Johnathan A. Slone
University of California, Irvine
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Annals of Surgery | 2009
Ninh T. Nguyen; Johnathan A. Slone; Xuan-Mai T. Nguyen; Jaimee S. Hartman; David B. Hoyt
Background:Gastric bypass and adjustable gastric banding are the 2 most commonly performed bariatric procedures for the treatment of morbid obesity. The aim of this study was to compare the outcomes, quality of life, and costs of laparoscopic gastric bypass versus laparoscopic gastric banding. Study Design:Between 2002 and 2007, 250 patients with a body mass index of 35 to 60 kg/m2 were randomly assigned to gastric bypass or gastric banding. After exclusion, 111 patients underwent gastric bypass and 86 patients underwent gastric banding. Outcome measures included demographic data, operative time, blood loss, length of hospital stay, morbidity, mortality, early and late reoperation rate, weight loss, changes in quality of life, and cost. Treatment failure was defined as losing less than 20% of excess weight or conversion to another bariatric operation for failure of weight loss. Results:There were no deaths at 90 days in either group. The mean body mass index was higher in the gastric bypass group (47.5 vs. 45.5 kg/m2, respectively, P < 0.01) while the mean age was higher in the gastric band group (45 vs. 41 years, respectively, P < 0.01). Compared with gastric banding, operative blood loss was higher and the mean operative time and length of stay were longer in the gastric bypass group. The 30-day complication rate was higher after gastric bypass (21.6% vs. 7.0% for gastric band); however, there were no life-threatening complications such as leaks or sepsis. The most frequent late complication in the gastric bypass group was stricture (14.3%). The 1-year mortality was 0.9% for the gastric bypass group and 0% for the gastric band group. The percent of excess weight loss at 4 years was higher in the gastric bypass group (68 ± 19% vs. 45 ± 28%, respectively, P < 0.05). Treatment failure occurred in 16.7% of the patients who underwent gastric banding and in 0% of those who underwent gastric bypass, with male gender being a predictive factor for poor weight loss after gastric banding. At 1-year postsurgery, quality of life improved in both groups to that of US norms. The total cost was higher for gastric bypass as compared with gastric banding procedure (
Surgery for Obesity and Related Diseases | 2009
Ninh T. Nguyen; Xuan-Mai T. Nguyen; James B. Wooldridge; Johnathan A. Slone; John S. Lane
12,310 vs.
Archives of Surgery | 2010
Ninh T. Nguyen; Samuel F. Hohmann; Johnathan A. Slone; Esteban Varela; Brian R. Smith; David B. Hoyt
10,766, respectively, P < 0.01). Conclusions:Laparoscopic gastric bypass and gastric banding are both safe and effective approaches for the treatment of morbid obesity. Gastric bypass resulted in better weight loss at medium- and long-term follow-up but was associated with more perioperative and late complications and a higher 30-day readmission rate. There was a wide variation in weight loss after gastric banding with a small proportion of patients considered as treatment failure, and male gender was a predictive factor for poor weight loss.
Surgery for Obesity and Related Diseases | 2010
Ninh T. Nguyen; Johnathan A. Slone; Kevin M. Reavis
BACKGROUND Obesity is a well-known risk factor for the development of coronary heart disease (CHD). The aim of the present study was to examine the differences in the 10-year CHD risk with increasing severity of obesity in men and women participating in the latest National Health and Nutrition Examination Survey. METHODS Data from a representative sample of 12,500 U.S. participants in the National Health and Nutrition Examination Survey from 1999 to 2006 were reviewed. The Framingham risk score was calculated for men and women according to a body mass index (BMI) of <25.0, 25.0-29.9, 30.0-34.9, and ≥ 35.0 kg/m(2). RESULTS The prevalence of those with hypertension increased with an increasing BMI, from 24% for a BMI <25.0 kg/m(2) to 54% for a BMI of ≥ 35.0 kg/m(2). The prevalence of an abnormal total cholesterol level (>200 mg/dL) increased from 40% for a BMI <25.0 kg/m(2) to 48% for a BMI of ≥ 35.0 kg/m(2). The 10-year CHD risk for men increased from 3.1% for a BMI <25.0 kg/m(2) to a peak of 5.6% for a BMI of 30.0-34.9 kg/m(2). The 10-year CHD risk for women increased from .8% for a BMI <25.0 kg/m(2) to a peak of 1.5% for a BMI of ≥ 35.0 kg/m(2). Both diabetes and hypertension were independent risk factors for an increasing CHD risk. CONCLUSIONS The 10-year CHD risk, calculated using the Framingham risk score, substantially increased with an increasing BMI. An important implication from our findings is the need to implement surgical and medical approaches to weight reduction to reduce the effect of morbidity and mortality from CHD on the U.S. healthcare system.
Journal of Trauma-injury Infection and Critical Care | 2010
Hubert Kim; Darren Malinoski; Boris Borazjani; Madhukar S. Patel; Joseph Chen; Johnathan A. Slone; Xuan-Mai T. Nguyen; Earl Steward; Geert W. Schmid-Schonbein; David B. Hoyt
OBJECTIVE To compare the outcomes of Medicare beneficiaries who underwent bariatric surgery within 18 months before and after implementation of the national coverage determination (NCD) for bariatric surgery. DESIGN Analysis of the University HealthSystem Consortium database from October 1, 2004, through September 31, 2007. SETTING A total of 102 academic medical centers and approximately 150 of their affiliated hospitals, representing more than 90% of the nations nonprofit academic medical centers. PATIENTS Medicare and Medicaid patients who underwent bariatric surgery to treat morbid obesity. MAIN OUTCOME MEASURES Demographics, length of stay, 30-day readmission, morbidity, observed-to-expected mortality ratio, and costs. RESULTS A total of 3196 bariatric procedures were performed before and 3068 after the NCD. After the implementation of the NCD, the volume of gastric banding doubled and the proportion of laparoscopic gastric bypass increased from 60.0% to 77.2%. Patients who underwent bariatric surgery after the NCD benefited from a shorter length of stay (3.5 vs 3.1 days, P < .001) and lower overall complication rates (12.2% vs 10.0%, P < .001), with no significant differences in the in-hospital mortality rates (0.28% vs 0.20%). Among Medicare patients, there was a 29.3% reduction in the number of bariatric procedures performed within the first 2 quarters after the NCD. However, the number of procedures returned to baseline volume within 1 year and exceeded baseline volume after 2 years of the NCD. CONCLUSION The bariatric surgery NCD resulted in improved outcomes for Medicare beneficiaries without limiting access to care for individuals with medical disability.
Journal of Laparoendoscopic & Advanced Surgical Techniques | 2009
Ninh T. Nguyen; Johnathan A. Slone; Kevin M. Reavis; James Woolridge; Brian R. Smith; Ken Chang
BACKGROUND Laparoscopic gastric banding is commonly performed using 5-6 abdominal trocars with enlargement of the largest trocar for implantation of the subcutaneous port. The aim of the present study was to compare the outcomes of conventional laparoscopic gastric banding with those of gastric banding performed through a single or duel incision. METHODS From April 2008 to May 2009, 23 patients underwent laparoscopic gastric banding through a single, 3.5-4.5-cm incision with implantation of the port through the same incision. The 2 study cohorts were matched for age, gender, and body mass index. The outcome measures included the operative time, blood loss, need for conversion to 5-trocar laparoscopy, and perioperative morbidity. RESULTS Each group included 6 men and 17 women. No significant differences were found between the 2 groups with regard to preoperative body mass index (40 versus 39 kg/m(2)), operative time, blood loss, or length of hospital stay. Of the 23 patients in the single incision group, 3 (13%) required conversion to conventional 5-trocar laparoscopy. No intraoperative or postoperative complications developed in either group. CONCLUSION The present results have shown that in a subset of patients with a lower body mass index, adjustable gastric banding performed through a single laparoscopic incision is technically feasible and safe and does not prolong the operative time. The procedure can be performed with mostly existing ports, laparoscopic instrumentation, and visualization platforms. A prospective randomized trial is necessary to determine the clinical advantages of this less-invasive technique.
Obesity Surgery | 2007
Ninh T. Nguyen; Marcelo W. Hinojosa; Johnathan A. Slone; John G. Lee; Vishal Khiatani; Samuel E. Wilson
BACKGROUND Recent studies suggest that intraluminal pancreatic enzymes play a major role in the initiation of the inflammatory cascade by the gut after hemorrhagic shock. Previous animal models have shown that the inhibition of enteral pancreatic enzymes with a serine protease inhibitor, nafamostat mesilate (NM), decreases leukocyte activation and transfusion requirements after hemorrhagic shock. The objective of this study was to determine whether enteroclysis with NM would improve the clinical outcomes in swine after hemorrhagic shock and intestinal hypoperfusion. METHODS Thirty-three male Yucatan minipigs weighing 25 kg to 30 kg underwent a controlled hemorrhage of 25 mL/kg with mesenteric clamp for further gut ischemia. Animals were allocated to three groups: (1) shock only (n = 15), (2) shock + enteroclysis with 100 mL/kg GoLYTELY (GL) as a carrier (n = 11), and (3) shock + enteroclysis with GL + 0.37 mmol/L NM (GL+NM, n = 7). Animals were resuscitated, recovered from anesthesia, observed for 3 days, and graded on a daily 4-point clinical scoring system. A score of 0 indicated a moribund state or early death, and a score of 4 indicated normal behavior. RESULTS Pigs treated with GL + NM had significantly higher mean postoperative recovery scores (3.8 +/- 0.4, essentially normal behavior with no early deaths) compared with animals within the shock only and shock + GL groups (2.1 +/- 1 with one early death and 2.2 +/- 1.2 with two early deaths, respectively, analysis of variance p < 0.003). CONCLUSION The inhibition of intraluminal pancreatic enzymes using enteroclysis with the serine protease inhibitor, NM, after hemorrhagic shock significantly improves the clinical outcome.
Archive | 2009
Ninh T. Nguyen; Johnathan A. Slone; Xuan-Mai T. Nguyen; Jaimee S. Hartman; David B. Hoyt
BACKGROUND Single-site laparoscopic surgery and natural orifice transumbilical surgery (NOTUS) have become exciting areas of surgical development. However, most reported case series consist of basic laparoscopic procedures, such as cholecystectomy and appendectomy. In this paper, we present the case of an advanced laparoscopic operation-construction of a gastrointestinal anastomosis-that was performed through ports placed entirely within the umbilicus. METHODS In this paper, we describe a 61-year-old male with a history of advanced pancreatic carcinoma who was referred with a gastric outlet obstruction. A laparoscopic gastrojejunostomy bypass, using a linear stapler with suture closure of the enterotomy, was performed through three abdominal trocars placed entirely within the umbilicus. Some potential advantages of NOTUS palliative gastrojejunostomy include reduced postoperative pain and the lack of visible abdominal scars. RESULTS The operation was completed uneventfully in 40 minutes. The patient recovered without complications and was discharged on postoperative day 2. At 1-month follow-up, the patient had improved oral intake without any further vomiting symptoms. CONCLUSION This case report documents the feasibility of an advanced anastomotic gastrojejunostomy procedure which can be performed through a single site. However, benefits of this approach, compared to conventional laparoscopic procedures, will require a prospective randomized clinical trial.
American Surgeon | 2009
Ninh T. Nguyen; Johnathan A. Slone; James B. Wooldridge; Brian R. Smith; Kevin M. Reavis; David B. Hoyt
Surgery for Obesity and Related Diseases | 2009
Ninh T. Nguyen; Johnathan A. Slone; Brian R. Smith; Kevin M. Reavis