Tranexamic acid is associated with less blood transfusion in off-pump coronary artery bypass graft surgery: a systematic review and meta-analysis.

OBJECTIVE: Tranexamic acid reduces blood loss and transfusion in on-pump coronary artery bypass graft (CABG) surgery. Compared with on-pump, off-pump surgery is associated with less blood loss and transfusion. Therefore, tranexamic acid may be less effective for off-pump surgery, and its safety profile may be different in this setting. The aim of this study was to determine the efficacy and safety of tranexamic acid for off-pump CABG surgery. DESIGN: Systematic review and meta-analysis. SETTING: University of Edinburgh. INTERVENTIONS: The administration of tranexamic acid. METHODS: A systematic review of randomized controlled trials administering tranexamic acid to patients undergoing off-pump CABG surgery. A meta-analysis of 24-hour blood loss, postoperative allogeneic transfusion, and thromboembolic events. MEASUREMENTS AND MAIN RESULTS: Eight trials were identified. The lack of appropriate data limited the meta-analysis on blood loss. Tranexamic acid significantly reduced the overall risk of allogeneic blood component transfusion (risk ratio = 0.47; 95% confidence intervals, 0.33-0.66; p < 0.0001) and packed red blood cell transfusions (risk ratio = 0.51; 95% CI, 0.36-0.71; p = 0.0001). No association was found between tranexamic acid and myocardial infarction, stroke, or pulmonary embolism. Population sizes of meta-analyses ranged from 466 to 544. CONCLUSIONS: Tranexamic acid reduces blood transfusion after off-pump surgery. Although no association with adverse events was found, the population sample size was too small to detect rare but clinically significant adverse events. A well-designed randomized controlled trial with an appropriate sample size is required to confirm tranexamic acid effectiveness and safety in off-pump CABG surgery.

Meningococcal meningitis and COVID-19 co-infection.

Bacterial co-infection in the ongoing pandemic of COVID-19 is associated with poor outcomes but remains little understood. A 22-year-old woman presented with a 3-week history of fever, headache, neck stiffness, rigours and confusion. She was noted to have a purpuric rash over her hands and feet. Cerebrospinal fluid bacterial PCR was positive for Neisseria meningitidis A concurrent nasopharyngeal RT-PCR was positive for SARS-CoV-2, the causative virus of COVID-19. She was treated with antibiotics for bacterial meningitis and made a complete recovery. Bacterial infection from nasopharyngeal organisms has followed previous pandemic viral upper respiratory illnesses and the risk of bacterial co-infection in COVID-19 remains unclear. Research characterising COVID-19 should specify the frequency, species and outcome of bacterial co-infection. Management of bacterial co-infection in COVID-19 presents major challenges for antimicrobial stewardship and clinical management. Judicious use of local antibiotic guidelines and early liaison with infection specialists is key.

Liquorice-induced apparent mineralocorticoid excess presenting in the emergency department.

A 65-year-old woman with a background of myalgic encephalitis, who was taking alternative medicines and dietary supplements, presented with hypokalaemia and hypertension. After a thorough history it became apparent that this was most likely secondary to regular consumption of liquorice tea. The patient was advised to discontinue drinking this tea and was discharged. Follow-up showed normalising blood pressure and hypokalaemia, with a normal aldosterone:renin ratio.

An experimental model to measure the ability of headphones with active noise control to reduce patient's exposure to noise in an intensive care unit.

BACKGROUND: Defining the association between excessive noise in intensive care units, sleep disturbance and morbidity, including delirium, is confounded by the difficulty of implementing successful strategies to reduce patient's exposure to noise. Active noise control devices may prove to be useful adjuncts but there is currently little to quantify their ability to reduce noise in this complex environment. METHODS: Sound meters were embedded in the auditory meatus of three polystyrene model heads with no headphones (control), with headphones alone and with headphones using active noise control and placed in patient bays in a cardiac ICU. Ten days of recording sound levels at a frequency of 1 Hz were performed, and the noise levels in each group were compared using repeated measures MANOVA and subsequent pairwise testing. RESULTS: Multivariate testing demonstrated that there is a significant difference in the mean noise exposure levels between the three groups (p < 0.001). Subsequent pairwise testing between the three groups shows that the reduction in noise is greatest with headphones and active noise control. The mean reduction in noise exposure between the control and this group over 24 h is 6.8 (0.66) dB. The use of active noise control was also associated with a reduction in the exposure to high-intensity sound events over the course of the day. CONCLUSIONS: The use of active noise cancellation, as delivered by noise-cancelling headphones, is associated with a significant reduction in noise exposure in our model of noise exposure in a cardiac ICU. This is the first study to look at the potential effectiveness of active noise control in adult patients in an intensive care environment and shows that active noise control is a candidate technology to reduce noise exposure levels the patients experience during stays on intensive care.