Wells’ score for early prehospital screening of pulmonary embolism

Abstract

Pulmonary embolism (PE) represents a significant health problem due to nonspecific clinical features and a high risk of lethal outcome. PE diagnostics can sometimes be very difficult, especially at the prehospital level. We present a patient in whom early screening for PE at the prehospital level, performed using the Wells’ Score, was a life-saving event. Case scenario: the Emergency Medical Service (EMS) received a call regarding a male, aged 27 years, who was unconscious. Prior to losing consciousness, he complained of suffocation and tachycardia. Ten days earlier he sustained an injury to the knee which was immobilized with a splint, followed by bed rest. A year ago he was examined for chest pain, hypertension and tachycardia. On examination the patient was conscious, well oriented, eupneic, afebrile, with normal skin color. On pulmonary auscultation breath sounds were normal, and oxygen saturation was 90%. Findings on cardiac examination included: regular rate and rhythm, no murmur, blood pressure (BP) 120/85mmHg on both arms. ECG revealed sinus rhythm, rate of 100 beats/min, discreet signs of right heart strain (S1Q3T3 pattern), negative T wave from V1-V4, ST depression in D2, D3, AVF. A Wells’ score of 6 (most probably PE) was calculated: immobilization for 4 weeks - 1.5 points, tachycardia (pulse 120/ min) - 1.5 points and alternative diagnosis less probable than PE - 3 points. The patient was suspected of PE and referred to a cardiologist. Conclusion. Pulmonary embolism often remains undiagnosed during a patient’s lifetime or is erroneously diagnosed. The significance of the scoring of each patient aimed at the recognition of pulmonary embolism at the prehospital level cannot be underestimated.