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

A high-resolution melt curve toolkit to identify lineage-defining SARS-CoV-2 mutations

The emergence of severe acute respiratory syndrome 2 (SARS-CoV-2) variants of concern (VOCs), with mutations linked to increased transmissibility, vaccine escape and virulence, has necessitated the widespread genomic surveillance of SARS-CoV-2. This has placed a strain on global sequencing capacity, especially in areas lacking the resources for large scale sequencing activities. Here we have developed three separate multiplex high-resolution melting assays to enable the identification of Alpha, Beta, Delta and Omicron VOCs. The assays were evaluated against whole genome sequencing on upper-respiratory swab samples collected during the Alpha, Delta and Omicron [BA.1] waves of the UK pandemic. The sensitivities of the eight individual primer sets were all 100%, and specificity ranged from 94.6 to 100%. The multiplex HRM assays have potential as a tool for high throughput surveillance of SARS-CoV-2 VOCs, particularly in areas with limited genomics facilities

An ecological survey of Natal: the Pietermaritzburg district

A general account of the Vegetation of Natal(Annals of the Natal Museum II 1912) forms a prelimin­ary paper to the present one, in which the more detail­ed ecological survey of this colony is begun, In the first part of the former paper the various factors that influence plant life in Natal - geological structure and soil conditions, rainfall and mists, temperature, light, winds, fires, and animals - were described and discussed. Even in the comparatively small area dealt with in the present paper, most of the types of plant formation determined by those factors are found. In a general paper, which deals with the vegetation of a whole county most attention is naturally paid to the climatic factors, but when a detailed analysis of the various plant associations in a limited area is the object in view, the edaphic factors are of most importance, consequently in this paper more attention has been paid to the latter. At the same time it is well to keep in mind how greatly the edaphic factors are themselves influenced by the climatic factors and nowhere can this he better seen than in Natal

Plant Succession and Plant Distribution in South Africa.

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THE GROWTH-FORMS OF NATAL PLANTS

Volume: 5Start Page: 605End Page: 63

An introduction to the flora of Natal and Zululand /

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The grasses and grasslands of South Africa,

Mode of access: Internet