Anest. intenziv. Med. 2009;20(2):102-106

Evaluation of changes in brain tissue oxygen levels (PbtO₂) for detection of vasospasm in patients after subarachnoid haemorrhageIntensive Care Medicine - Original Paper

Ďuriš Kamil^1,*, Smrčka Martin¹, Ševčík Pavel², Gál Roman², Juráň Vilém¹, Neuman Eduard¹, Sova Marek¹, Vybíhal Václav¹, Kýr Michal³

¹ Neurochirurgická klinika LF MU a FN Brno

² Klinika anesteziologie, resuscitace a intenzivní medicíny LF MU a FN Brno

³ Institut biostatistiky a analýz, Masarykova univerzita Brno

Objective:
Evaluation of the impact of the admission clinical status of subarachnoid haemorrhage (SAH) patients (Hunt Hesse Score, HH3), the outcome (Glasgow Outcome Score, GOS) and the presence of vasospasm on the changes in the brain tissue oxygen levels (PbtO₂), in relation to changes of FiO₂ in mechanically ventilated patients.

Design:
Prospective interventional study.


Setting:
Neurosurgical Department of University Hospital, Department of Anaesthesia and Resuscitation, University Hospital.

Materials and methods:
We monitored PbtO₂ in patients with SAH due to aneurysm rupture for 10 days. Presence of vasospasms was repeatedly assessed with transcranial doppler (TCD). In patients on mechanical ventilation we performed the clinical trial. We increased the FiO₂ to 1.0 and measured the dynamics of changes of PbtO₂ simultaneously. Thus we obtained 26 continual measurements in the study group of 7 patients. The influence of vasospasm, the admission HH3 and GOS on changes of PbtO₂ after an increase of FiO₂ were evaluated. Mixed models analyses were used to evaluate the measured data.

Results:
In the study group we observed a significant difference in the dynamics of PbtO₂ levels after an increase of FiO₂ in relation to the patients' admission clinical status (HH3), outcome (GOS) and the presence of vasospasm. The levels of PbtO₂ after an increase in FiO₂ increased more in the patients with the better clinical status (HH3) and better outcome (GOS) (p < 0.001 in both parameters). In patients without vasospasm we found a significantly higher increase of PbtO₂ levels after increasing FiO₂ than in patients with vasospasm (p < 0.001).

Conclusion:
The dynamics of PbtO₂ levels were influenced by vasospasm. The changes of PbtO₂ levels after increasing FiO₂ are also associated with other factors (HH, GOS).

Keywords: brain tissue oximetry; vasospasm; subarachnoid hemorrhage; aneurysm of brain vessels

Received: November 20, 2008; Accepted: January 20, 2009; Published: April 1, 2009  Show citation