Effect of aspirin in vascular surgery in patients from a randomized clinical trial (POISE-2).

BACKGROUND: In the POISE-2 (PeriOperative ISchemic Evaluation 2) trial, perioperative aspirin did not reduce cardiovascular events, but increased major bleeding. There remains uncertainty regarding the effect of perioperative aspirin in patients undergoing vascular surgery. The aim of this substudy was to determine whether there is a subgroup effect of initiating or continuing aspirin in patients undergoing vascular surgery. METHODS: POISE-2 was a blinded, randomized trial of patients having non-cardiac surgery. Patients were assigned to perioperative aspirin or placebo. The primary outcome was a composite of death or myocardial infarction at 30 days. Secondary outcomes included: vascular occlusive complications (a composite of amputation and peripheral arterial thrombosis) and major or life-threatening bleeding. RESULTS: Of 10 010 patients in POISE-2, 603 underwent vascular surgery, 319 in the continuation and 284 in the initiation stratum. Some 272 patients had vascular surgery for occlusive disease and 265 had aneurysm surgery. The primary outcome occurred in 13·7 per cent of patients having aneurysm repair allocated to aspirin and 9·0 per cent who had placebo (hazard ratio (HR) 1·48, 95 per cent c.i. 0·71 to 3·09). Among patients who had surgery for occlusive vascular disease, 15·8 per cent allocated to aspirin and 13·6 per cent on placebo had the primary outcome (HR 1·16, 0·62 to 2·17). There was no interaction with the primary outcome for type of surgery (P = 0·294) or aspirin stratum (P = 0·623). There was no interaction for vascular occlusive complications (P = 0·413) or bleeding (P = 0·900) for vascular compared with non-vascular surgery. CONCLUSION: This study suggests that the overall POISE-2 results apply to vascular surgery. Perioperative withdrawal of chronic aspirin therapy did not increase cardiovascular or vascular occlusive complications. Registration number: NCT01082874 ( http://www.clinicaltrials.gov).

Covert stroke after non-cardiac surgery: a prospective cohort study.

BACKGROUND: Overt stroke after non-cardiac surgery has a substantial impact on the duration and quality of life. Covert stroke in the non-surgical setting is much more common than overt stroke and is associated with an increased risk of cognitive decline and dementia. Little is known about covert stroke after non-cardiac, non-carotid artery surgery. METHODS: We undertook a prospective, international cohort study to determine the incidence of covert stroke after non-cardiac, non-carotid artery surgery. Eligible patients were ≥65 yr of age and were admitted to hospital for at least three nights after non-cardiac, non-carotid artery surgery. Patients underwent a brain magnetic resonance study between postoperative days 3 and 10. The main outcome was the incidence of perioperative covert stroke. RESULTS: We enrolled a total of 100 patients from six centres in four countries. The incidence of perioperative covert stroke was 10.0% (10/100 patients, 95% confidence interval 5.5-17.4%). Five of the six centres that enrolled patients reported an incident covert stroke, and covert stroke was found in patients undergoing major general (3/27), major orthopaedic (3/41), major urological or gynaecological (3/22), and low-risk surgery (1/12). CONCLUSIONS: This international multicentre study suggests that 1 in 10 patients ≥65 yr of age experiences a perioperative covert stroke. A larger study is required to determine the impact of perioperative covert stroke on patient-important outcomes. CLINICAL TRIAL REGISTRATION: NCT01369537.

Role of aspirin for prevention and treatment of perioperative cardiovascular events.

Among adults undergoing non-cardiac surgery who are at risk of a myocardial infarction, a long-standing question has been whether these patients should receive aspirin throughout the perioperative period. A large (n = 10,010 patients) international trial (POISE-2) demonstrated that perioperative aspirin did not prevent myocardial infarction, and the result was consistent both for patients who had been taking aspirin before the trial (continuation stratum, 4382 patients) and for patients who had not been taking aspirin before the trial (initiation stratum, 5628 patients). Aspirin did, however, increase the risk of major bleeding. Therefore, the best evidence does not support the use of aspirin for the prevention of myocardial infarction in patients undergoing non-cardiac surgery. In patients who have an indication for long-term aspirin usage and have their aspirin held during the perioperative period, it is important to ensure aspirin is restarted after the high-risk period for bleeding has passed (i.e., 8-10 days after surgery).

Meta-analysis: vasoactive medications for the management of acute variceal bleeds.

BACKGROUND: Vasoactive medications such as vasopressin, somatostatin and their analogues (terlipressin, vapreotide and octreotide) are commonly used for the treatment of acute variceal bleeding. However, the risks and benefits of these interventions are not well understood. AIM: To undertake a meta-analysis of the efficacy of vasoactive medications in patients having acute variceal bleeds. METHODS: Randomised controlled trials (RCTs) of vasopressin, somatostatin and their analogues, administered to patients with acute variceal bleeds were identified based on systematic searches of nine electronic databases and multiple sources of grey literature. RESULTS: The search identified 3011 citations, and 30 trials with a total of 3111 patients met eligibility criteria. The use of vasoactive agents was associated with a significantly lower risk of 7-day mortality (RR 0.74; 95% CI 0.57-0.95; P = 0.02; I(2) = 0%; moderate quality of evidence), and a significant improvement in haemostasis (RR 1.21, 95% CI 1.13-1.30; P < 0.001; I(2) = 28%; very low quality of evidence), lower transfusion requirements (pooled mean difference -0.70 units of blood transfused, 95% CI -1.01 to -0.38; P < 0.001; I(2) = 82%; moderate quality of evidence), and a shorter duration of hospitalisation (pooled mean difference -0.71 days; 95% CI -1.23 to -0.19; P = 0.007; I(2) = 0%; low quality of evidence). Studies comparing different vasoactive agents did not show a difference in efficacy, although the quality of evidence was very low. CONCLUSIONS: The use of vasoactive agents was associated with a significantly lower risk of acute all-cause mortality and transfusion requirements, and improved control of bleeding and shorter hospital stay. Studies comparing different vasoactive medications failed to demonstrate a difference in efficacy.