Biomedical subjects
Publications and source records attributed to A Cuschieri.
We report a case of an important and uncommon cause of vomiting in an elderly female patient who had no previous apparent gastrointestinal problems. A diaphragmatic hernia with gastric volvulus, which presented non-specifically but was an important diagnosis to make.
Surgical operative performance is currently assessed by audit of morbidity, mortality and, especially in patients with cancer, in terms of long-term outcome. Its chief merit is the identification of problems and sub-optimal results by individual surgeons/centres. There is one aspect of audit that constitutes its intrinsic weakness, the verdict on performance it gives is always retrospective--the problem is identified because of the bad results thrown up by analysis of the data. As a result, there is a distinct possibility that surgeons might exclude patients with potentially curative conditions because of increased operative risk due to co-morbid disease from major surgery because of a fear, conscious or otherwise, of comparative under-performance. There is a methodology in established use by industry that is both prospective and prescriptive in ensuring optimal performance--human reliability assessment (HRA), which can be translated into clinical practice. This paper explains the nature of HRA and reports on its initial use in surgery.
Laparoscopic treatment of ductal calculi in experienced hands is more successful and incurs a shorter hospital stay and overall costs than current orthodox two-stage management (endoscopic stone extraction followed by cholecystectomy). The results of large series of laparoscopic ductal stone clearance report a median success rate of 90%, a mortality under 1%, and a missed stone rate of 0.8% to 4%. Thus the case for routine preoperative endoscopic stone extraction is no longer sustainable and this management option should be reserved for patients with cholangitis, severe gallstone-associated pancreatitis, and for patients considered unfit for surgery and general anesthesia. The remaining issues concern standardization of the techniques of laparoscopic ductal stone extraction and the intraoperative management algorithm with agreed indications for transcystic extraction versus direct common bile duct (CBD) exploration. Narrowed bile ducts should not be explored directly, and if the transcystic laparoscopic approach fails in these cases, endoscopic extraction is the safest option, either at the time of surgery under the same anesthetic or during the postoperative period. The insertion of a T-tube after direct common duct exploration detracts considerably from the benefits of the laparoscopic approach, and primary closure with either a cystic duct drainage cannula or by means of a temporary endobiliary stent is recommended.
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This experimental study was designed to investigate the risk of tumor dissemination by hepatic cryosurgery and to determine the final subzero temperature required for effective hepatic tumor cryoablation. Although cryosurgery is now one of the established modalities for the treatment of some liver tumors and has been used for two decades, controversy remains regarding the final subzero temperature needed to destroy tumor masses. One experimental report has indicated that hepatic cryosurgery may enhance tumor dissemination. For this study, rat hepatic tumors were produced by direct injection of rat colonic carcinoma cells (DHD/K12/TRb). The control untreated animals (n = 12) were sacrificed after induction of liver tumors at 4 and 6 weeks. The animals in the treatment group (n = 16) underwent cryosurgery 2 weeks after tumor induction and were allowed to recover before sacrifice 2 and 4 weeks later. Pulmonary metastases were identified in 9 of 12 (75%) control animals at postmortem examination (2 and 6 weeks after tumor inoculation) and in 6 of 16 (38%) rats in the treatment group at sacrifice 2 and 4 weeks after cryosurgery (p = 0.11, Fisher's test for unpaired analysis). Peritoneal deposits were observed in 5 of 12 (42%) control animals at postmortem examination and in 8 of 16 (50%) of the treated animals at the time of cryosurgery (p = 0.95, Fisher's test for unpaired analysis). Two other study animals developed deposits after cryosurgery. The prevalence of peritoneal deposits in the study group was not altered by cryosurgery (p = 0.5, McNemar's test for paired analysis). The importance of the final subzero temperature at the edge of the iceball during tumor ablation by cryosurgery was confirmed by the histologic findings. Complete ablation with no residual viable tumor was obtained only when the subzero temperature had reached -38 degrees C or below. The results of this study do not support the suggestion that hepatic cryosurgery enhances tumor dissemination. The findings also confirm that a subzero temperature at the edge of the iceball of -38 degrees C or lower is necessary to ensure complete ablation of tumor.
Endoscopic adrenalectomy has been recommended for the treatment of several benign adrenal diseases. The safety of this procedure largely depends on a careful surgical dissection and appropriate hemostatic technique. An established slipknotting technique was employed to control the main adrenal vein in a consecutive series of 14 patients undergoing endoscopic adrenalectomy. The operative steps to ligate the adrenal pedicle are described. A Medline search also was conducted to identify all reported bleeding episodes associated with this procedure. All attempted ligatures of the main adrenal vein were completed successfully by the described technique, and none of our patients required perioperative blood transfusion. Twenty-eight episodes of bleeding collected from the literature were analyzed. Hemorrhagic accidents related to dislodgement of clips were documented at least in three patients. The cause of bleeding was unspecified in 10 patients. Extracorporeal ligation of the main adrenal vein is feasible, safe, and advisable to prevent the occurrence of hemorrhage during endoscopic adrenalectomy.
BACKGROUND: The location of the optical port and the choice of endoscope determine the angle subtended between the optical axis of the endoscope and the plane of the operation target: the optical axis-to-target view (OATV) angle. The aim of the study was to investigate the influence OATV angle on endoscopic task performance. METHODS: The Dundee Endoscopic Psychomotor Tester was used for objective assessment of endoscopic task performance. Ten surgeons carried out a standard task with the optical axis of the endoscope subtending 90 degrees, 75 degrees, 60 degrees and 45 degrees to the target surface. Each subject underwent three test sessions. Each session consisted of one run with each of the OATV angles in a random order. The outcome measures were the errors rate, the execution time, and the force applied on the target. RESULTS: The 90 degrees OATV angle had the best accuracy, the shortest execution time, and the lowest force applied on the back plate. The errors rate increased from 17% with the 90 degrees OATV angle to 79% with the 45 degrees angle. There was a significant increase in execution time and force with the decrease in the OATV angle (p < 0.0001). CONCLUSIONS: The best task performance is obtained when the optical axis of the endoscope is perpendicular to the target plane.
With the development of endoscopic surgery, new hazards of high-frequency (HF) electrosurgery have been recognized. The potential risks of monopolar electrosurgery, the limitations of bipolar technique, and the need to reduce instrument interchange have favored the use of ultrasonic technology, which becomes more and more popular. This work aims at presenting the main features of the currently available ultrasonically activated scalpels, as well as their advantages, limitations, and indications.
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BACKGROUND: There are times during endoscopic procedures when the surgeon has to operate ahead of the camera/telescope assembly. As a result, the image displayed on the monitor will be an inverted mirror image of the operative field (reverse alignment). The present study addresses the extent of these difficulties and suggests some techniques that may be used to overcome the problem. METHODS: Eight specialist registrars participated in experiments involving the execution of a simulated dissection task under 12 different imaging conditions. These conditions included normal alignment, reverse alignment, total or partial digital correction of reverse alignment (about the horizontal and vertical axes independently and together), and a simple rotation of the camera through 180 degrees. Normal, reverse, and corrected reverse alignment were also tested with optical axes of 45 degrees and 60 degrees. The endpoints were the task execution and the errors rate. RESULTS: A marked deterioration in execution time was observed when the surgeons worked under reverse alignment rather than under normal viewing (p = 0.036). Significant improvement in execution-time errors rate was found when both the horizontal and vertical axes were digitally corrected simultaneously (p = 0.27) and when the camera was rotated 180 degrees with respect to the telescope during reverse alignment (p = 0.28). CONCLUSIONS: The effect on performance produced by reverse alignment of the endoscope and instruments can be overcome by means of digital electronic processing, or simply by turning the camera through 180 degrees.
BACKGROUND: The design of the handle on instruments for endoscopic surgery determines comfort and efficiency of use by the surgeon. This applies particularly to needle drivers. METHODS: A novel rocker handle was designed to provide holding comfort and intuitive function. This rocker handle was compared with a finger-loop handle in a study involving 10 surgeons who tied a total of 360 intracorporeal surgeons' knots in a random sequence. The end points in this study were the execution time, knot quality, and motion analysis parameters of the surgeon's elbow and shoulder joints. RESULTS: Intracorporeal surgeon's knots tied with the rocker-handle driver exhibited a better knot quality, although this was not significant (p = 0.097). A significant improvement in the knot quality score (KQS) was observed between the first and the second sessions (p = 0.045) with the rocker handle, whereas no significant learning effect was observed for the finger-loop handle. During intracorporeal knot tying, the angular velocity at the elbow and shoulder joints was consistently lower with the rocker handle, suggesting that more controlled movements are enacted by the surgeon with this handle. Discomfort from finger-loop pressure on the thumb was reported by 3 of 10 surgeons with the finger-loop handle, whereas no discomfort was reported for the rocker handle. CONCLUSIONS: The new rocker handle improves the quality of task performance by eliminating discomfort and reducing angular velocities at the shoulder and elbow joints during use.
BACKGROUND: The current management of patients with gallstone disease and ductal calculi consists of endoscopic stone extraction (ESE) followed by laparoscopic cholecystectomy (LC). Following the advent of techniques of laparoscopic ductal stone clearance, an alternative single-stage laparoscopic treatment was introduced for these patients. The European Association of Endoscopic Surgery (E.A. E.S.) set up a ductal stone trial to compare the relative efficacy and outcome of these two management options. METHODS: A prospective randomized controlled clinical trial compared two management options. Group A (n = 150) received preoperative endoscopic retrograde cholangiography (ERC) with ESE followed by LC during the same hospital admission, and group B (n = 150) received single-stage laparoscopic management. RESULTS: There were no significant differences between the two groups in the clinical demographic details and the pretreatment biochemical findings. In group A, 14 of 150 patients received single-stage treatment; in group B, 17 of 150 were managed by the two-stage approach (protocol violation = 31/300, 10%). In group A patients managed in accordance with randomization, ERC was successful in 129/136 (95%) and preoperative ESE succeeded in 82/98 (84%) with ductal calculi detected by the ERC. Two patients had malignancies and one refused surgery. Thus, 133 patients underwent surgery. Of this group, 116 had LC only and 17 had LC and attempted laparoscopic duct exploration. There were eight conversions to open surgery (6%), 17 complications for both stages (12.8%), and two postoperative deaths (1.5%). In group B patients managed in accordance with randomization, intraoperative cholangiography was successful in 132/133 (99%). Twenty-one (16%) had normal findings, ductal calculi were found in 109, and other pathology was noted in two (periampullary cancer, severe pancreatitis). These two patients and one other (who had gross adhesion in the triangle of Calot) were converted at the start of the procedure. Transcystic ductal stone clearance was successful in 45 of 56 patients (80%), and laparoscopic direct common duct (CBD) exploration was successful in 47 of 55 patients (85%). This group includes 53 patients who underwent primary direct exploration and two failed attempts at transcystic extraction. The conversion rate was 13%. Postoperative complications were encountered in 21 patients (15.8%), and one patient died of a major myocardial infarction (0. 75%). The one postoperative death and the 10/11 biliary complications occurred in the laparoscopic supraduodenal CBD exploration subgroup. The conversion rate was higher in group B (17 vs eight; p = 0.08). Laparotomy in the postoperative period was required in three patients in group A and four patients in group B. The group B patients were in hospital for 3 days less than patients who had two-stage management (median, 6.0, IQR = 4.25-12 vs median, 9.0, IQR = 5.5-14; p < 0.05). CONCLUSIONS: The results demonstrate equivalent success rates and patient morbidity for the two management options but a significantly shorter hospital stay with the single-stage laparoscopic treatment. The findings indicate that in fit patients (ASA I and II), single-stage laparoscopic treatment is the better option, and preoperative ESE should be confined to poor-risk patients-i.e., those with cholangitis or severe pancreatitis.
BACKGROUND: This work was undertaken to evaluate the concurrent and predictive validity of the Advanced Dundee Endoscopic Psychomotor Tester (ADEPT) for clinical competence in endoscopic manipulations. METHOD: Ten specialist registrars completed 200 structured tasks on ADEPT involving manipulation of switches and dials using standard endoscopic imaging and surgical instruments. This performance was correlated with blind ratings on clinical endoscopic operative competence by four consultant surgeons. RESULTS: The learning curve on the use of the ADEPT was quick, proficiency in using the system was achieved by all candidates after 20 tasks by the end of the first run when the individual's performance reached its peak. Individual error rates did not improve from the start. A high correlation (0.909) was observed between success rates on ADEPT tasks and error rates. The overall performance on ADEPT correlated well with independent blind assessment of clinical competence (r = 0.789) as did the number of error-free runs (r = 0.740). CONCLUSIONS: The study confirms a good correlation between performance on ADEPT and independent consultant clinical assessment of operative skills (concurrent validity). The system identifies aspects of performance that do not improve with practice (innate abilities) and thus could be used to predict ultimate level of operative skill. If confirmed by larger studies, ADEPT could be used as an aptitude tester for trainee selection in minimal access surgery and interventional radiology. By providing objective feedback on task performance, the system facilitates reflective skill acquisition and its assessment by trainees.
Controversy still exists on the optimal surgical resection for potentially curable gastric cancer. Much better long-term survival has been reported in retrospective/non-randomized studies with D2 resections that involve a radical extended regional lymphadenectomy than with the standard D1 resections. In this paper we report the long-term survival of patients entered into a randomized study, with follow-up to death or 3 years in 96% of patients and a median follow-up of 6.5 years. In this prospective trial D1 resection (removal of regional perigastric nodes) was compared with D2 resection (extended lymphadenectomy to include level 1 and 2 regional nodes). Central randomization followed a staging laparotomy. Out of 737 patients with histologically proven gastric adenocarcinoma registered, 337 patients were ineligible by staging laparotomy because of advanced disease and 400 were randomized. The 5-year survival rates were 35% for D1 resection and 33% for D2 resection (difference -2%, 95% CI = -12%-8%). There was no difference in the overall 5-year survival between the two arms (HR = 1.10, 95% CI 0.87-1.39, where HR > 1 implies a survival benefit to D1 surgery). Survival based on death from gastric cancer as the event was similar in the D1 and D2 groups (HR = 1.05, 95% CI 0.79-1.39) as was recurrence-free survival (HR = 1.03, 95% CI 0.82-1.29). In a multivariate analysis, clinical stages II and III, old age, male sex and removal of spleen and pancreas were independently associated with poor survival. These findings indicate that the classical Japanese D2 resection offers no survival advantage over D1 surgery. However, the possibility that D2 resection without pancreatico-splenectomy may be better than standard D1 resection cannot be dismissed by the results of this trial.
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BACKGROUND AND STUDY AIMS: Radiofrequency (RF) thermal ablation has been applied almost exclusively through the percutaneous approach under radiological/external ultrasound guidance. We have embarked on a programme of laparoscopic ultrasound-guided RF ablation of hepatic tumours in view of the potential advantages of this approach, i. e. reduced heat sink effect, greater precision and improved assessment of the thermal ablative zone. PATIENTS AND METHODS: RF thermal ablation using the Zomed International generator and multielectrode probes in two patients with hepatoma arising on a background of cirrhosis and in eight patients with multiple deposits from primary colorectal cancer. RESULTS: Total ablation was performed in two patients with hepatoma and 7/8 patients with secondary deposits. Total ablation with a minimum of 0.5-cm margin was achieved in 32 lesions. No complications were encountered postoperatively and all patients were discharged within 2 days of the intervention. One patient in whom thermal ablation was not completed has since died of progressive disease, eight appear to be free of tumour (follow-up 6-20 months) but one patient has developed further secondary hepatic deposits. CONCLUSIONS: The initial experience with laparoscopic ultrasound-guided RF ablation of hepatic tumours indicates its safety and therapeutic potential in patients with inoperable hepatic tumours.