Requirement for bowel preparation in colorectal surgery

Incidence of Anastomotic Leak in Patients Undergoing Elective Colon Resection without Mechanical Bowel Preparation: Our Updated Experience and Two-year Review

Mechanical bowel preparation before elective colon resection has recently been questioned in the literature. We report a prospective study evaluating the anastomotic leak rate in patients undergoing elective colorectal surgery without preoperative mechanical bowel preparation. One hundred fifty-three patients undergoing elective colon resection from July 2006 to June 2008 were enrolled into this Institutional Review Board-approved study. All patients were operated on by a single surgeon at a single institution. No patients received mechanical bowel preparation. Of the 153 patients enrolled, 51.6 per cent had a colorectostomy, 32 per cent had an ileocolostomy, 10.4 per cent had a colocolostomy 5.2 per cent had an ileoanal anastomosis, and 0.6 per cent had an ileorectostomy performed. A total of eight patients (5.2%) developed an anastomotic leak. Of these patients, four required reoperation, three were managed with percutaneous drainage, and one was managed with antibiotics alone. Five of the eight patients who developed an anastomotic leak had significant preoperative comorbidities, including neoadjuvant radiation therapy, diabetes mellitus, end-stage renal disease, prior anastomotic leak, and tobacco use. Elective colon resection can be performed safely without preoperative mechanical bowel preparation. Vigilance for anastomotic leak must be maintained at all times, especially in patients with comorbidities that predispose to anastomotic leak.

Is there a current role for preoperative non-absorbable oral antimicrobial agents for prophylaxis of infection after colorectal surgery?

BACKGROUND

In numerous scientific studies, oral antibiotic bowel preparation has reduced surgical site infections in patients undergoing colorectal surgery. The historical evolution of antibiotic bowel preparation is presented with a review of the scientific basis of its effectiveness.

METHODS

Review of the pertinent English language literature.

RESULTS

Successful oral antibiotic bowel preparation requires effective mechanical preparation. The progressive shift of preoperative preparation to the outpatient setting has led to a reduction in the use of oral antibiotics. Such preparation, however, continues to be effective although in current surgical practice is often augmented with perioperative, parenteral antimicrobials.

CONCLUSION

Oral antibiotic bowel preparation has a role in the prevention of surgical site infection in the patient undergoing colorectal surgery.

Treatment of left-sided colonic emergencies: a comparison of US and UK surgical practices

BACKGROUND

Surgeons are increasingly considering resection and primary anastomosis when treating left-sided colonic obstruction or perforation in preference to the more traditional staged procedures. Previous studies in the United Kingdom (UK) and United States of America (USA) have suggested a greater interest in single-staged procedures amongst UK surgeons. This study was aimed to directly compare the treatment preferences between UK and US surgeons.

METHOD

A questionnaire, designed to determine the procedure of choice when faced with left-sided colonic emergencies in patients with good and poor anaesthetic risk, was sent to 500 surgeons in the UK and 500 surgeons in the USA.

RESULTS

UK surgeons were more likely to perform resection, primary anastomosis and on-table colonic lavage in patients with sigmoid obstruction (good anaesthetic risk: P < 0.0001; poor risk: P < 0.01) and sigmoid perforation (good risk: P < 0.0001). In good-risk patients with sigmoid obstruction, US surgeons were more likely than UK to choose Hartmann's procedure (P < 0.0001). US surgeons performing primary anastomosis were less likely to perform on-table lavage.

CONCLUSION

Single-stage procedures are widely accepted as viable treatment options in both the UK and the USA when dealing with left-sided colonic emergencies. British surgeons are more likely to favour single-staged procedures, particularly with on-table colonic lavage, when compared with US surgeons.

Treatment of left-sided colonic emergencies: a comparison of US, UK and Australian surgeons

BACKGROUND

This study sought to identify and compare the current practice of surgeons in Australia, the UK and the US when presented with a left-sided colonic emergency.

METHODS

Questionnaires were posted to 500 US, 500 UK and 500 Australian surgeons. Demographic data were collected regarding the surgeon's age and surgical interest, as well as their preferred method of managing left-sided colonic emergencies (namely obstruction and perforation in stable and unstable patients). The results were analysed using the chi-squared test.

RESULTS

Completed questionnaires were received from 224 UK surgeons (45%), 180 US surgeons (36%) and 259 Australian surgeons (52%). All the US surgeons had an interest in gastrointestinal surgery, while 31% of the UK surgeons and 22% of Australian surgeons had an interest in colorectal surgery. In a haemodynamically stable patient with a good anaesthetic risk presenting with a complete sigmoid obstruction, significantly more UK (84%) and Australian surgeons (70%) would perform a resection and anastomosis than US surgeons (54%, p<0.0001). Of those with a colorectal interest, 97% of UK surgeons and 80% of Australian surgeons would opt for resection and anastomosis. In a haemodynamically stable patient with a good anaesthetic risk with a perforation of the sigmoid colon and purulent peritonitis, 46% of UK surgeons, 32% of Australian surgeons and 33% of US surgeons would opt for resection and anastomosis, and among colorectal surgeons, 68% of UK surgeons and 50% of Australian surgeons would opt for resection and anastomosis.

CONCLUSIONS

The management of left-sided colonic emergencies varies depending on geographic location and degree of colorectal subspecialization. While the literature suggests that single-stage procedures are accepted and safe, the reasons for this variation are explored.

Updated systematic review and meta-analysis of randomized clinical trials on the role of mechanical bowel preparation before colorectal surgery

BACKGROUND

Earlier meta-analyses of small randomized trials suggested that mechanical bowel preparation (MBP) should be omitted before colorectal surgery because it does not affect complication rates 0 mortality and may be even harmful; however, more recent large randomized trials suggested an increased occurrence of pelvic abscesses in the absence of MBP. Therefore, an updated large meta-analysis was conducted to re-evaluate the role of MBP in colorectal surgery. Furthermore, the influence of different kind of MBP regimes on infectious outcomes was examined.

METHODS

The meta-analysis was conducted according to the QUOROM statement; the inclusion criteria were randomized clinical trials comparing MBP with no MBP before colorectal surgery. The primary outcome was anastomotic leakage; secondary outcomes were other septic complications.

RESULTS

Fourteen trials were included with a total number of 4859 patients: 2452 in the MBP group and 2407 in the no MBP group. We found no statistical difference between the groups for anastomotic leakage [OR = 1.12 (0.82-1.53), P = 0.46], pelvic or abdominal abscess (P = 0.75), and wound sepsis (P = 0.11). When all surgical site infections were considered, the meta-analysis favored no MBP [OR = 1.40 (1.05-1.87), P = 0.02].Sensitivity analyses showed similar results for all subgroups but when poor or small trials were excluded, there was a slightly higher risk of deep abdominal abscesses with no MBP, however, the number needed to harm was as high as 333 patients, suggesting this difference to be not clinically relevant. The use of different MBP regimes did not influence primary and secondary outcomes. The main limitation concerned rectal surgery for which the limited data preclude any interpretation.

CONCLUSION

Although it did not confirm the harmful effect of mechanical bowel preparation (suggested by previous meta-analyses), this meta-analysis including almost 5000 patients, demonstrates with a high level of evidence that any kind of mechanical bowel preparation should be omitted before colonic surgery.

Mechanical bowel preparation for elective colorectal surgery

BACKGROUND

The presence of bowel contents during surgery has been related to anastomotic leakage, but the belief that mechanical bowel preparation (MBP) is an efficient agent against leakage and infectious complications is based on observational data and expert opinions only.

OBJECTIVES

To determine the security and effectiveness of MBP on morbidity and mortality in colorectal surgery.

SEARCH STRATEGY

Publications describing trials of MBP before elective colorectal surgery were sought through searches of MEDLINE, EMBASE, LILACS, and The Cochrane Library; by handsearching relevant medical journals and conference proceedings, and through personal communication with colleagues.Searches were performed March 13, 2008.

SELECTION CRITERIA

Randomised controlled trials (RCTs) including participants submitted for elective colorectal surgery. Eligible interventions included any type of MBP compared with no MBP. Primary outcomes included anastomosis leakage - both rectal and colonic - and combined figures. Secondary outcomes included mortality, peritonitis, reoperation, wound infection, extra-abdominal complications, and overall surgical site infections.

DATA COLLECTION AND ANALYSIS

Data were independently extracted and checked. The methodological quality of each trial was assessed. Details of randomisation, blinding, type of analysis, and number lost to follow up were recorded. For analysis, the Peto-Odds Ratio (OR) was used as the default (no statistical heterogeneity was observed).

MAIN RESULTS

Four new trials were included at this update (total 13 RCTs with 4777 participants; 2390 allocated to MBP (Group A), and 2387 to no preparation (Group B), before elective colorectal surgery) .Anastomotic leakage occurred:(i) in 10.0% (14/139) of Group A, compared with 6.6% (9/136) of Group B for low anterior resection; Peto OR 1.73 (95% confidence interval (CI): 0.73 to 4.10).(ii) in 2.9% (32/1226) of Group A, compared with 2.5% (31/1228) of Group B for colonic surgery; Peto OR 1.13 (95% CI: 0.69 to 1.85). Overall anastomotic leakage occurred in 4.2% (102/2398) of Group A, compared with 3.4% (82/2378) of Group B; Peto OR 1.26 (95% CI: 0.941 to 1.69). Wound infection occurred in 9.6% (232/2417) of Group A, compared with 8.3% (200/2404) of Group B; Peto OR 1.19 (95% CI: 0.98 to 1.45). Sensitivity analyses did not produce any differences in overall results.

AUTHORS' CONCLUSIONS

There is no statistically significant evidence that patients benefit from MBP. The belief that MBP is necessary before elective colorectal surgery should be reconsidered. Further research on patients submitted for elective colorectal surgery in whom bowel continuity is restored, with stratification for colonic and rectal surgery, is still warranted.

Single-blinded randomized trial of mechanical bowel preparation for colon surgery with primary intraperitoneal anastomosis

INTRODUCTION

We report the final analysis of a prospective single-blinded randomized trial designed to investigate whether omission of preoperative mechanical bowel preparation increases the rate of surgical-site infection and anastomotic failure after elective colon surgery with intraperitoneal anastomosis by a single surgeon.

PATIENTS AND METHODS

Patients scheduled to undergo an elective colon or proximal rectal resection with a primary anastomosis by a single surgeon were randomized to receive either oral polyethylene glycol (Group A) or no mechanical bowel preparation (Group B). Patients were followed by an independent surgeon.

RESULTS

One hundred and forty nine patients were enrolled. Three patients (2%) were preoperatively excluded because of active immunosuppression and 13 (9%) were excluded from the final analysis. Of the remaining 129 patients, 65 were assigned to Group A and 64 to Group B. Thirty patients (23.2%) developed wound infection, (Group A = 24.6% and Group B = 17.2%; NS). There were three cases of intra-abdominal sepsis a (Group A 4.6%). The anastomotic failure rate was 5.4% (n = 7), four patients in Group A (6.2%) vs. three patients in Group B (4.7%) (NS). When SSI and anastomotic failure were combined, the complication rate in Group A was 35.4% vs. 21.9% for Group B. The NNH was 7.4.

CONCLUSION

Our final analysis shows that a single surgeon will not have a higher rate of either surgical-site infection or anastomotic failure if he/she routinely omits preoperative mechanical bowel preparation.

Mechanical bowel preparation for colorectal surgery: a meta-analysis on abdominal and systemic complications on almost 5,000 patients

BACKGROUND

Several studies concluded that mechanical bowel preparation (MBP) does not confer any advantage on reducing the anastomotic leak rate or wound infections. The aim of this meta-analysis was to review all prospective randomised controlled trials on the use of MBP before colorectal surgery in order to find differences in the rates of abdominal and systemic complications in view of recent published articles.

METHODS

Review of all randomised prospective trials compare MBP vs. non-MBP. Primary outcome measures were anastomotic leakages, abdomino-pelvic abscesses and postoperative ileus. Secondary outcomes were wound infections, extra-abdominal complications (urinary infections, pulmonary infections, deep venous thrombosis or pulmonary embolism, cardiac events), sepsis and mortality.

RESULTS

Twelve articles met the inclusion criteria with 4,919 patients. The non-MBP group showed no significant increase of the anastomotic leakages (3.4% vs. 4.1%; p = NS) and wound infections (8.7% vs. 9.6%; p = NS) but had a lower rate of postoperative cardiac events (2.5% vs. 4.0%; p = 0.04).

CONCLUSION

The evidence from recent studies, combined with previous ones, further suggests that the dogma of the necessity of mechanical bowel preparation before elective colorectal surgery should be reconsidered.

Mechanical bowel preparation in intestinal surgery: a meta-analysis and review of the literature

INTRODUCTION

Despite several meta-analyses and randomized controlled trials showing no benefit to patients, mechanical bowel preparation (MBP) remains the standard of practice for patients undergoing elective colorectal surgery.

METHODS

We performed a systematic review of the literature of trials that prospectively compared MBP with no MBP for patients undergoing elective colorectal resection. We searched MEDLINE, LILACS, and SCISEARCH, abstracts of pertinent scientific meetings and reference lists for each article found. Experts in the field were queried as to knowledge of additional reports. Outcomes abstracted were anastomotic leaks and wound infections. Meta-analysis was performed using Peto Odds ratio.

RESULTS

Of 4,601 patients (13 trials), 2,304 received MBP (Group 1) and 2,297 did not (Group 2). Anastomotic leaks occurred in 97(4.2%) patients in Group 1 and in 81(3.5%) patients in Group 2 (Peto OR = 1.214, CI 95%:0.899-1.64, P = 0.206). Wound infections occurred in 227(9.9%) patients in Group 1 and in 201(8.8%) patients in Group 2 (Peto OR = 1.156, CI 95%:0.946-1.413, P = 0.155).

DISCUSSION

This meta-analysis demonstrates that MBP provides no benefit to patients undergoing elective colorectal surgery, thus, supporting elimination of routine MBP in elective colorectal surgery.

CONCLUSION

In conclusion, MBP is of no benefit to patients undergoing elective colorectal resection and need not be recommended to meet "standard of care."

Oral colorectal cleansing preparations in adults

Bowel preparation has been a much-debated issue for both colonoscopy and for colorectal surgery. While bowel preparation for colonoscopy is clearly mandatory for optimal intraluminal visualization, bowel preparation for surgery has recently been challenged. This review evaluates oral bowel preparation, based on evidence in the literature, in order to provide a practical guide for physicians and practitioners about oral bowel cleansing preparations in current use for both colonoscopy and for colorectal surgery.A MEDLINE search, limited to publications in English language, was done through Ovid including articles published from 1966 to 2007 about bowel preparation using terms 'pre-operative care' and 'colonoscopy' or 'surgical procedure' associated with 'polyethylene glycol' and 'sodium phosphate'. The references lists from the identified articles were also included in the review. No bowel preparation method meets the ideal criteria for bowel cleansing prior to colonoscopy. However, polyethylene glycol-electrolyte lavage solution (PEG-ELS) and sodium phosphate are the most commonly used bowel preparations before colonoscopy and colon surgery. Both preparations are safely used and effective; however, some precautions should be considered, particularly with sodium phosphate. In addition, the efficacy of low-volume PEG-ELS can be improved by the addition of preparation adjuncts. Timing and dose are important considerations regardless of the method used. Mechanical bowel preparation for surgery has been questioned, and shown to have no extra benefits and possibly the association with increased morbidity. Regardless of the evidence, there are many randomized controlled trials showing the lack of benefit of mechanical bowel preparation.

Mechanical bowel preparation for elective colorectal surgery: a multicentre randomised trial

BACKGROUND

Mechanical bowel preparation is a common practice before elective colorectal surgery. We aimed to compare the rate of anastomotic leakage after elective colorectal resections and primary anastomoses between patients who did or did not have mechanical bowel preparation.

METHODS

We did a multicentre randomised non-inferiority study at 13 hospitals. We randomly assigned 1431 patients who were going to have elective colorectal surgery to either receive mechanical bowel preparation or not. Patients who did not have mechanical bowel preparation had a normal meal on the day before the operation. Those who did were given a fluid diet, and mechanical bowel preparation with either polyethylene glycol or sodium phosphate. The primary endpoint was anastomotic leakage, and the study was designed to test the hypothesis that patients who are given mechanical bowel preparation before colorectal surgery do not have a lower risk of anastomotic leakage than those who are not. The median follow-up was 24 days (IQR 17-34). We analysed patients who were treated as per protocol. This study is registered with ClinicalTrials.gov, number NCT00288496.

FINDINGS

77 patients were excluded: 46 who did not have a bowel resection; 21 because of missing outcome data; and 10 who withdrew, cancelled, or were excluded for other reasons. The rate of anastomotic leakage did not differ between both groups: 32/670 (4.8%) patients who had mechanical bowel preparation and 37/684 (5.4%) in those who did not (difference 0.6%, 95% CI -1.7% to 2.9%, p=0.69). Patients who had mechanical bowel preparation had fewer abscesses after anastomotic leakage than those who did not (2/670 [0.3%] vs 17/684 [2.5%], p=0.001). Other septic complications, fascia dehiscence, and mortality did not differ between groups.

INTERPRETATION

We advise that mechanical bowel preparation before elective colorectal surgery can safely be abandoned.

Rectal cancer surgery without mechanical bowel preparation

BACKGROUND

: Eight randomized clinical trials and two meta-analyses recently questioned the value of preoperative mechanical bowel preparation (MBP) in colorectal surgery. However, very few patients having rectal surgery were included in these studies. The aim of this study was to assess whether rectal cancer surgery can be performed safely without MBP.

METHODS

The postoperative course was assessed in 52 consecutive unselected patients who underwent rectal cancer resection and sphincter preservation without MBP. This group was compared with a group of 61 matched patients in whom MBP was performed before surgery.

RESULTS

The overall morbidity rate after rectal resection was higher in patients who had MBP than in those who did not (51 versus 31 per cent; P = 0.036). The incidence of symptomatic anastomotic leakage was similar in the two groups (8 versus 10 per cent respectively; P = 1.000). Although not significant, peritonitis occurred more frequently in the absence of MBP (2 versus 6 per cent; P = 0.294). A trend towards a higher rate of infectious complications was noted in patients who had MBP (23 versus 12 per cent; P = 0.141), but MBP was associated with a significantly higher rate of infectious extra-abdominal complications (11 versus 0 per cent; P = 0.014). Mean hospital stay was significantly longer in the MBP group (12 versus 10 days; P = 0.022).

CONCLUSION

Elective rectal surgery for cancer without MBP may be associated with reduced postoperative morbidity.

Multicentre randomized clinical trial of mechanical bowel preparation in elective colonic resection

Background

Recent studies have suggested that MBP does not lower the risk of postoperative septic complications after elective colorectal surgery. This randomized clinical trial assessed whether preoperative MBP is beneficial in elective colonic surgery.

Methods

A total of 1505 patients, aged 18–85 years with American Society of Anesthesiologists grades I–III, were randomized to MBP or no MBP before open elective surgery for cancer, adenoma or diverticular disease of the colon. Primary endpoints were cardiovascular, general infectious and surgical-site complications within 30 days, and secondary endpoints were death and reoperations within 30 days.

Results

A total of 1343 patients were evaluated, 686 randomized to MBP and 657 to no MBP. There were no significant differences in overall complications between the two groups: cardiovascular complications occurred in 5·1 and 4·6 per cent respectively, general infectious complications in 7·9 and 6·8 per cent, and surgical-site complications in 15·1 and 16·1 per cent. At least one complication was recorded in 24·5 per cent of patients who had MBP and 23·7 per cent who did not.

Conclusion

MBP does not lower the complication rate and can be omitted before elective colonic resection. Registration number: ISRCTN28535118 (http://www.controlled-trials.com).

Laparoscopic resection of curable colon and rectal cancer: an evidence-based review

The initial enthusiastic application of laparoscopic techniques to colorectal surgical procedures was tempered in the early 1990s by reports of tumor implants in the laparoscopic incisions. Substantial evidence has accumulated, including evidence from randomized controlled trials, to support that laparoscopic resection results in oncologic outcomes similar to open resection, when performed by well-trained, experienced surgeons. This review was developed in conjunction with guidelines published by the Society of American Gastrointestinal and Endoscopic Surgeons. Data from the surgical literature concerning laparoscopic resection of curable colorectal cancer was evaluated regarding diagnostic evaluation, preoperative preparation, operative techniques, prevention of tumor implants, and training and experience. Recommendations are accompanied by an assessment of the level of supporting evidence available at the time of the development of the guidelines.

Preoperative mechanical preparation of the colon: the patient's experience

Background

Preoperative mechanical bowel preparation can be questioned as standard procedure in colon surgery, based on the result from several randomised trials.

Methods

As part of a large multicenter trial, 105 patients planned for elective colon surgery for cancer, adenoma, or diverticulitis in three hospitals were asked to complete a questionnaire regarding perceived health including experience with bowel preparation. There were 39 questions, each having 3 – 10 answer alternatives, dealing with food intake, pain, discomfort, nausea/vomiting, gas distension, anxiety, tiredness, need of assistance with bowel preparation, and willingness to undergo the procedure again if necessary.

Results

60 patients received mechanical bowel preparation (MBP) and 45 patients did not (No-MBP). In the MBP group 52% needed assistance with bowel preparation and 30% would consider undergoing the same preoperative procedure again. In the No-MBP group 65 % of the patients were positive to no bowel preparation. There was no significant difference between the two groups with respect to postoperative pain and nausea. On Day 4 (but not on Days 1 and 7 postoperatively) patients in the No-MBP group perceived more discomfort than patients in the MBP group, p = 0.02. Time to intake of fluid and solid food did not differ between the two groups. Bowel emptying occurred significantly earlier in the No-MBP group than in the MBP group, p = 0.03.

Conclusion

Mechanical bowel preparation is distressing for the patient and associated with a prolonged time to first bowel emptying.

Mechanical bowel preparation for elective colorectal surgery with primary intraperitoneal anastomosis by a single surgeon: interim analysis of a prospective single-blinded randomized trial

We report an interim analysis of a prospective single-blinded randomized trial designed to investigate whether preoperative mechanical bowel preparation influences the rate of surgical-site infection and anastomotic failure after elective colorectal surgery with primary intraperitoneal anastomosis performed by a single surgeon. Patients scheduled to undergo an elective colorectal procedure with a primary intraperitoneal anastomosis were randomized to receive either oral polyethylene glycol lavage solution and enemas (group A) or no preparation (group B). Surgical-site infection and anastomotic failure were investigated. Of 97 patients included, 48 were assigned to group A and 49 to group B. Twelve (12.4%) developed wound infections, six in each group (12.5 vs. 12.2%; NS). Intra-abdominal sepsis was only seen in group A (n = 3, 6.3%). Anastomotic failure occurred in four patients in group A (8.3%) vs. two patients in group B (4.1%) (NS). The overall complication rate in group A was 27.1%, vs. 16.3% in group B. The number needed to harm was 9.3. Our interim analysis of a prospective single-blinded randomized trial suggests that a surgeon may have the same or even worse outcomes when mechanical bowel preparation is routinely used for colorectal surgery with primary intraperitoneal anastomosis.

Preparar el colon para la cirugía. ¿Necesidad real o nada más (y nada menos) que el peso de la tradición?

Mechanical bowel preparation is a traditional procedure for preparing patients for colorectal surgery. This practice aims to reduce the risk of postoperative infectious complications since colonic fecal content has classically been related to stool spillage during surgery and anastomotic disruption. However, increasing evidence against its routine use can be found in experimental studies, clinical observations, prospective studies, and meta-analyses. We performed a review of the literature on mechanical bowel preparation and its consequences. There is no clear evidence that preoperative bowel cleansing reduces the septic complications of surgery and routine use of this procedure may increase anastomotic leaks and morbidity. Therefore, the results suggest that mechanical preparation is not required in elective colon and rectal surgery and that its use should be restricted to specific indications such as small nonpalpable tumors to aid their localization during laparoscopic procedures or to enable intraoperative colonoscopy. The role of mechanical bowel preparation in rectal surgery is not well defined and further trials with a larger number of patients are required.

The incidence of anastomotic leaks in patients undergoing colorectal surgery

BACKGROUND

There is evolving interest in auditing and credentialling the performance of surgeons. The incidence of anastomotic leakage has been proposed as a measure of performance following colorectal surgery. The aim of this study was to evaluate the incidence and risk factors associated with anastomotic leakage in patients undergoing resections of the colon and rectum.

METHODS

A prospective database was developed for all patients undergoing colorectal surgery. Anastomotic leakage was defined prior to the commencement of the study. A logistic regression analysis was performed to determine independent predictors of leakage. The variables analysed included age, sex, American Society of Anesthesiology (ASA) score, anatomical location, pathology, emergency surgery, type of anastomosis, a covering stoma and radiotherapy. Significance was defined as the probability of a type 1 error of < 5%. The results are presented as odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

There were 1598 patients who underwent 1639 anastomoses. Their mean age was 63 years, 34% of patients were ASA 3 or 4, and 16% of the operations were emergencies. Anastomotic leaks occurred in 2.4% (40/1639) of anastomoses. The leak rate for intraperitoneal anastomoses was 1.5% (19/1283) vs 6.6% for extraperitoneal anastomoses (21/316). Half of these leaks (20/40) were managed with re-operation or percutaneous drainage procedures. Ultra-low anterior resections were associated with the highest leak rate (8%, 18/225). A logistic regression analysis identified a covering stoma (P = 0.0001, OR 5.078, 95% CI 2.527-10.23) and diverticular disease (P = 0.037, OR 2.304, 95% CI 1.053-5.042) as independent predictors of a leak.

CONCLUSIONS

Within this surgical unit, the incidence of leaks from intraabdominal anastomoses was relatively low. However, leaks in patients undergoing extraperitoneal anastomoses continue to be a major cause of morbidity and mortality.

Laparoscopic colectomy without mechanical bowel preparation

BACKGROUND

Mechanical bowel preparation prior to colorectal surgery may reduce infectious complications, facilitate tumor localization, and allow intraoperative colonoscopy, if required. However, recent data suggest that mechanical bowel preparation may not facilitate a reduction in infectious complications. During laparoscopic colectomy, manual palpation is blunt, thereby potentially compromising tumor localization. The aim of this study was to assess the utility of mechanical bowel preparation in laparoscopic colectomy.

MATERIALS AND METHODS

A retrospective medical record review of all patients who underwent laparoscopic colectomy was performed. Patients were divided into two groups: those who had preoperative mechanical bowel preparation (Group A) or those who did not (Group B). All relevant perioperative data were reviewed and compared.

RESULTS

Two hundred patients underwent laparoscopic colectomy; 68 (34%) were in Group A and 132 (66%) were in Group B. Sixteen (8%) patients required intraoperative colonoscopy for localization and were evenly distributed between the two groups. The incidence of conversion to laparotomy was slightly higher in Group B (14 vs 9%) due to difficult localization in some cases; however, this difference did not reach statistical significance. Furthermore, there was no significant difference in the postoperative complication rate between the two groups. Specifically, an anastomotic leak and a wound infection were recorded in 4 and 12% of patients in Group A compared to 3 and 17% in Group B, respectively.

CONCLUSIONS

Laparoscopic colectomy may be safely performed without preoperative mechanical bowel preparation, although difficult localization may lead to a slightly higher conversion rate. Appropriate patient selection for laparoscopic colectomy without mechanical bowel preparation is essential. Furthermore, bowel preparation should be considered in cases of small and nonpalpable lesions.

Anastomotic leakage after lower gastrointestinal anastomosis: men are at a higher risk

BACKGROUND

Anastomotic leakage is the most important complication specific to intestinal surgery. The aim of this study was to review the anastomotic leakage rates in a single Colorectal Unit and to evaluate the risk factors for anastomotic leakage after lower gastrointestinal anastomosis.

METHODS

A total of 541 consecutive operations involving anastomoses of the colon and rectum that were carried out between 1999 and 2004 at a single colorectal unit were reviewed. Data concerning 35 variables, relating to patient, tumour and surgical factors, were recorded. Outcomes with respect to anastomotic leakage and mortality were recorded. Data were analysed using univariate and multivariate analyses and odds ratios (OR) calculated.

RESULTS

The overall rate of anastomotic leakage was 6.5% (35 of 541). The most frequently carried out operations were right hemicolectomy and anterior resection of the rectum, with leak rates of 2.2 and 7.4%, respectively. Univariate analysis showed that male gender (OR = 3.5), previous abdominal surgery (OR = 2.4), Crohn's disease (OR = 3.3), rectal cancer < or =12 cm from the anal verge (OR = 5.4) and prolonged operating time (OR = 2.8) were factors significantly associated with anastomotic leakage. Male gender, a history of previous abdominal surgery and the presence of a low cancer remained significant after multivariate analysis. The risk of anastomotic leakage increased when two or more risk factors were present (P < 0.01). The overall mortality was 3.7% and was higher in patients with anastomotic leakage (14.3%; P = 0.01).

CONCLUSIONS

Male gender, previous abdominal surgery and low rectal cancer are associated with increased anastomotic leakage rates. These have important implications during preoperative patient counselling and decision-making regarding defunctioning stoma formation.

[Surgical treatment of ileus. Differential diagnosis and therapeutic results]

Intestinal obstruction and ileus continue to represent a surgical challenge, regarding diagnosis and treatment. The decision when to operate is often difficult and should be based primarily on the clinical impression, although modern diagnostic tests are very helpful. Additionally, it is crucial to choose an operation that the patient can tolerate, as the spectrum of surgical interventions ranges from the taking-down of a single adhesion, that may be done laparoscopically, to sophisticated lysis of the intestine in patients with metastatic cancer in the peritoneal cavity, and simple diversion to extensive resections. These aspects are highly relevant, as good outcome can only be expected when the operation is performed correctly and optimal timing and appropriate choice of procedure are ensured.

Anastomotic disruption after large bowel resection

Anastomotic disruption is a feared and serious complication of colon surgery. Decades of research have identified factors favoring successful healing of anastomoses as well as risk factors for anastomotic disruption. However, some factors, such as the role of mechanical bowel preparation, remain controversial. Despite proper caution and excellent surgical technique, some anastomotic leaks are inevitable. The rapid identification of anastomotic leaks and the timely treatment in these cases are paramount.

Randomized clinical trial of bowel preparation with a single phosphate enema or polyethylene glycol before elective colorectal surgery

BACKGROUND

A recent meta-analysis has questioned the value of bowel preparation in patients undergoing colorectal resection. The aim of this clinical trial was to evaluate whether a single phosphate enema was as effective as oral polyethylene glycol (PEG) solution in preventing anastomotic leakage.

METHODS

Patients were randomized to receive either a single phosphate enema or 3 litres of oral PEG solution before surgery. Patients were followed for a minimum of 6 weeks to detect anastomotic leakage.

RESULTS

There were 147 patients in each group and the groups were evenly matched for putative risk factors at baseline. Patients in the enema group had more anastomotic leaks requiring reoperation than those in the PEG group (4.1 versus 0 per cent, P = 0.013; relative risk 2.04 (95 per cent confidence interval (c.i.) 1.82 to 2.30)). The mortality rate was higher in the PEG group (2.7 versus 0.7 per cent, P = 0.176; odds ratio 1.62 (95 per cent c.i. 0.45 to 36.98)).

CONCLUSION

Bowel preparation with a phosphate enema was associated with an increased risk of anastomotic leakage requiring reoperation compared with oral PEG. These results do not support the routine use of a phosphate enema in patients undergoing elective colorectal surgery.

Preoperative evaluation of colorectal cancer

Surgery is a primary modality for the treatment of patients with colorectal cancer. Before any surgical therapy, patients diagnosed with colorectal cancer require an evaluation. This preoperative evaluation can be used to assess the patient's risk associated with surgery, plan the surgical resection, and stage the patient's cancer. Staging of the cancer preoperatively is primarily of concern in rectal cancer patients. This article focuses on the elective surgical setting and the recommended preoperative evaluation of patients who have been diagnosed with colorectal cancer.

[Feasibility of colorectal surgery without colonic preparation. A prospective study]

INTRODUCTION

Mechanical bowel preparation (MBP), aimed at reducing the infectious complications of colorectal surgery, was considered as indispensable. This benefit is actually disputed. The aim of this study was to report an experience of colorectal surgery without MBP.

MATERIALS AND METHODS

Hundred ninety patients without MBP and without low residue diet, who underwent colorectal surgery with primary anastomosis not requiring a diverting stoma were included. The main outcome were the rate of mortality, anastomotic leak, wound infection and intra-abdominal abscess. Secondary outcomes were duration of intravenous perfusion, nasogastric aspiration, total hospitalisation stay and time to realimentation.

RESULTS

The procedure was performed by laparotomy (n=142) or laparoscopy (n=48). Forty-eight patients underwent emergency surgery. Ninety-two patients were operated for malignancy. The rate of mortality was 6.3% in correlation with the scale of AFC. The rate of anastomotic leak was 3.7%. The rate of specific morbidity was independent of scale of AFC on the contrary to the frequency of non-specific complications. The mean duration of intravenous perfusion and nasogastric suction were 6 days and 0.3 day. The patient had normal diet to the 4th day (4+/-3 days). The mean hospital stay was 13.4 days.

CONCLUSION

The colorectal surgery without MBP may be safely performed and could improve the quality of life of patients in the perioperatory period.

Impact of emergency surgery in the outcome of rectal and left colon carcinoma

The negative results in terms of morbidity, mortality and survival among emergency treated patients affected by colorectal cancer are well known. The specific contribution of emergency surgery to adverse outcome is not clear because of the presence in all series of other possible determinants of a poor prognosis. We used a case-control study design to compare a group of 50 patients operated on for cancer of the rectum and left colon presented as emergencies in our department during the last 14 years, and an equal number of patients who underwent elective procedures during the same period. All records of these patients were reviewed and matched for age, stage, tumor location, and medical comorbidities (coronaropathy, diabetes mellitus, cerebral vascular deficiency, chronic obstructive pulmonary disease). Outcome measures included length of hospital stay, morbidity, mortality, and actuarial 5-year survival. Univariate and multivariate analysis of factors potentially influencing survival was performed on the entire population of 100 patients. Age, tumor location, stage of disease, and medical comorbidities were well matched by intent of the study design. Overall surgical morbidity (44% versus 12% P = 0.0004), length of hospital stay (16, 64 versus 10, 97 days P = 0.0026) and postoperative mortality (4% versus 0% P = 0.4949) resulted higher in the emergency group. Actuarial overall 5-year survival was not different between the two groups. The only variables independently predictive of survival in multivariate analysis were age and rectal location of the tumor. Postoperative surgical mortality and long-term survival appear not to be influenced by emergency presentation of colorectal cancer; the negative impact of the emergency procedures is confined to the immediate postoperative period and is probably connected to the acute medical pathology often presented by patients in emergency situations. Dealing with this kind of patient's accurate preoperative assessment and solution of acute medical pathologies before surgical treatment are mandatory.

Prospective, randomised study on antibiotic prophylaxis in colorectal surgery. Is it really necessary to use oral antibiotics?

BACKGROUND AND AIMS

The use of prophylactic antibiotics in addition to mechanical cleansing is the current standard of care prior to colonic surgery. The question of whether the antibiotics should be administered intravenously or orally, or by both routes, remains controversial. Our aim was to compare three methods of prophylactic antibiotic administration in elective colorectal surgery.

METHODS

Three hundred consecutive elective colorectal resections were studied. All patients had preoperative mechanical colon cleansing with oral sodium phosphate and intravenous antibiotic prophylaxis with cefoxitin (one dose before skin incision and two postoperative doses). Patients were randomised to one of the following three groups: group A: three doses of oral antibiotic (neomycin and metronidazole) at the time of mechanical colon cleansing; group B: one dose of oral antibiotic; group C: no oral antibiotics. All patients were followed during their hospital stay and at 7, 14 and 30 days post-surgery.

RESULTS

Vomiting occurred in 31%, 11% and 9% of the studied patients (groups A, B and C, respectively) (p<0.001). Nausea was present in 44%, 18% and 13% of patients (p<0.001). Abdominal pain was recorded in 13%, 10% and 4% of patients (p: 0.077). Wound infection was present in 7%, 8% and 6% and suture dehiscence occurred in 2%, 2% and 3% of the patients in the three groups (no differences among them). Neither were differences found among the three groups in terms of urinary infections, pneumonia, postoperative ileus or intra-abdominal abscess.

CONCLUSION

The addition of three doses of oral antibiotics to intravenous antibiotic prophylaxis is associated with lower patient tolerance in terms of increased nausea, vomiting and abdominal pain, and has shown no advantages in the prevention of postoperative septic complications. Therefore, we recommend that oral antibiotics should not be used prior to colorectal surgery.

Bowel preparation is associated with spillage of bowel contents in colorectal surgery

PURPOSE

Infectious complications pose a significant cause of morbidity in colon and rectal surgery. This study was designed to assess the effect of bowel preparation on spillage of bowel contents into the peritoneal cavity during colorectal surgery, and its potential effect on the rate of postoperative infectious complications.

METHODS

The quality of bowel preparation and the incidence of spillage of bowel contents were prospectively assessed in patients undergoing elective colon and rectal resection. The patients were followed for 30 days for postoperative infectious and noninfectious complications.

RESULTS

A total of 333 patients were included in this study, of which 181 did not receive mechanical bowel preparation. Intraoperative spillage of bowel contents occurred in 48 patients (14 percent), whereas in 285 patients (86 percent), spillage did not occur. There was a trend toward a higher rate of overall surgical infectious and noninfectious complications in patients who had spillage of bowel contents compared with patients without spillage; however, this difference was not statistically significant (18.7 vs. 11 percent, and 29 vs. 19 percent, respectively). Preoperative mechanical bowel preparation and colocolonic or colorectal anastomosis was associated with a higher rate of bowel contents spillage, although this difference did not reach statistical significance. Liquid colonic contents caused significantly higher rates of spillage.

CONCLUSIONS

Spillage of bowel contents into the peritoneal cavity during colon and rectal surgery may increase the rate of postoperative infectious complications. In addition, inadequate mechanical bowel preparation, leading to liquid bowel contents, increases the rate of intraoperative spillage.

Mechanical bowel preparation or not? Outcome of a multicenter, randomized trial in elective open colon surgery

PURPOSE

Mechanical bowel preparation is common practice in elective colon surgery. In recent literature the value of this procedure is under discussion. To verify the value of mechanical bowel preparation in elective open colon surgery, a randomized clinical trial was conducted.

METHODS

During a prospective, multicenter, randomized study, 250 patients undergoing elective open colon surgery were randomized between receiving mechanical bowel preparation with polyethylene glycol (PEG group, 125 patients) and having a normal meal preoperatively (normal meal preoperatively group, 125 patients). Outcome parameters were wound infection with bacterial results of intraoperative swabs and anastomotic leak.

RESULTS

In the polyethylene glycol group there were a total of nine wound infections (7.2 percent) and seven anastomotic leaks (5.6 percent) compared with seven wound infections (5.6 percent) (P = 0.61) and six anastomotic leaks (4.8 percent) (P = 0.78) in the normal meal preoperatively group. Bacterial results showed 52 percent sterile subcutis swabs in the PEG group and 63 percent sterile subcutis swabs in the normal meal preoperatively group (P = 0.11).

CONCLUSION

In the present study we could not detect a difference in outcome parameters between patients receiving mechanical bowel preparation in elective open colon surgery and patients without preoperative treatment of the bowel. The present study, although underpowered, did not show a difference in the primary outcome of bacterial wound cultures between patients receiving preoperative mechanical bowel preparation and patients receiving no preoperative bowel treatment. We conclude that there may be no need to continue the use of mechanical bowel preparation in elective open colon surgery.

Anterior Resection of Rectal Cancer Without Bowel Preparation and Diverting Stoma

PURPOSE

Since the introduction of total mesorectal excision (TME) as the standard operation technique for rectal cancer, anastomotic leakage percentages of up to 18% have been reported. To prevent such leakage, the use of mechanical bowel preparation and also the construction of a diverting ileostoma or colostomy have been standard procedures for years. In our institute, however, all patients undergoing colorectal surgery are operated upon without these measures. The present study was undertaken to investigate the results of this strategy in terms of the occurrence of postoperative anastomotic leakage.

METHODS

All patients who underwent an elective (low) anterior resection between January 1996 and December 2001 (n = 144) entered the study. The clinical and pathological records of these patients were reviewed retrospectively. The exclusion criteria were patients with fixed rectal carcinoma who received preoperative radiotherapy and/or a stoma only at operation, emergency operations, abdominoperoneal resections, and Hartmann's procedures.

RESULTS

Anastomotic leakage occurred in 7 out of 144 patients (4.9%). There was a trend toward a higher leakage frequency in men, in patients with a distal anastomosis, in patients with a stapled anastomosis, and in patients with a T3-T4 tumor or with positive lymph nodes. None of these factors, however, had a significant prognostic value based on a univariate or multivariate analysis. Those who died after leakage tended to be older than those who did not (P < 0.05).

CONCLUSION

A (low) anterior resection can be performed safely without mechanical bowel preparation or a diverting stoma, and results in an anastomotic leakage percentage of less than 5%. Appropriate selection of patients may be important, but none of the investigated patient- or tumor-related factors could be identified as decisive.

Mortality and morbidity after surgery of mid and low rectal cancer. Results of a French prospective multicentric study

BACKGROUND

The aim of the study was to assess both mortality and morbidity following resection of mid and low rectal cancers in a French prospective multicentric study.

PATIENTS

From June to September 2002, consecutive patients undergoing resection for cancer of the mid- or lower rectum were prospectively included in a multicentric study. Both postoperative mortality and morbidity were recorded. Multivariate statistical analysis was performed in order to assess risk factors predictive of postoperative morbidity.

RESULTS

238 patients with a mean age of 66 +/- 13 years (range: 26-88) were included. Neoadjuvant radiotherapy was performed in 68% of the patients. Total mesorectal excision was performed in 218 patients (92%), of whom 151 (63%) had a sphincter saving procedure. Six patients died (2.5%). Overall postoperative morbidity rate was 43%, including anastomotic leakage (11%) and reoperation (5%). Mean hospital-in-stay was 20 +/- 16 days (range: 3191). Four independent risk factors of morbidity were found: perioperative fecal contamination (OR = 3.9 [1.1; 13.5]), mean operating time longer than 6 hours (OR = 4.5 [1.7; 12.1]), ASA score > 2 (OR = 3.2 [1.6; 7.9]), and smocking (OR = 3.3 [1.2; 8.9]).

CONCLUSIONS

Resection of cancer involving the middle or lower rectum with sphincter saving procedures was possible in two-thirds of the patients and was associated with 2.5% mortality and 43% morbidity.

Pre-operative mechanical bowel cleansing or not? an updated meta-analysis

OBJECTIVES

Pre-operative mechanical bowel preparation has been considered an efficient regimen against leakage and infectious complications, after colorectal resections. This dogma is based only on observational data and experts' opinions. The aim of this study was to evaluate the efficacy and safety of prophylactic pre-operative mechanical bowel preparation before elective colorectal surgery.

METHODS

EMBASE, LILACS, MEDLINE and The Cochrane Library and abstracts from major gastroenterological congresses were searched. No language restrictions were applied. The selection criterion used was randomised clinical trials (RCT) comparing any kind of mechanical bowel preparation with no preparation in patients submitted to elective colorectal surgery and where anastomotic leakage, mortality, and wound infection were outcome measurements. Data were independently extracted by the reviewers and cross-checked. The methodological quality of each trial was assessed by the same reviewers. For meta-analysis the Peto-Odds ratio was used.

RESULTS

Of 1592 patients (9 RCTs), 789 were allocated to mechanical bowel preparation (Group A) and 803 to no preparation (Group B) before elective colorectal surgery. Anastomotic leakage developed in 48 (6%) of 772 patients in A compared with 25 (3.2%) of 777 patients in B; Peto OR 2.03, 95% (CI: 1.28-3.26; P = 0.003). Wound infection occurred in 59 (7.4%) of 791 patients in A and in 43 (5.4%) of 803 patients in B; Peto OR 1.46, 95% (CI: 0.97-2.18; P = 0.07); Five (1%) of 509 patients died in group in A compared with 3 (0.61%) of 516 patients in group B; Peto OR 1.72, 95% (CI: 0.43-6.95; nonsignificant).

CONCLUSION

There is no evidence that patients benefit from mechanical bowel preparation. On the contrary taking colorectal surgery as a whole, pre-operative bowel cleansing leads to a higher rate of anastomotic leakage. The dogma that mechanical bowel preparation is necessary before elective colorectal surgery has to be reconsidered.

Elective intestinal operations in infants and children without mechanical bowel preparation: a pilot study

BACKGROUND/PURPOSE

Preoperative mechanical bowel preparation (MBP) for elective intestinal operations has been a long accepted practice. However, MBP is often unpleasant and time-consuming for patients, and clinical trials in adults have not shown improved outcomes. We conducted this pilot study to test whether omitting MBP before elective intestinal operations in infants and children would increase the risk of infectious or anastomotic complications.

METHODS

Retrospective review was performed of 143 patients who had an elective colon or distal small bowel procedure performed at our children's hospital between 1990 and 2003.

RESULTS

Thirty-three patients (No PREP) were managed by a single surgeon who routinely omitted MBP, whereas another 110 patients (PREP) were prepared with enemas, laxatives, or both. Both groups received 24 hours of preoperative dietary restriction to clear liquids and perioperative parenteral antibiotics. The No PREP group had one anastomotic leak and no wound infections, whereas the PREP group had 2 anastomotic leaks and 1 wound infection (P = .58). These results occurred despite greater duration of antibiotic therapy and incidence of delayed wound closures in the PREP group.

CONCLUSION

The results of this pilot study suggest that omitting MBP before elective intestinal operations in infants and children carries no increased risk of infectious or anastomotic complications. Eliminating MBP may reduce health care costs and inconvenience to patients. These findings warrant a large, prospective, randomized clinical trial to validate our findings and to investigate further the necessity of MBP in the pediatric population.

Randomized clinical trial of mechanical bowel preparation versus no preparation before elective left-sided colorectal surgery

BACKGROUND

Mechanical bowel preparation (MBP) is performed routinely before colorectal surgery to reduce the risk of postoperative infectious complications. The aim of this randomized clinical trial was to compare the outcome of patients who underwent elective left-sided colorectal surgery with or without MBP.

METHODS

Patients scheduled for elective left-sided colorectal resection with primary anastomosis were randomized to preoperative MBP (3 litres of polyethylene glycol) (group 1) or surgery without MBP (group 2). Postoperative abdominal infectious complications and extra-abdominal morbidity were recorded prospectively.

RESULTS

One hundred and fifty-three patients were included in the study, 78 in group 1 and 75 in group 2. Demographic, clinical and treatment characteristics did not differ significantly between the two groups. The overall rate of abdominal infectious complications (anastomotic leak, intra-abdominal abscess, peritonitis and wound infection) was 22 per cent in group 1 and 8 per cent in group 2 (P = 0.028). Anastomotic leak occurred in five patients (6 per cent) in group 1 and one (1 per cent) in group 2 (P = 0.210) [corrected] Extra-abdominal morbidity rates were 24 and 11 per cent respectively (P = 0.034). Hospital stay was longer for patients who had MBP (mean(s.d.) 14.9(13.1) versus 9.9(3.8) days; P = 0.024).

CONCLUSION

Elective left-sided colorectal surgery without MBP is safe and is associated with reduced postoperative morbidity.

Prospective, randomized trial comparing intraoperative colonic irrigation with manual decompression only for obstructed left-sided colorectal cancer

BACKGROUND

This is a prospective, randomized, controlled trial comparing the outcome of intraoperative colonic irrigation with that of manual decompression for acutely obstructing colorectal cancers distal to the splenic flexure.

METHODS

All patients admitted to our department from June 1999 to August 2002 with obstructing left-sided colorectal cancers were recruited. Patients were randomized intraoperatively and were excluded if deemed unsuitable for segmental resection and primary anastomosis. Twenty-five patients were randomized to receive colonic irrigation and twenty-eight to receive manual decompression. Perioperative parameters and outcome including mortality and anastomotic leak were recorded.

RESULTS

Both groups of patients were comparable in terms of gender and age. The time taken for mobilization, decompression, and irrigation in the colonic irrigation group (median, 31 minutes) was significantly longer than that for the manual decompression group (median, 13 minutes) (P; = 0.0005). However, the total time of the operation was similar for both groups. Times for recovery of bowel function, of wound infection, and until discharge from the hospital were also similar. In the manual decompression group there were two cases of anastomotic leak (8 percent, 2/25) requiring reoperation but none (0/24) in the colonic irrigation group. However, this difference was not statistically significant.

CONCLUSION

Manual decompression of proximal colon without irrigation is as safe as colonic irrigation in one-stage surgical management of obstructing left-sided colorectal cancer.

Mechanical bowel preparation for elective colorectal surgery

BACKGROUND

For over a century the presence of bowel content during surgery has been linked to anastomotic leakage. Mechanical bowel preparation has been considered an efficient agent against leakage and infectious complications. This dogma is not based on solid evidence, but on observational data and expert's opinions.

OBJECTIVES

To determine the effectiveness and safety of prophylactic mechanical bowel preparation for morbidity and mortality rates in elective colorectal surgery.

SEARCH STRATEGY

We searched MEDLINE, EMBASE, LILACS, and the Cochrane Central Register of Controlled Trials. We also searched relevant medical journals, and conference proceedings from major gastroenterological congresses and contacted experts in the field. We used the search strategy described by the Colorectal Cancer Review Group, without limitations for date of publication and language. I SELECTION CRITERIA: Randomised, clinical trials that compared any strategy in mechanical bowel preparation with no mechanical bowel preparation.

DATA COLLECTION AND ANALYSIS

Data were independently extracted by the reviewers and cross-checked. The same reviewers assessed the methodological quality of each trial. Details of the randomisation (generation and concealment), blinding, whether an intention-to-treat analysis was done, and the number of patients lost to follow-up was recorded. For analysis the Peto odds ratio (OR) was used as defaults.

MAIN RESULTS

Of the 1592 patients (9 trials), 789 were allocated to mechanical bowel preparation (Group A) and 803 to no preparation (Group B) before elective colorectal surgery. For anastomotic leakage (main outcome) the results were: - Low anterior resection: 9.8% (11 of 112 patients in Group A) compared with 7.5% (9 of 119 patients in Group B); Peto OR 1.45, 95% confidence interval (CI): 0.57 to 3.67 (non-significant); - Colonic surgery: 2.9% (Group A) compared with 1.6% (Group B) ; Peto OR 1.80, 95% CI: 0.68 to 4.75 (non-significant); Overall anastomotic leakage: 6.2% (Group A) compared with 3.2% (Group B); Peto OR 2.03, 95% CI: 1.276 to 3.26 (p=0.003). For the secondary outcome of wound infection the result was: 7.4% (Group A) compared with 5.4% (Group B); Peto OR 1.46, 95% CI: 0.97 - to 2.18 (p=0.07); Sensitivity analyses excluding studies with dubious randomisation, studies published as abstracts only, and studies involving children did not change the overall conclusions

AUTHORS' CONCLUSIONS

There is no convincing evidence that mechanical bowel preparation is associated with reduced rates of anastomotic leakage after elective colorectal surgery. On the contrary, there is evidence that this intervention may be associated with an increased rate of anastomotic leakage and wound complications. It is not possible to be conclusion on the latter issue because of the clinical heterogeneity of trial inclusion criteria, methodological inadequacies in trial (in particular, poor reporting of concealment and allocation), potential performance biases, and failure of intention-to-treat analyses. Nevertheless, the dogma that mechanical bowel preparation is necessary before elective colorectal surgery should be reconsidered.

[Preoperative bowel preparation--is it useful?]

Mechanical cleansing of the colon prior to elective colorectal surgery is a dogmatically established belief in surgery. Polyethylene glycol was extensively used in the 1980's and 1990's but has been largely replaced by other laxative solutions such as sodium phosphate which are better tolerated by the patient. Evidence-based data in the surgical literature question the dogma of routine mechanical bowel cleansing (8 randomized controlled studies and 4 meta-analyses). These data show with a good level of evidence that mechanical bowel preparation is unnecessary and perhaps harmful.

Fast-track surgery: the Heidelberg experience

Fast-track surgery is an interdisciplinary multimodal concept of minimally invasive surgery or new incision lines and "cutting old plaits" (e.g., the use of drains or tubes). It uses modern intraoperative anesthesia (e.g., fluid restriction) and analgesia, including new drugs and novel ways of administration (e.g., thoracic epidural analgesia) for postoperative pain relief, in combination with the immediate mobilization of the patient and early oral nutrition after the operation. This approach requires a cooperating team of motivated nurses, physiotherapists, anesthesiologists, and surgeons, in addition to continuous improvement of the processes involved. Moreover, extended patient education and information about the procedures and the expected time course are of the highest importance, as the active role of the patient is to be emphasized. This chapter describes the development and implementation of fast-track surgery in colorectal diseases at the Department of Surgery of the University Hospital of Heidelberg, Germany. Preliminary results of fast-track surgery suggest a significant and clear overall benefit for the patient. A shorter hospital stay and reduced systemic morbidity in addition to no increase in postoperative complications on an out-patient basis were found. However, to exclude a "bloody discharge" of the patients, thorough follow-up and quality control are mandatory. Although in the initial phase increased personnel care is necessary, in the new German reimbursement system with G-DRGs (German diagnosis-related groups) fast-track surgery seems to save resources in the long term.

Meta-analysis of randomized clinical trials of colorectal surgery with or without mechanical bowel preparation

BACKGROUND

Mechanical bowel preparation is used routinely before colorectal surgery, but some randomized clinical trials have suggested that it is of no benefit. This study assesses whether such bowel preparation may safely be omitted before elective colorectal surgery.

METHODS

A search of the literature was performed; the inclusion criteria were randomized clinical trials comparing bowel preparation with no preparation in colorectal surgery. The methodological quality of included trials was assessed. The primary outcome was anastomotic leakage; secondary outcomes were other septic complications. The meta-analysis was conducted using the Peto one-step method.

RESULTS

Eleven trials were retrieved, of which seven, containing 1454 patients, were included in the meta-analysis. There was no heterogeneity between the trials. Significantly more anastomotic leakage was found after mechanical bowel preparation (5.6 versus 3.2 per cent; odds ratio 1.75 (95 per cent confidence interval 1.05 to 2.90); P = 0.032). All other endpoints (wound infection, other septic complications and non-septic complications) also favoured the no-preparation regimen, but the differences were not statistically significant. Sensitivity analysis showed that these results were similar when trials of poor quality were excluded. Subgroup analysis showed that anastomotic leakage was significantly greater after bowel preparation with polyethylene glycol (PEG) compared with no preparation, but not after other types of preparation.

CONCLUSION

There is good evidence to suggest that mechanical bowel preparation using PEG should be omitted before elective colorectal surgery. Other bowel preparations should be evaluated by further large randomized trials.

What Proportion of Patients with an Ostomy (for Diverticulitis) Get Reversed?

A common operation for patients with complicated sigmoid diverticulitis is resection and placement of an ostomy (Hartmann procedure). This population-based study examines that proportion of ostomates who undergo reversal. In the California inpatient file, patients admitted for acute diverticulitis in 1995 were identified, including a subset that had surgical resection. Data regarding receipt of ostomy were obtained (4-year follow-up). Demographics and clinical data (procedure, ostomy reversal, time to reversal, comorbidity score, and complications) were collected. In 1995, 11,582 admissions for diverticulitis occurred in California. Of these, 24.2 per cent (n = 2808) underwent surgery at admission; 88.9 per cent were sigmoid/left colectomies; and 41.7 per cent had a Hartmann procedure. Patients with ostomies were older ( P = 0.0004) and male ( P = 0.03). Median comobidity score was the same for patients with or without an ostomy. Of the 1176 patients who had the Hartmann procedure, 65 per cent underwent reversal (mean 143 days). A larger proportion of men than women had their ostomies reversed (74.5% vs 55.9%, respectively, P < 0.0001). Median comorbidity scores for both groups were low, 0 for those reversed and 1 for nonreversed. Our study shows that although the majority of patients had their ostomies reversed, over 35 per cent did not at 4-year follow-up. Further studies are required to evaluate how this rate may be improved.

Mechanical bowel preparation in the older surgical patient

A major risk of colon resection is contamination from the bowel. Poor cleansing of the colon has been associated with an increased incidence of wound infections and intra-abdominal abscesses. Despite controversy on the usefulness of colon cleansing methods, mechanical bowel preparation along with oral and intravenous antibiotics have become common preoperative practice. The population is aging, and surgeons and endoscopists are going to be increasingly involved in the care of older patients. This review focuses on various colon cleansing methods and examines specific issues in older patients.