Objectives At this single centre, tri-modal monitoring of ICP, temperature and direct brain tissue oxygen tension (PbtO2) is used to guide management of delayed cerebral ischaemia (DCI). We describe our experience of PbtO2 monitoring and its relationship with symptoms of DCI, regional cerebral blood flow (rCBF, perfusion imaging), intra-arterial chemical angioplasty and CSF diversion.

Design Prospective cohort.

Subjects Patients with aSAH who underwent over 24 hours of multi-modal PbtO2, temperature and intracranial pressure (ICP) monitoring via a Raumedic NEUROVENT-PTO probe.

Methods Longitudinal analysis of PbtO2 values, presented as mmHg (mean±SD).

Results Analysis of 1392 hours of tri-modal monitoring in 13 SAH patients. PbtO2 decreases >50% consistently reproduced focal neurological deficit. Symptomatic PbtO2 values ranged from 12–20 mmHg. Of the six patients who had reduced rCBF, all had a mean PbtO2 <15 mmHg. Five patients underwent intra-arterial chemical angioplasty (10 mg Verapamil in 100 ml NaCl over 30–40 mins). PbtO2 increased by at least 30% for 3.4±0.47 hours. CSF diversion resulted in a sustained mean increase in PbtO2 of 7.6±2.94 mmHg over the first 5 min (p=0.034).

Conclusions PbtO2 <15 mmHg may predict development of a clinical deficit. Chemical angioplasty resulted in a pronounced but short-lived increase in PbtO2. CSF diversion resulted in a persistent increase in PbtO2. PbtO2 targeted management may be a valuable addition to the clinicians’ arsenal against DCI.