Current practice patterns of preoperative bowel preparation in colorectal surgery: a nation-wide survey by the Chinese Society of Colorectal Cancer

Is mechanical bowel preparation mandatory for elective colon surgery? A systematic review and meta-analysis

BACKGROUND

Growing evidence demonstrates minimal impact of mechanical bowel preparation (MBP) on reducing postoperative complications following elective colectomy. This study investigated the necessity of MBP prior to elective colonic resection.

METHOD

A systematic literature review was conducted across PubMed, Ovid, and the Cochrane Library to identify studies comparing the effects of MBP with no preparation before elective colectomy, up until May 26, 2023. Surgical-related outcomes were compiled and subsequently analyzed. The primary outcomes included the incidence of anastomosis leakage (AL) and surgical site infection (SSI), analyzed using Review Manager Software (v 5.3).

RESULTS

The analysis included 14 studies, comprising seven RCTs with 5146 participants. Demographic information was consistent across groups. No significant differences were found between the groups in terms of AL ((P = 0.43, OR = 1.16, 95% CI (0.80, 1.68), I2 = 0%) or SSI (P = 0.47, OR = 1.20, 95% CI (0.73, 1.96), I2 = 0%), nor were there significant differences in other outcomes. Subgroup analysis on oral antibiotic use showed no significant changes in results. However, in cases of right colectomy, the group without preparation showed a significantly lower incidence of SSI (P = 0.01, OR = 0.52, 95% CI (0.31, 0.86), I2 = 1%). No significant differences were found in other subgroup analyses.

CONCLUSION

The current evidence robustly indicates that MBP before elective colectomy does not confer significant benefits in reducing postoperative complications. Therefore, it is justified to forego MBP prior to elective colectomy, irrespective of tumor location.

Short-term and long-term outcomes of intracorporeal anastomosis in laparoscopic segmental left colectomy for splenic flexure cancer - a multicenter retrospective cohort study of 342 cases

INTRODUCTION

While intracorporeal anastomosis (IA) has been widely used in totally laparoscopic right colectomy, its application in laparoscopic segmental left colectomy for splenic flexure cancer remains underexplored, particularly in large-scale studies with long-term outcomes. This research aims to assess the technical feasibility and oncological efficacy of IA in treating colonic splenic flexure carcinoma, drawing insights from both short-term and long-term outcomes of a retrospective cohort.

MATERIALS AND METHODS

A retrospective analysis was conducted on 342 patients diagnosed with colonic splenic flexure carcinoma in three Chinese medical centers. These patients underwent laparoscopic segmental left colectomy between December 2014 and December 2019 across three medical institutions. Comprehensive data encompassing demographics, disease features, pathological characteristics, operative details, and both short-term and long-term outcomes were gathered and scrutinized. Using propensity scores, each patient from the IA cohort was paired with a counterpart from the extracorporeal anastomosis (EA) cohort.

RESULTS

IA was performed on 129 patients, while 213 underwent EA. Post-propensity score matching resulted in 129 matched pairs. After matching, many baseline characteristics were balanced. The IA cohort exhibited several advantages, including shorter incision lengths ( P <0.001) and more extensive proximal and distal resection margins ( P =0.003, P <0.001). Additionally, the IA method facilitated a more rapid postoperative recovery as indicated by quicker return of bowel movements (resumption of passing flatus [2.7 (1.0-7.0) days vs. 3.3 (2.0-8.0) days, P <0.001] and defecation [3.7 (1.0-9.0)] days vs. 4.5 (2.0-9.0) days, P <0.001]), faster discharges [6.6 (3.0-15.0) days vs. 8.3 (5.0-20.0) days, P <0.001], and decreased need for rescue analgesics ( P <0.001). The rate of postoperative complications, as rated by the Clavien-Dindo classification, remained consistent across both techniques ( P =0.087). Furthermore, the cosmetic outcome rated by Patient Scar Assessment Questionnaire and Scoring System (PSAQ) was markedly superior in the IA group ( P <0.001). Both approaches demonstrated equivalent 5-year overall (82.7% vs. 82.1%, P =0.419) and disease-free survival (80.9% vs. 78.1%, P =0.476). Subsequent stratification analysis revealed that IA achieved comparable 5-year overall (80.7% vs. 82.0%, P =0.647) and disease-free survival (78.1% vs. 76.4%, P =0.734) in patients with locally advanced colon cancer.

CONCLUSION

Employing IA for laparoscopic segmental left colectomy in cases of splenic flexure carcinoma is not only safe but also offers enhanced cosmetic results and expedited postoperative recovery. Oncologically speaking, IA in left segmental colectomy for splenic flexure carcinoma can yield therapeutic outcomes comparable to those of EA, even in patients with locally advanced colon cancer.

The role of preoperative mechanical bowel preparation and oral antibiotics in prevention of anastomotic leakage following restorative resection for primary rectal cancer - a systematic review and meta-analysis

PURPOSE

Anastomotic leakage after colorectal cancer resection is a feared postoperative complication seen among up till 10-20% of patients, with a higher risk following rectal resection than colon resection. Recent studies suggest that the combined use of preoperative mechanical bowel preparation and oral antibiotics may have a preventive effect on anastomotic leakage. This systematic review aims to explore the association between preoperative mechanical bowel preparation combined with oral antibiotics and the risk of anastomotic leakage following restorative resection for primary rectal cancer.

METHODS

Three databases were systematically searched in February 2022. Studies reporting anastomotic leakage rate in patients, who received mechanical bowel preparation and oral antibiotics before elective restorative resection for primary rectal cancer, were included. A meta-analysis was conducted based on the risk ratios of anastomotic leakage.

RESULTS

Among 839 studies, 5 studies met the eligibility criteria. The median number of patients were 6111 (80-29,739). The combination of preoperative mechanical bowel preparation and oral antibiotics was associated with a decreased risk of anastomotic leakage (risk ratio = 0.52 (95% confidence interval 0.39-0.69), p-value < 0.001). Limitations included a low number of studies, small sample sizes and the studies being rather heterogenous.

CONCLUSION

This systematic review and meta-analysis found that the use of mechanical bowel preparation and oral antibiotics is associated with a decreased risk of anastomotic leakage among patients undergoing restorative resection for primary rectal cancer. The limitations of the review should be taken into consideration when interpreting the results.

Preparing the Bowel (Microbiome) for Surgery: Surgical Bioresilience

The preparation of the bowel for radical surgery is a corner stone of elective colorectal practice. The evidence for this intervention is of variable quality and it is often contradictory, yet there is now a global move toward the adoption of oral antibiotic therapy for the reduction of perioperative infective complications, such as surgical site infections. The gut microbiome is a critical mediator of the systemic inflammatory response to surgical injury, wound healing, and perioperative gut function. The loss of critical microbial symbiotic functions caused by bowel preparation and surgery has an adverse impact on surgical outcomes, yet the mechanisms through which this occurs are poorly defined. In this review, the evidence for bowel preparation strategies is critically appraised in the context of the gut microbiome. The impact of antibiotic therapy on the surgical gut microbiome and the importance of the intestinal "resistome" to surgical recovery is described. Data to support the augmentation of the microbiome through diet, probiotic and symbiotic approaches, as well as fecal transplantation are also appraised. Finally, we propose a novel strategy of bowel preparation defined as " surgical bioresilience " and define areas or prioritization in this emerging field. This describes the optimization of surgical intestinal homeostasis and core surgical exposome-microbiome interactions that regulate the wound immune microenvironment, the systemic inflammatory response to surgical injury, and gut function across the perioperative time course.

Impact of bowel preparation on elective colectomies for diverticulitis: analysis of the NSQIP database

BACKGROUND

Recent data based on large databases show that bowel preparation (BP) is associated with improved outcomes in patients undergoing elective colorectal surgery. However, it remains unclear whether BP in elective colectomies would lead to similar results in patients with diverticulitis. The purpose of this study was to investigate whether bowel preparation affected the surgical site infections (SSI) and anastomotic leakage (AL) in patients with diverticulitis undergoing elective colectomies.

STUDY DESIGN

We identified 16,380 diverticulitis patients who underwent elective colectomies from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) colectomy targeted database (2012-2017). Multivariate logistic regression models were employed to investigate the impact of different bowel preparation strategies on postoperative complications, including SSI and AL.

RESULTS

In the identified population, a total of 2524 patients (15.4%) received no preparation (NP), 4715 (28.8%) mechanical bowel preparation (MBP) alone, 739 (4.5%) antibiotic bowel preparation (ABP) alone, and 8402 (51.3%) MBP + ABP. Compared to NP, patients who received any type of bowel preparations showed a significantly decreased risk of SSI and AL after adjustment for potential confounders (SSI: MBP [OR = 0.82, 95%CI: 0.70-0.96], ABP [0.69, 95%CI: 0.52-0.92]; AL: MBP [OR = 0.66, 95%CI: 0.51-0.86], ABP [0.56, 95%CI: 0.34-0.93]), where the combination type of MBP + ABP had the strongest effect (SSI:OR = 0.58, 95%CI:0.50-0.67; AL:OR = 0.46, 95%CI:0.36-0.59). The significantly decreased risk of 30-day mortality was observed in the bowel preparation of MBP + ABP only (OR = 0.32, 95%CI: 0.13-0.79). After the further stratification by surgery procedures, patients who received MBP + ABP showed consistently lower risk for both SSI and AL when undergoing open and laparoscopic surgeries (Open: SSI [OR = 0.51, 95%CI: 0.37-0.69], AL [OR = 0.47, 95%CI: 0.25-0.91]; Laparoscopic: SSI [OR = 0.58, 95%CI: 0.47-0.72, AL [OR = 0.49, 95%CI: 0.35-0.68]).

CONCLUSIONS

MBP + ABP for diverticulitis patients undergoing elective open or laparoscopic colectomies was associated with decreased risk of SSI, AL, and 30-day mortality. Benefits of MBP + ABP for diverticulitis patients underwent robotic surgeries warrant further investigation.

Updates of Risk Factors for Anastomotic Leakage after Colorectal Surgery

Anastomotic leakage is a potentially severe complication occurring after colorectal surgery and can lead to increased morbidity and mortality, permanent stoma formation, and cancer recurrence. Multiple risk factors for anastomotic leak have been identified, and these can allow for better prevention and an earlier diagnosis of this significant complication. There are nonmodifiable factors such as male gender, comorbidities and distance of tumor from anal verge, and modifiable risk factors, including smoking and alcohol consumption, obesity, preoperative radiotherapy and preoperative use of steroids or non-steroidal anti-inflammatory drugs. Perioperative blood transfusion was shown to be an important risk factor for anastomotic failure. Recent studies on the laparoscopic approach in colorectal surgery found no statistical difference in anastomotic leakage rate compared with open surgery. A diverting stoma at the time of primary surgery does not appear to reduce the leak rate but may reduce its clinical consequences and the need for additional surgery if anastomotic leakage does occur. It is still debatable if preoperative bowel preparation should be used, especially for left colon and rectal resections, but studies have shown similar incidence of postoperative leak rate.

Male Patients may be More Vulnerable to Acute Kidney Injury After Colorectal Surgery in an Enhanced Recovery Program: A Propensity Score Matching Analysis

BACKGROUND

Although many reports have shown that enhanced recovery after surgery (ERAS) programs improve the perioperative outcomes of patients undergoing colorectal surgery, the prevalence of early acute kidney injury (AKI) after surgery in such patients requires attention. Protective roles of the female sex in terms of chronic kidney disease and progression of ischemic renal injury have been described in many studies. We thus explored whether a sex difference was evident in terms of postoperative AKI in a colorectal ERAS setting.

METHODS

From January 2017 to August 2019, 453 patients underwent laparoscopic colorectal cancer resection in an enhanced recovery program. Of these, 217 female patients were propensity score (PS)-matched with 236 male patients. Then, 215 patients of either sex were compared in terms of postoperative renal function and complications.

RESULTS

Among the PS-matched patients, the incidence of AKI was significantly higher in male than female patients (24.2% vs. 9.8%, P < 0.001). Male patients also exhibited a greater reduction in the postoperative estimated glomerular filtration rate, compared with female patients. The male sex was associated with an approximately threefold increase in the risk of AKI. The rate of surgical complications was significantly higher in male than female patients.

CONCLUSIONS

Caution must be taken to prevent postoperative AKI in patients (particularly males) participating in colorectal ERAS programs. The mechanism underlying the sex difference remains unclear. Additional studies are required to determine whether male patients require perioperative management that differs from that of females, to prevent postoperative AKI.

Controversies in preoperative bowel preparation in gynecologic and gynecologic oncology surgery: a review of the literature

PURPOSE

The purpose of this review is to assess the impact of mechanical and oral antibiotics bowel preparation on surgical performance and to investigate their role before gynecologic surgical procedures regarding the infection rates. We also aim to study the updated evidence regarding the use of these different types of bowel preparation, as well as the current preoperative practice applied.

METHODS

An extensive search of the literature was conducted with Medline/PubMed, and the Cochrane Library Database of Systematic Reviews being used for our primary search.

RESULTS

To date, due to the conflicting guidelines by the scientific societies, surgeons do not use a specific pattern of bowel preparation regimen. There are no strong evidence supporting mechanical bowel preparation, but instead, in many cases, patients' adverse effects, both physiological and psychological have been noted. On the other hand, the combined use of oral antibiotic and mechanical bowel preparation has been proven beneficial in colorectal surgery in reducing postoperative morbidities.

CONCLUSION

Based on current literature, in gynecologic surgeries with minimal probability of intraluminal entry, a regimen without any bowel preparation should be applied. The combined administration of both mechanical and oral antibiotic bowel preparation, or even the use of the oral antibiotics alone, should be preserved for cases of increased complexity, where bowel involvement is highly anticipated, such as in gynecologic oncology, as stated in the ERAS protocols. Nonetheless, further research specific to gynecologic surgery is required.

Impact of intraoperative zero-balance fluid therapy on the occurrence of acute kidney injury in patients who had undergone colorectal cancer resection within an enhanced recovery after surgery protocol: a propensity score matching analysis

PURPOSE

An enhanced recovery after surgery (ERAS) protocol for colorectal cancer resection encourages perioperative euvolemic status, and zero-balance fluid therapy is recommended for low-risk patients. Recently, several studies have reported concerns of increased acute kidney injury (AKI) in patients within an ERAS protocol. In the present study, we investigated the impact of intraoperative zero-balance fluid therapy within an ERAS protocol on postoperative AKI.

METHODS

Patients who underwent elective surgery for primary colorectal cancer were divided into zero-balance and non-zero-balance fluid therapy groups according to intraoperative fluid amount and balance. After propensity score (PS) matching, 210 patients from each group were selected. Incidences of AKI were compared between the two groups according to the Kidney Disease Improving Global Outcomes criteria. Postoperative kidney functions and surgical outcomes were also compared.

RESULTS

AKI was significantly higher in the zero-balance fluid therapy group compared to the non-zero-balance fluid therapy group (21.4% vs. 13.8%, p = 0.040) in PS-matched patients. The decrease in the estimated glomerular filtration rate on the day of surgery was significantly higher in the zero-balance fluid therapy group (- 5.9 mL/min/1.73 m² vs. - 1.4 mL/min/1.73 m², p = 0.005). There were no differences in general morbidity or mortality rate, although surgery-related complications were more common in the zero-balance group.

CONCLUSIONS

Despite the proven benefits of zero-balance fluid therapy in colorectal ERAS protocols, care should be taken to monitor for postoperative AKI. Further studies regarding the clinical significance of postoperative AKI occurrence and optimised intraoperative fluid therapy are needed in a colorectal ERAS setting.

Preoperative Bowel Preparation in Minimally Invasive and Vaginal Gynecologic Surgery

Bowel preparation traditionally refers to the removal of bowel contents via mechanical cleansing measures. Although it has been a common practice for more than 70 years, its use is based mostly on expert opinion rather than solid evidence. Mechanical bowel preparation in minimally invasive and vaginal gynecologic surgery is strongly debated, since many studies have not confirmed its effectiveness, neither in reducing postoperative infectious morbidity nor in improving surgeons' performance. A comprehensive search of Medline/PubMed and the Cochrane Library Database was conducted, for related articles up to June 2019, including terms such as "mechanical bowel preparation," "vaginal surgery," "minimally invasive," and "gynecology." We aimed to determine the best practice regarding bowel preparation before these surgical approaches. In previous studies, bowel preparation was evaluated only via mechanical measures. The identified randomized trials in laparoscopic approach and in vaginal surgery were 8 and 4, respectively. Most of them compare different types of preparation, with patients being separated into groups of oral laxatives, rectal measures (enema), low residue diet, and fasting. The outcomes of interest are the quality of the surgical field, postoperative infectious complications, length of hospital stay, and patients' comfort during the whole procedure. The results are almost identical regardless of the procedure's type. Routine administration of bowel preparation seems to offer no advantage to any of the objectives mentioned above. Taking into consideration the fact that in most gynecologic cases there is minimal probability of bowel intraluminal entry and, thus, low surgical site infection rates, most scientific societies have issued guidelines against the use of any bowel preparation regimen before laparoscopic or vaginal surgery. Nonetheless, surgeons still do not use a specific pattern and continue ordering them. However, according to recent evidence, preoperative bowel preparation of any type should be omitted prior to minimally invasive and vaginal gynecologic surgeries.

The Role of Bowel Preparation in Open, Minimally Invasive, and Converted-to-Open Colectomy

BACKGROUND

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.

METHODS

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).

RESULTS

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.

CONCLUSIONS

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