P D Hansen

Oregon Health and Science University, Portland, Oregon, United States

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Publications (24)57.09 Total impact

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    ABSTRACT: BACKGROUND: The objective of our study was to assess the efficacy of multimodal hepatic cytoreduction in symptomatic patients with advanced hepatic metastases from carcinoid disease. METHODS: A retrospective analysis of prospectively collected data was performed. All consecutive patients, who underwent cytoreductive treatment for their metastatic carcinoid liver disease between October 1996 and October 2004, were enrolled. Treatment modalities included resection, radiofrequency with ethanol ablation, chemoembolization, or combined therapy. RESULTS: Fifteen patients, mean age 61 (SD 11) years, underwent cytoreduction. Twelve (80%) patients had extensive bilobar disease and 3 (20%) had solitary lesions. Eleven patients underwent one or more palliative surgical debulking procedures. Two patients had curative resection, and 2 patients had chemoembolization only due to unacceptable anesthesia risk. With a mean follow-up after 29 months (SD 22.1), 6 patients (40%) had stable disease, 8 (53.3%) had progression of disease and 1 (6.6%) had no disease at all. Death grasped 4 patients of which 2 died due to progression of disease. The median symptom relief period was 12 months. Overall survival was 57 months (mean) from the time of hepatic cytoreduction. CONCLUSIONS: Aggressive hepatic cytoreduction in patients with advanced metastatic carcinoid disease can achieve excellent overall survival but needs improvement in long-term symptom control. GRUNDLAGEN: Ziel dieser Studie ist es, die Wirksamkeit der Therapie der multimodaler Zytoreduktion in symptomatischen Patienten mit fortgeschrittenen hepatalen Karzinoidmetastasen zu erfassen. METHODIK: Es wurde eine retrospektive Analyse von prospektiv erhobenen Daten durchgeführt. Alle Patienten mit symptomatischem hepatal metastasierten Karzinoid, die zwischen Oktober 1996 und Oktober 2004 an unserer Klinik mittels Zytoreduktion behandelt wurden, wurden in diese Studie eingeschlossen. Die Behandlungsmethoden umfassten Leberresektion, Radiofrequenzablation, Äthanlinjektion, Chemoembolisation oder eine Kombination dieser Therapien. ERGEBNISSE: Es wurden insgesamt 15 Patienten mit einem mittleren Alter von 61 Jahren (±11 Jahre) mittels Zytoreduktion behandelt. Bei 12 Patienten (80%) lagen bilobäre multiple hepatale Metastasen vor, bei 3 Patienten (20%) handelte es sich um solitäre hepatale Läsionen. In 11 Patienten wurden eine oder mehrere palliative Leberresektionen durchgeführt. Bei zwei Patienten erfolgten kurative Resektionen und zwei weitere Patienten wurden mittels Chemoembolisation behandelt. Mit einer mittleren Nachbeobachtungszeit von 29 Monaten (±22,1 Monate) bestand bei 6 Patienten (40%) eine stabile Erkrankung, bei 8 Patienten kam es zu einem Fortschreiten und bei einem Patienten (6,6%) bestand kein Hinweis auf Rezidiv. Vier Patienten verstarben im Beobachtungszeitraum, zwei davon im Rahmen des Fortschreitens der Erkrankung. Die mediane Dauer der Symptomreduktion lag bei 12 Monaten. Die mittlere Überlebenszeit vom Zeitpunkt der Behandlung lag bei 57 Monaten. SCHLUSSFOLGERUNGEN: Mittels aggressiver Zytoreduktion lassen sich bei Patienten mit fortgeschrittenen hepatalen Karzinoidmetastasen zufriedenstellende Überlebenszeiten erzielen. Nichtsdestotrotz sind hinsichtlich der längerfristigen Symptomkontrolle Verbesserungen wünschenswert.
    European Surgery 01/2008; 40(2):72-76. · 0.15 Impact Factor
  • European Surgery-acta Chirurgica Austriaca - EUR SURG. 01/2008; 40(2):72-76.
  • K Thaler, J Garreau, P D Hansen
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    ABSTRACT: Early enteral tube feeding is widely used after major surgery and trauma. This article is intended to alert surgeons to the possibility of small bowel necrosis following enteral refeeding and to discuss etiology and clinical features. A case series from a single surgeon's database at a Tertiary Care Center is reported. Cases were drawnfrom a consecutive series of patients undergoing pylorus-preserving pancreaticoduodenectomy and placement of a needle catheter jejunostomy between January 1998 and June 2004. Two patients receiving early postoperative tube feeding developed sepsis with subsequent small bowel necrosis. Abdominal distension and signs of sepsis developed early postoperatively. Diagnosis was made based on characteristic computed tomography findings. Both patients underwent laparotomy with segmental bowel resection and survived. Non-specific septic symptoms associated with recurrent abdominal distension are ominous signs in patients receiving early postoperative enteral tube feeding and should prompt discontinuation of enteral nutrition. Within this scenario, CT imaging represents a valuable adjunct in the early assessment of these patients.
    Digestive Surgery 02/2005; 22(5):375-7. · 1.47 Impact Factor
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    N N Lee, R W O'Rourke, J Cheng, P D Hansen
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    ABSTRACT: Radiofrequency ablation (RFA) is an alternative for the treatment of unresectable hepatic tumors. Tumors beneath the diaphragmatic dome may be difficult to access by laparoscopy. In these cases, a transthoracic transdiaphragmatic approach for delivering RFA can be used. Three patients with hepatic metastatic disease were treated using a transthoracic transdiaphragmatic approach to deliver RFA therapy for tumors in liver segments 7 and 8. The patients underwent thoracoscopy. The tumors were identified using transdiaphragmatic ultrasound, and transthoracic transdiaphragmatic RFA (TTRFA) was performed. In three patients, TTRFA was successfully used to ablate five lesions. There were no perioperative complications, blood loss was minimal,and postoperative hospital stays ranged from 2 to 8 days. There were no recurrences during a follow-up period of 4 to 20 months. TTRFA is a viable alternative for hepatic tumors located beneath the dome of the diaphragm that are difficult to access by laparoscopy.
    Surgical Endoscopy 12/2004; 18(11):1672-4. · 3.43 Impact Factor
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    ABSTRACT: Totally extraperitoneal (TEP) repairs of inguinal hernias, despite having a favorable clinical outcome are often criticized due to higher costs and charges associated with this approach. We, therefore, present a comparison of direct costs and charges between TEP and open tension-free (OPN) repairs, emphasizing the effect of cost-containment measures on the part of surgeons and the hospital's charging (rate-setting) policies on these measurements. Itemized direct costs, charges, and reimbursements were determined for 41 TEP and 44 OPN unilateral repairs done between January 1997 and December 1999. Multiple sensitivity analyses were done to evaluate the effect of cost-containment measures and the hospital's rate-setting policies on the differences in costs and charges between the two procedures. The hospital's profits were expressed as profit-cost ratios. The mean direct cost for a TEP repair was $128.58 more than the OPN repair ($795.07[+/-65] vs 666.49 [+/-52]). However, mean charges and hospital reimbursement were $2,139.80 and $1,679.87, respectively, more for the TEP repairs. The profit-cost ratio was significantly higher in the TEP group (2.85:1 vs 1.07:1, P<.001). We found that 79.8% of the difference in direct costs vs 29% of the difference in charges between the two procedures was sensitive to cost-containment measures. Forty-five percent of the difference in charges was due to the hospital's nonuniform rate-setting policies. Long-term follow-up (38 months) showed no recurrence for either procedure. The direct cost of TEP repairs with the minimal use of disposable instruments in a high-volume center is comparable to the OPN repair. However, due to differences in the hospital's charging policies, TEP repair would appear to be an expensive alternative from the payer's point of view.
    Hernia 09/2004; 8(3):196-202. · 1.69 Impact Factor
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    ABSTRACT: Radiofrequency ablation (RFA) is rapidly evolving as an effective minimally invasive technique for the treatment of small and unresectable liver tumors. A potential cause of treatment failure is the inability to determine the optimum number of overlapping ablations needed to completely destroy tumors larger than the size of a single ablation. To clarify this relationship, we performed a mathematical evaluation that enables us to accurately estimate the number of ablations needed to completely ablate larger tumors. This estimation is based on the assumptions that complete ablation of the surface of a target tumor, including its blood supply, would completely destroy the tumor and that the tumor and ablations produced are perfectly spherical. The smallest possible number of partially overlapping ablations that would completely cover the surface of the target tumor is the same as the number of faces on a regular polyhedron that has a circumscribing diameter equal to or greater than the diameter of the target sphere. This mathematical analysis shows that for a 5-cm ablation device, tumors with diameters ranging between 3.01 and 3.30 cm will require at least four ablations. Tumors between 3.31 and 4.12 cm require six overlapping ablations, and tumors between 4.13 and 6.23 cm require 12 overlapping ablations. The number of ablations needed for larger tumors and for 3-, 4-, 6-, and 7-cm ablation devices are also determined. The smallest number of ablations required to completely ablate a spherical target tumor larger than the size of the ablation sphere increases dramatically as tumor size increases. Because this model is geometrically optimized, even a small change in the position of the ablation spheres with respect to the target sphere can leave potentially unablated tumor and thus result in treatment failure.
    Surgical Endoscopy 05/2004; 18(4):696-701. · 3.43 Impact Factor
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    ABSTRACT: Laparoscopic radiofrequency ablation (LRFA) and laparoscopic hepatic artery infusion pump (LHAIP) placement are new treatment options for patients with colorectal liver metastases. This study investigates the selection criteria, safety, efficacy, and preliminary outcomes of patients treated with LRFA and LHAIP placement. Fourty five patients with colorectal metastases confined to the liver, 37 of whom had failed systemic chemotherapy, were treated with LRFA and/or LHAIP between September 1996 and December 2001. Treatment selection was individualized, based on each patient's general health, liver function, and tumor size, number, location, and distribution. Twenty patients (44%) had LRFA alone, 10 (22%) had LHAIP placement alone, and 15 (33%) patients had combined LRFA and LHAIP therapy. The LRFA group had a significantly shorter mean operative time and blood loss (p <0.05), but hospital stays were similar when compared to patients receiving LRFA + LHAIP or LHAIP alone. Tumor characteristics were worse in both LHAIP groups, with a higher incidence of tumors >or=4 cm, major vascular involvement, diffuse tumor pattern, bilobar distribution, and involvement of more than three segments. During a mean follow-up period of 11.5 +/- 7.8 months (range, 1-38), the actuarial survival was 70%, 67%, and 50% for LRFA, LRFA + LHAIP, and LHAIP, respectively. LHAIP only patients had the shortest estimated mean survival time of the three groups by Kaplan-Meier survival curves (p = 0.001). LRFA and/or LHAIP placement are safe and feasible treatment options for the treatment of colorectal hepatic metastases. The choice of treatment for patients should be based primarily on tumor characteristics. Long-term studies, which will elucidate the role of these evolving treatments, are now under way.
    Surgical Endoscopy 04/2003; 17(1):61-7. · 3.43 Impact Factor
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    ABSTRACT: Introduction: Basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF) are important positive regulators of tumor growth and angiogenesis. This study was designed to assess the effect of bFGF and HGF infusion on tumor growth and metastases in a syngeneic, rat colon adenocarcinoma tumor model. Methods: Liver tumors were established in each of 21 BD9 rats via surgical, subcapsular implantation of a 1.0 mm3 piece of a subcutaneously grown DHD/K12/TRb tumor. Test groups were infused systemically with 5 μg/day/rat bFGF or 0.5 μg/day/rat HGF via osmotic pump; and controls received saline. At 28 days all animals were killed and examined. Tumor volume was calculated as π[a2 × b]/6, where a is shorter length and b the longer length. Liver and lung specimens were fixed in zinc formalin and embedded in paraffin for H&E staining and immunohistochemical study. Results: On histologic examination, tumor cells were seen to grow along blood vessel branches after infusion bFGF and HGF. Both VEGF and Flk-1 expression was strong cytoplasmic staining in cancer cells from hepatic, peritoneal and lung metastases. Conclusion: While both bFGF and HGF appear to induce an increase in tumor growth in this model, the effect of bFGF was marked. Similarly, HGF appeared to stimulate the development of distant metastases, though not reaching significance, while bFGF produced local and distant metastases with statistically significant increase in lung metastases. This rat colon adenocarcinoma cell line expressed VEGF and its receptor Flk-1. Further studies are required to evaluate the mechanism of tumor growth and metastasis stimulation. TABLE—ABSTRACT P8Control (n = 7)bFGF (n = 7)HGF (n = 6∗)P valueTumor volume (mm3)48.8 ± 17.685.1 ± 25.0†59.3 ± 26.9†
    Journal of Surgical Research - J SURG RES. 01/2003; 114(2):275-276.
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    Cheng J, Hansen PD, Swanstrom LL
    Chinese Journal of Minimally Invasive Surgery. 01/2002; 2(1):8-10.
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    ABSTRACT: Laparoscopic antireflux surgery is frequently denied to older patients with gastroesophageal reflux disease (GERD) because of a perceived higher operative complication rate, a decreased impact of the intervention on quality of life, and decreased cost effectiveness. This study compares disease severity, surgical outcomes, and impact on quality of life between elderly and young patients with GERD. Patients were selected from a prospectively maintained database of 1100 patients who underwent various laparoscopic esophageal procedures at our institution. Only patients having chronic intractable GERD and a minimum 6 months' follow-up were included in the study. Thirty elderly patients with a mean age of 71.2 years (SD +/- 5.6) were compared with a group of 30 younger patients (mean age, 43.9 +/- 12.8 years). Comparisons were made between subjective and objective outcomes, operative results, and health-related quality of life (HQRL) scores using SF-36 instruments. The preoperative symptom assessment scores presenting frequency of symptoms on a 0-4 scale), and preoperative pH and manometry data were comparable in the two groups. Elderly patients had significantly higher ASA (American Society of Anesthesiologists) scores. Each group demonstrated a significant improvement in the postoperative symptom assessment scores and the esophageal functional studies (p<0.05). However, no significant differences were found in terms of postoperative complications, postoperative hospital stay, postoperative symptom scores, Demeester scores, or the HRQL data. Laparoscopic antireflux surgery in elderly patients improves acid reflux and appears to be safe and effective as measured by postoperative testing in elderly and young patients.
    Surgical Endoscopy 01/2002; 16(1):25-30. · 3.43 Impact Factor
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    ABSTRACT: In a minority of patients undergoing antireflux surgery, an esophageal lengthening procedure is required to reduce the gastroesophageal junction (GEJ) below the esophageal hiatus. We evaluated risk factors associated with an irreducible GEJ to identify clinical features that were predictive of the need for a Collis gastroplasty in patients undergoing laparoscopic antireflux surgery. Patients who required a Collis gastroplasty during a laparoscopic antireflux procedure (defined as the inability to reduce the GEJ > 2.5 cm below the esophageal hiatus despite extensive mobilization of the mediastinal esophagus) were compared to a random sample of patients who did not have a Collis gastroplasty. Predictors of the need for an esophageal lengthening procedure were identified using logistic regression modeling. Risks were expressed as odds ratios (OR) and 95% confidence intervals (CI). Twenty patients who had a Collis gastroplasty were compared to 133 patients who had adequate esophageal length. The presence of a stricture (OR 3.0; 95% CI 1.0, 9.7), paraesophageal hernia (OR 3.5; 95% CI 1.3, 9.6), Barrett's esophagus (OR 3.7, 95% CI 1.3, 10.7), and re-do antireflux surgery (OR 6.4; 95% CI 2.0, 20.7) were associated with the need for gastroplasty. Patients with none of these factors were extremely unlikely to require a gastroplasty (OR 0.08; 95% CI 0.02, 0.34). Patients undergoing laparoscopic antireflux surgery who are at high risk of needing an esophageal lengthening procedure can be easily identified preoperatively using simple clinical characteristics.
    Surgical Endoscopy 12/2001; 15(12):1408-12. · 3.43 Impact Factor
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    ABSTRACT: Recently there has been interest in performing laparoscopic herniorrhaphies without the use of staples or tacks to fix the mesh. Although mesh fixation has been linked to an increased incidence of nerve injury and involves increased operative costs, many surgeons feel that fixation is necessary to reduce the risk of hernia recurrence. This study evaluates the outcomes of laparoscopic herniorrhapies performed with and without mesh fixation at our institution. We retrospectively evaluated our last 172 laparoscopic herniorrhaphies, which span a period of conversion from staple fixation to nonfixation of total extraperitoneal herniorrhaphies using systematic chart review and follow-up self-administered questionnaires. The outcomes assessed were the incidences of postoperative neuralgia and hernia recurrence. Adjustment for important prognostic factors was achieved using Cox regression for estimating the risk of recurrence, and multiple logistic regression for estimating the risk of neuropathic complications. Of 172 laparoscopic herniorrhaphies performed in 129 patients since July 1993, 105 were accomplished without mesh fixation, and 67 were performed with fixation of mesh to the abdominal wall. There were no significant differences in demographics between the two groups. A trend toward a higher incidence of neuropathic complications was observed in the mesh-fixation group (risk ratio [RR], 2.2; 95% CI, 0.5-10). A nonsignificant increased risk of hernia recurrence with fixation of mesh was observed (4.2 vs 1.6 per 100 hernia-years at risk; RR, 2.3; 95% CI, 0.4-13.10), but this finding may be associated with a selection bias with regard to giant hernia defects. Our data suggest that mesh fixation to the abdominal wall may be avoided in total extraperitoneal repairs without increasing the risk of hernia recurrence and neuropathic complications. The increased risk of recurrence observed with mesh fixation possibly results from selection bias. Large randomized controlled studies are needed to determine whether mesh fixation is truly related to neuropathic complications and the incidence of recurrence.
    Surgical Endoscopy 11/2001; 15(10):1102-7. · 3.43 Impact Factor
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    ABSTRACT: The rapid adoption of laparoscopic surgery since the late 1980s added tremendous complexity into the operating room (OR) environment. For each case, a plethora of additional equipment-including monitors, video equipment, wiring, tubing, and cords-had to be set up, prolonging OR turnover time and decreasing OR efficiency. In 1993, the concept of designated minimally invasive surgery (MIS) suites was introduced. MIS suites integrated monitors and video equipment into the OR on ceiling-mounted columns and moved the controls to a centralized nursing station. The overall effect of this innovation on OR efficiency has not been measured. Five RNs with varying degrees of MIS experience were instructed on video setup and put-away criteria and then timed while performing a set of standardized tasks. Each set of tasks was performed twice using a standardized surgery model. Differences in setup and put-away times between MIS suites and standard ORs were tested using the t-test for paired comparisons. The mean +/- standard deviation (SD) video setup times were 27.9 +/- 5.3 sec (MIS) and 254.3 +/- 54.0 sec (standard); the put-away times were 19.8 +/- 2.7 sec (MIS) and 222.3 +/- 26.0 sec (standard). The mean difference +/- standard error (SE) in both the setup (226.4 +/- 16.9 sec, p = 0.0001) and put-away times (202.5 +/- 8.6, p = 0.0001) were large and statistically significant. Using a simulation model, we have demonstrated that the use of a MIS suite reduces video setup and put-away time significantly, with the potential for significant associated cost savings. This provides just one justification for the high cost of building such "ORs of the future."
    Surgical Endoscopy 11/2001; 15(10):1140-3. · 3.43 Impact Factor
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    ABSTRACT: Some epidemiologic studies have identified cholecystectomy as a risk factor for pancreatic and biliary cancer. We compared the incidence of cancers of the pancreas, extrahepatic bile duct and ampulla of Vater before and after the widespread adoption of laparoscopic cholecystectomy in the United States in 1991, when the use of cholecystectomy increased dramatically. Compared with 1980 to 1991, there was no increase in the incidence of cancer of the pancreas (adjusted incidence rate ratio [IRR] 0.97, 95% confidence interval [CI] 0.94 to 0.99) or extrahepatic bile duct (IRR 0.80, 95% CI 0.74 to 0.87) during 1992 to 1996. There was a small increase in the incidence of ampullary cancer (IRR 1.14, 95% CI 1.03 to 1.26). We did not find clear evidence of a short-term increase in the incidence of cancers of the pancreas, bile duct, and ampulla of Vater, that was attributable to the increased use of cholecystectomy.
    The American Journal of Surgery 07/2001; 181(6):526-8. · 2.52 Impact Factor
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    ABSTRACT: Patients with metastatic colorectal cancer limited to the liver are candidates for regional chemotherapy with implantable hepatic artery infusion (HAI) pumps. The poor prognosis of these patients, and the requirement of a laparotomy for placement, has deterred many oncologists from referral for HAI pump implantation. Minimally invasive surgical techniques are particularly well suited for the task of HAI pump placement in patients who may not tolerate the additional physiologic stress of a major surgical intervention. Advances in laparoscopic techniques allow pumps to be implanted safely and effectively, replicating the well-described tenets of open pump placement. The principal steps of the operation include a thorough laparoscopic evaluation to exclude extrahepatic disease, complete vascular isolation of the hepatic and gastroduodenal arteries, ligation of aberrant hepatic vessels, secure cannulation of the gastroduodenal artery, and confirmation of complete hepatic perfusion without extrahepatic perfusion. We describe the procedure and briefly review our clinical experience. We believe that the benefits typically derived from minimally invasive approaches (less pain, fewer perioperative complications, shorter hospitalization, faster recovery, and potentially less immune suppression) will be seen in these patients as well. If so, a completely laparoscopic approach to regional treatment of the liver may extend survival and improve the quality of life of patients whose prognosis is poor regardless of treatment. Controlled trials will be required to evaluate the added value of a laparoscopic approach to the placement of the hepatic artery pump.
    Archives of Surgery 07/2001; 136(6):700-4. · 4.10 Impact Factor
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    ABSTRACT: Because the surgical treatment of achalasia is directed at the palliation of chronic symptoms, it is important to assess how surgery affects patients' health-related quality of life (HRQL). We evaluated upper gastrointestinal symptoms, satisfaction, and HRQL in 19 patients with achalasia before and after undergoing a laparoscopic Heller myotomy and partial fundoplication. HRQL was assessed using the Medical Outcomes Study 36-item short form health survey (SF-36). The mean age of the patients was 40 years (range 16 to 74), and 58% were men. After a median follow-up of 21 months (range 2 to 35), 12 of 16 patients were satisfied with the results of their surgery. Liquid and solid dysphagia scores were improved after surgery, and the prevalence of heartburn symptoms did not change. Although all the health concepts measured by the SF-36 instrument showed some improvement, statistically significant increases (on a 0 to 100 scale) were detected in physical functioning (11.1, P = 0.02), role-physical (25.0, P = 0.05), bodily pain (12.2, P = 0.01), vitality (13.7, P = 0.02), and social functioning (18.4, P = 0.02). Most aspects of HRQL improve after a laparoscopic Heller myotomy and partial fundoplication for achalasia.
    The American Journal of Surgery 06/2001; 181(5):471-4. · 2.52 Impact Factor
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    ABSTRACT: There are a variety of approaches to the diagnosis and treatment of common bile duct (CBD) stones in patients undergoing laparoscopic cholecystectomy (LC). Decision modeling was used to evaluate the cost-effectiveness of four strategies for managing CBD stones around the time of LC: (a) routine preoperative endoscopic retrograde cholangiopancreatography (ERCP) (preoperative ERCP), (b) LC with intraoperative cholangiography (IOC), followed by laparoscopic common bile duct exploration (LCDE), (c) LC with IOC, followed by ERCP (postoperative ERCP), and (d) expectant management (LC without any tests for CBD stones). Local hospital data were used to estimate costs. Cost-effectiveness was expressed in terms of the cost per case of residual CBD stones prevented (in excess of the cost of LC alone). Diagnostic test characteristics, procedure success rates, and adverse event probabilities were derived from a systematic review of the literature. Sensitivity analysis was used to explore the effect of uncertainty on the results of the model. LC alone was the least costly strategy, but it was also the least effective. Of the more aggressive strategies, LCDE and preoperative ERCP were associated with marginal costs of $5993.60 and $299,259.35, respectively, per case of residual CBD stones prevented. Postoperative ERCP was more costly and less effective than LCDE, but it had a lower cost-effectiveness ratio than preoperative ERCP when the prevalence of CBD stones was <80%. Compared to other common approaches, laparoscopic CBD exploration is a cost-effective method of managing CBD stones in patients who undergo LC. If expertise in LCDE is unavailable, selective postoperative ERCP is preferred over routine preoperative ERCP, unless the probability of CBD stones is very high (>80%).
    Surgical Endoscopy 02/2001; 15(1):4-13. · 3.43 Impact Factor
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    ABSTRACT: In the absence of randomized controlled trials that directly compare all of the modern methods of managing achalasia, decision analysis may help determine the optimal treatment strategy. Four strategies for the initial management of achalasia were compared using the following decision model: (1) laparoscopic Heller myotomy and partial fundoplication; (2) pneumatic dilatation; (3) botulinum toxin injection; and (4) thoracoscopic Heller myotomy. Probabilities of clinical events and utilities of health states were estimated using review of the medical literature and patient interviews. A recursive decision tree (Markov model) was used to simulate all the important outcomes of each initial treatment option, allowing for complications, relapses over time, and transitions between strategies when appropriate. After 10 years, laparoscopic Heller myotomy with partial fundoplication was associated with the longest quality-adjusted survival (quality-adjusted life years [QALY] = 7.41). The difference between this strategy and either pneumatic dilatation or botulinum toxin injection was small. Thoracoscopic Heller myotomy was associated with the poorest quality-adjusted survival (QALY = 7.15). Pneumatic dilatation was the favored strategy when the effectiveness of laparoscopic surgery at relieving dysphagia was less than 89.7%, the operative mortality risk was greater than 0.7%, or the probability of reflux after pneumatic dilatation was less than 19%. In a decision model, laparoscopic Heller myotomy with partial fundoplication is at least as effective as endoscopic approaches for managing achalasia symptoms. However, the differences are small enough that patient preferences and local expertise should be taken into consideration when tailoring a treatment plan for an individual patient.
    Journal of Gastrointestinal Surgery 01/2001; 5(2):192-205. · 2.36 Impact Factor
  • D R Urbach, P D Hansen
    Langenbeck s Archives of Surgery 11/2000; 385(6):436-9. · 1.89 Impact Factor
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    ABSTRACT: Based on retrospective, uncontrolled studies, it has been claimed that Nissen fundoplication should be performed over an esophageal bougie to minimize postoperative dysphagia. We hypothesized that a surgeon experienced in laparoscopic fundoplication will have similar rates of postoperative dysphagia whether or not an esophageal bougie is used. A patient and observer blinded, randomized, prospective clinical trial to assess the effect of intraoperative bougie use. A tertiary care teaching hospital that is a regional referral source for complex laparoscopic foregut surgical procedures. Three hundred thirty-six consecutive patients referred for laparoscopic fundoplication between March 1, 1996, and July 31, 1998, were evaluated for eligibility based on inclusion criteria and, if applicable, were offered randomization for fundoplication with or without a 56F bougie. One hundred seventy-one patients were enrolled in this study. All patients underwent laparoscopic Nissen fundoplication, 81 with a bougie (hereafter referred to as the bougie group) and 90 without a bougie (hereafter referred to as the no bougie group). Dysphagia severity and frequency were assessed by a blinded observer using a standardized scoring system. Incidence of complications related to the use or absence of a bougie, operative times, and postsurgical recovery was also assessed. The mean operating time was 148 minutes (range, 65-295 minutes). The overall operative morbidity was 9% (7. 4% in the bougie group and 11% in the no bougie group, P=.41). One esophageal injury (1.2%) occurred in the bougie group. The 30-day mortality was 0. Long-term dysphagia assessment was completed in 90% of patients, with a mean follow-up of 11 months. Overall, long-term postoperative dysphagia was present in 13 patients (17%) in the bougie group and 24 patients(31%) in the no bougie group (P=.047). Severe dysphagia occurred in 5% of patients in the bougie group and 14% in the no bougie group. This study confirms the dogma that use of a large-caliber stent during the creation of a fundoplication decreases the long-term incidence of dysphagia; albeit at the risk of injury from the introduction of a bougie.
    Archives of Surgery 10/2000; 135(9):1055-61; discussion 1061-2. · 4.10 Impact Factor

Publication Stats

554 Citations
57.09 Total Impact Points

Institutions

  • 1997–2005
    • Oregon Health and Science University
      • Department of Surgery
      Portland, Oregon, United States
  • 2001
    • Portland VA Medical Center
      Portland, Oregon, United States
    • University of Toronto
      • Institute of Health Policy, Management and Evaluation
      Toronto, Ontario, Canada