Anesthesiology
-
Methadone clearance is highly variable, and drug interactions are problematic. Both have been attributed to CYP3A, but actual mechanisms are unknown. Drug interactions can provide such mechanistic information. Ritonavir/indinavir, one of the earliest protease inhibitor combinations, may inhibit CYP3A. We assessed ritonavir/indinavir effects on methadone pharmacokinetics and pharmacodynamics, intestinal and hepatic CYP3A activity, and intestinal transporters (P-glycoprotein) activity. CYP3A and transporters were assessed with alfentanil and fexofenadine, respectively. ⋯ Inhibition of both hepatic and intestinal CYP3A activity is responsible for ritonavir/indinavir drug interactions. Methadone disposition was unchanged, despite profound inhibition of CYP3A activity, suggesting little or no role for CYP3A in clinical methadone metabolism and clearance. Methadone bioavailability was unchanged, despite inhibition of gastrointestinal P-glycoprotein activity, suggesting that this transporter does not limit methadone intestinal absorption.
-
Comparative Study
Anesthesiology trainees face ethical, practical, and relational challenges in obtaining informed consent.
Categorizing difficulties anesthesiologists have in obtaining informed consent may influence education, performance, and research. This study investigated the trainees' perspectives and educational needs through a qualitative analysis of narratives. ⋯ The ethical, practical, and relational challenges in obtaining informed consent colored trainees' views of patient care and affected their interactions with patients. Using participant narratives personalizes education and motivates participants. The richness of narratives may help anesthesiologists to appreciate the qualitative aspects of informed consent.
-
Comparative Study
Intraoperative fraction of inspired oxygen is a modifiable risk factor for surgical site infection after spinal surgery.
Surgical site infections (SSI) after spinal surgery increase morbidity, mortality, length of hospital stay, and costs. Most previously identified risk factors for these infections, such as severity of illness and procedure duration, are not amenable to intervention. This study sought to identify modifiable risk factors associated with SSI after spinal surgery. ⋯ In addition to previously reported risk factors, this study identified intraoperative administered fraction of inspired oxygen of less than 50% as an independent, modifiable risk factor for SSI after spinal surgery. Intraoperative administration of at least 50% fraction of inspired oxygen should be tested prospectively as an intervention to prevent SSI after spinal surgery.
-
Comparative Study
Further proof that the spinal cord, and not the brain, mediates the immobility produced by inhaled anesthetics.
Previous investigations indicate that the spinal cord, perhaps with a minor cerebral contribution, mediates the capacity of inhaled anesthetics to produce immobility in the face of noxious stimulation. The implications of these investigations may be limited by the trauma associated with their experimental methods (e.g., cardiopulmonary bypass or transection of the spinal cord). The present study avoided such trauma. ⋯ In this novel and minimally traumatic model, the anesthetic partial pressure delivered to the spinal cord governed the suppression of movement in response to noxious stimulation. The results indicate that the spinal cord is the primary mediator of immobility and that the brain plays little or no role.
-
Comparative Study
Neonatal exposure to sevoflurane induces abnormal social behaviors and deficits in fear conditioning in mice.
Neonatal exposure to anesthetics that block N-methyl-D-aspartate receptors and/or hyperactivate gamma-aminobutyric acid type A receptor has been shown to cause neuronal degeneration in the developing brain, leading to functional deficits later in adulthood. The authors investigated whether exposure of neonatal mice to inhaled sevoflurane causes deficits in social behavior as well as learning disabilities. ⋯ This study shows that exposure of neonatal mice to inhaled sevoflurane could cause not only learning deficits but also abnormal social behaviors resembling autism spectrum disorder.