I just passed out!
As you begin lathering your hair and launch into the second verse of Calendar Girl the tones of your pager sound. Still shampoo’ed but now uniformed you dart out the door. Dispatch has a First Responder call for a 28-year old unconscious female. En route to the station you daydream about using an airway and bag valve mask on somebody other than a CPR dummy.
Your Engine’s code three arrival has drawn more people to the neighbouring lawns than you thought lived in this town. With jump kit and supplemental oxygen in hand you stumble onto the lawn. Just as your helmet slides over your eyes, yet again, you notice Mum standing calmly in the door. Wait, something is wrong here. Where is the arm waving? Where are the airport ramp “they’re in here” signals? Mum seems more concerned about her prized geraniums you just trampled on. Those and the size 12 top-soil prints you are trekking on her new carpet. Strange…
Once you enter the the living room it all becomes clear. Seated inside are a nervous boyfriend, Dad cursing the Jets for a missed field goal and a very embarrassed, though conscious, 28 year old female.
A Px who is currently unconscious is undergoing a life threatening emergency. A recently unconscious Px is a different story. You find your Px vitals all within range and other than intense blushing you discover no clinical findings. Yet this is no acid-reflux frequent flyer, Mum was right to summon your pre-hospital services. Your 28 year old Px has fainted (syncope). Although this Px is no longer in the load and go category they must still be transported to medical aid. During transport we can provide benefit above and beyond a secondary survey, supplemental O2 and, for once, a legible hand-off sheet.
So what is syncope? Syncope, as defined by the Merck manual, is a brief loss of consciousness followed by spontaneous return. There are also cases of near syncope which are defined as a near loss of consciousness preceded by a sense of impending unconsciousness, “I felt like I was going to faint” (ref: Merck Manual online). It is important to distinguish syncopal events from seizures. Although seizures involve altered LOCs, and some seizures present without tonic clonic muscle jerks, a true syncopal event commonly results from either inadequate cerebral blood flow or inadequate cerebral blood substrates (oxygen and/or glucose) (ref: Robert Porter, MD).
Hearing blood and brain together you may think stroke. This is not so, as evidenced by our now healthy 28-year old Px. The syncopal Px is usually not having a stroke due in part to their anatomy. As oxygenated blood departs the heart it passes through the aortic arch and into the two subclavian arteries. From each subclavian artery branches a vertebral artery and a common carotid artery. The carotid artery continues up beside the trachea (windpipe) and feeds the part of our brain that makes us not fish, a richly developed forebrain. The vertebral artery passes through the spinal column and up into the base of the brain to travel beside, and feed, the midbrain (ref: Chico, P, PhD). Our Px midbrain does not receive sufficient bloodflow and they become unconscious (and usually horizontal). Blood flow then returns and they immediately reawaken.
Depending on our level of training we may be able to provide the end physician with a few clinically relevant findings to begin figuring out why this Px has suffered a syncopal event. Are they hypoglycaemic? Hypotensive? Those of us trained in 12-lead EKG interpretation may discover a bradycardic arrhythmia whose effects the Px did not report feeling. Physicians attempting to diagnose the cause of a syncopal event are often limited in a history immediate to the event. Witnesses of the fainting may remain at the home or, as bystanders, continue on their way after the ambulance departs (ref: Robert Porter, MD).
There is quite a list of possible causes of syncope, the two most common though are vasovagal and idiopathic. In the latter category the Px is discharged with no clinical findings and will most probably suffer few, if any, syncopes in the future (ref: Robert Porter, MD). For the former category we should consider conditions that could limit cardiac output. For a complete listing check out this table. Although our full secondary will contain information necessary for the physician’s diagnosis there are more focused questions we can ask:
- Were you exercising? arguing? under acute emotional stress?
- What position were you in when you fainted?
- Do you remember feeling anything? Numbness or tingling in the fingertips or extremities?
- Most syncopal events are preceded by the feeling of impending unconsciousness, ask if they recall feeling this.
- Ask about certain conditions that could contribute to dehydration (vomiting, diarrhea).
- Syncope can sometimes be an early indicator of pregnancy, ask a female Px whether she is, or could be, pregnant.