Jugular venous oximetry is a method of analyzing the balance
between oxygen supply and demand to the brain. The oxygen saturation
of blood draining from the brain into the jugular bulb is continuously
measured providing an indirect measure of oxygen extraction by the
Definitions and Terms
- ▪ Jugular venous bulb: Dilation of the internal jugular
vein in the jugular fossa of the temporal bone
- ▪ SjvO2: Jugular venous oxygen saturation
- ▪ AVjDO2: Arteriovenous jugular oxygen content (Hgb × 1.34[SaO2 − SjO2] + 0.003[Pao2 − PvO2])
- ▪ CaO2: Arterial oxygen content saturation
- ▪ CjvO2: Jugular venous oxygen saturation
- ▪ CeO2: Cerebral extraction of oxygen (SaO2 [%] − SjvO2 [%])
- ▪ CMRO2: Cerebral metabolic rate of oxygen
- ▪ O2ER: Global cerebral oxygen extraction ratio
- ▪ CMRL: Cerebral metabolic rate of lactate
- ▪ AVDL: Arteriovenous difference of lactate
- ▪ LOI: Lactate Index (AVDL/AVDO2 [ischemia > 0.08])
- ▪ Patient consent should be obtained prior to performance
of the procedure and the site should be prepped and draped as described
in Section 1 (Figure 19-1).
- ▪ The jugular vein is cannulated in the usual fashion, and
the SjvO2 catheter is threaded retrograde until it reaches
the roof of the jugular bulb, at which point some resistance will
be felt (usually 13-15 cm from the skin).
- ▪ The catheter should then be withdrawn approximately 1 cm
and monitoring initiated.
- ▪ A skull x-ray is performed after insertion to verify correct
position of the catheter tip.
- ▪ Normal SjvO2 is between 55% to 70%.
- ▪ Normal AVjDO2 is 3.5 to 8 mL/dL.
- ▪ Normal CeO2 is 24% to 42%.
- ▪ SjvO2
- —Greater than 75% implies “luxury
- —Less than 50% represents hypoperfusion
- —Less than 40% represents ischemia
Clinical Pearls and Pitfalls
- ▪ The signal
quality indicator is a measure of the quality of the signal received
at the tip of the catheter; poor signal quality may indicate clotting
at the tip or that the tip is up against the vessel wall—the
catheter should be flushed and/or the head repositioned.
- ▪ Normal SjvO2 are
possible even in the face of significant brain pathology:
- —Focal ischemia may not be apparent.
- —Venous drainage may be asymmetric.
- —Infratentorial (brainstem, cerebellum) injuries
are not monitored by jugular venous drainage.
- ▪ Jugular venous monitoring is contraindicated in coagulopathy,
impaired venous drainage, neck trauma, tracheostomy (risk of infection),
cervical spine injuries (difficulty of cannulation), and local infection.
Woodman T, Robertson CS. Jugular venous oxygen saturation monitoring.
In: Narayan RK, Wilberger JE, ...