Oral antibiotics (OA) combined with mechanical bowel preparation (MBP) significantly decrease the rate of surgical site infections (SSIs). However, the prophylactic effects in region-specific colorectal surgery have not been assessed.

A single-centre, single-blind, randomized controlled trial was conducted from 2019 to 2022. Patients were eligible if they were diagnosed with nonmetastatic colorectal malignancy, and laparoscopic colorectal surgery was indicated. Participants were randomly assigned (1:1) to the experimental (OA+MBP preparation) or control group (MBP preparation). The randomization was further stratified by resected region. The primary outcome was the incidence of SSIs. Patients were followed up for 1 month postoperatively, and all complications were recorded.

Between 2019 and 2022, 157 and 152 patients were assigned to the experimental and control groups, respectively, after 51 patients were excluded. The incidence of SSIs in the control group (27/152) was significantly higher than that in the experimental group (13/157; P =0.013), as was the incidence of superficial SSIs (5/157 vs. 14/152, P =0.027) and deep SSIs (7/157 vs. 16/152, P =0.042). After redistribution according to the resected region, the incidence of SSIs was significantly higher in the control group with left-sided colorectal resection (descending, sigmoid colon, and rectum) (9/115 vs. 20/111, P =0.022) but was similar between the groups with right-sided colon resection (ascending colon) (3/37 vs. 7/36, P =0.286). No differences were noted between the groups in terms of other perioperative complications.

OA+MBP before colorectal surgery significantly reduced the incidence of SSIs. Such a prophylactic effect was particularly significant for left-sided resection. This preparation mode should be routinely adopted before elective left-region colorectal surgeries.

Bowel preparation before colectomy is considered an effective strategy to decrease postoperative complications. However, data regarding the effect of bowel preparation in patients undergoing minimally invasive colectomy are limited. The aim of this study was to investigate the role of different bowel preparation strategies in patients undergoing open, minimally invasive, and converted-to-open elective colectomies.

We identified 39,355 patients who underwent elective colectomy from the American College of Surgeons National Surgical Quality Improvement Program colectomy-targeted database (2012-2016). Multivariate logistic regression models were used to assess the impact of different bowel preparation strategies on postoperative complications and mortality in three subapproach groups: open (n = 12,141), minimally invasive (n = 23,057), and converted to open (n = 4157).

Overall, a total of 10,066 (25.6%) patients received no preparation (NP), 11,646 (29.5%) mechanical bowel preparation (MBP) alone, 1664 (4.2%) antibiotic bowel preparation (ABP) alone, and 15,979 (40.6%) MBP + ABP. Compared with NP, MBP + ABP showed the strongest protective effects. MBP + ABP was associated with reduced risk of major complications (odds ratio [OR] = 0.60, 95% confidence interval [CI]: 0.55-0.66), infectious complications (OR = 0.50, 95% CI: 0.46-0.54), any complications (OR = 0.55, 95% CI: 0.51-0.60), 30-d mortality (OR = 0.68, 95% CI: 0.48-0.96), anastomotic leak (OR = 0.50, 95% CI: 0.43-0.58), and length of stay ≥ 4 d (OR = 0.64, 95% CI: 0.61-0.67) in overall population. These protective effects, except for 30-d mortality, were observed in open, minimally invasive, and converted-to-open groups. When the analysis was limited to robotic surgery only, MBP + ABP was only associated with reduced risk of major complications (OR = 0.61, 95% CI: 0.38-0.97) compared with NP. The protective effects remained similar over the study time period.

MBP + ABP is a preferred preoperative strategy in open, minimally invasive, and converted-to-open colectomy.

To analyze potential benefits with regards to infectious complications with combined use of mechanical bowel preparation (MBP) and ABP in elective colorectal resections.

Despite recent literature suggesting that MBP does not reduce infection rate, it still is commonly used. The use of oral antibiotic bowel preparation (ABP) has been practiced for decades but its use is also controversial.

Patients undergoing elective colorectal resection in the 2012 to 2015 American College of Surgeons National Surgical Quality Improvement Program cohorts were selected. Doubly robust propensity score-adjusted multivariable regression was conducted for infectious and other postoperative complications.

A total of 27,804 subjects were analyzed; 5471 (23.46%) received no preparation, 7617 (32.67%) received MBP only, 1374 (5.89%) received ABP only, and 8855 (37.98%) received both preparations. Compared to patients receiving no preparation, those receiving dual preparation had less surgical site infection (SSI) [odds ratio (OR) = 0.39, P < 0.001], organ space infection (OR = 0.56, P ≤ 0.001), wound dehiscence (OR = 0.43, P = 0.001), and anastomotic leak (OR = 0.53, P < 0.001). ABP alone compared to no prep resulted in significantly lower rates of surgical site infection (OR = 0.63, P = 0.001), organ space infection (OR = 0.59, P = 0.005), anastomotic leak (OR = 0.53, P = 0.002). MBP showed no significant benefit to infectious complications when used as monotherapy.

Combined MBP/ABP results in significantly lower rates of SSI, organ space infection, wound dehiscence, and anastomotic leak than no preparation and a lower rate of SSI than ABP alone. Combined bowel preparation significantly reduces the rates of infectious complications in colon and rectal procedures without increased risk of Clostridium difficile infection. For patients undergoing elective colon or rectal resection we recommend bowel preparation with both mechanical agents and oral antibiotics whenever feasible.

It has been a standard practice to perform mechanical bowel preparation (MBP) prior to colorectal surgery to reduce the risk of colorectal anastomotic leakages (CAL). The latest Cochrane systematic review suggests there is no benefit for MBP in terms of decreasing CAL, but new studies have been published. The aim of this systematic review and meta-analysis is to update current evidence for the effectiveness of preoperative MBP on CAL in patients undergoing colorectal surgery. Consequently, PubMed, MEDLINE, Embase, CENTRAL and CINAHL were searched from 2010 to March 2017 for randomised controlled trials (RCT) that compared the effects of MBP in colorectal surgery on anastomotic leakages. The outcome CAL was expressed in odds ratios and analysed with a fixed-effects analysis in a meta-analysis. Quality assessment was performed by the cochrane risk of bias tool and grades of recommendation, assessment, development and evaluation (GRADE) methodology. Eight studies (1065 patients) were included. The pooled odds ratio showed no significant difference of MBP in colorectal surgery on CAL (odds ratio (OR) = 1.15, 95% CI = 0.68-1.94). According to GRADE methodology, the quality of the evidence was low. To conclude, MBP for colorectal surgery does not lower the risk of CAL. These results should, however, be interpreted with caution due to the small sample sizes and poor quality. Moreover, the usefulness of MBP in rectal surgery is not clear due to the lack of stratification in many studies. Future research should focus on high-quality, adequately powered RCTs in elective rectal surgery to determine the possible effects of MBP.

Nosocomial infections are the most frequent complications observed in surgical patients. In colorectal surgery, the opening of the viscera causes the dissemination into the operative field of microorganisms originating from endogenous sources, increasing the chance of developing postoperative complications. It is reported that without antibiotic prophylaxis, wound infection after colorectal surgery develops in approximately 40% of patients. This percentage decreases to approximately 11% after antibiotic prophylaxis. Specific criteria in the choice of correct antibiotic prophylaxis have to be respected, on the basis of the microorganisms usually found in the surgical site, and on the specific hospital microbiologic epidemiology.

We retrospectively evaluated the usefulness of sennoside as an agent for mechanical bowel preparation prior to elective colon cancer surgery.

A total of 86 patients were given 12 mg of sennoside on the evening prior to resective surgery for colon cancer, followed by intravenous antimicrobial prophylaxis used on the day of surgery or until postoperative day 2.

The incidence of surgical site infection in the study group was 4.7%, which was comparable to that in the historical control patients (3.5%, p>0.99), who had received polyethylene glycol for mechanical bowel preparation prior to colon surgery. On multivariate logistic regression analysis, only body mass index (p=0.04) was an independent significant factor affecting the surgical site infection. The intraoperative spillage was not influenced by the presence of stenosis, although the amount of fecal matter was higher in the upstream colon segment (p<0.01) and downstream segment (p=0.07) in patients with a stenotic lesion occupying more than two-thirds of the lumen (n=29) than in those without such severe stenosis (n=57).

Sennoside seems to be an acceptable agent for mechanical bowel preparation even in patients with stenosis.

The presence of bowel contents during colorectal 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.An enema before the rectal surgery to clean the rectum and facilitate the manipulation for the mechanical anastomosis is used for many surgeons. This is analysed separately

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

Publications describing trials of MBP before elective colorectal surgery were sought through searches of MEDLINE, EMBASE, LILACS, IBECS and The Cochrane Library; by handsearching relevant medical journals and conference proceedings, and through personal communication with colleagues.Searches were performed December 1, 2010.

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 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).

At this update six trials and a new comparison (Mechanical bowel preparation versus enema) were added. Altogether eighteen trials were analysed, with 5805 participants; 2906 allocated to MBP (Group A), and 2899 to no preparation (Group B), before elective colorectal surgery.For the comparison Mechanical Bowel Preparation Versus No Mechanical Bowel Preparation results were:1. Anastomotic leakage for low anterior resection: 8.8% (38/431) of Group A, compared with 10.3% (43/415) of Group B; Peto OR 0.88 [0.55, 1.40].2. Anastomotic leakage for colonic surgery: 3.0% (47/1559) of Group A, compared with 3.5% (56/1588) of Group B; Peto OR 0.85 [0.58, 1.26].3. Overall anastomotic leakage: 4.4% (101/2275) of Group A, compared with 4.5% (103/2258) of Group B; Peto OR 0.99 [0.74, 1.31].4. Wound infection: 9.6% (223/2305) of Group A, compared with 8.5% (196/2290) of Group B; Peto OR 1.16 [0.95, 1.42].Sensitivity analyses did not produce any differences in overall results.For the comparison Mechanical Bowel Preparation (A) Versus Rectal Enema (B) results were:1. Anastomotic leakage after rectal surgery: 7.4% (8/107) of Group A, compared with 7.9% (7/88) of Group B; Peto OR 0.93 [0.34, 2.52].2. Anastomotic leakage after colonic surgery: 4.0% (11/269) of Group A, compared with 2.0% (6/299) of Group B; Peto OR 2.15 [0.79, 5.84].3. Overall anastomotic leakage: 4.4% (27/601) of Group A, compared with 3.4% (21/609) of Group B; Peto OR 1.32 [0.74, 2.36].4. Wound infection: 9.9% (60/601) of Group A, compared with 8.0% (49/609) of Group B; Peto OR 1.26 [0.85, 1.88].

Despite the inclusion of more studies with a total of 5805 participants, there is no statistically significant evidence that patients benefit from mechanical bowel preparation, nor the use of rectal enemas. In colonic surgery the bowel cleansing can be safely omitted and induces no lower complication rate. The few studies focused in rectal surgery suggested that mechanical bowel preparation could be used selectively, even though no significant effect was found. Further research on patients submitted for elective rectal surgery, below the peritoneal verge, in whom bowel continuity is restored, and studies with patients submitted to laparoscopic surgeries are still warranted.

The presence of bowel contents during colorectal 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.An enema before the rectal surgery to clean the rectum and facilitate the manipulation for the mechanical anastomosis is used for many surgeons. This is analysed separately

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

Publications describing trials of MBP before elective colorectal surgery were sought through searches of MEDLINE, EMBASE, LILACS, IBECS and The Cochrane Library; by handsearching relevant medical journals and conference proceedings, and through personal communication with colleagues.Searches were performed December 1, 2010.

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 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).

At this update six trials and a new comparison (Mechanical bowel preparation versus enema) were added. Altogether eighteen trials were analysed, with 5805 participants; 2906 allocated to MBP (Group A), and 2899 to no preparation (Group B), before elective colorectal surgery.For the comparison Mechanical Bowel Preparation Versus No Mechanical Bowel Preparation results were:1. Anastomotic leakage for low anterior resection: 8.8% (38/431) of Group A, compared with 10.3% (43/415) of Group B; Peto OR 0.88 [0.55, 1.40].2. Anastomotic leakage for colonic surgery: 3.0% (47/1559) of Group A, compared with 3.5% (56/1588) of Group B; Peto OR 0.85 [0.58, 1.26].3. Overall anastomotic leakage: 4.4% (101/2275) of Group A, compared with 4.5% (103/2258) of Group B; Peto OR 0.99 [0.74, 1.31].4. Wound infection: 9.6% (223/2305) of Group A, compared with 8.5% (196/2290) of Group B; Peto OR 1.16 [0.95, 1.42].Sensitivity analyses did not produce any differences in overall results.For the comparison Mechanical Bowel Preparation (A) Versus Rectal Enema (B) results were:1. Anastomotic leakage after rectal surgery: 7.4% (8/107) of Group A, compared with 7.9% (7/88) of Group B; Peto OR 0.93 [0.34, 2.52].2. Anastomotic leakage after colonic surgery: 4.0% (11/269) of Group A, compared with 2.0% (6/299) of Group B; Peto OR 2.15 [0.79, 5.84].3. Overall anastomotic leakage: 4.4% (27/601) of Group A, compared with 3.4% (21/609) of Group B; Peto OR 1.32 [0.74, 2.36].4. Wound infection: 9.9% (60/601) of Group A, compared with 8.0% (49/609) of Group B; Peto OR 1.26 [0.85, 1.88].

Despite the inclusion of more studies with a total of 5805 participants, there is no statistically significant evidence that patients benefit from mechanical bowel preparation, nor the use of rectal enemas. In colonic surgery the bowel cleansing can be safely omitted and induces no lower complication rate. The few studies focused in rectal surgery suggested that mechanical bowel preparation could be used selectively, even though no significant effect was found. Further research on patients submitted for elective rectal surgery, below the peritoneal verge, in whom bowel continuity is restored, and studies with patients submitted to laparoscopic surgeries are still warranted.

Mechanical bowel preparation is routinely done before colon and rectal surgery, aimed at reducing the risk of postoperative infectious complications. The aim of the study was to assess whether elective colon and rectal surgery can be safely performed without preoperative mechanical bowel preparation.

Patients undergoing elective colon and rectal resections with primary anastomosis were prospectively randomized into two groups. Group A had mechanical bowel preparation with polyethylene glycol before surgery, and group B had their surgery without preoperative mechanical bowel preparation. Patients were followed up for 30 days for wound, anastomotic, and intra-abdominal infectious complications.

Two hundred forty four patients were included in the study, 120 in group A and 124 in group B. Demographic characteristics, type of surgical procedure and type of anastomosis did not significantly differ between the two groups. There was no difference in the rate of surgical infectious complications between the two groups but the overall infectious complications rate was 20.0% in group A and 11.3% in group B (p .05). Wound infection (p = 0.18), anastomotic leak (p = 0.52), and intra-abdominal abscess (p = 0.36) occurred in 9.2%, 5.8%, and 5.0% versus 4.8%, 4.0%, and 2.4%, respectively. No mechanical bowel preparation seems to be safe also in rectal surgery.

These results suggest that elective colon and rectal surgery may be safely performed without mechanical preparation.

The aim of this study was to estimate efficacy of mechanical bowel preparation with polyethylene glycol (PEG) in prevention of postoperative complications in elective colorectal surgery.

A literature search of MEDLINE (PubMed), EMBASE, and the Cochrane Library was done to identify randomized controlled trials involving comparison of postoperative complications after mechanical bowel preparation with PEG (PEG group) and no preparation (control group). A meta-analysis was set up to distinguish overall difference between the two groups.

A total of five randomized controlled trials was identified according to our inclusion criteria. The use of PEG for mechanical bowel preparation did not significantly reduce the rate of surgical site infection (SSI; odds ratio (OR) 95% confidence interval (CI), 1.39 (0.85-2.25); P = 0.19) including incisional SSI (OR 95% CI, 1.44 (0.88-2.33); P = 0.15), organ/space SSI (OR 95% CI, 1.10 (0.43-2.78); P = 0.49), anastomotic leak (OR 95% CI,1.78 (0.95-3.33; P = 0.07), mortality (OR 95% CI, 1.24 (0.37-4.14; P = 0.73), infectious complications (OR 95% CI, 1.14 (0.62-2.08); P = 0.67), and hospital stay (weighted mean difference 95% CI, 2.17 (-2.90-7.25); P = 0.40) except main complications (OR 95% CI, 1.76 (1.09-2.85); P = 0.02), of which the rate increased significantly in the PEG group.

The use of mechanical bowel preparation with PEG does not significantly lower postoperative complications in elective colorectal surgery.

Numerous reports on reproductive pathology in all rhinoceros species illustrate the abundance of female infertility in captive populations. In infertile rhinoceroses, oocyte collection and embryo production could represent the best remaining option for these animals to reproduce and to contribute to the genetic pool. We report here on superstimulation, repeated oocyte recovery, and attempted in vitro fertilization (IVF) in white and black rhinoceroses. Four anestrous rhinoceroses (two white, two black) with unknown follicular status were treated with gonadotropin-releasing hormone analogue, deslorelin acetate, for 6 to 7 d. Number and size of follicles in superstimulated females was significantly higher and larger compared with those in nonstimulated anestrous females (n=9). Ovum pick-up was achieved by transrectal ultrasound-guided follicle aspiration. Up to 15 follicles were aspirated per ovary. During six ovum pick-ups, a total of 29 cumulus-oocyte complexes (COCs) were harvested with a range of 2 to 9 COCs per collection. No postsurgical complications were noted on the rhinoceros ovaries using this minimally invasive approach. Various in vitro maturation (IVM) and IVF protocols were tested on the collected COCs. Despite the low total number of COCs available for IVM and IVF in this study, we can report the first rhinoceros embryo ever produced in vitro. The production of a 4-cell embryo demonstrated the potential of transrectal ultrasound-guided oocyte recovery as a valuable tool for in vitro production of rhinoceros embryos from otherwise infertile females.

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.

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

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.

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 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).

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.

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.

Antibiotic prophylaxis (AP) and mechanical bowel preparation (MBP) previous to surgery have classically been regarded as important in colorectal surgery. The latter has recently been questioned. We evaluated opinion of Spanish surgeons about the use of these measures.

E-mail survey among all members of Spanish Coloproctologic Associations.

Of 413 participants in the survey, 131 (31.7%) responded; 87% of surgeons used cathartics (70%), enemas (2%) or both (28%) for MBP. MBP was used 60% in right colon surgery, 90% in left colon and 99% in rectal surgery. Surgeons with more case load or those who specialized in colorectal surgery used significantly less MBP; 60% of the surgeons thought that MBP made surgery easier and reduced contamination; 35% thought that it decreased wound infection (WI) and 17% thought that it prevented anastomotic leaks. For 77%, it was regarded as useful or very useful. AP was used by 99.3% of surgeons including systemic alone in 86.2% and combined with oral in 16.8%. The first dose was given 2 h before surgery by 20.2% of the surgeons, at the anaesthetic induction by 78.3% and postoperatively by 1.5%; 43% used single dose only, 44.5% extended to 24 h and 12.5% for two or more days; 95% thought that AP reduced WI and 96% considered that it was useful.

There is general agreement on AP. MBP remained a common practice among Spanish colorectal surgeons except for right colonic resection. Surgeons with more case load and specialization used it significantly less.

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 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.

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.

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.

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.

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.

Nosocomial infections are the most frequent complications of surgical patients. Most surgical site infections (SSI) are acquired intraoperatively and arise from the flora of the patient's skin, gastrointestinal tract, or mucous membranes. Although preoperative mechanical cleansing of the bowel is considered by many surgeons a cornerstone of modern elective colorectal surgery and, in association with antibiotic prophylaxis, a fundamental component of an intestinal antisepsis program, many surgeons do not perform preoperative mechanical preparation routinely.

Review of the pertinent literature.

Some recent randomized trials and a Cochrane review found no proof that mechanical bowel preparation reduces the risk of complications after elective colorectal surgery. Indeed, there is some evidence that this intervention is associated with a higher rate of anastomotic leakage and wound complications.

The dogma that mechanical bowel preparation is necessary before elective colorectal surgery may need to be reconsidered. On the other hand, such preparation decreases operating time by improving bowel handling during construction of the anastomosis. Moreover, it is helpful when intestinal palpation will be necessary for identification of a lesion.

To compare the effectiveness, patient acceptability, and physical tolerability of two oral lavage solutions prior to colonoscopy in a Taiwanese population.

Eighty consecutive patients were randomized to receive either standard 4 L of polyethylene glycol (PEG) or 90 mL of sodium phosphate (NaP) in a split regimen of two 45 mL doses separated by 12 h, prior to colonoscopic evaluation. The primary endpoint was the percent of subjects who had completed the preparation. Secondary endpoints included colonic cleansing evaluated with an overall assessment and segmental evaluation, the tolerance and acceptability assessed by a self-administered structured questionnaire, and a safety profile such as any unexpected adverse events, electrolyte tests, physical exams, vital signs, and body weights.

A significantly higher completion rate was found in the NaP group compared to the PEG group (84.2% vs 27.5%, P<0.001). The amount of fluid suctioned was significantly less in patients taking NaP vs PEG (50.13+/-54.8 cc vs 121.13+/-115.4 cc, P<0.001), even after controlling for completion of the oral solution (P = 0.031). The two groups showed a comparable overall assessment of bowel preparation with a rate of "good" or "excellent" in 78.9% of patients in the NaP group and 82.5% in PEG group (P = 0.778). Patients taking NaP tended to have significantly better colonic segmental cleansing relative to stool amount observed in the descending (94.7% vs 70%, P = 0.007) and transverse (94.6% vs 74.4%, P = 0.025) colon. Slightly more patients graded the taste of NaP as "good" or "very good" compared to the PEG patients (32.5% vs 12.5%; P = 0.059). Patients' willingness to take the same preparation in the future was 68.4% in the NaP compared to 75% in the PEG group (P = 0.617). There was a significant increase in serum sodium and a significant decrease in phosphate and chloride levels in NaP group on the day following the colonoscopy without any clinical sequelae. Prolonged (>24 h) hemodynamic changes were also observed in 20-35% subjects of either group.

Both bowel cleansing agents proved to be similar in safety and effectiveness, while NaP appeared to be more cost-effective. After identifying and excluding patients with potential risk factors, sodium phosphate should become an alternative preparation for patients undergoing elective colonoscopy in the Taiwanese population.

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.

Bowel preparation is an established practice before abdominal surgery. Most surgeons would use both antibiotic prophylaxis and mechanical bowel preparation (MBP) before bowel surgery. In the literature, however, there is no evidence to support the use of MBP before elective colorectal surgery. Some randomized studies and a meta-analysis report a significantly higher incidence of wound infection in patients receiving MBP versus no bowel preparation. As to gynecological surgery, data are scanty, and there is a single randomized study reporting no advantage of MBP over no bowel preparation. Based on these evidences, the routine use of MBP should be reconsidered both in general and gynecological surgery.

To assess whether elective colon and rectal surgery can be safely performed without preoperative mechanical bowel preparation.

Mechanical bowel preparation is routinely done before colon and rectal surgery, aimed at reducing the risk of postoperative infectious complications. However, in cases of penetrating colon trauma, primary colonic anastomosis has proven to be safe even though the bowel is not prepared.

Patients undergoing elective colon and rectal resections with primary anastomosis were prospectively randomized into two groups. Group A had mechanical bowel preparation with polyethylene glycol before surgery, and group B had their surgery without preoperative mechanical bowel preparation. Patients were followed up for 30 days for wound, anastomotic, and intra-abdominal infectious complications.

Three hundred eighty patients were included in the study, 187 in group A and 193 in group B. Demographic characteristics, indications for surgery, and type of surgical procedure did not significantly differ between the two groups. Colo-colonic or colorectal anastomosis was performed in 63% of the patients in group A and 66% in group B. There was no difference in the rate of surgical infectious complications between the two groups. The overall infectious complications rate was 10.2% in group A and 8.8% in group B. Wound infection, anastomotic leak, and intra-abdominal abscess occurred in 6.4%, 3.7%, and 1.1% versus 5.7%, 2.1%, and 1%, respectively.

These results suggest that elective colon and rectal surgery may be safely performed without mechanical preparation.

The aim of this study was to assess recent literature regarding bowel preparation for colonoscopy and surgery.

The study was conducted by an Index Medicus English-language search of articles relevant to both oral mechanical and parenteral and oral antibiotic preparation for elective colorectal surgery and mechanical bowel preparation for colonoscopy. The study period was from 1975 to 2000. In addition, studies of elective colorectal surgery without mechanical bowel preparation were also considered.

Although several recent prospective, randomized trials have suggested that elective colorectal surgery can be safely performed without any mechanical bowel preparation, mechanical bowel preparation remains the standard of care, at least in North America at the present time. A recent survey of the members of The American Society of Colon and Rectal Surgeons revealed that the majority currently use sodium phosphate for bowel preparation and use a dual oral antibiotic regimen before elective colorectal surgery, combined with two doses of parenteral antibiotics. Although some of the use patterns are based on prospective, randomized study, others seem founded strictly on habit and theory.

The current methods of bowel cleansing for both colonoscopy and surgery include sodium phosphate and polyethylene glycol; colorectal surgeons practicing in North America currently prefer sodium phosphate. Additional preparation for colorectal surgery includes perioperative parenteral antibiotics and, to a slightly lesser degree, preoperative oral antibiotic preparation. Although some recent prospective, randomized studies have suggested that omission of mechanical bowel preparation for elective colorectal surgery is not only feasible but potentially preferable, caution is recommended before routinely omitting these widely practiced measures, because data to support such routine omission are limited.

Constipation is a common symptom that may be idiopathic or due to various identifiable disease processes. Laxatives are agents that add bulk to intestinal contents, that retain water within the bowel lumen by virtue of osmotic effects, or that stimulate intestinal secretion or motility, thereby increasing the frequency and ease of defecation. Drugs which improve constipation by stimulating gastrointestinal motility by direct actions on the enteric nervous system are under development. Other modalities used to treat constipation include biofeedback and surgery. Laxatives and lavage solutions are also used for colon preparation and evacuation of the bowels after toxic ingestions.

Efficient mechanical bowel preparation has been regarded as essential in preventing postoperative complications of colorectal surgery, but the necessity of bowel cleansing has been disputed recently. The aim of this study was to evaluate the outcome of elective colorectal surgery in patients with or without bowel preparation.

Altogether, 267 consecutive adult patients admitted for elective open colorectal surgery were randomly assigned either to the bowel preparation group with oral polyethylene glycol electrolyte solution (138 patients) or no preparation group (129 patients). Patients who were unable to drink polyethylene glycol electrolyte solution, those who had had bowel preparation within the previous week, and patients not needing opening of the bowel were excluded. Routine colorectal surgery was undertaken, and infectious and other complications were registered daily. Late complications were checked up one to two months after surgery.

No deaths were recorded, and 76 percent of the patients in the polyethylene glycol electrolyte solution group and 81 percent in the unprepared group recovered without complication. Anastomotic leaks occurred in 4 percent of the polyethylene glycol electrolyte solution patients and in 2 percent of the other cases, and other surgical site infections occurred in 6 and 5 percent, respectively. None of the differences was statistically significant. There was no difference in restoration of bowel function. The median postoperative stay was eight days in both groups.

Preoperative bowel preparation seems to offer no benefit in elective open colorectal surgery.

Laxatives and lavage solutions are used in the treatment of constipation and toxic ingestion and also for preparation of the colon before endoscopic or surgical procedures. Several different categories of agents are available for use. These include bulking agents, osmotic agents, secretagogues and agents with direct effects on epithelial nerve or smooth muscle cells, and lubricating agents. Each category has different pharmacologic effects, side effects, and clinical indications. This review summarizes current information about these agents.

The aim of this study was to compare the cleansing ability, patient compliance, and safety of two oral solutions for elective colorectal surgery.

All eligible patients were prospectively randomized to receive either 4 l of standard polyethylene glycol (PEG) solution or 90 ml of sodium phosphate (NaP) as mechanical bowel preparation for colorectal surgery. A detailed questionnaire was used to assess patient compliance. In addition, the surgeons, blinded to the preparation, intraoperatively evaluated its quality. Postoperative septic complications were also assessed. The calcium serum level was monitored before and after bowel preparation. Statistical analysis was performed using the Wilcoxon's rank-sum test and Fisher's exact test.

Two hundred patients, well matched for age, gender, and diagnosis, were prospectively randomized to receive either PEG or NaP solutions for elective colorectal surgery. All patients completed all phases of the trial. There was a significant decrease in serum calcium levels after administration of both NaP (mean, 9.3-8.8 mg/dl) and PEG (9.2-8.9 mg/dl), respectively (P < 0.0001), with no clinical sequelae. However, patient tolerance to NaP was superior to PEG: less trouble drinking the preparation (17 vs. 32 percent; P < 0.0002), less abdominal pain (12 vs. 22 percent; P = 0.004), less bloating (7 vs. 28 percent), and less fatigue (8 vs. 17 percent), respectively. Additionally, 65 percent of patients who received the NaP preparation stated they would repeat this preparation again compared with only 25 percent for the PEG group (P < 0.0001). Ninety-five percent of patients who received the NaP solution tolerated 100 percent of the solution compared with only 37 percent of the PEG group (P < 0.0001). For quality of cleansing, surgeons scored NaP as "excellent" or "good" in 87 compared with 76 percent after PEG (P = not significant). Rates of septic and anastomotic complications were 1 percent and 1 percent for NaP and 4 percent and 1 percent for PEG, respectively (P = not significant).

Both oral solutions proved to be equally effective and safe. However, patient tolerance of the small volume of NaP demonstrated a clear advantage over the traditional PEG solution.

A survey was conducted to document current perioperative steroid use in colorectal patients.

A mail survey was sent to 1,400 members and fellows of The American Society of Colon and Rectal Surgeons.

Three hundred seven questionnaires (21.9 percent) were returned. Twenty-four respondents had retired or lacked accurate data. The remaining 283 surgeons averaged 43.5 (range, 31-71) years in age and had been in practice an average of 11 (range, 1-39) years. Ninety-seven percent were certified by the American Board of Surgery, 87 percent by the American Board of Colon and Rectal Surgery, and 85 percent by both. Eighty-six percent of respondents manage the perioperative steroids and 85 percent manage the postoperative steroid taper of their patients. In patients receiving preoperative steroids, 84 percent of respondents administer 100 mg of hydrocortisone phosphate intravenously before surgery. The most common postoperative dosage (used by 62 percent) was 100 mg of hydrocortisone phosphate intravenously every eight hours, which was tapered to 50 mg intravenously every 8 to 12 hours. Most patients (49 percent) received 20 mg of prednisone per day when their oral intake was resumed. The most common taper regimen was a 5 mg reduction per week (61 percent of respondents).

Despite lack of scientifically established requirements or proven physiologic guidelines, perioperative steroid use by colorectal surgeons appears relatively consistent.

The purpose of this article was to review the prognostic factors of significance in rectal cancer.

This is a retrospective review of various reports and an examination of our data.

Current imaging techniques with endorectal ultrasound, magnetic resonance imaging with a rectal probe, and possibly tagged monoclonal antibodies allow for presurgical assessment of the invasion of the rectal wall and detection of lymph node involvement.

Tumor penetration of the rectal wall and lymph node metastases are the most important prognostic indicators in rectal cancer and predict local and distant recurrences. When lymph node metastases occur, they are more common in small lymph nodes (< 5 mm). Patients with lymph node metastases always need to be considered for multimodality therapy. Tumors larger than or equal to T3 or with associated lymph node metastases should not be treated with sphincter-saving surgical procedures alone.

Intraoperative rectal washout reduces rectal bacterial flora concentration and exfoliated tumor cells but compromises operating theater sterility. I present the Colo-Shower (Sapi-Med, Alessandria, Italy), a modified, disposable proctoscope for intraoperative rectal irrigation that, by collecting liquid flowing out of the anus during rectal washout, minimizes operating theater pollution. The Colo-Shower, which has now been used on 100 patients who underwent ileorectal or colorectal anastomosis, is effective and easy to use.