Anesthesia and analgesia
-
Anesthesia and analgesia · Oct 2002
Substance abuse among physicians: a survey of academic anesthesiology programs.
Efforts to reduce controlled-substance abuse by anesthesiologists have focused on education and tighter regulation of controlled substances. However, the efficacy of these approaches remains to be determined. Our hypotheses were that the reported incidence of controlled-substance abuse is unchanged from previous reports and that the control and accounting process involved in distribution of operating room drugs has tightened. We focused our survey on anesthesiology programs at American academic medical centers. Surveys were sent to the department chairs of the 133 US anesthesiology training programs accredited at the end of 1997. There was a response rate of 93%. The incidence of known drug abuse was 1.0% among faculty members and 1.6% among residents. Fentanyl was the controlled substance most often abused. The number of hours of formal education regarding drug abuse had increased in 47% of programs. Sixty-three percent of programs surveyed had tightened their methods for dispensing, disposing of, or accounting for controlled substances. The majority of programs (80%) compared the amount of controlled substances dispensed against individual provider usage, whereas only 8% used random urine testing. Sixty-one percent of departmental chairs indicated that they would approve of random urine screens of anesthesia providers. ⋯ This survey indicates that the frequency of controlled substance abuse among anesthesiologists has changed little in the past few years, despite an increase in the control and accounting procedures for controlled substances as well as increased mandatory education.
-
Anesthesia and analgesia · Oct 2002
A retrospective analysis of the costs and benefits related to alterations in cardiac surgery from routine intraoperative transesophageal echocardiography.
We sought to determine how frequently intraoperative transesophageal echocardiography (TEE) altered the planned surgical procedure and to assess the potential cost implications associated with these changes. A retrospective chart review was conducted at one university hospital. Cardiac surgical operative notes from July 1999 through June 2000 were reviewed. We interrogated all adult cardiac surgical records for patients scheduled for repair of coronary artery disease or valvular disease requiring the use of cardiopulmonary bypass. Cancellations based on TEE findings were included in the analysis. Of the 430 patient records reviewed, 24 procedures were ether canceled or changed on the basis of the intraoperative TEE examination (5.6%; 95% confidence interval, 3.6%-8.2%). Six of these cases involved valvular heart disease, and the remaining 18 involved the intraoperative diagnosis and repair of a patent foramen ovale. A cost-benefit analysis based on the 6 valvular diagnoses revealed a saving of $230 per patient. Assuming that unnecessary present or future operations may be avoided by altering the surgical plan on the basis of TEE findings, these preliminary data suggest that routine intraoperative TEE in cardiac surgery is beneficial and cost-effective. ⋯ A review of 430 adult cardiac surgical records indicates that routine transesophageal echocardiography during cardiac surgery, including coronary artery surgery, is beneficial and cost-effective.
-
Anesthesia and analgesia · Oct 2002
Comparative StudyThe actions of propofol on gamma-aminobutyric acid-A and glycine receptors in acutely dissociated spinal dorsal horn neurons of the rat.
The spinal cord plays an important role in modulating anesthetic-induced suppression of nociceptive transmission. To gain some insight into the anesthetic mechanisms of propofol at the spinal level, we investigated the direct action of propofol and its modulation on the gamma-aminobutyric acid-A receptor (GABA(A)R) and the glycine receptor (GlyR) in acutely dissociated rat spinal dorsal horn neurons by using whole-cell patch-clamp electrophysiology. Propofol induced Cl(-) currents (I(Cl)), which were sensitive to bicuculline and, to a lesser extent, to strychnine. The activation, desensitization, and deactivation of propofol-induced I(Cl) were slower than those of GABA- and glycine-induced I(Cl). In addition, this study revealed similar modulatory actions of propofol on GABA(A)R and GlyR. Propofol potentiated both GABA- and glycine-induced I(Cl) at small con-centrations and inhibited both GABA- and glycine-induced I(Cl) at large concentrations. The potentiation of propofol on I(Cl) was caused by slowing current desensitization and deactivation, whereas the inhibition actions might be involved in the cross-desensitization between GABA- and propofol-induced I(Cl) and the cross-inhibition between the GABA(A)R and GlyR. The results suggest that propofol facilitation of GABA(A)R and GlyR at the spinal level could contribute significantly to general anesthetic-induced analgesia and anesthesia. ⋯ The actions of propofol on the gamma-aminobutyric acid-A receptor (GABA(A)R) and the glycine receptor (GlyR) were investigated in acutely dissociated rat spinal dorsal horn neurons by using whole-cell patch-clamp electrophysiology. Propofol was found to potentiate the functions of GABA(A)R and GlyR at the spinal level, which might contribute to propofol-induced analgesia and anesthesia.
-
Anesthesia and analgesia · Oct 2002
Tumor necrosis factor-alpha reduces ketamine- and propofol-induced anesthesia time in rats.
Tumor necrosis factor-alpha (TNFalpha) is a crucial neuromodulator in the brain. TNFalpha is involved in many physiological events including pain response and sleep. However, the interactions between TNFalpha and anesthetics have not been elucidated yet. In the present study, we investigated the effects of four intracerebroventricular (ICV) doses (1, 10, and 100 pg, and 1 ng) and two intraperitoneal (IP) doses (10 and 100 ng) of TNFalpha on anesthesia time of ketamine (100 mg/kg IP) and propofol (80 mg/kg IP) in rats. All ICV doses of TNFalpha reduced anesthesia time of ketamine and propofol compared with the saline ICV group (ketamine control group, 45.4 +/- 6.5 min; propofol control group, 43.5 +/- 11.0 min). The maximum effect was obtained after the ICV injection of 10 pg of TNFalpha (76% and 54% of ketamine and propofol control groups, respectively). Anesthesia time of ketamine or propofol was also decreased by IP injection of TNFalpha in a dose-dependent manner. Injection of 100 ng of TNFalpha IP reduced anesthesia time of ketamine and propofol by 67% and 64% of each control group, respectively. These data show that TNFalpha can modulate the anesthesia time of IV anesthetics, suggesting that anesthetic requirements might be altered in the presence of cerebral or systemic inflammation. ⋯ Tumor necrosis factor alpha (TNFalpha) regulates many physiological events in the brain. We investigated the effects of TNFalpha on anesthesia time in rats. Both central and peripheral administration of TNFalpha decreased anesthesia time induced by ketamine and propofol.
-
Anesthesia and analgesia · Oct 2002
Hyperalgesia during opioid abstinence: mediation by glutamate and substance p.
Opioid-abstinence hyperalgesia (OAH) is a phenomenon characterized by thermal and mechanical hyperalgesia that occurs between intermittent doses of opioids or after the chronic administration of these drugs when administration is abruptly stopped. In these studies we attempted to determine whether the activation of spinal cord dorsal horn neurons was greater in mice with OAH than in control mice in response to the intrathecal administration of the primary neurotransmitters glutamate and substance P. After mice were treated with an established protocol consisting of the implantation of morphine pellets followed by removal after 6 days, the mice were hyperalgesic as assessed with the hotplate and Hargreaves thermal paw withdrawal assays. Mechanical allodynia was also demonstrated. The intrathecal injection of either glutamate (5-25 micro g) or substance P (0.02-0.1 nmol) caused greater pain behaviors in mice with OAH than in control mice. Likewise, it was observed that the dorsal horn regions of OAH mice had more Fos-positive nuclei after either glutamate or substance P administration than did control mice. We conclude that mice with OAH exhibit increased pain behaviors and have increased numbers of Fos-positive nuclei in response to intrathecal glutamate and substance P administration when compared with control mice. Thus, spinal sensitization to primary neurotransmitters may be responsible in part for the manifestation of OAH. ⋯ Opioids are a mainstay of treatment for many types of chronic pain. These studies provide evidence that the hyperalgesia induced by chronic opioid administration may be in part to spinal neuroplastic changes.