Abstract 2500: Impact of Hemoglobin Level on Return of Spontaneous Circulation in Sudden Cardiac Arrest Patients
OBJECTIVES: Hemoglobin (Hb) level is related to blood viscosity, oxygen delivery, nitric oxide availability, and oxygen radical scavenging capacity. Therefore, Hb may play a role on ischemia and reperfusion during cardiac arrest. We have previously demonstrated that return of spontaneous circulation (ROSC) in sudden cardiac arrest patients was associated with low Hb level in a single-center study, however, the impact of Hb level on ROSC has been yet clarified. The aim of this study is to evaluate the relationship between Hb level and ROSC in patients with cardiac arrest in a multicenter observational manner.
METHODS: From the SOS-KANTO Study Database (retrospective multicenter observational study using Utstein templates), 232 witnessed out-of-hospital cardiac arrest patients with presumed cardiac etiologies with bystander CPR were extracted. Of those, 201 patients (male 145, median 62 y/o) met following inclusion criteria; age: 12 to 84 y/o, body temperature on hospital arrival: 34.0 to 37.9 °C, Hb level on arrival: 6.0 to 17.9 g/dl. Because median Hb level was 13.1 g/dl, we assigned these patients into low (Hb<13.0 g/dl, 95 patients) and high Hb group (Hb≥13.0, 106), and analyses were each performed.
RESULTS: Of these 201 patients, 45.6% presented initial rhythm of Vfib/Vtach and 99 49.3% were led to ROSC. Of the patients with Vfib/Vtach, 59.8% showed ROSC and its incidence was significantly higher than those without Vfib/Vtach (40.4%, OR=2.20, 95%CI: 1.25 to 3.87). Among the patients with Vfib/Vtach, there was no significant difference in the incidence of ROSC between low and high Hb group (63.0%, 58.5%, respectively, P=0.82), while ROSC in patients without Vfib/Vtach was more frequent in low Hb group than in high Hb group (50.0%, 24.4%, respectively, P<0.01). Mantel-Haenzel Chi-square test showed that the incidence of ROSC was significantly higher in low Hb group (P=0.04). Logistic regression analysis revealed low Hb level and Vfib/Vtach as independent predictors for ROSC (OR=2.82, 95% CI: 1.40 to 5.68, OR=2.15, 95%CI: 1.06 to 4.36, respectively).
CONCLUSIONS: Low Hb level was associated with successful resuscitation with ROSC even in patients with asystole and PEA. These results suggest that hemodilution is advantageous for cardiac resuscitation.