Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Is there evidence of an association between postnatal distress and premenstrual symptoms?

Background There is a widely held assumption in the literature that a well-established link exists between postnatal depressive and premenstrual symptoms. However, on examination of existing research, certain methodological limitations were identified including inadequate methods of assessment and a heavy reliance upon the retrospective assessment of either postnatal or premenstrual symptoms, giving rise to concern regarding the validity of any conclusions. Methods A community sample of 63 women completed a daily menstrual symptom diary for two consecutive months. Women's Edinburgh Postnatal Depression Scale score, recorded 1–3 years previously, was provided by their Health Visitor. Results Only one participant showed evidence of both postnatal and premenstrual distress when using an EPDS cut-off of > 12 and defined criteria for premenstrual symptom assessment. When scores were treated as a continuum, there was no association between postnatal distress and psychological premenstrual symptoms and only a trend towards significance between postnatal distress and physical premenstrual symptoms. Limitations Due to the recruitment method, there is some uncertainty regarding the overall response rate. Although this was not a large sample, it compares favourably with many other studies where daily data are collected. The particular focus was examining whether postnatal depressive symptoms predict premenstrual distress (not vice versa). Conclusions This study found little evidence to support the widely held assumption of a clear relationship between postnatal distress and premenstrual symptoms