Background
Little is known about Perioperative Anaphylaxis (PA) in the UK. The 6th national audit project (NAP6) is the first comprehensive review of PA with core results awaited. We present an audit of NHS Lothian PA database from 6/3/2015-15/8/17 following introduction of anaphylaxis boxes (AB). We compare the results with those of an audit preceding AB introduction.

Methods
The database prospectively records the following information from PA events occurring in NHS Lothian: date of reaction, symptoms, treatment, tryptase levels, date and results of allergy testing. Data was compared with results of a 4-year PA retrospective case note audit at Royal Infirmary of Edinburgh completed in 2014.

Results
33 events of PA were recorded (incidence 1:3949). The most common life-threatening features were hypotension (82%) and bronchospasm (70%). Angioedema (6%) and cardiac arrest (3%) were rare. Erythema was often associated (79%) but urticaria was present in only 24%. IV adrenaline was administered in 73% of cases; average dose of 593mcg (10-3150mcg). Secondary management (steroid, antihistamine) was given in 76% and tryptase series taken in 79% of cases. All patients were referred for specialist allergy investigation and testing complete in 85%. Of the triggers identified muscle relaxants (67%) and antibiotics (33%) were most common.

Discussion
Our AB are designed to provide an anaesthetist with everything they would need to manage, investigate and refer PA. Since AB introduction we have seen improvements compared with our initial audit findings; including an increase in compliance with secondary management (56% to 76%), in completion of the tryptase series (67% to 79%) and notably an increase in the completion of testing (11% to 85%). Our incidence of PA is considerably higher than reported elsewhere (1). However, NAP6 baseline survey results recently suggest the incidence in the UK may be even higher; 1:15561. If the incidence found in the NAP6 core project correlate with the baseline survey it may be there is still significant under investigation in NHS Lothian.

Conclusion
We have shown that introduction of AB improves management of PA. At present only 37% of UK anaesthetists have access to AB (1) and our results would support their introduction as a potential recommendation from NAP6.

Reference
1.Kemp.H et al.UK anaesthetists’ perspectives and experiences of severe perioperative anaphylaxis:NAP6 baseline survey. British Journal of Anaesthesia, 2017;119(1):p132-9


10 / Improving the management of perioperative anaphylaxis; Thinking inside the box