Management of unexpected coronary artery spasm in an asymptomatic patient during anaesthesia.

We report a case of life-threatening arrhythmia that was not predicted before surgery. Pulse-less ventricular tachycardia and ventricular fibrillation occurred during surgery without any changes in heart rate and blood pressure, and cardiac massage was required to maintain circulation. Although no organic stenosis was found in either the right or left coronary arteries, post-surgical angiographic examination revealed severe vasospastic angina induced by intra-luminal administration of acetylcholine. Anaesthesia with a high dose of fentanyl and vasodilators prevented the recurrence of life-threatening arrhythmia. Vasospastic angina attacks are difficult to predict with the preoperative examination routinely employed.

[Evaluation of efficiency of ACD-CPR and STD-CPR; a multi-institutional study].

We compared the efficacy of ACD-CPR and STD-CPR based on 64 multi-institutional reports. No significant differences were observed in the rate of restoration of spontaneous circulation (ROSC) and in cardiopulmonary parameters during CPR using the two methods. There were 5 cases in which cardiopulmonary parameters improved after switching from STD-CPR to ACD-CPR and, eventually, in two of them spontaneous circulation was restored. In the ROSC cases of both groups, ETCO2 and values of SpO2, PaO2, and systolic BP at 30 minutes were higher than those of non-ROSC cases. ETCO2 never exceeded 20 mmHg in the non-ROSC cases, but it was higher in the ROSC cases. ACD-CPR is a good choice when trained persons are present or when extra hands are available to continue the CPR.

[Changes in isolated ciliary muscle caused by repeated instillation of carbachol ointment in rabbits and effect of topically applied amlexanox].

PURPOSE: We investigated changes in ciliary muscle caused by continual contraction in rabbits and evaluated the efficacy of topically applied amlexanox, which relaxes the ciliary muscle, on such changes. SUBJECTS AND METHODS: After topical application of carbachol ointment 5 times daily for 2 weeks, the contractile responses of isolated ciliary muscles to carbachol were measured isometrically, and the ciliary smooth muscle fibers were stained with phosphotungstic acid and hematoxylin and observed histologically. 1% amlexanox solution was instilled 5 minutes before every instillation of carbachol ointment. RESULTS: Repeated topical carbachol ointment caused decreases in both contractile responses of isolated ciliary muscles to carbachol and number of ciliary smooth muscle fibers stained by phosphotungstic acid and hematoxylin. Amlexanox inhibited these changes. CONCLUSION: We found that continual contraction of the ciliary muscle caused functional and histological changes in it. These changes are thought to occur in some diseases which cause excessive contraction of the ciliary muscle. Topical amlexanox might be useful for these diseases.

[Effects of intravenous nicardipine, prostaglandin E1, nitroglycerin, sodium nitroprusside, and epidural lidocaine on hepatic and renal blood flow during hypotensive anesthesia].

We studied the effects of intravenous nicardipine (NIC), prostaglandin E1 (PGE1), nitroglycerin (TNG), sodium nitroprusside (SNP) and epidural lidocaine (LID) on hepatic and renal blood flow during general anesthesia (nitrous oxide-oxygen-sevoflurane) in 46 female patients undergoing unilateral total hip arthroplasty. During operations, hepatic blood flow, glomerular filtration rate, renal plasma flow, and renal tubular injury were measured by R 15 ICG (15 minutes retention rate of indocyanine green), CCR (creatinine clearance), CPAH (para-aminohippuric acid clearance), and urinary excretion of NAG and beta 2-microglobulin. Significant elevation of R 15 ICG was observed in the hypotensive state in the TNG group and the elevation of R 15 ICG indicates that blood flow to the liver has decreased during hypotensive anesthesia. Urine volume in the PGE1 group was larger than that in the TNG, SNP or LID group. CCR in the PGE1 group was larger than that in the NIC, TNG or SNP groups. CPAH in the PGE1 group was larger than that in the SNP or LID group. The value of urine NAG in the TNG group was larger than that in the NIC or PGE1 group. The value of urine beta 2-microglobulin in the NIC group was larger than that in the PGE1 or SNP group. The results of urine volume, CCR, CPAH, urine NAG, and urine beta 2-microglobulin indicate that blood flow to the kidneys was greater in the PGE1 group as compared to other groups. This study indicates that prostaglandin E1 is the best hypotensive drug for hepatic and renal blood flow during hypotensive anesthesia.

Dexamethasone changes brain monoamine metabolism and aggravates ischemic neuronal damage in rats.

BACKGROUND: Glucocorticoids have been reported to aggravate ischemic brain damage. Because changes in the activities of various neuronal systems are closely related to the outcome of ischemic damage, the authors evaluated the effects of dexamethasone on the monoaminergic systems and ischemic neuronal damage. METHODS: The right middle cerebral artery was occluded for 2 h, and the tissue concentrations of monoamines and their metabolites were determined in the cerebral cortex and the striatum of rats. The turnover of 5-hydroxytryptamine was compared in animals injected with saline and those injected with dexamethasone twice (2 mg/kg in each injection) by evaluating the probenecid-induced accumulation of 5-hydroxyindoleacetic acid. The turnovers of norepinephrine and dopamine were estimated from the alpha-methyl-p-tyrosine-induced depletion of norepinephrine and dopamine, respectively. The effect of dexamethasone on the infarct volume was evaluated by triphenyltetrazolium chloride stain in rats subjected to 2 h of occlusion. RESULTS: Dexamethasone did not affect the cortical 5-hydroxytryptamine or 5-hydroxyindoleacetic acid contents. However, it suppressed the turnover of the cortical 5-hydroxytryptamine on both sides. Dexamethasone reduced the turnover of the striatal 5-hydroxytryptamine and facilitated the dopamine turnover. In rats subjected to 2 h of occlusion and 2 h of reperfusion, the infarct volume was 10.5 times greater in the group that received dexamethasone than in the animals that received saline. CONCLUSIONS: Dexamethasone suppresses the inhibitory serotonergic system and facilitates the excitatory dopaminergic system in the rat telencephalon. This may be a mechanism by which dexamethasone aggravates ischemic neuronal injury.

Ischemic preconditioning suppresses the noradrenaline turnover in the rat heart.

OBJECTIVE: The mechanism by which ischemic preconditioning protects the heart is presumed to be related to the reduction of energy consumption during a subsequent myocardial infarction. Since the sympathetic nervous system enhances cardiac function and energy consumption, we investigated the relation between ischemic preconditioning and the turnover rate of noradrenaline (NA) in the rat heart. METHODS: The effect of 3 cycles of 5-min occlusions of the rat left coronary artery on changes in arterial blood pressure and heart rate provoked by a subsequent 30 min of ischemia were examined until 60 min after reperfusion. The effect of 3 cycles of occlusions on the infarct size was also evaluated 60 min after reperfusion by comparing the infarcted area with the area at risk in these animals (6 per preconditioned and sham-operated group). The tissue concentration of NA during sustained ischemia was determined in the left ventricle, the intraventricular septum, and the right ventricle in the preconditioned and sham-operated groups. Changes in the turnover rate of NA after 3 cycles of occlusions were also evaluated by assessing the alpha-methyl-p-tyrosine-induced depletion of NA (n = 7 per group). RESULTS: A series of transient occlusions reduced the infarct size 60 min after a sustained ischemia for 30 min. Arterial pressure and heart rate were not affected. The concentration of NA was decreased in the left ventricle 60 min after the onset of sustained ischemia in both the preconditioned and sham-operated groups. The treatment with alpha-methyl-p-tyrosine decreased the NA concentration in all regions of the heart in the sham-operated group after 60 min. However, the treatment with alpha-methyl-p-tyrosine did not deplete the NA concentration in both the occluded and nonoccluded regions in the preconditioned group. CONCLUSIONS: Transient ischemia ameliorated the heart injury induced by a subsequent sustained ischemia, as assessed histologically. The activity of the sympathetic nervous system in all regions of the heart was reduced by transient ischemia in the left coronary vascular bed. These findings suggest that the inhibition of the sympathetic nervous system by the treatment of ischemic preconditioning takes part in the cardiac protection.

An analysis of flow volume curves during artificial ventilation.

Expiratory flow-volume curves during artificial ventilation (FV-av) were analyzed in 48 patients undergoing general anesthesia. They were divided into 4 groups according to preoperative respiratory disorders; obstructive type (group 1), restrictive type (group 2), small airway disease (group 3) and normal control (group 4). Expiratory flow rates and volumes during artificial ventilation were plotted on an X-Y recorder to calculate V50/V25, mean time constant ratio (MTCR), obstructive index (OI) and slope ratio (SR). FV-av values were compared among groups. FV-av values in groups 2 were significantly higher than those in group 4. The values in group 1 and those in group 3 were not significantly different from those in group 4. FV-av values may reflect restrictive respiratory dysfunctions but they are not sensitive enough to detect obstructive lung disease.