Vasovagal Response

COMMON NAMES

Vasovagal syncope, vasovagal attack, neurocardiogenic syncope, and reflex syncope are used interchangeably for the same event. Presyncope describes the same drop in heart rate and blood pressure without quite reaching full loss of consciousness, the warning stage rather than a separate condition. Fainting is the plain-language version of all of these.

WHAT TO LOOK FOR

The reflex itself isn't dangerous, the real risk is what happens on the way down: a fall from standing, kneeling, or suspension, hitting furniture or the floor, or a rope or collar position that turns a simple faint into something worse.

Warning signs arrive before consciousness goes, often starting with wet palms before anything else is noticeable, followed by a sudden, distinct wave of heat. Lightheadedness, nausea, ringing ears, tunnel vision, and colour draining from the face tend to follow.

WHAT IT SEPARATES FROM

Cardiac syncope: the two get confused because both are fainting, but a cardiac cause is a medical emergency and a vasovagal one usually isn't. Vasovagal syncope has a trigger, builds up warning signs first, and happens while upright, gravity is part of the mechanism. Cardiac syncope drops someone suddenly with no trigger or warning, can happen during exertion or lying down, and often causes injury from the fall. Any of those, no trigger, no warning, exertion, lying down, means medical evaluation, not a rest and a glass of water.

WHAT TO DO

Any of the warning signs above means acting immediately, not waiting to see if it passes, even if they still seem alert and able to stand, that can change within seconds. Don't assume they can lower themselves down under their own control: with the world spinning, a controlled descent isn't really possible for them, and expecting it is how people get dropped. Cut rope or restraints free if that's what's stopping them getting down safely, and be ready to catch and support full weight on the way down, they may go fully limp partway through, not just need steadying. Once down, remove or loosen anything around the neck, a collar or choker, then get them lying on their back with legs raised about 30cm, and check they're breathing and have a pulse. Acting at the warning stage usually stops it from progressing to a full faint.

If they're not breathing, start CPR immediately. If they are breathing but haven't come around within one minute, that's the point to call emergency services rather than keep waiting.

Let them come up in their own time rather than rushing to standing: the body needs time to adjust back to gravity, and standing straight up before it has risks a second drop right back down. From lying flat, going to hands and knees with the head dropped forward first, then rolling up slowly, gives blood pressure a chance to catch up gradually instead of all at once.

Positioning removes most of the fall risk before it's needed: running a scene known to trigger this seated or kneeling rather than standing means there's nowhere to drop from. Tensing the large muscles of the legs and core for a few seconds, releasing, and repeating sometimes raises blood pressure enough to pull back from the edge before it goes further, it's not a reliable abort button, just worth trying if there's a moment to.

A general safeword like red is urgent, but it doesn't say what's actually happening, it could mean anything from stop to something hurts, not specifically I'm about to go down, catch me. A phrase agreed on in advance for this exact moment, something like 'I'm going down', tells a partner what's actually happening, but only if it's established before it's needed, there's no time to explain once the warning signs have started.

If fainting happens to you regularly, say so ahead of time too. It looks sudden and dramatic to anyone watching, and coming around to a crowd shoving water at you and offering to call an ambulance is disorienting on its own, it also pulls your partner's attention into managing everyone else's alarm instead of just being with you. Anyone not directly helping should give space, not gather, and let your partner take the lead on what you actually need.