19.2 93 ± 19 0.322 tions. No patient required intensive care. There were no statistically significant differences between BMI, body mass index. Values given as mean ± standard deviation or patient numbers. Student t test was used the mean age, weight, height, BMI, calculated corrected OBES SURG Table 2 Analysis of pH, PaO PaCO and HCO values in the groups 2, 2, 3 T1 T2 T3 T4 T5 pH Group C (n = 30) 7.42 ± 0.04 7.37 ± 0.04 7.36 ± 0.04 7.37 ± 0.04 7.40 ± 0.05 Group R (n = 30) 7.42 ± 0.03 7.36 ± 0.03 7.34 ± 0.05 7.36 ± 0.04 7.39 ± 0.03 P 0.800 0.830 0.337 0.327 0.800 PaO (mmHg) Group C (n = 30) 163.3 ± 52.5 173.9 ± 47 177.6 ± 44.2 177 ± 62.2 151.7 ± 39 Group R (n = 30) 150.1 ± 55.7 153.4 ± 48.2 166.2 ± 47.9 211.5 ± 77.1 177.4 ± 37.9 P 0.352 0.092 0.340 0.169 0.017 PaCO2 (mmHg) Group C (n = 30) 40.8 ± 5.9 44.6 ± 4.8 42.7 ± 4.9 40.4 ± 5.7 42.7 ± 4.2 c c c e Group R (n = 30) 39.1 ± 4.1 44.1 ± 3.4 45.2±6 42.4±6 39.9 ± 2.7 P 0.141 0.605 0.075 0.107 0.012 f f f HCO Group C (n = 30) 25.8 ± 2.5 25.4 ± 2.2 24.2 ± 2.5 23.4 ± 2.5 22.8 ± 2.8 Group R (n = 30) 25 ± 2.2 24.9 ± 1.9 24.6 ± 2.4 24 ± 2.3 23.8 ± 1.9 P 0.158 0.375 0.559 0.308 0.096 PaO , arterial oxygen pressure; PaCO , arterial carbon dioxide pressure; HCO , bicarbonate value. Values give as mean ± standard deviation. 2 2 3 Comparisons between groups used Mann-Whitney U test; comparisons within groups used Wilcoxon signed ranks test Comparison between groups is statistically significant Within groups, comparisons with T2, T3, T4, and T5 are statistically significant Within groups, comparisons with T1 are statistically significant Within groups, comparisons with T1, T2, and T3 are statistically significant Within groups, comparisons with T2 and T3 are statistically significant Within groups, comparisons with T1 and T2 are statistically significant PaCO value in group R was statistically significantly low The PaCO values measured at T1, T2, T3, T4, and T5 2 2 compared with the PaCO value in group C (p =0.012, were statistically significantly different within both groups Mann-Whitney U test) (Table 2 and Fig. 1). (p < 0.001 for both groups, Friedman test). In group C, this 220,0 211,5 pH PaO (mmHg) PaCO (mmHg) 2 2 46,0 200,0 45,2 44,6 7,45 177,6 44,0 173,9 7,42 180,0 177,4 42,7 177,0 44,1 42,7 7,4 7,42 42,4 7,40 163,3 42,0 7,39 7,37 160,0 7,37 7,36 166,2 40,8 151,7 7,36 150,1 7,35 7,36 40,0 39,9 153,4 40,4 140,0 39,1 7,34 38,0 7,3 120,0 T1 T2 T3 T4 T5 T1 T2 T3 T4 T5 36,0 T1 T2 T3 T4 T5 C R C R C R -1 -1 HCO (mmol.L ) Lactate (mmol.L ) SpO 1,06 1,1 99,6 99,6 27,0 100,0 0,97 98,8 99,1 26,0 1 25,4 25,8 99,0 98,2 99,4 24,6 25,0 25,0 99,0 99,1 0,95 24,0 0,86 0,86 24,9 0,9 98,0 24,0 23,8 24,2 97,8 0,82 98,0 23,0 22,8 97,0 23,4 0,77 0,8 22,0 0,82 0,79 96,0 21,0 T1 T2 T3 T4 T5 T1 T2 T3 T4 T5 0,7 T1 T2 T3 T4 T5 C R C R C R Fig. 1 Graphs of pH, PaO PaCO HCO and SpO variations in groups 2, 2, 3, 2 OBES SURG difference was due to the T2 PaCO value being statistically statistically significantly low compared with the T1 and T2 significantly high compared with the T1 PaCO value measurements (p <0.001, p < 0.001, Wilcoxon signed ranks (p < 0.001, Wilcoxon signed ranks test). In group R, the T2, test). In group R, this difference was due to the T3 Raw value T3, and T4 measurements were statistically significantly high being statistically significantly low compared with the T1 and compared with the T1 measurements (p < 0.001, p < 0.001, T2 Raw values (p =0.002, p = 0.004, respectively) and the T4 p = 0.003, respectively, Wilcoxon signed ranks test). Raw value being statistically significantly low compared with Additionally, the T5 value was statistically significantly low the T1 value (p = 0.002, Wilcoxon signed ranks test) (Table 3 compared with the T1 and T2 values (p <0.001, p =0.001, and Fig. 2). respectively, Wilcoxon signed ranks test) (Table 2 and Fig. 1). There was no statistically significant difference between There was no statistically significant difference between the PIP measurement values in the groups at T1, T2, T3, and the HCO values between the groups at T1, T2, T3, T4, and T4 measurements (Mann-Whitney U test) (Table 3 and Fig. T5 measurements (Mann-Whitney U test) (Table 2 and Fig. 2). 1). Within both groups, the PIP values measured at T1, T2, T3, Within group C, HCO values in blood gas measurements and T4 were statistically significantly different (p < 0.001 for at T1, T2, T3, T4, and T5 were statistically significantly dif- both groups, Friedman test). This difference in both groups ferent (p < 0.001, Friedman test). This difference in group C was due to the T2 PIP value being statistically significantly was due to the T3 HCO value being statistically significantly high compared with the T1, T3, and T4 PIP measurements lower than the T1 and T2 values, (p =0.001, p <0.001, re- (p < 0.001 for all measures in both groups, Wilcoxon signed spectively); the T4 HCO value being statistically significant- ranks test) (Table 3 and Fig. 2). ly low compared with the T1 and T2 values (p < 0.001, The Pplateau values at T1, T2, T3, and T4 measurements in p < 0.001, respectively); and the T5 HCO value being statis- both groups were not statistically significantly different tically significantly low compared with the T1 and T2 values (Mann-Whitney U test) (Table 3 and Fig. 2). (p <0.001, p = 0.001, respectively, Wilcoxon signed ranks Within both groups, the T1, T2, T3, and T4 Pplateau values test) (Table 2 and Fig. 1). were statistically significantly different (p < 0.001 in both There was no statistically significant difference between groups, Friedman test). This difference was due to the T2 the lactate values between the groups at T1, T2, T3, T4, and Pplateau value being statistically significantly high compared T5 measurements (Mann-Whitney U test). with the T1, T3, and T4 Pplateau measurements in both There was no statistically significant difference between groups (p < 0.001 for all measures in both groups, Wilcoxon the compliance values in the groups at T1, T2, and T3 mea- signed ranks test) (Table 3 and Fig. 2). surements. However, when the T4 compliance value is exam- ined, the compliance in group R was statistically significantly high compared with the compliance in group C (p =0.043, Discussion Mann-Whitney U test) (Table 2 and Fig. 2). Within both groups, the compliance values measured at T1, There is no guideline with definite rules for ventilation strat- T2, T3, and T4 were statistically significantly different egies in obese patients. However, in the literature, PEEP ap- (p < 0.001, Friedman test). The compliance value measured plied after the recruitment maneuver and less than 80% FiO at T4 in group C was not statistically different from the com- administration methods recommended to maintain physiolog- pliance value measured at T1, while it was significantly higher ical oxygenation [15, 16]. Lung-protective ventilation strategy −1 than the T2 value (p < 0.001, Wilcoxon signed ranks test). In (aproximately 8 ml kg tidal volume and administered using group R, the T4 compliance value was found to be statistically estimated true body weight), PEEP administration, and alve- significantly high compared with the T1, T2, and T3 measure- olar recruitment maneuvers prevent atelectasis and positively ments (p < 0.001 for all, Wilcoxon signed ranks test) (Table 2 affect intraoperative gas exchange which prevents the devel- and Fig. 2). opment of hypoxemia [12, 17]. High PEEP administration There was no statistically significant difference in terms of prevents the decrease in lung volume at the end of expirium the Raw values in the control group and recruitment group at formed by increased intraabdominal pressure and in this way T1, T2, T3, and T4 measurements (Mann-Whitney U test) is reported to have positive effects on respiratory mechanics, (Table 3 and Fig. 2). gas exchange, and PaO values in morbidly obese patients Within both groups, the Raw values measured at T1, T2, [18, 19]. A variety of studies have reported that administration T3, and T4 were statistically significantly different (p <0.001 of PEEP with the RM ensures better oxygenation and compli- for both groups, Friedman test). This difference in group C ance compared with patients with only PEEP applied [20–24]. was due to the T3 Raw value being statistically significantly With the aim of investigating the effects of PEEP and recruit- low compared with the T1 and T2 Raw values (p < 0.001, ment, there are studies performed by CT or MR imaging for p < 0.001); additionally, in group C the T4 Raw value was each patient and evaluated according to the results of these OBES SURG -1 -1 -1 Compliance (ml.cmH O ) RAW (cmH O.lt .sn ) 2 2 50 17 16,6 16,1 40,2 45,6 16,2 15,2 37,4 39 14,4 28,2 34,6 13,1 27,3 13,1 20 12 T1 T2 T3 T4 T1 T2 T3 T4 C R C R PIP (cmH O) Pplateau (cmH O) 2 2 27,6 32 29 30,3 30 27 28 25 30,1 26,1 26,4 24,7 23,4 26 23 21,5 22,5 21,8 26,2 24 21 24,5 20,4 21,3 22 19 T1 T2 T3 T4 T1 T2 T3 T4 C R C R Fig. 2 Graphs of compliance, Raw, PIP, and Pplateau variations in groups imaging methods [25–27]. Two studies by Rothen et al. [26, They reported that 40 cmH O with 5 multiple deep breathing 27] administered at least 40 cmH O pressure for 7–8 s dura- was less effective than only PEEP administration or both used tion and observed that all atelectatic lung tissues opened, there together. In our study, during the operation, PEEP adminis- was a marked reduction in the amount of shunt and oxygena- trated with 8 cmH O at the beginning before insufflation tion significantly improved. Henzler et al. [28]inan animal lasted until the end of the operation, while the RM was per- study performed the recruitment maneuver with 45 cmH O formed 5 min after desufflation with 40 cmH O pressure for 2 2 pressure for 40 s and found the RM provided an increase in 40 s duration. We used 100% oxygen only during the RM and ventilation of weakly ventilated lung volumes. In our study, as part of this maneuver for only 40 s. This is the limitation of we attempted to determine the efficacy of PEEP and RM using our study. Although we used this FiO value, there was no respiratory mechanics values and arterial blood gas measure- difference between the groups in the T4 measurements per- ments due to the cost increase caused by these imaging formed at the 15th min after desufluation. T5 was the 30th min methods and the technical difficulties of performing CT and measurement after extubation and the difference between the MR imaging for obese patients. We used PEEP and the RM two groups appeared in this measurement. This difference was together. Talab et al. [29] stated there was better oxygenation, more relevant with the pressure and duration we used. In fact, less atelectasis, and less postoperative respiratory complica- in one study, recruitment maneuver with low oxygen concen- tions with no barotrauma encountered in the group with tration has been shown to be more effective for oxygenation. 10 cmH O PEEP and 40 cmH O recruitment procedure for [31] We found that the PaO value in the recruitment group 2 2 2 7–8 s. Golparvar et al. [30] performed in their study in 3 was significantly high compared with the control group at T5. groups; multiple deep breathing maneuvers, PEEP, and both. Hemmes et al. [32] administered high PEEP (12 cmH O) to 2 OBES SURG Table 3 Comparison of compliance, raw, PIP, and Pplateau values in groups T1 T2 T3 T4 Compliance Group C (n = 30) 34.6 ± 8.1 27.3 ± 5.6 39 ± 9 37.4 ± 8.2 Group R (n = 30) 35.8 ± 11.3 28.2 ± 6.3 40.2 ± 11.1 45.6±15 P 0.988 0.888 0.941 0.043 −1 −1 d d Raw (cmH Olt sn ) Group C (n = 30) 16.6 ± 5.7 15.2 ± 3.6 13.1 ± 3.2 13.1 ± 3.1 d e Group R (n = 30) 16.2 ± 5.6 16.1 ± 4.4 14 ± 3.6 14.4 ± 4.8 P 0.629 0.474 0.368 0.38 PIP (cmH O) Group C (n = 30) 26.2 ± 4.5 30.3 ± 3.8 24.5 ± 3.3 25 ± 3.3 Group R (n = 30) 26.4 ± 4.2 30.1 ± 3.4 24.7 ± 4.7 24 ± 4.1 P 0.795 0.818 0.97 0.176 Pplateau (cmH O) Group C (n = 30) 22.5 ± 4.7 26.1 ± 5.6 21.3 ± 3 21.8 ± 3.2 Group R (n = 30) 23.4 ± 3.8 27.6 ± 3.5 21.5 ± 4.6 20.4 ± 4 P 0.543 0.338 0.87 0.132 Raw, air way resistance; PIP, peak inspiratory pressure; Pplateau, plateau pressure. Values given as mean ± standard deviation. Comparisons between groups used Mann-Whitney U test; comparisons within groups used Wilcoxon sign test Comparison between groups is statistically significant Within groups, comparisons with T2 are statistically significant Within groups, comparisons with T1, T2, and T3 are statistically significant Within groups, comparisons with T1 and T2 are statistically significant Within groups, comparisons with T1 statistically significant Within groups, comparisons with T1, T3, and T4 are statistically significant obese patients undergoing open abdominal surgery and stated increase, while this value decreases after pneumoperitoneum it was not protective in terms of postoperative pulmonary and we identified that this was significant in the recruitment complications. They stated that for intraoperative protective group. ventilation strategy, it is necessary to ensure low TV and low Sprung et al. [35] reported a 30% reduction in compliance PEEP (2 cmH O) without recruitment. Our study group and 68% increase in Raw in supine position for morbidly underwent laparoscopic surgery and there are studies showing obese patients compared with normal weight patients. In lap- that due to the negative effects on lung dynamics, our patients aroscopic surgery, PIP, Raw, and Pplateau increase, compli- were more susceptible to atelectasis development [7, 8, 10]. ance decreases [35–38]. After desufflation, PIP and Pplateau Findings during open surgery may be different from laparo- decrease andcomplianceincreases; however,it was shown to scopic surgery. As a result, we applied relatively high PEEP be 14% reduced compared with the value before insufflation along with the RM in our study. [38]. It is proposed that the RM performed after desufflation Arterial blood gas analysis are one of the best methods to in laparoscopic surgery is effective to completely regain lung assess pulmonary function. The first parameter examined to compliance [35]. According to the data obtained in our study, assess the acid-base balance is pH [33]. Iwasaka et al. [34] we thinkthe RM performedwithPEEPhas greaterpositive investigated that blood gas analysis during laparoscopic sur- effects on compliance. When Rawis investigated,contrary to gery with increased intraabdominal pressure and CO insuf- previous studies [36], we found Raw reduced during surgery. flation decreases in arterial pH and increases in PaCO values PIP values in both groups increased with insufflation, and we due to CO retention. When we assessed pH, HCO ,and identified they regressed to values before pneumoperitone- 2 3 PaCO data in our study, we did not identify a difference um with desufflation. Based on the findings from Raw and between the two groups for pH values; however, we deter- PIP measurements, we concluded that 8 cmH O PEEP ad- mined a decrease pH values at T2, T3, and T4 in both groups ministration is beneficial during laparoscopy of obese compared with the T1 pH value. In our study, there was no patients. difference between the two groups in terms of HCO values. Nielsen et al. [39] evaluated the effects of the RM on cen- We did not identify any difference between the groups in tral hemodynamics in situations with hypovolemia, terms of PaCO values during surgery. However, the PaCO normovolemia, and hypervolemia. They found that during 2 2 value in the recruitment group examined in blood gases at T5 hypovolemia, left ventricular end-diastolic volume and cardi- was low compared with the control group PaCO value (with- ac output significantly decreased, while hypervolemia in normal limits). With pneumoperitoneum, PaCO values prevented these effects. In our study, we administered 2 OBES SURG 15. Pelosi P, Gregoretti C. Perioperative management of obese patients. balanced IV fluid replacement to our patients to avoid hypo- Best Pract Res Clin Anaesthesiol. 2010;24(2):211–25. volemia. We did not encounter hypotension related to ventila- 16. Huschak G, Busch T, Kaisers UX. Obesity in anesthesia and inten- tor strategy in any of our patients in either group. sive care. Best Pract Res Clin Endocrinol Metab. 2013;27(2):247– Based on the findings obtained in our study, we believe 17. Fernandez-Bustamante A, Hashimoto S, Serpa Neto A, et al. adding the RM to PEEP administration for morbidly obese Perioperative lung protective ventilation in obese patients. BMC patients undergoing LSG surgery is a more effective method Anesthesiol. 2015;15:56. to improve respiratory mechanics and arterial blood gas values 18. Wetterslev J, Hansen EG, Roikjaer O, et al. Optimizing that can be used safely. peroperative compliance with PEEP during upper abdominal sur- gery: effects on perioperative oxygenation and complications in patients without preoperative cardiopulmonary dysfunction. Eur J Compliance with Ethical Standards Anaesthesiol. 2001;18(6):358–65. 19. Pelosi P, Ravagnan I, Giurati G, et al. Positive end-expiratory pres- All procedures performed in studies involving human participants were in sure improves respiratory function in obese but not in normal sub- accordance with the ethical standards of the institutional and/or national jects during anesthesia and paralysis. Anesthesiology. 1999;91(5): research committee and with the 1964 Helsinki declaration and its later 1221–31. amendments or comparable ethical standards. 20. Tusman G, Bohm SH, Vazquez de Anda GF, do Campo JL, Lachmann B. Alveolar recruitment strategy improves arterial oxy- Conflict of Interest The authors declare no conflicts of interest. genation during general anaesthesia. Br J Anaesth 1999;82(1):8– 21. Chalhoub V, Yazigi A, Sleilaty G, et al. Effect of vital capacity manoeuvres on arterial oxygenation in morbidly obese patients un- References dergoing open bariatric surgery. Eur J Anaesthesiol. 2007;24(3): 283–8. 1. WHO. Obesity Report, Updated: http://www.who.int/mediacentre/ 22. Almarakbi WA, Fawzi HM, Alhashemi JA. Effects of four intraop- factsheets/fs311/en/.2013 erative ventilatory strategies on respiratory compliance and gas ex- 2. Colquitt JL, Picot J, Loveman E, et al. Surgery for obesity. change during laparoscopic gastric banding in obese patients. Br J Cochrane Database Syst Rev. 2009;2:CD003641. Anaesth. 2009;102(6):862–8. 3. Shi X, Karmali S, Sharma AM, et al. A review of laparoscopic 23. Reinius H, Jonsson L, Gustafsson S, et al. Prevention of atelectasis sleeve gastrectomy for morbid obesity. Obes Surg. 2010;20(8): in morbidly obese patients during general anesthesia and paralysis: 1171–7. a computerized tomography study. Anesthesiology. 2009;111(5): 4. Joris JL, Hinque VL, Laurent PE, et al. Pulmonary function and 979–87. pain after gastroplasty performed via laparotomy or laparoscopy in 24. Wei K, Min S, Cao J, et al. Repeated alveolar recruitment maneu- morbidly obese patients. Br J Anaesth. 1998;80(3):283–8. vers with and without positive end-expiratory pressure during bar- 5. Shiga T, Wajima Z, Inoue T, et al. Predicting difficult intubation in iatric surgery: a randomized trial. Minerva Anestesiol. 2018;84(4): apparently normal patients: a meta-analysis of bedside screening 463–72. test performance. Anesthesiology. 2005;103(2):429–37. 25. Aldenkortt M, Lysakowski C, Elia N, et al. Ventilation strategies in 6. Strandberg A, Tokics L, Brismar B, et al. Constitutional factors obese patients undergoing surgery: a quantitative systematic review promoting development of atelectasis during anaesthesia. Acta and meta-analysis. Br J Anaesth. 2012;109(4):493–502. Anaesthesiol Scand. 1987;31(1):21–4. 26. Rothen HU, Sporre B, Engberg G, et al. Re-expansion of atelectasis 7. Salihoglu Z, Demiroluk S, Dikmen Y. Respiratory mechanics in during general anaesthesia: a computed tomography study. Br J morbid obese patients with chronic obstructive pulmonary disease Anaesth. 1993;71(6):788–95. and hypertension during pneumoperitoneum. Eur J Anaesthesiol. 27. Rothen HU, Neumann P, Berglund JE, et al. Dynamics of re- 2003;20(8):658–61. expansion of atelectasis during general anaesthesia. Br J Anaesth. 8. Perilli V, Sollazzi L, Bozza P, et al. The effects of the reverse 1999;82(4):551–6. trendelenburg position on respiratory mechanics and blood gases 28. Henzler D, Pelosi P, Dembinski R, et al. Respiratory compliance but in morbidly obese patients during bariatric surgery. Anesth Analg. not gas exchange correlates with changes in lung aeration after a 2000;91(6):1520–5. recruitment maneuver: an experimental study in pigs with saline 9. Chambers WA. The Association of Anaesthetists of Great Britain lavage lung injury. Crit Care. 2005;9(5):R471–82. and Ireland. PERI-OPERATIVE MANAGEMENT OF THE MORBIDLY OBESE PATIENT. 2007; 29. Talab HF, Zabani IA, Abdelrahman HS, et al. Intraoperative venti- latory strategies for prevention of pulmonary atelectasis in obese 10. Azab T, El-Masry A, Salah M. Effect of intraoperative use of pos- patients undergoing laparoscopic bariatric surgery. Anesth Analg. itive end expiratory pressure on lung atelectasis during laparoscopic 2009;109(5):1511–6. cholecystectomy, Egypt J Anaesth. 2005;21:219–25. 30. Golparvar M, Mofrad SZ, Mahmoodieh M, et al. Comparative 11. Eichenberger A, Proietti S, Wicky S, et al. Morbid obesity and evaluation of the effects of three different recruitment maneuvers postoperative pulmonary atelectasis: an underestimated problem. during laparoscopic bariatric surgeries of morbid obese patients on Anesth Anal. 2002;95(6):1788–92. table of contents cardiopulmonary indices. Adv Biomed Res. 2018;7:89. 12. Lebuffe G, Andrieu G, Wierre F, et al. Anesthesia in the obese. J Visc Surg. 2010;147(5 Suppl):e11–9. 31. Topuz U, Salihoglu Z, Gokay BV, et al. The effects of different 13. Murphy C, Wong DT. Airway management and oxygenation in oxygen concentrations on recruitment maneuver during general an- obese patients. Can J Anaesth. 2013;60(9):929–45. esthesia for laparoscopic surgery. Surg Laparosc Endosc Percutan Tech. 2014;24(5):410–3. 14. Whalen FX, Gajic O, Thompson GB, et al. The effects of the alve- olar recruitment maneuver and positive end-expiratory pressure on 32. Hemmes SN, Gama de Abreu M, Pelosi P, et al. High versus low arterial oxygenation during laparoscopic bariatric surgery. Anesth positive end-expiratory pressure during general anaesthesia for Analg. 2006;102(1):298–305. open abdominal surgery (PROVHILO trial): a multicentre OBES SURG randomised controlled trial. Lancet (London, England). 37. Cakmakkaya OS, Kaya G, Altintas F, et al. Restoration of pulmo- 2014;384(9942):495–503. nary compliance after laparoscopic surgery using a simple alveolar 33. Thompson CS. Acid base disorders and electrolyte imbalance. recruitment maneuver. J Clin Anesth. 2009;21(6):422–6. Compherensive respiratory care. Pennsylvania: WB saunders 38. Bardoczky GI, Engelman E, Levarlet M, et al. Ventilatory effects of Company; 1995. p. 70–97. pneumoperitoneum monitored with continuous spirometry. 34. Iwasaka H, Miyakawa H, Yamamoto H, et al. Respiratory mechan- Anaesthesia. 1993;48(4):309–11. ics and arterial blood gases during and after laparoscopic cholecys- 39. Nielsen J, Nilsson M, Freden F, et al. Central hemodynamics during tectomy. Canad J Anaesth. 1996;43(2):129–33. lung recruitment maneuvers at hypovolemia, normovolemia and 35. Sprung J, Whalley DG, Falcone T, et al. The impact of morbid hypervolemia. A study by echocardiography and continuous pul- obesity, pneumoperitoneum, and posture on respiratory system me- monary artery flow measurements in lung-injured pigs. Intensive chanics and oxygenation during laparoscopy. Anesth Analg. Care Med. 2006;32(4):585–94. 2002;94(5):1345–50. 36. Oikkonen M, Tallgren M. Changes in respiratory compliance at Publisher’sNote Springer Nature remains neutral with regard to jurisdic- laparoscopy: measurements using side stream spirometry. Can J tional claims in published maps and institutional affiliations. Anaesth. 1995;42(6):495–7.

Journal

Obesity SurgeryPubmed Central

Published: Mar 23, 2020

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