There are a few magic lo-tech treatments about. There’s the precordial thump, but there’s also the self administered cough CPR. Documented in several case series from the cath labs of the 70s and 80s, coughing every 1-3 seconds was shown to keep patients alive and conscious despite VF cardiac arrest, for up to 39 seconds.
How it works
Coughting is done by closing the glottis and rapidly increasing the intrathoracic pressure before opening the glottis and releasing the pressure by forcefully expelling air. This rapid rise in intrathoracic pressure also affects the heart (and large vessels in the thorax). A patent aortic valve and intact periferal vascular tone means the pressure stays high(er) in the aorta than in the heart when the cough is released.
These cases are from the cath lab – a perfect place to observe and monitor cases like these.The arterial pressure wave resulting from a cough exceeded that induced by external chest compression on the same patients. Blood pressure is not flow, and in these studies they did not measure cardiac output, but the sustained consciousness for up to 39 seconds is good evidence that the cough and pressure rise also resulted in forward flow of blood.
Three images from cough CPR.
Cough CPR and external/regular CPR on the lower graphs, ECG trace on top graphs.
The limitations are obvious, very few people realise they are having a fatal ventricular arrythmia or sudden asystole. And very few around them would realise quickly enough to get them to start coughing violentely with regular intervals. The only place it could be practical is probably in VT fast enough to make the patient severely hypotensive, but not unconscious (yet), coughing might keep them afloat until other measures are in place. Also, as in the article, patients can be instructed in a cath lab during settings where cardiac arrest is not unlikely.
Despite these cough-CPR unpracticalities, I find it very interesting and highly amusing that a person in cardiac arrest can keep himself alive through simple coughing.