On effectiveness in colorectal surgery : mechanical bowel preparation or not in elective colonic surgery and treatment options for elderly patients with rectal cancer
Abstract: The management of patients undergoing colorectal surgery has changed in recent decades. Efforts have been made to show that perioperative physiological stress to the patient can be minimised with standardised care programmes and thus improve short term outcome after colorectal surgery. Mechanical bowel preparation (MBP), for instance, has been questioned as part of standard management. There are studies highlighting the effect of cancer treatment and its side effects in the elderly, showing that geriatric patients benefit from oncological therapy in much the same way as younger patients. The impact of this information on surgical and oncological practice in Sweden today is not known. To assess the effectiveness of colorectal surgery we need both randomised controlled trials and population-based cohort studies. We have performed a trial on colonic surgery with and without preoperative mechanical bowel preparation, as well as a nation-wide register study comparing treatment and outcome of rectal cancer in two age groups. In a randomised controlled trial 1505 patients from 21 hospitals were randomised to MBP or no-MBP prior to open elective colonic resection. There were no differences in overall complication rates between the groups: cardiovascular 5.1% with MBP vs. 4.6% without MBP; general infection 7.9% vs. 6.8%; and surgical site complications 15.1% vs. 16.1%. The proportion of patients reaching at least one primary endpoint was 24.5% vs. 23.7% respectively. The patients experience of and postoperative recovery after MBP or no-MBP was evaluated in 105 of the patients in the bowel preparation trial at three of the participating hospitals. Sixty-five patients received MBP and 40 patients did not. In the MBP group 52% needed assistance with bowel preparation. Day 4 postoperatively patients in the no-MBP group perceived more discomfort than patients in the MBP group, p<0.05. Bowel emptying occurred significantly earlier in the no-MBP group than in the MBP group, p<0.05.In an experimental study the effect of MBP on intramucosal bacterial count was evaluated. Macroscopically normal colon mucosa was collected from 37 patients (20 MBP and 17 No-MBP) undergoing elective colorectal surgery at three hospitals. MBP did not influence the median colony count of E. coli, Bacteroides, or total median colony count, information that was previously unknown. These three studies imply that MBP can be omitted before elective colonic resection. In a population-based register study, treatment for rectal cancer in patients ≥ 75 years and those < 75 years was evaluated using data from the Swedish Rectal Cancer Register 1995-2004 (N=15104). This study revealed that preoperative radiotherapy was used less in patients > 75 years. There was also a higher threshold for surgery in this group, and they more often received a permanent stoma compared to younger patients. Outcome in terms of 5-year local recurrence rate and 5-year cancer-specific survival differed very little between the older and younger patient groups who underwent abdominal tumour resection with curative intent. We suggest future studies focusing on ways of reducing surgical and perioperative stress and on quality of life when assessing suitable treatment modalities for rectal cancer.
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