Almost a fifth of hospitals in the UK were forced to cancel operations during the three days in July last year when temperatures soared highest, research suggests. The findings, published in a letter to the British Journal of Surgery, are based on surveys of surgeons, anaesthetists and critical care doctors who were working during the peak of last year’s heatwave, from 16-19 July, when temperatures reached as high as 40C in some parts of the country. The researchers received 271 responses from 140 UK hospitals, with respondents from nearly one in five hospitals (18.5%) reporting that elective surgeries had been cancelled as a result of the heatwave. A further third (35.1%) of hospitals would have had to cancel surgery had the high temperatures continued, the findings revealed. This was because NHS buildings were not set up to withstand dangerously high temperatures, the researchers said. Other factors that were found to have contributed to the cancellations included staff shortages (reported by 35.8% of respondents), unsafe theatre environments (30.3%), and bed shortages (22.1%). In addition, the respondents said surgical services were poorly prepared for heatwaves, with 41% of operating theatres having no means to control ambient temperature, while more than a third (35.4%) reported making changes to maintain routine surgical activity during the period. These included delayed discharge of high-risk patients, changes to surgical teams, selecting lower-risk patients to have surgery, and restricting surgical activity to day cases. Other measures included longer staff breaks, extra fluids given to patients, and surgeries earlier in the morning when temperatures were lower. James Glasbey, a National Institute for Health and Care Research doctoral research fellow in global surgery at the University of Birmingham, and co-author of the letter, said: “Even short heatwaves may result in widespread disruption to surgical services in the UK. “The likelihood of extreme weather events is growing – we could find ourselves in both a ‘winter’ and ‘summer’ stress situation within the next few years. “As hospitals tackle post-Covid surgery backlogs, they must consider how to safeguard against further climate change-related disruption to the delivery of surgical services. “This should be included in the preparation of ‘summer pressure’ plans to improve the resilience of elective surgery services.”