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

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

Avaliação intra-operatória da pressão portal e resultados imediatos do tratamento cirúrgico da hipertensão portal em pacientes esquistossomóticos submetidos a desconexão ázigo-portal e esplenectomia Intra-operative evaluation of portal pressure and immediate results of surgical treatment of portal hypertension in schistosomotic patients submitted to esophagogastric devascularization with splenectomy

RACIONAL: No Brasil a principal causa de hipertensão portal é a esquistossomose mansônica na sua forma hepatoesplênica. Com relação ao seu tratamento, a preferência da maioria dos autores no Brasil recai sobre a desconexão ázigo-portal e esplenectomia geralmente associada à escleroterapia endoscópica pós-operatória para tratamento dessa enfermidade. No entanto, não estão bem estabelecidas as alterações hemodinâmicas portais decorrentes do tratamento cirúrgico da hipertensão portal e sua influência no resultado desse tratamento. OBJETIVOS: Avaliar o impacto imediato da desconexão ázigo-portal e esplenectomia na pressão portal e também os resultados do tratamento cirúrgico da hipertensão portal no que se refere à recidiva hemorrágica e ao calibre das varizes de esôfago. CASUÍSTICA E MÉTODO: Foram estudados 19 pacientes com esquistossomose hepatoesplênica e hipertensão portal, com história de hemorragia digestiva alta por ruptura de varizes esofágicas, com idade média de 37,9 anos. Estes pacientes não haviam sido submetidos a tratamento prévio e foram, eletivamente, tratados cirurgicamente com desconexão ázigo-portal e esplenectomia. Durante a cirurgia, foi avaliada a pressão portal, no início e no final do procedimento, através da cateterização da veia porta por cateter de polietileno introduzido por veia jejunal. Todos os pacientes foram submetidos a endoscopia no pré e no pós-operatório (em torno do 60&ordm; dia do pós-operatório) para avaliar, segundo classificação de Palmer, a variação do calibre das varizes esofagianas após a desconexão ázigo-portal e esplenectomia. RESULTADOS: Todos os pacientes apresentaram queda da pressão portal, sendo a média desta queda, após a desconexão ázigo-portal e esplenectomia, de 31,3%. Na avaliação pós-operatória (endoscopia após cerca de 60 dias) houve redução significativa do calibre das varizes esofagianas quando comparadas ao pré-operatório. CONCLUSÃO: A desconexão ázigo-portal e esplenectomia promoveram queda imediata na pressão portal, com conseqüente diminuição do calibre das varizes esofágicas. Observou-se ainda que não é insignificante o risco de mortalidade e complicações graves relacionados a essa técnica.<br>BACKGROUND: The main cause of portal hypertension in Brazil is the hepato-splenic form of mansonic schistosomiasis and the most employed technique for the surgical approach of this disease is the esophagogastric devascularization with splenectomy, generally associated to postoperative endoscopical esophageal varices sclerotherapy. The hemodynamic alterations after surgical treatment and its possible influence on the outcome are not well established. AIM: To evaluate the immediate impact of esophagogastric devascularization with splenectomy upon portal pressure as well as the results of the surgical treatment on digestive hemorrhage recurrence and on esophageal varices. METHODS: Nineteen patients with mean age of 37.9 years and portal hypertension and previous episodes of digestive hemorrhage caused by esophageal varices rupture due to hepato-splenic schistosomiasis were studied. None of the patients had received any treatment prior to the surgery and underwent to elective esophagogastric devascularization with splenectomy. Portal pressure was assessed at the beginning and at the end of esophagogastric devascularization with splenectomy through portal vein catheterization with a polyethylene catheter introduced through a jejunal branch vein. All patients were submitted to digestive endoscopy before and after the surgery, in order to classify the size of esophageal varices after esophagogastric devascularization with splenectomy according to Palmer’s classification. RESULTS: In all patients the portal pressure had diminished with a mean decrease of 31.3% after esophagogastric devascularization with splenectomy. In the postoperative endoscopic follow-up (1 month), the esophageal varices showed a statistically significant reduction in their size, when compared to the pre-surgical measurements. CONCLUSION: These results have demonstrated that the esophagogastric devascularization with splenectomy promotes immediate decrease in the portal pressure and a consequent reduction in the esophageal varices size. We also observed that the risk of mortality and severe complications related to this technique is not insignificant

Applying physicochemical approaches to control phosphogypsum heavy metal releases in aquatic environment

One of the most important sources of solid waste in the Mediterranean Basin ecosystem originated from the phosphate fertilizer industries, which discharge phosphogypsum (PG) directly into aquatic environments or are stacked on stockpiles. The present study investigates metal release from PG under the influence of variable pH, increasing PG mass content, and complexing organic matter ligands. Major ions from PG leachates, grain size and charge, main functional groups along with metal leachability (Pb, Cd, Cr, Cu, and Zn) were determined using ion chromatography, laser diffraction, zetameter, Fourier transform infrared spectroscopy, and atomic absorption spectroscopy, respectively. The complete dissolution of PG recorded is at 2 g/L. Saturation and supersaturation with respect to PG may occur at concentrations of 3 and 4 g/L, respectively, revealing a clustering phenomenon leading to heavy metal encapsulation within the aggregates. Organic ligands such as citrate may trigger the cationic exchange within the PG suspension leading to ion release. As these factors are considered as specific process involving the release of contaminants from PG during storage under natural conditions, this study could set the foundations for PG remediation in aquatic environment. Organic ligands under controlled pH conditions could be utilized in treating fertilizer industrial wastes by taking into consideration the particularity of the receiving area, thus decreasing metal hazardous impact on natural media. © 2013 Springer-Verlag Berlin Heidelberg.SCOPUS: ar.jSCOPUS: ar.jinfo:eu-repo/semantics/publishe