Standardization of thyroid ultrasound reporting in the community setting decreases biopsy rates.

OBJECTIVE: With the rising incidence of thyroid cancer, a standardized approach to the evaluation of thyroid nodules is essential. Despite the presence of multiple national guidelines detailing evaluation and management of these nodules, significant variability exists in the information that is collected and reported to clinicians from diagnostic imaging. The aim of this study was to evaluate the impact of thyroid ultrasound standardization on thyroid cancer detection in a community practice setting. DESIGN: As part of a physician-driven quality improvement project, a multidisciplinary team created an electronic worksheet to be utilized by sonographers to capture suspicious findings based on societal guidelines and agreed on institutional criteria for recommending fine needle aspiration (FNA) of thyroid nodules. PATIENTS: For a one-year period prior to and after the intervention, all ultrasounds performed for suspected thyroid pathology, excluding patients undergoing follow-up imaging, were reviewed at two affiliated community hospitals served by a single radiology and pathology group. MEASUREMENTS: The number of fine needle biopsies recommended and performed, as well as the percentage of FNAs positive for malignancy were evaluated. RESULTS: A total of 608 and 675 ultrasounds were reviewed in pre- and post-standardization periods, respectively. Following standardization, there was a similar percentage of FNAs recommended (35% vs. 37%, p = .68), fewer FNAs per total ultrasounds performed (36% vs. 31%, p = .03), fewer FNAs performed when FNA was not explicitly recommended (9.9% vs. 2.8%, p = .000046) and an increased detection of cytology consistent with, or suspicious for, malignancy (5% vs. 11.5%, p = .0028). CONCLUSIONS: Standardization of thyroid imaging protocol and management recommendations can reduce the number of FNAs performed and increase the percentage of positive tests in a community setting.

Characterization of Pancreaticojejunal Anastomotic Healing in a Porcine Survival Model.

INTRODUCTION: Anastomotic leak after pancreaticoduodenectomy is the most important cause of postoperative morbidity and mortality. Histological studies of bowel anastomoses have provided valuable insights regarding causes of anastomotic failure. However, this crucial information is lacking for pancreatico-enteric anastomoses. METHODS: Pancreaticoduodenectomy was performed in a porcine model. Animals were survived up to 10 days and then the pancreatico-enteral anastomosis specimen was resected en bloc. Anastomotic bursting pressure was measured and histological sections of the anastomoses were examined. RESULTS: Six out of 8 animals had excellent healing of the anastomoses. One animal developed a clinically significant leak at the pancreaticoduodenal anastomosis (12.5%) and one animal had a subclinical duodeno-duodenal leak discovered on necropsy (12.5%). Both anastomoses that failed had a collagen-to-tissue ratio less than 40%. In contrast, none of the anastomoses with a ratio greater than 40% showed any evidence of disruption. CONCLUSION: Our results indicate that quantitative measurement of collagen deposition at the pancreatic anastomosis provides objective assessment of healing of the pancreatic anastomosis. A survival porcine model of pancreaticoduodenectomy results in a similar leak rate to published data on pancreaticoduodenectomy in humans and will be useful for future studies assessing novel pharmacologic or technical interventions aimed at improving outcomes.

Laparoscopic radiofrequency ablation for the management of colorectal liver metastases: 10-year experience.

BACKGROUND: Published results addressing the treatment of colorectal liver metastases (CRLM) with radiofrequency ablation (RFA) vary widely with local recurrence rates of 2-40% and 5-year survival of 14-55%. The goal of this study was to analyze our 10-year experience with laparoscopic RFA. METHODS: From January 2000 to July 2010, 130 patients underwent laparoscopic RFA for CRLM. Kaplan-Meier analysis was used to assess survival. Univariate and multivariate analysis were performed to identify factors associated with survival and recurrence. RESULTS: In this cohort, median survival was 40.4 months with 5-year survival of 28.8%. Overall, 9.2% of patients had a local recurrence (3.6% for tumors 3 cm or less). On univariate analysis, factors associated with decreased survival were BMI (P = 0.045), rectal primary (P = 0.005), and increased tumor size (P = 0.002). On multivariate analysis, increased tumor size (HR 1.29 [95% CI: 1.04-1.59]; P = 0.020) and bilobar disease (HR 2.06 [95% CI: 1.02-4.15]; P = 0.044) were associated with decreased survival. On univariate analysis, only BMI was found to be associated with disease recurrence (P = 0.025). CONCLUSIONS: Our data demonstrate that laparoscopic RFA can achieve a median survival of 40.4 months with a low local recurrence rate. Patients with tumors 3 cm or less have a decreased risk of local recurrence.

Real-time dynamics of nitric oxide shifts within the esophageal wall.

BACKGROUND: Currently, indirect evidence suggests that the neurotransmitter nitric oxide (NO) plays a crucial role in the genesis of aboral propagation of esophageal peristalses during swallowing. However, direct evidence in this regard currently is lacking. This study aimed to assess the feasibility of using NO-selective microprobes to detect real-time NO changes within the esophageal wall of North American opossums (Didelphis virginiana) during normal progressive esophageal peristalsis and induced esophageal dysmotility. METHODS: Six adult opossums of both sexes (mean weight, 2.28 +/- 0.41 kg) were included in the study. All had normal esophageal motility, as documented by water-perfused esophageal manometry. A calibrated carbon fiber NO-selective microelectrode (ISNOP30, ISNOP100) was placed within the smooth muscle portion of the esophageal wall, and changes in NO levels were measured as redox current in pico-amperes (pA) with the Apollo-4000 NO meter. The dynamics of NO in response to reflexive deglutition were assessed during both normal propagative peristalsis and abnormal esophageal contractions induced by intravenous (i.v.) administration of the neural NO synthase inhibitor L-nitro L-arginine methyl ester (L-NAME) and banding of the gastroesophageal junction (GEJ) for 4-weeks. RESULTS: During normal propagative esophageal peristalsis, a mean change of 2,158.85 +/- 715.93 pA was measured by the NO meter. Intravenous administration of L-NAME and chronic banding of the GEJ induced achalasia-like esophageal contractions. A significantly smaller change in levels of NO was detected within the esophageal wall during dysfunctional motility (331.94 +/- 188.17 pA; p < 0.001) than during normal propagative peristalsis (579 +/- 385 pA; p < 0.001). CONCLUSION: The results of this study indicate that carbon fiber NO-selective microprobes can successfully measure changes in the concentration of NO, an important inhibitory neurotransmitter, within the esophageal wall and that these preliminary data support the involvement of this crucial neurotransmitter in programming normal propagation of peristaltic waves within the esophagus.

Patient factors predictive of 24-h pH normalization following endoluminal gastroplication for GERD.

BACKGROUND: Endoluminal full-thickness gastroplication has been documented to provide significant and long-lasting improvement of GERD symptoms and health-related quality of life (HRQL) with very little patient morbidity. These treatments, however, are criticized for normalizing esophageal acid exposure in only 30-40% of patients treated. We hypothesize that there are objective criteria that will identify those patients who will have a normal DeMeester score (DMS) following endoluminal treatment. METHODS: Data from a prospective multicenter trial using the NDO Plicator device to treat GERD were available for statistical analysis. All patients were treated with endoluminal full-thickness gastroplication. All patients had GERD symptoms and abnormal 24-h pH exposure preoperatively. Postoperative objective outcome was assessed by performing 24-h pH studies at 6 months. Univariate and multivariate regression analyses were performed to determine factors predictive of successful treatment (normalized 24-h pH). RESULTS: A total of 266 patients were included in the study. Mean preoperative DMS was 47.91 (+/-31.34). Postoperatively, mean DMS decreased significantly (37.11 +/- 24.63, p < 0.001), and 31.67% of patients had a DMS within normal range (DMS < 22). Results of multivariate regression analysis demonstrated that the following preoperative patient characteristics were predictive of postoperative success (normal DMS): DMS < 30 (odds ratio [OR] = 4.24, 95% confidence interval [CI] = 1.73, 10.36, p < 0.001), heartburn score < 2 (OR = 3.37, CI = 1.44, 7.89, p = 0.005), and BMI < 30 (OR = 4.93, CI = 1.55, 15.61, p = 0.007). CONCLUSION: Data analysis from this prospective study indicates that the odds of objective success would be significantly greater if the treatment was restricted to thinner patients with mild reflux disease. This may help define the optimal place for endoluminal therapy in a comprehensive GERD treatment algorithm.

Chitosan hemostatic dressing for renal parenchymal wound sealing in a porcine model: implications for laparoscopic partial nephrectomy technique.

BACKGROUND AND OBJECTIVES: This study was to evaluate the feasibility of using a novel chitosan hemostatic dressing to control hemorrhage and urinary leakage by sealing off the parenchymal wound following LPN. METHODS: Nine heparinized domestic swine underwent bilateral laparoscopic partial nephrectomies involving either a polar or wedge resection. Estimated blood loss (EBL), hemostatic score, operative time, and adhesion score of the chitosan dressing were documented during LPN. Retrograde pyelography was performed to assess urinary leakage. RESULTS: Of 18 procedures, complete hemostasis after deployment of the chitosan dressing was successfully achieved in 17 of them. The hemostasis score improved significantly after the deployment in both polar (P<0.001) and wedge (P=0.017) resections. The rate of successful pyelocaliceal sealing was 85% (11/13) in polar and 60% (3/5) in wedge resections. Application of a bandage in wedge resections was fraught with greater difficulties in terms of number of applications required and prolonged operative time. However, the differences between this group and polar resection were not statistically significant. CONCLUSIONS: The chitosan hemostatic dressing is capable of being used in LPN procedures as a primary or supplemental material for controlling parenchymal hemorrhage and sealing the renal collecting system in the animal model.

Laparoscopic reintervention for failed antireflux surgery: subjective and objective outcomes in 176 consecutive patients.

HYPOTHESIS: Laparoscopy has become the standard approach for surgical treatment of uncomplicated gastroesophageal reflux disease. Laparoscopic reintervention following failure of primary antireflux surgery (ARS) remains controversial. The purposes of this study were to assess outcomes in patients operated on for failed ARS, to describe reasons for failure of the primary surgery, and to identify factors predictive of failure of the revision. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Tertiary-care teaching hospital. PATIENTS: A total of 176 patients (20 with multiple ARS) undergoing laparoscopic reintervention between September 12, 1993, and August 1, 2006, for failed ARS. INTERVENTIONS: Patients had preoperative subjective and/or objective documentation of failure after primary ARS: 131 patients had reoperative Nissen fundoplication, 28 patients had a partial wrap, and 17 patients had other procedures. MAIN OUTCOME MEASURES: Preoperative and postoperative symptom scores and results of objective studies were prospectively collected. Postoperative patients with symptom scores of 2 or greater and/or abnormal 24-hour pH study results (DeMeester score > 14.7) were considered to have treatment failures. Logistic regression was performed to identify variables significant for poor outcomes. RESULTS: Median follow-up was 9.2 months in 145 patients (82.4%). One hundred eight patients (74.5%) demonstrated excellent symptomatic outcomes (P = .001). Twenty of 37 patients with failures had reflux symptoms and 23 experienced dysphagia. Sixty-seven patients had 24-hour pH and manometry studies; 18 (11 asymptomatic) patients had a DeMeester score greater than 14.7. Odds of failure were higher among patients presenting with dysphagia (odds ratio, 3.38; 95% confidence interval, 1.35-8.40; P = .009) or requiring an esophageal-lengthening procedure (odds ratio, 5.77; 95% confidence interval, 1.38-24.11; P = .02). CONCLUSIONS: Laparoscopic reintervention following failed primary ARS provides excellent subjective and objective outcomes in most patients. Patients having laparoscopic reintervention for dysphagia relief or those requiring an esophageal-lengthening procedure have a significantly greater chance of a poor outcome.

Use of concentrated human albumin with argon-beam coagulation in laparoscopic partial nephrectomy.

PURPOSE: Laparoscopic partial nephrectomy (LPN) remains a technically challenging procedure mainly because of the lack of reliable methods of hemostasis. We evaluated the feasibility of using concentrated human albumin with argon-beam coagulation to control hemorrhaging and urinary leakage during LPN. MATERIALS AND METHODS: Six domestic swine underwent heparinization, then lower-pole LPN after renal-hilar vascular control had been obtained. The animals received argon-beam coagulation either alone (control) or with 38% albumin. Three days later, an identical procedure was performed on the contralateral kidney. Retrograde pyelography was employed to assess for urine leakage. The animals were then euthanized, and both kidneys were harvested for histologic examination. RESULTS: The mean operative and warm-ischemia times were similar in the two groups and were 27 and 15 minutes, respectively, using albumin with argon-beam coagulation and 25 and 16 minutes with argon coagulation alone. The albumin group required shorter coagulation times (187 v 312 seconds; P = 0.04), which resulted in less thermal injury. By retrograde pyelography, two kidneys (33%) in the albumin group and all six in the control group had urine leakage. CONCLUSIONS: Adding concentrated albumin to argon-beam coagulation substantially increases the reliability and durability of parenchymal repair after LPN. The time needed to achieve stable hemostasis and closure of the collecting system was reduced compared with standard argon-beam coagulation.

Laparoscopic Heller myotomy with Toupet fundoplication: outcomes predictors in 121 consecutive patients.

HYPOTHESIS: This study was performed to assess the intermediate-term outcomes after laparoscopic Heller myotomy and posterior Toupet fundoplication in a single-surgeon series with the expectation of identifying patient and disease factors associated with poor outcomes. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Tertiary care teaching hospital with a comprehensive esophageal physiology laboratory. PATIENTS: A total of 121 patients undergoing laparoscopic Heller myotomy with Toupet fundoplication (between December 1, 1996, and December 31, 2004) for achalasia were included. INTERVENTIONS: All patients had preoperative objective documentation of achalasia. A 5- to 6-cm-long myotomy was performed on the distal esophagus. The myotomy incision was extended 2 cm onto the stomach. A partial (270 degrees ) posterior Toupet fundoplication was performed as an antireflux mechanism in all patients. MAIN OUTCOME MEASURES: Data on preoperative and postoperative symptoms, manometry, and 24-hour ambulatory pH were prospectively collected. Symptoms were recorded with a standardized assessment tool. Patients with postoperative dysphagia scores of 2 or greater were considered treatment failure. Logistic regression modeling was performed to identify variables significant for poor outcomes. RESULTS: Preoperatively, 89 patients (73.6%) had severe dysphagia (dysphagia score, 3 or 4) and 32 patients (26.4%) had mild or moderate dysphagia (dysphagia score, 1 or 2). After a median follow-up period of 9 months, 102 patients (84.3%) (P<.001) had excellent relief of dysphagia (dysphagia score, 0 or 1). Eight additional patients (6.6%) demonstrated a significant (25%-75% [P=.01]) improvement in dysphagia scores. Only 11 patients (9.0%) had either no change or worse dysphagia. Postoperatively, all patients with manometry had a normal lower esophageal sphincter pressure (mean +/- SD, 14.7 +/- 6.6 mm Hg; P<.001) and good lower esophageal sphincter relaxation. Odds of failure were greatest for patients with severe preoperative dysphagia, male patients, and patients with classic amotile achalasia. Of the 60 patients having heartburnlike symptoms preoperatively (mean +/- SD score, 2.52 +/- 1.00), 19 (31.7%) continued to have similar symptoms after surgery. Sixteen (33.3%) of the 48 patients having postoperative pH studies demonstrated objective reflux (DeMeester score, >14.7). Five (31.2%) of these patients had symptoms of their reflux. CONCLUSIONS: Dysphagia improves in most patients after laparoscopic Heller myotomy with partial fundoplication. Patients with severe preoperative dysphagia, esophageal dilation, or amotile achalasia may have greater chances of a poor outcome.

Manometric abnormalities and gastroesophageal reflux disease in the morbidly obese.

BACKGROUND: Obesity is an epidemic in the USA. Many disorders are associated with obesity including gastroesophageal reflux disease (GERD). However, the prevalence of GERD and esophageal motility disorders in the morbidly obese population is unclear. METHODS: During evaluation for bariatric surgery, 61 morbidly obese patients underwent preoperative 24-hr pH and esophageal manometry. A single reviewer evaluated all 24-hr pH and manometric tracings. Johnson-DeMeester score >14.7 was considered diagnostic of GERD. Manometric criteria for motility disorders were from published values. All values are given as mean +/- SD. RESULTS: Mean age was 44.4 + 10.3 years. 55 of the patients (90%) were female. Mean BMI was 50.1 +/- 7.2 kg/m(2). 23 patients (38%) complained of GERD symptoms (reflux and/or heartburn). 1 patient (2%) complained of noncardiac chest pain. Mean Johnson-DeMeester score was 19.6 +/- 17.8. Mean intragastric and intrabolus pressures were both elevated (8.3 +/- 1.6 mmHg and 15 +/- 9 mmHg). 33 patients (54%) had abnormal manometric findings: 10 had a mechanically defective LES, 11 had a hypertensive LES, 2 had diffuse esophageal spasm, 3 had nutcracker esophagus,1 had ineffective esophageal disorder and 14 had nonspecific esophageal motility disorder. Some patients had more than one disorder. 20 patients (33%) had significantly elevated (>180 mmHg) contraction amplitudes at the most distal channel (210.0 +/- 28.7 mmHg). CONCLUSIONS: Prevalence of manometric abnormalities in the morbidly obese is high. Presence of a nut cracker-like distal esophagus in the morbidly obese is significant and warrants further evaluation.

Postoperative objective outcomes for upright, supine, and bipositional reflux disease following laparoscopic nissen fundoplication.

HYPOTHESIS: Traditionally, patients with gastroesophageal reflux disease fall into 3 categories based on 24-hour pH testing and the clinical occurrence of their acid exposure. Patients with upright reflux are believed to do worse following surgery compared with supine or bipositional reflux patients. We assessed objective postoperative outcomes for patients with upright, supine, and bipositional reflux following laparoscopic Nissen fundoplication to determine if there is a category of refluxing patient who should be counseled against antireflux surgery. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Esophageal physiology laboratory at a tertiary care teaching hospital. PATIENTS: A total of 225 patients (supine, 45; upright, 92; bipositional, 88) with preoperative and postoperative 24-hour pH measurements, manometry results, and standardized symptom assessment forms were included in the study. INTERVENTIONS: A Nissen fundoplication was performed based on 24-hour pH and manometry result. Esophageal manometry was performed with a water-perfused system, and 24-hour pH was measured with a digital capture device. MAIN OUTCOME MEASURES: Preoperative and postoperative symptom correlation, 24-hour pH, and manometric variables. RESULTS: There was a significant difference in preoperative symptom correlation between groups. Patients with bipositional reflux disease have significantly worst reflux disease (percentage of time with a pH <4, total number of reflux episodes, longest reflux episode, and Johnson-DeMeester score) and the weakest preoperative lower esophageal sphincter pressure. Postoperative symptom correlation was low among all 3 groups. There was no significant difference in postoperative 24-hour pH or manometry among groups. Success following surgery was achieved in 73.3% with supine reflux, 80.4% with upright reflux, and 75.0% with bipositional reflux. CONCLUSIONS: Patients with bipositional reflux have the most severe disease. Supine, upright, and bipositional reflux patients perform equally well following laparoscopic fundoplication as defined by objective outcome criteria.

Extended transmediastinal dissection: an alternative to gastroplasty for short esophagus.

HYPOTHESIS: The significance of short esophagus and its impact on failure after laparoscopic Nissen fundoplication are unknown. Although patients with severe esophageal shortening that requires Collis gastroplasty comprise a small percentage of patients undergoing fundoplication, we hypothesize that patients with moderate esophageal shortening requiring extended mediastinal dissection make up a larger subgroup and that extended laparoscopic mediastinal dissection is a good treatment strategy for such patients. DESIGN AND SETTING: Retrospective comparative analysis in an academic and private practice-based tertiary referral center. PATIENTS: A total of 205 patients underwent laparoscopic Nissen fundoplication for gastroesophageal reflux disease or paraesophageal hernias over 4 years. Outcomes in patients requiring either a type I (<5 cm) or type II (>5 cm) mediastinal dissection were compared. INTERVENTIONS: Laparoscopic Nissen fundoplication with or without extended mediastinal dissection and esophageal physiology testing. MAIN OUTCOME MEASURES: Symptom assessments, operative reports, and outcomes were prospectively recorded on standardized data sheets. Postoperative symptom assessment and esophageal physiology testing were performed. RESULTS: A total of 133 (65%) of the 205 patients underwent type I dissection, and 72 (35%) of the 205 patients underwent type II dissection. Failure occurred in 15 (11%) of 133 patients and 6 (10%) of 72 patients, respectively. The presence of a large hiatal or paraesophageal hernia predicted the need for type II dissection. CONCLUSIONS: No difference was seen in failure rates between patients who required a type II dissection and those who did not. This finding suggests that aggressive application of laparoscopic transmediastinal dissection to obtain adequate esophageal length may reduce fundoplication failure in patients with esophageal shortening and provide a success rate similar to that of patients with normal esophageal length. More liberal application of Collis gastroplasty in these patients is not warranted.

Postoperative symptoms and failure after antireflux surgery.

BACKGROUND: Outcomes in patients having surgery for gastroesophageal reflux disease are most commonly determined by symptomatic assessment. Objective testing is usually reserved for symptomatic patients. HYPOTHESIS: To evaluate the relationship between symptomatic and objective outcomes after antireflux surgery. DESIGN: Retrospective analysis of prospectively collected data. SETTING: A tertiary care teaching hospital with a comprehensive esophageal physiology laboratory. INTERVENTIONS: A 360 degrees (Nissen) fundoplication or a 270 degrees (Toupet) posterior fundoplication was performed based on esophageal motility. Twenty-four-hour pH monitoring was used as a gold standard for assessing postoperative acid reflux. PATIENTS: Two hundred nine consecutive patients with preoperative and postoperative symptomatic and objective testing performed between January 1, 1996, and June 15, 2001. MAIN OUTCOME MEASURES: Data on preoperative and postoperative symptoms, DeMeester scores, and esophageal motility were prospectively collected. Objective testing was performed after at least 6 months. RESULTS: The preoperative median DeMeester score was 50.0 (interquartile [IQ] range, 30.3-87.0). One hundred eighty patients had a Nissen and 29 patients had a Toupet fundoplication. After a median postoperative interval of 7.7 months (IQ range, 6.7-9.5 months), 174 patients (83.3%) had normal DeMeester scores (median, 2.2; IQ range, 0.8-5.0; P<.001). Of 58 patients (27.7%) who had reflux symptoms after surgery, only 17 (29.3%) had abnormal DeMeester scores (median, 36.9; IQ range, 748.4-20.0; P =.001). Eighteen (11.9%) of the 151 asymptomatic patients had abnormal DeMeester scores (median, 32.5; IQ range, 22.2-57.5; P =.006). CONCLUSIONS: There is poor correlation between postoperative reflux symptoms and actual reflux (abnormal DeMeester scores). Surgeons must be careful to define their terms when reporting success or failure rates after antireflux surgery. Routine use of medical therapy for suppressing postoperative gastroesophageal reflux disease symptoms is not supported by these data, and postoperative therapy should be based on objective testing only.

Electrical stimulation of the vagus nerve restores motility in an animal model of achalasia.

Esophageal peristalsis generally does not return to normal after surgical treatment of achalasia. Direct electrical stimulation of the vagus nerve is known to stimulate antegrade peristalsis in the normal esophagus; however, it is not known whether electrical stimulation will induce return of peristalsis once an achalasia-like disorder has been established. The objective of this study was to perform quantitive and qualitative measurements of motility during electrical stimulation of the vagal nerve in an animal model of achalasia. An already established and verified animal achalasia model using adult North American opossums (Didelphis virginiana) was used. Fifteen opossums were divided into three groups. Sham surgery was performed on three animals (group 1). In group 2 (n=6) a loose Gore-Tex band (110% of the esophageal circumference) was placed around the gastroesophageal junction to prevent relaxation of the lower esophageal sphincter during swallowing. In group 3 (n=6) a relatively tighter band (90% of the esophageal circumference) was used to further elevate the lower esophageal sphincter pressure. At 6 weeks, after manometric and radiolologic confirmation of achalasia, electrical stimulation of the esophagus was performed before and after removal of the band using a graduated square-wave electrical stimulus. Changes in esophageal neural plexi were assessed histologically. Pre- and postoperative manometric data were compared using standard statistical techniques. No difference was observed in esophageal characteristics and motility after sham surgery in group 1. Animals in group 2 demonstrated a vigorous variety of achalasia (high-amplitude, simultaneous, repetitive contractions), moderate esophageal dilatation, and degeneration of 40% to 60% of intramuscular nerve plexi. Animals in group 3 developed amotile achalasia with typical low-amplitude simultaneous (mirror image) contractions, severely dilated ("bird beak") esophagus, and degeneration of 50% to 65% of nerve plexi. Vagal stimulation in group 2 demonstrated a significant increase in the amplitude of contractions (P<0.001) and return of peristaltic activity in 49% of swallows before band removal. After band removal, all of the contractions were peristaltic. In group 3 vagal stimulation before and after removal of the band demonstrated a significant increase in amplitude of contractions (P<0.0001) but no return of propagative peristalsis before band removal, however, 44% of contractions were progressive in the smooth portion of the esophagus after removal of the band. Electrical stimulation of the vagus nerve improved the force of esophageal contractions irrespective of the severity of the disease; however, peristaltic activity completely returned to normal only in the vigorous (early) variety of achalasia. Removal of the functional esophageal outlet obstruction, as with a surgical myotomy, may be necessary to obtain significant peristalsis with vagal pacing in severe achalasia.

Outcomes of antireflux surgery in patients with normal preoperative 24-hour pH test results.

OBJECTIVE: Preoperative 24-hour pH testing is controversial in surgical patients who have symptomatic gastroesophageal reflux disease (GERD) and endoscopic evidence of esophagitis. The objective of this study was to compare the clinical outcomes of Nissen fundoplication for symptomatic reflux between patients with normal and abnormal preoperative pH testing. METHODS: Patients were selected from a prospective database of patients who underwent laparoscopic esophageal procedures between January 1997 and December 2001 at our institution. Only patients having typical symptoms of GERD (heartburn and/or reflux), preoperative pH testing, manometry, and endoscopy and who had at least 6 months of post-operative follow-up were included in the study. Fifteen patients had normal preoperative DeMeester scores (DMS) (median 11.4, range 3.3 to 14.7). These were compared with 208 consecutive patients having abnormal preoperative DMS (median 49.6, range 15.2 to 250). Logistic regression modeling was performed to identify variables significant for poor outcome. Differences between means were tested using appropriate parametric or nonparametric tests. RESULTS: There were no statistically significant differences in demographics, preoperative symptom score (mean 2.9 +/- 1.1 vs. 3.1 +/- 0.68, P = 0.30), or preoperative grade of esophagitis (P = 0.37) between the 2 groups. After a median follow-up of 8.8 months (range 6 to 36), 6 (40%) of the patients having normal preoperative DMS and 17 (8.1%) of the patients having abnormal preoperative DMS continued to have typical GERD symptoms (P <0.01, B error = 0.02). The most significant factor for poor outcome in the regression model was normal preoperative pH (odds ratio 9.02, P <0.01). CONCLUSIONS: Symptomatic GERD patients with normal preoperative 24-hour pH test results have significantly worse subjective outcomes after Nissen fundoplication compared with patients having abnormal preoperative pH test results. To minimize poor symptomatic outcomes after antireflux surgery, a policy of routine preoperative pH testing is advised.

Outcomes following laparoscopic choledochoduodenostomy in the management of benign biliary obstruction.

INTRODUCTION: With the advent of endoscopic retrograde choledochoduodenostomy, the need for choledochoduodenostomy to treat common bile duct obstruction is less common, but occasionally required. METHODS: Patients considered for laparoscopic choledochoduodenostomy secondary to benign conditions between 1999 and 2009 at a single institution were included. Charts were retrospectively reviewed for preoperative, operative, and long-term outcomes data. RESULTS: Twenty patients were identified; 15 with chronic choledocholithiasis causing benign biliary obstruction or chronic recurrent cholangitis, 3 with chronic relapsing pancreatitis, and 2 with distal common bile duct strictures. Mean operative time was 270 min. No major operative complications were reported. Five patients with severe adhesions or portal hypertension required conversion to laparotomy. Median hospital stay was 6 days (range, 2-32). Postoperatively, three (20%) patients completed laparoscopically and three (66.7%) patients converted to laparotomy had complications. In addition, one death due to myocardial infarction was reported 4 weeks after hospital discharge. With an average follow-up of 21 months, only one patient (5%) developed recurrent symptoms. CONCLUSION: Laparoscopic choledochoduodenostomy is a useful technique in patients with benign, refractory common bile duct obstruction. This technically demanding procedure is feasible; however, the associated comorbidities in this complex group of patients result in a relatively high complication rate.

Hepatic resection vs minimally invasive radiofrequency ablation for the treatment of colorectal liver metastases: a Markov analysis.

HYPOTHESIS: Current literature evaluating radiofrequency ablation (RFA) for treatment of colorectal liver metastases describes high-risk surgical candidates or patients with unresectable disease. This creates bias when comparing RFA and hepatic resection. A Markov analysis would define theoretical outcomes necessary for RFA to demonstrate equivalence to resection. DESIGN: A multistate Markov decision analytic model was constructed. Second-order Monte Carlo analysis was used to simulate a randomized controlled trial. Sensitivity analyses were performed to determine the projected outcomes necessary for RFA to achieve equivalence with resection. SETTING: Tertiary care teaching hospital. PATIENTS: A systematic review of published literature was performed, identifying studies involving patients with colorectal liver metastases treated with RFA or resection. Data were also included from a prospective database of patients undergoing laparoscopic RFA at our institution. INTERVENTIONS: Percutaneous or laparoscopic RFA and hepatic resection. MAIN OUTCOME MEASURES: Quality-adjusted life expectancy and quality of life-adjusted survival. RESULTS: The base-case analysis (60-year-old man) demonstrated a mean ± SD quality-adjusted life expectancy of 5.67 ± 0.71 years and a 5-year survival of 38.2% following resection. Based on current literature, the mean ± SD quality-adjusted life expectancy for RFA was 3.61 ± 0.49 years, with a 5-year survival of 27.2%. Sensitivity analyses demonstrated that RFA becomes the preferred strategy if the median disease-free survival reaches 1.42 years. When limited to patients from our institution with resectable lesions, the quality-adjusted life expectancy for RFA improved to a mean ± SD of 5.72 ± 0.50 years. CONCLUSIONS: Classical Markov analysis demonstrates that based on current literature, resection is superior to RFA in the treatment of colorectal liver metastases. When input is limited to laparoscopic RFA in patients with resectable lesions, projected 5-year survival is superior to that of hepatic resection.

Outcomes of Nissen fundoplication in patients with gastroesophageal reflux disease and delayed gastric emptying.

OBJECTIVE: To investigate the effect of delayed gastric emptying (DGE) on subjective and objective outcomes of gastroesophageal reflux disease following Nissen fundoplication with or without pyloroplasty. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Tertiary care teaching hospital. PATIENTS: A total of 141 consecutive patients considered for Nissen fundoplication who also had suspected DGE based on symptoms. INTERVENTIONS: Of 141 patients, 63 had a time to 50% emptying (T(1/2)) greater than 90 minutes; 47 of the 63 of these had severe DGE (T(1/2) > 150 minutes) and had Nissen fundoplication and pyloroplasty. Sixteen of the 141 with T(1/2) greater than 90 but less than 150 minutes and 78 with normal gastric emptying findings (n = 78) had Nissen fundoplication only. MAIN OUTCOME MEASURES: Postoperatively, patients with symptom scores greater than 2 and/or abnormal 24-hour pH values (DeMeester score >14.7) were considered to have had unsuccessful treatment. Gastroesophageal reflux disease outcomes were compared between groups 1 and 2. Finally, the outcomes of both groups were compared with a control cohort of 418 patients with Nissen fundoplication and no DGE symptoms (group 3). RESULTS: At the mean follow-up of 21 months, there were no differences between the 2 groups regarding relief of reflux symptoms (DGE group, 54 of 63 [85.7%] vs NGE group, 71 of 78 [91%]; P = .47) or objective control of acid reflux (DGE group, 33 of 39 [84.6%] vs NGE group, 41 of 51 [80.3%]; P = .78). Dyspeptic symptoms were improved in the DGE group (P < .001); however, the overall incidence remained higher than the NGE group (P = .01). Postoperatively, T(1/2) normalized in 88.23% (15 of 17) of patients. Postoperative objective outcomes were also no different between these groups and patients with Nissen fundoplication who did not have DGE symptoms (n = 418). CONCLUSIONS: Delayed gastric emptying does not affect outcomes of gastroesophageal reflux disease following Nissen fundoplication, but patients with DGE have more postoperative gas and bloat and/or nausea compared with patients with normal gastric emptying; this is mostly corrected by addition of a pyloroplasty.

Use of a chitosan-based hemostatic dressing in laparoscopic partial nephrectomy.

OBJECTIVES: An external chitosan-based hemostatic bandage has been used to control aggressive bleeding from traumatic injuries. This study was to evaluate the feasibility of using an internal chitosan dressing based on the external platform to control hemorrhage and urinary leakage by sealing off the parenchymal wound following Laparoscopic partial nephrectomy (LPN) in a porcine model. METHODS: Nine heparinized domestic swine underwent bilateral laparoscopic partial nephrectomies involving either a polar (N = 13) or wedge resection (N = 5) followed by treatment with the chitosan dressing. Estimated blood loss, hemostatic score, urinary leakage, operative time, and adhesion score of the chitosan dressing were recorded. RESULTS: Of the 18 procedures, 17 achieved complete hemostasis after deployment of the chitosan dressing. The hemostasis score improved significantly after the deployment in both polar (p < 0.001) and wedge (p = 0.017) resections. The rate of successful pyelocaliceal sealing was 85% (11/13) in polar resections and 60% (3/5) in wedge resections. CONCLUSION: The chitosan-based hemostatic dressing is effective as a primary or supplemental material for controlling parenchymal hemorrhage and sealing the renal collecting system following LPN in the animal model.