Use of visible spectrophotometry to assess tissue oxygenation in the colostomy stoma.

The aims of this study were to determine the normal range of tissue oxygenation (SO(2)) in the "mature" colostomy stomacolostomy stoma and to investigate whether there were any diurnal variationsdiurnal variations in the SO(2) values. Ten patients with an end colostomy for a minimum duration of three months and using conventional colostomy bags were included in this study. Tissue SO(2) Tissue SO(2) was measured on the stoma using visible wavelength spectroscopy (Whitland RM 200, Whitland Research, Whitland, UK) The measurements were carried out on each patient on three occasions: the first early in the morning (designated "baseline"), a second after 6 h and the third on the next day at 24 h. The results showed that the mean baseline SO(2) in the colostomy stoma was 77.6 +/- 6.8 and there were no differences in the SO(2) measurements between the baseline, 6 h and the 24 h values. There were also no differences in the SO(2) values between the four quadrants of the stomas. In conclusion, visible wavelength spectrophotometry can reliably measure stomal SO(2) in a non-invasive way. No significant diurnal variations in the stomal SO(2) values were detected.

Intraoperative measurement of colonic oxygenation during bowel resection.

Recently lightguide spectrophotometry (LGS) has been investigated for assessing bowel mucosal oxygenation and may prove helpful in the diagnosis of bowel ischaemia. This pilot study explores the use of LGS and laser Doppler flowmetry (LDF) to measure SO2 and perfusion in the bowel during key stages of colon surgery. SO2 and perfusion in the mucosal and serosal layers of the rectum, sigmoid and descending colon were measured in 7 patients by LGS (Whitland Research, UK) and LDF (Moor Instruments, UK) respectively at four stages (baseline, after mobilisation of the sigmoid, after ligation of the inferior mesenteric artery (IMA) and after complete devascularisation of the sigmoid). The sigmoid mucosal SO2 and LDF values were significantly lower than the baseline after the ligation of IMA and devascularisation. Mean (SD) baseline sigmoid mucosal SO2 (73%) decreased to 55% after ligation of IMA and to 39% after complete devascularisation. The sigmoid serosal SO2 did not show any change after ligation of IMA and showed only 7% decrease after devascularisation. There was no difference in baseline SO2 and LDF values in different parts of the bowel but the mean mucosal baseline SO2 (75%) was significantly lower than that in the serosa (87%). In conclusion, mucosal SO2 measurements can accurately diagnose bowel ischaemia but serosal SO2 does not reflect mucosal ischaemia.

Transanal Irrigation for Refractory Chronic Idiopathic Constipation: Patients Perceive a Safe and Effective Therapy.

Background. Transanal irrigation (TAI) can successfully treat neurogenic bowel dysfunction (NBD), but patient perception of its use in chronic idiopathic constipation (CIC) is unknown. Objective. To evaluate patient perceptions of the efficacy and safety of TAI for CIC and whether there are predictive factors of perceived treatment response. Methods. Prospective data collection of baseline physiology and symptom severity; retrospective evaluation of efficacy and safety perceptions using a snapshot survey. All patients fulfilling the Rome III criteria for functional constipation with chronic idiopathic aetiology were included. The main outcome measure was the duration of patients' usage of TAI. Results. 102 patients reported 21,476 irrigations over 119 patient years, with a mean duration of therapy use of 60.5 weeks [SD 73.2 : SE 7.3]. Overall symptom improvement included general well-being (65%), rectal clearance (63%), bloating (49%), abdominal pain (48%), and bowel frequency (42%). 68 patients (67%) were "moderately better" or "very much better" on a satisfaction question. Reported complications were minor. No correlation was demonstrated between duration of therapy use and baseline measures. Conclusion. A significant proportion of CIC sufferers use TAI as a long-term or bridging therapy and perceive it as safe. This therapy demands a prospective investigation of efficacy and safety.

Functional defecation disorder as a clinical subgroup of chronic constipation: analysis of symptoms and physiological parameters.

OBJECTIVE: Patients with functional constipation can be classified according to symptoms and physiological parameters as either having a disorder of defecation or having normal defecation. It is hypothesized that the disordered defecation, where it exists, is a causative factor of the constipation. However, the utility of this classification has yet to be proven in terms of predicting response to therapy. The definitions are non-specific and based on tests that are done in an artificial setting and with derived normal ranges. It is therefore possible that the symptoms and physiological parameters of a defecatory disorder may occur as a continuous spectrum in these patients, rather than defining a discrete entity or subtype. The aim of this study was to use cluster analysis and factor analysis of defecatory symptoms and physiological parameters to look for evidence of subgroups in patients with functional constipation. MATERIAL AND METHODS: Consecutive patients presenting to a specialist constipation clinic and satisfying the inclusion criteria were assessed to determine the severity of defecatory symptoms, and underwent isotope defecating proctography and the Sitzmark transit study. Assessments were made contemporaneously and results of any test not performed within 6 weeks of the initial assessment were excluded. Principle components analysis and cluster analysis were performed to look for evidence of subgroups. Relationships between evacuatory symptoms, index parameters, and test results were explored. The detailed and unselected nature of the analyses produced hundreds of test results, and statistically significant results were critically evaluated in this context. RESULTS: A total of 116 patients were studied (age range 18-73 years, mean 40.5 years). Based on the results of the transit study and proctography, 38% of patients showed evidence of slow transit constipation, 20% FDD (functional defecation disorder), 29% both, and 12% neither. Principle components analysis did not demonstrate an obvious dimension reduction for the variables tested. Cluster analysis (over 150 solutions tested) failed to show evidence of clustering. There were no useful predictive relationships between evacuatory symptoms, index parameters and test results. CONCLUSIONS: We used multiple statistical analyses to look for clustering and predictive relationships between clinical and physiological parameters in consecutive patients with functional constipation and found no evidence of the existence of a subgroup of patients with a defecatory disorder. This may be due to weaknesses in the study design, poor validity of the assessments performed, or that defecatory features do not identify a distinct pathophysiological entity, but rather are manifested variably as a continuous spectrum.