[Clinical study of fluid resuscitation guided by peripheral perfusion index in patients with septic shock]

To explore the guiding effect of peripheral perfusion index (PI) on fluid resuscitation in patients with septic shock.

Sixty-five patients with septic shock who were diagnosed according to relevant criteria of septic shock and admitted to the department of critical care medicine of the Affiliated Hospital of Hangzhou Normal University from September 2017 to December 2020 were included. Patients were divided into the conventional treatment group (30 cases) and PI guidance group (35 cases) by random number method. Both groups of patients were treated with the bundle according to clinical guidelines. Sputum, urine and blood were collected for pathogenic microorganism culture before the application of antibiotics, and vasoactive drugs were given. Both groups need to achieve all the following resuscitation goals within 6 hours: urine output > 0.5 mL×kg^-1×h^-1, mean arterial pressure (MAP) ≥ 65 mmHg (1 mmHg ≈ 0.133 kPa), central venous pressure (CVP) was 8-12 mmHg, and central venous oxygen saturation (ScvO₂) ≥ 0.70. There was no further resuscitation in the conventional treatment group after the goals were achieved. In addition to these four goals, the PI guidance group was expected to achieve PI ≥ 1.4. Heart rate (HR), CVP, MAP, ScvO₂, blood lactic acid (Lac), the time of fluid negative balance, intensive care unit (ICU) mortality and 28-day mortality between the two groups were compared before and after 6 hours of fluid resuscitation.

Before fluid resuscitation, there were no statistically significant differences in all indicators between two groups. After 6 hours fluid resuscitation, the four treatment goals in PI guidance group were slightly lower than those of the conventional treatment group [HR (times/min): 96.5±12.1 vs. 97.7±7.9, MAP (mmHg): 83.2±6.2 vs. 82.1±7.5, ScvO₂: 0.661±0.077 vs. 0.649±0.051, CVP (mmHg): 10.8±2.7 vs. 10.4±2.1], there were no statistically significant differences between the two groups (all P > 0.05); the Lac level of the PI guidance group after resuscitation was lower than that of the conventional treatment group, and the difference was statistically significant (mmol/L: 4.8±1.3 vs. 5.9±1.4, P < 0.05); the duration of fluid negative balance in the PI guidance group was earlier than that in the conventional treatment group [days: 3.0 (2.0, 3.0) vs. 3.5 (3.0, 4.0), P < 0.05]. The ICU mortality and 28-day mortality in the PI guidance group were lower than those in the conventional treatment group [ICU mortality rate: 37.1% (13/35) vs. 50.0% (15/30), 28-day mortality rate: 57.1% (20/35) vs. 60.0% (18/30)], but the differences were not statistically significant (both P > 0.05).

The peripheral PI can be used as an important indicator of fluid resuscitation in patients with septic shock. PI guiding fluid resuscitation in patients with septic shock can reduce Lac levels, shorten the duration of fluid negative balance and reduce the risk of fluid overload.