Bruce M. Wolfe

Comparison of pulmonary function and postoperative pain after laparoscopic versus open gastric bypass: A randomized trial

BACKGROUNDnImpairment of pulmonary function is common after upper abdominal operations. The purpose of this study was to compare postoperative pulmonary function and analgesic requirements in patients undergoing either laparoscopic or open Roux-en-Y gastric bypass (GBP).nnnSTUDY DESIGNnSeventy patients with a body mass index of 40 to 60 kg/m2 were randomly assigned to undergo laparoscopic (n = 36) or open (n = 34) GBP. The two groups were similar in age, gender, body mass index, pulmonary history, and baseline pulmonary function. Pulmonary function studies were performed preoperatively and on postoperative days 1, 2, 3, and 7. Oxygen saturation and chest radiographs were performed on both groups preoperatively and on postoperative day 1. Postoperative pain was evaluated using a visual analog scale and the amount of narcotic consumed was recorded. Data are presented as mean +/- standard deviation.nnnRESULTSnLaparoscopic GBP patients had significantly less impairment of pulmonary function than open GBP patients on the first three postoperative days (p < 0.05). By the 7th postoperative day, all pulmonary function parameters in the laparoscopic GBP group had returned to within preoperative levels, but only one parameter (peak expiratory flow) had returned to preoperative levels in the open GBP group. On the first postoperative day, laparoscopic GBP patients used less morphine than open GBP patients (46 +/- 31 mg versus 76 +/- 39 mg, respectively, p < 0.001), and visual analog scale pain scores at rest and during mobilization were lower after laparoscopic GBP than after open GBP (p < 0.05). Fewer patients after laparoscopic GBP than after open GBP developed hypoxemia (31% versus 76%, p < 0.001) and segmental atelectasis (6% versus 55%, p = 0.003).nnnCONCLUSIONnLaparoscopic gastric bypass resulted in less postoperative suppression of pulmonary function, decreased pain, improved oxygenation, and less atelectasis than open gastric bypass.

A comparison study of laparoscopic versus open gastric bypass for morbid obesity

BACKGROUNDnLaparoscopic Roux-en-Y gastric bypass (GBP) has been previously described, but a comparative study between laparoscopic and open GBP has not been reported. The purpose of this study was to compare surgical outcomes oflaparoscopic GBP with those of open GBP for treatment of morbid obesity.nnnSTUDY DESIGNnFrom August 1998 to September 1999, we prospectively collected outcome data on 35 patients with body-mass indices between 40 kg/m2 and 60 kg/m2 who underwent laparoscopic GBP. Demographics, operative data, perioperative complications, and weight losses were collected and compared with those obtained from a retrospective chart review of 35 patients with body-mass indices between 40 kg/m2 and 60 kg/m2 who underwent open GBP before August 1998.nnnRESULTSnAge, gender, preoperative body-mass index, preoperative comorbidity, and earlier abdominal surgery were similar in both groups. All laparoscopic operations were completed without conversion to laparotomy. Mean operative time, operative blood loss, length of intensive care stay, and length of hospital stay were significantly less after laparoscopic GBP than after open GBP (p<0.05). There was no 30-day mortality in either group. At 1-year followup, analysis of the percentage of excess body weight loss showed no significant difference between the two groups (p<0.05).nnnCONCLUSIONSnLaparoscopic Roux-en-Y gastric bypass is technically feasible and safe. Laparoscopic GBP confers the clinical benefits of laparoscopy and an initial weight loss similar to that of open GBP.

The Physiologic Effects of Pneumoperitoneum in the Morbidly Obese

Objective:To review the physiologic effects of carbon dioxide (CO2) pneumoperitoneum in the morbidly obese. Summary Background Data:The number of laparoscopic bariatric operations performed in the United States has increased dramatically over the past several years. Laparoscopic bariatric surgery requires abdominal insufflation with CO2 and an increase in the intraabdominal pressure up to 15 mm Hg. Many studies have demonstrated the adverse consequences of pneumoperitoneum; however, few studies have examined the physiologic effects of pneumoperitoneum in the morbidly obese. Methods:A MEDLINE search from 1994 to 2003 was performed using the key words morbid obesity, laparoscopy, bariatric surgery, pneumoperitoneum, and gastric bypass. The authors reviewed papers evaluating the physiologic effects of pneumoperitoneum in morbidly obese subjects undergoing laparoscopy. The topics examined included alteration in acid-base balance, hemodynamics, femoral venous flow, and hepatic, renal, and cardiorespiratory function. Results:Physiologically, morbidly obese patients have a higher intraabdominal pressure at 2 to 3 times that of nonobese patients. The adverse consequences of pneumoperitoneum in morbidly obese patients are similar to those observed in nonobese patients. Laparoscopy in the obese can lead to systemic absorption of CO2 and increased requirements for CO2 elimination. The increased intraabdominal pressure enhances venous stasis, reduces intraoperative portal venous blood flow, decreases intraoperative urinary output, lowers respiratory compliance, increases airway pressure, and impairs cardiac function. Intraoperative management to minimize the adverse changes include appropriate ventilatory adjustments to avoid hypercapnia and acidosis, the use of sequential compression devices to minimizes venous stasis, and optimize intravascular volume to minimize the effects of increased intraabdominal pressure on renal and cardiac function. Conclusions:Morbidly obese patients undergoing laparoscopic bariatric surgery are at risk for intraoperative complications relating to the use of CO2 pneumoperitoneum. Surgeons performing laparoscopic bariatric surgery should understand the physiologic effects of CO2 pneumoperitoneum in the morbidly obese and make appropriate intraoperative adjustments to minimize the adverse changes.

Three-Year Follow-up of a Prospective Randomized Trial Comparing Laparoscopic Versus Open Gastric Bypass

Objective:To analyze long-term weight loss, changes in comorbidities and quality of life, and late complications after laparoscopic and open gastric bypass. Summary Background Data:Early results from our prospective randomized trial comparing the outcome of laparoscopic versus open gastric bypass demonstrated less postoperative pain, shorter length of hospital stay, fewer wound-related complications, and faster convalescence for patients who underwent laparoscopic gastric bypass. Methods:Between May 1999 and March 2001, 155 morbidly obese patients were enrolled in this prospective trial, in which 79 patients were randomized to laparoscopic gastric bypass and 76 to open gastric bypass. Two patients in the laparoscopic group required conversion to open surgery; their data were analyzed within the laparoscopic group on an intention-to-treat basis. The 2 groups were well matched for body mass index, age, and gender. Outcome evaluation included weight loss, changes in comorbidities and quality of life, and late complications. Results:The mean follow-up was 39 ± 8 months. There were no significant differences in the percent of excess body weight loss between the 2 groups at the 3-year follow-up (77% for laparoscopic versus 67% for open). The rate of improvement or resolution of comorbidities was similar between groups. Improvement in quality of life, measured by the Moorehead-Ardelt Quality of Life Questionnaire, was observed in both groups without significant differences between groups. Late complications were similar between groups except for the rate of incisional hernia, which was significantly greater after open gastric bypass (39% versus 5%, P < 0.01), and the rate of cholecystectomy, which was greater after laparoscopic gastric bypass (28% versus 5%, P = 0.03). Conclusions:In this randomized trial with a 3-year follow-up, we found that laparoscopic gastric bypass was equally effective as open gastric bypass with respect to weight loss and improvement in comorbidities and quality of life. A major advantage at long-term follow-up for patients who underwent laparoscopic gastric bypass was the reduction in the rate of incisional hernia.

Incidence and outcome of anastomotic stricture after laparoscopic gastric bypass

Anastomotic stricture is a frequent complication after Roux-en-Y gastric bypass (GBP). We evaluated the frequency of anastomotic stricture following laparoscopic GBP using a 21 mm. vs. a 25 mm circular stapler for construction of the gastrojejunostomy and the safety and efficacy of endoscopic balloon dilation in the management of anastomotic stricture. We reviewed data on 29 patients in whom anastomotic strictures developed after laparoscopic GBP. All strictures were managed with endoscopic balloon dilation using an 18 mm balloon catheter under fluoroscopic guidance. Main outcome measures were the number of anastomotic strictures in patients in whom the 21 mm (vs. 25 mm) circular stapler was used to create the gastrojejunostomy, time interval between the primary operation and symptoms, complications of endoscopic balloon dilation, the number of patients with resolution of obstructive symptoms, and body weight loss. There were 28 females with a mean age of 39 years and a mean body mass index of 48 kg/ m2. Anastomotic stricture occurred significantly more frequently with the use of the 21 mm compared to the 25 mm circular stapler (26.8% vs. 8.8%, respectively; P<0.01). The median time interval between the primary operation and presentation of stricture was 46 days. After the initial dilation, recurrent stricture developed in 5 (17.2%) of 29 patients. These five patients underwent a second endoscopic dilation, and only one of these five patients required a third endoscopic dilation. None of the 29 patients required more than three endoscopic dilations. The mean percentage of excess body weight loss at 1 year for patients in whom the 21 mm circular stapler was used for creation of the gastrojejunostomy was similar to that for patients in whom the 25 mm circular stapler was used (68.2% vs. 70.2%, P = 0.8). In this series the rate of anastomotic stricture significantly decreased with the use of the 2 5 mm circular stapler for construction of the gastrojejunostomy without compromising weight loss. Endoscopic balloon dilation is a safe and effective option in the management of anastomotic stricture following laparoscopic GBP.

Effect of Intravascular Volume Expansion on Renal Function During Prolonged CO2 Pneumoperitoneum

OBJECTIVEnTo evaluate whether intravascular volume expansion would improve renal blood flow and function during prolonged CO2 pneumoperitoneum.nnnSUMMARY BACKGROUND DATAnAlthough laparoscopic living donor nephrectomies have a considerably reduced risk of complications for the donors, significant concerns exist regarding procurement of a kidney in the altered physiologic environment of CO2 pneumoperitoneum. Recent studies have documented adverse effects of CO2 pneumoperitoneum on renal hemodynamics.nnnMETHODSnRenal and systemic hemodynamics and renal histology were studied in a porcine CO2 pneumoperitoneum model. After placement of a pulmonary artery catheter, carotid arterial line, Foley catheter, and renal artery ultrasonic flow probe, CO2 pneumoperitoneum (15 mmHg) was maintained for 4 hours. Pigs were randomized into three intravascular fluid protocol groups: euvolemic (3 mLkg/hour isotonic crystalloid), hypervolemic (15 mL/kg/hour isotonic crystalloid), or hypertonic (3 mL/kg/hour isotonic crystalloid plus 1.2 mL/kg/hour 7.5% NaCl).nnnRESULTSnIn the euvolemic group, prolonged CO2 pneumoperitoneum caused decreased renal blood flow, oliguria, and impaired creatinine clearance. Both isotonic and hypertonic volume expansions reversed the changes in renal blood flow and urine output, but impaired creatinine clearance persisted.nnnCONCLUSIONSnIntravascular volume expansion alleviates the effects of CO2 pneumoperitoneum on renal hemodynamics in a porcine model. Hypertonic saline (7.5% NaCl) solution may maximize renal blood flow in prolonged pneumoperitoneum, but it does not completely prevent renal dysfunction in this setting. This study suggests that routine intraoperative volume expansion is important during laparoscopic live donor nephrectomy.

Multicenter prospective evaluation of laparoscopic antireflux surgery: Preliminary report

SummaryBackground. A prospective study of 116 patients undergoing laparoscopic antireflux surgery was undertaken in four centers in the United Kingdom and the United States.nMethods. Patients with a hiatal hernia (n=80) underwent total Rosetti-Hell fundoplication, whereas those without a hiatal defect (n=36) were treated by a partial fundoplication (Toupet). The follow-up period ranged from 3 to 24 months; median was 13 months.nResults. The median duration of the operations was 2.5 h. Intraoperative complications were encountered in 16 patients (14.0%) and conversion to laparotomy was necessary for esophageal perforation in one. The postoperative recovery of gastrointestinal function was rapid and the median hospital stay from the time of the operation to discharge was 2 days, range 1–10. A good symptomatic result (>70% reduction of preoperative symptom score) was observed in 106 patients (91%). There were no postoperative deaths but 15 patients (13.0%) developed complications in the immediate postoperative period.At 3 months, complete endoscopic healing of the esophagitis was observed in 65/92 patients (71%) and improvement by at least one grade was seen in 19 patients (21%). Twenty-four-hour pH monitoring, which was abnormal preoperatively in 93% of patients, was normal after surgery in 95%. There were 10 symptomatic failures (persistent reflux symptoms) and 14 patients (12%) developed adverse symptoms related to the procedure (gas-bloat 8, dysphagia 9, gastroparesis 1, explosive diarrhoea 1). Readmission to hospital within 3 months was necessary in 9 patients.nConclusions. Laparoscopic antireflux surgery can be performed with a low morbidity. In the short term, 83% of patients were rendered symptom free. These results are similar to those reported after the equivalent open operations.

Factors associated with operative outcomes in laparoscopic gastric bypass.

BACKGROUNDnLaparoscopic gastric bypass (GBP) is becoming a common approach for treatment of morbid obesity. We analyzed preoperative factors that may be associated with operative outcomes in laparoscopic GBP.nnnSTUDY DESIGNnThis prospective study evaluates 150 consecutive laparoscopic GBP procedures performed by a single surgeon. Preoperative factors were grouped into three categories: 1) patient-specific (gender, age, abdominal surgical history, smoking), 2) obesity-specific (body mass index, hypertension, diabetes, sleep apnea), and 3) procedure-specific (operative experience of the surgeon [75 cases or less versus more than 75 cases]). Length of operation (240 minutes or less versus more than 240 minutes), postoperative complications (yes versus no), major complications (yes versus no), reoperation (yes versus no), and length of hospital stay (4 days or less versus more than 4 days) were the operative outcomes considered. In this series all patients who had a major complication required a reoperation. Data were analyzed using univariate and multiple logistic regression analyses.nnnRESULTSnOperative experience of surgeon (75 cases or less) was associated with lengthy operative time (adjusted odds ratio [AOR], 3.8; 95% confidence interval [CI], 1.7 to 8.3), major complications (AOR, 15.0; 95% CI, 1.5 to 143.0), and a lengthy (more than 4 days) hospital stay (AOR, 4.5; 95% CI, 1.1 to 18.0). Higher patient age (50 years or more) was associated with more postoperative complications (AOR, 11.4; 95% CI, 3.0 to 43.1) and major complications (AOR, 7.6; 95% CI, 1.1 to 48.7). Male gender also was associated with more postoperative complications (AOR 5.2; 95% CI, 1.1 to 23.1). Obesity-related comorbidities, body mass index, past abdominal surgical history, and smoking had no statistical association with operative outcomes in this study.nnnCONCLUSIONSnThere is an association of clinical outcomes after laparoscopic GBP with the age and gender of the patient and the operative experience of the surgeon. An operative experience of more than 75 laparoscopic GBP cases was associated with decreases in operative time, length of hospital stay, and number of major complications.

Systemic stress response after laparoscopic and open gastric bypass

BACKGROUNDnThe magnitude of the systemic stress response is proportional to the degree of operative trauma. We hypothesized that laparoscopic gastric bypass (GBP) is associated with reduced operative trauma compared with open GBP, resulting in a lower systemic stress response.nnnSTUDY DESIGNnForty-eight patients with a body mass index of 40 to 60 were randomly assigned to laparoscopic (n = 26) or open (n = 22) GBP Blood samples were measured at baseline and at 1, 24, 48, and 72 hours postoperatively. Metabolic (insulin, glucose, epinephrine, norepinephrine, dopamine, ACTH, cortisol), acute phase (C-reactive protein), and cytokine (interleukin [IL]-6, IL-8, tumor necrosis factor [TNF]-alpha) responses were measured. Catabolic response was also measured by calculating the nitrogen balance at 24 and 48 hours postoperatively.nnnRESULTSnThe two groups of patients were similar in terms of age, gender, and preoperative body mass index. The mean operative time was longer for laparoscopic GBP than for open GBP (229 +/- 50 versus 207 43 minutes). After laparoscopic and open GBP, plasma concentrations of insulin, glucose, epinephrine, dopamine, and cortisol increased; IL-8 and TNF-alpha remained unchanged; and negative nitrogen balances occurred at 24 and 48 hours. There was no significant difference in these parameters between groups. Concentrations of norepinephrine, ACTH, C-reactive protein, and IL-6 levels also increased, but these levels were significantly lower after laparoscopic GBP than after open GBP (p < 0.05).nnnCONCLUSIONSnSystemic stress response after laparoscopic GBP is similar to that after open GBP, except that concentrations of norepinephrine, ACTH, C-reactive protein, and IL-6 are lower after laparoscopic than after open GBP. These findings may suggest a lower degree of operative injury after laparoscopic GBP.

Effect of prolonged pneumoperitoneum on intraoperative urine output during laparoscopic gastric bypass.

BACKGROUNDnIntraoperative oliguria is common during laparoscopic operations. The objective of this study was to evaluate the effects of prolonged pneumoperitoneum during laparoscopic gastric bypass (GBP) on intraoperative urine output and renal function.nnnMETHODSn104 patients with a body mass index between 40 and 60 kg/m2 were randomly assigned to laparoscopic (n = 54) or open (n = 50) GBP. Intraoperative urine output was recorded at 30-min intervals. Blood urea nitrogen and creatinine levels were measured at baseline and on postoperative days 1, 2, and 3. Levels of antidiuretic hormone, aldosterone, and plasma renin activity were also measured in a subset of laparoscopic (n = 22) and open (n = 24) GBP patients at baseline, 2 hours after surgical incision, and in the recovery room.nnnRESULTSnThe laparoscopic and open groups were similar in age, gender, and body mass index. There was no significant difference in amount of intraoperative fluid administered between groups (5.4 +/- 1.6 L, laparoscopic versus 5.8 +/- 1.7 L, open), but operative time was longer in the laparoscopic group (232 min versus 200 min, p < 0.01). Urinary output during laparoscopic GBP was 64% lower than during open GBP at 1 hour after surgical incision (19 mL versus 55 mL, p < 0.01) and continued to remain lower than that of the open group by 31-50% throughout the operation. Postoperative blood urea nitrogen and creatinine levels remained within the normal range in both groups. Serum levels of antidiuretic hormone, aldosterone, and plasma renin activity peaked at 2 hours after surgical incision with no significant difference between the two groups.nnnCONCLUSIONnProlonged pneumoperitoneum during laparoscopic gastric bypass significantly reduced intraoperative urine output but did not adversely alter postoperative renal function.