Background and importance Anaesthetic drugs are vital during surgical procedures to lower patient discomfort but they carry significant risks for adverse events. Regular follow-up of patterns in anaesthetic related adverse drug events (ARAEs) is therefore required.
Aim and objectives To examine ARAE occurrence and trends during procedures (gastro-/colonoscopy (GCS), cardiac ablation (CA)) requiring general anaesthesia in a university hospital.
Material and methods Inclusion criteria were: adult patients undergoing GCS or CA between 1 July 2017 and 30 June 2019. Retrieved procedures were chronologically sorted after which a 10% randomised sample was taken, and stratified according to procedure, age and gender. For each patient, characteristics were retrieved from the medical file, including risk score, home medication (HM), premedication, procedure characteristics (eg, used anaesthetics/antidotes, anaesthesiologist’s experience, timing) and whether ARAEs occurred (oxygen saturation <90%, blood pressure drop ≥20%, bradycardia <45 beats/min and apnoea). Predictors were selected using Spearman analysis, retaining variables with p<0.2, which were then entered in a stepwise backward logistic regression. A times series analysis was done to assess time dependent trends.
Results 1355 CAs and 1475 GCSs were retrieved, leading to 283 (135 CA/148 GCS) procedures selected for analysis, with 44 (15.5%; 37 CA/7 GCS) anaesthesia files incomplete or missing. Most patients experienced at least one ARAE (174/239) with the majority experiencing low blood pressure (169/174), followed by bradycardia (15/174), oxygen desaturation (3/174) and apnoea (1/174). When looking at predictors for any ARAE, use of inhalation anaesthetic (OR 2.74; p=0.024) and midazolam premedication (OR 5.03; p=0.035) were the most important, with opioid HM also showing a trend (OR 7.49; p=0.054). For bradycardia, patients receiving amiodarone/verapamil HM (OR 5.70; p=0.034) or with an inhalation anaesthetic (OR 5.36; p=0.003) had a higher risk, while ACE inhibiting HM increased the desaturation risk (OR 73.32; p=0.046). Regarding low blood pressure and apnoea, no patient or procedure related factors could be found. Time series analysis revealed no time dependent trends in ARAE occurrence or incomplete files.
Conclusion and relevance The impact of ACE inhibitors on ARAEs is well described, with a preprocedural stop suggested. However, long term consequences are not clear. Furthermore, preprocedural midazolam may need to be reviewed, as other measures to decrease anxiety are also effective. Finally, increased attention to anaesthesia documentation is needed.
References and/or acknowledgements
Hollmann, et al. Anesth Analg 2018;127:678–87.
Jlala, et al. Br J Anaesth 2010;104:369–74.
Conflict of interest No conflict of interest