Immunomodulatory Effects of Systematic 2-Hourly Repositioning on IL-6 and TNF-α in Non-Septic Mechanically Ventilated ICU Patients: A Single-Center Randomized Controlled Trial

Abstract

Background: Systemic inflammation contributes to morbidity in mechanically ventilated ICU patients, yet the immunomodulatory effects of routine nursing interventions such as repositioning remain poorly understood.

Objective: To evaluate systematic 2-hourly repositioning effects on serum IL-6 and TNF-α in non-septic mechanically ventilated patients.

Methods: Parallel-group RCT (n=60) following CONSORT guidelines. Experimental group received systematic repositioning every 2 hours; control received routine care (mean 4.6-hourly). IL-6 and TNF-α measured via blinded ELISA at days 1, 3, and 7. Linear mixed-effects models with Bonferroni correction (α=0.025).

Results: IL-6 decreased 31% in experimental group versus 11% in control; Cohen's d=1.19 (95% CI: 0.64-1.74). TNF-α: d=0.82 (95% CI: 0.29-1.35). Respiratory failure patients showed larger effects (d=1.42) than post-operative patients (d=0.78).

Conclusion: Systematic repositioning significantly reduces pro-inflammatory cytokines in non-septic patients. Findings require validation in larger, multicenter trials including septic populations and powered for clinical endpoints.