Intraoperative succinylcholine and the postoperative eye alignment

In 99 patients undergoing strabismus surgery, an intravenous bolus of succinylcholine (Sch) was given after completion of the strabismus procedure. Reliable data were obtained in 53 patients. The interlimbal distance measured at 60 seconds after injection (VR60) was compared to the interlimbal distance at 1 and 6 weeks postoperatively, to evaluate the correlation between the drug-induced eye position under anesthesia and the awake-eye alignment postoperatively. Correlations were highest in patients undergoing symmetric recessions of the medial or lateral recti in primary horizontal strabismus. Confidence intervals of 0.8 to 1.2 were noted for both the esotropia and exotropia groups. Two patients experienced Sch-related complications of masseter spasm and prolonged apnea. Although infrequent, the potential gravity of the complications from Sch use and the currently enjoyed high rate of success in primary strabismus surgery suggest that these formulas not be used clinically. Nonetheless, the high correlations between the drug-induced and awake ocular position provide further support to the premise that the Sch sensitive fibers provide an important motor component to the awake eye position.