Anesthesia and analgesia
-
Anesthesia and analgesia · Jun 2004
Case ReportsPerioperative pain management of a complex orthopedic surgical procedure with double continuous nerve blocks in a burned child.
The use of catheters for continuous nerve blocks has been established in children, although in most series only one catheter was used. We report a case of a 3-yr-old child who underwent a toe-to-finger transfer managed with 2 regional catheters: axillary and sciatic. A pain score of 0 was noted during the entire study period. The total dose of bupivacaine was limited to an acceptable range, and the child recovered completely. This report adds to growing evidence in favor of the safety and efficacy of continuous peripheral nerve blocks in pediatric patients. ⋯ Double continuous nerve blocks allow optimal analgesia in burned children after complex orthopedic surgery without major adverse events. Plasma concentrations of bupivacaine remained small during the study period.
-
Anesthesia and analgesia · Jun 2004
Case ReportsSuperficial cervical plexus block for vocal cord surgery in an awake pediatric patient.
Medialization thyroplasty is a surgical procedure that decreases the incidence of dysphonia and dysphagia in patients who have vocal cord paralysis. We report a case of a pediatric patient who underwent this procedure with minimal sedation and bilateral superficial cervical plexus blockade. The use of a regional technique provided analgesia while allowing the patient to phonate at the request of the surgeon. ⋯ Medialization thyroplasty is a surgical procedure that decreases the incidence of dysphagia and dysphonia in patients with vocal cord paralysis. This procedure is best performed in a patient who maintains the ability to phonate. We report a case of medialization thyroplasty in a pediatric patient after bilateral superficial cervical plexus blocks with minimal sedation.
-
Anesthesia and analgesia · Jun 2004
Case ReportsIntracranial hypotension caused by cervical cerebrospinal fluid leak: treatment with epidural blood patch.
This report describes treatment with cervical epidural blood patch of low cerebrospinal fluid (CSF) pressure headache resulting from spontaneous CSF leak via a tear in a cervical dural cuff. The leak was diagnosed by a dynamic computed tomography (CT)-myelography study followed by gadolinium enhanced magnetic resonance imaging(MRI)-scan. The epidural needle was inserted with the aid of image intensifier and CT-scan to guide the needle to the precise site of the CSF leak. Blood mixed with gadolinium was injected, and subsequent MRI scanning provided the first description of spread of blood after cervical epidural blood patch. ⋯ Low cerebrospinal fluid (CSF) pressure may cause severe posturally-related headache. In the patient, a vertebral disc protrusion in the neck seems to have contributed to a CSF leak. An injection of blood into the epidural space at the precise site of the CSF leak was followed by complete and lasting resolution of the headache.
-
Anesthesia and analgesia · Jun 2004
Bispectral index during isoflurane anesthesia in pediatric patients.
Bispectral index (BIS) was developed to monitor anesthetic depth in adults, but has been investigated for use in children, using sevoflurane. We examined the concentration-response relationship between BIS and isoflurane. Thirty children undergoing cardiac catheterization received continuous intraoperative BIS monitoring and had BIS values recorded at 6 steady-state end-tidal isoflurane (Et(Iso)) concentrations between 1.5% and 0.5% and at first arousal. The mean (SD) values for BIS were as follows: 1.5%, 32.3 +/- 11.7; 1.3%, 34.7 +/- 12.5; 1.1%, 40.5 +/- 13.3; 0.9%, 48.0 +/- 13.7; 0.7%, 55.9 +/- 14.4; and 0.5%, 61.8 +/- 13.1. There was an inverse correlation between Et(Iso) and BIS (r = -0.634; P < 0.01). There were significant differences (P < 0.0001) in mean BIS values between adjacent Et(Iso) in all cases except 1.5% versus 1.3%. An inhibitory sigmoid E(max) model best described the BIS-isoflurane concentration relationship, with an 50% effective dose of 0.85% (95% confidence interval, 0.72%-0.98%). The mean value of BIS at first arousal was 78.5 +/- 12.3. The relationship between Et(Iso) and BIS is qualitatively and quantitatively similar to that described for isoflurane in adults and sevoflurane in children. These results add to the body of evidence that BIS is adequately calibrated for use in children older than 1 yr. ⋯ This observational study of children undergoing cardiac catheterization characterizes the concentration-response relationship between bispectral index and isoflurane and demonstrates that bispectral index seems adequately calibrated for monitoring the depth of isoflurane anesthesia in pediatric patients.
-
Anesthesia and analgesia · Jun 2004
Comparative StudyIsoflurane reduces glutamatergic transmission in neurons in the spinal cord superficial dorsal horn: evidence for a presynaptic site of an analgesic action.
The minimum alveolar concentration (MAC) of a volatile anesthetic defines anesthetic potency in terms of a suppressed motor response to a noxious stimulus. Therefore, the MAC of an anesthetic might in part reflect depression of motor neuron excitability. In the present study we evaluated the effect of isoflurane (ISO) on neurons in the substantia gelatinosa driven synaptically by putative nociceptive inputs in an in vitro spinal cord preparation of the rat. Whole-cell patch-clamp recordings were performed in neurons with their soma in the substantia gelatinosa of transverse rat spinal cord slices. We investigated the effect of ISO on excitatory postsynaptic currents (EPSC) evoked by dorsal root stimulation (eEPSC), spontaneous (sEPSC), and miniature (mEPSC) EPSC. ISO reversibly reduced the amplitude of eEPSC to 39% +/- 22% versus control. ISO decreased the frequency of sEPSC and mEPSC to 39% +/- 26% and 63% +/- 7%. Neither the amplitudes nor the kinetics of mEPSC and sEPSC were altered by ISO. We conclude that ISO depresses glutamatergic synaptic transmission of putative nociceptive primary-afferent inputs, presumably by reducing the release of the excitatory transmitter. This effect may contribute to an antinociceptive action of volatile anesthetics at the spinal cord level. ⋯ The present electrophysiological in vitro experiments provide evidence that the volatile anesthetic isoflurane reduces excitatory transmitter release at the first site of synaptic integration of nociceptive inputs, the spinal cord superficial dorsal horn. This effect may contribute to the anesthetic action of volatile anesthetics at the spinal cord level.