目标心率导向右美托咪定静脉输注对老年高危患者腹腔镜结直肠癌术后心肌损伤的影响OA

Objective To observe the effect of target heart rate(HR)-guided intravenous infusion of dexmedetomi-dine on myocardial injury after laparoscopic colorectal cancer surgery in high-risk elderly patients.Methods A prospective study was conducted on 82 high-risk elderly patients scheduled for laparoscopic colorectal cancer surgery.They were ran-domly divided into three groups:dexmedetomidine group(group D,n=28),esmolol group(group E,n=26),and con-ventional management group(group C,n=28).Five minutes after the induction of anesthesia,patients in the groups D and E received intravenous infusions of dexmedetomidine at 0.5 μg/(kg·h)and esmolol at 30 μg/(kg·min),respectively.The infusion rate was adjusted intraoperatively according to the target HR(50-70 beats/min).Patients in the group C re-ceived conventional hemodynamic management during surgery.HR and mean arterial pressure(MAP)were recorded before induction of anesthesia(T0),immediately after tracheal intubation(T1),5 min(T2),30 min(T3),and 60 min(T4)after pneumoperitoneum,5 min after desufflation(T5),and at the end of surgery(T6).The rate-pressure product(RPP)was calculated.Radial artery blood samples were collected at T0,T4,and T6 to measure serum norepinephrine(NE),cor-tisol(Cor),and blood glucose(Glu).Serum high-sensitivity cardiac troponin T(hs-cTnT),interleukin-6(IL-6),and high-sensitivity C-reactive protein(hs-CRP)were measured preoperatively and on postoperative day 1 and 2.Intraoperative adverse events(hypotension/hypertension,bradycardia/tachycardia,premature ventricular contractions,and myocardial is-chemia)and postoperative cardiovascular events were recorded.Results Compared with the group C,HR in the groups D and E was lower from T2 to T6(all P＜0.05),and MAP and RPP in the group D were lower at T2-T6(all P＜0.05).Com-pared with the group E,HR in the group D was lower at T2 and T4-T6,and MAP and RPP were lower at T2-T6(all P＜0.05).Compared with the group C,serum NE levels at T4 and T6 and serum Cor and Glu levels at T4 were significantly lower in groups D and E(all P＜0.05).Compared with the group E,serum NE at T6 and serum Cor at T4 and T6 were sig-nificantly lower in the group D(all P＜0.05).Compared with the group C,serum hs-cTnT,IL-6,and hs-CRP levels were lower in the group D on postoperative day 1 and 2(all P＜0.05),while in the group E,only serum hs-cTnT was lower on postoperative day 1(P＜0.05).Serum hs-cTnT,IL-6,and hs-CRP levels in the group D were significantly lower than those in the group E at all postoperative time points(all P＜0.05).The incidences of intraoperative hypertension,tachycardia,and myocardial ischemia in the group D were lower than those in the group C(all P＜0.05).No significant difference was found in the incidence of postoperative cardiovascular events among the three groups(P＞0.05).Conclusions Target HR-guided intravenous infusion of dexmedetomidine is effective for anesthesia management in highrisk elderly patients undergo-ing laparoscopic colorectal cancer surgery.It can effectively maintain intraoperative hemodynamic stability,inhibit stress and inflammatory responses,and reduce postoperative myocardial injury.