Is jugular bulb oximetry monitoring associated with outcome in out of hospital cardiac arrest patients?

Cerebral protection against secondary hypoxic-ischemic brain injury is a key priority area in post-resuscitation intensive care management in survivors of cardiac arrest. Nevertheless, the current understanding of the incidence, diagnosis and its' impact on neurological outcome remains undetermined. The aim of this study was to evaluate jugular bulb oximetry as a potential monitoring modality to detect the incidences of desaturation episodes during post-cardiac arrest intensive care management and to evaluate their subsequent impact on neurological outcome. We conducted a prospective, observational study in unconscious adult patients admitted to the intensive care unit who had successful resuscitation following out of hospital cardiac arrest of presumed cardiac causes. All the patients were treated as per European Resuscitation Council 2015 guidelines and they received jugular bulb catheter. Jugular bulb oximetry measurements were performed at six hourly intervals. The neurological outcomes were evaluated on 90th day after the cardiac arrest by cerebral performance categories scale. Forty patients met the eligibility criteria. Measurements of jugular venous oxygen saturation were performed for 438 times. Altogether, we found 2 incidences of jugular bulb oxygen saturation less than 50% (2/438; 0.46%), and 4 incidences when it was less than 55% (4/438; 0.91%). The study detected an association between SjVO and CO (r = 0.26), each 1 kPa increase in CO led to an increase in SjvO by 3.4% + / - 0.67 (p < 0.0001). There was no association between SjvO and PaO or SjvO and MAP. We observed a statistically significant higher mean SjvO (8.82% + / - 2.05, p < 0.0001) in unfavorable outcome group. The episodes of brain hypoxia detected by jugular bulb oxygen saturation were rare during post-resuscitation intensive care management in out of hospital cardiac arrest patients. Therefore, this modality of monitoring may not yield any additional information towards prevention of secondary hypoxic ischemic brain injury in post cardiac arrest survivors. Other factors contributing towards high jugular venous saturation needs to be considered.