D. C. N. K. Nyam

Transanal approach to rectocele repair may compromise anal sphincter pressures

PURPOSE: This study prospectively assessed the functional results, particularly anal sphincter impairment, following transanal repair of rectocele for chronic intractable constipation. METHOD: Twenty-one consecutive women (mean age, 47.7 (standard error of the mean, 2.7) years) had the diagnosis of rectocele obstructing defecation made on synchronized anal manometry, electromyography, and cinedefecography. All underwent a standardized transanal repair with controlled anal stretching (maximum of 4 cm) from self-retaining anal retractors. The clinical function and anorectal manometry were assessed before surgery and were repeated six months later. RESULTS: All 21 patients were subjectively satisfied with the relief from constipation after surgery. There were significant improvements in the straining at defecation (before, n=19; after, n=3;P=0.001), need to digitate per vagina (before, n=16; after, n=0;P=0.001), stool frequency (before, 3.8 (0.7) times weekly; after, 8.6 (1.2);P=0.004), and laxative requirements (before, n=7; after, n=0;P=0.03). Although none were clinically incontinent, there was a mean 28 mmHg impairment in resting (P<0.05) and 42.6 mmHg impairment in maximum squeeze anal pressures (P<0.05) after operations. There was no other morbidity. CONCLUSION: Transanal rectocele repair effectively improves constipation problems, at the risk of impaired anal sphincter function. Although clinical incontinence was minimum, an alternative approach to rectocele repair should be considered when anal sphincters are lax.

Anal sphincter injuries from stapling instruments introduced transanally

PURPOSE: Injury sustained from the transanally introduced stapling technique was assessed by comparison with biofragmentable anastomotic ring anastomosis, which excluded anal manipulation. METHODS: A randomized, controlled trial was conducted on consecutive patients undergoing sigmoid colectomy (where pelvic nerve injury was avoided). A bowel function questionnaire was administered six months after surgery. Anorectal manometry and endoanal ultrasonography were performed preoperatively and at six months postoperatively. The observers were blinded to the randomization. RESULTS: There were 18 patients in the transanally introduced stapling technique group and 17 patients in the biofragmentable anastomotic ring group, with no differences in age, gender, Dukes staging, and follow-up. Three of the transanally introduced stapling technique patients had occasional liquid soiling, which was absent in biofragmentable anastomotic ring patients. Mean change in resting anal pressures was also significantly impaired when compared with patients with biofragmentable anastomotic ring (P=0.007). Endosonographic internal sphincter fragmentation was found in five transanally introduced stapling technique patients but none after biofragmentable anastomotic ring anastomosis (P=0.046). Internal sphincter fragmentation was associated with the impaired resting pressures (P=0.007). External sphincter deficiencies were found after transanally introduced stapling technique in two patients (biofragmentable anastomotic ring = 0), and these were associated with the soiling (P=0.005). CONCLUSIONS: The transanally introduced stapling technique may result in anal sphincter defects and impaired anal pressures when assessed at six months of follow-up.

Stratifying risk factors for follow-up: a comparison of recurrent and nonrecurrent colorectal cancer.

INTRODUCTION: The selection of patients for individualized follow-up and adjuvant therapy after curative resection of colorectal carcinoma depends on finding reliable prognostic criteria for recurrence. However, such criteria are not universally accepted, and follow-up is often standardized for all patients without regard for each individuals level of risk of recurrence. Such a system of follow-up is not cost-effective. METHODS: A comparison of operative findings, pathologic features, and follow-up data of 1,731 cases of nonrecurrent colorectal cancer (821 colon, 910 rectum) with 357 cases of recurrent colorectal cancer (164 colon, 193 rectum) following potentially curative surgery was made, and results were analyzed to ascertain criteria for stratifying follow-up according to risk factors. RESULTS: Single-factor analysis showed that Dukes staging and tumor invasion were significantly associated with recurrence in both rectal and colon carcinoma. Tumor fixation and grading were additional significant factors in rectal cancer. Recurrence rates, time to recurrence, site of recurrence (locoregionalvs. distant), and pattern of metastatic spread were not significantly affected by original tumor site. Recurrence was not significantly affected by patient age and gender. Individual surgeon performance in this series had also no significant effects on tumor recurrence. With multivariate analysis only, Dukes staging and tumor invasion into adjacent tissues were found to be independent adverse prognostic factors for recurrence. CONCLUSIONS: Dukes staging and tumor penetration into adjacent tissues are the only significant adverse prognostic factors for tumor recurrence of colonic and rectal carcinoma. Tumor grade and tumor fixation are additional adverse prognostic factors in rectal cancer. Guidelines for follow-up may be based on these factors and follow-up thus stratified according to risk of developing recurrence.

Randomized, controlled trial of low molecular weight heparin vs. no Deep vein thrombosis prophylaxis for major colon and rectal surgery in Asian patients

PURPOSE: Routine deep venous thrombosis prophylaxis is controversial in Asian patients, because deep venous thrombosis incidence was considered negligible. Because of recent reports of significantly higher incidences, a randomized, controlled trial was conducted to assess the effectiveness and complications of enoxaparin prophylaxis (low molecular weight heparins) in major colorectal surgery. METHODS: Three hundred twenty consecutive patients were randomly assigned to control or low molecular weight heparins groups. Patients in the low molecular weight heparins group were given perioperative enoxaparin starting 12 hours before surgery. The surgeon (blinded) assessed for difficulties related to possible enoxaparin administration. Independent blinded observers performed daily clinical assessments and Doppler studies (at the 3rd and 5th postoperative day). Deep venous thrombosis was confirmed by duplex ultrasound, and pulmonary embolism was confirmed by lung scans or postmortem examinations. RESULTS: Deep venous thrombosis developed in 5 of 169 (3 percent) controls and 0 of 134 low molecular weight heparins patients (P=0.045). Three of the deep venous thrombosis patients had pulmonary embolism, which was fatal in one patient. The surgeons were unable to perceive any increased surgical difficulties in the low molecular weight heparins group. The bleeding-related complications were significantly higher in the low molecular weight heparins patients (controls, n=3 (1.8 percent); low molecular weight heparins, n=9 (6.7 percent)). However, apart from one subdural hematoma and two abdominal hemorrhages needing re-exploration, which also occurred in one of the controls, these complications were minor bruises at the wounds, drains, or injection sites. CONCLUSION: Deep venous thrombosis prophylaxis is needed in Asian patients undergoing major colorectal surgery.

Food groups and the risk of colorectal carcinoma in an Asian population

Singapore Chinese have experienced a rapid transition toward a pattern of disease in which lifestyle‐related, chronic, degenerative diseases are major public health concerns. The rates of colorectal carcinoma have increased 2‐fold over the last 3 decades. It has long been known that dietary factors play a role in the risk of this disease, although studies in Asian populations, with their unique dietary intake, have been few.

Anal pressures impaired by stapler insertion during colorectal anastomosis: a randomized, controlled trial.

PURPOSE: The significance of anal sphincter injury from transanal inserted staplers was studied. A randomized, controlled comparison was made of anorectal manometry and clinical function after sigmoid colectomy (avoiding nerve injury from rectal mobilization), anastomosed by either transanal inserted stapler or biofragmentable anastomotic ring (avoiding anal manipulation). METHOD: Fifty-eight consecutive patients with sigmoid adenocarcinoma were randomly assigned to transanal inserted stapler or biofragmentable anastomotic ring groups. Anorectal manometry and clinical bowel function assessment were performed by an independent blinded observer before surgery and six weeks and six months after surgery. RESULTS: At six weeks after surgery, there was significant impairment of mean anal resting pressures (mean impairment, 23 percent;P<0.001) and physiologic anal length (mean impairment, 31 percent;P<0.01) in the transanal inserted stapler group (27 completed the trial), but not in the biofragmentable anastomotic ring group (18 completed the trial). Pressures remained impaired at six months. When changes in the anal pressures were compared between groups, the mean anal resting pressure (P<0.001) and maximum squeeze pressure (P<0.01) at six weeks and mean anal resting pressure at six months (P<0.01) were significantly more impaired in the transanal inserted stapler group. Postoperative bowel function was not different between the two groups. Postoperative complications were similar. In the transanal inserted stapler group one patient died of anastomotic leak sepsis and one had wound infection; in the biofragmentable anastomotic ring group one patient died of myocardial infarct and one had wound infection. CONCLUSION: Direct injuries to the internal anal sphincter occurred after transanal inserted stapler but not biofragmentable anastomotic ring anastomoses. Clinical function was not correspondingly affected, probably because of the adequate residual rectal reservoir after sigmoid colectomy.

Comparison between segmental left and extended right colectomies for obstructing left-sided colonic carcinomas

PURPOSE: This study was designed to compare complications and functions following either radical extended right colectomy without colonic decompression or radical segmental left colectomy with intraoperative decompression for obstructed left-sided colonic carcinomas. METHODS: One hundred three patients with obstructed left-sided colonic carcinoma undergoing primary resection and anastomoses were studied. RESULTS: There were 57 males and 46 females with a median age of 65 (range, 24–98) years and who had a median follow-up of 31 (range, 2–59) months. There were no leaks or intra-abdominal sepsis in the extended right colectomy group (44 patients) compared with one anastomosis leak in the segmental left colectomy (59 patients) group. Median hospital stay was 14 days in both groups, with a range of 8 to 36 days in the segmental left colectomy group and 7 to 44 days in those with extended right resection. One month after surgery, the patients who underwent segmental left colectomy had a median bowel movement of 3 (range, 1–6) per 24 hours compared with those with extended right colectomies who had a median of 5 (2–11) bowel movements per 24 hours. Bowel frequency decreased to four or less episodes per 24 hours in all patients in both groups at six months. CONCLUSION: There was no significant difference between bowel function or complications between the two groups.

Submucosal adrenaline injection for posthemorrhoidectomy hemorrhage

PURPOSE: A technique found effective in stopping active posthemorrhoidectomy bleeding, outside the operating room, is described. METHOD: After resuscitation and sedation, a proctoscope was inserted to identify the bleeding point. 1 to 2 ml of 1/10,000 adrenaline was injected submucosally. RESULTS: This technique was totally successful in 12 of 12 treated patients. CONCLUSION: Submucosal adrenaline injection is a simple and readily accessible technique for managing posthemorrhoidectomy bleeding.

Postoperative intra-abdominal free gas after open colorectal resection

PURPOSE: An erect chest radiograph for subdiaphragmatic free gas can be a useful adjunct in detecting a defect in gastrointestinal continuity. The usefulness of this test after laparotomy has not been defined, because the period of persistence of free gas is unknown. We set out to determine the length of time for natural absorption of postlaparotomy pneumoperitoneum in a prospective cohort study. METHOD: Plain erect chest radiographs were performed on the second and fourth postoperative day and daily thereafter until the disappearance of subdiaphragmatic free gas after laparotomy. RESULTS: Seventy-five consecutive patients were studied after informed consent. The mean age was 62.1 (standard error of the mean, 1.7) years. On the fifth postoperative day, sixth postoperative day, and seventh postoperative day, 71.6, 80, and 89 percent of patients, respectively, had no visible subdiaphragmatic gas. Five patients had gas persisting beyond the tenth postoperative day. Two of these patients did not have an anastomosis. The use of drainage tubes did not affect significantly the mean time to disappearance of subdiaphragmatic free gas (4.5vs. 4.9 days;P=0.45;t-test). The duration of surgery, body mass index, and time to resume bowel function had no significant effect on gas disappearance. Two patients had a clinical leak on the fifth postoperative day. This was manifested as an increase in the collection of subdiaphragmatic gas during the course of a day. CONCLUSION: By the sixth postoperative day 80 percent of patients had no subdiaphragmatic free gas on an erect chest radiograph regardless of the presence of a drainage tube. The erect chest radiograph may therefore be a simple and readily available adjunct in the evaluation of postoperative abdominal pain, especially after the sixth postoperative day when a similar prior examination is done routinely on the fourth postoperative day for comparison.

Management of Acute Bleeding Per Rectum

BACKGROUND Bleeding per rectum is a common indication for acute hospital admissions to the colorectal department. The frequencies of aetiologies in Singapore are different from those in Western populations. A retrospective analysis of the demography, pathology and management of acute bleeding per rectum was performed to determine the outcome and difference in aetiology from the West. METHODS During the 1-year period from 1 October 1995 to 30 September 1996, 547 patients were admitted to Singapore General Hospital form the emergency department for acute bleeding per rectum. There were 377 males and 170 females; the mean age was 42 years (range, 15-97 years). RESULTS Of the patients admitted, 87% wer admitted due to perianal conditions diagnosed at bedside proctoscopy, where haemorrhoids mad up 94%. One percent bled from the upper gastrointestinal tract, while 12% bled from colorectal pathology. Massive bleeding form the colorectum was uncommon. Less than one third of the 47 patients required blood transfusions. Colonoscopy was the most useful diagnostic tool for bleeding from the colorectum. The more common colonic pathologies were diverticular disease (33%), adenomas (18%), and malignancy (26%), accounting for the majority of acute patient admissions. Colonic causes of bleeding were less common and were most stable. There were differences in the frequencies of aetiologies in our population compared ot Western populations. Understanding the common pathologies and outcomes guides the management fo our patients.