title: Evaluation of the ventilatory effects of the prone maximum restraint (PMR) position on obese human subjects.
abstract: The study sought to determine the physiologic effects of the prone maximum restraint (PMR) position in obese subjects after intense exercise. We designed an experimental, randomized, cross-over trial in human subjects conducted at a university exercise physiology laboratory. Ten otherwise healthy, obese (BMI>30) subjects performed a period of heavy exertion on a cycling ergometer to 85% of maximum heart rate, and then were placed in one of three positions in random order for 15min: (1) seated with hands behind the back, (2) prone with arms to the sides, (3) PMR position. While in each position, mean arterial blood pressure (MAP), heart rate (HR), minute ventilation (V˙E), oxygen saturation (SaO2), and end tidal CO2(etCO2) were measured every 5min. There were no significant differences identified between the three positions in MAP, HR, V˙E, or O2sat at any time period. There was a slight increase in heart rate at 15min in the PMR position over the prone position (95 vs. 87). There was a decrease in end tidal CO2 at 15min in the PMR over the prone position (32mmHg vs. 35mmHg). In addition, there was no evidence of hypoxia or hypoventilation during any of the monitored 15min position periods.
  
  
  CONCLUSIONS
  In this small study of obese subjects, there were no clinically significant differences in the cardiovascular and respiratory measures comparing seated, prone, and PMR position following exertion.
authors.affiliation: Department of Emergency Medicine, University of California, San Diego Medical Center, 200 W. Arbor Dr., MC-8676, San Diego, CA 92013-8676, United States. Electronic address: csloane@ucsd.edu.
authors.forename: Christian
authors.initials: C
authors.lastname: Sloane
authors.affiliation: Department of Emergency Medicine, University of California, San Diego Medical Center, 200 W. Arbor Dr., MC-8676, San Diego, CA 92013-8676, United States. Electronic address: tcchan@ucsd.edu.
authors.forename: Theodore C
authors.initials: TC
authors.lastname: Chan
authors.affiliation: School of Exercise and Nutritional Sciences, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-7251, United States. Electronic address: fred.kolkhorst@sdsu.edu.
authors.forename: Fred
authors.initials: F
authors.lastname: Kolkhorst
authors.affiliation: Department of Emergency Medicine, University of California, San Diego Medical Center, 200 W. Arbor Dr., MC-8676, San Diego, CA 92013-8676, United States. Electronic address: tneuman@ucsd.edu.
authors.forename: Tom
authors.initials: T
authors.lastname: Neuman
authors.affiliation: Department of Emergency Medicine, University of California, San Diego Medical Center, 200 W. Arbor Dr., MC-8676, San Diego, CA 92013-8676, United States. Electronic address: emcastillo@ucsd.edu.
authors.forename: Edward M
authors.initials: EM
authors.lastname: Castillo
authors.affiliation: Department of Emergency Medicine, University of California, San Diego Medical Center, 200 W. Arbor Dr., MC-8676, San Diego, CA 92013-8676, United States. Electronic address: gmvilke@ucsd.edu.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Vilke
mesh_terms: D000293:Adolescent; D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D018592:Cross-Over Studies; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology*; D010100:Oxygen / Q000097:blood; D005082:Physical Exertion / Q000502:physiology; D016684:Prone Position / Q000502:physiology*; D012123:Pulmonary Ventilation / Q000502:physiology; D011897:Random Allocation; D012149:Restraint, Physical; D013990:Tidal Volume / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: Asphyxia; Obese; Prone maximum restraint position; Restraint; Ventilation