IJCS | Volume 32, Nº1, January/ February 2019

29 Barbosa et al. Complications of CABG and hospital expenses Int J Cardiovasc Sci. 2019;32(1)28-34 Original Article Methods This is a single-center observational retrospective study. We selected 240 patients undergoing CABG at the National Institute of Cardiology (INC) in the period from 01 January to 31 December, 2013. We includedpatientsagedover30years, ofbothgenders, with coronary artery disease confirmed by coronary angiography and indication for surgical myocardial revascularization after evaluation by the medical staff, composed of a clinical cardiologist, a hemodynamicist and a cardiac surgeon. We excluded patients who had undergone surgical myocardial revascularization combined with other surgical procedures, such as valve surgeries and vascular surgeries. Hospitalization costs related tomedications, laboratory tests, complementary imaging tests, materials, healthcare professionals and other indirect costs, collected from patients’ medical records, were counted in accordance with the data provided by the cost centers. Indirect costs data were obtained from the Transparency Portal of the Brazilian Federal Government. Service agreements and expenses with security, food, information technology, contracting of general services, engineering companies, and maintenance of medical equipment were counted. The consolidated results allowed for the apportionment of the indirect costs per patient day. The costs with healthcare professionals were calculated according with the number of clinical doctors, surgeons, anesthetists, nurses, nursing technicians, physiotherapists, nutritionists and speech therapists who worked in the care of each patient. Subsequently, data related to the wages and workload of each professional were obtained from the Transparency Portal of the Brazilian Federal Government and, with this information, it was possible to estimate the value per hour worked by each professional involved in the healthcare of each patient, in each hospital sector where this patient remained hospitalized. We used the micro-costing method, in which the interventions performed on the patients are individually counted, finally leading to the total hospitalization costs. The values used as basis of cost estimation were obtained from the Table of Procedures and Medications of SUS Managing System (SIGTAP). Statistical analysis The statistical analysis of the continuous quantitative variables was carried out by the Student’s t-test, or the Mann-Whitney’s U test, to compare both samples, and the ANOVA test or the Kruskal-Wallis test to compare more than two samples. The results of these analyses were expressedasmedia and standarddeviation. The categorical variableswere assessedusing thequi-square test or the exact Fisher’s test. The results of the analysis of the categorical variables were expressed as percentage. The assessment of normality was performed using the Kolmogorov-Smirnov test, and the equality of the variances was assessed using the Levene’s test. An α value of 0.05 was determined. The analysis was performed using the IBM SPSS (Statistical Package for the Social Science) software (version 20.0.0). The research project was approved by the Ethics Committee in Research of the National Institute of Cardiology (approval number 648.089; CAAE: 30460013.4.0000.5257). The study was conducted in accordance with the principles of the Declaration of Helsinki. Results A total of 240 patients, 169 males and 71 females, who had undergone isolated myocardial revascularization at the National Institute of Cardiology, in 2013, were observed as shown in Table 1. Mean age was 61.7 years, 60.9 for men and 63.4 for women (p = 0.054). Twenty-four patients were over 75 years of age (10.0%). The mean time of hospital stay was 32.3 days with standard deviation of 22.7 days. The patients waited, on average, 14.2 days for the surgery, with standarddeviation of 8.4. The average recovery period after surgery was 18.4 days, with standard deviation of 20.9 days. In total, 97 patients incurred complications of some type during hospitalization, corresponding to 40.4% of patients. Complications were grouped into categories related to infectious complications, cardiovascular complications, arrhythmia, bleeding and others, which could not be classified in the other groups, as shown in Table 2. Direct costs were analyzed by the micro-costing approach and organized into groups relating to medications, laboratory and complementary imaging tests, material and professional costs. Table 3 shows the average costs per intervention category during hospitalization, and the next sections will demonstrate the costs per category.