title: Cardiac function during laparoscopic vs open gastric bypass.
abstract: BACKGROUND
  Hypercarbia and increased intraabdominal pressure during prolonged pneumoperitoneum can adversely affect cardiac function. This study compared the intraoperative hemodynamics of morbidly obese patients during laparoscopic and open gastric bypass (GBP).
  
  
  METHODS
  Fifty-one patients with a body mass index (BMI) of 40-60 kg/m2 were randomly allocated to undergo laparoscopic (n = 25) or open (n = 26) GBP. Cardiac output (CO), mean pulmonary artery pressure (MPAP), pulmonary artery wedge pressure (PAWP), central venous pressure (CVP), heart rate (HR), and mean arterial pressure (MAP) were recorded at baseline, intraoperatively at 30-min intervals, and in the recovery room. Systemic vascular resistance (SVR) and stroke volume (SV) were also calculated.
  
  
  RESULTS
  The two groups were similar in terms of age, weight, and BMI. Operative time was longer in the laparoscopic than in the open group (p < 0.05). The HR and MAP increased significantly from baseline intraoperatively, but there was no significant difference between the two groups. In the laparoscopic group, CO was unchanged after insufflation, but it increased by 5.3% at 2.5 h compared to baseline and by 43% compared to baseline in the recovery room. In contrast, during open GBP, CO increased significantly by 25% after surgical incision and remained elevated throughout the operation. CO was higher during open GBP than during laparoscopic GBP at 0.5 h and at 1 h after surgical incision (p < 0.05). During laparoscopic GBP, CVP, MPAP, and SVR increased transiently and PAWP remained unchanged. During open GBP, CVP, MPAP, and PAWP decreased transiently and SVR remained unchanged. There was no significant difference in the amount of intraoperative fluid administered during laparoscopic (5.5 +/- 1.6 L) and open (5.6 +/- 1.7 L) GBP.
  
  
  CONCLUSIONS
  Prolonged pneumoperitoneum during laparoscopic gastric bypass does not impair cardiac function and is well tolerated by morbidly obese patients.
authors.affiliation: Department of Surgery, University of California-Davis Medical Center, 2221 Stockton Blvd., 3rd Floor, Sacramento, CA 95817, USA. ninh.nguyen@ucdmc.ucdavis.edu
authors.forename: N T
authors.initials: NT
authors.lastname: Nguyen
authors.forename: H S
authors.initials: HS
authors.lastname: Ho
authors.forename: N W
authors.initials: NW
authors.lastname: Fleming
authors.forename: P
authors.initials: P
authors.lastname: Moore
authors.forename: S J
authors.initials: SJ
authors.lastname: Lee
authors.forename: C D
authors.initials: CD
authors.lastname: Goldman
authors.forename: C J
authors.initials: CJ
authors.lastname: Cole
authors.forename: B M
authors.initials: BM
authors.lastname: Wolfe
mesh_terms: D000328:Adult; D015992:Body Mass Index; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects* / Q000379:methods; D005773:Gastroscopy / Q000009:adverse effects* / Q000379:methods; D006334:Heart Function Tests / Q000379:methods*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D010535:Laparoscopy / Q000009:adverse effects* / Q000379:methods; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D009767:Obesity, Morbid / Q000503:physiopathology*