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Biomedical subjects

L W Way

Publications and source records attributed to L W Way.

160 records · Page 9Linked to original sources

The perfused human liver wedge biopsy: a new in vitro model for morphological and functional studies.

We developed a simple and inexpensive method of perfusing small specimens of human liver in vitro that maintains short-term tissue viability as judged by protein transport function and morphological features. The technique allows investigation of liver function at the cellular level in normal specimens and those with hepatobiliary disease. Electron microscopy of specimens perfused with this system demonstrates the presence of an incomplete basement membrane within the space of Disse and shows that human microbodies contain crystalline-like cores morphologically similar to those found in rat liver.

Adult↗

Laparoscopic gastrostomy using T-fasteners as retractors and anchors.

Most feeding or venting gastrostomies can be placed percutaneously via gastroscopy. Laparotomy is required if gastroscopy is not possible--for example, in patients with esophageal strictures or large tumors. We have developed a new technique of laparoscopic gastrostomy, and used it successfully in three patients. The key to this technique is the T-fastener, a nylon suture attached to a metal T-bar, which is introduced via a slotted needle percutaneously and dislodged inside the stomach lumen. Four T-fasteners secure the stomach wall to the anterior abdomen. A balloon catheter gastrostomy tube is then placed over a J-wire through the center of these T-fasteners. This technique requires no gastroscopy or intracorporeal suturing and needs only one port for the laparoscope. It is safe and simple and can be used for patients who require a gastrostomy in whom gastroscopy is not possible or is risky.

Adult↗

Laparoscopic treatment of liver cysts.

Symptomatic simple liver cysts should be treated. In this report we describe the results of a straightforward, well-tolerated laparoscopic operation for this condition. Between 1990 and 1996 we performed 19 laparoscopic liver cyst excisions. The exposed portion of the cyst wall was excised and a piece of omentum was secured into the remaining cyst cavity to prevent recurrence. The average age of the patients was 65 years (range 30 to 81 years). Eight patients (42%) had single simple cysts, nine patients (47%) had multiple simple cysts, and two patients (11%) had polycystic liver disease. Fifty-three percent of the patients had previous abdominal operations, 47% had undergone previous needle aspirations, and one had previously undergone unsuccessful laparoscopic cyst decompression elsewhere. The indications for surgery included abdominal pain, mass, early satiety, malaise, bloating, and shortness of breath. Two patients underwent concurrent cholecystectomies, and one patient underwent concurrent laparoscopic Nissen fundoplication. Follow-up, which averaged 32 months (range 3 to 68 months), is complete in all patients. There was one treatment failure among the patients with simple cysts. Both patients with polycystic liver disease have had recurrent symptoms. The laparoscopic approach to simple liver cysts is relatively straightforward, and if certain technical principles are adhered to, the success rate is very high.

Adult↗

A randomized prospective study of radially expanding trocars in laparoscopic surgery.

Trocar injury is one of the most serious and potentially preventable complications of laparoscopic surgery. Use of a blunt rather than a cutting trocar could be expected to lessen the likelihood of this injury. Therefore complications related to laparoscopic port design were studied by comparing conventional cutting trocars with radially expanding (blunt) trocars. A multicenter, prospective, randomized clinical trial was conducted in 250 adult patients undergoing elective laparoscopic procedures at tertiary care centers and community hospitals. The patients were randomly assigned to one of two groups: group C, conventional cutting trocars; or group S, radially expanding trocars. Sixteen surgeons performed 244 elective laparoscopic procedures; six patients were removed from the study. One hundred nineteen patients were assigned to group S and 125 to group C. The groups were similar with regard to age, sex, and type of procedure. The following data were collected: intraoperative complications related to the trocars, abdominal wall bleeding, visceral or vascular injury, other complications, fascial closure, procedure time, trocar site assessment at 4 and 24 hours postoperatively, and visual analog pain scores at 4, 8, 12, and 24 hours postoperatively. Fascial defects from 10 mm or larger trocars in group C were closed; the fascial defects in group S were not closed. The trocar sites were checked for incisional hernias at late follow-up. Mean operating time was not different between the two groups (group S, 92 +/- 73 minutes; group C, 100 +/- 74 minutes). There were no episodes of intraoperative cannula site bleeding in group S compared with 16 episodes in 13 patients (P < 0.001) in group C. Postoperative wound complications were fewer in group S (13 vs. 23; P < 0.05). Although the pain scores were generally lower in group S, the differences were not significant. Only 3% of the patients in group S had fascial defects of 10 mm or greater that had to be closed. Within a follow-up period of 6 to 18 months, there have been no incisional hernias in either group. This study shows that radially expanding trocars are safe and effective, and less likely than conventional trocars to result in intraoperative or postoperative complications. The defects created by the radially expanding trocars do not have to be routinely closed.

Abdominal Muscles↗

Effect of laparoscopic fundoplication on gastroesophageal reflux disease-induced respiratory symptoms.

Laparoscopic fundoplication controls heartburn and regurgitation, but the effects on the respiratory symptoms of gastroesophageal reflux disease (GERD) are unclear. Confusion stems from difficulty preoperatively in determining whether cough or wheezing is actually caused by reflux when reflux is found on pH monitoring. To date, there is no proven way to pinpoint a cause-and-effect relationship. The goals of this study were to assess the following: (1) the value of pH monitoring in establishing a correlation between respiratory symptoms and reflux; (2) the predictive value of pH monitoring on the results of surgical treatment; and (3) the outcome of laparoscopic fundoplication on GERD-induced respiratory symptoms. Between October 1992 and October 1998, a total of 340 patients underwent laparoscopic fundoplication for GERD. From the clinical findings alone, respiratory symptoms were thought possibly to be caused by GERD in 39 patients (11%). These 39 patients had been symptomatic for an average of 134 months. They were all taking H2-blocking agents (21%) or proton pump inhibitors (79%). Seven patients (18%) were also being treated with bronchodilators, alone (3 patients) or in combination with prednisone (4 patients). Median length of postoperative follow-up was 28 months. In 23 patients (59%) a temporal correlation was found during 24-hour pH monitoring between respiratory symptoms and episodes of reflux. Postoperatively heartburn resolved in 91% of patients, regurgitation in 90% of patients, wheezing in 64% of patients, and cough in 74% of patients. Cough resolved in 19 (83%) of 23 patients in whom a correlation between cough and reflux was found during pH monitoring, but in only 8 (57%) of 14 of patients when this correlation was absent. Cough persisted postoperatively in the two patients who did not cough during the study. These data show that pH monitoring helped to establish a correlation between respiratory symptoms and reflux, and it helped to identify the patients most likely to benefit from antireflux surgery. Following laparoscopic surgery, respiratory symptoms resolved in 83% of patients when a temporal correlation between cough and reflux was found on pH monitoring; heartburn and regurgitation resolved in 90%.

Adult↗

Pigment gallstone pathogenesis: slime production by biliary bacteria is more important than beta-glucuronidase production.

Pigment stones are thought to form as a result of deconjugation of bilirubin by bacterial beta-glucuronidase, which results in precipitation of calcium bilirubinate. Calcium bilirubinate is then aggregated into stones by an anionic glycoprotein. Slime (glycocalyx), an anionic glycoprotein produced by bacteria causing foreign body infections, has been implicated in the formation of the precipitate that blocks biliary stents. We previously showed that bacteria are present within the pigment portions of gallstones and postulated a bacterial role in pigment stone formation through beta-glucuronidase or slime production. Ninety-one biliary bacterial isolates from 61 patients and 12 control stool organisms were tested for their production of beta-glucuronidase and slime. The average slime production was 42 for biliary bacteria and 2.5 for stool bacteria (P <0.001). Overall, 73% of biliary bacteria and 8% of stool bacteria produced slime (optical density >3). In contrast, only 38% of biliary bacteria produced beta-glucuronidase. Eighty-two percent of all patients, 90% of patients with common bile duct (CBD) stones, 100% of patients with primary CBD stones, and 93% of patients with biliary tubes had one or more bacterial species in their stones that produced slime. By comparison, only 47% of all patients, 60% of patients with CBD stones, 62% of patients with primary CBD stones, and 50% of patients with biliary tubes had one or more bacteria that produced beta-glucuronidase. Most biliary bacteria produced slime, and slime production correlated better than beta-glucuronidase production did with stone formation and the presence of biliary tubes or stents. Patients with primary CBD stones and biliary tubes had the highest incidence of slime production. These findings suggest that bacterial slime is important in gallstone formation and the blockage of biliary tubes.

Bacteria↗

Esophageal dysmotility and gastroesophageal reflux disease.

Gastroesophageal reflux disease (GERD) produces a spectrum of symptoms ranging from mild to severe. While the role of the lower esophageal sphincter in the pathogenesis of GERD has been studied extensively, less attention has been paid to esophageal peristalsis, even though peristalsis governs esophageal acid clearance. The aim of this study was to evaluate the following in patients with GERD: (1) the nature of esophageal peristalsis and (2) the relationship between esophageal peristalsis and gastroesophageal reflux, mucosal injury, and symptoms. One thousand six consecutive patients with GERD confirmed by 24-hour pH monitoring were divided into three groups based on the character of esophageal peristalsis as shown by esophageal manometry: (1) normal peristalsis (normal amplitude, duration, and velocity of peristaltic waves); (2) ineffective esophageal motility (IEM; distal esophageal amplitude < 30 mm Hg or >30% simultaneous waves); and (3) nonspecific esophageal motility disorder (NSEMD; motor dysfunction intermediate between the other two groups). Peristalsis was classified as normal in 563 patients (56%), IEM in 216 patients (21%), and NSEMD in 227 patients (23%). Patients with abnormal peristalsis had worse reflux and slower esophageal acid clearance. Heartburn, respiratory symptoms, and mucosal injury were all more severe in patients with IEM. These data show that esophageal peristalsis was severely impaired (IEM) in 21% of patients with GERD, and this group had more severe reflux, slower acid clearance, worse mucosal injury, and more frequent respiratory symptoms. We conclude that esophageal manometry and pH monitoring can be used to stage the severity of GERD, and this, in turn, should help identify those who would benefit most from surgical treatment.

Aged↗

Comparison of laparoscopic total and partial fundoplication for gastroesophageal reflux.

Approximately 25% of patients with gastroesophageal reflux severe enough to be considered for surgical treatment have dysfunction of esophageal peristalsis in addition to dysfunction of the lower esophageal sphincter. A standard total (i.e., Nissen) fundoplication in these patients may be followed by dysphagia, so many experts recommend a partial fundoplication as an alternative. The goal of this study was to compare the clinical results and changes in esophageal function following laparoscopic total and partial fundoplication. Ninety-three patients with gastroesophageal reflux disease had laparoscopic antireflux operations. Total fundoplication was performed in 50 patients with normal esophageal peristalsis. Partial fundoplication was chosen for 43 patients with severe abnormalities of esophageal peristalsis. The same percentage of patients has resolution of heartburn (93%) and regurgitation (97%) after partial as compared to total fundoplication. Dysphagia developed in four patients (8%) after total fundoplication (one patient required dilatation) and in no patients after partial fundoplication. Both operations produced similar changes in lower esophageal sphincter function, but only partial fundoplication was associated with improvement in esophageal dysfunction. Esophageal acid exposure became normal in 92% of patients after total and in 91% of patients after partial fundoplication. Partial fundoplication improves lower esophageal sphincter pressure and esophageal body function and, in patients with abnormal esophageal peristalsis, it corrects reflux without producing dysphagia. Partial and total fundoplication are both indicated in patients with gastroesophageal reflux disease, and the choice of which procedure to use should be based on each patient"s specific esophageal motor function abnormalities.

Deglutition Disorders↗

Importance of preoperative and postoperative pH monitoring in patients with esophageal achalasia.

Gastroesophageal reflux (GER) can develop in patients with esophageal achalasia either before treatment or following pneumatic dilatation or Heller myotomy. In this study we assessed the value of pre- and postoperative pH monitoring in identifying GER in patients with esophageal achalasia. Ambulatory pH monitoring was performed preoperatively in 40 patients with achalasia (18 untreated patients and 22 patients after pneumatic dilatation), 27 (68%) of whom complained of heartburn in addition to dysphagia (group A), and postoperatively in 18 of 51 patients who underwent a thoracoscopic (n=30) or laparoscopic (n=21) Heller myotomy (group B). The DeMeester reflux score was abnormal in 14 patients in group A, 13 of whom had been treated previously by pneumatic dilatation. Two types of pH tracings were seen: (1) GER in eight patients (7 of whom had undergone dilatation) and (2) pseudo-GER in six patients (all 6 of whom had undergone dilatation). Therefore 7 (32%) of 22 patients had abnormal GER after pneumatic dilatation. Postoperatively (group B) seven patients had abnormal GER (6 after thoracoscopic and 1 after laparoscopic myotomy). Six of the seven patients were asymptomatic. These findings show that (1) approximately one third of patients treated by pneumatic dilatation had GER; (2) symptoms were an unreliable index of the presence of abnormal GER, so pH monitoring must be performed in order to make this diagnosis; and (3) the preoperative detection of GER in patients with achalasia is important because it influences the choice of operation.

Adult↗

A hospital's annual rate of esophagectomy influences the operative mortality rate.

The reported operative mortality rate for esophagectomy for malignancy ranges from 2% to 30%. The goal of this retrospective study was to evaluate the relationship between a hospital's annual rate of esophagectomy for esophageal cancer and the clinical outcome of the operation. Discharge abstracts of 1561 patients who had undergone esophagectomy for malignancy at acute care hospitals in California from 1990 through 1994 were obtained from the Office of Statewide Health Planning and Development. The hospitals were grouped according to the number of esophagectomies performed during the 5-year period, and a mortality rate was calculated for each group. Logistic regression analysis was used to determine the relationship between a hospital's rate of esophagectomy and the mortality rate. Esophageal resections were performed in 273 hospitals. An average of two or fewer resections were performed annually in 88% of hospitals, which accounted for 50% of all patients treated. The mortality rate in hospitals with more than 30 esophagectomies for the 5-year period was 4.8%, compared with 16% for hospitals with fewer than 30 esophagectomies. This could not be accounted for by other health variables affecting the patients' risk for surgery. There was a striking correlation between a hospital's frequency of esophagectomy and the outcome of this operation. The results support the proposition that high-risk general surgical procedures, such as esophagectomy for malignancy, should be restricted to hospitals that can exceed a yearly minimum experience.

Adult↗

Comparison of thoracoscopic and laparoscopic Heller myotomy for achalasia.

For more than three decades experts have debated the relative merits of thoracoscopic Heller myotomy (no antireflux procedure) vs. laparoscopic Heller myotomy plus Dor fundoplication for treatment of achalasia. The aim of this study was to compare the results of these two methods with respect to (1) relief of dysphagia, (2) incidence of postoperative gastroesophageal reflux, and (3) hospital course. Sixty patients with esophageal achalasia were operated on between 1991 and 1996. Thirty underwent a thoracoscopic Heller myotomy and 30 had a laparoscopic Heller myotomy with a Dor fundoplication. The two groups were similar with respect to demographic characteristics, clinical findings, and extent of manometric abnormalities. Preoperative pH monitoring showed abnormal reflux in two patients in the laparoscopic group. Average hospital stay was 84 hours for the thoracoscopic group and 42 hours for the laparoscopic group. Excellent (no dysphagia) or good (dysphagia less than once a week) results were obtained in 87% of patients in the thoracoscopic group and in 90% of patients in the laparoscopic group. Postoperative pH monitoring showed abnormal reflux in 6 (60%) of 10 patients in the thoracoscopic group and in 1 (10%) of 10 patients in the laparoscopic group. The two patients in the laparoscopic group who had reflux preoperatively had normal reflux scores postoperatively. Laparoscopic Heller myotomy with Dor fundoplication was found to be superior to thoracoscopic Heller myotomy. Both operations relieved dysphagia, but the laparoscopic approach avoided postoperative reflux and even corrected reflux present preoperatively. In addition, the patients were more comfortable and left the hospital earlier following a laparoscopic myotomy. Whether it is truly possible to perform a Heller myotomy without an antireflux procedure in a way that relieves dysphagia and regularly avoids reflux remains questionable.

Adult↗

Barrett's esophagus: a surgical disease.

Barrett's metaplasia can develop in patients with gastroesophageal reflux disease (GERD), and metaplasia can evolve into dysplasia and adenocarcinoma. The optimal treatment for Barrett's metaplasia and dysplasia is still being debated. The study reported herein was designed to assess the following: (1) the incidence of Barrett's metaplasia among patients with GERD; (2) the ability of laparoscopic fundoplication to control symptoms in patients with Barrett's metaplasia; (3) the results of esophagectomy in patients with high-grade dysplasia; and (4) the character of endoscopic follow-up programs of patients with Barrett's disease being managed by physicians throughout a large geographic region (northern California). Five-hundred thirty-five patients evaluated between October 1989 and February 1997 at the University of California San Francisco Swallowing Center had a diagnosis of GERD established by upper gastrointestinal series, endoscopy, manometry, and pH monitoring. Thirty-eight symptomatic patients with GERD and Barrett's metaplasia underwent laparoscopic fundoplication. Eleven other consecutive patients with high-grade dysplasia underwent transhiatal esophagectomies. Barrett's metaplasia was present in 72 (13%) of the 535 patients with GERD. The following results were achieved in patients who underwent laparoscopic fundoplication (n = 38): Heartburn resolved in 95% of patients, regurgitation in 93% of patients, and cough in 100% of patients. With regard to transhiatal esophagectomy (n = 11), the average duration of the operation was 339 +/- 89 minutes. The only significant complications were two esophageal anastomotic leaks, both of which resolved without sequelae. Mean hospital stay was 14 +/- 5 days. There were no deaths. The specimens showed high-grade dysplasia in seven patients and invasive adenocarcinoma (undiagnosed preoperatively) in four (36%). These results can be summarized as follows: (1) Barrett's metaplasia was present in 13% of patients with GERD being evaluated at a busy diagnostic center; (2) laparoscopic fundoplication was highly successful in controlling symptoms of GERD in patients with Barrett's metaplasia; (3) in patients with high-grade dysplasia esophagectomy was performed safely (invasive cancer had eluded preoperative endoscopic biopsies in one third of these patients); and (4) even though periodic endoscopic examination of Barrett's disease is universally recommended, this was actually done in fewer than two thirds of patients being managed by a large number of independent physicians in this geographic area.

Adenocarcinoma↗