Passive Leg Raising Effect at Resuscitation Among Patients With Vasoplegic State

Background: Several dynamic parameters have been used clinically to predict volume responsiveness and to guide fluid administration of which passive leg raising (PLR) is one of the most reliable techniques. PLR induces rising in cardiac output attributes through an unstressed volume mobilization from legs to heart causing autologous preload increment. Appropriate fluid resuscitation is essential and can be optimized by hemodynamic-based approach to vasodilatory hypotension. Objective: This study aimed to evaluate the effectiveness and safety of PLR at early resuscitation among patients with vasoplegia. Methods: We conducted a comparison study concerning an experimental design using a single blinded assessment of the outcomes that assigned patients with shock to be treated with PLR or flat position at early resuscitation. Forty patients with shock were included in this study. Twenty patients performed PLR at early resuscitation compared with the others that performed in the flat position and were measured for cardiac output (CO), mean arterial pressure (MAP), diastolic blood pressure (DBP), heart rate (HR), central venous pressure (CVP) and systemic vascular resistance (SVR) immediately after the procedures. The primary outcome was to evaluate the effect of early PLR on hemodynamic variables among hypotensive patients by comparing the difference in CO while the secondary outcomes were differences in MAP, DBP, HR, CVP, SVR, survival at hospital admission and the pulmonary complications of chest x-rays between the two groups. Results: No difference was observed in baseline characteristics between the two groups of patients. Compared with the flat position, PLR at early resuscitation significantly increased CO (3.57 ± 0.27 vs. 2.2 ± 0.18 L/min, p = 0.037), MAP (22.48 ± 5.6 vs. 10.83 ± 4 mmHg, p<0.001), DBP (19 ± 0.20 vs. 1.23 ± 0.12 mmHg, p=0.001) and CVP (4.52 ± 0.19 vs. 2.18 ± 0.13 mmHg, p=0.002). However, no differences were observed in HR, SVR, pulmonary complications of chest X-rays [2 (10%) vs. 1 (5%), p = 0.23] as well as survival at hospital admission [16 (80%) vs. 13 (65%), p = 0.48] between the two groups. Conclusion: Among patients with shock, PLR at early resuscitation significantly increased CO, MAP, DBP and CVP than that of those performing the flat position. No differences were found in HR, SVR, pulmonary complications; PLR did not improve survival to hospital admission.