ABSTRACT
Objective To compare the effects of dobutamine with those milrinone on myocardial strain in patients undergoing valve replacement surgery.Methods Fifty-five patients udergoing valve replacement surgery, 27 males and 28 females, aged 40-75 years, falling into ASA physical statusⅡ orⅢ, New York Heart Association (NYHA) ⅡorⅢ, were included in this study.They were divided into 3 groups by using a random number table:intravenous infusion dobutamine group (group D, n=18), intravenous infusion milrinone group (group M, n=20) and intravenous infusion saline group (group C, n=17).All patients were used general anesthesia.In groups D, the patients received intravenous infusion dobutamine (4μg·kg-1·min-1) for an hour starting from 15 min after termination of CPB.In group M, the patients did intravenous infusion milrinone (0.4μg·kg-1·min-1) in the same way.In group C, the patients got intravenous infusion saline also.After induction of anesthesia, these patients were recorded for hemodynamic measurement at three points after induction of anesthesia and before splitting of sternum (T0), starting from 15 min after termination of CPB (T1), intravenous infusion medicine for 30 min (T2), intravenous infusion medicine for one hour (T3):HR, CVP, cardiac output (CO), left ventricular ejection fraction (LVEF), right ventricular fractional area change (RVFAC), cardiac index (CI) and systemic vascular resistance index (SVRI) and strained indicator:global longitudinal strain of left ventricle (S-LVL), global circumferential strain of the left ventricle (S-LVM), global longitudinal strain of right ventricle (S-RV).Results Compared with group M, HR in group D at T2 and T3 was higher (P<0.05).Compared with group C, HR in group D at T3 was higher (P<0.05).And CI in group D at T2 was higher than that in groups C and M (P<0.05).Compared with groups C, S-LVMin groups D and M at T2 and T3 were stronger, S-LVL, S-RV in group D and S-RV in group M at T3 were stronger (P<0.05).Conclusion Intravenous infusion dobutamine can improve S-LVM, S-LVLand S-RV;Intravenous infusion milrinone can improve S-LVMand S-RV.
ABSTRACT
Objective To evaluate the effect of dobutamine or milrinone on intraventricular syn-chronization in the patients undergoing cardiac valve replacement with cardiopulmonary bypass ( CPB). Methods Sixty American Society of Anesthesiologists physical status Ⅱ or Ⅲ patients of both sexes, aged 40-75 yr, of New York Heart AssociationⅡorⅢ, scheduled for elective cardiac valve replacement with CPB, were divided into 3 groups (n＝20 each) using a random number table: control group ( group C), dobutamine group ( group D) and milrinone group ( group M). Dobutamine 4 μg·kg-1·min-1was intravenously infused for 60 min starting from 15 min after termination of CPB in group D. Milrinone 0. 4 μg·kg-1·min-1was intravenously infused for 60 min starting from 15 min after termination of CPB in group M. The equal volume of normal saline was given instead in group C. The parameters of heart function were monitored using transesophageal echocardiography. After induction of anesthesia and before splitting the sternum (T0), at 15 min after termination of CPB (T1), and at 30 and 60 min of dobutamine, milri-none or normal saline infusion (T2, average value at two time points), the parameters of intraventricular synchronization were calculated with QLAB software (9. 1 version): standard deviation of time to peak sys-tolic velocity of the left ventricular longitudinal strain 7 segments (LVSDt-L), standard deviation of time to peak systolic velocity of the right ventricular longitudinal strain 7 segments (RVSDt), standard deviation of time to peak systolic velocity of the left ventricular circumferential strain 6 segments (LVSDt-C). Results Compared with group C, LVSDt-C, LVSDt-L and RVSDt were significantly decreased at T2in group D (P＜0. 05), and no significant change was found in the indices mentioned above at each time point in group M (P＞0. 05). RVSDt was significantly higher at T2in group M than in group D ( P＜0. 05). Compared with the baseline at T0, LVSDt-L was significantly increased at T2in group C, and RVSDt was significantly in-creased at T2in group M ( P＜0. 05). Conclusion Intravenously infusing dobutamine after CPB can im-prove the ventricular synchronization, however, intravenously infusing milrinone may increase the right ventricular asynchronization in the patients undergoing cardiac valve replacement.
ABSTRACT
Objective To investigate the effects of intravenous infusion of methoxamine and phenylephrine on blood pressure and coronary artery blood flow in elderly patients with post volume treatment hypotension after cardiopulmonary bypass (CPB ) undergoing coronary artery bypass grafting (CABG).Methods Forty patients,physical status ASA Ⅱ or Ⅲ,>65 years old,undergo-ing CABG,following CPB,with a mean arterial pressure (MAP)<70% of baseline,despite adequate volume replacement (based on achieving a normal CVP),were randomly assigned to me-thoxamine group (group M,n=20)or phenylephrine group (group P,n=20).The initial infusion rate was 3 μg·kg-1·min-1in group M and 0.24 μg·kg-1·min-1in group P,respectively.The rate was increased or decreased by one third of initial dose in order to maintain the MAP at the target level (±20% of baseline MAP).Coronary sinus (CS),systolic blood flow velocity time integral (SV-TI),diastolic velocity time integral (DVTI),CS blood flow (CSBF)were recorded before adminis-tration,at 3,5,10,15,30 min after administration.Results Compared with pre-administration,SV-TI,DVTI,CSBF were increased at each point in the two groups (P<0.05 or P<0.01).SVI was in-creased at 15 min and 30 min in group M (P<0.05).Compared with group P,DVTI and CSBF at 10,15 min and 30 min was higher in group M (P<0.05 or P<0.01).There were 2 cases of atrial fibrillation and 1 case of frequent ventricular premature beat after operation in group M;1 case of bradycardia and 1 case of frequent ventricular premature beats after operation in group P.Conclusion Intravenous infusion of methox-amine and phenylephrine both can correct post volume treatment hypotension after CPB in elderly patients undergoing CABG,but methoxamine increases coronary blood flow more significantly and may be more ben-eficial to patients with coronary heart disease.