‘Freezing‘ time to save lives – a groundbreaking treatment or a risky gamble, asks Serene Dhawan
From the enchanted slumbers of Sleeping Beauty and Snow White to the cryogenic chambers of Prometheus and Passengers, we have long been fascinated by the concept of suspended animation. Now, in a ground-breaking clinical trial at the University of Maryland Medical Centre, doctors are using this fantastical technique as an experimental therapy for patients who have suffered acute trauma, such as a stab wound or gunshot. Given the nature of their injuries, these individuals must be operated on within a limited time window, often just a few minutes. By directly injecting ice-cold saline solution into the heart or a major artery, a patient’s body can be rapidly cooled to ~10°C, thus halting metabolic activity and buying doctors up to two precious hours to repair the damage. Post-surgery, the patient is warmed up using a machine that mechanically circulates and oxygenates their blood. Whilst this technique, formally known as emergency preservation and resuscitation (EPR), could revolutionise the treatment of severe trauma, key challenges remain unsolved. The long-term physiological consequences of prolonged oxygen deprivation, as a result of cryogenic stasis, are unclear, as is the likelihood of reperfusion injury and multi-organ failure once a patient is “defrosted”. Current efforts are underway to develop drugs which can minimise potential detrimental side-effects and extend the period of time for which an individual can be suspended. Their efficacy, as well as the therapeutic value of EPR, will be revealed in a forthcoming publication from the team in Maryland in 2020.