Xuan-Mai T Nguyen

University of California, Irvine, Irvine, California, United States

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Publications (25)88.72 Total impact

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    ABSTRACT: Strategic laparoscopic surgery for improved cosmesis (SLIC) is a less invasive surgical approach than conventional laparoscopic surgery. The aim of this study was to examine the feasibility and safety of SLIC for general and bariatric surgical operations. Additionally, we compared the outcomes of laparoscopic sleeve gastrectomy with those performed by the SLIC technique. In an academic medical center, from April 2008 to December 2010, 127 patients underwent SLIC procedures: 38 SLIC cholecystectomy, 56 SLIC gastric banding, 26 SLIC sleeve gastrectomy, 1 SLIC gastrojejunostomy, and 6 SLIC appendectomy. SLIC sleeve gastrectomy was initially performed through a single 4.0-cm supraumbilical incision with extraction of the gastric specimen through the same incision. The technique evolved to laparoscopic incisions that were all placed within the umbilicus and suprapubic region. There were no 30-day or in-hospital mortalities or 30-day re-admissions or re-operations. For SLIC cholecystectomy, gastric banding, appendectomy, and gastrojejunostomy, conversion to conventional laparoscopy occurred in 5.3%, 5.4%, 0%, and 0%, respectively; there were no major or minor postoperative complications. For SLIC sleeve gastrectomy, there were no significant differences in mean operative time and length of hospital stay compared with laparoscopic sleeve gastrectomy; 1 (3.8%) of 26 SLIC patients required conversion to five-port laparoscopy. There were no major complications. Minor complications occurred in 7.7% in the SLIC sleeve group versus 8.3% in the laparoscopic sleeve group. SLIC in general and bariatric operations is technically feasible, safe, and associated with a low rate of conversion to conventional laparoscopy. Compared with laparoscopic sleeve gastrectomy, SLIC sleeve gastrectomy can be performed without a prolonged operative time with comparable perioperative outcomes.
    No preview · Article · Mar 2012 · Journal of Laparoendoscopic & Advanced Surgical Techniques
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    ABSTRACT: Esophagectomy can be associated with significant morbidity such as leaks and strictures. Preoperative gastric ischemic conditioning is a concept aimed at inducing an ischemic insult to the gastric fundus and cardia prior to esophagectomy, thus leading to improvement of gastric perfusion. This retrospective study compared outcome data from 81 patients who underwent esophagectomy after laparoscopic gastric ischemic conditioning with that from 71 patients who underwent esophagectomy without conditioning. Gastric ischemic conditioning consisted of laparoscopic division of the left gastric vessels ± the short gastric vessels. The time interval from gastric ischemic conditioning to esophagectomy ranged from 2 to 75 days. Main outcome measures included demographics, mean time interval between staging and esophagectomy, and the rate of leaks and strictures following esophagectomy. The two groups were comparable with respect to gender and age. In the gastric ischemic conditioning procedures, there were no conversions; the mean operative time was 57 ± 15 min, the mean length of hospital stay was 1.0 ± 1.1 days, and the rate of postoperative complications was 3.7%. The mean time interval between gastric ischemic conditioning and esophagectomy was 6.0 ± 5.4 days. There were no significant differences in the leak rate (11.1% for conditioning vs. 8.5% without conditioning) or stricture rate (29.6% for conditioning vs. 25.3% without conditioning) between the two groups. Laparoscopic gastric ischemic conditioning is feasible and safe. However, the use of gastric ischemic conditioning in this study did not alter the clinical rate of postoperative leaks and strictures.
    No preview · Article · Dec 2011 · Surgical Endoscopy
  • Allan Nguyen · Thomas Vo · Xuan-Mai T Nguyen · Brian R Smith · Kevin M Reavis
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    ABSTRACT: Transoral incisionless fundoplication is a new treatment for patients with gastroesophageal reflux disease. We present our initial experience with 10 patients undergoing this procedure with varying past surgical histories. All procedures were performed under general nasotracheal anesthesia. RAND-36 and Visual Analog Scale symptom scores were collected at pre and postoperative appointments for a mean of 9.2 months. The mean procedure time was 68 minutes. There were no intraoperative or postoperative complications. Patients with prior pancreaticoduodenectomy had observed reduced working space due to prior distal gastrectomy and required additional insufflation due to no pyloric resistance to insufflation of the small bowel. The patient with prior fundoplication required additional time and force for fastener penetration of the resultant scar from the partially disrupted fundoplication. All patients were discharged within 23 hours of the procedure. Throughout the follow-up period, patients reported gradual changes in medication requirements and symptom scores. There were no late complications. Transoral incisionless fundoplication is technically safe in well-selected patients including those with prior esophageal and gastric surgery.
    No preview · Article · Oct 2011 · The American surgeon
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    ABSTRACT: BACKGROUND: Laparoscopic adjustable gastric banding is gaining in popularity in the United States. Our objective was to examine the outcomes of laparoscopic adjustable gastric banding and the prevalence of band revision and explantation at academic medical centers. METHODS: Using the "International Classification of Diseases, 9th revision," diagnosis and procedure codes, data were obtained from the University Health System Consortium Clinical Database for all laparoscopic adjustable gastric banding procedures performed from 2006 to 2009. The outcome measures included demographics, length of hospital stay, perioperative morbidity, mortality, and the prevalence of band revision and explantation. RESULTS: A total of 10,151 laparoscopic gastric banding procedures were performed from January 2007 to December 2009. The mean length of stay was 1.2 days. The perioperative morbidity rate was 3.0%, and the in-hospital mortality rate was .03%. The prevalence of band revision was .76% and of band explantation was .87%. Compared with the outcome of primary gastric banding, gastric band revision or explantation was associated with a longer length of hospital stay, greater perioperative morbidity, and greater cost. CONCLUSION: Within the context of the 3-year period of analysis, laparoscopic gastric banding was associated with low perioperative morbidity and mortality and a low prevalence of band revision and explantation.
    No preview · Article · Sep 2011 · Surgery for Obesity and Related Diseases
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    ABSTRACT: Gastrointestinal leak is a dreaded complication after esophagectomy. Conventional treatments for leak include conservative therapy, surgical reoperation, and even complete gastrointestinal (GI) diversion. The aim of this study was to evaluate the impact of endoluminal stenting in the management of esophagogastric leak after esophagectomy. Data on 18 (11.3%) of 160 patients who developed postoperative leaks after minimally invasive esophagectomy were reviewed. Indications for esophagectomy included carcinoma (n = 14), Barrett's with high-grade dysplasia (n = 3), and benign stricture (n = 1). Neoadjuvant therapy was used in 57.1% of patients with carcinoma. The first nine patients underwent conventional treatments for leak whereas the latter nine patients underwent endoscopic esophageal covered stenting as primary therapy. There were 5 cervical and 13 intrathoracic anastomotic leaks. Main outcome measures included patient characteristics, types of treatment, length of hospital stay, morbidity, and mortality. Subjects were 16 males and 2 females with a mean age of 66 years. In the conventional treatment group, leaks were treated with neck drainage (n = 4), GI diversion (n = 2), and thoracoscopic drainage with or without repair or T-tube placement (n = 3). In the endoscopy group, all leaks were treated with endoscopic covered stenting with or without percutaneous drainage (n = 9). Control of leaks occurred in 89% of patients in the conventional treatment group vs. 100% of patients in the endoscopic stenting group. Three patients in the conventional treatment group (33%) required esophageal diversion compared to none of the patients in the endoscopy group. The 60-day or in-hospital mortality was 0% for both groups. In our clinical practice, there has been a shift in the management of esophagogastric anastomotic leaks to nonsurgical therapy using endoscopic esophageal covered stenting. Endoluminal stenting is a safe and effective alternative in the management of GI leaks.
    No preview · Article · Sep 2011 · Journal of Gastrointestinal Surgery
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    ABSTRACT: During the past decade, the field of bariatric surgery has changed dramatically. This study was intended to determine trends in the use of bariatric surgery in the United States. Data used were from the Nationwide Inpatient Sample from 2003 through 2008. We used ICD-9 diagnosis and procedural codes to identify all hospitalizations during which a bariatric procedure was performed for the treatment of morbid obesity between 2003 and 2008. Data were reviewed for patient characteristics, annual number of bariatric procedures, and proportion of laparoscopic cases. US Census data were used to calculate the population-based annual rate of bariatric surgery per 100,000 adults. The number of surgeons performing bariatric surgery was estimated by the number of members in the American Society for Metabolic and Bariatric Surgery. For the period between 2003 and 2008, the number of bariatric operations peaked in 2004 at 135,985 cases and plateaued at 124,838 cases in 2008. The annual rate of bariatric operations peaked at 63.9 procedures per 100,000 adults in 2004 and decreased to 54.2 procedures in 2008. The proportion of laparoscopic bariatric operations increased from 20.1% in 2003 to 90.2% in 2008. The number of bariatric surgeons with membership in the American Society for Metabolic and Bariatric Surgery increased from 931 to 1,819 during the 6 years studied. The in-hospital mortality rate decreased from 0.21% in 2003 to 0.10% in 2008. In the United States, the number of bariatric operations peaked in 2004 and plateaued thereafter. Use of the laparoscopic approach to bariatric surgery has increased to >90% of bariatric operations. In-hospital mortality continually decreased throughout the 6-year period.
    No preview · Article · Aug 2011 · Journal of the American College of Surgeons
  • Ninh T. Nguyen · Xuan-Mai T. Nguyen · Christian Elliott · Kevin Reavis

    No preview · Article · May 2011 · Surgery for Obesity and Related Diseases
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    Ninh T Nguyen · Xuan-Mai T Nguyen · John Lane · Ping Wang
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    ABSTRACT: Obesity is one of the most important modifiable risk factors for the prevention of type 2 diabetes. The aim of this study was to examine the prevalence of diabetes with increasing severity of obesity and the distribution of HbA1c levels in diabetics participating in the latest National Health and Nutrition Examination Survey (NHANES). Data from a representative sample of adults with diabetes participating in the NHANES between 1999 and 2006 were reviewed. The prevalence of diabetes and levels of fasting glucose, insulin, c-peptide, and HbA1c were examined across different weight classes with normal weight, overweight, and obesity classes 1, 2, and 3 were defined as body mass index (BMI) of <25.0, 25.0-29.9, 30.0-34.9, 35.0-39.9, and equal to 40.0, respectively. The distribution of HbA1c levels among adults with diabetes was also examined. There were 2,894 adults with diabetes (13.6%) among the 21,205 surveyed participants. Among the adults with diabetes, the mean age was 59 years, the mean fasting glucose was 155 ± 2 mg/dl, and the mean HbA1c was 7.2%; 80.3% of diabetics were considered overweight (BMI ≥ 25) and 49.1% of diabetics were considered obese (BMI ≥ 30). The prevalence of adults with diabetes increased with increasing weight classes, from 8% for normal weight individuals to 43% for individuals with obesity class 3; the distribution of HbA1c levels were considered as good (<7.0%) in 60%, fair (7.0-8.0%) in 17%, and poor (>8.0%) in 23%. The mean fasting glucose and HbA1c levels were highest for diabetics with BMI <25.0, suggesting a state of higher severity of disease. Mean insulin and c-peptide levels were highest for diabetics with BMI = 35.0, suggesting a state of insulin resistance. In a nationally representative sample of US adults, the prevalence of diabetes increases with increasing weight classes. Nearly one fourth of adults with diabetes have poor glycemic control and nearly half of adult diabetics are considered obese suggesting that weight loss is an important intervention in an effort to reduce the impact of diabetes on the health care system.
    Preview · Article · Mar 2011 · Obesity Surgery
  • Madhukar S Patel · Darren J Malinoski · Xuan-Mai T Nguyen · David B Hoyt
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    ABSTRACT: Data regarding pre-existing comorbidities is often poorly recorded in trauma registries, and reports of their impact on outcomes are conflicting. Additionally, many previous reports, when conducting data analysis, do not reliably account for differences in case and control cohorts. Our objective was to identify a subset of patients with reliable comorbidity and complication data in the National Trauma Data Bank (NTDB) in order to determine the impact of select chronic organ system dysfunction on morbidity and mortality using case-control methodology. We analyzed a refined dataset from NTDB 7.1 (2002 to 2006) containing admissions to Level 1 and 2 trauma centers, which specified using chart abstraction to document comorbidities and complications. Patients with a history of cirrhosis, dialysis, HIV, and warfarin therapy were compared with a 2:1 case-matched control group. Data regarding age; Injury Severity Score (ISS); ventilator, ICU, and hospital lengths of stay; complications; and mortality were obtained. Pearson's chi-square, Fisher's exact test, and the t-test were used to compare demographics and outcomes of each comorbidity group. A p value < 0.05 was considered significant. After case-control matching, pre-existing cirrhosis, dialysis, and warfarin therapy were found to be risk factors for both complications and mortality; HIV/AIDS was found to be a risk factor only for complications. Chronic hepatic failure, end-stage renal disease, immunodeficiency, and acquired coagulopathy are associated with higher resource use, complication rates, and mortality in a refined subset of NTDB patients.
    No preview · Article · Jan 2011 · Journal of the American College of Surgeons
  • Christian Elliott · Xuan-Mai T. Nguyen

    No preview · Article · Jan 2011
  • Ninh T Nguyen · Chirag Dholakia · Xuan-Mai T Nguyen · Kevin Reavis
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    ABSTRACT: Pyloroplasty is performed during esophagectomy to avoid delayed gastric emptying. However, studies have shown that gastric function is minimally impaired even without a pyloroplasty when a gastric tube rather than the whole stomach is used for reconstruction. The aim of this study was to evaluate outcomes of minimally invasive esophagectomy without performance of a pyloroplasty. We performed a retrospective review of 145 patients who underwent a minimally invasive esophagectomy. The 30-day mortality was 2.1 per cent with an in-hospital mortality of 3.4 per cent. Of the 140 patients with more than 90 days follow-up, 31 patients had a pyloroplasty and 109 patients did not. One (3.2%) of 31 patients with pyloroplasty versus six (5.5%) of 109 patients without pyloroplasty developed delayed gastric emptying. There was no significant difference in the leak rate between the two groups (9.7% vs. 9.6%, respectively). Total operative time was significantly shorter in the group without pyloroplasty (360 vs. 222 minutes with a pyloroplasty, P < 0.01). Patients with delayed gastric emptying responded well to endoscopic pyloric dilation or Botox injection. The routine performance of a pyloroplasty during minimally invasive esophagectomy can be safely omitted with a reduction in operative time and minimal adverse effects on postoperative gastric function.
    No preview · Article · Oct 2010 · The American surgeon
  • Ninh Nguyen · Xuan-mai Nguyen · Christian Elliott BS

    No preview · Article · Sep 2010 · Journal of the American College of Surgeons
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    ABSTRACT: 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. 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). 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. 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.
    No preview · Article · Sep 2010 · Surgery for Obesity and Related Diseases
  • Ninh T Nguyen · Johnathan Sloan · Xuan-Mai T Nguyen
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    ABSTRACT: Data from the available published literature support that laparoscopic gastric bypass and laparoscopic adjustable gastric banding are safe and effective bariatric procedures for the treatment of morbid obesity. Compared with gastric bypass, gastric banding is commonly associated with a shorteroperative time and length of hospital stay, and lower perioperative morbidity. However, the medium- and long-term weight losses were consistently and dramatically better after gastric bypass. The 2 preoperative factors predictive of poor weight loss in patients with gastric banding were male gender and patients with a BMI greater than or equal to 50 kg/m2. With this knowledge, the final decision regarding gastric bypass versus gastric banding will rely on an in-depth discussion between patients and surgeons with regard to perioperative and late complication data, long-term weight loss and variability of weight loss between the 2 operations, as well as the data regarding the rate for remission of comorbidities between the 2 operations. At the current time, there is ample evidence for surgeons and patients to make a well-informed decision with regard to which operation is best for the individual patient.
    No preview · Article · Sep 2010 · Advances in Surgery
  • Ninh T Nguyen · Xuan-Mai T Nguyen · Hossein Masoomi

    No preview · Article · Sep 2010 · Seminars in Thoracic and Cardiovascular Surgery
  • Ninh T Nguyen · Xuan-Mai T Nguyen · Chirag Dholakia
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    ABSTRACT: Gastric leak after sleeve gastrectomy can lead to significant morbidity and mortality. The aim of this study was to examine the safety and efficacy of endoscopic deployment of a covered esophageal stent in the management of leaks after sleeve gastrectomy. Three consecutive patients who underwent sleeve gastrectomy at outside institutions presented with leaks. All three patients underwent endoscopic placement of a covered stent. Additional procedures included laparoscopic or percutaneous drainage of abdominal collection(s). The patients were two women and one man, with a mean age of 34 years. One patient presented acutely at day 7 after the index operation and two patients presented late at 6 and 9 months, respectively. Two patients had proximal gastric leaks and one patient had a proximal gastric leak with a concomitant obstruction at the mid-aspect of the gastric sleeve. Endoscopic deployment of a covered stent was successful in all cases. There were no complications relating to the stent placement. The stent was removed at 6 weeks in two patients and at 4 months in one patient. The use of endoscopic stent was a safe and effective option in the management of leaks after sleeve gastrectomy.
    No preview · Article · May 2010 · Obesity Surgery

  • No preview · Article · May 2010 · Gastroenterology
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    ABSTRACT: 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. 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. 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). The inhibition of intraluminal pancreatic enzymes using enteroclysis with the serine protease inhibitor, NM, after hemorrhagic shock significantly improves the clinical outcome.
    No preview · Article · May 2010 · The Journal of trauma
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    ABSTRACT: Laparoscopic techniques in colon surgery reduce postoperative pain, length of hospital stay, and 30-day morbidity when compared with open surgery. The objective of this study was to determine the feasibility of a laparoscopic colectomy in patients who have previously undergone abdominal surgery. We performed a retrospective, single-institution review of laparoscopic colorectal procedures for benign or malignant pathology between October 2002 and September 2008. Our analysis included 55 patients who previously had laparoscopic, open, or a combination of procedures and subsequently underwent laparoscopic colorectal surgery. We observed a 14.5 per cent conversion rate (n = 8). Of the patients who had previous open procedures (n = 48 [87.3%]), the conversion rate was 16.7 per cent. Only one patient (12.5%) who had a history of only laparoscopic surgery required conversion. The highest conversion rate in our study was from patients who underwent a left colectomy (60%, n = 3/5), which was the only statistically significant factor found for conversion. Since the emergence of laparoscopy, use in colon and rectal surgery nationwide has been poor as a result of multiple factors, including a frequent history of abdominal surgery. Our experience shows that laparoscopic colorectal surgery in patients with prior intra-abdominal surgery can be completed with an acceptable conversion rate.
    No preview · Article · Oct 2009 · The American surgeon
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    ABSTRACT: Twenty-five to 30 per cent of hypotensive trauma patients require an emergent surgery, however, we have no reliable means to quickly determine that need. Our goal was to determine, via retrospective review, parameters available within minutes of arrival that predict the need for emergent surgery to control hemorrhage in hypotensive trauma patients. Inclusion criterion was initial systolic blood pressure (SBP) < 90 mm Hg in the emergency department (ED). Patients who were dead on arrival or underwent ED thoracotomy were excluded. Emergent surgery was defined as sternotomy, thoracotomy, laparotomy, or major neck vascular repair on day of admission. Potential clinical predictors were analyzed in a binary logistic regression model. Six hundred and thirty-nine hypotensive patients were identified and 193 excluded, leaving 446 with a mean age of 33 +/- 19 years and Injury Severity Score of 22 +/- 17. Thirty-two per cent suffered penetrating trauma, 30 per cent needed emergent surgery, and 19 per cent died. Independent predictors were: prolonged extrication (odds ratio (OR) 2.3), no loss of consciousness (OR 2.8), intubation (OR 1.7), central line placement (OR 1.7), and blood transfusion (OR 2.1, all P < 0.05). We concluded that hypotensive trauma patients without head injuries who require prolonged extrication, intubation, central venous access, and blood transfusion in the ED are more likely to need emergent surgery.
    No preview · Article · Oct 2009 · The American surgeon