Arterial-jugular bulb differences in pCO₂, lactate, serum sodium and C-reactive protein in neurocritical patients

Introduction

Several reports indicate the potential usefulness of monitoring brain metabolic parameters and their correlation with the system [1–4]. We want to establish differences and correlation in pCO₂, lactate, serum sodium and C-reactive protein (CRP) between arterial and jugular venous bulb blood.

Methods

An observational study. Between 1 January and 31 October 2013 we included neurocritical patients (NCP) with multimodal neuromonitoring (MMN). Daily samples of arterial blood and venous jugular bulb blood were obtained for measuring pCO₂, lactate, serum sodium and CRP.

Results

There were 45 NCP, six (13%) with MMN (five men). Mean age was 37 ± 11 years (35 to 61). Diagnostics: two TBI, two SAH, one stroke, one lupus encephalitis. APACHE II was 27 ± 6.5 (25 to 39). Glasgow Coma Scale at admission was 14 ± 4 (4 to 14). pCO₂ (mmHg): arterial 41 ± 6.3 versus jugular 45 ± 7.4 (r = 0.7, P = 0.007). Lactate (mg/dl): arterial 11 ± 5.6 versus jugular 13.5 ± 3.9 (r = 0.7, P = 0.9). Sodium (mEq/dl): arterial 141 ± 4.5 versus 141 ± 4.4 (r = 0.8, P = 0.15). CRP (mg/dl): arterial 8 ± 7.4 versus 17 ± 11.6 (r = 0.9, P < 0.001). The correlation and trend curves are shown in Figure 1.

Figure 1

abstract P461

Conclusion

A suitable correlation is observed for the arterial-jugular bulb in different variables. There is a significant difference in CRP and pCO₂ values being persistently higher in the jugular, particularly for CRP. Studies are required to define its interpretation and potential usefulness.