[Anesthetic management for a patient with autoimmune hemolytic anemia].

A 69-year-old woman with autoimmune hemolytic anemia (AIHA) received gastric resection and splenectomy under general anesthesia combined with epidural anesthesia. Her blood type had been determined as type A, Rh type CCDee, with anti-e-antibody and anti-pdl-antibody positive as autoantibodies. We applied the technique of hemodilutional autologous transfusion to supplement the blood loss during the operation to prevent hemolysis or occurrence of new antibody after homologous transfusion. We should pay much attention to a patient with AIHA to find signs of peri-operative hemolysis and to give the treatment for hemolysis in early stage. We consider that the hemodilutional autologous transfusion is a useful technique for the anesthetic management of the patient having a rare blood type.

[Effects of melatonin on muscle contractility and neuromuscular blockade produced by muscle relaxants].

Effects of melatonin on muscle contractility and on the blocking properties of succinylcholine and vecuronium were investigated in vitro using phrenic nerve-hemidiaphragm preparations of rats. Melatonin (26-520 microM) alone had almost no effect on the contractility. Melatonin (260 microM) markedly potentiated the block produced by succinylcholine, but melatonin had no effect on the block produced by vecuronium. Because the property of the block produced by succinylcholine is nicotinic receptor desensitization, we consider that melatonin potentiates succinylcholine-induced block with facilitation of the desensitization. These results suggest that melatonin has calcium channel blocking effect.

[Neuromuscular effects of vecuronium d-tubocurarine and succinylcholine in malnourished rat's diaphragm].

The pharmacodynamics of neuromuscular blocking agents in malnutrition have not been well delineated. In the present study, the neuromuscular effects of vecuronium (Vb), d-tubocurarine (d-Tc) and succinylcholine (SCh) in malnutrition were investigated. Male Sprague-Dawley rats aged 7 weeks were divided into malnourished and control groups. One fifth of their usual daily consumption was allowed in the malnourished group for 10 days. The animals were anesthetized and phrenic nerve-hemidiaphragm preparations were dissected. The preparations were placed in an organ bath containing oxygenated Krebs' solution at 37 degrees C. The diaphragms were stimulated through their phrenic nerves with supramaximal stimuli of 0.2 msec at the rate of 0.1 Hz. The responses were measured by an isometric transducer. The 50% and 90% inhibitory concentrations (IC50, IC90) of Vb, d-Tc and SCh were determined form dose-response curves. Body weight was significantly lower in malnourished group than in the control group. IC50 and IC90 of both Vb and d-Tc were significantly higher in the malnourished group than in the control group (P < 0.001). However, IC50 and IC90 of SCh were significantly lower in the malnourished group than in the control group (P < 0.0001). In this study, malnutrition increased resistance to nondepolarizing neuromuscular blocking agent and sensitivity to SCh compared with the control. These results suggest that malnutrition might induce similar changes of acetylcholine receptor which are observed in denervation or burn injury.