Electrocardiographic and haemodynamic alterations caused by three different test solutions of local anaesthetics to detect accidental intravascular injection in children

Background. The aim of this study was to investigate ECG and haemodynamic alterations provoked by a test dose of bupivacaine, epinephrine, and their combination. Methods. Paediatric patients undergoing general anaesthesia were randomized into three groups. After anaesthesia induction and tracheal intubation, 0.2 ml kg 21 (max. 3 ml) of the corresponding test solution was i.v. injected: bupivacaine 0.125% (Group B), bupivacaine 0.125% plus epinephrine 1:200 000 (Group BE), or epinephrine 1:200 000 (Group E). ECG was printed and analysed post hoc. Non-invasive arterial pressure (AP) was measured at 1 and 2 min after test dose injection. Increases in T-wave of ≥25%, in heart rate (HR) of ≥10 beats min 21 , and in systolic AP of ≥15 mm Hg above baseline value were considered a positive result. Results. A total of 105 children aged 0.2 –16 (median 6.8) yr were enrolled. Test dose injection provoked T-wave elevation in 0%, 85%, and 89% of patients in Groups B, BE, and E, respectively. A positive increase in HR was found in 0%, 68%, and 76%. A positive increase in AP at 1 min was found in 0%, 88%, and 94% and at 2 min in 0%, 42%, and 59%. A decrease in HR of ≥10 beats min 21 was observed in 6%, 76%, and 69%. Alterations in T-wave and HR were significantly influenced by age. Conclusions. ECG and haemodynamic alterations after i.v. injection of a local anaesthetic test dose were significantly influenced by epinephrine. T-wave elevation, increase in AP, and changes in HR are highly reliable variables, particularly when age is taken into account.