Ryan Rivers

Factors associated with operative outcomes in laparoscopic gastric bypass.

BACKGROUND Laparoscopic 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. STUDY DESIGN This 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. RESULTS Operative 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. CONCLUSIONS There 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.

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

BACKGROUND Intraoperative 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. METHODS 104 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. RESULTS The 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. CONCLUSION Prolonged pneumoperitoneum during laparoscopic gastric bypass significantly reduced intraoperative urine output but did not adversely alter postoperative renal function.

Comparison of postoperative hepatic function after laparoscopic versus open gastric bypass

BACKGROUND Pneumoperitoneum has been shown to reduce hepatic portal blood flow and alter postoperative hepatic transaminases. This study evaluated the changes in hepatic function after laparoscopic and open gastric bypass (GBP). METHODS Thirty-six morbidly obese patients were randomly assigned to undergo either laparoscopic (n = 18) or open (n = 18) GBP. Liver function tests--total bilirubin (T Bil), gamma GT (GGT), albumin, alkaline phosphatase (ALP), aspartate transferase (AST), alanine transferase (ALT)--and creatine kinase levels were obtained preoperatively and at 1, 24, 48, and 72 hours postoperatively. RESULTS The two groups were similar in age, sex, and body mass index. Albumin and ALP levels decreased while T Bil and GGT levels remained unchanged from baseline in both groups without significant difference between the two groups. After laparoscopic GBP, ALT and AST transiently increased by sixfold and returned to near baseline levels at 72 hours. After open GBP, ALT and AST transiently increased by fivefold to eightfold and returned to near baseline levels by 72 hours. Creatine kinase level was significantly lower after laparoscopic GBP than after open GBP at 48 and 72 hours postoperatively. There was no postoperative liver failure or mortality in either group. CONCLUSIONS Laparoscopic GBP resulted in transient postoperative elevation of hepatic transaminase (ALT, AST) but did not adversely alter hepatic function to any greater extent than open GBP. Creatine kinase levels were lower after laparoscopic GBP reflecting its lesser degree of abdominal wall trauma.

Duplex ultrasound assessment of femoral venous flow during laparoscopic and open gastric bypass.

Background: Pneumoperitoneum (PP) and the reverse Trendelenburg (RT) position have been shown to decrease femoral blood flow, resulting in venous stasis. However the effects of PP and RT on femoral venous flow have not been evaluated in morbidly obese patients undergoing laparoscopic gastric bypass (GBP). We analyzed the effects of PP and RT on peak systolic velocity and the cross-sectional area of the femoral vein during laparoscopic and open GBP. We further examined the efficacy of intermittent sequential compression devices in reversing the reduction of femoral peak systolic velocity. Methods: Thirty patients with a body mass index (BMI) of 40–60 were randomly allocated to under go either laparoscopic (n = 14) or open (n = 16) GBP. A duplex ultrasound examination of the femoral vein was performed at baseline, during PP and combined PP and RT in the laparoscopic group, and at baseline and during RT in the open group. The ultrasound exam was performed first without the use of sequential compression devices and then with the sequential compression devices inflated to 45 mmHg. Results: The two groups were similar in age, sex, BMI, and calf and thigh circumferences. During laparoscopic GBP, PP resulted in a 43% decrease in peak systolic velocity and a 52% increase in the cross-sectional area of the femoral vein; the combination of PP and RT decreased peak systolic velocity to 57% of baseline and increased the femoral cross-sectional area to 121% of baseline. During laparoscopic GBP, the use of sequential compression devices during PP and RT partially reversed the reduction of femoral peak systolic velocity, but femoral peak systolic velocity was still lower than baseline by 38%. During open GBP, RT resulted in a 38% reduction in peak systolic velocity and a 69% increase in the cross-sectional area of the femoral vein; the use of sequential compression devices during RT partially reversed these changes by increasing femoral peak systolic velocity by 26%; however, it was still lower than baseline by 22%. Conclusions: Pneumoperitoneum and reverse Trendelenburg position during laparoscopic and open GBP are independent factors for the development of venous stasis. Combining the reverse Trendelenburg position with pneumoperitoneum during laparoscopic GBP further reduces femoral peak systolic velocity and hence increases venous stasis. The use of sequential compression devices was partially effective in reversing the reduction of femoral peak systolic velocity, but it did not return femoral peak systolic velocity to baseline levels.

Microchimerism decades after transfusion among combat-injured US veterans from the Vietnam, Korean, and World War II conflicts.

BACKGROUND: Blood transfusion after traumatic injury can result in microchimerism (MC) of donor white cells (WBCs) in the recipient as late as 2 to 3 years postinjury, the longest prospective follow‐up to date. The purpose of this study was to determine how long transfusion‐associated MC lasts after traumatic injury.

Distinct roles of trauma and transfusion in induction of immune modulation after injury

BACKGROUND: Trauma and transfusion can both alter immunity, and while transfusions are common among traumatically injured patients, few studies have examined their combined effects on immunity.

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.