The effect of controlled hypotension induced by sodium nitroprusside alone or combined with propofol on human platelet aggregation
- VernacularTitle:硝普钠复合异丙酚控制性降压对血小板聚集功能的影响
- Author:
Ke MA
;
Cai FANG
;
Zhonglu CUI
- Publication Type:Journal Article
- Keywords:
Propofol;
Nitroprusside;
Platelet aggregation;
Hypotension, induced
- From:
Chinese Journal of Anesthesiology
1996;0(07):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective Hypotension can be induced by sodium nitroprusside(SNP) combined with propofol more easily and with less amount of each drug. But both SNP and propofol were reported to inhibit platelet aggregation. The purpose of present study was to investigate the effect of controlled hypotension induced by SNP alone or in combination with propofol on human platelet aggregation. Methods Fifty-six ASA Ⅰ -Ⅱ patients (30 male, 26 female), aged 20-54 (36.0 ? 11.2) years and weighing 42-79 (67.6?14.3)kg, undergoing elective neurosurgery were randomly assigned to one of four groups: A control group ( n = 14) ; B propofol group ( n = 14) ; C SNP group( n = 14) and D SNP + propofol group ( n = 14) . The patients were premedicated with luminal 0.lg and atropine 0.5 mg. Anesthesia was induced with midazolam 0.2 mg ?kg-1 , fentanyl 5 ?g?kg-1 and vecuronium 0.1 mg?kg-1 and maintained with isoflurane inhalation and intermittent boluses of fentanyl and vecuronium. In group A and B no hypotension was induced. In group C and D hypotension was induced by 0.01 % SNP infusion (0.5-5 ?g?kg-1?min-1 ) alone or combined with propofol infusion(2-3 mg?kg-1?h-1 ) . As soon as the dura was cut, hypotension was induced. MAP was reduced by 30 % and maintained at ( 67.80 ? 9.64 ) mm Hg on average. Radial artery was cannulated for continuous BP monitoring. In order to avoid the effect of colloid and homologous transfusion on platelet function, only Ringer' s lactate was infused during operation in the four groups. Blood samples were taken from peripheral vein before skin incision, 30min and 1h after hypotension was induced and 2h after surgery for determination of platelet aggregation, prothrombin time and plasma level of NO2 -/NO3- .Results Platelet aggregation was significantly inhibited in group C and D at 30 min and Ih after induction of hypotension as compared with the baseline (before operation) . There was significant difference in the inhibition of platelet aggregation among the four groups. The inhibition was greatest in group D. There was no significant change in prothrombin time after induction of hypotension in the four groups. Plasma level of NO2-/NO3 - increased significantly at 30 min and 1h after induction of hypotension in group C and D. Conclusions SNP combined with propofol has inhibitory effect on human platelet aggregation during controlled hypotension and increased in plasma NO2 -/NO3-level may be the mechanism.
