RESUMO
BACKGROUND: Transcranial sonography is a point-of-care tool recommended in intensive care units (ICU) to monitor brain injured patients. Objectives of the study was to assess feasibility and reliability of the third ventricle (V3) diameter measurement using transcranial sonography (TCS) compared to brain computed-tomography (CT), the gold standard measurement, and to measure the TCS learning curve. DESIGN: prospective study, in a 16-bed neurological ICU in an academic hospital. Every consecutive brain injured adult patient, who required a brain CT and TCS monitoring were included. The V3 diameter was blindly measured by TCS and CT. Intraclass correlation coefficient (ICC) and Bland-Altman plot were used to assess the reliability and agreement between TCS and CT V3 measurements. Diagnosis performance of the V3 diameter using TCS to detect hydrocephalus was measured. Absolute difference between V3 measurement by residents and experts was measured consecutively to assess the learning curve. RESULTS: Among the 100 patients included in the study, V3 diameter could be assessed in 87 patients (87%) from at least one side of the skull. Both temporal windows were available in 70 patients (70%). The ICC between V3 diameter measured by TCS and CT was 0.90 [95% CI 0.84-0.93] on the right side, and 0.92 [0.88-0.95] on the left side. In Bland-Altman analysis, mean difference, standard deviation, 95% limits of agreement were 0.36, 1.52, - 2.7 to 3.3 mm, respectively, on the right side; 0.25, 1.47, - 2.7 to 3.1 mm, respectively, on the left side. Among the 35 patients with hydrocephalus, V3 diameters could be measured by TCS in 31 patients (89%) from at least one side. Hydrocephalus was, respectively, excluded, confirmed, or inconclusive using TCS in 35 (40%), 25 (29%) and 27 (31%) of the 87 assessable patients. After 5 measurements, every resident reached a satisfactory measurement compared to the expert operator. CONCLUSION: TCS allows rapid, simple and reliable V3 diameter measurement compared with the gold standard in neuro-ICU patients. Aside from sparing irradiating procedures and transfers to the radiology department, it may especially increase close patient monitoring to detect clinically occult hydrocephalus earlier. Further studies are needed to measure the potential clinical benefit of this method. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02830269.
RESUMO
BACKGROUND AND OBJECTIVE: The temporal bone window (TBW) for transcranial Doppler (TCD) often fails to insonate the anterior cerebral artery (ACA). The frontal bone window (FBW) has never been evaluated in intensive care units (ICU). The main objective was to determine the ability of the FBW to assess ACA velocities in critically ill patients. METHODS: A prospective study was conducted in two ICUs of the Montpellier University Hospital (France), between November 2014 and September 2016. Adult patients admitted to ICU for brain injury, with a Glasgow Coma Scale score ≤ 13, were enrolled within 3 days after admission. A first TCD examination was carried out bilaterally through the TBW and FBW by an intensivist expert in TCD, repeated by the same examiner, and 15 min later by an intensivist certified in TCD, designated as non-expert, blinded. The success of the FBW examinations was defined by the ability to measure the ACA velocities. Intra- and interobserver agreements were analyzed according to the Bland and Altman method. RESULTS: A total of 147 patients were analyzed. The FBW succeeded in insonating the ACA in 66 patients [45%, CI (37-53)], 45 bilaterally and 21 unilaterally. For 16 patients (11%), the FBW was the only way to measure ACA velocities. By combining the two techniques, the ACA success rate increased from 62% CI (54-70) to 73% CI (65-79) (P = 0.05). Intra- and interobserver mean biases and 95% limits of agreement for ACA systolic velocity measurements through the FBW were 1 (- 33 to 35) and 2 (- 34 to 38) cm s-1, respectively. For paired TBW and FBW measures of ACA velocities, mean biases (± SD) for ACA systolic, and mean and diastolic velocities were relatively close to zero, but negatives (- 7 ± 33, - 2 ± 19, - 1 ± 15 cm s-1, respectively), highlighting that ACA velocities were lower with the FBW (A2 segment) than TBW (A1 segment). The correlation coefficient for ACA systolic velocities measured by the FBW and TBW was R = 0.47, CI (0.28-0.62). No risk factors for failure of the FBW were identified. CONCLUSIONS: In ICU, the FBW was able to insonate the ACA in 45% of patients admitted for brain injury, without the use of contrast agents. The FBW could improve the detection of ACA vasospasms.
