[The effectiveness of a correlation diagram of the echographic and haemodynamic patterns in the brain]. / Rendimiento de un diagrama de correlacion entre patrones ecograficos y hemodinamicos cerebrales.

INTRODUCTION: Transcranial Doppler (TCD) constitutes a valuable method for managing acute/critical neurological patients and it would therefore be interesting to reduce, as far as possible, the complexity involved in interpreting its findings. AIMS: The Objective of this study was to design and validate a correlation diagram of the echographic patterns and acute haemodynamic situations in the brain that makes it easier to teach and optimises the effectiveness of TCD as a diagnostic aid. MATERIALS AND METHODS: A diagram that represents the average speed and pulsatility index on a system of coordinates. Five fundamental echographic patterns were identified and the most frequent acute cerebral haemodynamic situations are detailed for each of them. The value of the diagram was tested in resident doctors with varying degrees of knowledge of TCD. In the first phase with no diagram (evaluation A), the interpretation of the TCD and diagnosis of the haemodynamic situation in the brain were evaluated in nine clinical cases. In the second phase, with a diagram (evaluation B), they were asked to draw up new reports on the same cases. We compared the number of times they were right in the two evaluations. RESULTS: A total of 216 echographic reports were obtained. The mean number of correct answers in evaluation A was 2, interquartile range (0.25 3.75). In evaluation B the number of correct answers rose to 4 (3.25 6.75) (p= 0.005). Using the diagram increased the diagnostic capacity of all the residents, but especially so in those with less training. CONCLUSIONS: Use of the diagram makes it easier for people who are not experts to learn to interpret TCD findings in acute/critical neurological situations.

[The usefulness of transcranial Doppler ultrasonography in the early phase of head injury]. / Utilidad del Doppler transcraneal en la fase precoz del traumatismo craneoencefálico.

OBJECTIVES: 1) To know the transcranial Doppler (TCD) patterns in the early phase of the severe and moderate head injury and its prognostic implications. 2) To ascertain the TCD measurements concordance among different operators. MATERIAL AND METHODS: A prospective observational study in 275 consecutive intensive care unit patients with severe or moderate head injury was designed. Within 12 hrs. of the traumatic event a TCD study was done and a second one within the first 24 hrs. All patients were managed following a protocol made with the aim of promoting the early evacuation of the intracranial space occupying mass, preventing delayed brain damage and keeping the intracranial pressure (ICP) < 20 mm Hg and the cerebral perfusion pressure (CPP) > 60 mm Hg. The patient outcome was categorized with the Glasgow Outcome Score (GOS) at the discharge of the ICU. The mean velocity (MV) and the pulsatily index (PI) were measured in both middle cerebral arteries (MCA) and in the intracranial part of the internal carotid arteries in order to calculate the Lindegaard index. The presence of hypoperfusion, hyperaemia, vasospasm and cerebral circulatory arrest was registered. The presence of high intracranial pressure (HICP), the ICP peak and mode, the lowest CPP, the CPP mode, the minor medium arterial pressure (MAP) and the MAP mode were also recorded. A concordance analysis was made to ascertain the validity of the TCD data obtained by different operators. RESULTS: The concordance analysis among observers showed a kappa index of 0.7863 (p < 0.0001). The median stay in ICU was 7 days (Q1-Q3 of 3-15 days). The intra-ICU mortality was 20.72% (57/275) and the 53.44% of patients (147/275) showed favourable outcome (GOS 4-5) at the discharge of the ICU. The initial TCD showed a MV decreased and a PI increased in the MCA. Eighty of the e 275 patients showed a normal haemodynamic pattern whereas the pattern was abnormal in the remaining 195, degrees the hypoperfusion pattern predominated overall (181/275, 61.87%). HIPO was registered in 123 patients (58.01) an not in 89 (41.99%). A statistic significant correlation was found between the HICP and the DTC data. The early hypoperfusion pattern was related with a higher incidence of HICP (p > 0.05). The decrease in the MV and the increase in the PI were significantly associated with a higher mortality and a worse functional outcome (except for the MV within the first day). The PI was high within the first 24 h in the group of patients who died but was normalised among the survivals group. CONCLUSIONS: Early TCD detects a cerebral hypoperfusion status in the severe and moderate head injury that may imply therapeutic considerations. This hypoperfusion strongly correlates with the severity of the injury, the incidence of HICP and the functional outcome at the ICU discharge. In experienced hands, TCD measurements are reliable when done by different operators.