bluuebunny/crossref_metadata_2025 huggingface dataset:
Surgeon's Approach to the Thyroid Gland: Surgical Anatomy and the Importance of Technique
Authors: Bliss Richard D. , Gauger Paul G. , Delbridge Leigh W.
Published: August 2002

The cornerstone of safe and effective thyroid surgery is thorough training in and understanding of thyroid anatomy and pathology. With appropriate techniques, total thyroid lobectomy and total thyroidectomy (which should be considered simply as a bilateral total thyroid lobectomy performed during the same operation) can be undertaken with minimal risk of damage to the recurrent laryngeal nerves, the external branches of the superior laryngeal nerves, and the parathyroid glands. Safe surgery requires a specific operative plan, progressing in a series of logical, orderly, anatomically based steps. Exposure of the thyroid gland is followed by careful dissection of the superior pole, utilizing the avascular plane between the superior pole and the cricothyroid muscle to identify and preserve the external branch of the superior laryngeal nerve. Medial retraction of the gland then allows dissection of the lateral aspect of the thyroid lobe. Protection of the recurrent laryngeal nerves and preservation of the blood supply to the parathyroid glands is best achieved by “capsular dissection,” ligating the tertiary branches of the inferior thyroid artery on the gland surface. If a parathyroid gland cannot be preserved or becomes ischemic after dissection of its vascular pedicle, it should be immediately minced and autotransplanted into the ipsilateral sternocleidomastoid muscle. The current evolution of outpatient or short‐stay thyroidectomy emphasizes the need to avoid complications by utilizing meticulous surgical technique. Minimally invasive thyroidectomy utilizing endoscopic techniques may also affect the practice of thyroid surgery. Even so, understanding the surgical anatomy of the thyroid gland and its possible variations is paramount to safe and effective surgery.
Total Thyroidectomy or Thyroid Lobectomy in Patients with Low‐risk Differentiated Thyroid Cancer: Surgical Decision Analysis of a Controversy Using a Mathematical Model
Authors: Kebebew Electron , Duh Quan‐Yang , Clark Orlo H.
Published: August 2002

There is a general consensus that total or near‐total thyroidectomy is the optimal treatment for patients with high risk differentiated thyroid cancer (DTC), but the optimal extent of thyroidectomy in patients with low risk DTC continues to be controversial. To determine the optimal extent of thyroidectomy in patients with low risk DTC, we used decision analysis to compare the trade‐offs of total thyroidectomy (TT) to thyroid lobectomy (TL). The decision analysis model included the probabilities of thyroidectomy complications, risk of DTC recurrence, and death from DTC. This information was obtained from the literature and from outcome data for patients with low risk DTC from our institution. In addition, the concept of utilities was used in the analysis. To determine the utility of each health outcome state (thyroidectomy complication, DTC recurrence, and DTC mortality for low risk patients) a survey was conducted. Overall, prospective patients viewed DTC recurrence as less desirable than thyroidectomy complication. The utilities assigned by the survey participants varied over a wide range, with 61.5% of the individuals viewing the occurrence of a thyroidectomy complication as better than DTC recurrence. At baseline utilities and probabilities, TT had a higher expected utility than TL. One‐way sensitivity analysis varying the rates of (1) thyroidectomy complication, (2) DTC recurrence, and (3) DTC mortality over the possible range showed that complication from initial thyroidectomy was the most important factor that determined the preferred extent of thyroidectomy. TL was the preferred surgical approach only if a complication rate of > 33:1, TT/TL complication rate ratio, was assumed. When no differences in DTC recurrence between the two approaches was assumed in the model, TL had a higher expected utility using the baseline utilities of thyroidectomy complication and DTC mortality. The analysis indicates that TT in patients with low risk DTC is preferable to TL. However, TL is preferred if (1) no difference in the DTC recurrence rate between the two approaches is assumed, (2) a higher complication rate for TT is used (> 33 times higher), or (3) the utility ratio of thyroidectomy complication to DTC recurrence is < 0.8 TL. We believe this decision analysis model provides an objective approach that others can use to select the optimal extent of thyroidectomy based on patient preference of health outcome states, institution‐specific outcome data for DTC recurrence or mortality, and the surgeon‐specific complication rate.
Modern Anesthetic Techniques for Thoracic Operations
Authors: Brodsky Jay B. , Fitzmaurice Brett
Published: August 2002

Continuing advances in anesthesiology enable surgeons to perform more and more complex operations. Nowhere is this relation more important than for the patient undergoing thoracic surgery. Specialized anesthetic techniques including safe lung separation, the maintenance of oxygenation during selective one‐lung ventilation, and effective postoperative analgesia allow procedures such as lung volume reduction surgery and lung transplantation to be performed routinely. This paper reviews modern clinical practices in the field of thoracic anesthesia.
Vagus
Authors: Gunn S.W.A.
Published: August 2002

World Journal of Surgery

has been studying the etymologic genealogy of some common terms in surgical usage. Thus the bile duct strangely leads us to symphony orchestras, dukes, coins, and dictators; and a bacteriologic culture is found to be related to such unexpected cousins as religion, agronomy, war, and civilization. If these connections appear somewhat vague, they could not be more so than with the vagus.—The Editor
Gut Ischemia, Oxidative Stress, and Bacterial Translocation in Elevated Abdominal Pressure in Rats
Authors: Eleftheriadis E. , Kotzampassi K. , Papanotas K. , Heliadis N. , Sarris K.
Published: August 2002

The purpose of this experimental study was to investigate whether the increased intraabdominal pressure due to gas insufflation creates intestinal ischemia leading to oxygen free radical production and bacterial translocation. A group of 88 rats were studied, 40 of which were subjected to a 15 mmHg pressure pneumoperitoneum for 60 minutes, with the following parameters being studied: mean arterial pressure after carotid catheterization; intestinal microcirculation by means of the laser‐Doppler technique; gut metabolic activity (O2 extraction) by blood sampling from portal vein and carotid artery; intestinal, hepatic, splenic, and lung free radical production (malondialdehyde); and bacterial translocation toward the mesenteric lymph nodes, liver, and spleen at 3 and 18 hours after pneumoperitoneum deflation. The mean arterial pressure exhibited no alterations, whereas the jejunal mucosa microcirculation was significantly decreased (p= 0.0001), as was the gut metabolic activity (p= 0.025). Malondialdehyde was increased in gut mucosa (p= 0.0002), liver (p= 0.02), spleen (p= 0.03), and lung (p= 0.017). Bacterial translocation toward the mesenteric lymph nodes (p= 0.002), spleen (p= 0.002), and liver (p= 0.05) was increased in the 3‐hour group; in the 18‐hour group bacteria were not found in mesenteric lymph nodes but were in liver (p= 0.008) and spleen (p= 0.035). It is concluded that elevated intraabdominal pressure in the rat leads to intestinal ischemia, oxygen free radical production, and bacterial translocation. These results must be reproduced in humans and their clinical significance clarified.
Treatment of Liver Metastases of Carcinoid Tumors
Authors: Ahlman Håkan , Westberg Gunnel , Wängberg Bo , Nilsson Ola , Tylén Ulf , Scherstén Tore , Tisell Lars‐Erik
Published: August 2002

Liver metastases imply a major problem in patients with carcinoid tumors. Patients with localized disease should always undergo resection for cure. Patients with distant metastatic disease can also undergo resection for potential cure or symptom palliation because of the slow growth rate of many carcinoid tumors. In patients with the midgut carcinoid syndrome and bilobar hepatic disease we have performed primary surgery to relieve such symptoms as intestinal obstruction and ischemia, followed by successive embolizations of the hepatic arteries to reduce functional tumor burden in the liver. For optimal palliation, all patients with residual tumor were treated by octreotide. In a consecutive series of 64 patients with the midgut carcinoid syndrome we thus attained a 5‐year survival rate of 70%. Fourteen of the patients underwent intentionally curative surgery (e.g., primary surgery followed by liver surgery). Of these patients, none died from their tumor disease during the period of study. The value of adjunctive interferon therapy is currently under evaluation.
Options for Treatment of Persistent Aneurysm Perfusion after Endovascular Repair
Authors: Ivancev K. , Chuter T. , Lindh M. , Lindbladt B. , Brunkwall J. , Risberg B.
Published: August 2002

Persistent aneurysm perfusion represents failure of endovascular repair. The leak may occur around either end of the prosthesis or through a collateral route. Most cases can be treated by endovascular means. Stents can be rotated, the prosthesis can be lengthened at either end, and collateral pathways can be occluded, all without recourse to open repair. This report describes the management of persistent aneurysm perfusion in five patients from a total experience of 32 cases of endovascular aneurysm repair.
Posterior Retroperitoneoscopy as a New Minimally Invasive Approach for Adrenalectomy: Results of 30 Adrenalectomies in 27 Patients
Authors: Walz Martin K. , Peitgen Klaus , Hoermann Rudolf , Giebler Reiner M. , Mann Klaus , Eigler Friedrich W.
Published: August 2002

Posterior retroperitoneoscopic adrenalectomy is a new minimally invasive method. It represents an alternative to conventional open procedures and laparoscopic techniques. Between July 1994 and November 1995 a total of 30 retroperitoneoscopic adrenalectomies were performed on 27 patients. In 24 patients, unilateral tumors were seen (size 1–7 cm): seven Cushing adenomas, five Conn adenomas, seven pheochromocytomas, four hormonally inactive tumors, one cyst. Three patients suffered from Cushing syndrome with bilateral adrenal gland hyperplasias (two inoperable pituitary gland tumors, one bronchial carcinoid with ACTH secretion). The operations were carried out in prone position. After balloon dilatation of the retroperitoneum and creation of a pneumoperitoneum the preparation of the adrenal gland was performed via three trocar sites positioned below the 12th rib. Twenty‐five adrenalectomies were completed endoscopically, and five times (among four patients) conversion to the conventional posterior technique was necessary. The average operating time of complete endoscopic adrenalectomies was 124 minutes (45–225 minutes); blood loss was 10 to 120 ml. With minimal need for postoperative analgesia (average dosage 7.9 mg of piritramide), mobilization and adequate food uptake were possible on the day of operation. The posterior retroperitoneoscopic adrenalectomy is a relatively fast, safe method, with the advantages of the posterior open approach and minimally invasive surgery. It therefore represents an important addition to adrenal gland surgery.
Tall‐Cell Variant of Papillary Thyroid Cancer: Disregarded Entity?
Authors: Rüter A. , Nishiyama R. , Lennquist S.
Published: August 2002

The tall‐cell variant of papillary thyroid carcinoma (TCV) has been described as an aggressive tumor with a significantly higher incidence of recurrence and mortality than other forms of papillary carcinoma. In some series it has accounted for up to 10%, whereas in other series it has not been reported at all, indicating that there are difficulties identifying it. In a series of 162 consecutively treated patients with papillary thyroid carcinoma treated by total thyroidectomy according to a highly standardized procedure, all specimens were specifically examined by an international group of pathologists to establish the occurrence of TCV. All patients with TCV were studied with regard to local aggressiveness, the presence of metastases, iodine uptake, DNA pattern, thyroglobulin production, treatment (surgical and adjuvant), and outcome (follow‐up 3–17 years, median 10 years). At primary histopathologic evaluation by the local pathologist, three patients were recorded as having TCV. At special evaluation by the expert group, eight more cases were found, giving a total of 11 patients in this series (7%). Five of them had extracapsular growth, and four were multifocal. Three had metastases at the time of admission. Seven tumors were diploid, one tetraploid, and three aneuploid. Of the three patients with primary distant metastases two died (8 and 24 months after operation), and one is still alive after 10 years. Four other patients developed recurrences, one of whom died from cardiac failure, but the others have so far been treated successfully. Two of these recurrences had no radioiodine uptake, and one had no rise in thyroglobulin concentrations; the other two had rising values that correlated with recurrence. The other four patients are alive without recurrence. It was concluded that identification of the TCV requires examination by an experienced pathologist. Moreover, it may have a higher incidence than is generally recognized. No reliable criteria for prognostic classification were identified. The results suggest that early identification and active treatment can lead to an outcome more favorable than has previously been described.
Interventional and surgical treatment of pancreatic abscess
Authors: Mithöfer Kai , Mueller Peter R. , Warshaw Andrew L.
Published: August 2002

Pancreatic abscess is one of the infectious complications of acute pancreatitis. It is a collection principally containing pus, but it may also contain variable amounts of semisolid necrotic debris. Most of these abscesses evolve from the progressive liquefaction of necrotic pancreatic and peripancreatic tissues, but some arise from infection of peripancreatic fluid or collections elsewhere in the peritoneal cavity. Included also are abscesses found after surgical débridement and drainage of pancreatic necrosis. Although open surgical treatment of infected necrosis is the established treatment of choice, percutaneous drainage of abscesses is successful in some circumstances. We used percutaneous catheter drainage in 39 patients during 1987–1995. Only 9 of 29 (31%) attempts at primary therapy were successful; 2 patients died, and 18 required subsequent surgical drainage. On the other hand, 14 of 14 patients with recurrent or residual abscesses after surgical drainage were successfully drained percutaneously. Percutaneous catheter drainage of pancreatic abscesses may be useful for initial stabilization of septic patients, drainage of further abscesses after surgical intervention (especially when access for reoperation will be difficult), associated abscesses remote from the pancreas, and selected unilocular collections at a sufficient interval after necrotizing pancreatitis to have allowed essentially complete liquefaction.
Hepatic Surgery and Hepatic Surgical Anatomy: Historical Partners in Progress
Authors: McClusky David A. , Skandalakis Lee J. , Colborn Gene L. , Skandalakis John E.
Published: August 2002

Whether for hepatic trauma or transplantation, a surgeon's knowledge of hepatic anatomy commonly determines a patient's outcome. The first medically relevant anatomic studies of the liver emerged with the endeavors of Herophilus and Erasistratus between 310 and 280 bc. Yet it was not until after the development of anesthesia and antisepsis that the first formal resections were performed during the late 1800s. After vascular occlusion principles had been developed as a means of successful hemorrhage control, several deliberate attempts were made to repair the liver surgically. Such efforts culminated in the work of Wendel in 1910 when he followed avascular planes during hepatectomy. The functional anatomy of surgery and surgical technique had suddenly joined in an effort to advance the practice, and eventually the efficacy of hepatic surgeons in facilitating the modern era of segmental anatomy extended hepatectomies and transplantation surgery.
Restorative Proctocolectomy or Rectum‐Preserving Surgery in Patients with Familial Adenomatous Polyposis: Results of a Prospective Study
Authors: Tonelli Francesco , Valanzano Rosa , Monaci Iacopo , Mazzoni Paolo , Anastasi Alessandro , Ficari Ferdinando
Published: August 2002

Surgical treatment of familial adenomatous polyposis (FAP) is still controversial. From 1984 we carried out a prospective evaluation of total colectomy with ileorectal anastomosis (IRA) and restorative proctocolectomy with ileal pouch–anal anastomosis (IPAA) to determine differences in postoperative complications, functional results, occurrence of desmoids, and recurrence of polyps in the rectal stump. IRA was performed below the peritoneal reflection and was indicated in the absence of rectal cancer and in the presence of fewer than 10 polyps or minute polyposis in the last 10 cm of the rectal mucosa. IRA patients underwent a regular endoscopic follow‐up and prolonged sulindac administration (100 mg twice daily). When criteria for IRA were absent, IPAA was performed adopting a manual anastomosis at the pectinate line. Fourteen patients were operated with IRA and 24 with IPAA. There was no difference in sex and age between the two groups of patients. The number of rectal polyps was significantly different in the two groups. Immediate postoperative complications were observed in only five IPAA patients, three of whom (12%) required reoperation. Late postoperative complications occurred more frequently in IRA patients (14%) than in IPAA patients (4%). Desmoids developed in both groups (five in the IRA group and four in IPAA group). The number of bowel movements was similar in both groups, but 25% of IPAA patients complained of nocturnal fecal soiling. Fulguration or polypectomy for recurrent polyps was necessary in all but two IRA patients at follow‐up. The rectal stump was easily eradicated by polyps in all but four patients with minute polyps at surgery. In the latter patients a diffuse or carpeting rectal polyposis occurred. IPAA can give optimum control of colorectal polyposis in FAP patients with an acceptable incidence of postoperative complications and satisfactory functional results. This type of surgical procedure is indicated in most FAP patients, and IRA should be reserved for patients without polyps or with fewer than 10 polyps in the rectal stump; otherwise growth of polyps cannot be adequately controlled.
Ultra‐low Anterior Resection and Coloanal Pouch Reconstruction for Carcinoma of the Distal Rectum
Authors: Guillem Jose G.
Published: August 2002

Facilitated by an enhanced appreciation for pelvic anatomy and physiology along with a better understanding of patterns of rectal cancer spread, great advances have been made in our ability to perform restorative resections for an ever‐increasing proportion of mid and distal rectal cancers. Whereas oncologic results following a low anterior resection were the principal concern 20 years ago, recent efforts have focused on improving functional results as well. Aspirations for improved function need to be tempered by the realization that improved sphincter‐saving rates must follow improved oncologic results rather than jeopardize them. Some crucial questions are addressed in this paper: What are the variables involved in optimizing the oncologic and functional results of a low anterior resection and a coloanal reconstruction? What are the issues involved in selecting a particular coloanal reconstruction (straight versus pouch, stapled versus handsewn, with or without fecal diversion) for a particular patient? Who is not a good candidate for a coloanal reconstruction?
Determinants of Survival following Hepatic Resection for Metastatic Colorectal Cancer
Authors: Bakalakos Efthimios A. , Kim Julian A. , Young Donn C. , Martin Edward W.
Published: August 2002

Hepatic resection remains the only potentially curative treatment for metastatic colorectal cancer. This retrospective review study was undertaken in an attempt to identify factors that influence patient survival following hepatic resection for metastatic colorectal cancer. From January 1978 to December 1993, a total of 301 patients underwent a total of 345 planned hepatic resections for metastatic colorectal cancer. Of those, 245 patients had one resection, 44 had two resections, and 12 had three resections. For all patients the overall median survival was 20.6 months, operative mortality was 1.1%, and overall morbidity was 17.2%. Average hospital stay was 9 days. Statistical analysis included univariate analysis using log rank comparisons, Kaplan‐Meier survival curves, and multivariate analysis using Cox proportional hazards regression. The statistically significant factors that influenced survival were distribution of liver metastases, unilobar versus bilobar (p= 0.0001), resected versus nonresected (p < 0.0001), and tumor‐free surgical margins versus positive margins (p= 0.001). Surprisingly, the disease‐free interval and the original stage of the primary tumor did not predict survival (p= not significant). Other factors that had no influence on survival were type of resection, size and number of liver metastases, ABO blood group, and the number of perioperative blood transfusions. For those patients who underwent resection of unilobar metastases with tumor‐free margins, the 5‐year survival rate was 29% with a median survival of 35 months and eight survivors > 7 years. In addition, one patient with bilobar disease had survival > 7 years and five patients who had resection of hepatic metastases and extrahepatic cancer simultaneously had survival > 3 years. Our data support the concept that patients with unilobar metastatic disease who undergo surgical resection with tumor‐free surgical margins can be afforded a significant opportunity at long‐term survival with acceptable morbidity, mortality, and hospital stay. Also, certain patients with bilobar or extrahepatic disease (or both) who undergo complete resection can enjoy a long‐term survival. In these subgroups of patients resection should be considered on an individual basis.
Staged Physiologic Restoration and Damage Control Surgery
Authors: Moore Ernest E. , Burch Jon M. , Franciose Reginald J. , Offner Patrick J. , Biffl Walter L.
Published: August 2002

The fundamental objective of staged laparotomy is to accomplish definitive operative management in a calculated, stepwise fashion based on the patient's physiologic tolerance. This important concept has emerged from collective experience with massive acute abdominal injuries but clearly extends to elective operative procedures and surgical challenges in other torso compartments. Whereas the inability to achieve hemostasis is due most frequently to a recalcitrant coagulopathy following trauma, other scenarios include inaccessible venous injuries, coexisting extraperitoneal life‐threatening injuries, uncertain viability of abdominal contents, and the inability to reapproximate abdominal fascia due to reperfusion‐induced visceral edema. There are five critical decision‐making phases of staged laparotomy: I, patient selection; II, intraoperative reassessment; III, physiologic restoration in the surgical intensive care unit; IV, return to the operating room for definitive procedures; and V, abdominal wall reconstruction. The abdominal compartment syndrome (ACS) is a common, often insidious complication of staged laparotomy. In fact, during phases II and III there is often a delicate balance between effective pressure tamponade of capillary bleeding and the untoward effects of the ACS. During phases IV and V a frequent dilemma is how to enclose the abdominal contents to reduce protein loss and facilitate patient mobilization.
Thoracoscopic Surgery for Spontaneous Pneumothorax
Authors: Liu Hui‐Ping , Yim Anthony P.C. , Izzat M. Bashar , Lin Pyng Jing , Chang Chau‐Hsiung
Published: August 2002

Spontaneous pneumothorax in apparently healthy individuals is a relatively common occurrence. The management of patients with spontaneous pneumothorax remains controversial. With the advances in thoracoscopic techniques and instrumentation, video‐assisted thoracic surgery (VATS) is now accepted by many as the procedure of choice for surgical treatment of spontaneous pneumothorax. We report our combined experience with 757 patients who suffered from recurrent or persistent spontaneous pneumothorax treated by VATS over a 5‐year period. Surgical indications included persistent air leak (n= 165), recurrence (n= 325), radiologically demonstrated huge bulla (n= 12), spontaneous hemopneumothorax (n= 13), incomplete expansion of the lung (n= 212), and bilateral involvement (n= 30). Several surgical procedures were undertaken, based on the thoracoscopic findings: endoscopic stapled bullectomy (n= 312), argon beam coagulation (n= 6), endoscopic suturing (n= 52), and endoloop ligation (n= 352). In 49 cases, mechanical or chemical pleurodesis was the only procedure performed. There were no mortalities or intraoperative hazards. Complications consisted of wound infections (n= 16), localized empyema (n= 2), chest wall bleeding (n= 1), and persistent air leaks (bulla type III) (n= 31). The median duration of the operation was 55 minutes (15–160 minutes), and the average postoperative hospital stay was 4.5 days (range 0–27 days). There were 16 recurrences (2.1%), after a mean follow‐up of 30 months (range 1–60 months). Seven patients had recurrence from 9 to 17 months after stapled bullectomy. All the remaining patients had recurrence after failed pleurodesis. On the basis of our results, we conclude that video‐assisted thoracoscopic management allows effective, safe performance of standard surgical procedures, avoiding a formal thoracotomy incision. We consider thoracoscopy the treatment of choice for patients with pneumothorax requiring surgical therapy.
Transabdominal Extensive Esophagogastric Devascularization with Gastroesophageal Stapling for Management of Noncirrhotic Portal Hypertension: Long‐term Results
Authors: Mathur Surendra K. , Shah Sudeep R. , Nagral Sanjay S. , Soonawala Zahir F.
Published: August 2002

Outside Japan portosystemic shunts have been favored as the surgical procedure of choice for the management of portal hypertension of noncirrhotic etiology. Devascularization procedures have resulted in high rebleed rates probably owing to a limited extent of devascularization. We performed this study to assess the efficacy of our modification of Sugiura's procedure for long‐term control of variceal bleeding in patients with noncirrhotic portal hypertension. Forty‐six patients with extrahepatic portal venous obstruction (EHPVO) and 22 with noncirrhotic portal fibrosis (NCPF) were subjected to transabdominal extensive esophagogastric devascularization with esophageal or gastric stapled transection (modified Sugiura's procedure), 38 in an emergency situation and 30 electively. Follow‐up endoscopies were performed every 6 months. Operative mortality, morbidity, variceal status, and causes of recurrent bleeding were evaluated. The postoperative mortality was 4%. Early procedure‐related complications were seen in 6%, and esophageal strictures formed in 7 of 45 survivors undergoing esophageal transection (15%). Over a mean ± SD follow‐up of 53 ± 34 months, 95% of patients were free of varices. Seven survivors (11%) had a rebleed, but only 5% were due to varices (two esophageal, one gastric). Six (9%) patients developed gastropathy. The 5‐year survival was 88%. The modified Sugiura's procedure is safe and effective for long‐term control of variceal bleeding especially in the emergency setting and in patients with anatomy unsuitable for shunt surgery or if surgical expertise for a shunt operation is not available.
Principles of Economic Evaluation in Surgery
Authors: Krahn Murray
Published: August 2002

This document reviews the key principles of economic evaluation as they pertain to the evaluation of surgical questions. It addresses the role of economic evaluation in health care decision making, describes the central issues in performing or evaluating an economic evaluation, and finally offers several examples of recent economic evaluations from the surgical literature. A concise annotated reference section is provided for those wishing to read further.
Relaparotomy in Peritonitis: Prognosis and Treatment of Patients with Persisting Intraabdominal Infection
Authors: Koperna Thomas , Schulz Franz
Published: August 2002

Some patients are prone to persisting intraabdominal infection regardless of initial eradication of the source of infection. Our aim was to characterize patients who had to undergo relaparotomy for persisting abdominal sepsis using simple clinical parameters and to define those patients who are susceptible to benefit of aggressive surgical treatment by early and repeated reoperations to control multiple organ dysfunction syndrome (MODS) caused by ongoing intraabdominal infection. Persisting abdominal sepsis was the cause of death in all of our patients who had to undergo relaparotomy. Controlling persisting abdominal sepsis should achieve a reduction in the tremendously high mortality rate. Performing a case‐control study, we retrospectively reviewed 523 consecutive patients with secondary peritonitis treated from 1986 to 1996 and focused our attention on 105 patients, in whom standard surgical treatment of secondary peritonitis failed and who had to undergo relaparotomy for persisting abdominal sepsis (study group). Overall, there was no significant difference in the postoperative mortality rate between “planned relaparotomy” and “relaparotomy on demand” (54.5% versus 50.6%). Equally clear risk estimations were given preoperatively by both the Acute Physiology and Chronic Health Evaluation (APACHE) II and the Goris scores. There was a significant difference between patients of the control group and patients of the study group with regard to preoperative APACHE II score, Goris score, age >70 years, albumin <30 g/L, extent of peritonitis, and outcome (p= 0.0001). Reexploration performed more than 48 hr after the initial operation resulted in a significantly higher mortality rate (76.5% versus 28%; p= 0.0001). However, the time of reoperation had no significant impact on survival in patients with an APACHE II score of ≥26, because physiologic derangement is such that only a few patients could benefit from reoperation. The lowest mortality rate (9%) was achieved in patients who underwent reoperation on demand within 48 hr. We conclude that patients >70 years of age with secondary peritonitis extending over the entire abdomen and a greater degree of physiologic compromise (serum albumin levels <30 g/L, preoperative APACHE II scores >20, and existing organ failure measured by the Goris score) are at high risk for developing persistent intraabdominal infection. Our data show that timely relaparotomy provides the only surgical option that significantly improves outcome. However, aggressive surgical treatment has reached its limit in patients whose source of infection could not be controlled at the initial operation. To improve overall survival the decision to perform a relaparotomy on demand after an initially successful eradication of the source of infection must be made within 48 hr, at least before MODS emerges.
Five‐year Prospective Audit of Routine Intravenous Cholangiography and Selective Endoscopic Retrograde Cholangiography with or without Intraoperative Cholangiography in Patients Undergoing Laparoscopic Cholecystectomy
Authors: Pietra Nicola , Sarli Leopoldo , Maccarini Pierangelo Ugo , Sabadini Guido , Costi Renato , Gobbi Sara
Published: August 2002

Consensus has never been reached regarding the need or the imaging technique for evaluating the common bile duct (CBD) in patients considered for cholecystectomy. With the advent of laparoscopic cholecystectomy there has been a resurgence of interest in the role of preoperative intravenous cholangiography (IVC) as an alternative for evaluating the CBD. The purpose of this audit was to assess whether a diagnostic workup based on IVC, which permits selective use of intraoperative cholangiography (IOC) and endoscopic treatment of CBD stones before surgery, could be useful in patients undergoing laparoscopic cholecystectomy (LC). In patients without jaundice, gallstone pancreatitis, a prior diagnosis of CBD stones, a prior history of contrast allergy, or a risk of contrast‐associated acute renal failure, IVC was performed routinely. Patients suspected to have CBD stones based on IVC results or with inconclusive IVC and patients with a strong clinical suspicion of CBD stones were referred for endoscopic retrograde cholangiography (ERC). IOC was carried out in patients who had a history of contrast allergy or risk of contrast‐associated acute renal failure and whenever the surgeon was in doubt as to the biliary anatomy or CBD clearance. IVC was carried out in 1155 patients, ERC in 225, and IOC in 54. IVC was conclusive in 1132 patients, with a diagnostic accuracy of 99%. Our workup permitted the sequential endoscopic‐laparoscopic treatment of cholecystocholedocholithiasis in 162 cases. During the follow‐up period residual CBD stones were detected in four patients. Our diagnostic workup showed that routine IVC exposes the population to a large radiation burden, and the cost is high for the small number of patients who benefit. Moreover, it does not seem helpful in reducing the incidence of CBD injuries during LC.
Hepatic Vein Reconstruction by External Iliac Vein Graft Using Vascular Clips
Authors: Kaneoka Yuji , Yamaguchi Akihiro , Isogai Masatoshi , Hori Akihiro
Published: August 2002

The utility of hepatic vein reconstruction following resection of segments VII and VIII plus the right hepatic vein (RHV) is still controversial. The purpose of this study was to investigate the surgical benefits of hepatic vein reconstruction using stapled vascular clips and the draining area of hepatic vein using angiographic computed tomography (CT) to determine strict indications for hepatic vein reconstruction. Five patients underwent RHV reconstruction by external iliac vein graft using stapled vascular clips (VCS clips) following resection of segments VII and VIII, regardless of whether an inferior right hepatic vein (IRHV) was present. In eight other patients CT during arterial portography (CTAP) under temporary RHV occlusion using a balloon catheter was performed to determine the drainage area of the RHV. Operating times were 240 to 400 minutes (mean 336 ± 59 minutes), and the mean hepatic vein reconstruction time was 26 ± 5 minutes. There were no complications related to the surgery. Follow‐up examinations showed patency of the graft in all cases; three patients are still alive with long‐term graft patency of 10 to 24 months. CTAP under RHV occlusion demonstrated that segment VI and part of segment V were almost hypoattenuated in cases of absent or small IRHV, although those segments were hyperattenuated in thick IRHV and RHV‐IRHV communicating patients. In conclusion, this anastomotic technique using vascular clips resulted in sound patency of the graft, which was accomplished by a simple technique. Preoperative CTAP with the RHV occlusion method can be useful for determining whether hepatic vein reconstruction is necessary.
External Fixation of the Lumbar Spine in a Canine Model
Authors: Walker Tamara M. , Pierce William A. , Welch Robert D.
Published: August 2002

Objective— To compare the mechanical properties of two types of external skeletal fixation of the lumbar spine with polymethylmethacrylate (PMMA)/Steinmann pin fixation in a canine unstable spine model.

Study design— Cadaver study.

Sample population— Lumbar spines of 17 mature large‐breed dogs.

Methods— Spine stiffness (N‐m/deg) in flexion, extension, and rotation under physiological loading conditions and spine strength (N‐m) in flexion were determined. Spines were destabilized at L3‐L4, instrumented and retested. Fixation techniques included four‐pin PMMA (PMMA4), eight‐pin PMMA (PMMA8), eight‐pin biplanar type I external skeletal fixator (ESF) (SK), and eight‐pin spinal arch ESF (ARCHES).

Results— All fixation groups were as stiff as intact spines in extension and rotation and were significantly stiffer in flexion. In flexion, both PMMA8 and ARCHES were significantly stiffer than SK, and PMMA8 was significantly stiffer than PMMA4. In rotation, PMMA8 and ARCHES were significantly stiffer than SK, and in flexion to failure, PMMA8 and ARCHES were significantly stiffer than PMMA4.

Conclusions— External skeletal spinal fixation (ESSF) has mechanical properties comparable to more commonly used PMMA/pin internal fixation techniques.

Clinical relevance— External fixation of the canine spine has several potential advantages over internal fixation including minimal dissection for pin placement, the ability to span affected vertebrae with placement of implants distant from the site of injury, postoperative adjustability, and complete removal of implants after healing. This study supports the biomechanical stability ESSF of the canine lumbar spine. Further studies are indicated to evaluate zones of consistently safe and secure placement of pins and clinical efficacy.
Effects of Degree of Acetabular Rotation after Triple Pelvic Osteotomy on the Position of the Femoral Head in Relationship to the Acetabulum
Authors: Tomlinson James L. , Cook James L.
Published: August 2002

Objective—To assess the effect of rotating the acetabulum 20° and 30° on percent coverage (PC) of the femoral head by the acetabulum and Norberg angle (NA) after triple pelvic osteotomy (TPO).

Study design—Retrospective study.

Animal Population—Fifty‐six client‐owned dogs.

Methods—PC and NA were measured from preoperative, immediate postoperative, first recheck, and second recheck radiographs to compare the effects of 20° and 30° of rotation of the acetabulum after TPO for treatment of hip dysplasia.

Results—Within the 20° rotation group, PC and NA values were significantly greater at each subsequent evaluation time starting at the preoperative measurement except for NA between the first and second recheck times. Within the 30° rotation group, PC and NA values were significantly greater at each subsequent evaluation time starting at the preoperative measurement except for PC and NA between the first and second recheck times. No significant differences between the 20° and 30° rotation groups were found at any corresponding times for either PC or NA.

Conclusions—Acetabular rotation of 20° provided the same degree of improvement in acetabular femoral head coverage as 30° of rotation after TPO at the immediate postoperative, first recheck, and second recheck evaluation times.

Clinical relevance—Based on PC and NA, 20° rotation of the acetabulum provides as much benefit as 30° of acetabular rotation when performing a TPO.
A Mathematical Model for the Dynamics of Hepatitis C
Authors: Avendano R. , Esteva L. , Flores J. A. , Allen J. L. Fuentes , Gómez G. , López-Estrada Je.
Published: August 2002

We formulate a model to describe the dynamics of hepatitis C virus (HCV) considering four populations: uninfected liver cells, infected liver cells, HCV and T cells. Analysis of the model reveals the existence of two equilibrium states, the uninfected state in which no virus is present and an endemically infected state, in which virus and infected cells are present. There exists a threshold condition that determines the existence and stability of the endemic equilibrium. We discuss the efficacy of the therapy methods for hepatitis C in terms of the threshold parameter. Success of the therapy could possibly be predicted from the early viral dynamics in the patients.
Mitochondrial ROS Metabolism: Modulation by Uncoupling Proteins
Authors: Casteilla L. , Rigoulet M. , Pénicaud L.
Published: August 2002

Most of the oxygen consumed by aerobic organisms is reduced to water by the enzyme cytochrome c oxidase in the terminal reaction of the mitochondrial respiratory chain. A significant proportion of the oxygen molecules are converted to superoxide anion radicals by complexes I and III via a nonenzymatic process. A cascade of enzymes, some of them inside the mitochondria themselves, scavenges superoxide anions in order to protect cells from oxidative damage induced by reactive oxygen species (ROS). Unfortunately, the quantification of the fluxes of mitochondrial ROS inside living cells is currently almost impossible, and this in turn limits our knowledge. Presently, the involvement of mitochondrial ROS can only be demonstrated by indirect strategies and among them knockout techniques are the most convincing. The yield of superoxide generation and subsequently ROS production depend mostly on oxygen concentration but can be efficiently modulated by mitochondrial uncoupling. This role could be assumed in part by one of the Uncoupling Proteins (UCPs). These proteins have coenzyme Q as an obligatory partner and we present here the hypothesis of UCPs as a crucial element of the respiratory chain. ROS have been mostly involved in degenerative processes including ageing. More recently, numerous studies point out the role of ROS as true intracellular second messengers. A putative role of mitochondrial ROS as the sensing element of energy metabolism is discussed here. We propose that UCPs could play a central role in modulation of ROS‐dependent signalling pathways and metabolic sensing via the modulation of ROS generation.
Mitochondrial Calcium Homeostasis: Mechanisms and Molecules
Authors: Vandecasteele Grégoire , Szabadkai György , Rizzuto Rosario
Published: August 2002

Despite the early characterisation of Ca 2+ fluxes in isolated mitochondria and the ability of this ion to up‐regulate dehydrogenases of the Krebs cycle, the low affinity of the organelle uptake pathways was a long‐standing obstacle to the recognition of a physiological role for mitochondrial Ca 2+ uptake. This review begins with a historical account of the main results that proved the contrary and provides a brief description of mitochondrial Ca 2+ signals. Then, it discusses the characteristics of Ca 2+ regulation of mitochondrial function. Finally, it summarizes recent discoveries on structural aspects of mitochondrial reticulum and its connections to signalling partners such as the endoplasmic reticulum or the plasma membrane.
Redox Regulation by Thioredoxin and Thioredoxin‐Binding Proteins
Authors: Nishiyama Akira , Masutani Hiroshi , Nakamura Hajime , Nishinaka Yumiko , Yodoi Junji
Published: August 2002

Recent works have shown the importance of reduction/oxidation (redox) regulation in various biological phenomena. Thioredoxin is a 12‐kDa protein with redox‐active dithiol in the active site ‐Cys‐Gly‐Pro‐Cys‐ and constitutes a major thiol reducing system, the thioredoxin system. Thioredoxin plays multiple roles in cellular processes such as proliferation or apoptosis. It also promotes DNA binding of transcription factors such as NF‐ κB, AP‐1, p53, and PEBP2. Overexpression of thioredoxin suppresses the degradation of I κB and the transactivation of NF‐ κB, whereas overexpression of nuclear‐targeted thioredoxin exhibits the enhancement of NF‐ κB‐dependent transactivation. ASK1, a MAP kinase kinase kinase mediating the TNF‐ α signal has been identified as a thioredoxin binding protein. Thioredoxin shows an inhibitory effect on the TNF‐ α induced activation of ASK1 and p38 MAP kinase pathway. We identified p40phox as the thioredoxin binding protein‐1 (TBP‐1) and vitamin D3 up‐regulated protein 1 (VDUP1) as the thioredoxin binding protein‐2 (TBP‐2) by yeast two‐hybrid system. TBP‐2/VDUP1 negatively regulates the expre and reducing activity of thioredoxin. Thioredoxin interacting proteins may be involved in thioredoxin‐mediating regulation.
Synthesis and Photoresist Property of a Polyamide Containing a Naphthylurea Moiety
Authors: Akimoto Satoshi , Jikei Mitsutoshi , Kakimoto Masa-Aki
Published: August 2002

A novel polyamide containing a naphthylurea moiety as the photoreaction site (Np Urea-PA) was synthesized by polycondensation of N-3, 5-dicarboxyphenyl- N′-1-naphthylurea and 4, 4′-oxydianiline (ODA). The model reactions, which consisted of irradiation by UV light of the low molecular weight aromatic ureas and isocyanate, suggested that the photochemistry involves an aromatic isocyanate intermediate. Np Urea-PA acts as the negativeworking resist, by UV irradiation through a quartz mask followed by development using aprotic solvents such as N, N-dimethylacetamide (DMAc). The contrast of the negative tone image was improved by using 20 wt% of p-xylylenediamine ( pXDA) as a crosslinking agent.
Miscibility, Morphology and Tensile Properties of the Melt Blends of Liquid Crystalline Polyimide (PI-LC) with Two Different Thermoplastic Polyimides: Semicrystalline Polyimide (N-TPI) and Amorphous Poly(Ether-Imide) (PEI)
Authors: Konda M , Tanaka M , Miyamoto M , Kimura Y , Yamaguchi A
Published: August 2002

A liquid crystalline polyimide (poly[1, 3-bis[4-(4-aminophenoxy)-α, α-dimethylbenzyl]benzene pyromellitimide]: PI-LC) was blended with two kinds of thermoplastic polyimide: poly[3, 3′-(4, 4′-dioxybiphenyl)diphenylene pyromellitimide] (N-TPI) which is a semicrystalline polyimide having a melting point of 388 °C and poly[2, 2′-bis(3, 4-dicarboxyphenoxy)phenylpropane-2-phenylene bisimide] (PEI) which is an amorphous poly(etherimide) having a glass transition temperature at 220 °C. The miscibility of N-TPI and PI-LC was evaluated by DSC using enthalpy relaxation, and the phase diagram of their blend was drawn above the melting point of N-TPI. The result indicated that the PI-LC-rich blend was miscible in a wide range of compositions. However, the extruded samples of their blend, which had been prepared under a flow of high shear, showed a phase separation structure. In the other combination of PEI and PI-LC, the blend was immiscible, but at low composition of PI-LC their blend fibre showed higher tensile properties than the original PEI fibre.
DMTA Studies of the Effect of Storage Time on the Curing Process of Sheet Moulding Compound
Authors: Hamdan S , Hashim D M A , Fong S W
Published: August 2002

The application of the dynamic mechanical thermal analysis (DMTA) test method in the study of the effect of storage time on the curing process of sheet moulding compound (SMC) is discussed. Emphasis is placed on following the curing by the study of storage modulus and loss tangent with storage time. Changes in the storage time showed an increase in the storage modulus (log E′) during a room-temperature cure. The loss tangent (tan δ) damping peak occurs as the system is driven into the glassy state by the cross-linking reaction. The SMC displayed a room-temperature log E′ of 8.5 Pa which increased to approximately 9 Pa in the subsequent scan in the DMTA.
Anomalies between Microwave and Thermal Cure Kinetics of Epoxy-Amine Resin Systems
Authors: Rogers D G , Marand E , Hill D J T , George G A
Published: August 2002

The cure of the epoxy systems MY721/27% DDS at 160 °C and MY721/32% DDM at 120 °C have been investigated in both rectangular and cylindrical microwave cavities and thermally. The cure rates were monitored by FT-NIR spectroscopy over the region 4750–7250 cm-1. The rates of cure in the microwave cavities, estimated from both the primary and epoxy group concentrations, were found to be different, and different from the rate observed for thermal cure in a heated aluminium block. This anomalous behaviour has been attributed to spatial inhomogeneity in the temperature of the epoxy samples, arising from inhomogeneity in the microwave field in the cavity, rather than to specific absorptions of the microwave radiation by the reactive groups in the epoxy samples, as has been suggested previously by some other authors.