Modelling the economic constraints and consequences of anaesthesia associate expansion in the UK National Health Service: a narrative review.

Shortages in the physician anaesthesia workforce have led to proposals to introduce new staff groups, notably in the UK National Health Service (NHS) Anaesthesia Associates (AAs) who have shorter training periods than doctors and could potentially contribute to workflow efficiencies in several ways. We analysed the economic viability of the most efficient staffing model, previously endorsed by both the UK Royal College of Anaesthetists and the Association of Anaesthetists, wherein one physician supervises two AAs across two operating lists (1:2 model). For this model to be economically rational (something which neither national organisation considered), the employment cost of the two AAs should be equal to or less than that of a single supervisor physician (i.e. AAs should be paid <50% of the supervisor's salary). As the supervisor can be an autonomous specialty and specialist (SAS) doctor, this sets the economically viable AA salary envelope at less than £40,000 per year. However, we report that actual advertised AA salaries greatly exceed this, with even student AAs paid up to £48,472. Economically, one way to justify such salaries is for AAs to become autonomous such that they eventually replace SAS doctors at a lower cost. We discuss some other options that might increase AA productivity to justify these salaries (e.g. ≥1:3 staffing ratios), but the medico-political consequences of each of them are also profound. Alternatively, the AA programme should be terminated as economically nonviable. These results have implications for any country seeking to introduce new models of working in anaesthesia.

Rates of Bile Acid Diarrhoea After Cholecystectomy: A Multicentre Audit.

INTRODUCTION: Bile acid diarrhoea (BAD) can occur due to disruption to the enterohepatic circulation, e.g. following cholecystectomy. Post-cholecystectomy diarrhoea has been reported in 2.1-57.2% of patients; however, this is not necessarily due to BAD. The aim of this study was to determine the rates of bile acid diarrhoea diagnosis after cholecystectomy and to consider investigation practices. METHODS: A retrospective analysis of electronic databases from five large centres detailing patients who underwent laparoscopic cholecystectomy between 2013 and 2017 was cross-referenced with a list of patients who underwent 75SeHCAT testing. A 7-day retention time of <15% was deemed to be positive. Patient demographics and time from surgery to investigation were collected and compared for significance (p < 0.05). RESULTS: A total of 9439 patients underwent a laparoscopic cholecystectomy between 1 January 2013 and 31 December 2017 in the five centres. In total, 202 patients (2.1%) underwent investigation for diarrhoea via 75SeHCAT, of which 64 patients (31.6%) had a 75SeHCAT test result of >15%, while 62.8% of those investigated were diagnosed with bile acid diarrhoea (BAD). In total, 133 (65.8%) patients also underwent endoscopy and 74 (36.6%) patients had a CT scan. Median time from surgery to 75SeHCAT test was 672 days (SD ± 482 days). DISCUSSION/CONCLUSION: Only a small proportion of patients, post-cholecystectomy, were investigated for diarrhoea with significant time delay to diagnosis. The true prevalence of BAD after cholecystectomy may be much higher, and clinicians need to have an increased awareness of this condition due to its amenability to treatment. 75SeHCAT is a useful tool for diagnosis of bile acid diarrhoea.

Enzyme-linked oxygen sensing by potassium channels.

The ability of ion channels to respond to an acute perturbation in oxygen tension is a widespread phenomenon, which encompasses many of the major ion channel families. Integral to the ability of several ion channels to respond to acute hypoxic challenge is modulation by upstream enzymatic reactions, suggesting that many ion channels sense oxygen via enzyme-linked processes. Several enzyme-linked oxygen sensing systems have been proposed, including nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-dependent production of hydrogen peroxide, hemoxygenase-dependent generation of carbon monoxide, adenosine monophosphate (AMP) kinase-dependent channel phosphorylation, and src-Lck protein tyrosine kinase, via a currently undetermined mechanism. Each of these enzymes has been shown to endow specific ion channels with the ability to respond to changes in oxygen, with hypoxia exclusively evoking channel inhibition. This article reviews these proposed mechanisms and presents new insights into how one system, hemeoxygenase-2, confers oxygen sensitivity to large conductance, voltage- and calcium-activated potassium channels.