ABSTRACT
BACKGROUND: patients undergoing electroconvulsive therapy (ECT) often receive succinylcholine as part of the anesthetic procedure. The duration of action may be prolonged in patients with genetic variants of the butyrylcholinesterase enzyme (BChE), the most common being the K- and the A-variants. The aim of the study was to assess the clinical significance of genetic variants in butyrylcholinesterase gene (BCHE) in patients with a suspected prolonged duration of action of succinylcholine after ECT. METHODS: a total of 13 patients were referred to the Danish Cholinesterase Research Unit after ECT during 38 months. We determined the BChE activity and the BCHE genotype using molecular genetic methods, the duration of apnea, time to sufficient spontaneous ventilation and whether neuromuscular monitoring was used. The duration of apnea was compared with published data on normal subjects. RESULTS: in 11 patients, mutations were found in the BCHE gene, the K-variant being the most frequent. The duration of apnea was 5-15 min compared with 3-5.3 min from the literature. Severe distress was noted in the recovery phase in two patients. Neuromuscular monitoring was used in two patients. CONCLUSION: eleven of 13 patients with a prolonged duration of action of succinylcholine had mutations in BCHE, indicating that this is the possible reason for a prolonged period of apnea. We recommend objective neuromuscular monitoring during the first ECT.
Subject(s)
Apnea/chemically induced , Apnea/genetics , Butyrylcholinesterase/genetics , Electroconvulsive Therapy , Mutation/physiology , Neuromuscular Depolarizing Agents/adverse effects , Succinylcholine/adverse effects , Adult , Aged , Anesthesia , Anesthesia Recovery Period , Dose-Response Relationship, Drug , Female , Genotype , Humans , Male , Middle Aged , Monitoring, Physiologic , Mutation/genetics , Respiratory Mechanics/physiology , Retrospective StudiesABSTRACT
OBJECTIVE: The present study investigated whether the nitric oxide (NO) system is involved in cyclosporin A (CsA)-induced changes in cardiovascular and renal function in man. SUBJECTS AND METHODS: Ten healthy volunteers were investigated twice--with and without intake of a single dose of CsA (8 mg/kg). N(G)-monomethyl-L-arginine (L-NMMA; 3 mg/kg) was injected 4 h after study start on each day. RESULTS: There was no change in glomerular filtration rate (GFR) on the day without CsA. CsA alone did not change GFR, but after L-NMMA injection, GFR decreased significantly from 101 +/- 4 to 91 +/- 4 ml/min. L-NMMA increased renal vascular resistance with no difference between the two study days. CsA increased significantly the diastolic blood pressure (BP) by 8 +/- 2% and the heart rate (HR) by 30 +/- 4%, without changes in cardiac output L-NMMA further increased BP by around 8%, and decreased HR by 11% and cardiac output by 20% on both study days. L-NMMA decreased urinary flow rate by around 25% and renal sodium clearance from 1.1 to approximately 0.6 ml/min on both study days. CsA decreased plasma renin significantly and increased the urinary excretion rate of prostaglandin E2 (PgE2), 6-keto-prostaglandin F1alpha (6-keto-PgF1alpha) and thromboxane B2(TxB2) when compared to the control day. The urinary excretion rate of NOx and cGMP declined gradually on the control day. In contrast, there was a minor, non-significant increase in NOx and cGMP excretion after CsA, followed by a decrease (29 +/- 2 and 16 +/- 4%, respectively) after L-NMMA in parallel with the decrease in GFR. CONCLUSION: The present findings suggest that NO does not play a major role during acute CsA-induced changes in cardiovascular function and renal haemodynamics in man. Renal NO synthesis, however, may attenuate the acute CsA-induced decrease in GFR.
