Cross-sectional study of perioperative drug and allergen exposure in UK practice in 2016: the 6th National Audit Project (NAP6) Allergen Survey

Background: Details of the current UK drug and allergen exposure were needed for interpretation of reports of perioperative anaphylaxis to the 6th National Audit Project (NAP6). Methods: We performed a cross-sectional survey of 356 NHS hospitals determining anaesthetic drug usage in October 2016. All cases cared for by an anaesthetist were included. Results: Responses were received from 342 (96%) hospitals. Within-hospital return rates were 96%. We collected 15 942 forms, equating to an annual caseload of 3.1 million, including 2.4 million general anaesthetics. Propofol was used in 74% of all cases and 90% of general anaesthetics. Maintenance included a volatile agent in 95% and propofol in 8.7%. Neuromuscular blocking agents were used in 47% of general anaesthetics. Analgesics were used in 88% of cases: opioids, 82%; paracetamol, 56%; and non-steroidal anti-inflammatory drugs, 28%. Antibiotics were administered in 57% of cases, including 2.5 million annual perioperative administrations; gentamicin, co-amoxiclav, and cefuroxime were most commonly used. Local anaesthetics were used in 74% cases and 70% of general anaesthetics. Anti-emetics were used in 73% of cases: during general anaesthesia, ondansetron in 78% and dexamethasone in 60%. Blood products were used in ≈3% of cases, gelatin <2%, starch very rarely, and tranexamic acid in ≈6%. Chlorhexidine and povidone-iodine exposures were 74% and 40% of cases, and 21% reported a latex-free environment. Exposures to bone cement, blue dyes, and radiographic contrast dye were each reported in 2–3% of cases. Conclusions: This survey provides insights into allergen exposures in perioperative care, which is important as denominator data for the NAP6 registry.