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21.
Kassiani Theodoraki Panagiota Rellia Apostolos Thanopoulos Loukas Tsourelis Dimitrios Zarkalis Petros Sfyrakis Theophani Antoniou 《Journal canadien d'anesthésie》2002,49(9):963-967
PURPOSE: Severe pulmonary hypertension (PH) is a major cause of right ventricular (RV) dysfunction. Various iv vasodilator modalities have been used with limited results because of lack of pulmonary selectivity. The aim of the present controlled study was to evaluate the efficacy of inhaled iloprost, a synthetic prostacyclin analogue, in patients with elevated pulmonary vascular resistance (PVR) immediately after separation from cardiopulmonary bypass (CPB). METHODS: Twelve patients with persistent PH after discontinuation of CPB were included in the study. In all patients standard hemodynamic monitoring was used. Inhaled iloprost was administered via nebulized aerosol at a cumulative dose of 0.2 micro g*kg(-1) for a total duration of 20 min. Complete sets of hemodynamic measurements were performed before inhalation (baseline), during and after cessation of the inhalation period. Echocardiographic monitoring of RV function was also used. RESULTS: Inhaled iloprost induced a reduction in the transpulmonary gradient at the end of the inhalation period in comparison to baseline (9.33 +/- 3.83 mmHg vs 17.09 +/- 6.41 mmHg, P < 0.05). The mean pulmonary artery pressure to systemic artery pressure ratio decreased over this period (0.28 +/- 0.08 vs 0.45 +/- 0.17, P < 0.05). A statistically significant decrease of the PVR to systemic vascular resistance ratio was also observed (0.15 +/- 0.05 vs 0.21 +/- 0.05, P < 0.05). Improved indices of RV function were observed in echocardiographic monitoring. CONCLUSION: Inhaled iloprost appears to be a selective pulmonary vasodilator and may be effective in the initial treatment of PH and the improvement of RV performance in the perioperative setting. 相似文献
22.
《Antibiotiques》2007,9(1):47-53
The purpose of the present work was to evaluate the intra-tonsillar concentrations of roxithromycin (ROX), clarithromycin (CLR) and 14-OH-CLR at steady state in children, and then to compare them with their respective MICs against group A Streptococci. It was a monocenter, pharmacokinetic study in children hospitalized for a tonsillectomy and receiving in a randomized manner either roxithromycin 3 mg/kg bid, or clarithromycin 7.5 mg/kg bid, for three days. The last dose in both groups was randomly administered either 2, or 4 or 12 hours before the bilateral tonsillectomy. The tissue sample was concomitent to a blood sample. Blood and tissue concentrations of macrolides were performed by HPLC.ResultsMean blood (mg/l) and tissue (mg/kg) concentrations are as follows (mean+/-SD) : serum concentrations (mg/L) (mg/kg) (mean, SD), as decreasing from 2d to 12th hour, are respectively 7.51±4.28 to 2.34±0.67 for ROX, of 1.83±1.15 to 0.62±0.53 for CLR and of 0.81±0.35 à 0.51±0.16 for 14-OH-CLR. For tonsils decreasing concentrations at the same sampling times were 0.81±0.48 to 0.29±0.14 for ROX, of 1.81±0.48 to 0.78±0.14 for CLR, of 0.78±0.49 to 0.51±0.14 for 14-OH-CLR. The areas under the serum concentrations curves (AUC) for ROX and CLR+ 14-OH-CLR (CLRtot) were respectively 53.8 and 22.5 μg.h.ml-1. The corresponding values for the tonsils were respectively 7.0 and 26.15. The rate of penetration as determined by the AUC serum/AUC tissue ratios are 13% and 116.2% for ROX and CLR tot respectively.As a consequence in terms of antibacterial activity, and as far as CLR and 14-OH-CLR MICs are regularly four times lower than those of ROX, and considering that intra-tonsillar concentrations of CLRtot vs ROX were 3.6 (2 h), 2.3 (4 h) and 4.4 (12 h) times higher than those of ROX, the resulting inhibitory quotients are up to 13-18 times higher for CLR, without taking into account the synergy that is likely to occur between CLR and 14-OH-CLR.ConclusionThe better antibacterial activity and tonsillar pharmacokinetics of CLR and its active metabolite 14-OH-CLR confer to these components pharmacodynamic properties which are more in adequation with the pre-requisites correlating with a suitable bacterio-clinical efficacy when compared with ROX. 相似文献
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A. PESONEN R. SUOJARANTA-YLINEN E. HAMMARÉN P. TARKKILA T. SEPPÄLÄ P. H. ROSENBERG 《Acta anaesthesiologica Scandinavica》2009,53(1):101-108
Background: In elderly patients, opioids may cause prominent postoperative sedation and respiratory depression. We evaluated the influence of age on the effects of opioids and plasma concentrations of fentanyl and oxycodone in cardiac surgery patients.
Methods: Thirty (≥75 years, gender M9/F21) and 20 (≤60 years, gender M20/F0) patients scheduled to undergo cardiac surgery. A standard anesthesia with fentanyl as an opioid was used. Fentanyl plasma concentrations were measured at the end of surgery and 2 h later. After tracheal extubation, when the pain intensity was at least moderate, blood samples for fentanyl and oxycodone plasma concentration measurements were taken. Thereafter, oxycodone hydrochloride 0.05 mg/kg i.v. was administered. After 15 and 45 min, pain intensity, sedation and oxycodone plasma concentration were determined. This test protocol was repeated twice.
Results: The elderly had a higher plasma concentration of fentanyl at the end of surgery than younger patients (5.7±2.2 vs. 3.8±1.2 ng/ml, P =0.001). The plasma concentrations of oxycodone were comparable between the groups. The interval between the second and the third oxycodone dose was longer in the elderly patients ( P =0.036). Pain intensity on the verbal rating scale was lower at the 45-min assessment point after all three oxycodone test doses ( P =0.008) and sedation scores were significantly higher after the third dose in the elderly patients ( P =0.035).
Conclusions: In elderly patients, the plasma concentration of fentanyl was higher but plasma levels of oxycodone were at a similar level compared with middle-aged patients. However, the elderly patients had less pain and were more sedated after doses of oxycodone. 相似文献
Methods: Thirty (≥75 years, gender M9/F21) and 20 (≤60 years, gender M20/F0) patients scheduled to undergo cardiac surgery. A standard anesthesia with fentanyl as an opioid was used. Fentanyl plasma concentrations were measured at the end of surgery and 2 h later. After tracheal extubation, when the pain intensity was at least moderate, blood samples for fentanyl and oxycodone plasma concentration measurements were taken. Thereafter, oxycodone hydrochloride 0.05 mg/kg i.v. was administered. After 15 and 45 min, pain intensity, sedation and oxycodone plasma concentration were determined. This test protocol was repeated twice.
Results: The elderly had a higher plasma concentration of fentanyl at the end of surgery than younger patients (5.7±2.2 vs. 3.8±1.2 ng/ml, P =0.001). The plasma concentrations of oxycodone were comparable between the groups. The interval between the second and the third oxycodone dose was longer in the elderly patients ( P =0.036). Pain intensity on the verbal rating scale was lower at the 45-min assessment point after all three oxycodone test doses ( P =0.008) and sedation scores were significantly higher after the third dose in the elderly patients ( P =0.035).
Conclusions: In elderly patients, the plasma concentration of fentanyl was higher but plasma levels of oxycodone were at a similar level compared with middle-aged patients. However, the elderly patients had less pain and were more sedated after doses of oxycodone. 相似文献
25.
目的:观察喉罩全麻下行颈动脉狭窄的造影诊断及介入治疗术的临床效果。方法:择期DSA下颈动脉狭窄患者23例,年龄42-78岁,无明显肺部疾患及喉罩禁忌症患者,异丙酚(Pmpofol)泵入静脉全麻下插入喉罩完成手术,观察其不同时段的BP(MAP)、SpO2、HR、ECG(ST-Ⅱ)。结果:各时段的BP(MAP)、Sp02、HR、ECG(ST-Ⅱ)比较无显著性差异。结论:喉罩全麻在行颈动脉狭窄的造影诊断及介入治疗术的临床效果是肯定的。喉罩全麻颈动脉狭窄造影介入治疗 相似文献
26.
Effects of halothane on spinal dorsal horn WDR(wide dynamic range) neuronal activity in cats 总被引:1,自引:0,他引:1
H Nagasaka S Nakamura T Genda T Miyazaki K Aikawa N Matsumoto I Matsumoto T Hori I Sato 《Masui. The Japanese journal of anesthesiology》1991,40(7):1096-1101
The effects of halothane (0.2%, 0.5%, and 1.0%) on the spinal dorsal horn wide dynamic range (WDR) neuronal activity was studied in either spinal cord intact or spinal transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind foot pads of intact or decerebrate, spinal cord transected (L 1-2) cats. When 10 micrograms of bradykinin was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cat, all of 7 WDR neurons gave excitatory responses which were not depressed by 0.2% and 0.5% halothane but were depressed significantly by 1.0%. On the other hand, when the injection of 10 micrograms of bradykinin into the femoral artery ipsilateral to the recording site was used in the intact cat, 7 of 14 WDR neurons (50%) gave excitatory responses, which were not depressed by 0.2% halothane but were significantly depressed by 0.5% and 1.0% halothane, and 7 of 14 WDR neurons (50%) gave inhibitory responses, which were significantly depressed by 0.2%, 0.5%, and 1.0% halothane. We have found that halothane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by bradykinin injection. 相似文献
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Ryo Wakita Yuka Ohno Saori Yamazaki Hikaru Kohase Masahiro Umino 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,102(6):e28-e32
Two cases of vasovagal syncope (VVS) during venous access are reported. Both patients had a history of fainting episodes and experienced bradycardia with asystole, hypotension, and fainting. Pain and phobic stress during venous access triggered an increase in parasympathetic tone, resulting in bradycardia with asystole and hypotension in both cases. Hypotension and bradycardia likely caused cerebral hypoperfusion, leading to fainting. The intense parasympathetic tone triggered by somatic or emotional stress was likely responsible for directly depressing the sinus node, leading to asystole and bradycardia. Bradycardia with asystole progressing to syncope is a potentially fatal dysrhythmia in patients with cardiovascular disease or older patients with decreased cardiac function. Appropriate treatment for VVS includes the administration of intravenous fluids, vagolytics, ephedrine, and the rapid use of the Trendelenburg position. Intravenous fluids and atropine were used to treat the present patients. 相似文献