The real-time evaluation of chest compression during cardiopulmonary resuscitation is important to increase the chances of survival from a cardiac arrest (CA). In addition, cerebral oxygen level measured by near-infrared spectroscopy (NIRS) plays an important role as an indicator of return of spontaneous circulation. Recently, we developed a new method to improve the quality of chest compression using a thoracic pump in conjunction with the classic cardiac pump in a rat asphyxia CA model. This study evaluated the quality of chest compression using NIRS in male Sprague-Dawley rats. NIRS was attached between the nasion and the upper cervical spine, and rats underwent 10 minute asphyxia CA. After CA, we alternately performed three different types of chest compression (cardiac, thoracic, and cardiac plus thoracic pumps) every 30 seconds for up to 4 and a half minutes. We measured the oxyhemoglobin (Oxy-Hb), deoxyhemoglobin (Deoxy-Hb), and tissue oxygenation index (TOI) and compared these values between the groups. Oxy-Hb was significantly different among the groups (cardiac, thoracic, and cardiac plus thoracic, 1.5 ± 0.9, 4.4 ± 0.7, and 5.9 ± 2.1 μmol/L, p < 0.01, respectively), while Deoxy-Hb and TOI were not (Deoxy-HB -2.7 ± 1.2, -1.1 ± 3.2, and -1.6 ± 10.1 μmol/L; TOI, 1.8 ± 1.8, 5.5 ± 1.3, and 9.5 ± 8.0%, respectively). Oxy-Hb showed potential to evaluate the quality of chest compression in a rat asphyxia CA model.
Keywords: Cardiac arrest; Cerebral blood oxygenation (CBO); Near-infrared spectroscopy (NIRS); Oxyhemoglobin (Oxy-Hb); Quality of chest compression.