*Professor of Anesthesia
†Resident in Anesthesia
‡Associate Professor of Urology
§Fellow in Urology
Received for publication August 30, 2000;
revised manuscript accepted for publication
January 10, 2001.
Morbid Obesity and the Prone
Position: A Case Report
Jay B. Brodsky, MD* Matthew Oldroyd, MD,†
Howard N. Winfield, MD,‡ Paul M. Kozlowski, MD,§
Departments of Anesthesia and Urology, Stanford University School of Medicine,
An improperly positioned prone patient can experience serious impairment of cardiopul-
monary function. However, with appropriate preparation, even an extremely obese patient
can safely tolerate the prone position. © 2001 by Elsevier Science Inc.
Keywords: Body mass index; obesity: morbid; patient positioning: prone.
A 37-year-old, 193 kg, 173 cm tall [body mass index (BMI) Ͼ 65 kg/m
was scheduled for percutaneous nephrolithotripsy. Her past medical history was
significant for hypothyroidism controlled with thyroid supplements, nephroli-
thiasis, urinary tract infections, and osteoarthritis. There was no history of
obstructive sleep apnea.
Preoperative physical examination revealed a Mallampati Class II view of the
oropharynx, full range of motion of her head and neck, a thyromental distance
of Ͼ5 finger breadths, and normal dentition. Vital signs, laboratory data, and
ECG were each within normal limits.
After premedication with Bicitra, metoclopramide, and famotidine, the
patient was brought to the operating room on a transport gurney. With the
patient supine and breathing room air, a radial artery catheter was placed to
allow arterial blood gas (ABG) sampling.
The patient was allowed to breath 100% O
by mask. Cricoid pressure was
applied, and intravenous sodium thiopental (500 mg IV) and succinylcholine
(140 mg IV) were administered. The patient’s trachea was easily intubated with
an 8.0 mm endotracheal tube (ETT) using a Macintosh #3 laryngoscope blade.
Her lungs were ventilated with 100% O
and isoflurane, with a tidal volume of
1000 mL at a rate of 6/min with an I:E ratio of 1:2. The peak inspiratory pressure
(PIP) was 30 cm H
Twelve people were needed to turn her prone onto two conventional
operating tables that had been placed side by side. Extra large pelvic and
shoulder bolsters were used (Figure 1). Care was taken to position her over the
bolsters to allow her abdomen to hang freely (Figure 2). All pressure areas were
In the prone position, the patient had bilateral equal breath sounds and
equal chest excursion. Inspired O
) and ventilator settings
were initially left unchanged, but the rate was increased from 6 to 8 breaths/min
during the procedure because of mild hypoventilation. Her PIP remained at 30
O with a tidal volume of 1000 mL. Several ABGs were obtained during the
Journal of Clinical Anesthesia 13:138–140, 2001
© 2001 Elsevier Science Inc. All rights reserved. 0952-8180/01/$–see front matter
655 Avenue of the Americas, New York, NY 10010 PII S0952-8180(01)00230-6