Home About us Contact
|
Home About us Contact | ||
|
|
||
Anesthetic Protocols (anesthetic + protocol)
Selected AbstractsDifferent behavioral effects of neurotoxic dorsal hippocampal lesions placed under either isoflurane or propofol anesthesiaHIPPOCAMPUS, Issue 3 2008Mark G. Baxter Abstract Anesthetic protocols for behavioral neuroscience experiments are evolving as new anesthetics are developed and surgical procedures are refined to improve animal welfare. We tested whether neurotoxic dorsal hippocampal lesions produced under two different anesthetic protocols would have different behavioral and/or histo-pathological effects. Rats were anesthetized with either propofol, an intravenous anesthetic, or isoflurane, a gaseous anesthetic, and multiple injections of an excitotoxin (N -methyl- D -aspartate) were stereotaxically placed in the dorsal hippocampus bilaterally. Intraoperative physiological parameters were similar in the two surgical groups, as were the volumes of the lesions, although the profile of postoperative impairment in a spatial learning task differed between the lesion groups depending on the anesthetic regimen used. These results show that the choice of anesthetic protocol is a critical variable in designing behavioral neuroscience experiments using neurosurgical procedures. This factor should be considered carefully in experimental design and in cross-study comparisons of lesion effects on behavior. © 2007 Wiley-Liss, Inc. [source] Introduction of an OPCAB Program Aimed at Total Arterial Grafting in a Multidisciplinary Setting: Feasible and Safe?JOURNAL OF CARDIAC SURGERY, Issue 2 2007Xavier M. Mueller M.D. Uniform surgical and anesthetic protocols were established and applied throughout the study period. Methods: From March 2003,when the first OPCAB procedure of the program was performed,to July 2004, the data related to all the coronary artery bypass grafting procedures (N = 408) were prospectively recorded. The program was divided into two stages: the purpose of the first stage was to perform OPCAB in more than 90% of the patients, and that of the second stage was to proceed toward total arterial revascularization. The patients were grouped into four periods (102 patients for each period). Comparisons were performed with analysis of variance test and chi-square test where appropriate. Results: For periods 1 to 4, the number of OPCAB procedures was 65/102 (64%), 82/102 (80%), 97/102 (95%), and 99/102 (97%), respectively (p < 0.001). The number of conversions did not vary significantly throughout the study (overall: 7/408, 1.7%), neither did the number of bypass/patient (overall: 3.05 ± 0.86). The number of arterial graft/patient was 1.03 ± 0.64, 1.01 ± 0.4, 1.29 ± 0.64, and 2.56 ± 1, respectively (p < 0.001). During the last period, 81% (253/312) of the grafts were arterial. Overall mortality was 4.6% (19/408). For the OPCAB group, mortality was 2.9% (10/343) and perioperative myocardial infarction rate was 1.5% (5/343) with no statistically significant difference between the periods. Conclusions: With predefined standardized and coordinated protocols, an OPCAB program aimed at total arterial revascularization can be implemented rapidly and safely in a multidisciplinary setting. [source] Effects of remifentanil/propofol in comparison with isoflurane on dynamic cerebrovascular autoregulation in humansACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 8 2001K. Engelhard Background: This study investigates the effects of remifentanil and propofol in comparison to isoflurane on dynamic cerebrovascular autoregulation in humans. Methods: In 16 awake patients dynamic cerebrovascular autoregulation was measured using transcranial Doppler sonography (TCD). Thereafter patients were intubated, ventilated with O2/air (FiO2=0.33) and randomly assigned to one of the following anesthetic protocols: group 1 (n=8): 0.5 ,g · kg,1 · min,1 remifentanil combined with a propofol-target plasma concentration of 1.5 ,g · ml,1; group 2 (n=8): 1.8 % isoflurane (1.5 MAC). Following 20 min of equilibration the autoregulatory challenge was repeated. Arterial blood gases and body temperature were maintained constant over time. Statistics: Mann-Whitney U-test and Wilcoxon signed-rank test. Results: Dynamic autoregulation was intact in all patients prior to induction of anesthesia expressed by an autoregulatory index (ARI) of 5.4±1.21 (mean±SD, group 1) and 5.9±0.98 (mean±SD, group 2). With remifentanil/propofol anesthesia dynamic autoregulation was similar to the awake state (group 1: ARI=4.9±0.88). In contrast, autoregulatory response was delayed with 1.5 MAC isoflurane (group 2, ARI=2.1±0.92) (P<0.05). Conclusion: These data show that dynamic cerebrovascular autoregulation is maintained with remifentanil-based total intravenous anesthesia. This is consistent with the view that narcotics (and hypnotics) do not alter the physiologic cerebrovascular responses to changes in MAP. In contrast, 1.5 MAC isoflurane delays cerebrovascular autoregulation compared to the awake state. [source] | ||||||||||