Anesthesia and analgesia
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Anesthesia and analgesia · Dec 2004
Case ReportsVenous air embolism during transurethral resection of the prostate.
Venous air embolism during transurethral surgery is a rare event. There have been case reports in the anesthesia and urology literature of fatal air embolism during transurethral prostate resection and transurethral incision of the bladder neck. We present a case of nonfatal venous air embolism during transurethral prostate resection in which incorrect assembly of the bladder irrigation-resectoscope-drain system led to a rapid entrainment of air into the open venous channels of the prostate bed.
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Anesthesia and analgesia · Dec 2004
Measuring depth of sedation with auditory evoked potentials during controlled infusion of propofol and remifentanil in healthy volunteers.
Avoiding excessively deep levels of sedation is a major problem in intensive care patients. We studied whether clinically relevant levels of sedation can be objectively assessed using long latency auditory evoked potentials. We measured the auditory evoked potentials at 100 ms after the stimulus (N100) in 10 healthy volunteers during stepwise increasing, clinically relevant levels of sedation (Ramsay score [RS] 2-4). ⋯ During both propofol-induced and propofol/remifentanil-induced sedation, the N100 amplitude decreased similarly without an effect on the latencies as the level of sedation increased from Ramsay score 2 to Ramsay score 4 (P < 0.01). At the same clinical level of sedation, propofol plasma concentrations were larger when sedation was achieved by propofol alone (propofol versus propofol/remifentanil, RS 3: 2.12 mug/mL +/- 0.51 versus 1.32 +/- 0.43, P < 0.01; RS 4: 3.37 +/- 0.47 versus 1.86 +/- 0.34, P < 0.01). Our results suggest that long latency auditory evoked potentials provide an objective electrophysiological analog to the clinical assessment of sedation independent of the sedation regime used.
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Anesthesia and analgesia · Dec 2004
The development and validation of a risk score to predict the probability of postoperative vomiting in pediatric patients.
Risk scores to predict the occurrence of postoperative vomiting (PV) or nausea and vomiting that were developed for adult patients do not fit for children, because several risk factors are difficult to assess or are usually not applicable in pediatric patients (e.g., smoking status). Thus, in the present study, we sought to develop and to validate a simple score to predict PV in children (POVOC-score). Development and validation of the new score was based on data from 4 independent institutions of 1257 children (aged 0-14 yr) undergoing various types of surgery under general anesthesia without antiemetic prophylaxis. ⋯ The incidence of PV was 9%, 10%, 30%, 55%, and 70% for 0, 1, 2, 3, and 4 risk factors observed. Using these incidences as cut-off values in the validation dataset, the area under the receiver operating characteristic curve was 0.72 (95% confidence interval: 0.68-0.77). Our data suggest that PV can be predicted with an acceptable accuracy using a four-item simplified risk score.
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Anesthesia and analgesia · Dec 2004
Clinical TrialThe intravenous ketamine test: a predictive response tool for oral dextromethorphan treatment in neuropathic pain.
IV infusion tests performed to predict subsequent response to oral analgesics are an increasingly popular method used to enhance medical care and conserve resources. Because no infusion test is completely accurate, the potential benefits of these tests must be weighed against the frustration and waste in resources encountered with false-positive results, and the failure to use a potentially beneficial treatment with false-negative results. In recent years, drugs that act antagonistically at N-methyl-d-aspartate receptors have been shown to be valuable adjuncts in the treatment of pain. ⋯ However, when >/=67% relief with ketamine was used as an outcome measure (as determined by a receiver operating characteristic curve), the positive predictive value was 90%, the negative predictive value 80%, and the observed agreement increased to 84%. Based on these results, we conclude that an IV ketamine test may be useful in predicting response to oral DX. More research is needed to determine the ideal candidates for such a test, and the optimal dose and cutoff value for the response to ketamine.
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Anesthesia and analgesia · Dec 2004
The effect of dilution on plasma coagulation kinetics determined by thrombelastography is dependent on antithrombin activity and mode of activation.
Hemodilution-associated hypercoagulability has been the focus of several investigations because significant morbidity and mortality have been associated with perioperative thrombophilia. Because most investigations implicate imbalances in procoagulant/anticoagulant activity as the etiology of hemodilution-associated hypercoagulability, we determined the effects of dilution on coagulation kinetics and clot strength with thrombelastography (TEG(R)). Control plasma (+/-celite activation) and antithrombin (AT)-deficient (<10% activity) plasma were diluted 0%, 10%, 20%, and 30% with saline. ⋯ Celite activation eliminated dilution-associated changes in R values in control plasma but resulted in linear decreases (R(2) = 0.88-0.96, P < 0.0001) in alpha, A, and G in response to dilution. Thus, our data indirectly support the concept that decreases in AT activity cause dilution-mediated hypercoagulability in plasma. Finally, celite activation permits quantification of dilution with TEG.