DWK Fraser, CD, BA, PCP @DWKF
Views are my own, and do not represent my employers in any way.
I recently attended to a retired gentleman who had been picking up some work around the holidays. He’d been an electrician for 25 years, and had retired the year before. When his first grandchild was on the way right before Christmas he decided to pick up some work to get his daughter and son-in-law something special, and to help set up the nursery for them.
He fell off a 12 foot ladder, and suffered a basal skull and sinus fracture, along with an obviously displaced fracture of his arm. He was briefly unconscious and had some aspiration before we got there, but was awake and alert upon initial exam with a chief complaint of arm pain and a headache. His teeth were intact, he had no Battle’s sign or Raccoon Eyes, no epistaxis or discharge.
He “usually” took pills for his blood pressure, his angina, his afib, and a few others which he also couldn’t name, but he knew it was important to tell people he was on blood thinners. He was mildly tachycardic and normotensive. He didn’t look unwell.
How can you predict the degree of injury in this patient? He’s medicated in such a way that his body’s response is blunted. He’s at risk of increased ICP and Cushing’s, and of bleeding in general, but how to judge his vital signs?
There’s a great tool which allows you to predict otherwise difficult to detect shock states, the Shock Index. There’s evidence to back it up in helping to differentiate major from minor injuries, and it’s even validated for use in geriatric patients, even when neither HR and SBP were useful on their own.
SI = HR / SBP. The faster the heart rate the greater the degree of compensation, and the BP is indicating how well the body is achieving perfusion. A normal range is 0.5-0.75 ( HR60 BPM / 120SBP = SI of 0.5, HR90 / 120SBP = SI 0.75, HR 120 / 120SBP = SI 1).
A Shock Index greater than 0.9 should be assumed to be actively bleeding!