Faculty Bibliography

BACKGROUND: Bariatric surgery in super-obese patients (BMI >50 kg/m(2)) can be challenging because of difficulties in exposure of visceral fat, retracting the fatty liver, and strong torque applied to instruments, as well as existing co-morbidities. METHODS: A retrospective review of super-obese patients who underwent laparoscopic adjustable gastric banding (LAGB n=192), Roux-en-Y gastric bypass (RYGBP n=97), and biliopancreatic diversion with/without duodenal switch (BPD n= 43), was performed. 30 day peri-operative morbidity and mortality were evaluated to determine relative safety of the 3 operations. RESULTS: From October 2000 through June 2004, 331 super-obese patients underwent laparoscopic bariatric surgery, with mean BMI 55.3 kg/m(2). Patients were aged 42 years (13-72), and 75% were female. When categorized by operation (LAGB, RYGBP, BPD), the mean age, BMI and gender were comparable. 6 patients were converted to open (1.8%). LAGB had a 0.5%, RYGBP 2.1% and BPD 7.0% conversion rate (P=0.02, all groups). Median operative time was 60 min for LAGB, 130 min for RYGBP and 255 min for BPD (P<0.001, all groups). Median length of stay was 24 hours for LAGB, 72 hours for RYGBP, and 96 hours for BPD (P <0.001). Mean %EWL for the LAGB was 35.3+/-12.6, 45.8+/-19.4, and 49.5+/-18.6 with follow-up of 87%, 76% and 72% at 1, 2 and 3 years, respectively. Mean %EWL for the RYGBP was 57.7+/-15.4, 54.7+/-21.2, and 56.8+/-21.1 with follow-up of 76%, 33% and 54% at 1, 2 and 3 years, respectively. Mean %EWL for the BPD was 60.6+/-15.9, 69.4+/-13.0 and 77.4+/-11.9 with follow-up of 79%, 43% and 47% at 1, 2 and 3 years, respectively. The difference in %EWL was significant at all time intervals between the LAGB and BPD (P<0.004). However, there was no significant difference in %EWL between LAGB and RYGBP at 2 and 3 years. Overall perioperative morbidity occurred in 27 patients (8.1%). LAGB had 4.7% morbidity rate, RYGBP 11.3%, and BPD 16.3% (P=0.02, all groups). There were no deaths. CONCLUSION: Laparoscopic bariatric surgery is safe in super-obese patients. LAGB, the least invasive procedure, resulted in the lowest operative times, the lowest conversion rate, the shortest hospital stay and the lowest morbidity in this high-risk cohort of patients. Rates of all parameters studied increased with increasing procedural complexity. However, the difference in %EWL between RYGBP and LAGB at 2 and 3 years was not statistically significant

BACKGROUND: Medial collateral ligament injuries heal by a scar response. HYPOTHESIS: Increased hemorrhage at the site of medial collateral ligament injury improves healing. STUDY DESIGN: Controlled laboratory study. METHODS: Ninety-six mice were divided into two groups. Group 1 mice underwent knee medial collateral ligament transection with the opposite knee as a sham-operated control and group 2 animals additionally had 0.25 ml of tail cut blood pipetted to the medial collateral ligament transection site and sham-operated opposite knee. Ligament specimens were harvested at 3, 7, 21, and 28 days. RESULTS: Immunohistochemical analysis demonstrated peak macrophage counts at day 7 in all transected specimens. Macrophage counts were higher in group 2 than in group 1 at all time points, with a statistically significant increase of macrophages noted at day 7. In situ hybridization demonstrated increased collagen gene expression, with peaks at 7 and 28 days after transection. Group 2 animals showed increased gene expression at all time points as compared with group 1, with a statistically significant increase noted at 7 and 28 days. Biomechanical testing demonstrated progressive healing at each time point. At 28 days, the load to failure was 67% that of the sham-operated knee. CONCLUSIONS: This study suggests there is an increased healing response with bleeding at the ligament injury site. Clinical Relevance: Identification of the factors involved with increased healing may allow manipulation of the healing response in the clinical setting