PaCO2-management in the neuro-critical care of patients with subarachnoid hemorrhage

Abstract

The partial pressure of carbon dioxide (PaCO2) in the arterial blood is a strong vasomodulator affecting cerebral blood flow and the risk of cerebral edema and ischemia after acute brain injury. In turn, both complications are related to poor outcome in patients with aneurysmal subarachnoid hemorrhage (aSAH). We aimed to analyze the effect of PaCO2 levels on the course and outcome of aSAH. All patients of a single institution treated for aSAH over 13.5 years were included (n = 633). Daily PaCO2 values from arterial blood gas measurements were recorded for up to 2 weeks after ictus. The study endpoints were: delayed cerebral ischemia (DCI), need for decompressive craniectomy due to increased intracranial pressure > 20 mmHg refractory to conservative treatment and poor outcome at 6-months follow-up (modified Rankin scale > 2). By correlations with the study endpoints, clinically relevant cutoffs for the 14-days mean values for the lowest and highest daily PaCO2 levels were defined by receiver operating characteristic curve analysis. Association with the study endpoints for the identifies subgroups was analyzed using multivariate analysis. The optimal range for PaCO2 values was identified between 30 and 38 mmHg. ASAH patients with poor initial condition (WFNS 4/5) were less likely to show PaCO2 values within the range of 30–38 mmHg (p < 0.001, OR = 0.44). In the multivariate analysis, PaCO2 values between 30 and 38 mmHg were associated with a lower risk for decompressive craniectomy (p = 0.042, aOR = 0.27), DCI occurrence (p = 0.035; aOR = 0.50), and poor patient outcome (p = 0.004; aOR = 0.42). The data from this study shows an independent positive association between low normal mean PaCO2 values during the acute phase of aSAH and patients’ outcome. This effect might be attributed to the reduction of intracranial hypertension and alterations in the cerebral blood flow.

A predictive nomogram for assessing the likelihood of consciousness disturbances in individuals with chronic obstructive pulmonary disease

“…Our study revealed that the elevated PaCO 2 levels in COPD patients are an independent risk factor for developing delirium or cognitive impairment. Arterial blood PaCO 2 levels can impact cerebral blood ow and intracranial pressure, with higher levels of PaCO 2 resulting in increased intracranial pressure [19] .…”

Evaluation of markers of cerebral oxygenation and metabolism in patients undergoing clipping of cerebral aneurysm under total intravenous anesthesia versus inhalational anesthesia: A prospective randomized trial (COM-IVIN trial)

“…The alteration in CBF, which happens secondary to a change in PaCO 2 , is termed as cerebrovascular reactivity to carbon dioxide (CVR-CO 2 ). [ 9 ] Studies have shown that both TIVA and INHA have variable effects on CVR-CO 2 , and the effect of these agents on CVR also differs with many physiological and pathologic conditions. [ 10 11 ] This also might have influenced the variations observed by the authors.…”

The value of ventricular measurements in the prediction of shunt dependency after aneurysmal subarachnoid hemorrhage

“…Aneurysms were secured by microsurgical clipping or endovascular coiling, mostly within 24 h after admission. Post-interventional intensive care treatment of SAH patients in our center was already described elsewhere [ 11 , 43 ] [ 10 , 42 ]. In short, conservative management consisted of maintenance of normovolemia, mean arterial pressure >70 mmHg, and oral nimodipine for the first 21 days after ictus.…”