Noninvasive Intracranial Pressure Determination in Patients with Subarachnoid Hemorrhage.

Intracranial pressure (ICP) should ideally be measured in many conditions affecting the brain. The invasiveness and associated risks of the measurement modalities in current clinical practice restrict ICP monitoring to a small subset of patients whose diagnosis and treatment could benefit from ICP measurement. To expand validation of a previously proposed model-based approach to continuous, noninvasive, calibration-free, and patient-specific estimation of ICP to patients with subarachnoid hemorrhage (SAH), we made waveform recordings of cerebral blood flow velocity in several major cerebral arteries during routine, clinically indicated transcranial Doppler examinations for vasospasm, along with time-locked waveform recordings of radial artery blood pressure (APB), and ICP was measured via an intraventricular drain catheter. We also recorded the locations to which ICP and ABP were calibrated, to account for a possible hydrostatic pressure difference between measured ABP and the ABP value at a major cerebral vessel. We analyzed 21 data records from five patients and were able to identify 28 data windows from the middle cerebral artery that were of sufficient data quality for the ICP estimation approach. Across these windows, we obtained a mean estimation error of -0.7 mmHg and a standard deviation of the error of 4.0 mmHg. Our estimates show a low bias and reduced variability compared with those we have reported before.

Predictors of percutaneous endoscopic gastrostomy tube placement in patients with severe dysphagia from an acute-subacute hemispheric infarction.

This study investigated the influence of age, National Institutes of Health Stroke Scale (NIHSS) score, time from stroke onset, infarct location and volume in predicting placement of a percutaneous endoscopic gastrostomy (PEG) tube in patients with severe dysphagia from an acute-subacute hemispheric infarction. We performed a retrospective analysis of a hospital-based patient cohort to analyze the effect of the aforementioned variables on the decision of whether or not to place a PEG tube. Consecutive patients were identified using International Classification of Diseases, Ninth Revision (ICD-9) codes for acute ischemic stroke, Current Procedural Terminology (CPT)-4 codes for a formal swallowing evaluation by a speech pathologist, and procedure codes for PEG placement over a 5-year period from existing medical records at our institution. Only patients with severe dysphagia were enrolled. A total of 77 patients met inclusion criteria; 20 of them underwent PEG placement. The relationship between age (dichotomized; < and ≥75 years), time from stroke onset (days), NIHSS score, acute infarct lesion volume (dichotomized; < and ≥100 cc), and infarct location (ie, insula, anterior insula, periventricular white matter, inferior frontal gyrus, motor cortex, or bilateral hemispheres) with PEG tube placement were analyzed using logistic regression analysis. In univariate analysis, NIHSS score (P = .005), lesion volume (P = .022), and presence of bihemispheric infarction (P = .005) were found to be the main predictors of interest. After multivariate adjustment, only NIHSS score (odds ratio [OR], 1.15; 90% confidence interval [CI], 1.02-1.29; P = .04) and presence of bihemispheric infarcts (OR, 4.67; 90% CI, 1.58-13.75; P = .018) remained significant. Our data indicates that baseline NIHSS score and the presence of bihemispheric infarcts predict PEG placement during hospitalization from an acute-subacute hemispheric infarction in patients with severe dysphagia. These results require further validation in future studies.