Socio-demographic and clinical characteristics
A total of 1149 patients who underwent cardiopulmonary bypass surgery at Cardiac Center Ethiopia from these 326 samples were systematically selected. Two hundred ninety-seven were complete charts, 23 were incomplete and replaced by other charts. Finally, we reviewed 320 complete patient charts for this study. It gives the response rate (the completeness rate of 98.1%). Their mean age was [23.5 ± 14.8] years, and 188 were females (58.8%). Inotrope and Vasopressor Support Ventricular and vascular dysfunction are pervasive post-cardiac surgery, and most patients need inotropic or vasopressor support after separation from bypass. In this study, nearly two-thirds of 195(60.9%) of the study participants supported inotropes or vasopressors. (Table1).
The immediate postoperative period of most cardiac surgery is correlated with hemodynamic liabilities and un-stabilities which are typical early postoperative complications. Monitoring those hemodynamic measuring parameters in the entire course is crucial for predicting patient outcomes and prognosis. In this study, the study subjects' hemodynamic status data shown as follows. Above half of the study, subjects used the Del-Nido cardioplegia 189 (53.4%) and 180 (56.2%) patients Glucose level was 126-200. (Table 2)
Different types of cardiac surgeries will be selected and applied based on the patient's disease condition, types of illness, age, and presence of comorbidities. In this study, three types of operative categories underwent. Valve replacement accounts for 189(59.1%), congenital heart disease surgery 104(32.5%). (Figure 1)
During open-heart surgeries, intersecting the blood flow through the aorta by applying a cross-clamp is often an essential step to permit surgical repair. The mean cross-clamp time for the study subjects is 84 ±46.9 minutes. An extended period of cross-clamp time commonly a risk factor for significant postoperative morbidity and mortality. In this study, <60 minutes in 115 patients 35.9%, 60-90 minutes in 89 patients 27.8%, and > 90 minutes in 116 patients 36.3%. A significantly increased cross-clamp time is a predictor of mortality, increased need for inotropes, prolonged intensive care unit stay, and complex adverse outcomes (Figure 2)
The magnitude and Adverse outcomes of Hyperlactatemia
This study assessed the magnitude of hyperlactatemia showed a higher prevalence of 37.5% (95 CI 27.1- 48.9.1). The outcome after any heart surgery is determined by the patient's pre-existing symptoms and intraoperative factors. These various factors contribute to the development of hyperlactatemia and the effect of undesirable postoperative outcomes for patients. In this study, hyperlactatemia adversely affects patient outcomes and prognosis. ICU stay adversely affected by a rise in lactate level. Patients with elevated lactate stay in ICU longer durations when compared with those with low lactate level [(74 % versus 47%), P=0.000]. Besides, patients with elevated lactate levels also need more ionotropic drug use when compared with their counterparts [(66.6 % versus 57.7%), P=0.000). Likewise, lactatemia increases the duration of intubation than those who had average lactate level [(85% versus 47%), P=0.000). (Table 3)
Associated factors of hyperlactatemia among patients who underwent cardiopulmonary bypass surgery
A logistic regression model was used to evaluate the independent predictor's hyperlactatemia. First, a bi-variable logistic regression model was done to screen potential candidate variables for multivariable logistic regression. Variables with a P-value of < 0.25 were included in a multivariable logistic regression model. After conducting bivariate analysis, variables like age, sex, systolic BP, diastolic BP, glucose level, Hemoglobin level, Heparin, Atrial fibrillation, anti-platelet drugs, and operative category entered to multivariable analysis for further analysis.
Variables having a statistically significant association in multivariable logistic regression were older age and female gender with hyperlactatemia.
The odds of hyperlactatemia among patients who underwent cardiopulmonary bypass surgery patients age > 40 years were 6.8 times higher compared with those ≤ 50years of age [AOR: 6.8 (95% CI 1.7-25), P=<0.008]. Similarly, the odds of developing hyperlactatemia among female patients who underwent cardiopulmonary bypass surgery is 1.8 times higher when compared with their counterparts [AOR: 1.9 (95% CI 1.1-3.8), P=0.048]. (Table 4)