Tolerance to pain and sensitivity to rising concentrations of inhaled carbon dioxide were measured before and after administration of methadone, 5 mg, or hydromorphone, 0.5 mg, by the intravenous route and by epidural injection in the lumbar or upper thoracic region in 5 subjects. Tolerance to periosteal pressure, cutaneous electrical stimulation and the cold pressor response to ice-water immersion were measured in both upper and lower limbs. Tolerance to all three pain modalities was greater in the epidural "blocked" limbs than in the "unblocked" limbs or after intravenous administration, and this difference was sustained after a second injection of narcotic. Sensitivity to carbon dioxide was less depressed by epidural narcotic than by intravenous administration; however, after a second dose of narcotic, depression of CO2 sensitivity by epidural injection was comparable to that produced by intravenous injection. These observations support the hypothesis that epidural narcotics have a segmental action as well as a systemic effect, and that both actions are dose-dependent.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0304-3959(80)90003-2 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Experimental study on the effect of CO2 injection on the permeability characteristics of reservoir sandstone.
PLoS One
January 2025
School of Mechanics and Engineering, Liaoning Technical University, Fuxin, Liaoning, China.
Using the Ordos Basin dry sandstone and sandstone saturated with different saline concentrations as research subjects, a self-developed constant temperature and pressure CO2 injection simulation device was employed to conduct permeability tests on sandstone under varying effective stresses and CO2 injection pressures. The test results indicated that during the CO2 injection process, the permeability of dry sandstone was two orders of magnitude higher than that of sandstones saturated with different saline concentrations. When the effective stress increases from 10 MPa to 28 MPa, the fissure compressibility of reservoir sandstone is influenced by the saturation of different saline concentrations, with the compressibility coefficients for 0%, 15%, and 30% saline-saturated sandstone being 0.
View Article and Find Full Text PDFEffects of Variable Ventilation on Gas Exchange in an Experimental Model of Capnoperitoneum: A Randomized Crossover Study.
Anesth Analg
January 2025
From the Unit for Anaesthesiological Investigations, Department of Anaesthesiology, Pharmacology, Intensive Care and Emergency Medicine, University of Geneva, Geneva, Switzerland.
Background: The rapid advancement of minimally invasive surgical techniques has made laparoscopy a preferred alternative because it reduces postoperative complications. However, inflating the peritoneum with CO2 causes a cranial shift of the diaphragm decreasing lung volume and impairing gas exchange. Additionally, CO2 absorption increases blood CO2 levels, further complicating mechanical ventilation when the lung function is already compromised.
View Article and Find Full Text PDFHinged Carboxylate in the Artificial Distal Pocket of an Iron Porphyrin Enhances CO Electroreduction at Low Overpotential.
Adv Sci (Weinh)
January 2025
Université Paris-Saclay, CNRS, Institut de Chimie Moléculaire et des Matériaux d'Orsay, Orsay, 91400, France.
To efficiently capture, activate, and transform small molecules, metalloenzymes have evolved to integrate a well-organized pocket around the active metal center. Within this cavity, second coordination sphere functionalities are precisely positioned to optimize the rate, selectivity, and energy cost of catalytic reactions. Inspired by this strategy, an artificial distal pocket defined by a preorganized 3D strap is introduced on an iron-porphyrin catalyst (sc-Fe) for the CO-to-CO electrocatalytic reduction.
View Article and Find Full Text PDFCerebral tissue oxygen saturation and its potential relationship with neurodevelopmental delay in pediatric liver transplant recipients.
Front Pediatr
January 2025
Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China.
Objective: To discover the potential association between diminished intraoperative average SctO levels and postoperative neurodevelopmental delays among patients after pediatric living-donor liver transplantation.
Study Design: Patients undergoing living-donor liver transplantation were recruited for this trial. The neurodevelopment status of patients was assessed using the Ages Stages Questionnaires.
Physical cardiac rehabilitation effects on cardio-metabolic outcomes in the patients with hypertrophic cardiomyopathy: a systematic review.
Am J Cardiovasc Dis
December 2024
Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA.
Objectives: This systematic review aimed to review existing evidence to evaluate the effects of physical cardiac rehabilitation on cardio-pulmonary outcomes in the patients with hypertrophic cardiomyopathy (HCM).
Methods: We conducted a systematic search of the databases PubMed, Web of Science, Embase, Scopus, and Google Scholar. The initial search led to 1222 citations after removing duplicate results.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!