RT Journal Article
SR Electronic
T1 The Correlation Between Esophageal and Abdominal Pressures in Mechanically Ventilated Patients Undergoing Laparoscopic Surgery
JF Respiratory Care
FD American Association for Respiratory Care
SP respcare.02287
DO 10.4187/respcare.02287
A1 Anees Sindi
A1 Tom Piraino
A1 Waleed Alhazzani
A1 Marcel Tunks
A1 Mazen Faden
A1 Jinhui Ma
A1 Lehana Thabane
A1 Maureen Meade
YR 2013
UL http://rc.rcjournal.com/content/early/2013/09/11/respcare.02287.abstract
AB BACKGROUND: Intra-thoracic pressure of patients undergoing laparoscopic surgery may be affected by intra-abdominal pressure during surgery. We investigated the relationship between intra-abdominal pressure (Pabd) and esophageal pressure (Pes) in mechanically ventilated patients undergoing laparoscopic surgery. METHODS: We prospectively studied 43 consenting patients over 18 years of age who were scheduled for elective laparoscopic surgery with plans for intra-operative intubation and paralysis. After establishing a good level of inter-observer agreement on Pes measurements, Pes was measured by one observer for each patient, using an esophageal catheter. Pabd and Pes were recorded before and after abdominal insufflation. We used regression analysis to model the relationship between Pabd and Pes. RESULTS: Patient age varied from 22 to 78 years, with a mean of 53.2 ±14.6 years. Body mass index (BMI) varied from 13.7 to 60.5 kg/m2, with a mean of 33.7 ± 10.5. Positive end-expiratory pressures (PEEP) were 5-7 cmH2O for 19 patients, and 0 cmH2O for the remainder. Most patients underwent gastric bypass surgery (n=11); others underwent hernia repair (n=9), colon resection (n=7), cholecystectomy (n=6), and various other surgeries (n=10). Using univariate analyses, baseline Pabd was significantly correlated with baseline Pes (estimate of model coefficient [95% CI]: 0.79 (0.36, 1.21); p = 0.001; R2 = 0.24), and so was BMI (0.29 (0.19, 0.40); p<0.001; R2 = 0.41). However, a multivariable analysis showed no significant correlation with baseline Pabd (0.10 (-0.46, 0.65); p = 0.73) while BMI remained highly significant (0.27 (0.11, 0.43); p = 0.001) with R2 of 0.40. Due to unexpected uniformity of abdominal inflation pressures (generally 20.4 cm H2O) during surgery, data was not amenable to assessing for correlation between changes in abdominal and esophageal pressures after inflation. CONCLUSION: There was a limited correlation between baseline Pes and Pabd in patients undergoing elective laparoscopic surgery, suggesting limited value of Pabd measurements in the management of mechanically ventilated patients.