Anesthesia and analgesia
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Anesthesia and analgesia · Apr 2000
Pediatric evaluation of the bispectral index (BIS) monitor and correlation of BIS with end-tidal sevoflurane concentration in infants and children.
The bispectral index (BIS) has been developed in adults and correlates well with clinical hypnotic effects of anesthetics. We investigated whether BIS reflects clinical markers of hypnosis and demonstrates agent dose-responsiveness in infants and children. In an observational arm of this study, BIS values in children undergoing general anesthesia were observed and compared with similar data collected previously in a study of adults. In a second arm of the study, a range of steady-state end-tidal concentrations of sevoflurane was administered and corresponding BIS documented. Data were examined for differences between infants (0-2 yr) and children (2-12 yr). No difference was seen in BIS values in children before induction, during maintenance, and on emergence compared with adult values. There was no difference in BIS between infants and children at similar clinical levels of anesthesia. In children and infants, BIS was inversely proportional to the end-tidal concentration of sevoflurane. The sevoflurane concentration for a BIS = 50 (95% confidence interval) was significantly different: 1. 55% (1.40-1.70) for infants versus 1.25% (1.12-1.37) for children. Although validation with specific behavioral end points was not possible, BIS correlated with clinical indicators of anesthesia in children as it did in adults: as depth of anesthesia increased, BIS diminished. BIS correlated with sevoflurane concentration in infants and children. The concentration-response difference between infants and children was consistent with data showing that minimum alveolar concentration is higher in children less than 1 yr of age. ⋯ The use of bispectral index (BIS) during general anesthesia improves the titration of anesthetics in adults. The data from this study suggest that the same equipment and method of electroencephalogram analysis may be applied to infants and children.
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Anesthesia and analgesia · Apr 2000
Prophylactic percutaneous sealing of lumbar postdural puncture hole with fibrin glue to prevent cerebrospinal fluid leakage in swine.
We explored the effect of fibrin glue injection at the site of dural puncture on cerebrospinal fluid (CSF) leakage in a swine model. Pigs were subjected to a lumbar dural CSF puncture in the sitting position with a 17-gauge Tuohy needle. Fibrin glue 1.4 mL was injected through the same needle into the epidural space. Evans blue dye was infused through the cisterna magna 15 min later, and the appearance of dyed CSF through the skin puncture and along the needle trajectory to the dura was inspected and categorized. In seven of eight animals, the CSF leak was sealed with fibrin glue. Control animals were injected with 1.4 mL saline. A sham operation group of animals underwent cisternal dye infusion without a lumbar puncture. CSF pressure at the cisterna magna was recorded throughout the procedure. No significant differences in the leakage indicators were found between the fibrin glue-injected and sham-operated group, whereas both groups showed significant differences with respect to the control group. The fibrin glue seal was effective against CSF pressures of 24.5 [17-31] cm H(2)O. We conclude that percutaneously injected fibrin glue is effective in stopping CSF leaks after dural puncture in this animal model. ⋯ In this swine study, we repaired a cerebrospinal fluid leak after a dural puncture by percutaneously injecting tissue adhesive. The technique of percutaneous injection of fibrin glue seems promising for the prophylaxis of headache associated with cerebrospinal fluid leakage, and may be an alternative to an epidural blood patch.