Controlled succinylcholine infusion in a patient receiving echothiophate eye drops

Area of Science:

• Anesthesiology
• Pharmacology
• Biochemistry

Background:

• Glaucoma treatment with echothiophate eye drops can inhibit plasma cholinesterase.
• Reduced plasma cholinesterase activity can prolong neuromuscular blockade from succinylcholine.
• Succinylcholine is a commonly used neuromuscular blocking agent in anesthesia.

Purpose of the Study:

• To assess the safety and efficacy of a controlled succinylcholine infusion in a patient with reduced plasma cholinesterase activity.
• To determine the required dosage of succinylcholine for intubation and maintenance in this patient population.
• To evaluate the recovery profile of neuromuscular transmission after succinylcholine infusion cessation.

Main Methods:

• A controlled infusion of succinylcholine was administered to a 69-year-old male patient undergoing elective surgery.
• Neuromuscular blockade was monitored by measuring the force of contraction of the adductor pollicis muscle.
• Plasma cholinesterase activity was measured and found to be 62% below normal.

Main Results:

• Only 9.5 mg of succinylcholine was needed for tracheal intubation.
• A maintenance infusion rate of 1.1 mg/min was sufficient.
• Recovery of neuromuscular transmission was rapid and uneventful after stopping the infusion.

Conclusions:

• Muscle relaxation with succinylcholine infusion can be safely achieved in patients with decreased plasma cholinesterase activity.
• Close monitoring of neuromuscular function is crucial for safe administration.
• The enzyme was qualitatively normal despite significantly reduced activity.