Clinical automatic control of neuromuscular blockade

A simple feedback control technique has been used to automatically deliver pancuronium to anaesthetised surgical patients. The dosage rate is automatically adjusted at 10‐second intervals, according to the measured evoked, rectified, integrated electromyogram. When set to demand 80 percent blockade, in 40 patients. the controller maintained blockade at a steady mean level of 72.9 percent (consuming pancuronium at a mean rate of 0.47 μg/kg/minute). The main clinical practical problems involved protection against electrical noise and the need to spend time setting up the equipment.