Introduction: Screening for occult disease using laboratory testing prior t
o electroconvulsive therapy (ECT) is a common practice with little empirica
l support. Method: In a pre-ECT and post-ECT sample of 73 and 562 (respecti
vely) patients evaluated for ECT, the utility of the electrocardiogram, ser
um sodium, serum potassium, serum creatinine, chest radiograph, hemoglobin
level. and white blood cell count was examined. Results and Discussion: Rev
iewing the electrocardiogram and measuring sodium and potassium levels prio
r to the administration of ECT appear to be useful screening tests because
they detect correctable unexpected conditions that are relevant to the risk
of the procedure. Hemoglobin and white blood cell count abnormalities did
not influence the administration of ECT or predict ECT complications. An ab
normal creatinine level or abnormal chest radiograph prior to the administr
ation of ECT predicted a poor medical prognosis that appeared largely unrel
ated to the administration of ECT.