Shigeyuki Saito

Intraoperative transesophageal echocardiography for inferior vena caval tumor thrombus in renal cell carcinoma

Background : We investigated the advantages of intraoperative transesophageal echocardiography (TEE) during inferior vena caval tumor thrombectomy in renal cell carcinoma (RCC).

Halothane Minimum Alveolar Anesthetic Concentration and Neuronal Nitric Oxide Synthase Activity of the Dorsal Horn and the Locus Ceruleus in Rats

UNLABELLED There is some evidence of a relationship between nitric oxide and pain control pathways. However, it is still controversial whether nitric oxide synthase (NOS) inhibitors affect minimum alveolar anesthetic concentration (MAC). We examined the effects of 7-nitro indazole (7-NI), a selective neuronal NOS (nNOS) inhibitor, on halothane MAC. With nicotinamide adenine dinucleotide phosphate diaphorase histochemistry, we also investigated the nNOS activity of the dorsal horn and the locus ceruleus in 26 Sprague-Dawley rats. 7-NI (100, 500, 1000 mg/kg intraperitoneally) reduced halothane MAC to 0.34% +/- 0.12%, 0.1% +/- 0.03%, and 0.05% +/- 0.12%, dose dependently (P < 0.01). 7-NI also reduced the number of nicotinamide adenine dinucleotide phosphate diaphorase-positive cells by 20% to 65% (P < 0.05 or 0.01) and the staining intensity of the axons in the locus ceruleus and lumbar and thoracic spinal cord as compared with the control group. 7-NI reduced the MAC observed with halothane anesthesia, which was accompanied by nNOS activity suppression in the spinal cord and the locus ceruleus. Our results support the hypothesis that the nitric oxide signaling pathway is related to MAC. IMPLICATIONS We examined the effects of a selective neuronal nitric oxide synthase inhibitor, 7-nitro indazole, on halothane minimum alveolar anesthetic concentration and measured the nitric oxide synthase activity in the spinal cord and the locus ceruleus of Sprague-Dawley rats using nicotinamide adenine dinucleotide phosphate diaphorase staining method. 7-Nitro indazole decreased both the minimum alveolar anesthetic concentration and neuronal nitric oxide synthase activity.

Effect of intravenous prostaglandin E1 on pial vessel diameters and intracranial pressure in rabbits.

Background: The main advantages of prostaglandin E1 (PGE1) for induced hypotension during neurosurgery include a rapid onset of action, a quick recovery from hypotension, lack of toxicity, maintenance of adequate perfusion to vital organs, and maintenance of cerebral blood flow reactivity to carbon dioxide during hypotension. However, there is no report that shows the effect of PGE1 on cerebral microvessel diameter and only a few data are available that show the effect of PGE1 on intracranial pressure. The aim of this study was to measure cerebral arteriole and venule diameters and intracranial pressure (ICP) during PGE1‐induced hypotension to evaluate whether PGE1 is suitable for neuroanesthesia.

Hyperventilation induced coronary artery spasm during anesthesia for neurosurgery

For patients with intracranial pathology, induced hyperventilation is recommended to reduce intracranial pressure during anesthesia1,2 . But hyperventilation may cause angina and coronary artery spasm in some patients with or even without the presence of coronary artery disease3 8 . We report a case in which coronary artery spasm, probably related with hyperventilation, occurred in a patient without previous history of coronary disease. This, to the best of our knowledge, has never been reported to occur in association with anesthesia for neurosurgery.