Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Tuberculous meningitis in an immunocompetent male complicated by hydrocephalus

A 39-year-old man, born in India but resident in the UK for 10 years, was travelling in America when he became feverish with an altered mentation. He reported a 10-day history of fever, photophobia, headache and fatigue. His medical history included hypothyroidism and migraine. He was a non-smoker, did not consume alcohol and denied a history of drug use. He was transferred to the emergency department. Laboratory investigations confirmed hyponatraemia (sodium 128 mmol/L). A chest radiograph confirmed no focal consolidation. Further investigation with a CT brain was unremarkable. A lumbar puncture was suggestive of viral meningitis, with a raised white cell count, lymphocytosis, high protein and low glucose. His PCR was negative for enterovirus and herpes simplex virus. Further investigation with a CT thorax, abdomen and pelvis demonstrated bilateral upper-lobe infiltrations. A bronchoalveolar lavage was negative for acid alcohol fast bacilli (AAFB). A diagnosis of tuberculous meningitis was rendered following a repeat lumbar puncture. Gram stain revealed AAFB and PCR was also positive. He started antitubercular treatment and corticosteroids. A repeat CT brain demonstrated ventriculomegaly, suggestive of hydrocephalus and an MRI head revealed likely communicating hydrocephalus with basilar enhancement. He was repatriated to the UK. Eleven days post transfer, he became acutely confused and required external ventricular drain insertion. After surgical management of his hydrocephalus, there was no further neurological deterioration. He remains committed to his neurorehabilitation.

Scurvy in an alcoholic patient treated with intravenous vitamins

Vitamin C deficiency is rare in developed countries but there is an increased prevalence in chronic alcohol abusers. In the UK, it is common practice to treat patients with chronic alcoholism who are admitted to hospital with intravenous vitamins B1, B2, B3, B6 and C for 2-3 days, followed by oral thiamine and vitamin B-compound tablets. This is a case of a 57-year-old man with a history of chronic alcoholism and chronic obstructive lung disease who was admitted to the intensive care unit for pneumonia requiring ventilatory support. He was given high doses of intravenous vitamins B1, B2, B3, B6 and C for 3 days then oral thiamine and vitamin B compound tablets but developed scurvy 4 days later. He was restarted on oral vitamin C supplementation and showed signs of improvement within 3 days of treatment.

Unsuspected pulmonary alveolar proteinosis in a patient with a slow resolving pneumonia: A case report

Pulmonary Alveolar Proteinosis (PAP) is a rare condition with an incidence of one in two million and is classified as primary or secondary. This is the first reported case presenting as a slow resolving pneumonia.

Purification and partial characterization of glycogen synthase kinase-3 from rabbit liver

Glycogen synthase kinase-3 (GSK-3) was purified from rabbit liver to homogeneity by ultracentrifugation, ion-exchange chromatography on DEAE-cellulose, Cellulose phosphate, CM-Sephadex and Fast Protein Liquid Chromatography (FPLC) on Mono-S column. The enzyme was purified approximately 20,000 fold with an approximate 2% recovery. The purified enzyme showed a single band on SDS-polyacrylamide gel electrophoresis. GSK-3 is a monomeric enzyme with a molecular weight of 50,000-52,000 as derived from SDS-polyacrylamide gel electrophoresis and gel filtration. The purified enzyme was indeed a GSK-3 since it phosphorylated three sites, i.e., 3a, 3b, and 3c on liver glycogen synthase. GSK-3 incorporated up to 2.6 mol Pi/mol glycogen synthase subunit with a concomitant inactivation of glycogen synthase activity.