Calcium channel blockers do not enhance increases in plasma potassium after succinylcholine in humans.

STUDY

OBJECTIVE

To determine whether chronic calcium channel blocker therapy exaggerates the rise in plasma potassium concentration ([K+]) after succinylcholine administration.

DESIGN

Prospective clinical study.

SETTING

University and Veterans Affairs hospitals.

PATIENTS: 36 ASA physical status III and IV male patients: 21 patients taking chronic calcium channel blockers and 15 patients not receiving calcium channel blockers, all of whom were scheduled for inpatient surgical procedures with general anesthesia.

INTERVENTIONS: In all patients, anesthesia was induced with high-dose opioids plus a sedative-hypnotic, and intubation was facilitated with 1 to 1.5 mg/kg succinylcholine without nondepolarizing neuromuscular blocker pretreatment.

MEASUREMENTS AND MAIN

RESULTS

Plasma [K+] was measured prior to induction and 1, 3, 5, 8, 11, and 15 minutes after succinylcholine was administered. A modest average peak rise of 0.5 mEq/L in plasma [K+] was observed, but there were no differences between patients who were or were not receiving calcium channel blockers.

CONCLUSIONS

Patients receiving chronic calcium channel blocker therapy are at no greater risk of hyperkalemia after succinylcholine than those not taking such medications.