Anesthesia and analgesia
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Anesthesia and analgesia · Jun 2004
The effect of propofol on cytotoxicity and apoptosis of lipopolysaccharide-treated mononuclear cells and lymphocytes.
IV anesthetics may inhibit proper immune responses and further compromise an already depressed defense system. To assess the possible role of propofol on human immune function in sepsis, we studied cytotoxicity, and apoptosis of mononuclear cells (MNCs). Peripheral blood MNCs were preincubated in 1 microg/mL of lipopolysaccharide (LPS) and then reincubated in different concentrations of propofol (1 microg/mL, 5 microg/mL, 10 microg/mL, or 50 microg/mL). To determine cytotoxicity, lactate dehydrogenase release was assayed by mixing MNCs (4 x 10(5)/100 microL) with K-562 tumor cells as target cells (1 x 10(4)/100 microL)(E: T ratio of 40:1). Apoptosis was determined by measuring the annexin positive cells using flow cytometry. Cytotoxicity and apoptosis of LPS-treated MNCs were unchanged by clinically acceptable concentrations of propofol (1 microg/mL, 5 microg/mL, and 10 microg/mL). However, significant differences were observed in cytotoxicity (P = 0.004) and apoptosis (P = 0.002) with propofol 50 microg/mL. By gating MNCs, we found that lymphocyte apoptosis was significantly increased at 50 microg/mL of propofol, but monocytes were unaffected (P = 0.02). In terms of cytotoxicity and apoptosis, propofol allowed MNCs to retain their cytotoxicity in septic conditions by protecting immune cells from apoptosis. ⋯ Propofol at acceptable therapeutic concentrations, and under experimentally contrived septic conditions, did not affect the cytotoxic activity of mononuclear cells or the apoptosis level of mononuclear cells, lymphocytes, and monocytes from peripheral blood.
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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.
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Anesthesia and analgesia · Jun 2004
Intraosseous vascular access in the treatment of chemical warfare casualties assessed by advanced simulation: proposed alteration of treatment protocol.
Current treatment protocols for chemical warfare casualties assume no IV access during the early treatment stages. Time constraints in mass casualty scenarios, impaired manual dexterity of medical personnel wearing protective gear, and victims' complex clinical presentations render standard IV access techniques impractical. A newly developed spring-driven, trigger-operated intraosseous infusion device may offer an effective solution. Sophisticated simulators were developed and used to mimic scenarios of chemical warfare casualties for assessing the feasibility of intraosseous infusion delivery. We evaluated the clinical performance of medical teams in full protective gear. The success rate in intraosseous insertion, time to completion of treatment goals, and outcome were measured in a simulated setting. Medical teams from major hospitals in Israel, designated for emergency response in a real chemical warfare mass casualty scenario, were trained in a simulated setting. All 94 participating physicians were supplied with conventional treatment modalities: only the 64 study group physicians received intraosseous devices. The simulated survival rate was 73.4% for the study group and 3.3% for the controls (P < 0.001). Treatment goals were achieved within 3.5 min (range, 1-9 min) in the study group and within >10 min for controls (P < 0.001), and the complication rate for intraosseous use was 13.8%. Personnel satisfaction with the intraosseous device was unanimous and high. New-generation intraosseous infusions have great potential value in the early treatment stages of chemical warfare casualties. ⋯ In a chemical warfare mass casualty scenario, the protective gear worn by medical personnel, the time constraints, and the casualties' medical condition impose limitations on the establishment of IV access during early treatment of the victims. A spring-driven, trigger-operated intraosseous infusion delivery system may offer an effective solution.
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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.