The association of non-invasive cerebral and mixed venous oxygen saturation during cardiopulmonary resuscitation

Abstract

Mixed venous oxygen saturation (SvO(2)) is an accepted surrogate parameter for the ratio between oxygen delivery and demand and may thus be used to determine the adequacy of the function of the cardiopulmonary system. Cerebral oxygen saturation monitoring by near infrared spectroscopy is a non-invasive method for the determination of the cerebral oxygen delivery to demand ratio that is applicable outside the operating room or the intensive care unit and does not require calibration. The present case highlights the agreement of non-invasive cerebral and SvO(2) in an 87-year-old female cardiac surgery patient with severe aortic stenosis scheduled for transapical aortic valve replacement during prolonged cardiopulmonary resuscitation.

Cerebral Oximetry During Cardiac Arrest: A Multicenter Study of Neurologic Outcomes and Survival*

“…Thus, higher cerebral oxygenation maintained throughout CPR may effectively attenuate cerebral ischemic and subsequent reperfusion injury, whereas a high peak rSo 2 may facilitate ROSC. Progressive increases in coronary perfusion pressure (CPP) from 15 to 60 mm Hg have been shown to lead to an increased likelihood of ROSC (23), whereas CPP less than 15 mm Hg or an end-tidal Co 2 less than 10 mm Hg is largely incompatible with ROSC (23,24). Although these observations mirror our findings, the advantage of rSo 2 is that it also reflects the quality of cerebral oxygenation, a key factor in determining neurologic outcomes.…”

“…If, despite all interventions, rSo 2 remains less than 25%, then a poor outcome may be inevitable. However, there is potential to improve rSo 2 during CPR (15,24).…”

“…NIRS does not rely on pulsatile flow, enabling it to be used during CA (8). Although validated and used in many settings (8)(9)(10), few studies have examined its use during CA (11)(12)(13)(14)(15)(16). Although a number of small studies have indicated that ROSC is associated with higher rSo 2 during CPR in out-of-hospital CA (OHCA) and in-hospital CA (IHCA) (11)(12)(13)(14)(15)(16), they lacked the power to determine the accuracy and clinical utility of rSo 2 as a predictor of ROSC.…”

Near-infrared spectroscopy during cardiopulmonary resuscitation and after restoration of spontaneous circulation

“…The first commercially available human rSO 2 monitor (INVOS, Covidien, Michigan, USA) was described by McCormick et al [6]. Paarmann et al [7] describe a case of CPR in which both rSO 2 and venous oxygen saturation (SVO 2 ) was measured in parallel and they followed each other. Following the rSO 2 value gives critical care physicians a notion of the CO and how the organ or region measured is perfused.…”

“…Switching chest compression operator changes the rSO 2 measure [9,19]. Case reports of heart surgery patients suffering cardiac arrest report a change in rSO 2 in connection with start of chest compressions, initiation of cardiopulmonary bypass, and ROSC and consequently the sensitivity of rSO 2 to hemodynamic instability [20][21][22]. The latency to changes is not reported but reviewing the figures provided it seems like the change is prompt.…”