Comparison of the effects of desflurane and sevoflurane on the expression of platelet surface glycoproteins in unstimulated and adenosine diphosphate-induced platelets in vitro.

STUDY OBJECTIVE: To compare the effects of one minimum alveolar concentration (MAC) desflurane and sevoflurane on the expression of CD42b (glycoprotein [GP] Ib), CD41 (GPIIb), CD61 (GPIIIa), CD62P (P-selectin), and CD63 in both unstimulated and adenosine diphosphate (ADP)-stimulated platelets in vitro. SETTING: University laboratory. SUBJECTS: 15 healthy volunteers. INTERVENTIONS: Platelet-rich plasma was obtained and divided into three groups: platelet-rich plasma exposed to air (group 1); air plus one MAC desflurane (6% vol; group 2), and air plus one MAC sevoflurane (2% vol; group 3), for 40 minutes. Percentage of antigen-positive cells (%(+)) mean channel fluorescence (MCF(Sigma)), and index of platelet activation for positive platelets (IPA(+)) as expression markers for GPIb, GPIIb, GPIIIa, P-selectin, and CD63, were measured. MEASUREMENTS AND MAIN RESULTS: In unstimulated platelets, expression markers for GPIIb and GPIIIa were significantly lower in groups 2 and 3 than group 1 (P < 0.001). P-selectin expression markers were significantly higher in group 2 than in group 1 or group 3 (P < 0.016). CD63 expression markers were significantly lower in group 3 than group 1 (P < 0.016). In ADP-stimulated platelets, expression markers for all glycoproteins were significantly higher in all groups. CONCLUSION: Neither one MAC desflurane nor sevoflurane showed any significant change in ADP-stimulated platelets compared with the control group.

A comparison of the sedative, hemodynamic, and respiratory effects of dexmedetomidine and propofol in children undergoing magnetic resonance imaging.

We compared the sedative, hemodynamic, and respiratory effects of dexmedetomidine and propofol in children undergoing magnetic resonance imaging procedures. Sixty children were randomly distributed into two groups: The dexmedetomidine (D) group received 1 microg/kg initial dose followed by continuous infusion of 0.5 microg.kg(-1).h(-1) and a propofol group (P) received 3 mg/kg initial dose followed by a continuous infusion of 100 microg.kg(-1).min(-1). Inadequate sedation was defined as difficulty in completing the procedure because of the child's movement during magnetic resonance imaging. Mean arterial pressure (MAP), heart rate, peripheral oxygen saturation, and respiratory rate (RR) were recorded during the study. The onset of sedation, recovery, and discharge time were significantly shorter in group P than in group D. MAP, heart rate, and RR decreased during sedation from the baseline values in both groups. MAP and RR were significantly lower in group P than in group D during sedation. Desaturation was observed in four children of group P. Dexmedetomidine and propofol provided adequate sedation in most of the children. We conclude that although propofol provided faster anesthetic induction and recovery times, it caused hypotension and desaturation. Thus, dexmedetomidine could be an alternative reliable sedative drug to propofol in selected patients.