Effects Of Sufentanil Target-controlled Infusion On Thromboxane A₂ And Prostacyclin In Patients Undergoing Laparoscopic Cholecystectomy

Through laparoscopic operation has little operative trama, carbon dioxide pneumoperitoneum is a powerful stimulation for organism, stress reaction of patients increases and hemodynamics has changed significantly during operation, so there may be more relative postoperative complications. The dynamic balance of thromboxane A2 and prostacyclin is the major regulatory system of maintaining angiotasis and thrombocytic normal function, the ratio of them reflects vasomotion and microcirculation. Besides, it reflects degree of stress reaction. Sufentanil is the potentest analgesic with a very high receptor affinity and specificity, high lipid solubility, marked protein binding, and a shorter elimination half-life than fentanyl. Due to these dominances, sufentanil maintains stable hemodynamics. Target-controlled infusion(TCI) is the newest model of administration, opioids continuous infusion has less side-effect, more stable hemodynamics and faster conscious recovery, comparing with interruptable administration.Objective:This study is to investigate effects of sufentanil target-controlled infusion on thromboxane A2 and prostacyclin , comparing with fentanyl TCI in patients undergoing laparoscopic cholecystectomy.Methods:Twenty patients (ASAⅠ-Ⅱ)scheduled for selective laparoscopic cholecystectomy were randomized into two groups: sufentanil group (S group) and fentanyl group (F group). All patients had no history about cardiopulmanory disease , nerval and psychic disease, and didn't administer antiplatelet drugs and effecting coagulative drugs. Intramuscular injected atropine 0.5mg preoperation 30 minutes.After patiens entered, infused sodium lactate Ringer-Locke liquorand 6% MM HES, the rate of crystal and colloid was 2:1. Setted sufentanil and fentanyl effect-site concentration 0.4ng/ml,4ng/ml respectively during induction of anesthesia. Started sufentanil or fentanyl TCI, then intravenous injected midazolam 0.05-0.06mg/kg, propofol 1.5-2mg/kg, vecuronium bromide 0.1mg/kg,did tracheal intubation afer induction 3 minutes. Propofol continuous infused 5.0-6.0mg/kg.h during operation, and stopped infusion after surgery termination. Sufentanil or fentanyl TCI concentration keeped on during operation, and stopped infusion when washing abdominal cavity. Intra-abdominal pressure keeped on 12mmHg. Regulated tidal volume and breathing frequency to maintain partial pressure of carbon dioxide in endexpiratory gas(PETCO2) 35-40 mmHg. Recorded systolic pressure(SBP),diastolic pressure(DBP),heart rate(HR),saturation of blood oxygen(SpO2),partial pressure of carbon dioxide in endexpiratory gas(PETCO2) before anesthesia (T1), prepneumoperitoneum (T2), after pneumoperitomeum 20 min (T3), after removing pneumopetitomeum 10 minutes (T4), meanwhile adopted the venous blood to measure TXB2 and 6-Keto-PGF1αwith radio-immunity.Results:①after pneumoperitomeum 20 minutes, SBP,DBP were significantly increased in F group, comparing with before anesthesia(P<0.05), and with S group(P<0.05); Afer removing pneumoperitoneum 10 minutes, SBP was significantly increased in F group, comparing with before anesthesia(P<0.05).②Compared to before anesthesia, TXB2 was dramatically increased both groups after pneumoperitoneum 20 minutes(P<0.01), and after removing pneumoperitoneum 10 minutes(P<0.05); Compared with F group, TXB2 was significantly descreased in S group after pneumoperitoneum 20 minutes, afer removing pneumperitoneum 10 minutes(P<0.05).③Compared to beforeanesthesia, 6-Keto-PGF1αwas significantly heightened in S group at other times(P<0.05), and arrived at the peak after pneumoperitoneum 20 minutes. 6-Keto-PGF1αwas significantly increased in F group after pneumoperitoneum 20 minutes, comparing with before anesthesia(P<0.05). After removing pneumoperitoneum 10 minutes, 6-Keto-PGF1αwas significant higher in S group than in F group(P<0.05).④The rate of TXB2/6-Keto-PGF1αwas siginificantly descreased in S group before pneumperitoneum, comparing with before anesthesia(P<0.05); The rate of TXB2/6-Keto-PGF1αwas dramatically increased in F group after pneumoperitoneum 20 minutes and after removing pneumoperitoneum 10 minutes, comparing with before anesthesia(P<0.01). Compared to F group, the rate of TXB2/6-Keto-PGF1αwas totoal dramatically increased in S group after anesthesia(P<0.01).Discussion:TXB2 and 6-Keto-PGF1αwere significantly increased after pneumoperitoneum 20 minutes. It is just evident that laparoscopic surgery induces release of TXA2,PGI2 significantly increased, has powerful stress reaction. The increasing IAP and hypercapnia descrease visceral bloodflow, causing TXA2,PGI2 increased; Oxyradical can cause synthesis of TXA2 and PGI2 quickly increased.Besides, changes of IAP and intrathoracic pressure induce blood turbulent current, can also cause the release of TXA2 and PGI2 increased.SBP,DBP,TXB2 were significantly descreased after pneumoperitoneum 20 minutes in S group, comparing with F group.The result demonstrates that repressed effect of sufentanil on cardiovascular system's stress reaction, causing by laparoscopic cholecystectomy, outweighs fentanyl. The major reason is that sufentanil descreased the level of plasma catecholamine,β-endorphine and ADH, by influencing hypothalamus vasomotor centre and excitation ofsympathetic nerve.In addition,the effect of sufentanil descreasing systemic vasocular resistation superior to fentanyl is another reason.6-Keto-PGF1αin S group was significantly increased prepneumoperitoneum, comparing with before anesthesia(P<0.05);and was significantly increased after removing pneumoperitoneum 10 minutes , comparing with F group(P<0.05), while TXB2/6-Keto-PGF1αwas significantly descreased(P<0.01),so it's thought that sufentanil could induce PCI2 increased, relaxing vessels,and improving organ blood flow.TXB2 and 6-Keto-PGF1αin F group were missed balance after pneumoperitoneum 20 minutes and after removing pneumoperitoneum 10 minutes, degree of platelet activation increased, promoted platelet aggregation and vasoconstriction, thus could cause vasospasm and thrombogenesis easily. The rate of TXB2/6-Keto-PGF1αwas relative stabilization in S group, could lessen visceral vasoconstriction which caused by pneumoperitoneum. Therefore, we think that sufentanil is benefit to improve visceral microcirculatory infusion during LC. This results also suggests that maybe the direct relaxation vasocular muscle of sufentanil causes the rate of TXB2/6-Keto-PGF1αdescreased before pneumoperitoneum,thus partially'offseted'the effect of LC.In summary, compared to fentanyl, sufentanil maintains the relative balance of plasma TXA2,PGI2, by hightening plasma PGI2,strenghthens vasorelaxation and repression effect of platelet aggregation, thus improves microcirculatory infusion, reduces injury caused by laparoscope, profits patients'recovery.