Canadian Journal of Anesthesia/Journal canadien d anesthésie

Lazzareschi, Daniel V.; Luo, Yanting; Fong, Nicholas; Boscardin, John; Legrand, Matthieu; Chen, Catherine L.

doi: 10.1007/s12630-023-02639-4pmid: 38102451

PurposeWe sought to evaluate the synergistic risk of postoperative thrombosis in patients with a history of COVID-19 who undergo major surgery. Major surgery and SARS-CoV-2 infection are independently associated with an increased risk of thrombosis, but the magnitude of additional risk beyond surgery conferred by a COVID-19 history on the development of perioperative thrombotic events has not been clearly elucidated in the literature.MethodsWe conducted a retrospective cohort study among commercially insured adults in the USA from March 2020 to June 2021 using the Optum Labs Data Warehouse (OLDW), a longitudinal, real-world data asset containing deidentified administrative claims and electronic health records. We compared patients with prior COVID-19 who underwent surgery with control individuals who underwent surgery without a COVID-19 history and with control individuals who did not undergo surgery with and without a COVID-19 history. We assessed the interaction of surgery and previous COVID-19 on perioperative thrombotic events (venous thromboembolism and major adverse cardiovascular events) within 90 days using multivariable logistic regression and interaction analysis.ResultsTwo million and two-hundred thousand eligible patients were identified from the OLDW. Patients in the surgical cohorts were older and more medically complex than nonsurgical population controls. After adjusting for confounders, only surgical exposure—not COVID-19 history—remained associated with perioperative thrombotic events (adjusted odds ratio [aOR], 4.07; 95% confidence interval [CI], 3.81 to 4.36). The multiplicative interaction term (aOR, 1.25; 95% CI, 0.96 to 1.61) and the synergy index (0.76; 95% CI, 0.56 to 1.04) suggest minimal effect modification of prior COVID-19 on surgery with regards to overall thrombotic risk.ConclusionsWe found no evidence of synergistic thrombotic risk from previous COVID-19 in patients who underwent selected major surgery relative to the baseline thrombotic risk from surgery alone.

Chaki, Tomohiro; Koizumi, Masatsugu; Tachibana, Shunsuke; Matsumoto, Tomomi; Kumagai, Tomoe; Hashimoto, Yuki; Yamakage, Michiaki

doi: 10.1007/s12630-023-02648-3pmid: 38017196

PurposeThe effect of head rotation on supraglottic airway (SGA) oropharyngeal leak pressure (OPLP) has not been well elucidated. The aim of this study was to help clarify which SGA device provides higher OPLP at head-rotated position.MethodsPatients who underwent elective surgery under general anesthesia were enrolled and randomly divided into laryngeal mask airway (LMA®) ProSeal™ and i-gel® groups. The allocated SGA device was inserted under anesthesia. The primary outcome was OPLP, and secondary outcomes were ventilation score, expiratory tidal volume, and maximum pressure under volume-controlled ventilation (VCV) with an inspiratory tidal volume of 10 mL·kg−1 ideal body weight and fibreoptic view of the vocal cords at 0°, 30°, and 60° head rotation.ResultsData from 78 and 76 patients were analyzed in the LMA ProSeal and i-gel groups, respectively. The mean (standard deviation) OPLP of the LMA ProSeal was significantly higher than that of the i-gel at the 60° head-rotated position (LMA ProSeal, 20.4 [6.5] vs i-gel, 16.9 [7.8] cm H2O; difference in means, 3.6; adjusted 95% confidence interval, 0.5 to 6.6; adjusted P = 0.02, adjusted for six comparisons). The maximum pressure under VCV at 60° head rotation was significantly higher in the LMA ProSeal group than in the i-gel group. The expiratory tidal volume of the LMA ProSeal did not significantly change with head rotation and was significantly higher than that of the i-gel at 60° head rotation. Ventilation score, fibreoptic view of the vocal cords, and complications were not significantly different between the ProSeal and i-gel groups.ConclusionsThe LMA ProSeal provides higher OPLP than the i-gel at a 60° head-rotated position under general anesthesia.Trial registrationJapan Registry of Clinical Trials (https://jrct.niph.go.jp) (JRCT1012210043); registered 18 October 2021.

King, Michael R.; De Souza, Elizabeth; Anderson, Thomas A.

doi: 10.1007/s12630-023-02612-1pmid: 37919633

PurposeIn children, the relationship between the dose of intraoperative opioid and postoperative outcomes is unclear. We examined the relationship between intraoperative opioid dose and postanesthesia care unit (PACU) pain scores and opioid and antiemetic administrations.MethodsWe performed a single-institution retrospective cohort study. Patients who were aged < 19 yr, had an American Society of Anesthesiologists Physical Status of I–III, were undergoing one of 11 procedures under general anesthesia and without regional anesthesia, and who were admitted to the PACU were included. Patients were analyzed by quartiles of total intraoperative opioid dose using multivariable regression, adjusting for confounders including procedure. An exploratory analysis of opioid-free anesthetics was also performed.ResultsThree thousand, seven hundred and thirty-three cases were included, and the mean age of included patients was 8.3 yr. After adjustment, there were no significant differences between the lowest and higher quartiles for first conscious pain score, mean pain score, PACU opioid dose, or PACU length of stay; in addition, estimated differences were small. Patients in higher quartiles were estimated to be more likely to receive antiemetics, significantly so for those in the second quartile. Patients in the lowest quartile received significantly more intraoperative nonopioid analgesics. In the exploratory analysis, no significant difference in PACU pain scores was found in cases without intraoperative opioids.ConclusionsChildren who received lower doses of intraoperative opioids did not have worse PACU pain outcomes but required fewer antiemetics and received greater numbers of nonopioid analgesics intraoperatively. These findings suggest that lower doses of intraoperative opioids may be administered to children as long as other analgesics are used.

Scott, Talia A.; Mercedes, Cynthia R.; Lin, Hung-Mo; Katz, Daniel

doi: 10.1007/s12630-023-02635-8pmid: 37919628

PurposeAlthough many patients agree to participate in research studies, many decline. The decision of whether or not to participate is especially complex in pregnant individuals as they may be concerned about both themselves and the fetus. We sought to understand patient reasoning for and demographic associations with participation in a trial surrounding the utility of epidural preservative-free morphine after successful vaginal delivery.MethodsWe conducted a survey-based study in which parturients were approached within 36 hr after delivery to complete a survey assessing reasons for why they participated or not in the original trial. The survey also included self-reported demographics. Survey responses were categorized as follows: active participation, passive participation, ambivalence, aversion, miscommunication, clinical difficulty, unwilling to receive placebo, and screening failures.ResultsThe survey response rate was 47%. Having a bachelor’s degree or higher was associated with participating in the study (odds ratio [OR], 1.97; 95% confidence interval [CI], 1.07 to 3.64; P = 0.03). Race and ethnicity were not predictive of participation. Participants who self-identified as Black were more likely to select reasons of aversion for why they did not participate in the trial (OR, 2.6; 95% CI, 1.00 to 6.75; P = 0.05). Seventy-three percent of participants who self-identified as Black and declined to participate selected aversion, compared with 31% of those who self-identified as non-Black. Additionally, 71% of participants who self-identified as Hispanic and declined to participate selected aversion, compared with 32% of those who self-identified as non-Hispanic.ConclusionsThese findings can help identify areas for improvement of participation of pregnant individuals in research studies. Demographic associations may influence participation and reasons for participation.

Nourian, Maziar M.; Alshibli, Amany; Kamau, John; Nabulindo, Susan; Amollo, Dennis A.; Connell, Jennifer; Eden, Svetlana K.; Seyoum, Rahel; Teklehaimanot, Masresha G.; Tegu, Gebrehiwot A.; Desta, Haftom B.; Newton, Mark; Sileshi, Bantayehu

doi: 10.1007/s12630-023-02607-ypmid: 37914969

PurposeLack of access to safe and affordable anesthesia and monitoring equipment may contribute to higher rates of morbidity and mortality in low- and middle-income countries (LMICs). While capnography is standard in high-income countries, use in LMICs is not well studied. We evaluated the association of capnography use with patient and procedure-related characteristics, as well as the association of capnography use and mortality in a cohort of patients from Kenya and Ethiopia.MethodsFor this retrospective observational study, we used historical cohort data from Kenya and Ethiopia from 2014 to 2020. Logistic regression was used to study the association of capnography use (primary outcome) with patient/procedure factors, and the adjusted association of intraoperative, 24-hr, and seven-day mortality (secondary outcomes) with capnography use.ResultsA total of 61,792 anesthetic cases were included in this study. Tertiary or secondary hospital type (compared with primary) was strongly associated with use of capnography (odds ratio [OR], 6.27; 95% confidence interval [CI], 5.67 to 6.93 and OR, 6.88; 95% CI, 6.40 to 7.40, respectively), as was general (vs regional) anesthesia (OR, 4.83; 95% CI, 4.41 to 5.28). Capnography use was significantly associated with lower odds of intraoperative mortality in patients who underwent general anesthesia (OR, 0.31; 95% CI, 0.17 to 0.48). Nevertheless, fully-adjusted models for 24-hr and seven-day mortality showed no evidence of association with capnography.ConclusionCapnography use in LMICs is substantially lower compared with other standard anesthesia monitors. Capnography was used at higher rates in tertiary centres and with patients undergoing general anesthesia. While this study revealed decreased odds of intraoperative mortality with capnography use, further studies need to confirm these findings.

Khan, Jasmine M.; Shore, Abigail; Lee, Kevin F. H.; Wood, Michael D.; Maslove, David M.; Hunt, Miranda; Georgescu, Ilinca; Muscedere, John; Boyd, J. Gordon

doi: 10.1007/s12630-023-02609-wpmid: 37932650

PurposeCerebral autoregulation (CA) is a mechanism that acts to maintain consistent cerebral perfusion across a range of blood pressures, and impaired CA is associated with delirium. Individualized CA-derived blood pressure targets are poorly characterized in critically ill patients and the association with intensive care unit (ICU) delirium is unknown. Our objectives were to characterize optimal mean arterial pressure (MAPopt) ranges in critically ill adults without brain injury and determine whether deviations from these targets contribute to ICU delirium.MethodsWe performed a retrospective cohort analysis of patients with shock of any etiology and/or respiratory failure requiring invasive mechanical ventilation, without a neurologic admitting diagnosis. Patients were screened daily for delirium. Cerebral oximetry and mean arterial pressure data were captured for the first 24 hr from enrolment.ResultsForty-two patients with invasive blood pressure monitoring data were analyzed. Optimal mean arterial pressure targets ranged from 55 to 100 mm Hg. Optimal mean arterial pressure values were not significantly different based on history of hypertension or delirium status, and delirium was not associated with deviations from MAPopt. Nevertheless, the majority (69%) of blood pressure targets exceeded the current 65 mm Hg Surviving Sepsis guidelines.ConclusionWe observed that MAPopt targets across patients were highly variable, but did not observe an association with the incidence of delirium. Studies designed to evaluate the impact on neurologic outcomes are needed to understand the association with individualized mean arterial pressure targets in the ICU.Study registrationClinicalTrials.gov (NCT02344043); first submitted 22 January 2015.

Sharif, Sameer; Munshi, Laveena; Burry, Lisa; Mehta, Sangeeta; Gray, Sara; Chaudhuri, Dipayan; Duffett, Mark; Siemieniuk, Reed A.; Rochwerg, Bram

doi: 10.1007/s12630-023-02608-xpmid: 37884773

PurposeWe sought to understand the beliefs and practices of Canadian intensivists regarding their use of ketamine as a sedative in critically ill patients and to gauge their interest in a randomized controlled trial (RCT) examining its use in the intensive care unit (ICU).MethodsWe designed and validated an electronic self-administered survey examining the use of ketamine as a sedative infusion for ICU patients. We surveyed 400 physician members of the Canadian Critical Care Society (CCCS) via email between February and April 2022 and sent three reminders at two-week intervals. The survey was redistributed in January 2023 to improve the response rate.ResultsWe received 87/400 (22%) completed questionnaires. Most respondents reported they rarely use ketamine as a continuous infusion for sedation or analgesia in the ICU (52/87, 58%). Physicians reported the following conditions would make them more likely to use ketamine: asthma exacerbation (73/87, 82%), tolerance to opioids (68/87, 77%), status epilepticus (44/87, 50%), and severe acute respiratory distress syndrome (33/87, 38%). Concern for side-effects that limited respondents’ use of ketamine include adverse psychotropic effects (61/87, 69%) and delirium (47/87, 53%). The majority of respondents agreed there is need for an RCT to evaluate ketamine as a sedative infusion in the ICU (62/87, 71%).ConclusionThis survey of Canadian intensivists illustrates that use of ketamine as a continuous infusion for sedation is limited, and is at least partly driven by concerns of adverse psychotropic effects. Canadian physicians endorse the need for a trial investigating the safety and efficacy of ketamine as a sedative for critically ill patients.

Lau, Michele P. X. L.; Low, Christopher J. W.; Ling, Ryan Ruiyang; Liu, Nigel S. H.; Tan, Chuen Seng; Ti, Lian Kah; Kofidis, Theo; MacLaren, Graeme; Ramanathan, Kollengode

doi: 10.1007/s12630-023-02620-1pmid: 37932652

PurposeWe aimed to conduct a systematic review and meta-analysis to assess the effects of anemia and anemia severity on patient outcomes in cardiac surgery and determine whether preoperative treatments confer postoperative benefit.SourceWe searched four international databases for observational and randomized studies published until 1 October 2022. Study quality was assessed via Newcastle–Ottawa scores and the Cochrane Risk-of-Bias 2 tool and certainty of evidence was rated with the Grading of Recommendations, Assessment, Development and Evaluations approach. We conducted random-effects meta-analyses for our primary outcome of mortality, for secondary outcomes including length of stay (LOS) in the hospital and intensive care unit, and for postsurgical complications. As part of a secondary analysis, we analyzed short-term preoperative anemia treatments and conducted trial sequential analysis of randomized trials to assess the efficacy of these treatment programs.Principal findingsWe included 35 studies (159,025 patients) in our primary meta-analysis. Preoperative anemia was associated with increased mortality (odds ratio [OR], 2.5; 95% confidence interval [CI], 2.2 to 2.9; P < 0.001, high certainty). Study-level meta-regression revealed lower hemoglobin levels and studies with lower proportions of male patients to be associated with increased risk of mortality. Preoperative anemia was also associated with an increase in LOS and postsurgical complications. Our secondary analysis (seven studies, 1,012 patients) revealed short-term preoperative anemia treatments did not significantly reduce mortality (OR, 1.1; 95% CI, 0.65 to 1.9; P = 0.69). Trial sequential analysis suggested that there was insufficient evidence to conclude if treatment programs yield any benefit or harm.ConclusionsPreoperative anemia is associated with mortality and morbidity after cardiac surgery. More research is warranted to test the efficacy of current anemia treatment programs.Study registrationPROSPERO (CRD42022319431); first submitted 17 April 2023.