Feeling the heat!
UK heatwaves are becoming more frequent due to anthropogenic climate change. July 2023 was globally the hottest month on record, with the temperature exceeding the long-term average by 1.8°C, topping the previous 2021 record by 0.36°C. Across Europe, extreme temperatures have led to devastating wildfires, impacting on people's health, the environment, and economies.
Previous studies have identified adverse impact on human health and reported an increased risk of mortality associated with the heat; this is already a public health concern. Emergency department presentations and hospital admissions provide an indication of total demand for health services during heat events; however, it is postulated that ambulance data can provide a more sensitive indication of demand.
This systematic review related to ambulance service use, heat, and heatwaves, with an aim to estimate the impact on all-cause and cause-specific ambulance dispatches. The protocol was registered through PROSPERO: CRD42022296556. PubMed, Embase, CINAHL, Scopus, ProQuest, and Web of Science were searched for English language papers, 2011–2022, using terms (i) a heat term, (ii) an ambulance term (iii) a health term. In total, 3628 papers were identified; following screening n=48 studies were reviewed. The Newcastle-Ottawa Scale was used to assess quality, four studies reached high quality and ten were eligible for meta-analysis.
The studies reviewed suggested a higher risk of ambulance dispatches associated with heat or heatwaves. For each 5°C increase in mean temperature, the risk of ambulance dispatches increased for all causes (7%) and for cardiovascular diseases (2%). No association was identified between heat and the risk of ambulance dispatches for respiratory diseases. For heatwaves, defined by Excess Heat Factor, increases were identified in the risk of ambulance dispatches at low intensity (6%), severe (7%), and extreme heatwaves (18%). For heatwaves defined by the incorporation of intensity and duration indicators, increases in the risk of ambulance dispatches were identified relatively for mild (2%) and very intense (3%) heatwaves.
Ticking the box when managing the serious trauma patient
Severe trauma represents a human and economic challenge and remains the leading cause of death in people under 40 years of age. Due to a combination of improved prehospital management and rapid and appropriate referral to specialised centres, 30-day mortality has reduced by around 50%. However, despite protocolisation of the management of severe trauma, errors attributable to human factors persist.
This prospective before-and-after study took place in a French mobile emergency and resuscitation service. This emergency medical services system comprises a driver, a nurse and an emergency physician and so is different to the UK model. The study had two phases. In phase I, the checklist was filled in by the nurses after the patient had been taken to hospital, meaning that the checklist could not be used to modify management. In phase II, the checklist was completed while the patient was being transported to the hospital, thus allowing potentially omitted procedures to be performed. The primary outcome was the number of checklist items not completed during each study period.
There were 116 patients included in phase I, and 63 in phase II, although 11 patients in phase II were not managed with the support of the checklist. The overall omission rate of checklist items was significantly lower with the checklist (17%) than without (25%) (p=0.02). Perhaps, unsurprisingly, the trend of omission increased alongside the Injury Severity Score (ISS). For patients with an ISS of ≥25, an omission rate of 30% was recorded without the checklist versus 15% with checklist (p=0.03) A majority of doctors and nurses who used the checklist considered that it should be made compulsory (82% and 67% respectively).
The study has a number of limitations that impact its generalisability, but it provides some good evidence for further evaluations to take place.