Fresh Frozen Plasma in Pump Priming for Congenital Heart Surgery: Evaluation of Effects on Postoperative Coagulation Profiles Using a Fibrinogen Assay and Rotational Thromboelastometry

PURPOSE: In this prospective study, the effects of fresh frozen plasma (FFP) included in pump priming for congenital heart surgery in infants and children on post-bypass coagulation profiles were evaluated. MATERIALS AND METHODS: Either 20% albumin (50-100 mL) or FFP (1-2 units) was added to pump priming for patients randomly allocated into control or treatment groups, respectively. Hematologic assays, including functional fibrinogen level, and rotational thromboelastometry (ROTEM(R)) were measured before skin incision (baseline), after weaning from cardiopulmonary bypass (CPB) and heparin reversal, and at 24 hours (h) in the intensive care unit (ICU). RESULTS: All the baseline measurements were comparable between the control and treatment groups of infants and children. After heparin reversal, however, significantly higher fibrinogen levels and less reduced ROTEM parameters, which reflect clot formation and firmness, were demonstrated in the treatment groups of infants and children. At 24 h in the ICU, hematologic assays and ROTEM measurements were comparable between the control and treatment groups of infants and children. Transfusion requirements, excluding FFP in pump prime, and postoperative bleeding were comparable between the control and treatment groups of infants and children. CONCLUSION: Although clinical benefits were not clearly found, the inclusion of FFP in pump priming for congenital heart surgery in infants and children was shown to improve the hemodilution-related hemostatic dysfunction immediately after weaning from CPB and heparin reversal.

Effect of Intracoronary Shunt on Right Ventricular Function During Off-pump Grafting of Dominant Right Coronary Artery with Poor Collateral

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.

Changes in hemodynamic parameters and regional myocardial perfusion measured by thermal diffusion probe from the infusion of norepinephrine during displacement of porcine beating heart / 대한마취과학회지

BACKGROUND: This study was done to evaluate the sole effect of norepinephrine on the regional myocardial perfusion during displacement of the porcine beating heart using thermal diffusion method. METHODS: Thermal diffusion probe was inserted into the anterior myocardial wall during 20 procedures in 10 male pigs (30-35 kg). The measurements of regional myocardial perfusion and hemodynamic parameters were performed after complete instrumentation (baseline), after displacement of the beating heart anteriorly, and 5 and 15 minutes after norepinephrine infusion, titrated to restore baseline mean arterial pressure (MAP). RESULTS: Norepinephrine infusion reversed the decrease in MAP and myocardial perfusion, caused by displacement of the beating heart (62 +/- 3% to 115 +/- 4% of baseline, P < 0.01; 41 +/- 5% to 125 +/- 4% of baseline, P < 0.05, respectively). CONCLUSIONS: Restoration of MAP with norepinephrine infusion without any preload augmentation reversed deterioration in regional myocardial perfusion during displacement of the porcine beating heart.

The Effect of Hydroxyethyl Starch and Crystalloid Solutions on Blood Loss and Transfusion Requirement in Patients with Recent Antiplatelet Therapy Undergoing Off-pump Coronary Bypass Surgery / 대한마취과학회지

BACKGROUND: Hydroxyethylstarch (HES) solutions are commonly used for intravascular volume expansion with varying effect on coagulation depending on molecular weight and mode of hydroxyl substitution.Clopidogrel and aspirin have been shown to reduce cardiovascular complications in patients with coronaryartery occlusive disease which renders patients to higher risk of bleeding complications who require surgery.The purpose of this study was to evaluate the effect of HES 200/0.5, 130/0.4 and crystalloid on blood loss and transfusion requirement in patients with recent antiplatelet therapy undergoing off-pump coronary bypass surgery (OPCAB) in a prospective, randomized trial. METHODS: Sixty patients scheduled for OPCAB, who received clopidogrel and aspirin within 5 days of surgery were randomly allocated into 3 groups:HES 200/0.5 (n = 20), HES 150/0.4 (n = 20), and Crystalloid (n = 20).Routine coagulation profile were measured before and 2 days after the surgery.Amount of perioperative blood loss, transfusion requirement and fluids input and output were recorded until 2 days postoperatively. RESULTS: The 3 groups were similar with regard to patients and operative characteristics.There were no significant differences in the amount of perioperative blood loss and transfusion requirement among the 3 groups. CONCLUSIONS: Both HES solutions were safe to use in terms of blood loss and transfusion requirement in patients undergoing OPCAB who received antiplatelet agents within 5 days of surgery.

The Effect of 6% Hydroxyethyl Starch 130/0.4 on Hemostasis and Hemodynamic Efficacy in Off-pump Coronary Artery Bypass Surgery: a Comparison with 6% Hydroxyethyl Starch 200/0.5 / 대한마취과학회지

BACKGROUND: This study was designed to compare the effect of low-molecular 6% hydroxyethyl starch (HES) 130/0.4 on hemostasis and hemodynamic efficacy with that of medium-molecular 6% HES 200/0.5 in patients undergoing off-pump coronary artery bypass surgery. METHODS: Forty-eight patients were randomized to receive up to 33 ml/kg of either 6% HES 130/0.4 or 6% HES 200/0.5. Hemodynamic variables and blood tests including thromboelastography were measured 10 min after induction (baseline value, T0), 5 min after acute loading of HES 10 ml/kg (T1) in hypovolemic patients, after sternum closure (T2), and 16 hr after intensive care unit (ICU) arrival (T3). Chest tube drainage was recorded until 16 hours after ICU arrival. RESULTS: Hemodynamic variables were similar in both groups. Chest tube drainage at 16 hr after surgery was higher in HES 200/0.5 group than that in HES 130/0.4 group. Maximum clot firmness was decreased in HES 200/0.5 group at sternal closure but not in HES 130/0.4 group. CONCLUSIONS: Both HES 200/0.5 and HES 130/0.4 were equally efficient in maintaining stable hemodynamics during off-pump coronary artery bypass surgery. However, HES 130/0.4 may reduce postoperative blood loss compared to that of HES 200/0.5 at the same dose of 33 ml/kg.

A Comparison of the Effects of Histidine-tryptophan-ketoglutarate Solution versus Cold Blood Cardioplegic Solution on Myocardial Protection in Mitral Valve Surgery / 대한흉부외과학회지

BACKGROUND: Ischemia-reperfusion injury related to unsuccessful myocardial protection affects postoperative ventricular function and mortality during open-heart surgery. We prospectively compared the effects of administration of histidine-tryptophan-ketoglutarate (HTK) solution and cold blood cardioplegia (CBC) on myocardial protection and clinical outcome in patients undergoing mitral valve surgery. MATERIAL AND METHOD: Seventy patients with mitral regurgitation (MR) undergoing mitral valve surgery were randomly divided into the HTK group (n=31) and the CBC group (n=31); eight patients were excluded. Perioperative hemodynamics, cardiac medications, pacing, postoperative outcomes and complications were recorded during the hospital stay. All patients received follow-up for at least 6 months postoperatively for morbidity and mortality. RESULT: There were no significant differences in the hemodynamics between the groups during the study period, except for the mean pulmonary artery pressure (MPAP), PCWP and CVP that were lower in the HTK group at 15 min after weaning of CBP. There were no differences for inotropic support and pacing during the 12 hrs postoperatively between the groups. CK-MB values on day 1 and day 2 were 77+/-54 and 41+/-23 for the HTK group and 70+/-69 and 44+/-34 for the CBC group, respectively (p=NS). Postoperative clinical outcomes were similar in both groups for at least 6 months during the follow-up period. CONCLUSION: These results suggest that the use of HTK solution is as safe as cold blood cardioplegia in terms of myocardial protection.

Effect of Gender on Outcomes of Off-pump Coronary Artery Bypass Surgery / 대한마취과학회지

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.

Effect of Preoperative Renin-Angiotensin System Antagonists on the Difference between Radial and Femoral Arterial Pressure after Cardiopulmonary Bypass in Patients Undergoing Valvular Heart Surgery / 대한마취과학회지

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.

Does Predictors of Preload Measured from Continuous Right Ventricular End-diastolic Volume Index Monitored Pulmonary Artery Catheter Reflect Stroke Volume Index in Off Pump Coronary Artery Bypass? / 대한마취과학회지

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.

The Effects of 6% Hydroxyethyl Starch (HES) 130/0.4 and 6% HES 200/0.5 on Tissue Oxygenation and Postoperative Bleeding in Patients undergoing Off-pump Coronary Artery Bypass Surgery / 대한마취과학회지

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.

Early Hemodynamic Changes and Short-term Outcomes of Mitral Valvuloplasty versus Replacement with Chordal Preservation for Patients with Mitral Regurgitation / 대한흉부외과학회지

BACKGROUND: Preserving the subvalvular apparatus after mitral valve replacement (MVR) results in better ventricular function and a better outcome. In conjunction, mitral valve repair (MVr) is associated with a better outcome, yet little is known about the hemodynamics and outcomes between patients undergoing MVr and MVR with chordal preservation. We prospectively evaluated the hemodynamic changes and outcomes of patients undergoing MVr and MVR with chordal preservation. MATERIAL AND METHOD: Fifty-four patients with mitral regurgitation (MR) who underwent MVR with chordal preservation (n=21) or MVr (n=33) were studied. The patients' characteristics, the intra- and postoperative hemodynamics and the use of cardiac medications, the postoperative outcome and the complications were recorded during the hospital stay. All the patients were followed up for at least 6 months postoperatively for determining their morbidity and mortality. RESULT: The patients' characteristics were similar between the groups, except for the presence of atrial fibrillation and congestive heart failure which was more frequent in the MVR group. Also, the preoperative left ventricular ejection fraction was lower in the MVR group than in the MVr group (64+/-9% versus 69+/-5%, respectively, p=0.043). There were no significant differences of the hemodynamics between the groups. The use of inotropic drugs and pacemakers during the 12hrs postoperatively was more common in the MVR group than in the MVr group (48% versus 24%, p=0.025 and 52% versus 24%, p=0.035, respectively). The other postoperative outcomes were similar in both groups for at least the 6 months follow-up period. CONCLUSION: MVR with chordal preservation was comparable with regard to the hemodynamics and clinical outcomes, supporting the beneficial effect of preserving the subvalvular apparatus after MVR.

Left Atrial Thrombi Detected by Intraoperative Transesophageal Echocardiography after Weaning from Cardiopulmonary Bypass for Aortic Valve Replacement: A case report / 대한마취과학회지

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.

The Effect of Preoperative Propranolol Medication on Dobutamine Infusion in Off-pump Coronary Artery Bypass Graft Surgery / 대한마취과학회지

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.

The Potential of Peripheral Venous Pressure as a Substitutional Hemodynamic Parameter of Central Venous Pressure in Hypovolemic Patients with Coronary Artery Disease / 대한마취과학회지

BACKGROUND: Peripheral venous pressure (PVP) was known to have significant correlation with central venous pressure (CVP) in patients with normal and abnormal cardiac function. The purpose of this study is to evaluate the possibility of PVP as a substitute of CVP for volume status monitoring. METHODS: 41 hypovolemic patients with pulmonary capillary wedge pressure (PCWP) below 10 mmHg, scheduled for elective coronary artery bypass graft were included. CVP and PVP were measured from proximal port of pulmonary artery (PA) catheter and antecubital vein, respectively. Each was connected to the same monitoring system by rigid tubes of same length. Measurements were performed as follows: after PA catheter insertion; after increasing PCWP above 10 mmHg by I.V. fluid infusion; and after anesthesia induction. Hemodynamic variables were recorded at end-expiration after stabilizing for 5 10 minutes. For statistical analysis, Bland and Altman plot was created. RESULTS: The overall mean bias between CVP and PVP was 0.7 mmHg (95% confidence interval, 1 0.5). Limits of agreement of mean bias was 2.1 3.6 mmHg. 118 out of 121 PVP measurements were within the ranges of CVP +/- 3 mmHg (98%). The direction of CVP change was predicted by PVP in 68%. However, larger changes of PVP (> or = 2 mmHg) predicted the changes of CVP with increased accuracy (90%). There were only 5 cases that CVP and PVP had changed in opposite direction. CONCLUSIONS: In conclusion, PVP has a potential to be a substitutional hemodynamic parameter of CVP.

Effect of Pulmonary Artery Pressure on Changes in Right Ventricular Function according to Norepinephrine Infusion in Patients with Valvular Heart Disease / 대한마취과학회지

BACKGROUND: Increasing coronary perfusion pressure by using a vasopressor is one of the important treatment strategies in pulmonary hypertension. In present study, we evaluated whether chronic pulmonary hypertension influences the effect of norepinephrine (NE) on right ventricular function and hemodynamic variables in patients with valvular heart disease. METHODS: Forty eight patients undergoing valve replacement surgery were divided into two groups according to pulmonary artery pressure, i.e., a control (n = 28) and a pulmonary hypertension group (n = 20). A thermodilution pulmonary artery catheter for continuous monitoring of cardiac output, right ventricular (RV) ejection fraction and RV volume was inserted before the induction of anesthesia. When systemic hypotension occurred following induction of anesthesia, norepinephrine was infused at rates of 0.03 and then 0.06microgram/kg/min for 10 minutes, respectively and hemodynamic variables were measured after anesthesia induction, and at the end point of each infusion rate. RESULTS: No significant differences occurred in systemic or pulmonary hemodynamic variables according to the infusion of norepinephrine between the two groups. And, no significant changes were observed in right ventricular performance according to the infusion of norepinephrine in two groups. CONCLUSIONS: Norepinephrine did not show different systemic or pulmonary hemodynamic effects in patients with or without chronic pulmonary hypertension. Norepinephrine did not increase the right ventricular ejection fractions or cardiac outputs of patients with chronic pulmonary hypertension.

The Comparision of Nicardipine and Sodium Nitroprusside on Postoperative Hypertension after Coronary Artery Bypass Graft Surgery / 대한마취과학회지

BACKGROUND: Hypertension following coronary artery bypass graft surgery (CABG) occurs frequently. Pharmacologic therapy of postoperative hypertension has often been treated with sodium nitroprusside (SNP). Nicardipine which is a dihydropyridine calcium-channel blocker, has little or no direct negative effects on cardiac contractility. Thus, we have compared the effects on hemodynamics between nicardipine and SNP after a CABG. METHODS: After a CABG, when systolic blood pressure (SBP) was elevated above 140 mmHg, patients were randomized to receive either nicardipine (N-group, n = 26) or SNP (S-group, n = 21) at an initial rate of 2ng/kg/min until the SBP was lowered to 120 130 mmHg (target blood pressure, TBP) for 10 minutes. If the TBP was not achieved, the infusion rates of both drugs were increased by 1ng/kg/min every 10 minutes. If SBP was lowered below 100 mmHg, phenylephrine was infused. Hemodynamic measurements were obtained just before (T1) and at 10 min (T2), 60 min (T3) and 24 h (T4) after the infusin of nicardipine or SNP. Infusion time, total doses, creatine phosphokinase (CK)-MB, plasma catecholamine and the use of phenylephrine were compared between groups. RESULTS: The SBP and systemic vascular resistance were significantly decreased in both groups. The cardiac index and stroke volume index were significantly increased at T3 in both groups but they were significantly increased only in the N-group at T2. The infusion time and the total doses of both drugs were significantly less in the N-group than the S-group. There were no significant differences in CK-MB, plasma catecholamine and the use of phenylephrine between groups. CONCLUSIONS: It has been suggested that the infusion of nicardipine is as effective as the infusion of SNP for the control of postoperative hypertension and the increase of cardiac output after a CABG. However, immediately after the drug infusion, nicardipine was superior to SNP in maintaining left ventricular performance.

The Effect of the Radius and Longitude of a Catheter in Continuous Arterial Blood Pressure Monitoring / 대한마취과학회지

BACKGROUND: Continuous arterial blood pressure monitoring is a highly effective method in an operation and the intensive care unit. However, the accuracy of the monitoring system could be influenced by the radius and longitude of the catheter. This study was executed to examine the effects of the radius and longitude of a catheter. METHODS: Forty-two pediatric patients scheduled to undergo open heart surgery were selected. After induction of anesthesia, the radial artery pressure was measured by a 22-gauge (1 inch) catheter and the femoral artery pressure was measured by a 20-gauge (1.16 inch) catheter, 22-gauge catheter and 20-gauge (12 cm) catheter in succession. Influences of the radius and longitude were analysed respectively. All values are expressed as mean +/- SD and analysed using the paired t-test; P < 0.05 was considered significant. RESULTS: The systolic pressure of the 20-gauge (1.16 inch) catheter was higher than that of the 22- gauge (1 inch) catheter. The systolic pressure of the 20-gauge (1.16 inch) catheter was higher than that of the 20-gauge (12 cm) catheter. Mean and diastolic pressures were low in the 20-gauge (1.16 inch) catheter, compared with the 20-gauge (12 cm) catheter. CONCLUSIONS: Shorter and/or larger radius catheters could increase the pulse pressure in pediatric patients.

The Effect of Simultaneous and Alternative Cardioplegia Delivery on Right Ventricular Preservation in Patients Undergoing Right Coronary Artery Bypass Graft Surgery / 대한마취과학회지

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.

The Anesthetic Management of the Patient with a Mediastinal Mass: A case report / 대한마취과학회지

General anesthesia for the removal of a large mediastinal mass has been associated with life-threatening airway obstruction. We present a case of general anesthesia for a patient with superior posterior mediastinal mass and critical airway compression who was allowed to maintain spontaneous ventilation throughout general anesthesia for a thoracotomy. The patient was a 5-year-old boy complaining of productive cough and intermittent fever for 3 weeks. His chest radiograph and magnetic resonance imaging(MRI) film demonstrated a critically narrowed and deviated trachea at the level of the thoracic inlet to the proximal portion of the right bronchus. We can secure the airway by spontaneous ventilation without muscle relaxation and allowing the patient to breathe spontaneously and insertion of endotracheal tube distal to the narrowed portion of trachea.

Reliability of Pulse Oximetry in Severe Hypoxemic Children with Congenital Heart Disease / 대한구급학회지

Introduction: Oxygen delivery to tissue is of major clinical interest in patients with cyanotic congenital heart disease (CHD). The use of pulse oximeter to monitor arterial oxygen saturation (SaO2) is considered accurate and reliable in the range of 90% to 100%. However with desaturation, the accuracy remains controversial below 90%. The aim of this study was to evaluate the accuracy of pulse oximetry in severe hypoxemia. METHOD: In 110 children with cyanotic CHD, pulse oximeter (N-200, Nellcor, USA) readings were compared with the direct measurement of SaO2 by blood gas analyser (Profile10, Stat, USA). All measurements were carried out after induction of anesthesia and devided into 4 groups according to saturation measured by pulse oximeter (SpO2). SpO2 in group I was higher than 90% (n=90), in group II between 80% and 89% (n=75), in group III between 70% and 79% (n=41), in group IV lower than 69% (n=18). Statistical analysis of paired SpO2 and SaO2 values was performed using correlation analysis and paired t-test. The other comparisons were perfomed with ANOVA. p<0.05 was considered statistically significant. RESULTS: Correlation coefficient of group I was 0.89 (p<0.01), group II was 0.67 (p<0.01), group III was 0.63 (p<0.01) and group IV was 0.41. The study demonstrate that SpO2 seems to have good correlation with SaO2 when SpO2 is higher than 70%. This results are contrary to other studies which show that SpO2 is not reliable when SpO2 is below 90%. However, the correlation value r seems to decrease with desaturation. CONCLUSION: The use of pulse oximeter in severe hypoxemic children with CHD is efficient in monitoring oxygenation, even though there is decrease in accuracy of the SpO2.