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Paul D Hansen

Publications and source records attributed to Paul D Hansen.

15 recordsLinked to original sources
PubMed2005

The evolving role of staging laparoscopy in the treatment of colorectal hepatic metastasis.

HYPOTHESIS: Laparoscopy is an increasingly important tool in the staging and treatment of hepatic malignancies. This study evaluates the effect of staging laparoscopy (SL) using intraoperative ultrasonography (IOUS) on the regional treatment of isolated hepatic colorectal metastasis. DESIGN: Analytic cohort study. SETTING: Tertiary care center. PATIENTS: Consecutive patients who have a colorectal metastasis confined to the liver and selected for surgical regional treatment. INTERVENTIONS: All patients underwent preoperative evaluation followed by SL/IOUS. Operative plans were based on preoperative imaging and were either carried out or altered intraoperatively according to SL/IOUS findings. MAIN OUTCOME MEASURE: Effect of SL/IOUS on surgical management. RESULTS: Between September 1996 and May 2004 one hundred fifty-two SL/IOUSs were performed in 136 patients (77 males and 59 females), who had a mean (SD) age of 63 (11) years. Data sets were complete in 138 events. All patients had isolated hepatic disease as defined by preoperative computed tomography in 152 (100%) and positron emission tomography in 107 (70%). Staging laparoscopy/IOUS identified surgically untreatable disease in 34 events (25%) because of peritoneal metastases (n = 15), nodal involvement (n = 11), diffuse hepatic disease (n = 5), no identifiable disease (n = 2), and untreatable disease (n = 1). Laparoscopic treatment events included radiofrequency ablations (n = 78), hepatic artery pump implantations (n = 40), resections (n = 26), and combined procedures (n = 37). Overall, SL/IOUS changed the treatment plan in 66 (48%) of 138 of events. This includes 32 (23%) of 138 events in which SL/IOUS findings significantly altered the actual procedure performed relative to the preoperative plan. Three minor complications occurred in the SL/IOUS-only group with a mean (SD) hospital stay of 1.3 (1) days. CONCLUSION: In the regional management of isolated colorectal hepatic metastasis, SL/IOUS avoids unnecessary laparotomies and influences definitive surgical intervention in a substantial proportion of patients.

Aged↗
PubMed2005

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.

Adult↗
PubMed2004

Laparoscopic placement of hepatic artery infusion pumps: technical considerations and early results.

BACKGROUND: Laparoscopic hepatic artery infusion pump (LHAIP) placement is a novel treatment option for patients with colorectal liver metastases. This study investigates technical difficulties with regard to variant hepatic arteries and the preliminary outcomes for patients treated with LHAIP placement. METHODS: Between March 1998 and January 2003, 38 patients with colorectal metastases confined to the liver, 35 (92%) of who had prior systemic chemotherapy that failed, were treated with LHAIP. RESULTS: Twelve patients (32%) had LHAIP placement only, and 26 (68%) had pump placement combined with laparoscopic radiofrequency ablation (LRFA; 24 patients) and/or liver resection (2 patients). Variant hepatic arterial (HA) anatomy was present in 18 patients (47%). The presence of a variant HA did not increase pump complications, operative time, or blood loss (P >/=.20) or decrease the functional time of pump use (P =.91) in comparison with normal anatomy. In all patients with a variant HA, laparoscopic ligation of the variant vessel and/or cannulation of nongastroduodenal artery resulted in complete hepatic perfusion. Three misperfusions identified intraoperatively with use of methylene blue injection were corrected by laparoscopic ligation (two) or postoperative angioembolization (one). Postoperative pump radionuclide flow studies confirmed isolated hepatic artery infusion in all cases. There was a 13% pump-related complication rate. During a median follow-up of 11 months (0.5 to 35.5 months), the actuarial rate of overall survival was 47% and the estimated median survival time was 17.5 months. CONCLUSIONS: LHAIP placement is technically feasible, and variant HA is not associated with increased pump complications or decreased pump functional time.

Aged↗
PubMed2004

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.

Adult↗
PubMed2004

Expression of vascular endothelial growth factor and receptor flk-1 in colon cancer liver metastases.

BACKGROUND/PURPOSE: This study investigated vascular endothelial growth factor (VEGF) and flk-1 expression in hepatic metastases from colon carcinoma, and their associations with tumor angiogenesis, proliferation, and apoptosis. METHODS: Immunohistochemical studies were performed for VEGF/flk-1, Ki-67, p53, and bcl-2 expression, and microvessel density (MVD) in surgical specimens from 35 patients who underwent hepatectomy for colon cancer liver metastases between 1986 and 2001. RESULTS: VEGF and flk-1 were expressed mainly in the cytoplasm of tumor cells. High VEGF expression was associated with high flk-1 expression (P = 0.043). MVDs of less than 15 and 15 or more were found in 5 (14.3%) and 30 (85.7%) of 35 hepatic metastases, respectively. A Ki-67 index (KI) of 50% or more was detected in 33/35 (94.3%) of tumors, and 23 of these (65.7%) showed a KI of 85% or more. A KI of less than 50% was present in 2/35 (5.7%) of tumors. The expression of VEGF/flk-1 was related to elevated MVD (P < or = 0.026). VEGF was also associated with an increased KI (P = 0.025). Mutant p53 and bcl-2 expressions were detected in 26/35 (74.3%) and 17/35 (48.6%) of liver metastases, respectively. Mutant p53 was not related to VEGF/flk-1 expression, but bcl-2 was highly associated with flk-1 (P = 0.007). The incidences of high flk-1 expression and a KI of 85% or more were significantly higher in tumors which were both p53- and bcl-2-positive (93.3% and 73.3%) than in tumors which were negative for both (42.9% and 14.3%; P < or = 0.021). CONCLUSIONS: The VEGF-flk-1 system takes part in tumor angiogenesis, proliferation, and apoptosis in colon liver metastases. The bcl-2 pathway may upregulate VEGF activity via the flk-1 receptor. These findings are preliminary, requiring a larger sampling in order to elucidate the role of VEGF/flk-1 in metastatic colon cancer.

Adult↗
PubMed2004

Laparoscopic biliary reconstruction.

BACKGROUND: Biliary reconstruction represents a relatively untested frontier in laparoscopy. METHODS: Retrospective review of all patients who underwent laparoscopic biliary operations at Legacy Health System from 1998 to 2003. RESULTS: Seven patients underwent laparoscopic biliary reconstruction. Indications included benign calculous disease in 4 patients, benign stricture on 1 patient, choledochal cyst in 1 patient, and malignant biliary obstruction in 1 patient. Operations performed included choledochoduodenostomy, hepaticojejunostomy, stricturoplasty, choledochal cyst excision with hepaticojejunostomy, and cholecystojejunostomy. Median operative time was 300 minutes. Median hospital stay was 4 days. One perioperative complication of a bowel obstruction required reoperation. Median follow-up was 15 months. One patient died of metastatic cancer 8 months after surgery. All other patients are symptom free with no signs of stricture or recurrent biliary obstruction. CONCLUSIONS: Laparoscopic biliary reconstruction represents a viable treatment option in carefully selected patients.

Adult↗
PubMed2004

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.

Aged↗
PubMed2003

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.

Chi-Square Distribution↗
PubMed2003

Acute transanal evisceration of the small bowel: report of a case and review of the literature.

We report a patient who presented with rectal rupture and transanal evisceration, a rare entity with only 52 cases previously described in the world literature. Our case is the first to implicate sheer stress on the anterior rectum caused by postoperative adhesions as the major etiologic contributing feature. Moreover, this case is the third reported with chronic constipation without rectal prolapse as an additional preexisting contributory condition. A summary of the medical literature including etiology, treatment, and outcomes is presented.

Acute Disease↗
PubMed2003

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.

Animals↗
PubMed2003

Cohort study of surgical bypass to the gallbladder or bile duct for the palliation of jaundice due to pancreatic cancer.

OBJECTIVE: To compare patterns in mortality and the use of subsequent biliary drainage interventions (surgical, endoscopic, and percutaneous) associated with the different types of biliary bypass. SUMMARY BACKGROUND DATA: Surgical palliation of obstructive jaundice due to pancreatic cancer is often accomplished with an intestinal bypass to either the gallbladder or the bile duct. It is not known whether a gallbladder bypass, which is a simpler operation and more amenable to laparoscopic surgery, performs as well as a bypass to the bile duct. METHODS: The authors conducted a retrospective cohort study of 1,919 patients 65 years of age or older who had a surgical biliary bypass for pancreatic cancer diagnosed between 1991 and 1996 using Medicare claims data and the Surveillance, Epidemiology and End Results (SEER) database. RESULTS: At 1, 2, and 5 years, 7.5%, 17.4%, and 26.0% of 945 patients initially treated with a gallbladder bypass had additional biliary interventions, as compared with 2.9%, 11.0%, and 13.3% of 974 patients initially treated with a bile duct bypass. Patients who initially had a gallbladder bypass were 4.4 times as likely to have additional biliary surgery and 2.9 times as likely to have any subsequent biliary intervention as were patients who initially had a bile duct bypass. Median survival was longer following bile duct bypass. The adjusted hazard ratio for death associated with gallbladder bypass was 1.2. CONCLUSIONS: Compared to patients whose initial biliary bypass was to the bile duct, the risk of having one or more additional surgical, endoscopic, or percutaneous biliary drainage procedures is substantially greater in patients whose initial bypass was to the gallbladder.

Aged↗
PubMed2002

The effect of laparoscopy on survival in pancreatic cancer.

HYPOTHESIS: Exposure to laparoscopy influences survival in patients with unresected pancreatic cancer who have a diagnostic or staging surgical procedure. METHODS: We used the Surveillance, Epidemiology, and End Results Medicare-linked database to identify a cohort of persons 65 years and older, who were newly diagnosed with primary pancreatic cancer between 1991 and 1996 and who had a diagnostic laparoscopy or laparotomy during the course of their disease. Patients with a prior malignancy and those who had a pancreatic resection were excluded. We used proportional-hazards regression to adjust risk estimates for demographic factors, medical comorbidities, tumor characteristics, and the use of other treatment modalities. RESULTS: We identified 112 individuals with pancreatic cancer who had a laparoscopic procedure and 791 who had only conventional surgery. More patients who had laparoscopic surgery had distant metastases at diagnosis (67.9% vs 41.2%; P =.001). Median duration of survival in the laparoscopic surgery group was 4.8 months (95% confidence interval [CI], 4.1-6.8) compared with 5.3 months in the group that had only open surgery (95% CI, 4.9-5.6; P =.83). Compared with patients who only had a laparotomy, patients who had laparoscopic surgery did not have an increased rate of death when adjusted for the effects of age, sex, tumor size, grade, the presence of nodal and distant metastases at diagnosis, and the use of radiation, chemotherapy, therapeutic endoscopic retrograde cholangiopancreatography, and biliary and gastric bypass (adjusted hazard ratio, 0.93; 95% CI, 0.62-1.40). CONCLUSION: Exposure to laparoscopic surgery did not adversely affect survival in a cohort of elderly patients with pancreatic cancer who had a diagnostic procedure but no pancreatic resection.

Aged↗
PubMed2002

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.

Female↗