A retrospective analysis of 20,178 adult neurological infection admissions to United Kingdom critical care units from 2001 to 2020.

BACKGROUND: Neurological infection is an important cause of critical illness, yet little is known on the epidemiology of neurological infections requiring critical care. METHODS: We analysed data on all adults with proven or probable neurological infection admitted to UK (NHS) critical care units between 2001 and 2020 reported to the Intensive Care National Audit and Research Centre. Diagnoses, physiological variables, organ support and clinical outcomes were analysed over the whole period, and for consecutive 5-year intervals within it. Predictors of in-hospital mortality were identified using a backward stepwise regression model. RESULTS: We identified 20,178 critical care admissions for neurological infection. Encephalitis was the most frequent presentation to critical care, comprising 6725 (33.3%) of 20,178 cases. Meningitis- bacterial, viral or unspecified cases - accounted for 10,056 (49.8%) of cases. In-hospital mortality was high, at 3945/19,765 (20.0%) overall. Over the four consecutive 5-year periods, there were trends towards higher Glasgow Coma Scale scores on admission, longer critical care admissions (from median 4 [IQR 2-8] to 5 days [IQR 2-10]), and reduced in-hospital mortality (from 24.9 to 18.1%). We identified 12 independent predictors of in-hospital death which when used together showed good discrimination between patients who die and those who survive (AUC = 0.79). CONCLUSIONS: Admissions with neurological infection to UK critical care services are increasing and the mortality, although improving, remains high. To further improve outcomes from severe neurological infection, novel approaches to the evaluation of risk stratification, monitoring and management strategies are required.

KEY POINTS: • Meningitis comprised 50% and encephalitis comprised 33% of neurological infections requiring critical care admission. • During the 20-year study period, there was a progressive trend of increasing neurological infection admissions to critical care, and a reduction in the overall mortality rate.

A case series of vaccine-induced thrombotic thrombocytopenia in a London teaching hospital.

The ChAdOx1 nCoV-19 vaccine has been associated with increased risk of thrombosis. Understanding of the management of these rare events is evolving, and currently recommended treatments include human normal immunoglobulin and nonheparin anticoagulation such as direct oral anticoagulants. Our report describes three consecutive patients presenting to a London teaching hospital with vaccine-induced thrombotic thrombocytopenia (VITT), also referred to as vaccine-induced prothrombotic immune thrombocytopenia. The patients ranged in age from 40 to 54 years and two had no known previous medical comorbidities. Two patients had cerebral venous sinus thrombosis and one had a deep vein thrombosis. Two were treated with anticoagulation, one with oral rivaroxaban and the other with an intravenous argotraban infusion that was later converted to oral apixaban. One patient received three doses of human normal immunoglobulin and 5 days of therapeutic plasma exchange. This case series may be used to improve understanding of the clinical course and management of VITT.

The 'top 100' drugs and classes in England: an updated 'starter formulary' for trainee prescribers.

AIMS: Prescribing is a complex skill required of doctors and, increasingly, other healthcare professionals. Use of a personal formulary can help to develop this skill. In 2006-9, we developed a core list of the 100 most commonly prescribed drugs. Our aim in the present study was to update this 'starter formulary' to ensure its continued relevance for prescriber training. METHODS: We analysed large contemporary primary and secondary care datasets to identify the most frequently prescribed medicinal products. Items were classified into natural groups, broadly following their British National Formulary classification. The resulting drug groups were included in the core list if they comprised ≥0.1% prescriptions in both settings or ≥0.2-0.3% prescriptions in one setting. Drugs from emergency guidelines that did not qualify by prescribing frequency completed the list. RESULTS: Over 1 billion primary care items and approximately 1.8 million secondary care prescriptions were analysed. The updated list comprises 81 drug groups commonly prescribed in both settings; six from primary care; seven from secondary care; and six from emergency guidelines. Eighty-eight per cent of the formulary was unchanged. Notable changes include entry of newer anti-epileptics and dipeptidyl peptidase-4 inhibitors and exit of phenytoin and thiazolidinediones. CONCLUSIONS: The relative stability of the core drug list over 9 years and the current update ensure that learning based on this list remains relevant to practice. Trainee prescribers may be encouraged to use this 'starter formulary' to develop a sound basis of prescribing knowledge and skills that they can subsequently apply more widely.

Metformin in severe exacerbations of chronic obstructive pulmonary disease: a randomised controlled trial.

BACKGROUND: Severe exacerbations of COPD are commonly associated with hyperglycaemia, which predicts adverse outcomes. Metformin is a well-established anti-hyperglycaemic agent in diabetes mellitus, possibly augmented with anti-inflammatory effects, but its effects in COPD are unknown. We investigated accelerated metformin therapy in severe COPD exacerbations, primarily to confirm or refute an anti-hyperglycaemic effect, and secondarily to explore its effects on inflammation and clinical outcome. METHODS: This was a multicentre, randomised, double-blind, placebo-controlled trial testing accelerated metformin therapy in non-diabetic patients, aged ≥35 years, hospitalised for COPD exacerbations. Participants were assigned in a 2:1 ratio to 1 month of metformin therapy, escalated rapidly to 2 g/day, or matched placebo. The primary end point was mean in-hospital blood glucose concentration. Secondary end points included the concentrations of fructosamine and C reactive protein (CRP), and scores on the COPD Assessment Test and Exacerbations of Chronic Pulmonary Disease Tool. RESULTS: 52 participants (mean (±SD) age 67±9 years) were randomised (34 to metformin, 18 to placebo). All were included in the primary end point analysis. The mean blood glucose concentrations in the metformin and placebo groups were 7.1±0.9 and 8.0±3.3 mmol/L, respectively (difference -0.9 mmol/L, 95% CI -2.1 to +0.3; p=0.273). No significant between-group differences were observed on any of the secondary end points. Adverse reactions, particularly gastrointestinal effects, were more common in metformin-treated participants. CONCLUSION: Metformin did not ameliorate elevations in blood glucose concentration among non-diabetic patients admitted to hospital for COPD exacerbations, and had no detectable effect on CRP or clinical outcomes. TRIAL REGISTRATION NUMBER: ISRCTN66148745 and NCT01247870.

Safety of metformin in patients with chronic obstructive pulmonary disease and type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is commonly associated with chronic obstructive pulmonary disease (COPD). Metformin is a valuable treatment for T2DM, and may offer additional benefits in COPD. However, due to its rare association with lactic acidosis, its safety in COPD is uncertain. We retrospectively identified patients with T2DM who had been admitted to hospital for COPD exacerbations. We compared those who were taking metformin with those who were not, with respect to their lactate concentration (primary endpoint) and survival (secondary endpoint). The study cohort (n = 130) had a mean (±standard deviation) age of 73.0 ± 9.8 years and 47 (36%) were female. Arterial blood gases were recorded in 120 cases: 88 (73%) were hypoxemic, 45 (38%) were in respiratory failure and 33 (28%) had respiratory acidosis. The 51 patients (39%) in the metformin group had a median (interquartile range) lactate concentration of 1.45 mmol/L (1.10-2.05) versus 1.10 mmol/L (0.80-1.50) in the non-metformin group (p = 0.012). Median survival was 5.2 years (95% CI 4.5-5.8) versus 1.9 years (1.1-2.6), respectively (hazard ratio 0.57; 95% CI 0.35-0.94). This remained significant in a multivariate model adjusted for measurable confounders. In conclusion, among patients with COPD at high risk for lactate accumulation, metformin therapy was associated with a minor elevation of lactate concentration of doubtful clinical significance. Metformin was associated with a survival benefit, but this must be interpreted cautiously due to possible effects from unmeasured confounders. Viewed collectively, the results suggest that COPD should not present a barrier to the investigational or clinical use of metformin.

Safety of Metformin in Patients with Chronic Obstructive Pulmonary Disease and Type 2 Diabetes Mellitus.

Type 2 diabetes mellitus (T2DM) is commonly associated with chronic obstructive pulmonary disease (COPD). Metformin is a valuable treatment for T2DM, and may offer additional benefits in COPD. However, due to its rare association with lactic acidosis, its safety in COPD is uncertain. We retrospectively identified patients with T2DM who had been admitted to hospital for COPD exacerbations. We compared those who were taking metformin with those who were not, with respect to their lactate concentration (primary endpoint) and survival (secondary endpoint). The study cohort (n = 130) had a mean (±standard deviation) age of 73.0 ± 9.8 years and 47 (36%) were female. Arterial blood gases were recorded in 120 cases: 88 (73%) were hypoxemic, 45 (38%) were in respiratory failure and 33 (28%) had respiratory acidosis. The 51 patients (39%) in the metformin group had a median (interquartile range) lactate concentration of 1.45 mmol/L (1.10-2.05) versus 1.10 mmol/L (0.80-1.50) in the non-metformin group (p = 0.012). Median survival was 5.2 years (95% CI 4.5-5.8) versus 1.9 years (1.1-2.6), respectively (hazard ratio 0.57; 95% CI 0.35-0.94). This remained significant in a multivariate model adjusted for measurable confounders. In conclusion, among patients with COPD at high risk for lactate accumulation, metformin therapy was associated with a minor elevation of lactate concentration of doubtful clinical significance. Metformin was associated with a survival benefit, but this must be interpreted cautiously due to possible effects from unmeasured confounders. Viewed collectively, the results suggest that COPD should not present a barrier to the investigational or clinical use of metformin.

Dissemination and uptake of a new treatment pathway for paracetamol poisoning in the UK: a survey of healthcare professionals.

AIMS: On 3 September 2012, the UK Medicines and Healthcare Products Regulatory Agency (MHRA) notified healthcare professionals of immediate changes to the intravenous acetylcysteine license terms, altering the treatment pathway for paracetamol poisoning. We sought to evaluate awareness of this amongst healthcare professionals. METHODS: We surveyed doctors, nurses and pharmacists in the 1-12 week period following the implementation date. RESULTS: Forty-four individuals completed the survey in paper form (response rate 86%) and 220 in electronic form (response rate unknown). The resulting sample of 264 individuals was drawn from 41 institutions, and included 143 doctors, 58 pharmacists and 50 nurses. Of these individuals, 157 (59%) were aware of the changes, and 133 (50%) had adopted them in practice. Awareness differed between healthcare professions (P = 0.001) and specialties (P = 0.002). For respondents aware of the changes, the main sources of information were alerts issued internally (reported by 57%), from the MHRA (25%) and from other professional bodies (24%). The proportion of individuals who reported receiving practical implementation instructions (e.g. a protocol) was higher among respondents who had changed their practice than for those who had not (86 vs. 25%, respectively; P < 0.001). CONCLUSIONS: Less than two-thirds of healthcare professionals in specialties managing patients with paracetamol poisoning were aware of important changes to its treatment pathway in the 12 weeks after they took effect, and only half had adopted them in practice. Alternative communication strategies should be explored to improve dissemination of similar information from the MHRA and other medicines regulators in the future.

Determining the volume of toxic liquid ingestions in adults: accuracy of estimates by healthcare professionals and members of the public.

CONTEXT: Ingestion of toxic liquids is common, and the volume ingested is often important for clinical decision-making. However, the accuracy and interpretation of volume estimates in the context of toxicological exposures is poorly characterised in adult practice. OBJECTIVE: To inform the interpretation of volume estimates when expressed in forms commonly encountered in toxicological practice: (1) semi-quantitative volume descriptors, such as 'mouthfuls'; (2) quantitative self-estimates of ingestion volume, for example, millilitres; and (3) estimates of residual volume in containers. METHODS: In the first part of the study, 50 members of the public ingested water in response to requests to take a 'small mouthful', 'large gulp' and 'five mouthfuls'. They estimated the amount ingested, and actual volumes were measured. In part 2, 15 members of the public and 15 healthcare professionals estimated the volumes contained in 12 opaque and transparent bottles. RESULTS: The mean age of participants in part 1 was 37 years, and in part 2 it was 34 years. The mean volume (95% prediction interval) of a 'small mouthful' was 43 (3-137) mL; 'large gulp', 77 (20-168) mL; and 'five mouthfuls', 157 (25-375) mL. The mean error (95% limits of agreement) for self-estimates of ingestion volume was an underestimate of - 52% (- 90% to + 124%). Volume contained in bottles was underestimated by - 5% (- 38% to + 27%). This varied according to the container type (mean difference: opaque, - 10%; transparent, - 1%; P < 0.01) and participant type (members of the public, - 8%; healthcare professionals, - 3%; P = 0.02). CONCLUSIONS: Volume estimates derived from semi-quantitative descriptors are not a reliable basis for clinical decision-making. Self-estimates provided in a quantitative form are inaccurate and prone to underestimation. Estimates of residual volume in containers should be regarded as suspect if the container is opaque. Where clinical decisions hinge on the volume ingested, efforts should be made to quantify this using measurement.