Comparison of Different Hemodynamic Items in The Prediction of Fluid Responsiveness in Hypotensive Trauma Patients Under Mechanical Ventilation

This study aimed to compare pulse pressure and pulse oximetry fluctuations in predicting the response to fluid therapy and find a noninvasive method to monitor intravascular volume in traumatic patients on ventilators.
Forty hypotensive severe multiple trauma patients under mechanical ventilation were enrolled in this cross-sectional study. Based on cardiac index (CI) changes in response to 500-mL normal saline administration, patients were divided into two groups of responders and non-responders (each with 20 subjects). Mean arterial pressure (MAP), diastolic blood pressure (DBP), systolic blood pressure (SBP), heart rate (HR), pulse pressure variation (PPV), and respiratory variations in pulse oximetry plethysmographic waveform amplitude (ΔPOP) were compared before and after the intervention.
The mean age of patients (22 males and 18 females) was 44.8 ± 15.4 years, who were divided into two groups: responder and non-responder to liquid. Following fluid therapy, SBP, DBP, and MAP only significantly increased in the responder group, while PPV and ΔPOP significantly decreased (P < 0.05). Also, PPV and ΔPOP significantly correlated before and after the intervention in the study groups (P < 0.05).
This study demonstrated that ΔPOP, as PPV monitoring, can predict fluid responsiveness and volume status in hypotensive multiple trauma patients under controlled mechanical ventilation.