A study of the efficacy of furosemide as a prophylaxis of acute renal failure in coronary artery bypass grafting patients: A clinical trial

BACKGROUND: Renal failure is a frequent event after coronary artery bypass grafting (CABG). Hemodynamic alterations during surgery as well as the underlying disease are the predisposing factors. We aimed to study intermittent furosemide therapy in the prevention of renal failure in patients undergoing CABG. METHODS: In a single-blind randomized controlled trial, 123 elective CABG patients, 18-75 years, entered the study. Clearance of creatinine, urea and water were measured. Patients were randomly assigned into three groups: furosemide in prime (0.3-0.4 mg/kg); intermittent furosemide during CABG (0.2 mg/kg, if there was a decrease in urinary excretion) and control (no furosemide). RESULTS: There was a significant change in serum urea, sodium and fluid balance in �intermittent furosemide� group; other variables did not change significantly before or after the operation. Post-operative fluid balance was significantly higher in �intermittent furosemide� group (2573 ± 205 ml) compared to control (1574 ± 155 ml) (P < 0.010); also, fluid balance was higher in �intermittent furosemide� group (2573 ± 205 ml) compared to �furosemide in prime� group (1935 ± 169 ml) (P < 0.010). CONCLUSION: The study demonstrated no benefit from intermittent furosemide in elective CABG compared to furosemide in prime volume or even placebo. © 2015, Isfahan University of Medical Sciences(IUMS). All rights reserved

Goal-directed therapy in cardiovascular surgery: A case series study

Hemodynamic and intravascular volume monitoring has been utilized and significantly improved thanks to the technology revolution. Goal-Directed Therapy (GDT) derived from this advanced monitoring is beneficial for complex surgeries, and it shifted the medical approaches from static therapy to more personalized functional treatments. Conventional monitoring methods such as blood pressure, heart rate, urinary output, and central venous pressure are commonly used. However, studies have shown these routine parameters often cannot precisely estimate the quality of tissue perfusion. Tissue hypoperfusion and hypoxia play a crucial role in initiating a systemic inflammatory response after prolonged surgeries, resulting in unstable hemodynamic condition of the patients. Several studies reported the importance of GDT in non-cardiac surgeries and there are few reports on cardiac surgeries. However, tissue perfusion and fluid management are more critical in complex and prolonged cardiovascular surgeries to avoid complications such as low cardiac output syndrome and renal or pulmonary dysfunction. Different advanced hemodynamic monitorings have been utilized perioperatively in cardiac surgery to help decision-making on inotrope and fluid management. In this article we present 5 cases of usefulness hemodynamic monitoring in patients who underwent cardiovascular surgeries

A study of the efficacy of furosemide as a prophylaxis of acute renal failure in coronary artery bypass grafting patients: A clinical trial

BACKGROUND: Renal failure is a frequent event after coronary artery bypass grafting (CABG). Hemodynamic alterations during surgery as well as the underlying disease are the predisposing factors. We aimed to study intermittent furosemide therapy in the prevention of renal failure in patients undergoing CABG. METHODS: In a single-blind randomized controlled trial, 123 elective CABG patients, 18-75 years, entered the study. Clearance of creatinine, urea and water were measured. Patients were randomly assigned into three groups: furosemide in prime (0.3-0.4 mg/kg); intermittent furosemide during CABG (0.2 mg/kg, if there was a decrease in urinary excretion) and control (no furosemide). RESULTS: There was a significant change in serum urea, sodium and fluid balance in &ldquo;intermittent furosemide&rdquo; group; other variables did not change significantly before or after the operation. Post-operative fluid balance was significantly higher in &ldquo;intermittent furosemide&rdquo; group (2573 &plusmn; 205 ml) compared to control (1574 &plusmn; 155 ml) (P &lt; 0.010); also, fluid balance was higher in &ldquo;intermittent furosemide&rdquo; group (2573 &plusmn; 205 ml) compared to &ldquo;furosemide in prime&rdquo; group (1935 &plusmn; 169 ml) (P &lt; 0.010). CONCLUSION: The study demonstrated no benefit from intermittent furosemide in elective CABG compared to furosemide in prime volume or even placebo. &nbsp;&nbsp;</div

Perioperative risk factors for prolonged mechanical ventilation and tracheostomy in women undergoing coronary artery bypass graft with cardiopulmonary bypass

Background: Prolonged mechanical ventilation is an important recognized complication occurring during cardiovascular surgery procedures. This study was done to assess the perioperative risk factors related to postoperative pulmonary complications and tracheostomy in women undergoing coronary artery bypass graft with cardiopulmonary bypass. Methods: It was a retrospective study on 5,497 patients, including 31 patients with prolonged ventilatory support and 5,466 patients without it; from the latter group, 350 patients with normal condition (extubated in 6-8 hours without any complication) were selected randomly. Possible perioperative risk factors were compared between the two groups using a binary logistic regression model. Results: Among the 5,497 women undergoing coronary artery bypass graft (CABG), 31 women needed prolonged mechanical ventilation (PMV), and 15 underwent tracheostomy. After logistic regression, 7 factors were determined as being independent perioperative risk factors for PMV. Discussion: Age ≥70 years old, left ventricular ejection fraction (LVEF) ≤30%, preexisting respiratory or renal disease, emergency or re-do operation and use of preoperative inotropic agents are the main risk factors determined in this study on women undergoing CABG

Effect of low-dose Dopamine on lactate level in patients undergoing coronary bypass surgery

Background: The aim of this study was to study the effect of low-dose Dopamine on the blood lactate levels as a sign of visceral perfusion in coronary artery bypass graft surgery (CABG) patients. Methods: In a double-blinded, randomized clinical trial, 100 adult patients - who were candidated for elective isolated CABG surgery - were divided equally into two groups of low-dose Dopamine group (2 μg / kg / min) and control group (n=50 in each). Lactate levels, arterial blood gas analyses, blood pressure, and heart rate were recorded intraoperatively at four time points: before the induction of anesthesia; 15 minutes after the beginning of cardiopulmonary bypass (CPB); during CPB at rewarming to 34°C; and 15 minutes after separation from CPB. These biochemical and hemodynamic parameters were compared in these four time points between the two study groups. Results: Arterial blood gas and hemodynamic parameters were similar between the two groups during surgery (p values > 0.05). There were no significant differences between the lactate levels in the Dopamine and control groups at the beginning of CPB (3.1 ± 2.5 vs. 2.6 ± 2.0 mg/dl; p value = 0.453), at the time of rewarming (3.1 ± 2.5 vs. 2.6 ± 2.0 mg/dl; p value = 0.510), and after CPB (3.1 ± 2.5 vs. 2.6 ± 2.0 mg/dl; p value = 0.551) - respectively. Conclusions: The use of low-dose Dopamine did not decrease lactate levels in our CABG patients using CPB

Cardiac Variables as Main Predictors of Endotracheal Reintubation Rate after Cardiac Surgery

Background: Reintubation in patients after cardiac surgery is associated with undesirable consequences. The purpose of the present study was to identify variables that could predict reintubation necessity in this group of patients. Methods: We performed a prospective study in 1000 consecutive adult patients undergoing cardiac surgery with cardiopulmonary bypass. The patients who required reintubation after extubation were compared with patients not requiring reintubation regarding demographic and preoperative clinical variables, including postoperative complications and in- hospital mortality. Results: Postoperatively, 26 (2.6%) of the 1000 patients studied required reintubation due to respiratory, cardiac, or neurological reasons. Advanced age and mainly cardiac variables were determined as univariate intra- and postoperative predictors of reintubation (all p values < 0.05). Multiple logistic regression analysis revealed lower preoperative (p = 0.014; OR = 3.00, 95%CI: 1.25 - 7.21), and postoperative ejection fraction (p = 0.001; OR = 11.10, 95%CI: 3.88 - 31.79), valvular disease (p = 0.043; OR = 1.84, 95%CI: 1.05 - 3.96), arrhythmia (p = 0.006; OR = 3.84, 95%CI: 1.47 - 10.03), and postoperative intra-aortic balloon pump requirement (p = 0.019; OR = 4.20, 95%CI: 1.26 - 14.00) as the independent predictors of reintubation. Conclusion: These findings reveal that cardiac variables are more common and significant predictors of reintubation after cardiac surgery in adult patients than are respiratory variables. The incidence of this complication, reintubation, is low, although it could result in significant postoperative morbidity and mortality

Relationship between gender and in-hospital morbidity and mortality after coronary artery bypass grafting surgery in an iranian population

Background: Many previous studies have investigated the influence of gender on coronary artery bypass grafting surgery (CABG) outcomes. Despite the great volume of reports on this issue, it is still not clear whether it is the gender of the patient or pre-existing comorbid conditions that is the best predictor for the different outcomes seen between men and women. Multiple studies have shown that women are at higher risk of postoperative complications than men, particularly in the perioperative period. Objectives: The goal of this study was to determine whether sex differences exist in preoperative variables between men and women, and to evaluate the effect of gender on short-term mortality and morbidity after CABG in an Iranian population. Patients and Methods: Data were collected prospectively from 690 consecutive patients (495 men and 195 women) who underwent isolated CABG. Preoperative, intraoperative, and postoperative variables, major complications and death were compared between the male and female patients until hospital discharge using multivariate analysis. Results: Women were older (P = 0.020), had more diabetes (P = 0.0001), more obesity (P = 0.010), a higher New York Heart Association functional class (P = 0.030), and there was less use of arterial grafts (P = 0.016). Men had more tobacco smokers (P = 0.0001) and lower preoperative ejection fractions (EF) (P = 0.030). After surgery, women had a higher incidence of respiratory complications (P = 0.003), higher creatine kinase (CK) – MB levels (P = 0.0001), and higher inotropic support requirements (P = 0.030). They also had a higher incidence of decreased postoperative EF versus preoperative values (P = 0.020). The length of ICU stay, incidence of return to ICU and postoperative death, were similar between men and women. Nevertheless, after adjusting for age and diabetes, female gender was still independently associated with higher morbidity in patients over 50 years of age. Conclusions: Women had more risk factors, comorbidities, and postoperative complications. Women older than 50 years of age were at a higher risk of postoperative complications than men. This difference decreased with younger age. In-hospital mortality rates were not influenced by sex, as there was no difference found between the two groups (2.5% women vs. 2.2% men; P > 0.05)

Comparison of bispectral index monitoring with the critical-care pain observation tool in the pain assessment of intubated adult patients after cardiac surgery

Background: Detecting pain is crucial in sedated and mechanically ventilated patients, as they are unable to communicate verbally. Objectives: This study aimed to compare Bispectral index (BIS) monitoring with the Critical-care pain observation tool (CPOT) and vital signs for pain assessment during painful procedures in intubated adult patients after cardiac surgery. Materials and Methods: Seventy consecutive patients who underwent cardiac surgery (coronary artery bypass graft or valvular surgery) were enrolled in the study. Pain evaluations were performed early after the operation in the intubated and sedated patients by using BIS and CPOT, and also checking the vital signs. The pain assessments were done at three different times: 1) baseline (immediately before any painful procedure, including tracheal suctioning or changing the patient�s position), 2) during any painful procedure, and 3) five minutes after the procedure (recovery time). Results: The mean values for CPOT, BIS, and mean arterial pressure (MAP) scores were significantly different at different times; they were increased during suctioning or changing position, and decreased five minutes after these procedures (CPOT: 3.98 � 1.65 versus 1.31 � 1.07, respectively (P � 0.0001); BIS: 84.94 � 10.52 versus 63.48 � 12.17, respectively (P � 0.0001); MAP: 92.88 � 15.37 versus 89.77 � 14.72, respectively (P = 0.003)). Change in heart rate (HR) was not significant over time (95.68 � 16.78 versus 93.61 � 16.56, respectively; P = 0.34). CPOT scores were significantly positively correlated with BIS at baseline, during painful stimulation, and at recovery time, but were not correlated with HR or MAP, except at baseline. BIS scores were significantly correlated with MAP but not with HR. Conclusions: It appears that BIS monitoring can be used for pain assessment along with the CPOT tool in intubated patients, and it is much more sensitive than monitoring of hemodynamic changes. BIS monitoring can be used more efficiently in intubated patients under deep sedation in the ICU. � 2016, Iranian Society of Regional Anesthesia and Pain Medicine (ISRAPM). All rights reserved

Impact of Body Mass Index on In-Hospital Mortality and Morbidity after Coronary Artery Bypass Grafting Surgery

Background: Obesity is a common risk factor for morbidity and mortality after cardiac surgery. However, the relationship between obesity and postoperative risk has not been fully defined. Methods: A prospective study of 1015 consecutive patients undergoing isolated coronary artery bypass grafting (CABG) was carried out. Body mass index (BMI) was used as the measure of obesity and was categorized as normal weight (BMI=20-25) and obese (BMI>25 and<35). The preoperative, operative, and postoperative risk factors as well as the complication and in-hospital death rates were compared between the two groups. Results: Of the 1015 patients, 40% had a normal weight and 49% were obese. Compared with the normal-weight group, the obese group had a significantly higher incidence of diabetes mellitus (P=0.007) and lower arterial partial pressure of oxygen (PaO2) (P=0.03). The normal-weight patients had a higher New York Heart Association (NYHA) Functional Class (P=0.03) and were at a higher risk for emergent surgery (P=0.003) or reoperation (P=0.002). Among the postoperative complications, respiratory complications (P=0.027) were more frequent in the obese patients. The duration of mechanical ventilation (P=0.001), the incidence of arrhythmia (P=0.011), low cardiac output syndrome (P=0.001), reintubation (P=0.001), and neurological complications (P=0.003) were significantly higher in the normal-weight patients. Obesity was associated with a lower risk of reoperation for bleeding (P=0.032). There were no significant differences in infective complications, length of intensive care unit (ICU) stay, total length of stay in hospital, and operative mortality between the groups. Conclusion: In the patients undergoing isolated CABG procedures, obesity did not increase the risk of operative mortality and morbidity with the exception of respiratory complications. The normal body weight patients were at a higher risk for complications than were the obese patients. Therefore, obese patients may safely undergo CABG without previous weight reduction if due attention is paid to minimize respiratory complications

Effect of various patient positions on endotracheal tube cuff pressure after adult cardiac surgery

Background: To avoid microaspiration or tracheal injury, the target endotracheal tube cuff pressure must be maintained 20–30 cmH2O. Changing in patients' positions may effect on endotracheal tube cuff pressure. The aim of this study was to investigate the effect of various patients' positions on endotracheal tube cuff pressure after adult cardiac surgery. Methods: This prospective, interventional study was conducted on 25 adult patients with orotracheal intubation for the cardiac surgery. Patients' endotracheal tube cuff pressure was assessed after surgery in a neutral starting position during an end-expiratory hold, and cuff pressure was regulated at 25 cmH2O. Then, ten changes in head position were performed: anteflexion, hyperextension, left and right lateral flexion, left and right rotation, semi-recumbent position (head elevation in 45°), recumbent position (head elevation in 10°), horizontal supine position, and finally, Trendelenburg position (10°). The observed cuff pressures were compared with the basic cuff pressure at the starting position. Results: Of total 250 measurements (25 participants in 10 positions), 109 (43/6%) were greater than the upper target limit of 30 cmH2O. In contrast, no measurements were less than the lower target limit of 20 cmH2O. 141 (56/4%) measurements were between the target limit of 20–30 cmH2O. All ten changes of patients' head position lead to statistically significant increase in endotracheal tube cuff pressure (P < 0.05). Conclusion: Simple changes in intubated patients' position could significantly increase in endotracheal tube cuff pressure that may potentially damage tracheal mucosa