To approach the effect of different vasopressor on hemodynamics, volume responsiveness, fluid volume balance, renal function and prognosis in patients with acute respiratory distress syndrome (ARDS) complicated with septic shock.

A prospective single-blind randomized controlled trial was conducted. ARDS patients with septic shock admitted to the Department of Critical Care Medicine of Jiangxi Provincial People's Hospital from January 1st, 2015 to May 1st, 2016 were enrolled. The patients satisfied ARDS Berlin diagnostic criteria, over 15 years old, needing vasopressor after fluid resuscitation were enrolled. The patients were divided into norepinephrine group (NE group) and terlipressin group (TP group) by randomise number table derived by computer. Patients in TP group were given terlipressin (0.01-0.04 U/min) with an intravenous pump, while those of NE group were given norepinephrine (> 1 μg/min) with an intravenous pump, and the target mean arterial pressure (MAP) was maintained at 65-75 mmHg (1 mmHg = 0.133 kPa). Hemodynamics and extravascular lung water index (EVLWI) were monitored by pulse indicator continuous cardiac output (PiCCO). The volume responsiveness of patient was evaluated by passive leg raising (PLR) test, and cardiac index (CI) change (ΔCI ≥ 10%) served as positive volume responsiveness. The differences in hemodynamics, EVLWI, oxygenation index (OI), lactate clearance rate (LCR), rate of positive volume responsiveness, urinary output, fluid volume balance, renal function, and prognostic indicators were compared between the two groups.

Fifty-seven patients with ARDS complicated with septic shock were enrolled, with 26 patients in NE group, and 31 patients in TP group, the baseline data in both groups was balanced with comparability. Compare with NE group, 48-hour and 72-hour heart rate (HR) in TP group was significantly slowed (bpm: 82.1±6.8 vs. 87.6±7.4, 81.3±6.1 vs. 85.6±8.3, both P < 0.05), 72-hour central venous pressure (CVP) was significantly decreased (mmHg: 9.4±2.6 vs. 10.9±3.0, P < 0.05), but no significant difference was found in HR, MAP, CVP, CI, EVLWI, OI and LCR at other time points between the two groups. 48-hour and 72-hour positive volume responsiveness rate in TP group were significantly increased as compared with those of NE group (74.2% vs. 46.2%, 64.5% vs. 38.5%, both P < 0.05), urinary output on the 2nd day (mL/24 h: 2 342.8±704.1 vs. 1 944.6±684.3) and fluid volume balance (mL: -319.7±54.8 vs. -169.6±27.2) were significantly decreased (both P < 0.05). There was no significant difference in positive volume responsiveness rate, urine output, fluid volume balance, and the level of serum creatinine at other time points between the two groups. There was no statistically significant difference in the following features between TP group and NE group: duration of mechanical ventilation (days: 8.41±2.97 vs. 9.67±3.56), length of intensive care unit (ICU) stay (days: 12.84±4.47 vs. 14.77±5.01), total length of hospital stay (days: 19.34±7.37 vs. 21.07±8.41), and 28-day mortality (29.0% vs. 30.8%, all P > 0.05).

Compared with norepinephrine, terlipressin for ARDS patients with septic shock is more conducive to restrict fluid load, improve the renal perfusion and increase urine output. However, in both groups there was no significant difference in the efficiency of stabilizing hemodynamics, shortening the duration of mechanical ventilation, reducing ICU or hospital days and decreasing 28-day mortality.

Acute respiratory distress syndrome; Septic shock; Terlipressin; Norepinephrine; Volume responsiveness