Advanced Electrocardiogram Analysis in the Amitriptyline‐poisoned Pig Treated with Activated Charcoal Haemoperfusion

Coated activated charcoal haemoperfusion (CAC‐HP) does not reduce the plasma concentration in amitriptyline (AT)‐poisoned pigs. The aim of this non‐blinded, randomized, controlled animal trial was to determine if CAC‐HP reduces the pathological ECG changes caused by AT poisoning. Fourteen female Danish Landrace pigs (mean weight 27.7 kg, range 20–35 kg (CAC‐HP) and 24.4 kg, range 18–30 kg (control group, CG), n = 7 in each group) were included. After randomization, the pigs were anaesthetized and intravenously poisoned with AT. The intervention group underwent 4 hr of CAC‐HP plus standard care (oral activated charcoal). Intervention was compared to standard care alone. From each pig, a 12‐lead ECG and haemodynamic variables were obtained at baseline, at full AT loading dose, before and during CAC‐HP. Baseline ECG variables (RR, PR, QRS, QTc, QTp, QTe, TpTe and TpTe/QT) for lead II, v2 and v5 were not significantly different (F = 0.035–0.297, p‐values 0.421–0.919). Differences within groups over time and between groups were tested by anova repeated measures. For all variables, the time‐plus‐group level of significance revealed a p‐value > 0.05. Severe cardiovascular arrhythmias occurred in both groups with 3 in the CAC‐HP group versus 1 incident with premature death in the CG. The attenuating effect of CAC‐HP to orally instilled activated charcoal alone on AT‐induced ECG alterations did not differ significantly. We conclude that the use of modern CAC‐HP as an adjunctive treatment modality in AT‐poisoned pigs is inadequate.