Using the relationship between brain tissue regional saturation of oxygen and mean arterial pressure to determine the optimal mean arterial pressure in patients following cardiac arrest: A pilot proof-of-concept study. (September 2016)

• Record Type: Journal Article
• Authors: Sekhon, Mypinder S.; Smielewski, Peter; Bhate, Tahara D.; Brasher, Penelope M.; Foster, Denise; Menon, David K.; Gupta, Arun K.; Czosnyka, Marek; Henderson, William R.; Gin, Kenneth; Wong, Graham; Griesdale, Donald E.
• Is Part Of: Resuscitation. Volume 106(2016)
• Page Start: 120
• Page End: 125
• Publication Date: 2016-09
• Subjects: AHA American Heart Association -- CCU coronary care unit -- COx correlational coefficient between MAP and rSO2 -- CPP cerebral perfusion pressure -- FVd/FVm flow velocity diastolic/mean -- HIBI hypoxemic ischemic brain injury -- ICP intracranial pressure -- ICU intensive care unit -- IQR interquartile range -- MAP mean arterial pressure -- MAPOPT optimal mean arterial pressure -- ONSD optic nerve sheath diameter -- ROSC return of spontaneous circulation -- rSO2 regional saturation of oxygen -- SD standard deviation -- TBI traumatic brain injury -- TCD transcranial Doppler; Cardiac arrest -- Cerebral autoregulation -- Cerebral oximetry; Resuscitation -- Periodicals; Resuscitation -- Periodicals; Réanimation -- Périodiques; Electronic journals; 616.025
• DOI: 10.1016/j.resuscitation.2016.05.019
• Languages: English
• ISSNs: 0300-9572

Abstract

Abstract: Introduction: Prospectively assess cerebral autoregulation and optimal mean arterial pressure (MAPOPT ) using the dynamic relationship between MAP and regional saturation of oxygen (rSO2 ) using near-infrared spectroscopy. Methods: Feasibility study of twenty patients admitted to the intensive care unit following a cardiac arrest. All patients underwent continuous rSO2 monitoring using the INVOS ® cerebral oximeter. ICM+ ® brain monitoring software calculates the cerebral oximetry index (COx) in real-time which is a moving Pearson correlation coefficient between 30 consecutive, 10-s averaged values of MAP and correspond rSO2 signals. When rSO2 increases with increasing MAP (COx ≥0.3), cerebral autoregulation is dysfunctional. Conversely, when rSO2 remains constant or decreases with increasing MAP (COx <0.3), autoregulation is preserved. ICM+ ® fits a U-shaped curve through the COx values plotted vs. MAP. The MAPOPT is nadir of this curve. Results: The median age was 59 years (IQR 54–67) and 7 of 20 were female. The cardiac arrest was caused by myocardial infarction in 12 (60%) patients. Nineteen arrests were witnessed and return of spontaneous circulation occurred in a median of 15.5 min (IQR 8–33). Patients underwent a median of 30 h (IQR 23–46) of monitoring. COx curves and MAPOPT were generated in all patients. The mean overall MAP and MAPOPT were 76 mmHg (SD 10) and 76 mmHg (SD 7), respectively. MAP was outside of 5 mmHg from MAPOPT in 50% (SD 15) of the time. Out of the 7672 5-min averaged COx measurements, 1182 (15%) were at 0.3 or above, indicating absence of autoregulation. Multivariable polynomial fractional regression demonstrated an increase in COx with increasing temperature ( P = 0.008). Conclusions: We demonstrated the feasibility to determine a MAPOPT using cerebral oximetry in patients after cardiac arrest.