RESUMEN
BACKGROUND: The presence of osmotic gradients in the development of cerebral edema and the effectiveness of osmotherapy are well recognized. A modification of ventriculostomy catheters described in this article provides a method of osmotherapy that is not currently available. The reductive ventricular osmotherapy (RVOT) catheter removes free water from ventricular cerebrospinal fluid (CSF) by incorporating hollow fibers that remove water vapor, thereby providing osmotherapy without increasing osmotic load. OBJECTIVE: To increase osmolarity in the ventricular CSF through use of RVOT in vivo. METHODS: Twelve Yorkshire swine with contusional injury were randomized to external ventricular drainage (EVD) or RVOT for 12 hours. MR imaging was obtained. Serum, CSF, and brain ultrafiltrate were analyzed. Histology was compared using Fluor-Jade B and hematoxylin and eosin (H & E) stains. RESULTS: With RVOT, CSF osmolality increased from 292 ± 2.7 to 345 ± 8.0 mOsmol/kg (mean ± SE, P = 0.0006), and the apparent diffusion coefficient (ADC) in the injury region increased from 0.735 ± 0.047 to 1.135 ± .063 (P = 0.004) over 24 hours. With EVD controls, CSF osmolarity and ADC were not significantly changed. Histologically, all RVOT pigs showed no evidence of neuronal degeneration (Grade 1/4) compared to moderate degeneration (Grade 2.6 ± .4/4) seen in EVD treated animals (P = 0.02). The difference in intracranial pressure (ICP) by area under the curve approached significance at P = .065 by Mann Whitney test. CONCLUSION: RVOT can increase CSF osmolarity in vivo after experimental traumatic brain injury (TBI). In anticipated clinical use, only a slight increase in CSF osmolarity may be required to reduce cerebral edema.
Asunto(s)
Lesiones Encefálicas/líquido cefalorraquídeo , Lesiones Encefálicas/cirugía , Catéteres , Ventriculostomía/instrumentación , Animales , Edema Encefálico/líquido cefalorraquídeo , Edema Encefálico/prevención & control , Edema Encefálico/cirugía , Modelos Animales de Enfermedad , Concentración Osmolar , Porcinos , Ventriculostomía/métodosRESUMEN
BACKGROUND: Detection of serum monoclonal proteins is a common laboratory analysis used in the evaluation of patients with B-cell disorders. Since many individuals with elevated immunoglobulin have no symptoms, it is important to have simple methods for initial screening of patients with suspected B-cell disorders. METHODS: Samples of serum from healthy donors and from patients with elevated immunoglobulin levels were tested using a technology named Droplet MicroChromatography (DMC). DMC was developed at Artann Laboratories (West Trenton, New Jersey, USA) for the rapid assessment of changes in the composition of serum. DMC is based on the dynamics of the sediment pattern formation during drying of a fluid microdroplet. RESULTS: Results of this pilot study confirm the hypothesis that the pattern formation created by drying droplets of serum would differ between normal samples and those containing monoclonal proteins. Reproducible differences in the patterns formed by the two types of specimens are shown. Strong correlation between abnormally elevated levels of immunoglobulins in the serum of myeloma patients and the patterns formed by drying droplets of serum indicates that the DMC technique may be suitable for semi-quantitative analysis of serum samples. We also demonstrate that computer identification of the drying droplet structure and dynamics is a tractable issue. CONCLUSIONS: DMC has significant diagnostic potential and can serve as a basis for development of a simple, rapid, and inexpensive method for initial screening of patients suspected of having multiple myeloma and other pathologies of lymphoid origin that are associated with the overproduction of monoclonal immunoglobulins. The DMC test requires only approximately 1 microL of serum and could therefore be performed in any facility where it is safe to work with serum.