Clinical, electrocardiographic, and laboratory findings in children with amitriptyline intoxication.
BACKGROUND
Amitriptyline is one of the major tricyclic antidepressants, and the data on amitriptyline poisoning in children are limited.


OBJECTIVE
To present our experiences with amitriptyline poisoning in children, particularly with regard to its effects on electrocardiogram (ECG) and relation with clinical status.


METHODS
Clinical, laboratory, and electrocardiographic findings in 52 children admitted with amitriptyline poisoning were reviewed. Patients were divided into 2 groups according to age, as 6 years or younger (group A) and older than 6 years (group B).


RESULTS
Mean age was 4.6 +/- 3.0 years. Thirty-one patients were male, and 41 were 6 years or younger. Ingested amitriptyline dose was known in 23 patients (range, 2.3 mg/kg-27 mg/kg). The most frequent findings were lethargy (76.9%), sinus tachycardia (57.7%), and coma (48.1%). Four patients had a history of convulsion. The most common laboratory abnormalities were hyponatremia (26.9%) and leukocytosis (25%). Elevated transaminase levels were observed in 4 patients. In ECG, 11 (22.4%) patients had QTc prolongation and in 4 (8.2%) of them, it was significant. In 4 patients (8.2%), the QRS duration was 100 ms or longer and in 15 patients, the R wave in aVR was 3 mm or longer. The frequencies of clinical, laboratory, and electrocardiographic findings were similar between the 2 age groups (P > 0.05). No clinically apparent arrhythmias were observed. The positive predictive value of a widened QRS was 100% in terms of coma. None of the patients with an R wave in aVR of less than 3 mm developed convulsion; thus, the negative predictive value of an R wave in aVR of 3 mm or longer was 100% in terms of convulsion.


CONCLUSIONS
Amitriptyline poisoning may result in severe toxicity. Frequencies of clinical, laboratory, and ECG findings were similar in the 2 age groups. Amitriptyline overdose results in some ECG changes that can possibly help to predict the results of poisoning. Absence of an R wave in aVR of 3 mm or longer predicts seizures with a high negative predictive value, and a QRS duration of 100 or longer ms predicts coma with a high positive predictive value.
Olgun
Haşim
H
Division of Pediatric Cardiology, Ataturk University, Faculty of Medicine, Erzurum, Turkey. drholgun@hotmail.com
Yildirim
Zuhal Keskin
ZK
Karacan
Mehmet
M
Ceviz
Naci
N
D000293:Adolescent; D000639:Amitriptyline / Q000506:poisoning*; D000929:Antidepressive Agents, Tricyclic / Q000506:poisoning*; D002648:Child; D002675:Child, Preschool; D062787:Drug Overdose; D015716:Electrocardiography, Ambulatory / Q000187:drug effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D053609:Lethargy / Q000097:blood / Q000139:chemically induced* / Q000503:physiopathology; D007964:Leukocytosis / Q000097:blood / Q000139:chemically induced* / Q000503:physiopathology; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D012964:Sodium / Q000097:blood*; D013226:Status Epilepticus / Q000097:blood / Q000139:chemically induced / Q000503:physiopathology; D013616:Tachycardia, Sinus / Q000097:blood / Q000139:chemically induced* / Q000503:physiopathology
D000929:Antidepressive Agents, Tricyclic; D000639:Amitriptyline; D012964:Sodium