Perfusion index: could it be a new tool for early identification of pulmonary embolism severity?

Perfusion index (PI) is a promising indicator for monitoring peripheral perfusion. The present study aimed to compare the efficiency of PI and PESI score in estimating the 30-day mortality and treatment needs of patients diagnosed with pulmonary embolism in the emergency department. This study was prospective and observational. The demographic features of the patients, comorbidities, vital signs, PESI score, PI, treatment applied to the patient and airway management, right ventricular diameter/left ventricular diameter ratio, length of hospital stay, outcome, and 30-day mortality were recorded. A total of 94 patients were included. All patients' vital signs and PI values were recorded on admission. The mean pulse rate (p = 0.001) and shock index (p = 0.017) values of deceased patients were statistically significantly higher, while the mean PI (p = 0.034) was statistically significantly lower. PESI score and PI were statistically significant to predict the need for mechanical ventilation (PI, p = 0.004; PESI score, p < 0.001), inotropic treatment (PI, p = 0.047; PESI score p = 0.005), and thrombolytic therapy (PI, p = 0.035; PESI score p = 0.003). According to the ROC curve, the mortality prediction power of both PESI (AUC: 0.787, 95% CI 0.688-0.886, cutoff: 109.5, p < 0.001) and PI index (AUC: 0.668, 95% CI 0.543-0.793, cutoff: 1, p = 0.011) were determined as statistically significant. PI might be helpful in clinical practice as a tool that can be applied to predict mortality and treatment needs in PE.