Optical Bedside Monitoring of Cerebral Blood Flow in Acute Ischemic Stroke Patients During Head-of-Bed Manipulation

This was first written about in Nov. 2011 and I bet not one single hospital in the world tried to implement this. Prove me wrong.
http://stroke.ahajournals.org/content/45/5/1269.abstract?etoc

1. Christopher G. Favilla, MD*;
2. Rickson C. Mesquita, PhD*;
3. Michael Mullen, MD;
4. Turgut Durduran, PhD;
5. Xiangping Lu, MD;
6. Meeri N. Kim, PhD;
7. David L. Minkoff, BA;
8. Scott E. Kasner, MD;
9. Joel H. Greenberg, PhD;
10. Arjun G. Yodh, PhD;
11. John A. Detre, MD

+ Author Affiliations

1. From the Departments of Neurology (C.G.F., M.M., X.L., S.E.K., J.H.G., J.A.D.), Physics and Astronomy (R.C.M., M.N.K., D.L.M., A.G.Y.), and Radiology (J.A.D.), University of Pennsylvania, Philadelphia, PA; Institute of Physics, University of Campinas, Campinas, Brazil (R.C.M.); and ICFO-Institut de Ciències Fotòniques, Castelldefels, Barcelona, Spain (T.D.).

1. Correspondence to John A. Detre, MD, Department of Neurology, University of Pennsylvania, 3400 Spruce St, 3 West Gates, Philadelphia, PA 19104-4283. E-mail detre@mail.med.upenn.edu

1. Guest Editor for this article was Markku Kaste, MD, PhD.
2. ↵* Drs Favilla and Mesquita are joint first authors and contributed equally.

Abstract

Background and Purpose—A primary goal of acute ischemic stroke (AIS) management is to maximize perfusion in the affected region and surrounding ischemic penumbra. However, interventions to maximize perfusion, such as flat head-of-bed (HOB) positioning, are currently prescribed empirically. Bedside monitoring of cerebral blood flow (CBF) allows the effects of interventions such as flat HOB to be monitored and may ultimately be used to guide clinical management.

Methods—Cerebral perfusion was measured during HOB manipulations in 17 patients with unilateral AIS affecting large cortical territories in the anterior circulation. Simultaneous measurements of frontal CBF and arterial flow velocity were performed with diffuse correlation spectroscopy and transcranial Doppler ultrasound, respectively. Results were analyzed in the context of available clinical data and a previous study.

Results—Frontal CBF, averaged over the patient cohort, decreased by 17% (P=0.034) and 15% (P=0.011) in the ipsilesional and contralesional hemispheres, respectively, when HOB was changed from flat to 30°. Significant (cohort-averaged) changes in blood velocity were not observed. Individually, varying responses to HOB manipulation were observed, including paradoxical increases in CBF with increasing HOB angle. Clinical features, stroke volume, and distance to the optical probe could not explain this paradoxical response.

Conclusions—A lower HOB angle results in an increase in cortical CBF without a significant change in arterial flow velocity in AIS, but there is variability across patients in this response. Bedside CBF monitoring with diffuse correlation spectroscopy provides a potential means to individualize interventions designed to optimize CBF in AIS.