Proving the Effectiveness of the Fundamentals of Robotic Surgery (FRS) Skills Curriculum: A Single-blinded, Multispecialty, Multi-institutional Randomized Control Trial

OBJECTIVE

To demonstrate the noninferiority of the fundamentals of robotic surgery (FRS) skills curriculum over current training paradigms and identify an ideal training platform.

SUMMARY BACKGROUND DATA

There is currently no validated, uniformly accepted curriculum for training in robotic surgery skills.

METHODS

Single-blinded parallel-group randomized trial at 12 international American College of Surgeons (ACS) Accredited Education Institutes (AEI). Thirty-three robotic surgery experts and 123 inexperienced surgical trainees were enrolled between April 2015 and November 2016. Benchmarks (proficiency levels) on the 7 FRS Dome tasks were established based on expert performance. Participants were then randomly assigned to 4 training groups: Dome (n = 29), dV-Trainer (n = 30), and DVSS (n = 32) that trained to benchmarks and control (n = 32) that trained using locally available robotic skills curricula. The primary outcome was participant performance after training based on task errors and duration on 5 basic robotic tasks (knot tying, continuous suturing, cutting, dissection, and vessel coagulation) using an avian tissue model (transfer-test). Secondary outcomes included cognitive test scores, GEARS ratings, and robot familiarity checklist scores.

RESULTS

All groups demonstrated significant performance improvement after skills training (P < 0.01). Participating residents and fellows performed tasks faster (DOME and DVSS groups) and with fewer errors than controls (DOME group; P < 0.01). Inter-rater reliability was high for the checklist scores (0.82-0.97) but moderate for GEARS ratings (0.40-0.67).

CONCLUSIONS

We provide evidence of effectiveness for the FRS curriculum by demonstrating better performance of those trained following FRS compared with controls on a transfer test. We therefore argue for its implementation across training programs before surgeons apply these skills clinically.

Multicentre observational study of surgical system failures in aortic procedures and their effect on patient outcomes

BACKGROUND

Vascular surgical care has changed dramatically in recent years with little knowledge of the impact of system failures on patient safety. The primary aim of this multicentre observational study was to define the landscape of surgical system failures, errors and inefficiency (collectively termed failures) in aortic surgery. Secondary aims were to investigate determinants of these failures and their relationship with patient outcomes.

METHODS

Twenty vascular teams at ten English hospitals trained in structured self-reporting of intraoperative failures (phase I). Failures occurring in open and endovascular aortic procedures were reported in phase II. Failure details (category, delay, consequence), demographic information (patient, procedure, team experience) and outcomes were reported.

RESULTS

There were strong correlations between the trainer and teams for the number and type of failures recorded during 88 procedures in phase I. In 185 aortic procedures, teams reported a median of 3 (i.q.r. 2-6) failures per procedure. Most frequent failures related to equipment (unavailability, failure, configuration, desterilization). Most major failures related to communication. Fourteen failures directly harmed 12 patients. Significant predictors of an increased failure rate were: endovascular compared with open repair (incidence rate ratio (IRR) for open repair 0·71, 95 per cent c.i. 0·57 to 0·88; P = 0·002), thoracic aneurysms compared with other aortic pathologies (IRR 2·07, 1·39 to 3·08; P < 0·001) and unfamiliarity with equipment (IRR 1·52, 1·20 to 1·91; P < 0·001). The major failure total was associated with reoperation (P = 0·011), major complications (P = 0·029) and death (P = 0·027).

CONCLUSION

Failure in aortic procedures is frequently caused by issues with team-working and equipment, and is associated with patient harm. Multidisciplinary team training, effective use of technology and new-device accreditation may improve patient outcomes.

Quantitative analysis of technological innovation in minimally invasive surgery

BACKGROUND

In the past 30 years surgical practice has changed considerably owing to the advent of minimally invasive surgery (MIS). This paper investigates the changing surgical landscape chronologically and quantitatively, examining the technologies that have played, and are forecast to play, the largest part in this shift in surgical practice.

METHODS

Electronic patent and publication databases were searched over the interval 1980-2011 for ('minimally invasive' OR laparoscopic OR laparoscopy OR 'minimal access' OR 'key hole') AND (surgery OR surgical OR surgeon). The resulting patent codes were allocated into technology clusters. Technology clusters referred to repeatedly in the contemporary surgical literature were also included in the analysis. Growth curves of patents and publications for the resulting technology clusters were then plotted.

RESULTS

The initial search revealed 27,920 patents and 95,420 publications meeting the search criteria. The clusters meeting the criteria for in-depth analysis were: instruments, image guidance, surgical robotics, sutures, single-incision laparoscopic surgery (SILS) and natural-orifice transluminal endoscopic surgery (NOTES). Three patterns of growth were observed among these technology clusters: an S-shape (instruments and sutures), a gradual exponential rise (surgical robotics and image guidance), and a rapid contemporaneous exponential rise (NOTES and SILS).

CONCLUSION

Technological innovation in MIS has been largely stagnant since its initial inception nearly 30 years ago, with few novel technologies emerging. The present study adds objective data to the previous claims that SILS, a surgical technique currently adopted by very few, represents an important part of the future of MIS.

Development of a virtual reality training curriculum for phacoemulsification surgery

PURPOSE

Training within a proficiency-based virtual reality (VR) curriculum may reduce errors during real surgical procedures. This study used a scientific methodology to develop a VR training curriculum for phacoemulsification surgery (PS).

PATIENTS AND METHODS

Ten novice-(n) (performed <10 cataract operations), 10 intermediate-(i) (50-200), and 10 experienced-(e) (>500) surgeons were recruited. Construct validity was defined as the ability to differentiate between the three levels of experience, based on the simulator-derived metrics for two abstract modules (four tasks) and three procedural modules (five tasks) on a high-fidelity VR simulator. Proficiency measures were based on the performance of experienced surgeons.

RESULTS

Abstract modules demonstrated a 'ceiling effect' with construct validity established between groups (n) and (i) but not between groups (i) and (e)-Forceps 1 (46, 87, and 95; P<0.001). Increasing difficulty of task showed significantly reduced performance in (n) but minimal difference for (i) and (e)-Anti-tremor 4 (0, 51, and 59; P<0.001), Forceps 4 (11, 73, and 94; P<0.001). Procedural modules were found to be construct valid between groups (n) and (i) and between groups (i) and (e)-Lens-cracking (0, 22, and 51; P<0.05) and Phaco-quadrants (16, 53, and 87; P<0.05). This was also the case with Capsulorhexis (0, 19, and 63; P<0.05) with the performance decreasing in the (n) and (i) group but improving in the (e) group (0, 55, and 73; P<0.05) and (0, 48, and 76; P<0.05) as task difficulty increased.

CONCLUSION

Experienced/intermediate benchmark skill levels are defined allowing the development of a proficiency-based VR training curriculum for PS for novices using a structured scientific methodology.

Systematic review of predictors of surgical performance

Background

Selection criteria for surgical training are not scientifically proven. There is a need to define which attributes predict future surgical performance. The aim of this study was to examine the predictive value of specific attributes that impact on surgical performance.

Methods

All studies assessing the predictive power of specified attributes with regard to outcome measures of surgical performance in MEDLINE, Embase, the Cochrane Central Register of Controlled Trials and Educational Resources Information Centre databases, and bibliographies of selected articles from 1950 to November 2010 were considered for inclusion by two independent reviewers. Information on study identifiers, participant characteristics, predictors assessed, evaluation methods for predictors, outcome measures, results and statistical analysis was collected. Quality assessment was carried out using the Hayden criteria.

Results

Visual–spatial perception correlated with both subjective and objective assessments of surgical performance, including rate of skill acquisition. Visual–spatial perception did not correlate with operative ability in experts, although it did with operative ability at the end of a training programme. Psychomotor aptitude, assessed collectively, correlated with rate of skill acquisition. Academic achievement predicted completion of a training programme and passing end-of-training examinations, but did not predict clinical performance during the training programme.

Conclusion

Intermediate- and high-level visual–spatial perception, as well as psychomotor aptitude, can be used as criteria for assessing candidates for surgical training. Academic achievement is an effective predictor of successful completion of training programmes and should continue to form part of the assessment of surgical candidates.

Inflammation of the residual appendix stump: a systematic review

AIM

A systematic review of the literature was undertaken to examine reported cases of stump appendicitis (SA) to determine the relationship between SA and the original operative strategy (open vs laparoscopic), and to evaluate the clinical features and diagnosis.

METHOD

A Pub-med search was conducted to identify cases of appendicitis of a residual stump following appendicectomy. Two original cases of SA following laparoscopic appendicectomy treated in our own hospitals are also included in the analysis. Sixty cases of SA reported in the English medical literature were analysed.

RESULTS

The interval from the original appendicectomy ranged from 4 days to 50 years. SA followed appendicectomy in 58% of open and 31.6% of laparoscopic procedures. SA was frequently misdiagnosed as constipation or gastroenteritis, with a significant delay to surgery. Computerized tomography diagnosed SA in 46.6% of cases. Perforation with gangrene of the stump occurred in 40%.

CONCLUSION

Stump appendicitis is rare. It may complicate open or laparoscopic appendicectomy. A high level of suspicion should be maintained in any patient with right sided abdominal pain and a history of prior appendicectomy.

Elective colonic surgery for cancer in the elderly: an investigation into postoperative mortality in English NHS hospitals between 1996 and 2007

BACKGROUND

This study was primarily aimed to quantify perioperative mortality risk in elderly patients undergoing elective colonic resectional surgery. In addition, the safety of minimally invasive colonic surgery in this patient group was evaluated.

METHODS

All patients aged > 75 undergoing elective colonic resection for colorectal malignancy between 1996 and 2007 in English NHS hospitals were included from the Hospital Episode Statistics (HES) dataset.

RESULTS

Between the study dates, 28,746 patients > 75 years underwent elective colonic resection. The national annual number of colonic excisions carried out amongst elderly patients increased from 2188 patients in 1996/7 to 3240 patients in 2006/7. Following adjustment for gender, comorbidity and surgical approach, advancing age was an independent predictor for 30-day mortality (OR 2.47 for patients aged 85-89 vs 75-79, P < 0.001). Use of laparoscopy was a significant predictor of reduced perioperative mortality (OR 0.56, P = 0.003) once adjusted for advancing age, gender and comorbidity. Comparison of 30-day and 1-year postoperative mortality following elective colonic resection in patients aged 90 revealed a large excess of patients dying outside of the immediate perioperative period (10.1% and 26.2% for proximal cancers, respectively; 12.9% and 36.1% for distal colonic resections, respectively).

CONCLUSIONS

Advancing age is an independent risk factor for postoperative death in elderly patients undergoing elective colonic resection for cancer. The risk of death in the elderly is extremely high and surgical decision-making should incorporate the mortality risk that occurs outside the immediate perioperative period. In this national series, patients selected for a laparoscopic procedure were at lower risk of perioperative death than those undergoing the conventional approach.

Concurrent colorectal malignancy and abdominal aortic aneurysm: a multicentre experience and review of the literature

OBJECTIVES

There is lack of consensus regarding concurrent vs. staged approaches, and the prioritisation of staged procedures in cases presenting with colorectal carcinoma (CRC) and abdominal aortic aneurysm (AAA) synchronously. We aim to present our experience, review the literature on this therapeutic dilemma and examine the role of endovascular aortic repair (EVAR).

DESIGN, MATERIALS AND METHODS

An observational study of the experience of two centres and a systematic review of the published literature.

RESULTS

Twenty-four patients were identified from the prospective databases of two tertiary referral centres between 2001 and 2006. Intervention for both malignancy and aneurysm was performed in 13 patients. In 10 patients, cancer resection was performed initially and was followed by open aneurysm repair (n=3) or EVAR (n=7). Two patients (AAA diameters: 7.0 and 8.0cm) underwent EVAR prior to colonic resection. One patient was selected for synchronous surgery. There were no interval AAA ruptures, graft infection or postoperative mortalities. Literature review identified 269 such cases; of these 101 were treated by combined surgery. In staged surgery, there were nine interval aneurysmal ruptures and one aortic graft infection.

CONCLUSIONS

In our experience, staged management can be undertaken, without interval aneurysmal rupture. EVAR has an evolving role in preventing delay in CRC management, in high-risk patients, and during combined intervention.

Validation of orthopaedic bench models for trauma surgery

The aim of this study was to validate the use of three models of fracture fixation in the assessment of technical skills. We recruited 21 subjects (six experts, seven intermediates, and eight novices) to perform three procedures: application of a dynamic compression plate on a cadaver porcine model, insertion of an unreamed tibial intramedullary nail, and application of a forearm external fixator, both on synthetic bone models. The primary outcome measures were the Objective Structural Assessment of technical skills global rating scale on video recordings of the procedures which were scored by two independent expert observers, and the hand movements of the surgeons which were analysed using the Imperial College Surgical Assessment Device. The video scores were significantly different for the three groups in all three procedures (p < 0.05), with excellent inter-rater reliability (alpha = 0.88). The novice and intermediate groups specifically were significantly different in their performance with dynamic compression plate and intramedullary nails (p < 0.05). Movement analysis distinguished between the three groups in the dynamic compression plate model, but a ceiling effect was demonstrated in the intramedullary nail and external fixator procedures, where intermediates and experts performed to comparable standards (p > 0.6). A total of 85% (18 of 21) of the subjects found the dynamic compression model and 57% (12 of 21) found all the models acceptable tools of assessment. This study has validated a low-cost, high-fidelity porcine dynamic compression plate model using video rating scores for skills assessment and movement analysis. It has also demonstrated that Synbone models for the application of and intramedullary nail and an external fixator are less sensitive and should be improved for further assessment of surgical skills in trauma. The availability of valid objective tools of assessment of surgical skills allows further studies into improving methods of training.

WITHDRAWN: Meta-analysis: the use of adhesion prevention membranes in abdominal surgery

Ahead of Print article withdrawn by publisher.

Apoptosis and chemo-resistance in colorectal cancer

Systemic chemotherapy plays an integral part in treating advanced colorectal cancer. However 50% of patients respond poorly or have disease progression due to resistance to chemotherapeutic agents. This article reviews the pathways that regulate apoptosis, apoptotic mechanisms through which chemotherapeutic agents mediate their effect and how deregulation of apoptotic proteins may contribute to chemo-resistance. Also discussed are potential therapeutic strategies designed to target these proteins and thereby improve response rates to chemotherapy in colorectal cancer.

Diagnostic precision of magnetic resonance imaging for preoperative prediction of the circumferential margin involvement in patients with rectal cancer

OBJECTIVE

Circumferential margin involvement (CMI) is an important prognostic indicator for patients with rectal cancer. This meta-analysis aims at evaluating the diagnostic precision of magnetic resonance imaging (MRI) for the preoperative evaluation of CMI in patients with rectal cancer.

METHOD

Quantitative meta-analysis was performed comparing MRI against histology after total mesorectal excision. Sensitivity, specificity and diagnostic odds ratio (DOR) were calculated for each study. Summary receiver operating characteristic (SROC) curves and subgroup analysis were undertaken. Study quality and heterogeneity were evaluated. Meta-regression meta-analysis was used to evaluate the significance of the difference in relative DORs.

RESULTS

Nine studies evaluating 529 patients were included. Pooled results showed an overall sensitivity and specificity for MRI detecting CMI preoperatively of 94% and 85% respectively. The SROC analysis demonstrated an overall weighted area under the curve (AUC) of 0.92 (DOR 57.21, 95% CI 18.21-179.77), without significant heterogeneity between the studies (Q-value 14.66, P = 0.06). Good study quality further increased the sensitivity and specificity of MRI. The use of a 1.5 Tesla coil, a phased array coil and the inclusion of two interpreters also resulted in high preoperative diagnostic precision. Meta-regression meta-analysis showed a significant difference in the DOR for studies published in or since 2003 (P = 0.019).

CONCLUSION

Magnetic resonance imaging can accurately predict CMI preoperatively for rectal cancer in single units and this is reproducible across different centres. This strategy has important implications for selection of patients for adjuvant therapy prior to surgery.

Meta-analysis of short-term and long-term outcomes of J, W and S ileal reservoirs for restorative proctocolectomy

OBJECTIVE

The choice of ileal pouch reservoir has been a contentious subject with no consensus as to which technique provides better function. This study aimed to compare short- and long-term outcomes of three ileal reservoir designs.

METHOD

Comparative studies published between 1985 and 2000 of J, W and S ileal pouch reservoirs were included. Meta-analytical techniques were employed to compare postoperative complications, pouch failure, and functional and physiological outcomes. Quality of life following surgery was also assessed.

RESULTS

Eighteen studies, comprising 1519 patients (689 J pouch, 306 W pouch and 524 S pouch) were included. There was no significant difference in the incidence of early postoperative complications between the three groups. The frequency of defecation over 24 h favoured the use of either a W or S pouch [J vs S: weighted mean difference (WMD) 1.48, P < 0.001; J vs W: WMD 0.97, P = 0.01]. The S pouch was associated with an increased need for pouch intubation (S vs J: OR 6.19, P = 0.04). The use of a J pouch was associated with a significantly higher prevalence of use of anti-diarrhoeal medication (J vs S: OR 2.80, P = 0.01; J vs W: OR 3.55, P < 0.001).

CONCLUSION

All three reservoirs had similar perioperative complication rates. The S pouch was associated with the need for anal intubation. There was less frequency and less need for antidiarrhoeal agents with the W rather than the J pouch.

Magnetic resonance colonography vs computed tomography colonography for the diagnosis of colorectal cancer: an indirect comparison

OBJECTIVE

The primary aim of this study was to use meta-regression techniques to compare the diagnostic accuracy of computed tomography colonography (CTC) and magnetic resonance colonography (MRC), compared with conventional colonoscopy for patients presenting with colorectal cancer (CRC).

METHOD

Quantitative meta-analysis was performed using prospective studies reporting comparative data between CTC and MRC individually to conventional colonoscopy. Study quality was assessed and sensitivities, specificities, diagnostic odds ratios (DOR) were calculated. Summary receiver operating characteristic (SROC) curves and sensitivity analysis were utilized. Meta-regression was used to indirectly compare the two modalities following adjustment for patient and study characteristics.

RESULTS

Overall sensitivity and specificity for CTC (0.96, 95% CI 0.92-0.99; 1.00, 95% CI 0.99-1.00 respectively) and MRC (0.91, 95% CI 0.79-0.97; 0.98, 95% CI 0.96-0.99 respectively) for the detection of CRC was similar. Meta-regression analysis showed no significant difference in the diagnostic accuracy of both modalities (beta=-0.64, P=0.37 and 95% CI of 0.12-2.39). Both tests showed high area under the SROC curve (CTC=0.99; MRC=0.98), with high DORs (CTC=1461.90, 95% CI 544.89-3922.30; MRC=576.41, 95% CI 135.00-2448.56). Factors that enhanced the overall accuracy of MRC were the use intravenous contrast, faecal tagging and exclusion of low-quality studies. No factors improved diagnostic accuracy from CTC except studies with more than 100 patients (AUC=1.00, DOR=2938.35, 95%CI 701.84-12 302.91).

CONCLUSION

This meta-analysis suggested that CTC and MRC have similar diagnostic accuracy for detecting CRC. Study quality, size and intravenous/intra-luminal contrast agents affect diagnostic accuracies. For an exact comparison to be made, studies evaluating CTC, MRC and colonoscopy in the same patient cohort would be necessary.

Meta-analysis: Alvimopan vs. placebo in the treatment of post-operative ileus

BACKGROUND

Alvimopan is a selective, competitive mu-opioid receptor antagonist with limited oral bioavailability which may be used to reduce length of post-operative ileus.

AIM

The study compared alvimopan with placebo following bowel resection or total abdominal hysterectomy.

METHODS

A meta-analysis of randomized-controlled trials published between 2001 and 2006 of alvimopan vs. placebo was performed. The primary efficacy end-points were composite measures of passage of flatus, stool, and tolerance of solid food (GI-3) and passage of stool and tolerance of solid food (GI-2). The incidence of treatment emergent adverse events was assessed.

RESULTS

Five trials matched the selection criteria, reporting on 2195 patients. A total of 1521 (69.3%) had alvimopan and 674 (30.7%) placebo. GI-3 significantly improved (hazard ratio 1.30; 95% confidence intervals 1.16, 1.45, P < 0.001), as did GI-2 (hazard ratio 1.61; 95% confidence intervals 1.26, 2.05, P < 0.001) on alvimopan 12 mg. Time to discharge (hazard ratio 1.26; 95% confidence intervals 1.13, 1.40, P < 0.001), time to bowel motion (hazard ratio 1.74; 95% confidence intervals 1.29, 2.35, P < 0.001), and time to solid food (hazard ratio 1.14; 95% confidence intervals 1.01, 1.30, P < 0.04) also improved significantly. No difference was noted in the incidence of treatment emergent adverse events.

CONCLUSIONS

Alvimopan showed significant advantages over placebo in restoring gastro-intestinal function, and reduced time to discharge following major abdominal surgery, with acceptable side effects.

Intraperitoneal aerosolization of bupivacaine reduces postoperative pain in laparoscopic surgery: a randomized prospective controlled double-blinded clinical trial

BACKGROUND

Laparoscopic strategies for managing intraabdominal pathologies offer significant benefits compared with conventional approaches. Of interest are reports of decreased postoperative pain, resulting in shorter hospitalization and earlier return to normal activity. However, many patients still require strong analgesia postoperatively. This study analyzed the use of intraoperatively delivered aerosolized intraperitoneal bupivacaine and its ability to reduce postoperative pain.

METHODS

For this study, 80 patients undergoing laparoscopic cholecystectomy were recruited and divided randomly into four groups: control (n = 20), aerosolized bupivacaine (n = 20), aerosolized normal saline (n = 20), and local bupivacaine in the bladder bed (n = 20). All the patients had standard preoperative, intraoperative, and postoperative care. Pain scores were recorded by the nursing staff in recovery, then 6, 12, and 24 h postoperatively using a standard 0 to 10 pain scoring scale. In addition, opiate consumption and oral analgesia were recorded.

RESULTS

Aerosolized bupivacaine significantly reduced postoperative pain in comparison with all other treatments (p < 0.05). Injection of bupivacaine into the gallbladder bed did not result in a significant difference from the control condition.

CONCLUSION

Aerosolized intraperitoneal local anesthetic is an effective method for controlling postoperative pain. It significantly helped to reduce opiate use and contributed to rapid mobilization, leading to short hospitalization and possible reduction in treatment cost.

Comparison of colonic stenting and open surgery for malignant large bowel obstruction

BACKGROUND

Colonic stents potentially offer effective palliation for those with bowel obstruction attributable to incurable malignancy, and a "bridge to surgery" for those in whom emergency surgery would necessitate a stoma. The current study compared the outcomes of stents and open surgery in the management of malignant large bowel obstruction.

METHODS

A literature search of the Medline, Ovid, Embase and Cochrane databases was performed to identify comparative studies reporting outcomes on colonic stenting and surgery for large bowel obstruction. Random effects meta-analytical techniques were applied to identify differences in outcomes between the two groups. Sensitivity analysis of high quality studies, those reporting on more than 35 patients, those solely concerning colorectal cancer and studies performing intention to treat analysis was undertaken to evaluate the study heterogeneity.

RESULTS

A total of 10 studies satisfied the criteria for inclusion, with outcomes reported for 451 patients. Stent insertion was attempted for 244 patients (54.1%), and proved successful for 226 (92.6%). The length of hospital stay was shorter by 7.72 days in the stent group (p < 0.001), which also had lower mortality (p = 0.03) and fewer medical complications (p < 0.001). Stoma formation at any point during management was significantly lower than in the stent group (odds ratio, 0.02; p < 0.001), and "bridging to surgery" did not adversely influence survival.

CONCLUSIONS

Colonic stenting offers effective palliation for malignant bowel obstruction, with short lengths of hospital stay and a low rate for stoma formation, but data on quality of life and economic evaluation are limited. There is no evidence of differences in long-term survival between those who have stents followed by subsequent resection and those undergoing emergency bowel resection.

A surgically induced hypoxic environment causes changes in the metastatic behaviour of tumours in vitro

The use of laparoscopic techniques for curative resections of malignant tumours has been under scrutiny. The potential benefits to the patient in the form of earlier recovery and less immune paresis are countered by the reports of increased tumour recurrence. The biological sequelae of the hypoxic laparoscopic environment on tumour cells is unknown. Components of the metastatic cascade were evaluated under in vitro laparoscopic conditions using a human colonic adenocarcinoma cell line (SW1222). Exposure to the laparoscopic gases carbon dioxide and helium for 4 h, comparable to the duration of a laparoscopic colorectal resection, had no effect on cell viability. A cellular hypoxic insult was demonstrated by the induction of hypoxia inducible factor 1alpha (HIF-1alpha). Exposure also resulted in significant reduction in homotypic adhesion as well as to a variety of extracellular matrix components. These effects were recoverable under re-oxygenation. The changes were reflected at the molecular level by significant down regulation of adhesion molecules known to be involved in tumour progression (E-cadherin, CD44 and beta1 sub-unit). Modulation of adherence has significant implications for laparoscopic oncological surgery, demonstrating that tumours become potentially more friable and easier to disseminate in surgeons who are less experienced or where instrumentation is sub-optimal.

Social deprivation and outcomes in colorectal cancer

Background

The aim of this study was to examine the influence of social deprivation on postoperative mortality and length of stay in patients having surgery for colorectal cancer.

Methods

Data were extracted from the Association of Coloproctology of Great Britain and Ireland database of patients presenting between April 2001 and March 2002. The effect of social deprivation, measured by the Townsend score, on 30-day postoperative mortality and length of stay was evaluated by two-level hierarchical regression analysis.

Results

A total of 7290 (86·8 per cent) patients underwent surgery. Operative mortality was 6·7 per cent and median length of stay 11 days. Deprivation indices were significantly higher in patients with Dukes' ‘D’ cancers, undergoing emergency surgery and with higher American Society of Anesthesiologists (ASA) grades (P &lt; 0·005). Worsening deprivation was associated with higher operative mortality and longer stay (P = 0·014). For each unit increase in deprivation, there was 2·9 (95 per cent confidence interval 0·5 to 5·2) per cent increase in 30-day mortality. On multifactorial analysis, social deprivation was an independent predictor of length of stay, but its effect on operative mortality was explained by differences in ASA grade, operative urgency and Dukes' classification.

Conclusion

Social deprivation was an independent risk factor of postoperative length of stay and associated with higher postoperative mortality. These results have important implications for risk modelling of postoperative outcomes.

Laparoscopic vs open subtotal colectomy for benign and malignant disease

AIM

The present meta-analysis aims to compare short-term and long-term outcomes in patients undergoing laparoscopic or open subtotal colectomy for benign and malignant disease.

METHODS

A literature search of Medline, Ovid, Embase and Cochrane databases was performed to identify studies published between 1992 and 2005, comparing laparoscopic (LSC) and open (OSC) subtotal colectomy. A random effect meta-analytical technique was used and sensitivity analysis performed on studies published since the beginning of 2000, higher quality papers, those reporting on more than 40 patients, and those studies reporting on adult cases or acute colitis.

RESULTS

A total of eight studies satisfied the criteria for inclusion. These included outcomes on 336 patients, 143 (42.6%) of whom had undergone laparoscopic resection, with an overall conversion rate to open surgery of 5% (range 0-11.8%). Operative time was significantly longer in the laparoscopic group by 86.2 min (P < 0.001) and throughout subgroup analysis, although it was only in patients with acute colitis that this finding was without significant heterogeneity. Operative blood loss was less in the laparoscopic group by 57.5 millilitres in high quality and studies published since 2000, and 65.3 millilitres in those reporting on more than 40 patients. There was no significant difference in early or long-term complications between the groups. A statistically significant reduction in length of postoperative stay was observed in the laparoscopic groups by 2.9 days (P < 0.001).

CONCLUSION

Laparoscopic subtotal colectomy was associated with longer operating times but a reduced length of stay compared to open surgery. Although short-term outcomes were equivalent in both groups, the suggested benefits in terms of reduced long-term obstructive complications were not supported by this meta-analysis.

Comparison of laparoscopic and open ileocecal resection for Crohn's disease: a metaanalysis

BACKGROUND

The role of laparoscopic surgery for patients with ileocecal Crohn's disease is a contentious issue. This metaanalysis aimed to compare open resection with laparoscopically assisted resection for ileocecal Crohn's disease.

METHODS

A literature search of the Medline, Ovid, Embase, and Cochrane databases was performed to identify comparative studies reporting outcomes for both laparoscopic and open ileocecal resection. Metaanalytical techniques were applied to identify differences in outcomes between the two groups. Sensitivity analysis was undertaken to evaluate the heterogeneity of the study.

RESULTS

Of 20 studies identified by literature review, 15 satisfied the criteria for inclusion in the study. These included outcomes for 783 patients, 338 (43.2%) of whom had undergone laparoscopic resection, with an overall conversion rate to open surgery of 6.8%. The operative time was significantly longer in the laparoscopic group, by 29.6 min (p = 0.002), although the blood loss and complications in the two groups were similar. In terms of postoperative recovery, the laparoscopic patients had a significantly shorter time for recovery of their enteric function and a shorter hospital stay, by 2.7 days (p < 0.001).

CONCLUSIONS

For selected patients with noncomplicated ileocecal Crohn's disease, laparoscopic resection offered substantial advantages in terms of more rapid resolution of postoperative ileus and shortened hospital stay. There was no increase in complications, as compared with open surgery. The contraindications to laparoscopic approaches for Crohn's disease remain undefined.

Meta-analysis of observational studies of ileorectal versus ileal pouch-anal anastomosis for familial adenomatous polyposis

BACKGROUND

Surgery for familial adenomatous polyposis (FAP) aims to minimize cancer risk while providing good functional outcome. Colectomy with ileorectal anastomosis and proctocolectomy with ileal pouch-anal anastomosis both offer this, but there is no clear consensus about which is better.

METHODS

This is a meta-analysis of comparative studies published between 1991 and 2003 reporting early and late postoperative adverse events, functional outcomes and quality of life.

RESULTS

Twelve studies containing 1002 patients (53.4 per cent ileal pouch, 46.6 per cent ileorectal anastomosis) were identified. Bowel frequency (weighted mean difference 1.62 (95 per cent confidence interval (c.i.) 1.05 to 2.20)), night defaecation (odds ratio (OR) 6.64 (95 per cent c.i. 2.99 to 14.74)) and use of incontinence pads (OR 2.72 (95 per cent c.i. 1.02 to 7.23)) were significantly less in the ileorectal group, although faecal urgency was reduced with the ileal pouch (odds ratio 0.43 (95 per cent c.i. 0.23 to 0.80)). Reoperation within 30 days was more common after ileal pouch construction (23.4 versus 11.6 per cent; OR 2.11 (95 per cent c.i. 1.21 to 3.70)). There was no significant difference between the techniques in terms of sexual dysfunction, dietary restriction, or postoperative complications. Rectal cancer was a diagnosis only in the ileorectal group (5.5 per cent).

CONCLUSION

Ileal pouch and ileorectal anastomoses have individual merits. Further research is needed to determine which most benefits patients with FAP.

Treatment of poisoning induced cardiac impairment using cardiopulmonary bypass: a review

Severe poisoning can cause potentially fatal cardiac depression. Cardiopulmonary bypass (CPB) can support the depressed myocardium, but there are no clear indications or guidelines available on its use in severe poisoning. A review was conducted of relevant papers in the available literature (seven single case reports of both deliberate and accidental ingestion of cardiotoxic drugs and two animal studies). Although CPB is rarely used in the management of poisoning, it may have potential benefits for haemodynamic instability not responding to conventional measures. At present there is insufficient evidence concerning the use of CPB as a treatment for severe cardiac impairment due to poisoning (grade C). This review suggests that in patients with severe and potentially prolonged reversible cardiotoxicity there is potential for full survival with CPB, provided that the patient has not already sustained hypoxic cerebral damage due to resistant hypotension prior to its use.

A comparison of segmental vs subtotal/total colectomy for colonic Crohn's disease: a meta-analysis

OBJECTIVE

Using meta-analytical techniques the present study evaluated differences in short-term and long-term outcomes of adult patients with colonic Crohn's disease who underwent either colectomy with ileorectal anastomosis (IRA) or segmental colectomy (SC).

METHODS

Comparative studies published between 1988 and 2002, of subtotal/total colectomy and ileorectal anastomosis vs segmental colectomy, were used. The study end points included were surgical and overall recurrence, time to recurrence, postoperative morbidity and incidence of permanent stoma. Random and fixed-effect meta-analytical models were used to evaluate the study outcomes. Sensitivity analysis, funnel plot and meta-regressive techniques were carried out to explain the heterogeneity and selection bias between the studies.

RESULTS

Six studies, consisting of a total of 488 patients (223 IRA and 265 SC) were included. Analysis of the data suggested that there was no significant difference between IRA and SC in recurrence of Crohn's disease. Time to recurrence was longer in the IRA group by 4.4 years (95% CI: 3.1-5.8), P < 0.001. There was no difference between the incidence of postoperative complications (OR = 1.4., 95% CI 0.16-12.74) or the need for a permanent stoma between the two groups (OR = 2.75, 95% CI 0.78-9.71). Patients with two or more colonic segments involved were associated with lower re-operation rate in the IRA group, a difference which did not reach statistical significance (P = 0.177).

CONCLUSIONS

Both procedures were equally effective as treatment options for colonic Crohn's disease however, patients in the SC group exhibited recurrence earlier than those in the IRA group. The choice of operation is dependent on the extent of colonic disease, with a trend towards better outcomes with IRA for two or more colonic segments involved. Since no prospective randomised study has been undertaken, a clear view about which approach is more suitable for localised colonic Crohn's disease cannot be obtained.

Self-appraisal hierarchical task analysis of laparoscopic surgery performed by expert surgeons

BACKGROUND

Evaluation of technical skill is notoriously difficult because of the subjectivity and time-consuming expert analysis. No ongoing evaluation scheme exists to assess the continuing competency of surgeons. This study examined whether surgeons' self-assessment accurately reflects their actual surgical technique.

METHODS

Hierarchical task analysis (HTA) of laparoscopic cholecystectomy was constructed. Ten expert surgeons were asked to modify the HTA for their own technique. The HTAs of these surgeons then were compared with their actual operations, which had been recorded and assessed by two observers.

RESULTS

A total of 40 operations were assessed. All the gallbladders subjected to surgery were classified as grades 1 to 3. The mean interrater reliability for the two observers had a k value of 0.84 (p < 0.05), and the mean intrarater reliability between surgeons and observers had a k value of 0.79 (p < 0.05).

CONCLUSIONS

Surgeons' self-evaluation is accurate for technical skills aspects of their operations. This study demonstrates that self-appraisal using HTA is feasible, accurate, and practical. The authors aim to increase the numbers in their study and also to recruit residents.

Robotic prostatectomy: the first UK experience

BACKGROUND

We describe a teamwork approach to setting up the UK's first clinical programme for robotically assisted laparoscopic radical prostatectomy.

METHODS

On 22 November 2004 the Imperial Robotic Urological Surgery Group performed their first robotically assisted prostatectomy. Robotically assisted prostatectomy lends itself to division into eight definable stages. A team of four consultant urological surgeons utilized a structured rotating system, using these stages, for time at the console and tableside assisting. Fluidity of surgery was maintained by a surgeon acting as the tableside assistant for the stage prior to moving to the console. Data was collected prospectively for the first 50 cases and parameters associated with the learning curve compared to other reported series.

RESULTS

Median operative time of 369.5 mins, median blood loss of 700 ml, with 12% of patients requiring a blood transfusion. Four patients required conversion to an open procedure; one resulting from equipment failure and three due to failure of progression. Four patients had an anastomotic leak with resulting ileus and two patients sustained rectal injuries, which were repaired intraoperatively using the robot. Median hospital stay was 4 days with a 22% positive surgical margin rate.

CONCLUSION

Parameters indicative of the learning curve are comparable to existing published initial series of other robotic centres. The use of teamwork has enabled us to provide safe and time-efficient training for four surgeons simultaneously. The structured approach used in this setting demonstrates that urological surgeons of varying laparoscopic experience can acquire the skills necessary to competently perform laparoscopic radical prostatectomy.

Magnetic resonance colonography versus colonoscopy as a diagnostic investigation for colorectal cancer: a meta-analysis

AIMS

Magnetic resonance colonography (MRC) is emerging as a potential complementary investigation for the diagnosis of colorectal cancer (CRC) and also for benign pathology such as diverticular disease. A meta-analysis reporting the use of MRC is yet to be performed. The aim of this study was to evaluate the diagnostic accuracy of MRC compared with the gold-standard investigation, conventional colonoscopy (CC).

METHODS

A literature search was carried out to identify studies containing comparative data between MRC findings and CC findings. Quantitative meta-analysis for diagnostic tests was performed, which included the calculation of independent sensitivities, specificities, diagnostic odds ratios, the construction of summary receiver operating characteristic (SROC) curves, pooled analysis and sensitivity analysis. The study heterogeneity was evaluated by the Q-test using a random-effect model to accommodate the cluster of outcomes between individual studies.

RESULTS

In all, 8 comparative studies were identified, involving 563 patients. The calculated pooled sensitivity for all lesions was 75% (95% CI: 47% to 91%), the specificity was 96% (95% CI: 86% to 98%) and the area under the ROC curve was 90% (weighted). On sensitivity analysis, MRC had a better diagnostic accuracy for CRC than for polyps, with a sensitivity of 91% (95% CI: 97% to 91%), a specificity of 98% (95% CI: 66% to 99%) and an area under the ROC curve of 92%. There was no significant heterogeneity between the studies with regard to the diagnostic accuracy of MRC for CRC.

CONCLUSION

This meta-analysis suggests that MRC is an imaging technique with high discrimination for cases presenting with colorectal cancer. The exact diagnostic role of MRC needs to be clarified (e.g. suitable for an elderly person with suspected CRC). Further evaluation is necessary to refine its applicability and diagnostic accuracy in comparison with other imaging methods such as computed tomography colonography.

Laparoscopic environmental changes during surgery enhance the invasive potential of tumours

OBJECTIVE

The use of laparoscopic techniques in resection of malignant tumours has been proposed to offer potential benefit to the patient in the form of earlier recovery and less immune paresis; however, reported tumour seeding, both peritoneal and at port site, has put this approach into question. The biological effects of the introduction of carbon dioxide or helium to form a pneumoperitoneum on tumour invasion and dissemination are unknown.

METHODS

A human colonic adenocarcinoma cell line (SW1222) was exposed to in vitro laparoscopic environment of either carbon dioxide or helium for 4 h, mimicking the duration of a laparoscopic colorectal resection. Alteration in production of matrix metalloproteinase (MMP)-2, MMP-9 and urokinase-type plasminogen activator (uPA) due to exposure to a laparoscopic environment was determined by zymography and correlated to invasive capacity by a standard Matrigel-based invasion assay. Incorporation of specific gelatinase inhibitors or antibodies directed at the uPA receptor was utilized to determine the relative importance of proteases.

RESULTS

Exposure to the laparoscopic environment significantly enhanced production of the proteases MMP-2, MMP-9 and uPA. A concomitant enhancement of invasive capacity was also observed, being blocked by specific protease inhibitors. Changes in both protease production and aggression were observable for at least 24 h following the removal of the operative environment, indicating the possible long-term effects of the initial insult.

CONCLUSION

Exposure to the laparoscopic environment enhances the invasive capacity of colonic adenocarcinomas via a well-defined protease-determined pathway. It therefore appears likely that tumour cells released into the operative field can be made increasingly aggressive by a laparoscopic operative environment and can thus contribute to disease dissemination.

Peritoneal nebulizer: a novel technique for delivering intraperitoneal therapeutics in laparoscopic surgery to prevent locoregional recurrence

BACKGROUND

Peritoneal involvement is a significant issue in the treatment of gastrointestinal malignancies. Current statistics indicate that after surgical intervention, up to 20% of patients will present with locoregional metastasis. The ability to inhibit initial tumor adhesion to the mesothelial lining of the peritoneum may be considered critical in the inhibition of tumor development. This article describes, the use of a novel nebulizer system capable of delivering high-concentration, low-dose therapeutics to the peritoneal cavity.

METHODS

For this study, 30 male WAG rats were inoculated with CC531 colorectal tumor cells. The rats were randomized into three groups: control group (n = 10), heparin-treated group (n = 10), and high-molecular-weight hyaluronan-treated group (n = 10). A peritoneal cancer index was used to determine tumor burden at 15 days. Analysis of variance (ANOVA) was used to compare multiple group means.

RESULTS

Nebulization therapy was performed without any complication in the cohort. Heparin inhibited macroscopic intraperitoneal tumor growth completely (p = 0.0001) without affecting tumor cell viability. The introduction of hyaluronan attenuated both tumor size and distribution, was compared with the control group (p = 0.002).

CONCLUSION

Nebulized heparin and hyaluronic acid using a novel nebulization technique attenuates peritoneal tumor growth after laparoscopic surgery. The technique itself is easy to use and safe.

Technical skills errors in laparoscopic cholecystectomy by expert surgeons

BACKGROUND

Performing laparoscopic surgery involves a complex cascade of cognitive skills, which may inherently have a constant technical error rate. We assess generic and specific minor and major error rates in laparoscopic cholecystectomies (LCs) performed by consultant surgeons.

METHODS

Checklists of generic (11) and specific technical minor (six) and major events (eight) were devised for LCs. Two experienced surgeons assessed each full-length operation blindly and independently.

RESULTS

A total of 37 LCs were performed by eight consultants. There were no major intraoperative or postoperative complications. Mean inter-rater reliability was kappa = 0.91 (range 0.80-0.98) for each of the error categories. Error rates were generic (27/407) 6.6%, minor (59/222) 26.6%, and major (8/296) 2.7%, respectively. There was a significant statistical difference between the minor error group and the other groups, p <or= 0.05.

CONCLUSIONS

Performing laparoscopic surgery may always have a background technical error rate. Our present study demonstrates a migration of surgical technical errors in expert laparoscopic surgeons. The surgeons migrate technically when they execute a high rate of procedure-specific minor errors. However, when it comes to the major fundamental aspects of the operation, they dynamically adapt and migrate away from performing major technical errors. We aim to continue the study to increase cases, assess trainees as well, and also explore other factors that may affect the surgeon when executing surgical technical tasks.

Attitudes towards skills examinations for basic surgical trainees

Objective measures of surgical skill and cognition are becoming available. A questionnaire study examining surgeons' beliefs towards a skills-based examination, current standards and possible benefits was devised. Three hundred pairs of standardised anonymous questionnaires were sent to consultants and their basic surgical trainees (BSTs) irrespective of surgical specialty. Responses were requested using a Likert scale (1-5, 3=neutral response). Two-hundred and two replies were received (including 54 pairs). BST experience ranged from 6 to 60 months (mean 24 months). When questioned regarding current training in basic surgical skills, only 34% believed that they were given adequate training at present. Sixty-four per cent of respondents believed the introduction of a skills examination would raise standards and 66% believed it necessary. Eighty-three per cent of respondents believed that they or their BST would practice these skills, if an examination were introduced and 85% wanted or would provide dedicated teaching time for this. However, 68% had no access to a dedicated skills facility, and uptake of these, where available, was variable. When questioned about their ability to perform the six appropriate tasks, there was a poor correlation of scoring between the groups. Consultants and their BSTs do not believe that they are given adequate training in basic skills. The introduction of an examination would lead to practice of these skills and is seen as a positive move.

Perioperative diagnosis of cystosarcoma phyllodes of the breast may be enhanced by MIB-1 index

BACKGROUND

The recurring theme in cystosarcoma phyllodes (CSP) is one of underdiagnosis by pathologists and undertreatment by surgeons. Major areas of investigation relating to the diagnosis of CSP center on accurate preoperative diagnosis, elucidating the relevance of histological classification with respect to outcome, and identifying novel markers to reliably differentiate CSP from fibroadenoma (FA).

MATERIALS AND METHODS

Fifteen CSP and 7 cellular FA controls (where the preoperative diagnosis was unclear) were retrospectively investigated. Preoperative histological and radiological investigations were reviewed for efficacy. The ability of MIB-1 antibody to differentiate the two fibroepithelial lesions was investigated using immunohistochemical estimation of the MIB-1 index.

RESULTS AND DISCUSSION

Preoperative core biopsy had a sensitivity of 75% but was carried out in only 23% of cases. Fine needle aspiration cytology and radiological assessment were not efficacious in preoperative diagnosis. Proliferative activity (MIB-1 indices) was significantly higher in CSP than in a selected population of FA where there was preoperative diagnostic uncertainty (P < 0.0001). Indices were also able to determine CSP subclassification. This suggests MIB-1 as a constructive adjunctive investigation when evaluating histological features to differentiate CSP from FA in difficult cases.

CONCLUSIONS

The use of MIB-1 may increase the sensitivity of preoperative core biopsy diagnosis, offering more effective surgical planning and decreasing immediate reoperation rates.

The Relationship Between Plasma MMP-1, -7, -8 and -13 Levels and Embolic Potential During Carotid Endoluminal Intervention

BACKGROUND

Patients undergoing carotid endoluminal intervention are at risk of embolic stroke even with the use of distal protection devices. Matrix metalloproteinases (MMPs) have been implicated as a causal factor in plaque instability leading to spontaneous embolisation. We investigated whether plasma MMP levels correlated with the embolisation during carotid endoluminal intervention.

METHODS

Thirty circumferentially intact carotid endarterectomy specimens were subjected to a standardised angioplasty procedure in a pulsatile ex vivo model. Emboli collected in a series of distal filters were counted and sized. Plasma samples were collected pre-operatively and analysed for MMP-7 and MMP-8 levels using Western immunoblotting. MMP-1 and MMP-13 levels were determined using ELISA. Emboli number and maximum size were correlated with plasma levels of the MMPs using Spearmans rank.

RESULTS

Total MMP-8 levels were related to maximum embolus size (r=0.442, p=0.005) but not emboli number (r=0.342, p=0.052). MMP-1, -7 and -13 were not correlated with either emboli number or with maximum embolus size.

CONCLUSION

Pre-operative plasma MMP-8 levels are related to the size of emboli from plaques during carotid endovascular intervention. Further in vivo studies need to be performed to assess the importance of this finding. There is potential for development of plasma markers to identify those patients at greater risk of embolic stroke during carotid endoluminal intervention.

Laparoscopic enhancement of tumour cell binding to the peritoneum is inhibited by anti-intercellular adhesion molecule-1 monoclonal antibody

BACKGROUND

There still remain some concerns over the phenomenon of port-site metastases (PSM) after laparoscopic surgery. The aim of this study was to investigate the effect of the pneumoperitoneum on tumor-mesothelial cell interactions.

METHODS

The adhesion of a colon carcinoma cell line to a mesothelial cell monolayer exposed to carbon dioxide, helium, or air was assessed using an in vitro adhesion assay. Changes in adherence were correlated with alterations in cell surface molecule expression by the mesothelial cells using flow cytometry after exposure to the different environments.

RESULTS

Exposure of the mesothelial cells to an in vitro pneumoperitoneum significantly enhanced tumor cell binding to the mesothelial cell monolayer. No differences in cell viability were observed between the groups. This was associated with increased expression of mesothelial intercellular adhesion molecule-1 (ICAM-1) mediated by nuclear factor kappa-B. The enhanced adhesion was abolished by ICAM-1 inhibition.

CONCLUSIONS

This study demonstrated that the laparoscopic environment increases the susceptibility of the mesothelium to tumor cell adherence, and this may be explained by changes in ICAM-1 expression.

Tele-manipulator robots in surgery

Future promise, but expensive

Pneumoperitoneum augmented tumor invasiveness is abolished by matrix metalloproteinase blockade

BACKGROUND

Certain surgical strategies, including Helium (He) and carbon dioxide (CO2) insufflation in laparoscopy, have been shown to induce a hypoxic environment. This may have a significant effect on the invasive capacity of tumor cells and may be a factor in the incidence of port-site metastases seen in patients following laparoscopic resection for malignancy.

METHODS

A colon adenocarcinoma cell line (SW1222) was exposed to an in vitro pneumoperitoneum of CO2 or He at 3 mmHg or left in normal growth conditions (control). After a 4-hour exposure to an in vitro pneumoperitoneum, the ability of the cells to invade through 8.0-microm Transwell filters coated with Matrigel was analyzed by colorimetric MTS assay and by direct staining of the filters. The effect of the addition of a known blocker of matrix metalloproteinases (MMPs), 1,10-phenanthroline (1,10-P), was investigated.

RESULTS

Cells exposed to an in vitro pneumoperitoneum demonstrate significantly increased invasive capacity compared to the control set, without loss of viability (He vs control, p <0.001; CO2 vs control, p <0.001). This augmented capacity is abolished by the addition of 1,10-P (p <0.01).

CONCLUSION

Exposure of a colonic adenocarcinoma cell line to either a CO2 or He pneumoperitoneum causes an increase in tumor cell invasiveness, which is abolished by the presence of a known inhibitor of MMPs. This suggests that MMPs have an important role in the metastatic potential of tumors exposed to a hypoxic operative environment.

Cause and prevention of electrosurgical injuries in laparoscopy

BACKGROUND

Electrosurgical injuries occur during laparoscopic operations and are potentially serious. The overall incidence of recognized injuries is between one and two patients per 1,000 operations. The majority go unrecognized at the time of the electrical insult and commonly present three to seven days afterward with fever and pain in the abdomen. Since these injuries appear late the pathophysiology remains speculative.

STUDY DESIGN

This article reviewed the physics of electrosurgery and provides the surgeon with an insight to the mechanisms responsible in each type of injury. In addition, a comprehensive search of the world literature has reviewed all articles on the topic.

RESULTS

The main causes of electrosurgical injuries are: inadvertent touching or grasping of tissue during current application, direct coupling between a portion of intestine and a metal probe that is touching the activated probe, insulation breaks in the electrodes, direct sparking to the intestine from the diathermy probe, and current passage to the intestine from recently coagulated, electrically isolated tissue. The majority of injuries, not surprisingly, are caused by monopolar diathermy. Bipolar diathermy is safer and should be used in preference to monopolar diathermy, especially in anatomically crowded areas.

CONCLUSIONS

An awareness of the hazards of diathermy together with an understanding of the mechanisms of injury should enable the surgeon to dissect tissue and to achieve hemostasis, while at the same time decreasing the risk of serious complications to the patient.

A safe new procedure for high-risk patients with symptomatic gallstones

Cholecystectomy is associated with an appreciable mortality rate in elderly high-risk patients. Patients aged over 60 years with symptomatic gallstones, at high operative risk, underwent cholecystotomy under local anaesthesia through a 3-cm incision. Stones were removed and clearance was demonstrated endoscopically and by tube cholecystography. Catheter drainage was continued for 7 days until a further cholecystogram confirmed clearance. The procedure was attempted in 26 patients with concomitant cardiovascular, respiratory or malignant disease. Successful removal of all gallbladder stones was possible in 24 patients. Four patients had common bile duct stones demonstrated on cholecystography, all of which were successfully treated by endoscopic sphincterotomy. All patients are symptom-free at a mean follow-up of 36 weeks with no recurrent stones on ultrasonography.