Abstract:Objective: To evaluate the variability index of internal jugular vena cava (VJVC) and variability index of inferior vena cava (VIVC) through ultrasound in predicting fluid responsiveness in adult petients with cardiosurgery. Methods: Prospectively, 76 adult pa tients who had cardiosurgery in the Department of Cardiovascular Surgery, Chongqing General Hospital were collected in the study, and the passive leg raising (PLR) tests were carried out on them of intensive monitoring in the intensive care unit (ICU) ward. Patients with elevated cardiac output index≥10% after PLR were included in the fluid responders (FR) group, while patients with elevated cardiac output index<10% were included in the fluid unresponders (FN) group. Meanwhile, the hemodynamic parameters of heart rate, systolic blood pressure, diastolic blood pressure and mean blood pressure were all recorded before and after PLR tests in both groups. The N-terminal pro-brain natriuretic peptide (NT-proBNP), VJVC, and VIVC were recorded before PLR tests. Results: After PLR tests, in FR group, there were no significant differences in central venous pressure［ (7.6±1.9) mmHg vs. (10.1±11.4) mmHg, P=0.154］; there were significant differences in heart rate［ (83.0±8.9) bpm vs. (75.3±7.5) bpm, P=0.000］, systolic blood pressure［ (91.1±9.4) mmHg vs. (94.9±9.1) mmHg, P=0.000］, diastolic blood pressure［ (52.8±9.8) mmHg vs. (58.9±8.2) mmHg, P=0.000］, and mean blood pressure［ (65.6±9.2) mmHg vs. (70.7±8.0) mmHg, P=0.000］. In FN group after PLR, there were no significant differences in systolic blood pressure［ (90.0±7.4) mmHg vs. (92.3±6.7) mmHg, P=0.076］, and there were significant differences in heart rate［ (83.5±9.1) bpm vs. (80.7±7.4) bpm, P=0.005］, diastolic blood pressure［ (50.0±7.1) mmHg vs. (55.2±5.7) mmHg, P=0.000］, mean blood pressure［ (63.3±6.8) mmHg vs. (67.6±5.0) mmHg, P=0.000］, and central venous pressure［ (7.9±1.6) mmHg vs. (10.2±1.4) mmHg, P=0.000］. There were no significant differences in heart rate, systolic blood pressure, diastolic blood pressure, mean blood pressure and central venous pressure between FR goup and FN group before PLR tests. After PLR, there were no significant differences in systolic pressure［ (94.9±9.1) mmHg vs. (92.3±6.7) mmHg, P=0.075］and central venous pressure［ (10.1±11.4) mmHg vs. (10.2±1.4) mmHg, P=0.474］between the two groups, and there were significant differences in heart rate［ (75.3±7.5) bpm vs. (80.7±7.4) bpm, P=0.001］, diastolic blood pressure［ (58.9±8.2) mmHg vs. (55.2±5.7) mmHg, P=0.014］, and mean blood pressure［ (70.7±8.0) mmHg vs. (67.6±5.0) mmHg, P=0.024］. In addition, There was no significant difference in plasma NT-proBNP between the two groups［ (1 144.6±992.1) pg/mL vs. (1 243.6±1095.0) pg/mL, P=0.335］, and there were significant differences in VIVC［ (15.2±3.9) % vs. (12.5±4.2) %, P=0.003］and VJVC［ (17.7±4.3) % vs. (13.9±4.0) %, P=0.000］. The cutoff value of VIVC diagnostic capacity was 11.5%, the sensitivity was 87.8%, and the specificity was 55% (AUC=0.7, 95% CI=0.575-0.826, P=0.003) . The cutoff value of VJVC diagnostic capacity was 15.5%, the sensitivity was 68.3%, and the specificity was 77.1% (AUC=0.764, 95% CI=0.654-0.874, P=0.000) . Conclusion: VIVC and VJVC can easily predict the noninvasive parameter of fuid responsiveness in patients with cardiosurgery and accurately guide the clinical rehydration therapy. Moreover, the internal jugular vein is easier to measure than the inferior vena cava, its position is shallower and more constant, and it is not affected by the obesity of patients, abdominal pressure and drainage tube after cardiosurgery, so the repeatability is better. It is more recommended to use the VJVC to evaluate the fluid responsiveness after cardiosurgery in clinical work.
