Is venous congestion associated with reduced cerebral oxygenation and worse neurological outcome after cardiac arrest?

Abstract

BackgroundPost-cardiac arrest (CA) patients are at risk of secondary ischemic damage in the case of suboptimal brain oxygenation during an ICU stay. We hypothesized that elevated central venous pressures (CVP) would impair cerebral perfusion and oxygenation (venous cerebral congestion). The aim of the present study was to investigate the relationship between CVP, cerebral tissue oxygen saturation (SctO2) as assessed with near-infrared spectroscopy (NIRS) and outcome in post-CA patients.MethodsThis was an observational study in 48 post-CA patients with continuous CVP and SctO2 monitoring during therapeutic hypothermia.ResultsThe relationship between CVP and mean SctO2 was best described by an S-shaped, third-degree polynomial regression curve (SctO2 = −0.002 × CVP3 + 0.08 × CVP2 – 1.07 × CVP + 69.78 %, R2 0.89, n = 1,949,108 data points) with high CVP (>20 mmHg) being associated with cerebral desaturation. Multivariate linear regression revealed CVP to be a more important determinant of SctO2 than mean arterial pressure (MAP) without important interaction between both (SctO2 = 0.01 × MAP – 0.20 × CVP + 0.001 × MAP × CVP + 65.55 %). CVP and cardiac output were independent determinants of SctO2 with some interaction between both (SctO2 = 1.86 × CO – 0.09 × CVP – 0.05 × CO × CVP + 60.04 %). Logistic regression revealed that a higher percentage of time with CVP above 5 mmHg was associated with lower chance of survival with a good neurological outcome (cerebral performance category (CPC) 1–2) at 180 days (OR 0.96, 95 % CI 0.92–1.00, p = 0.04). In a multivariate model, the negative association between CVP and outcome persisted after correction for hemodynamic variables, including ejection fraction and MAP.ConclusionsElevated CVP results in lower brain saturation and is associated with worse outcome in post-CA patients. This pilot study provides support that venous cerebral congestion as indicated by high CVP may be detrimental for post-CA patients.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-016-1297-2) contains supplementary material, which is available to authorized users.

Pathophysiology and the Monitoring Methods for Cardiac Arrest Associated Brain Injury

“…In the observation of CA patients over a period of 6 h post-return-of-spontaneous-circulation (ROSC), they discovered that 40% of patients with an average MAP pressure above 70 mmHg were associated with a good neurological outcome [ 88 ]. A counter to the conclusion by Kilgannon and colleagues argues that central venous pressure (CVP) is a more accurate indicator of cerebral oxygen saturation than MAP [ 89 ]. A pilot study conducted by Ameloot and colleagues found that a prolonged CVP over 5 mmHg increased the likelihood of recovery with a poor neurological outcome [ 89 ].…”

“…A counter to the conclusion by Kilgannon and colleagues argues that central venous pressure (CVP) is a more accurate indicator of cerebral oxygen saturation than MAP [ 89 ]. A pilot study conducted by Ameloot and colleagues found that a prolonged CVP over 5 mmHg increased the likelihood of recovery with a poor neurological outcome [ 89 ]. Data analysis of simultaneously recorded CVP and cerebral tissue oxygen (SctO 2 ) content via near-infrared spectroscopy (NIRS) showed an association between a high CVP (>20 mmHg) and a decrease in SctO 2 content [ 89 ].…”

“…A pilot study conducted by Ameloot and colleagues found that a prolonged CVP over 5 mmHg increased the likelihood of recovery with a poor neurological outcome [ 89 ]. Data analysis of simultaneously recorded CVP and cerebral tissue oxygen (SctO 2 ) content via near-infrared spectroscopy (NIRS) showed an association between a high CVP (>20 mmHg) and a decrease in SctO 2 content [ 89 ]. Additional analysis between CVP and MAP showed CVP to associate more closely to changes in SctO 2 [ 89 ].…”

“…Data analysis of simultaneously recorded CVP and cerebral tissue oxygen (SctO 2 ) content via near-infrared spectroscopy (NIRS) showed an association between a high CVP (>20 mmHg) and a decrease in SctO 2 content [ 89 ]. Additional analysis between CVP and MAP showed CVP to associate more closely to changes in SctO 2 [ 89 ]. Unfortunately, the measurement of CVP requires the insertion of a venous catheter, a procedure that cannot be conducted on OHCA patients, specifically during CPR.…”

Central Venous Pressure (CVP) Reduction Associated With Higher Cardiac Output (CO) Favors Good Prognosis of Circulatory Shock: A Single-Center, Retrospective Cohort Study

“…Another possible mechanism may be that elevated CVP may influence pulmonary circulation and oxygenation, and MV, in turn, may affect CVP (6, 23, 24). In addition, there may be an effect of CVP on microcirculation perfusion (25), cerebral blood flow regulation (26), and other organ/tissue perfusion. Therefore, appropriately lower CVP levels are conducive to maintaining normal physiological organ function.…”