|Trends||Dementia||Sonothrombolysis||ICP Brain pressure||Parkinson|
The brain is the human organ, which is most sensitive to hypoxia. Hence, the brain perfusion is the major success parameter during cardio-pulmonary resuscitation (CPR). An assessment of effectiveness is usually only possible by evaluation of clinical signs (e.g. pupil width) or plethysmographic derived peripheral oxygen saturation (Cave: good specificity, worse sensitivity). TCD offers a method to derive intracerebral blood flow velocities as a parameter of cerebral perfusion with a high temporal resolution (beat-to-beat) (Blumenstein et al., 2010).
In the last years, an interesting scientific focus was on evaluation of blood flow patterns following successful CPR (ROSC = return of spontaneous circulation) to assess patient´s clinical outcome. Alvarez-Fernandez postulated in 2011 that TCD examinations might help to identify irreversibly neurologically impaired patients after ROSC to reduce unreasonable and ineffective treatment, which may have harmful side effects. Previously, also Wessels et al. (2006) could demonstrate a significant association between TCD parameters and prognosis following ROSC.
Although some studies assume that impaired cerebral haemodynamics after ROSC draw conclusion on clinical outcome, it remains to be determined which parameter (possibly: max. peak systolic flow after 4 or 72 h??) can provide useful information since randomized trials are not available so far.
This needs to be discussed controversially, especially regarding ethical aspects:
Should a doctor refuse a patient, who is supposed to have high likelihood of bad clinical outcome, the best available treatment??
It is noncontroversial that a real-time TCD monitoring is a valuable parameter of cerebral blood flow. Because of the device size and insufficient device mobility, nevertheless, it is difficult to put it into practice.