Complications after colorectal surgery without mechanical bowel preparation

BACKGROUND: The current practice of mechanical bowel preparation (MBP) before colorectal surgery is questionable. Mechanical bowel preparation is unpleasant for the patient, often distressful, and potentially harmful. The results are often less than desired, increasing the risk of contamination. Cleansing the colon and rectum before surgery has never been shown in clinical trials to benefit patients. In animal experiments MBP has a detrimental effect on colonic healing. STUDY DESIGN: To investigate the outcomes of colorectal surgery without MBP, we prospectively evaluated a consecutive series of patients who underwent resection and primary anastomosis of the colon and upper rectum, including emergency operations. One surgeon performed all operations. Endpoints were wound infection, anastomotic failure, and death. Late signs and symptoms that might be secondary to leakage of the anastomosis were considered as an anastomotic failure as well, during a followup of 1 year. RESULTS: Two hundred fifty operations were performed, of which 199 (79.6%) were elective. Colectomies were left-sided in 65.6%. Anastomoses were ileocolic in 32%, colocolic in 20.8%, colorectal intraperitoneal in 34.4%, and extraperitoneal in 12.8%. No patient suffered from fecal impaction. Followup was complete in 97.2%. Eight patients (3.3%; 95% confidence interval [CI]: 1.4-6.4) developed superficial wound infections. In three patients there was leakage from an extraperitoneal colorectal anastomosis, in two of them after hospital discharge. The overall anastomotic failure rate was 1.2% (95% CI: 0.3-3.6). The in-hospital mortality rate was 0.8% (95% CI: 0.1-2.9) and was not related to abdominal or septic complications. CONCLUSION: Mechanical bowel preparation is not a sine qua non for safe colorectal surgery.     

结直肠切除术前常规机械性肠道准备随机对照研究的系统评价

目的 明确结肠、直肠切除吻合术前常规机械性肠道准备（mechanical bowel preparation, MBP）的安全性和有效性。方法 检索2008年1月以前MEDLINE、EMBASE、Cochrane Library、Cochrane协作网随机对照试验注册数据库、中国期刊全文数据库（CNKI）等数据库,纳入相关随机对照试验进行系统评价和Meta分析。结果 纳入12个随机对照试验共4992例结肠、直肠切除吻合病例。分析发现,MBP组与无MBP组在病死率［RR为1.02,95%CI （0.64,1.59）,P=0.95］、吻合口漏发生率［RR值为1.16,95%CI（0.86,1.55）,P=0.33］、再手术率［RR值为1.05,95%CI（0.81,1.35）,P=0.71］、切口感染率［RR值为1.17,95%CI （0.98,1.40）,P=0.08］和腹腔脓肿发生率［RR值为0.93,95%CI（0.60,1.45）,P=0.75］等方面的差异无统计学意义。结论 结肠、直肠切除吻合术前无需常规进行机械性肠道准备。     

Colon and rectal surgery without mechanical bowel preparation: a randomized prospective trial

OBJECTIVE: To assess whether elective colon and rectal surgery can be safely performed without preoperative mechanical bowel preparation. SUMMARY BACKGROUND DATA: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: These results suggest that elective colon and rectal surgery may be safely performed without mechanical preparation.     

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.     

Evaluation of morbidity and mortality after anastomotic leakage following elective colorectal surgery in patients treated with or without mechanical bowel preparation

Background

A previous multicenter randomized trial demonstrated that mechanical bowel preparation (MBP) does not guard against anastomotic leakage in elective colorectal surgery. The aim of this complementary study was to evaluate the effects of MBP on morbidity and mortality after anastomotic leakage in elective colorectal surgery.

Methods

A subgroup analysis was performed of a randomized trial comparing the incidence of anastomotic leakage and septic complications with and without MBP in patients undergoing elective colorectal surgery.

Results

Elective colorectal surgery was performed in 1,433 patients with primary anastomoses, of whom 63 patients developed anastomotic leakage. Twenty-eight patients (44%) received MBP and 35 patients (56%) did not. Mortality rate, initial need for surgical reintervention, and extent of bowel contamination did not differ between groups (29% vs 40%; P = .497, P = .667, and P = .998, respectively).

Conclusions

No benefit of MBP was found regarding morbidity and mortality after anastomotic leakage in elective colorectal surgery.     

选择性结直肠手术中机械性肠道准备的必要性

目的 分析机械性肠道准备在选择性结直肠外科手术中的必要性.方法 将77例行选择性结直肠手术的患者分为进行机械性肠道准备组(MBP组,42例)与未进行机械性肠道准备组(非MBP组,35例),分析两组术后吻合口瘘、感染等并发症发生的差异.结果 两组在术后吻合口瘘、切口感染、切口裂开等并发症发生方面无统计学差异(P＞0.05).结论 术前的MBP对降低选择性结直肠手术术后并发症方面没有显著的优势,术前MBP可能并非必要.     

Polyethylene glycol versus sodium phosphate mechanical bowel preparation in elective colorectal surgery

BACKGROUND: The type of mechanical bowel preparation (MBP) used before elective colorectal surgery remains controversial. METHODS: This post hoc analysis of a prospective randomized controlled antibiotic prophylaxis trial (ertapenem vs. cefotetan) evaluated the effect of polyethylene glycol (PEG) and sodium phosphate (SP) MBPs on the rates of postoperative surgical site infections (SSI). RESULTS: Good to excellent MBPs were observed in 281 of 303 (93%) evaluable patients for the PEG and 336 of 367 (92%) for the SP types. A higher rate of SSI was observed in the PEG (34%) than SP (24%) group (difference, 10%; 95% confidence interval, 3.4-17.2). The MBP type was a significant risk factor for SSI, with SP favored over PEG (odds ratio, .6; 95% confidence interval, .43-.85) in univariate analysis; multivariate analysis favored SP, but was not significant (odds ratio, .69; 95% confidence interval, .46-1.02). SSI was lowest with SP and ertapenem (19%) and highest with PEG and cefotetan (44%). CONCLUSIONS: SP, coupled with ertapenem antibiotic prophylaxis, may improve outcomes and reduce SSIs in patients undergoing elective colorectal surgery when compared with PEG coupled with cefotetan antibiotic prophylaxis.     

结直肠手术前磷酸钠盐一日肠道准备法临床观察

目的探讨结直肠术前1d肠道准备的安全性和可行性。方法将40例结直肠手术患者随机分为实验组和对照组,每组各20例,两组分别采用磷酸钠术前1d和硫酸镁术前3d肠道准备法;所有患者分别于肠道准备前后抽取外周静脉血检测血红蛋白、血细胞比容和血清部分离子水平,取粪做厌氧菌培养计数,并观察手术前后患者一般情况、手术并发症和肠道黏膜形态。结果两种肠道准备方法对患者的吻合口愈合及感染并发症均无明显影响,实验组患者对肠道准备耐受性明显优于对照组,手术前后的腹泻次数明显低于对照组;两组患者各项血液检验指标、肠道黏膜形态等没有明显差异;全部病例肠道准备后大便厌氧菌计数显著增加。结论磷酸钠术前1d准备法安全可靠,可替代传统的3d准备法;适当缩短肠道准备时间可降低患者的不适程度和术后菌群紊乱的发生,减轻肠屏障的损害。     

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).     

结直肠癌术前机械性肠道准备的可行性分析

目的探讨结直肠癌患者术前不实施机械性肠道准备（MBP）的可行性。 方法前瞻性选择2016年9月至2018年1月攀枝花市中心医院收治的结直肠癌患者104例,采用随机数字表法分为非机械性肠道准备组（non-MBP组）53例和机械性肠道准备组（MBP组）51例。观察两组术后并发症的发生和机体应激反应指标的变化。 结果两组术前的hs-CRP、IL-6、Cor水平差异无统计学意义;non-MBP组术后24、48 h时的IL-6、Cor及hs-CRP水平均显著低于同期MBP组,差异有统计学意义（均P<0.05）。监测术后30 d并发症,两组患者均未发生腹腔感染,吻合口漏、切口感染、术野冲洗液细菌培养、术后肠梗阻的发生率比较,差异无统计学意义。non-MBP组患者球杆菌比例失调、腹泻的发生率分别为7.5%（4/53）、5.6%（3/53）,显著低于MBP组的23.5%（12/51）、15.6%（8/51）,差异有统计学意义（χ²=4.367、8.341,P=0.037、0.009）。 结论术前MBP会加重结直肠癌患者术后机体的应激反应,结直肠癌择期手术术前可不行MBP,并不增加术后并发症的发生。     

A clinical and physiological evaluation of bowel preparation for elective colorectal surgery

Efficient mechanical bowel preparation is essential for satisfactory double-contrast barium enema and colonoscopy. Satisfactory mechanical preparation is also important for reducing the risk of anastomotic dehiscence and sepsis in elective colorectal surgery. Traditional mechanical preparation by fasting, purgation, and enemas is timeconsuming, unpleasant for patients and nursing staff, and in our center, results in a perfect preparation in only 23% of patients. Elemental diets are expensive and inefficient when used for only 5 days. Whole bowel irrigation involves the use of a nasogastric tube and provides a rapid preparation with a perfect result in 61% of patients, but is not recommended for patients with stenosing tumors. Furthermore, irrigation with saline causes sodium and water retention which may precipitate heart failure in the elderly unless preceded by furosemide. The use of a balanced electrolyte solution reduces the risk of these side effects. Recently, oral irrigation with mannitol has become popular, but in our experience, results in a perfect preparation in only 41% of patients unless followed by a short saline lavage (85% satisfactory). Mannitol also produces potentially explosive gas mixtures by bacterial fermentation unless oral antimicrobials (neomycin and metronidazole) are used immediately before operation. Therefore, we recommend mannitol, saline lavage, and antibiotics in most cases, but still find a place for traditional preparation over 5 days for patients with tumors associated with severe stenosis of the left colon.

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Résumé La préparation mécanique parfaite du colon est indispensable pour permettre l'exploration radiologique en double contraste et l'exploration endoscopique. Elle réduit également les risques de déhiscence de l'anastomose et de péritonite septique lors de la chirurgie colique.La préparation mécanique classique par le jeûne, la purge, les lavements fait perdre du temps, est déplaisante pour le malade et le personnel soignant et surtout ne donne un résultat parfait que dans 23% des cas. Les régimes alimentaires spécifiques sont onéreux et inefficaces, quand ils ne sont pas prolongés au delà de 5 jours.L'irrigation intestinale à l'aide d'un tube naso gastrique permet une préparation parfaite dans 61% des cas, mais elle ne saurait être pratiquée lorsque la lésion répond à une tumeur sténosante. En outre, l'irrigation avec une solution saline peut provoquer une rétention hydrique et sodique qui peut entraîner la défaillance cardiaque chez le sujet âgé. L'emploi d'une solution équilibrée en électrolytes peut réduire ces risques.L'irrigation avec le Mannitol, méthode plus récente, est devenue très populaire mais selon notre propre expérience, elle n'a assuré la préparation parfaite de l'intestin que dans 41% des cas à moins de lui associer un lavement salé le taux de résultats satisfaisants atteignant alors 85%. Le mannitol a pour inconvénient de produire un mélange de gaz explosifs du à la fermentation bactérienne, à moins que l'intestin ait été préparé immédiatement avant l'opération par des agents antimicrobiens absorbés par voie orale (néomycine et métronidazole).En conclusion, nous recommandons dans la majorité des cas la préparation qui associe mannitol, lavement salé et antibiotiques réservant la préparation classique pendant une période de 5 jours aux cas de tumeurs sténosantes du colon gauche.

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Presented at the XXIXth Congress of the Société Internationale de Chirurgie, Montreux, Switzerland, September, 1981.     

Meta-analysis of randomized, controlled clinical trials of antibiotic prophylaxis in biliary tract surgery

In this study all available clinical trials of antibiotic prophylaxis in biliary tract surgery, published from 1965 to 1988, were examined. Results of 42 randomized, controlled trials (4129 patients), in which a group of patients treated with antibiotics was compared with a group of patients not treated with antibiotics, were pooled. Wound infection rates in the control groups range from 3 to 47 per cent and are 15 per cent overall. The overall difference in infection rates is 9 per cent in favour of antibiotic treatment (95 per cent confidence interval 7-11 per cent), while the common odds ratio is 0.30 (95 per cent confidence interval 0.23-0.38). Subgroup meta-analysis showed a significant stronger protective effect in high risk patients, while the timing of wound inspection (i.e. early in hospital or late at follow-up) markedly influenced the treatment effect reported. Comparison of wound infection rates in patients treated with first generation versus second or third generation cephalosporins (11 trials, 1128 patients), as well as single-dose versus multiple-dose regimens (15 trials, 1226 patients) did not reveal any significant effect (P greater than 0.05) in each trial separately as well as in the overall comparison. The results indicate that there is evidence against further use of no-treatment controls and that the choice of treatment regimen can largely be made on the basis of cost.