✓ A case is reported in which a ruptured intracerebral aneurysm had been infected by Neisseria meningitidis. Evacuation of the resulting hematoma, clipping the aneurysm and antibiotic therapy resulted in a satisfactory recovery.
George W. Sypert and Harold F. Young
Effects on plasma and CSF electrolytes and ion excretion
Alfonso Schettini, Bernard Stahurski, and Harold F. Young
✓ In 22 patients to be operated on for brain tumors or cerebral aneurysms, the effect of osmotic diuresis was compared with that of osmotic-loop diuresis on plasma and cerebrospinal fluid (CSF) electrolytes, and water and ion excretion. Mannitol or mannitol plus furosemide were used to reduce brain bulk. After treatment with thiopental and hyperventilation, patients received randomly a rapid infusion of mannitol (1.4 gm/kg), or mannitol (1.4 gm/kg) plus furosemide (0.3 mg/kg). Brain shrinkage was considerably greater and more consistent with mannitol plus furosemide than with mannitol alone. However, hyponatremia, hypokalemia, hypochloremia, and hyperosmolality were also more marked (p < 0.05) with mannitol plus furosemide than with mannitol. The rate of water and ion excretion was even more striking. At 30 minutes after absorption of mannitol alone, water excretion peaked at 17 ml/min, and gradually decreased to 3.8 ml/min 70 minutes later. With mannitol plus furosemide, during an identical time course, initial water excretion was 30 ml/min, followed by a further rise to 42 ml/min and then a decline to 17 ml/min. At peak diuresis after mannitol, Na+ and Cl− excretion averaged 0.57 and 0.62 mEq/min, respectively. This compares with mean values of 3.7 and 4.12 mEq/min for Na+ and Cl−, respectively, after mannitol plus furosemide. Although optimum brain shrinkage is achieved with osmotic-loop diuresis, the rapid electrolyte depletion (Na+ and Cl−) must be corrected to avoid altered sensorium during the patients' postoperative course.
Anthony Marmarou, Harold F. Young, and Gunes A. Aygok
The primary objective of this study was to estimate the prevalence of idiopathic normal-pressure hydrocephalus (NPH), both diagnosed and undiagnosed, among residents of assisted-living and extended-care facilities, by using a practical screening tool. A secondary objective was to evaluate prospectively the diagnosis and outcome of surgical treatment in a subset of patients residing in healthcare facilities who were at risk for idiopathic NPH.
A retrospective chart analysis was performed using the medical records from four nursing homes. The final analysis included 147 patient records. Symptomatology and comorbidity were evaluated, as was the ability to perform activities of daily living. In a subset of 17 patients residing in healthcare facilities, the authors applied a standard idiopathic NPH diagnostic and management protocol and followed up the patients 1 year after treatment.
The estimated incidence of suspected idiopathic NPH among all patients in the retrospective survey ranged from 9 to 14%, depending on the diagnostic criteria used. Among the cohort of 17 patients available for an in-hospital study and 1-year follow up, 11 received shunts and seven of these showed either transient or sustained improvement.
A valid and practical diagnostic method is needed to identify idiopathic NPH accurately before admitting patients to a healthcare facility. Data from a prospective study of 17 patients residing in healthcare facilities indicated that supplementary tests remain predictive of a positive response to shunt insertion but cannot predict whether a favorable outcome will be sustained in a population of patients who have been confined to a wheelchair for a prolonged period of time. This finding supports the notion of a finite window of opportunity for successful treatment of idiopathic NPH and the imperativeness of an early diagnosis.
John K. Vries, Donald P. Becker, and Harold F. Young
✓ A new technique for monitoring intracranial pressure is presented. It is based on a hollow screw in the skull whose tip projects through the dura into the subarachnoid space. The screw can be easily inserted under local anesthesia. Pressure is monitored isovolumetrically by connecting the screw to a transducer. The system can be calibrated in situ and has been successfully used in 56 patients during a 6-month period.
Martin H. Weiss, Harold F. Young, and Dee E. McFarland
Jason L. Schroeder, Jason M. Highsmith, Harold F. Young, and Bruce E. Mathern
Few therapies have consistently demonstrated effectiveness in preserving O2 delivery after spinal cord injury (SCI). Perfluorocarbons (PFCs) offer great promise to carry and deliver O2 more efficiently than conventional measures. The authors investigated the use of Clark-type microelectrodes to monitor spinal cord oxygenation directly (intraparenchymal [IP] recording) and indirectly (cerebrospinal fluid [CSF] recording) in the context of SCI, O2 therapy, and PFC treatment.
After placement of a subdural/CSF Licox probe in rats, incremental increases in the fraction of inspired O2 (FiO2) up to 100% were administered to establish a dose-response curve. The probe was then placed in the parenchyma of the same animals for a second dose-response curve. In a second study, rats with CSF or IP probes underwent SCI with the NYU Impactor and treatment with O2, followed by administration of PFC, or saline in the control group.
All animals in the first experiment responded to the FiO2 dose increase, with changes in PO2 evident in both CSF and IP levels. The SCI in the second experiment caused a marked drop in PO2 from a mean of 21.4 to 10.4 mm Hg, with most animals dropping to less than half their preinjury value. All animals responded to 100% O2 treatment. Every animal that received PFCs showed significant improvement, with a mean increase in PO2 of 23.3 mm Hg. Only 1 saline-treated animal showed any benefit. Oxygen values in the PFC treatment group reached up to 6 times the normal level.
Oxygen levels in SCI show a profound drop almost immediately postinjury. Administration of PFCs combined with 100% O2 therapy can reverse tissue hypoxia and holds promise for reducing ischemic injury.
Michael E. Carey, Harold F. Young, Berkley L. Rish, and Jacob L. Mathis
✓ The authors report a follow-up study of 103 American soldiers who were treated for brain wounds at one neurosurgical facility in Vietnam. The estimated mortality after evacuation from the war zone was 6% to 8%. Severe brain wounds, meningitis, and pulmonary emboli accounted for the majority of the late deaths. Thirty-four per cent had post-debridement complications such as retained bone fragments (16%), infection (15%), cerebrospinal fluid leaks or wound dehiscence (2%). Removal of retained intracerebral bone was associated with occasional complications but unquestionably prevented several late brain abscesses; only two patients in this series developed a late brain abscess. About half of those who were evacuated from Vietnam with retained intracerebral bone harbored fragments that were contaminated with bacteria.
David J. Mayer, Donald D. Price, Donald P. Becker, and Harold F. Young
✓ A sensitive quantitative index for predicting optimal electrode position in percutaneous anterolateral cordotomy was determined by electrical stimulation through the lesioning electrode. If the threshold for pain elicited by the stimulation electrode was less than 300 µA, a 5-sec radiofrequency lesion of 50 mA would produce complete contralateral analgesia with no weakness. When the pain threshold exceeded 300 µA, incomplete or no analgesia would result with the standard single lesion. The results further suggested that the fibers in the anterolateral quadrant that transmit pain are discretely rather than diffusely localized.
Philippe Gadisseux, John D. Ward, Harold F. Young, and Donald P. Becker
✓ There has been a rapid expansion of knowledge in the field of nutrition and metabolism with regard to the general surgical patient. However, only recently has there been greater appreciation of the benefits of adequate nutrition and appropriate metabolic care of the neurosurgical patient. In this review, the authors attempt to outline 1) the metabolic response to stress in general, and how it applies to the neurosurgical patient; 2) how best to provide adequate nutritional support for the neurosurgical patient; 3) the effects of nutrition on neurotransmitters; and 4) the effect of diet and nutrition on patients with malignant brain tumors.