Diagnosis of Type-I hiatal hernia: a comparison of high-resolution manometry and endoscopy.

Sliding Type-I hiatal hernia is commonly diagnosed using upper endoscopy, barium swallow or less commonly, esophageal manometry. Current data suggest that endoscopy is superior to barium swallow or esophageal manometry. Recently, high-resolution manometry has become available for the assessment of esophageal motility. This novel technology is capable of displaying spatial and topographic pressure profiles of gastroesophageal junction and crural diaphragm in real time. The objective of the current study was to compare the specificity and sensitivity of high-resolution manometry and endoscopy in the diagnosis of sliding hiatal hernia in patients with gastroesophageal reflux disease. Data were analyzed retrospectively for 83 consecutive patients (61% females, mean age 52 ± 13.2 years) with objective gastroesophageal reflux disease who were considered for laparoscopic antireflux surgery between January 2006 and January 2009 and had preoperative high-resolution manometry and endoscopy. Manometrically, hiatal hernia was defined as separation of the gastroesophageal junction >2.0 cm from the crural diaphragm. Intraoperative diagnosis of hiatal hernia was used as the gold standard. Sensitivity, specificity and likelihood ratios of a positive test and a negative test were used to compare the performance of the two diagnostic modalities. Forty-two patients were found to have a Type-I sliding hiatal hernia (>2 cm) during surgery. Twenty-two patients had manometric criteria for a hiatal hernia by high-resolution manometry, and 36 patients were described as having a hiatal hernia by preoperative endoscopy. False positive results were significantly fewer (higher specificity) with high-resolution manometry as compared with endoscopy (4.88% vs. 31.71%, P= 0.01). There were no significant differences in the false negative results (sensitivity) between the two diagnostic modalities (47.62% vs. 45.24%, P= 0.62). Analysis of likelihood ratios of a positive and negative test demonstrated that high-resolution manometry is better than endoscopy both to rule out and rule in a hiatal hernia. A significant discordance was also observed between the two tests (P= 0.033). High-resolution manometry has better specificity and ability to rule out an overt Type-I sliding hiatal hernia (greater likelihood ratio of a positive test) in patients with GERD. Because of high false negative results, both high-resolution manometry and endoscopy are unreliable for ruling in a hiatal hernia. Negative result for a hiatal hernia by either modality mandates additional testing.

Developing essential tools to enable transgastric surgery.

Natural orifice transluminal endoscopic surgery (NOTES) is a largely theoretical but potentially exciting evolution of minimally invasive surgical care. Using technology borrowed from current diagnostic and therapeutic flexible endoscopy, the idea is to replicate current laparoscopic procedures in an "incisionless" manner. It is widely recognized that for NOTES to become a practical reality, many issues need to be resolved, both methodologic and political. One critical element of development will be the design of appropriate instrumentation for NOTES. This is currently happening and involves a complex collaboration between industry and clinicians both to adapt current equipment and to design and create new tools to enable the performance of transluminal procedures. This article describes the current process of such technology development as well as the resulting instrumentation that enables the performance of NOTES. The issues of access and platform stability, laparoscopic-like instruments, and secure tissue approximation are described, and the devices to solve these issues are detailed.

Comparison of five different abdominal access trocar systems: analysis of insertion force, removal force, and defect size.

Trocar designs have evolved in response to concerns about complication rates and surgical ergonomics. Functional properties of trocar systems that can be objectively measured include insertion force, removal force and the size of the tissue defect. This study will evaluate these properties in 5 common trocar designs. A porcine model was used to evaluate five different trocar systems for insertion force, removal force, and functional and measured tissue defect. Insertion force was lowest for cutting trocars and highest for radially dilating trocars. Removal force was similar for all trocars. Functional and measured tissue defect size was smallest for the hybrid type and radially dilating trocars. An ideal trocar system incorporates a low insertion force, secure retention, and a minimal tissue defect. Of the systems we tested, the hybrid type trocar has similar wound characteristics to the radially dilating trocar with the benefit of reduced insertion force. Further study is required to determine if these properties translate to an actual improvement in patient outcome.

Economic evaluation of laparoscopic and open inguinal herniorrhaphies: the effect of cost-containment measures and internal hospital policy decisions on costs and charges.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

A mathematical model for preoperative planning of radiofrequency ablation of hepatic tumors.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Comparison of objective outcomes following laparoscopic Nissen fundoplication versus laparoscopic gastric bypass in the morbidly obese with heartburn.

BACKGROUND: Heartburn and gastroesophageal reflux disease (GERD) affects approximately 25-50% of morbidly obese patients. Although objective physiologic testing has been reported extensively in patients following Nissen fundoplication, there are no previous reports of such testing in morbidly obese patients. A life-saving surgical alternative for the morbidly obese patient is gastric bypass surgery, which usually improves heartburn symptoms in addition to many serious health conditions such as diabetes, hypertension, and sleep apnea. We hypothesized that, in morbidly obese patients, gastric bypass surgery would be as effective as Nissen fundoplication in reducing both heartburn symptoms and esophageal acid exposure, as reflected by the DeMeester score. METHODS: Between 1995 and 2000, all patients undergoing laparoscopic Nissen fundoplication (LN) and laparoscopic gastric bypass (LGB) in our practice underwent preoperative and postoperative esophageal physiologic testing. Patients were included in this study that were morbidly obese and had significant heartburn symptoms or objective evidence of acid reflux, and had repeat esophageal physiologic testing after either LN or LGB. Data were obtained through retrospective review of prospectively collected data. RESULTS: Twelve patients met the inclusion criteria: six patients who had LN and six who had LGB. The mean body mass index (BMI) was 55 kg/m2 in the LGB group and 39.8 in the LN group. After surgery, the mean DeMeester score decreased from 64.3 to 2.8 in the LN group ( p = 0.01) and from 34.7 to 5.7 in the LGB group ( p = 0.1). Both groups' mean postoperative DeMeester scores were normal after surgery, and there was no significant difference between the two groups ( p = 0.3). Both groups experienced a significant improvement in heartburn symptoms postoperatively. The mean preoperative symptom score improved from 3.5 to 0.5 in the LN group ( p = 0.01) and from 2.2 to 0.2 in the LGB group ( p = 0.003). There was no difference in the mean postoperative symptom scores between the groups ( p = 0.35). After surgery, mean LES resting pressures increased from 12.9 to 35.5 ( p = 0.003) in the LN group and from 23.6 to 29.7 ( p = 0.45) in the LGB group. There were no complications in either group. CONCLUSION: Results of this study show that laparoscopic gastric bypass and laparoscopic Nissen fundoplication are both effective in treating heartburn symptoms and objective acid reflux in morbidly obese patients. The health benefits of weight loss after laparoscopic gastric bypass should make this operation the procedure of choice in the morbidly obese patient with heartburn.

Laparoscopic antireflux surgery in the elderly.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Outcomes of laparoscopic herniorrhaphy without fixation of mesh to the abdominal wall.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Incidence of cancer of the pancreas, extrahepatic bile duct and ampulla of Vater in the United States, before and after the introduction of laparoscopic cholecystectomy.

BACKGROUND: Some epidemiologic studies have identified cholecystectomy as a risk factor for pancreatic and biliary cancer. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Quality of life before and after laparoscopic Heller myotomy for achalasia.

BACKGROUND: 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). METHODS: 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). RESULTS: 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). CONCLUSIONS: Most aspects of HRQL improve after a laparoscopic Heller myotomy and partial fundoplication for achalasia.

Laparoscopic hepatic artery infusion pump placement.

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.

A decision analysis of the optimal initial approach to achalasia: laparoscopic Heller myotomy with partial fundoplication, thoracoscopic Heller myotomy, pneumatic dilatation, or botulinum toxin injection.

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.

Cost-effective management of common bile duct stones: a decision analysis of the use of endoscopic retrograde cholangiopancreatography (ERCP), intraoperative cholangiography, and laparoscopic bile duct exploration.

BACKGROUND: There are a variety of approaches to the diagnosis and treatment of common bile duct (CBD) stones in patients undergoing laparoscopic cholecystectomy (LC). METHODS: 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. RESULTS: 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%. CONCLUSIONS: 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%).

Preoperative determinants of an esophageal lengthening procedure in laparoscopic antireflux surgery.

BACKGROUND: 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. METHODS: 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). RESULTS: 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). CONCLUSION: 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.