Work

Jugular bulb venous to arterial carbon dioxide gradient is associated with treatment-responsive phenotypes of hypoxic-ischemic brain injury

Year: 2025

Type: article

Abstract: The difference between the jugular bulb venous and arterial carbon dioxide (CO 2 ) tension, the cerebral pCO 2 gap, is a marker of global tissue perfusion and can be affected by various mechanisms that underlie hypoxic-ischemic brain injury (HIBI). We hypothesized the CO 2 gap and SjvO 2 together could identify treatment responsive pathophysiology among those with abnormally elevated SjvO 2 . In this retrospective study including post-arrest patients, we quantified the relationship between pCO 2 gap and SjvO 2 using hierarchical regression. Among patients with elevated SjvO 2 , we assessed whether pCO 2 gap predicted response to treatment with hyperosmolar therapy using an interaction between time, treatment, and pCO 2 gap. We assessed the association between pCO 2 gap and indicators of HIBI using mixed regression models. Among the 109 patients included, pCO 2 gap was lower among patients with normal (β = -4.3; 95% CI, -5.6 to -3.1) or high SjvO 2 (β = -7.8; 95% CI, -9.1 to -6.6) compared to low SjvO 2 . In our interaction model, treatment with hyperosmolar therapy was associated with a 14.4 mmHg decrease in SjvO 2 (95% CI, -18.4 to -10.3) among those with a high pCO 2 gap, but not those with normal pCO 2 gap. pCO 2 gap was significantly lower among patients with burst-suppression with identical bursts compared to those without (β = -1.8; 95% CI, -2.8 to -0.9). When interpreted with SjvO 2 , the cerebral pCO 2 gap may uncover covert cerebral dysfunction, and can identify treatment-responsive causes of elevated SjvO 2 . Thus, the pCO 2 gap may be a useful adjunct for phenotyping HIBI.

Source: Resuscitation Plus

DOI: 10.1016/j.resplu.2025.101136