155| © www.globalsciencepg.org Biolife | 2017 | Vol 5 | Issue 2
B I O L I F E R E S E A R C H A R T I C L E
Evaluation of cerebral autoregulation using transcranial
doppler ultrasound in patients with moderate and severe
traumatic brain injuries
Taysser Zaytoun
1
, Amr Abdalla
2
, Bassem Beshay
3
, Ahmed Elbeheiry
4
, Moustafa Shebl
5
1-3,5
Department of Critical Care Medicine, Faculty of Medicine, University of Alexandria.
2
Department of Radiodiagnosis, Faculty of Medicine, University of Alexandria
Email: : doctor.islam.ahmed@gmail.com
ABSTRACT
Introduction: Traumatic brain injury (TBI) has been increasing with greater incidence. It remains a
leading cause of death. Cerebral pressure autoregulation impairment is a well-known pathology after
TBI that worsens the prognosis and outcome. Transcranial Doppler (TCD) can be used to assess
Transient Hyperaemic response ratio (THRR) after carotid compression which is a well demonstrated
valid index for cerebral autoregulation. A relative increase in mean flow velocity (MFV) of middle
cerebral artery (MCA) above the baseline following the release of carotid compression denotes
preserved autoregulation and sequentially predicts good outcome, whereas absence of such response
indicates altered autoregulation with poor outcome.
Design: Observational prospective cohort study
Setting: Alexandria Main University Hospital, Department of Critical Care Medicine
Patients & Methods: 120 patients with moderate or severe TBI according to Glasgow Coma Score
(GCS) underwent daily TCD for 5 days post trauma. The primary end point is the Glasgow outcome
score (GOS) as a measure of outcome to assess THRR after carotid compression as an indicator of
cerebral pressure autoregulation as a predictor of GOS as well as a being prognostic tool. Other
measures of TCD as MFV of MCA and Pulstility Index (PI) were also used as predictors of GOS and
correlated with THRR. The length of stay as well as mortality were recorded and correlated to THRR.
Results: There was a significant correlation between THRR and GOS (patients with THRR ≥ 1 had
favorable outcome). There was also significant correlation between THRR and length of stay and
mortality. Also significant correlation between THRR and MFV as well as PI was found.
Conclusion: THRR provides a clinically useful index of cerebral autoregulation. THRR after carotid
compression is a good predictor of GOS as well as being a prognostic tool in patients with moderate
and severe TBI.
Keywords: Critical; Trauma; Injury; Transcranial; Ultrasound
INTRODUCTION
Traumatic brain injury (TBI) is a major public health and
socio-economic problem worldwide. It one of the leading
causes of death and disability among young adults.
Prolonged disability is common in those who survive.
(1)
Every year, approximately 1.5 million people die from
TBI. The major burden (90%) is in developing
countries.
(2,3)
It is well demonstrated that neurological outcome
after TBI depends on the severity of initial injuries and
the extent of secondary brain damage such as ischemia
and hypoxia
(4)
. Prevention and treatment of such
secondary injuries are mandatory and are considered a
major concern of ICU management. In this situation, the
maintenance of adequate cerebral blood flow (CBF) is
critical
(5,6)
.
AN INTERNATIONAL QUARTERLY JOURNAL OF BIOLOGY & LIFE SCIENCES
5(2):155-163
ISSN (online): 2320-4257
www.biolifejournal.com
How to Site This Article:
Taysser Zaytoun, Amr Abdalla, Bassem Beshay,
Ahmed Elbeheiry, Moustafa Shebl (2017). Evaluation
of cerebral autoregulation using transcranial doppler
ultrasound in patients with moderate and severe
traumatic brain injuries. Biolife. 5(2), pp 155-163.
doi:10.17812/blj.2017.5202
Received: 5 Februaryy 2017; Accepted: 12 March, 2017;
Published online: 5 April 2017