Evaluation and control of correction of volemic status using estimated continuous cardiac output technology for elective hernioplasty in obese patients

Abstract

The objective. To substantiate the use of the Estimated Continuous Cardiac Output technology for the assessment and correction of the volemic status in obese patients during routine hernia repair of the anterior abdominal wall under spinal anesthesia. Subjects and methods. The study included 40 patients who underwent hernia repair of the anterior abdominal wall under spinal anesthesia. Inclusion criteria: body mass index of more than 30–40 kg/m2, physical status according to ASA II or III, no history of indications of diabetes mellitus, myocardial infarction, stroke, malignant neoplasm. Exclusion criteria: refusal of the patient, contraindications to spinal anesthesia. The patients were randomly divided into 2 groups of 20 people. Patients of both groups were comparable in age, gender, and physical status. Group 1 patients underwent preoperative evaluation, as well as monitoring of the effectiveness of correction of volemic status using EsCCO technology. Intraoperative infusion therapy was prescribed to patients of group 2 based on the doctor’s experience, blood pressure, heart rate and formulas for calculating the infusion load. Statistical analysis of the data obtained was performed using MS Excel, Statistica 10. To test the hypothesis of the normality of the distribution of a random variable, the Shapiro-Wilk test was used. Under conditions of normal distribution of quantitative indicators, descriptive statistics were used for statistical data analysis: mean value (M); standard deviation (SD); 95% confidence interval of standard deviation (C1). The Student’s t-test was used to analyze the differences between quantitative characteristics. The differences were considered significant at p<0.05. Results. The greatest decrease in systolic blood pressure by 4 minutes (from 122.8 to 117.5 mm Hg, by 4.3%) was revealed among group 1A patients, by 2 minutes (from 120.6 to 115.4 mm Hg, by 4.3%) among group 2 patients by 4 minutes (from 123.4 to 107.2 mm Hg, by 13.1%) from spinal anesthesia. The most pronounced change in heart rate relative to baseline data among group 1A and group 1B patients was noted at 2 minutes after intrathecal administration of bupivacaine (from 72.4 to 76.2, by 5% and from 74.6 to 78.4, by 4.8%, respectively) with a gradual return to parameters that are close to the baseline, and among patients in group 2, a sharp jump in heart rate from 73.8 to 83.3 (by 11.4%) was noted at 2 minutes. Heart rate continued to increase and by 6 minutes reached an average of 86.0, which is 14% higher than the original value. In all three groups of the study, the greatest deviation from the baseline was found at 6 minutes after the administration of bupivacaine with a further gradual return to slightly larger parameters than the base[1]line. Significant changes in SI were detected at 6 minutes from the execution of the neuroaxial block among all patients of this study. For group 1A, they ranged from 3.89 to 5.25 l/min/m2 (by 27.6%), for group 1B patients from 3.88 to 5.1 l/min/m2 (by 23.9%) and for group 2 from 3.84 to 5.45 l/min/m2 (by 29.5%). Conclusion. The Estimated Continuous Cardiac Output technology can be effectively used to assess and correct the volemic status in obese patients when performing elective hernia repair of the anterior abdominal wall under spinal anesthesia.