Traumatic Full Arrest

24-year-old male presents via EMS after being involved in altercation. According to bystanders, patient was noted to sustain several gunshot wounds from close range, notably to the left anterior chest and left upper extremity. On EMS arrival, patient was diaphoretic but awake, with GCS of 15, heart rate 140 bpm, blood pressure 95/60 mmHg, respiratory rate 26 with room air oxygen saturation of 90%. On arrival in the ED, patient becomes initially combative, then develops altered mental status. Examination now reveals no palpable pulses or measurable blood pressure.