No abstract available.
Child* ; Humans ; Pheochromocytoma*

BACKGROUND: The purpose of this prospective study is to define the effect of cardiopulmonary bypass (CPB) on the concentration of thyroid hormones and metabolites. METHODS: Blood samples were obtained from 15 patients undergoing open heart surgery at 1) pre-induction, 2) after heparinization, 3) during CPB, 4) 2 hours after CPB, 5) 24 hours after CPB and 6) 48 hours after CPB. Thyroid stimulating hormone, albumin, thyroxine (T4), free thyroxine (FT4), triiodothyronine (T3), free triiodothyronine (FT3) and reverse T3 (T3) were measured. RESULTS: Concentration of T3 significantly decreased after infusion of heparin and maintained at the decreased level until postbypass 24 hours. Concentration of FT3 significantly increased after heparin administration but maintained at a control level during CPB and decreased after postbypass 24 , 48 hours (p<0.05). Reverse T3 increased at 24 and 48 hours after CPB (p<0.05). Thyroxine decreased during CPB and return to control level after CPB. Free thyroxine did not change significantly. Thyroid stimulating hormone was significantly depressed at 24 hours after CPB (p<0.05). CONCLUSIONS: This result suggest that the thyroid function is depressed until 48 hours after CPB and it seems to be associated with abnormal metabolism of thyroid hormones.
Cardiopulmonary Bypass ; Heart* ; Heparin ; Humans ; Metabolism ; Prospective Studies ; Thoracic Surgery* ; Thyroid Gland* ; Thyroid Hormones ; Thyrotropin ; Thyroxine ; Triiodothyronine

Ketamine hydrochloride(ketamine) is a non-barbiturate anesthetic agent chemically designated as dl-2-(0-chlorophenyl)2-(methylamino)-cyclohexanone hydrochloride. Ketamine anesthesia has been found distinctively different from that induced by conventional anesthetic agents, as it provides profound analgesia without significant impairment of respiratory function or stimulation of cardiovascular activities thus avoiding hypotension and are preserved the protective pharyngeal and laryngeal reflexes. In addition, ketamine appears to have muscle relaxation properties. This latter clinical finding, however has not been experimentally substantiated since few reports have appeared on the effect of ketamine on muscle relaxation. The present study therefore, was undertaken to determine whether this agent affects the muscle activity during d-tubocurarine block. The experiment was performed on sixteen rabbits weighing 1.8 to 2.5kg and these were divided into two groups; eight rabbits for control and eight for th study group. All animals were intubated through a tracheostomy under general anesthesia with nembutal 40mg/kg given intravenously. Respiration was controlled by means of a Harvard animal respirator. The body temperature was kept at 35 degrees C to 36 degrees C with a thermo-blanket. The common peroneal nerve and anterior tibial muscle was exposed and the nerve stimulator was applied to the nerve muscle preparation. The twhitch height of the muscle contraction was recorded on a biophysiograph through the force displacement transducer. The common peroneal nerve was stimulated supramaximally using a single twitch, square wave of 0.2 msec duration at a frequency of 0.1Hz once every 10 seconds. The degree of neuromuscular block following intravenous injection of d-tubocurarine 1mg/kg was measured in the control group. And in the study group ketamine 5mg/kg was administered intravenously when 25% of twitch height of muscle contraction was obtained spontaneously after the intravenous injection of d-tubocurarine 1mg/kg. The changes of the twitch height of muscle contraction and the time of spontaneous recovery in the study group were compared with those of the control group. The results were as follows: 1) The times and degree of maximal single twitch depression were obtained at 194.8sec and 87.3% in the control group and were at 197.5 sec and 87.8% in study group. No significant difference was observed. 2) Recovery index of the control group was 1,560.0 sec and recovery index of the study group was markedly prolonged to 2,387.5 sec(53.0% prolongation). 3) Mean decrease of single twitch height was 8.8% soon after the intravenous ketamine 5mg/kg when 25% of twitch height was obtained after the intravenous d-tubocurarine 1mg/kg in the study group.
Rabbits ; Animals

No abstract available.
Myelitis, Transverse*

Patients vary markedly in their responses to d-tubocurarine chloride. Despite an attempt to diminish the variation in responses to relaxants by standardizing experimental techniques, anesthetic concentration kept constant, acid-base status kept constant, premedication omitted, dosage calculated in terms of mg/sq meter body surface, the marked variation was found to persist. The dose related neuromuscular blocking effect of d-tubocurarine chloride was investigated using a rabbit common peroneal nerve anterior tibial muscle preparation. All experimental rabbits tracheas were intubated through tracheostomy under general anesthesia with Nembutal 40 mg/kg intravenously. Reapiration was controlled by a Harvard animal respirator. The body temperature was kept at 35-37 degrees C by a thermoblanket. The degree of neuromuscular block following intravenous d-tubocurarine chloride was measured by single twitch response. The common peroneal nerve was stimulated supramaximally using a square waves of 0. 2 msec duration at a frequency of 0.1 Hz, and each stimulus was repeated once every 10 seconds. The ratio of the twitch height was calculated. The results were as follows: 1) No neuromuscular blocking effect was observed with 0.1 mg/kg of intravenous d-tubocu- rarine chloride. 2) 100% of neuromuscular blocking effect was observed with more than 1mg/kg of intravenous d-tubocurarine chloride. This is 5 to 10 times higher than the human dose. 3) Dose related prolonged neuromuscular blocking effect was observed from d-tubocurarine chloride in rabbits.
Anesthesia, General ; Animals ; Body Temperature ; Humans ; Muscle, Skeletal ; Neuromuscular Blockade* ; Pentobarbital ; Peroneal Nerve ; Premedication ; Rabbits* ; Trachea ; Tracheostomy ; Tubocurarine ; Ventilators, Mechanical

The effect of nitrous oxide on endotracheal tube cuff pressure was measured during N2O-O2-halothane anesthesia. Intracuff pressure was increased in a time-related fashion up to 150 minutes. Thereafter no significant increase was observed, The other hand, there is no endotracheal tube cuff pressure change during O2-halothane anesthesia. These findings demonstrate that nitrous oxide has the capacity to diffuse into Portex endotracheal tube cuffs in significant volumes and may result in increased intracuff pressure, and in O2-halothane anesthesia, the nitrogea in the cuff was diffused out from the cuffs.
Anesthesia ; Anesthesia, Inhalation* ; Hand ; Inhalation* ; Nitrous Oxide

The history of muscle relaxants is fascinating, and their use for clinical applications has been accepted. Depolarizing drugs can produce a non-depolarizing type of neuromuscular block. Decamethonium produces a nondepolarizing block in the isolated rabbit lumbrical muscle. Electromyographic studies of the hand muscles in man have demonstrated that a dual block will be produced with doses of succinylcholine varying from 500 to 1,500 mg (initially a delpolarizing block and subsequently a non-depolarizing block exists). The common peroneal nerve in the rabbit knee was stimulated by a "train of four" method (Ali et al) repeated intermittently. The muscle response with the "train of four" method to intravenous succinylcholine chloride (1 mg/kg) in the rabbit was recorded and analysed after a single injection and repeated intravenous injections of succinylcholine chloride 1 mg/kg. Result were as follows: 1) Time after the "train of four" to depression of muscle twiteh of 25, 50, 75 & 100% was 128. 2, 135. 3, 142. 8 and 159 seconds respectively. 2) Recovery index of a single intravenous injection of succinylcholine chloride 1 mg/kg was observed as 3 minutes and 14 seconds. 3) A depolarizing form of "train of four" response to the first succinylcholine chloride injection 1 mg/kg was observed and, a non-depolarizing form of "train of four" response to the second dose of succinylcholine chloride 1 mg/kg was observed definitely.
Depression ; Hand ; Injections, Intravenous ; Knee ; Methods ; Muscles ; Neuromuscular Blockade ; Peroneal Nerve ; Rabbits* ; Succinylcholine

No abstract available.
Rhizotomy* ; Scoliosis*

No abstract available.

No abstract available.
Anesthesia, General* ; Humans ; Infant, Low Birth Weight* ; Infant, Newborn ; Pulmonary Atelectasis*