BACKGROUND: Most surgeons prefer delivering cardioplegia alternatively via the aortic root and coronary sinus in patients undergoing coronary artery bypass graft surgery (CABG). Recently, some surgeons have delivered cardioplegia via the grafted vessel to the obstructed right coronary artery in order to preserve right ventricular function whenever retrograde cardioplegia is delivered. Thus, we have compared the effect on right ventricular preservation between the aforementioned two methods after cardiopulmonary bypass in patients undergoing a right CABG. METHODS: Twenty-eight patients undergoing an elective CABG with significant right coronary artery obstructive disease were allocated into 2 groups. In the alternative cardioplegia delivery group (A-group), cold blood cardioplegia was delivered via the aortic root and coronary sinus alternatively. In the simultaneous cardioplegia delivery group (S-group), cold blood cardioplegia was delivered via the coronary sinus and grafted vessel to the obstructed right coronary artery simultaneously. Hemodynamic measurements were obtained pre-bypass, at pericardial closure and at sternal closure. Data recorded included right ventricular ejection fraction, right ventricular volume index and right and left ventricular hemodynamics. RESULTS: There was no significant difference in the right ventricular ejection fraction between the two groups at pre-bypass, pericardial closure and sternal closure. In both groups, the right ventricular ejection fraction and cardiac index were not decreased, and the left ventricular ejection fraction was higher at pericardial closure than pre-bypass. However, in both groups, there was a decrease in the right andleft ventricular stroke work index and right ventricular stroke volume index at sternal closure. CONCLUSIONS: We have concluded that simultaneous cardioplegia delivery via the coronary sinus and grafted vessel to the obstructed right coronary artery was not superior to the alternative cardioplegia delivery via the aortic root and coronary sinus for preservation of right ventricular function in patients undergoing a right CABG.
Cardiopulmonary Bypass ; Coronary Artery Bypass* ; Coronary Sinus ; Coronary Vessels* ; Heart Arrest, Induced* ; Hemodynamics ; Humans ; Stroke ; Stroke Volume ; Transplants ; Ventricular Function, Right

BACKGROUND: The use of positive end expiratory pressure (PEEP) in patients with acute lung injury (ALI) improves arterial oxygenation by alleviating pulmonary shunting, helping the respiratory muscles to decrease the work of breathing, decreasing the rate of infiltrated and atelectatic tissues, and increasing functional residual capacity. In a rabbit model of saline lavage-induced ALI, we examined the effects of PEEP on gas exchange, hemodynamics, and oxygenation during high frequency jet ventilation (HFJV), and then compared these parameters with those during conventional mechanical ventilation (CMV). METHODS: Twelve rabbits underwent repeated saline lavage to create ALI. The animals were divided in 2 groups: 1) Group CMV (n = 6), and 2) Group HFJV (n = 6). In both groups, we applied 2 levels of PEEP (5 cmH2O and 10 cmH2O) and then measured the arterial blood gas, mixed venous blood gas, and hemodynamic parameters. RESULTS: With administration of PEEP of either 5 cmH2O or 10 cmH2O, the arterial oxygen content of both groups was increased, although without statistically significant differences between groups. On the contrary, the arterial carbon dioxide content was significantly decreased in the HFJV group, as compared with the CMV group, during the entire experiment. Furthermore, there was significant decreases in mean arterial pressures in both groups with a PEEP of 10 cmH2O. CONCLUSIONS: The application of PEEP in rabbits with ALI effectively improves oxygenation in either HFJV or CMV.
Acute Lung Injury ; Animals ; Arterial Pressure ; Carbon Dioxide ; Functional Residual Capacity ; Hemodynamics ; High-Frequency Jet Ventilation ; Humans ; Oxygen ; Positive-Pressure Respiration ; Rabbits ; Respiration, Artificial ; Respiratory Muscles ; Therapeutic Irrigation ; Work of Breathing

BACKGROUND: Preoperative beta-adrenergic receptor (beta-AR) antagonist administration is known to improve ventricular function by decreasing the myocardial oxygen demand in coronary artery obstructive disease (CAOD). This study evaluated the effect of preoperative propranolol on response to beta-AR agonist, dobutamine in patients undergoing off-pump coronary artery bypass graft surgery (CABG). METHODS: Twenty six patients undergoing off-pump CABG, and treated with propranolol preoperatively, were enrolled in this study. After anesthesia, the infusion of dobutamine was started at 2microgram/kg/min (D2) for 5 min and then increased to 4microgram/kg/min (D4) and 8microgram/kg/min (D8) in succession. The same protocol was performed twice before and after coronary artery anastomosis (pre-graft and post-graft). Hemodynamic variables were measured just before the infusion of dobutamine (D0, baseline) and after each dobutamine infusion at D2, D4 and D8. RESULTS: No significant change was observed in the cardiac index (CI) during the pre-graft period, but CI increased significantly at D4 and D8 compared with D0 during the post-graft period. Mean arterial pressure (MAP), mean pulmonary artery pressure (MPAP) and systemic vascular resistance index (SVRI) increased at D2, D4 and D8 and heart rate (HR) decreased at D2 and D4 during the pre-graft period. MAP and SVRI did not change and HR and CI increased at D4 and D8 during the post-graft period. The % change of CI from D0 significantly increased at D4 and D8 during the post-graft period than during the pre-graft period but not at D2. MAP, SVRI and MPAP after dobutamine infusion significantly increased during the pre-graft period than during the post-graft period. HR showed a reversed trend. CONCLUSIONS: Dobutamine infusion did not exert any known positive inotropic effect, besides increased MAP, MPAP and SVRI, in patients treated with propranolol preoperatively undergoing off-pump CABG during the pre-graft period. Meanwhile, dobutamine exerted slight inotropic effects during the post-graft period. Cautious use of dobutamine during the pre-graft period is needed in patients treated with propranolol preoperatively.
Anesthesia ; Arterial Pressure ; Coronary Artery Bypass, Off-Pump* ; Coronary Vessels ; Dobutamine* ; Heart Rate ; Hemodynamics ; Humans ; Oxygen ; Propranolol* ; Pulmonary Artery ; Transplants* ; Vascular Resistance ; Ventricular Function

BACKGROUND: Femoral to radial arterial pressure gradient (deltaP) often develops after cardiopulmonary bypass (CPB) where radial artery pressure (RAP) does not reflect the actual perfusion pressure. Renin-angiotensin system antagonists (RAS-A) are increasingly prescribed preoperatively which causes vasodilation and vascular remodeling. We evaluated the effect of RAS-A medication on ?P after CPB in patients undergoing valvular heart surgery. METHODS: Eighty-five patients scheduled for elective valvular heart surgery for regurgitant lesions were divided into two groups: the RAS-A group, in which patients were on RAS-A preoperatively (n = 52) and the control group (n = 33). Hemodynamic variables including RAP, femoral arterial pressure (FAP), body temperature, and hematocrit were recorded at after induction of anesthesia, pre-and post-CPB and sternum closure. RESULTS: After CPB, systolic deltaP was significantly greater in the RAS-A group than in the control group. Nine (27%) and 36 (69%) patients after CPB, and 6 (18%) and 23 (44%) patients after sternum closure developed systolic deltaP more than 10 mmHg, in the control and RAS-A group, respectively, which were statistically significant. Body temperature, hematocrit and systemic vascular resistance index were not different between groups. CONCLUSIONS: Preoperative treatment with RAS-A resulted in clinically significant deltaP after cardiopulmonary bypass in about 70% of patients undergoing valvular heart surgery. Concomitant monitoring of FAP with RAP might be helpful to prevent inadequate vasopressor therapy guided by inaccurate RAP after CPB in this subset of patients.
Anesthesia ; Arterial Pressure* ; Body Temperature ; Cardiopulmonary Bypass* ; Heart* ; Hematocrit ; Hemodynamics ; Humans ; Perfusion ; Radial Artery ; Renin-Angiotensin System* ; Sternum ; Thoracic Surgery* ; Vascular Resistance ; Vasodilation

BACKGROUND: Hydroxyethyl starch (HES) effectively restores plasma volume and thereby enhances microcirculation and tissue oxygenation at the expense of coagulation impairment. These effects are related to molecular weight, substitution and C2:C6 ratio. But, most of the studies regarding coagulation impairment in cardiac surgeries were performed in patients undergoing cardiopulmonary bypass which significantly causes coagulation derangements. Therefore, we have evaluated the effects of 2 different HES solutions on tissue oxygenation and postoperative bleeding in patients undergoing off-pump coronary artery bypass surgery (OPCAB). METHODS: Forty four patients were prospectively enrolled. After the induction of anesthesia, either HES 130/0.4 (V group) or 200/0.5 (H group) were infused for fluid therapy to maintain predetermined urine output, cardiac index and filling pressure up to 16 h after the surgery. Tissue oxygenation profiles and respiratory parameters were recorded after induction of anesthesia, completion of distal anastomosis and sternum closure, upon admission at intensive care unit, and 4 h thereafter. The amounts of chest tube drainage, transfusion and fluid balance were measured up to 16 h after the surgery. RESULTS: Patients' demographic data were similar between the groups. Tissue oxygenation profiles, respiratory parameters, hemodynamics, and time to extubate were not different between the groups. However, chest tube drainage and transfusion requirements were significantly less in the V group. CONCLUSIONS: In OPCAB, 6% HES 130/0.4 causes less postoperative bleeding and transfusion requirement and has a comparable efficacy on hemodynamic stability, pulmonary function and tissue oxygenation when compared to 6% HES 200/0.5.
Anesthesia ; Cardiac Output ; Cardiopulmonary Bypass ; Chest Tubes ; Coronary Artery Bypass, Off-Pump* ; Drainage ; Fluid Therapy ; Hemodynamics ; Hemorrhage* ; Humans ; Intensive Care Units ; Microcirculation ; Molecular Weight ; Oxygen* ; Plasma Volume ; Prospective Studies ; Starch* ; Sternum ; Water-Electrolyte Balance

Although numerous studies have validated the efficacy of intracoronary shunt on reducing left ventricular dysfunction during off-pump coronary artery bypass surgery (OPCAB), there is lack of evidence supporting its role on right ventricular (RV) function during right coronary artery (RCA) revascularization. Therefore, we studied the effect of intracoronary shunt during grafting of dominant RCA without visible collateral supply on global RV function using thermodilution method. Forty patients scheduled for multivessel OPCAB with right dominant coronary circulation without collateral supply confirmed by angiography were randomized to RCA revascularization either with a shunt (n=20) or soft snare occlusion (n=20). RV ejection fraction (RVEF) was recorded at baseline, during RCA grafting, and 15 min after reperfusion. Corresponding RV stroke work index (RVSWI) was calculated. RVEF and RVSWI decreased significantly during RCA grafting and returned to baseline values after reperfusion in both groups without any significant differences between the groups. Intracoronary shunt did not exert any beneficial effect on global RV function during RCA grafting, even in the absence of visible collateral supply. Regarding the possibility of graft failure by intracoronary shunt-induced endothelial damage, routine use of intracoronary shunt during RCA grafting is not recommended in patients with preserved biventricular function.
Aged ; Blood Pressure ; *Collateral Circulation ; Coronary Artery Bypass, Off-Pump/*methods ; Coronary Artery Disease/physiopathology/*surgery ; *Coronary Circulation ; Female ; Heart Rate ; Humans ; Male ; Middle Aged ; Norepinephrine/administration & dosage ; Prospective Studies ; Stroke Volume ; Sympathomimetics/administration & dosage ; Thermodilution ; *Ventricular Function, Right

BACKGROUND: It is important to assess cardiac preload for management of patients undergoing off pump coronary artery bypass surgery (OPCAB). Recently, several studies have documented the good correlation between right ventricular end-diastolic volume index (RVEDVI) and stroke volume index (SVI), compared with cardiac filling pressures. However, none of these studies have evaluated relationship between predictors of preload and SVI measured with volumetric pulmonary artery catheter during OPCAB. The correlation of continuous RVEDVI and SVI measured with volumetric pulmonary artery catheter during OPCAB was evaluated in this study. METHODS: Fifty three patients undergoing OPCAB were included. Hemodynamic parameters were measured 10 min after induction (T1), 10 min after Y-graft formation started (T2) and 10 min after sternum closure (T3). The correlation of parameters were assessed by simple linear regression. RESULTS: Central venous pressure (CVP) and pulmonary artery occlusion pressure (PAOP) did not correlate with SVI during OPCAB. On the other hand, a statistically significant result was found between RVEDVI and SVI at T2 (r(2)=0.133, P=0.007) and T3 (r(2)=0.380, P < 0.000). But RVEDVI and SVI were weakly correlated. And at T1, RVEDVI and SVI did not correlate. CONCLUSIONS: RVEDVI is a more reliable predictor of preload compared to CVP and PAOP during OPCAB. But in post-induction period (T2), RVEDVI did not correlate with SVI.
Catheters* ; Central Venous Pressure ; Coronary Artery Bypass, Off-Pump* ; Hand ; Hemodynamics ; Humans ; Linear Models ; Pulmonary Artery* ; Sternum ; Stroke Volume* ; Stroke*

BACKGROUND: Although female gender is associated with higher prevalence of perioperative morbidity and mortality than male gender in conventional coronary artery bypass surgery (CABG) using cardiopulmonary bypass, the impact of gender as an independent risk factor for morbidity and mortality following off-pump CABG (OPCAB) is controversial. Therefore, we prospectively investigated the impact of gender on intraoperative variables and postoperative outcome and complications in OPCAB. METHODS: One hundred patients (69 males and 31 females) undergoing OPCAB by a single cardiac surgeon during 5 months period were prospectively enrolled. Preoperative patient's characteristics, intraoperative hemodynamics and medications and postoperative outcome and complications were recorded during hospital stay. RESULTS: There were no significant differences in preoperative characteristics including age, NYHA class and incidence of concomitant diseases between the male and female groups, except body surface area which was less in the female group. There were no significant differences in intraoperative hemodynamics and use of cardiotonic drugs between the groups. Frequency and amount of blood transfusion were greater, and length of ventilatory care and stay in intensive care unit were longer in female group. Other postoperative outcomes were similar between the groups. CONCLUSIONS: Gender did not significantly affect postoperative outcome, except use of blood products, length of ventilatory care and stay in intensive care unit in OPCAB. These results may be attributable to comparable preoperative patient's characteristics between the groups.
Blood Transfusion ; Body Surface Area ; Cardiopulmonary Bypass ; Cardiotonic Agents ; Coronary Artery Bypass ; Coronary Artery Bypass, Off-Pump* ; Female ; Hemodynamics ; Humans ; Incidence ; Intensive Care Units ; Length of Stay ; Male ; Mortality ; Prevalence ; Prospective Studies ; Risk Factors

No abstract available.
Circulatory Arrest, Deep Hypothermia Induced ; Thoracic Surgery

Intraoperative transesophageal echocardiography (TEE) during cardiac surgery is an invaluable procedure, which aids hemodynamic management as well as surgical directions. TEE adds valuable information to the assessment of cardiac structures and in contrast to transthoracic echocardiography (TTE), due to its proximity to left atrium (LA), it is especially useful in detection of mass lesions in the LA. The following case describes a patient undergoing aortic valve replacement under cardiopulmonary bypass with low risk of thrombi formation and undetected thrombi in the LA appendage by preoperative TTE. These thrombi could be detected by intraoperative TEE and removed at the same operation, thus avoiding thromboembolic complication and second operation.
Aortic Valve* ; Cardiopulmonary Bypass* ; Echocardiography ; Echocardiography, Transesophageal* ; Heart Atria ; Hemodynamics ; Humans ; Thoracic Surgery ; Thrombosis ; Weaning*