RESUMO
AIM OF THE STUDY: Controlled sequential elevation of the head and thorax (CSE) during active compression decompression (ACD) cardiopulmonary resuscitation (CPR) with an impedance threshold device (ITD) has been shown to increase cerebral perfusion pressure and cerebral blood flow in previous animal studies as compared to the traditional supine position. The potential for this novel bundled treatment strategy to improve survival with intact neurological function is unknown. METHODS: Female farm pigs were sedated, intubated, and anesthetized. Central arterial and venous access were continuously monitored. Regional brain tissue perfusion (CerO2) was also measured transcutaneous. Ventricular fibrillation (VF) was induced and untreated for 10â¯min. Pigs were randomized to (1) Conventional CPR (C-CPR) flat or (2) ACDâ¯+â¯ITD CSE CPR that included 2â¯min of ACDâ¯+â¯ITD with the head and heart first elevated 10 and 8â¯cm, and then gradual elevation over 2â¯min to 22 and 9â¯cm, respectively. After 19â¯min of CPR, pigs were defibrillated and recovered. A veterinarian blinded to the intervention assessed cerebral performance category (CPC) at 24â¯h. A neurologically intact outcome was defined as a CPC score of 1 or 2. Categorical outcomes were analyzed by Fisher's exact test and continuous outcomes with an unpaired student's t-test. RESULTS: In 16 animals, return of spontaneous circulation rate was 8/8 (100%) with ACDâ¯+â¯ITD CSE and 3/8 (25%) for C-CPR (pâ¯=â¯0.026). For the primary outcome of neurologically intact survival, 6/8 (75%) pigs had a CPC score 1 or 2 with ACDâ¯+â¯ITD CSE versus 1/8 (12.5%) with C-CPR (pâ¯=â¯0.04). Coronary perfusion pressure (mmHg, mean⯱â¯SD) was higher with CSE at 18â¯min (41⯱â¯24 versus 10⯱â¯5, pâ¯=â¯0.004). rSO2 (%, mean⯱â¯SD) and ETCO2 (mmHg, mean⯱â¯SD) values were higher at 18â¯min with CSE (32⯱â¯9 versus 17⯱â¯2, pâ¯=â¯0.01, and 55â¯mmHg⯱â¯10 versus 21â¯mmHg⯱â¯4, pâ¯<â¯0.001), respectively. CONCLUSIONS: The novel bundled resuscitation approach of CSE with ACDâ¯+â¯ITD CPR increased favorable neurological survival versus C-CPR in a swine model of cardiac arrest.