[Lumbar and thoracic epidural anesthesia in children's hospitals in Japan].

A retrospective study of the lumbar and thoracic epidural anesthesia (catheterization) in infants and children younger than 12 years was undertaken in children's hospitals in Japan. Seventeen institutions replied to our questionnaire and 10 institutions experienced these procedures in the year preceding September 1994. The total number of the lumbar and thoracic epidural anesthesia performed was 324, with average of 32.4 +/- 31.1, and maximum of 113 and the minimum of 2. The number of thoracic epidural anesthesia performed was 56 a much smaller figure than that of lumbar anesthesia. Infants younger than 12 months were 23 in both groups. No major complications occurred except a case of infection at the insertion site. The patient had herpes zoster. On the other hand, several institutions cast doubt on the necessity of epidural anesthesia in infants and children. The long-term influence on the developing nervous system should be investigated.

[Effect of sevoflurane and nitrous oxide anesthesia on auditory brainstem responses in children].

The effect of sevoflurane and nitrous oxide anesthesia on the auditory brainstem response (ABR) was studied in 70 infants and children ranging in age between 1 month and 15 years. The latencies in ABR under a non-anesthetic state are no longer in the waves originating from the central portion in younger subjects. This tendency was recognized under ketamine anesthesia as control and sevoflurane and nitrous oxide anesthesia as well. Although nitrous oxide 60% and sevoflurane 2.5% increased the latency of wave V and the interpeak interval I-V significantly in all age groups, the changes were small (0.26 +/- 0.16 msec and 0.23 +/- 0.19 msec). The changes in infants were relatively large compared with elder subjects. These concentrations did not decrease the amplitude of waves I, III and V significantly in any age group. Sevoflurane exerted little influence on ABR, and it would be useful for ABR testing in children.

[Effect of induction methods of pediatric anesthesia on serum myoglobin].

Two hundred and twenty nine children from infancy to middle teens divided into six groups were studied to determine the effect of induction methods of pediatric general anesthesia on serum myoglobin. After the slow induction with nitrous oxide-oxygen-halothane (GOF), the serum myoglobin increased significantly to 1774.7 +/- 4285.8 ng.ml-1 (mean +/- SD) by iv administration of succinylcholine 1 mg.kg-1. This significant increase of serum myoglobin was reduced by pretreatment with d-tubocurarine (dTc) 0.05 mg.kg-1 before administration of succinylcholine. However, it was not reduced by pretreatment with thiopental 3 mg.kg-1. After the rapid induction with thiopental 5 mg.kg-1 and succinylcholine 1 mg.kg-1, the serum myoglobin increased slightly to 387.6 +/- 596.5 ng.ml-1. But this increase in serum myoglobin was stopped by pretreatment with dTc 0.05 mg.kg-1 before the rapid induction. Serum myoglobin was not changed without succinylcholine after the slow induction with GOF. In each group, there was no relation with serum myoglobin and ages or fasciculation. Serum myoglobin was more influenced by the induction methods of pediatric general anesthesia than by ages.

[Study of hypothermic anesthesia--cardiac contractility during hypothermia].

We studied cardiac function during hypothermia, and effects of various methods of anesthesia on hearts taken from guinea pigs which received extracorporeal circulation by Langendorff method. Morphine, fentanyl citrate and halothane were used as anesthetics. Morphine and fentanyl citrate were added to the infusate at the dose of 3 mg.kg-1 or 50 micrograms.kg-1. Halothane 1% was introduced into the infusate by bubbling. Left ventricular peak dp/dt was measured as an index of cardiac contractility. Halothane depressed cardiac contractility most at normal temperature, and this was changed by cooling. Cardiac contractility with both morphine and fentanyl citrate was similar, and showed significant advantage over halothane at 30 degrees C, 25 degrees C and 20 degrees C. Coronary arterial blood flows at 30 degrees C, 25 degrees C and 20 degrees C were in the order of halothane greater than fentanyl citrate greater than morphine. The result suggests that oxygen consumption of myocardium under halothane anesthesia, even during hypothermia is high.

[Treatment of congenital tracheal stenosis. Retrospective study of thirteen cases].

Thirteen cases of congenital tracheal stenosis (CTS) were retrospectively studied in terms of operative indication and treatment. The intratracheal transverse ratio of the stenotic/normal diameter (stenotic ratio, SR) was obtained by chest X-ray, tracheogram or autopsy, as one of the parameters of stenosis. SR ranged from 0.14 to 0.50 (mean 0.35 +/- 0.13 SD). Two cases (SR = 0.14) received tracheal resection and reanastomosis successfully. In three cases with pulmonary artery sling (PAS), PA translocation was performed to release tracheal compression. One (SR = 0.49) had good result but two (SR = 0.20, 0.30) died from respiratory failure (RF) and autopsy revealed PAS. Four cases underwent surgery for congenital heart disease (CHD), 3 (SR = 0.41, 0.46, 0.49) had good results but one (SR = 0.36) died from RF. In four cases medically treated, 3 (SR = 0.40, 0.44, 0.50) improved with growth but one (SR = 0.25) died before operation due to RF and autopsy revealed PAS. When SR greater than or equal to 0.40, cases without PAS improved with conservative treatment, those with PAS improved by PA translocation, and those with CHD tolerated open heart surgery. When SR less than 0.40, tracheal reconstruction is indicated. Cases with PAS would require primary or staged operation of PA translocation + tracheal reconstruction. The most appropriate therapy should be selected on the basis of symptoms, associated diseases and parameter of tracheal stenosis, for instance "SR".

Surgical treatment of congenital distal tracheal stenosis involving the carina.

Untreated congenital stenosis of the distal trachea frequently results in lethal airway obstruction. A 3-year-old boy with segmental stenosis of the distal trachea and a 2-year-old girl with segmental stenosis involving the carina and the right main bronchus were treated successfully with resection and reanastomosis. Operative techniques, anesthetic management, postoperative care, and tracheal growth after anastomosis are discussed.

Total one-stage repair of interrupted aortic arch associated with aortic septal defect and patent ductus arteriosus.

Successful total repair in one stage was performed in a 3-year-old girl who had interrupted aortic arch associated with aortic septal defect and patent ductus arteriosus. Surface-induced deep hypothermia and interrupted perfusion were used. The results of postoperative catheterization and angiocardiographic studies are analyzed, and the literature and results of previous surgical attempts at correction are reviewed.