Pre-ROSC Intra-Nasal Cooling Effectiveness (PRINCE)

The purpose of the study was to demonstrate the safety and feasibility of early intranasal cooling prior to return of spontaneous circulation (ROSC) in the emergency medical services (EMS) environment. It was hypothesized that cooling during the resuscitation attempt would increase ROSC and subsequent survival. The study was not powered to demonstrate statistically-significant differences in any outcome parameter, but was intended as an exploratory study only.

Out of hospital cardiac arrest remains a significant cause of death. Mild hypothermia induced after resuscitation from cardiac arrest has been shown to improve neurologically intact survival. Studies in dogs and rodents have demonstrated improved outcomes when cooling is initiated intra-arrest. The RhinoChill is a non-invasive cooling device through which rapid cooling is achieved via the intranasal delivery of an evaporative coolant into the nasopharynx. Due to its non-invasive and portable nature, the RhinoChill can be used to begin cooling earlier than other cooling devices. Studies performed using the RhinoChill in a porcine model of cardiac arrest suggest that cooling with the RhinoChill prior to the first defibrillation attempt facilitates resuscitation and improves resuscitation rate and neurologically intact survival. This study is being performed to assess the feasibility of using the RhinoChill device in the pre-hospital setting to improve resuscitation from cardiac arrest.

Advanced cardiac life support according to American Heart Association & European Resuscitation Council 2005 Guidelines

ROSC was defined as the return of an organized rhythm on electrocardiography (ECG) with a palpable pulse that was maintained for at least 20 minutes.

The study end-point was hospital discharge. This outcome measure is the patient count for those that were discharged alive from the hospital.

The Cerebral Performance Categories (CPC) are used to describe neurological outcome. A CPC of 1 or 2 is considered "neurologically intact." - Good cerebral performance: little to no deficit. - Moderate cerebral disability: capable of independent activities of daily life - Severe cerebral disability: conscious, but dependent on others for daily support - Coma or vegetative state - Death or brain death

The therapeutic temperature range for treatment in cardiac arrest is considered to be 32-34C. Time to therapeutic temperature was taken as the first time in which 34C was measured. Tympanic and core temperatures were taken in all patients.

Length of stay data for patients admitted to the hospital will be calculated for: Days on ventilator Days in intensive care without ventilator Days in general ward

These were defined serious adverse events that are not direct sequelae of the cardiac arrest itself or the underlying cardiac disease. Therefore, these do not include recurrent arrests occcuring within 24 hours of resuscitation nor deaths due to lack of cardiac and/or neurological recovery.

These were all non-serious adverse events that occurred between the time of enrollment and 24 hours after resuscitation. These did not include a failure to achieve ROSC.

Inclusion Criteria: ≥18 years Collapse was witnessed No pulse Unresponsive to external stimuli Exclusion Criteria: Have an etiology of cardiac arrest due to trauma, severe bleeding, drug overdose (OD), cerebrovascular accident (CVA), drowning, smoke inhalation, electrocution, hanging Already hypothermic Head trauma Cannot place intra nasal catheters Do Not Attempt to Resuscitate (DNAR) orders Known or clinically apparent pregnancy Have a known coagulopathy (except therapeutically induced) Are known to have a need for supplemental oxygen Achieve return of spontaneous circulation (ROSC) prior to initiating cooling Are reached by emergency medical services (EMS) personnel more than 20 minutes after collapse

Tsai MS, Barbut D, Tang W, Wang H, Guan J, Wang T, Sun S, Inderbitzen B, Weil MH. Rapid head cooling initiated coincident with cardiopulmonary resuscitation improves success of defibrillation and post-resuscitation myocardial function in a porcine model of prolonged cardiac arrest. J Am Coll Cardiol. 2008 May 20;51(20):1988-90. doi: 10.1016/j.jacc.2007.12.057. No abstract available.

Castren M, Nordberg P, Svensson L, Taccone F, Vincent JL, Desruelles D, Eichwede F, Mols P, Schwab T, Vergnion M, Storm C, Pesenti A, Pachl J, Guerisse F, Elste T, Roessler M, Fritz H, Durnez P, Busch HJ, Inderbitzen B, Barbut D. Intra-arrest transnasal evaporative cooling: a randomized, prehospital, multicenter study (PRINCE: Pre-ROSC IntraNasal Cooling Effectiveness). Circulation. 2010 Aug 17;122(7):729-36. doi: 10.1161/CIRCULATIONAHA.109.931691. Epub 2010 Aug 2.