The effect of furosemide on intracranial pressure and hemorrhage in preterm rabbits

1989 ◽  
Vol 70 (5) ◽  
pp. 785-792 ◽  
Author(s):  
Antonio V. Lorenzo ◽  
Clarence S. Greene ◽  
Gregory W. Hornig ◽  
L. Manuel Zavala ◽  
Keasley Welch
Keyword(s):  
Blood Pressure ◽  
Intracranial Hypotension ◽  
Intraventricular Hemorrhage ◽  
Fluid Loss ◽  
Tissue Pressure ◽  
Germinal Matrix ◽  
Content Type ◽  
Muscle Water ◽  
The Brain ◽  
Fine Print

✓ The hypothesis that intracranial hypotension due to excessive postnatal fluid loss places the premature infant at risk for germinal matrix and intraventricular hemorrhage (GM-IVH) was tested in preterm rabbits delivered at 28 and 29 days of gestation (term 32 days). Furosemide administered to newborn pups induced a diuresis that resulted in a 11% to 22% loss in body weight and a concomitant decline in muscle water (13% to 16%) and sodium (18% to 21%). Paradoxically, no change occurred in the water or electrolyte content of the brain even though cerebrospinal fluid and brain tissue pressure, but not blood pressure, declined. These changes were absent in littermates treated with saline. Microscopic examination of brain sections revealed a greater incidence of intracranial hemorrhage, particularly in the germinal matrix and choroid plexus, in furosemide-treated than in saline-treated preterm rabbit pups. These results are consistent with the hypothesis that intracranial hypotension promotes the incidence of GH-IVH in preterm animals.

The role of intracranial hypotension in neonatal intraventricular hemorrhage

1983 ◽  
Vol 58 (2) ◽  
pp. 204-209 ◽  
Author(s):  
E. Scott Conner ◽  
Antonio V. Lorenzo ◽  
Keasley Welch ◽  
Brent Dorval
Keyword(s):  
Preterm Infants ◽  
Premature Infants ◽  
Intracranial Hypotension ◽  
Intraventricular Hemorrhage ◽  
Rabbit Model ◽  
Germinal Matrix ◽  
Content Type ◽  
Ventricular Hemorrhage ◽  
Fine Print

✓ Most preterm infants develop transient intracranial hypotension, which reaches its lowest level on the 2nd day of life. This corresponds to the time when most neonatal intraventricular hemorrhage (IVH) occurs. In order to test the hypothesis that intracranial hypotension may have an etiological role in the development of IVH in premature infants, the authors induced intracranial hypotension in the preterm rabbit by the intraperitoneal injection of glycerol. The rabbit model is well suited for this study because this animal is at risk of developing spontaneous germinal matrix and ventricular hemorrhage. Compared to control littermates, the glycerol-treated animals exhibited a greater than 3.5-fold incidence of germinal matrix and intraventricular hemorrhage.

Focal brain edema associated with acute arterial hypertension

1986 ◽  
Vol 64 (4) ◽  
pp. 643-649 ◽  
Author(s):  
Shizuo Hatashita ◽  
Julian T. Hoff ◽  
Shozo Ishii
Keyword(s):  
Blood Pressure ◽  
Arterial Hypertension ◽  
Water Content ◽  
Brain Edema ◽  
Evans Blue ◽  
Blue Dye ◽  
Boundary Zone ◽  
Tissue Pressure ◽  
Content Type ◽  
Fine Print

✓ Acute arterial hypertension was studied in normal cats to determine its role in the formation of brain edema. Arterial hypertension was induced for 30 minutes by inflation of a balloon catheter situated in the descending aorta. Cerebral edema was evaluated by gross and microscopic observations, tissue water content by wet/dry weights, and blood-brain barrier (BBB) permeability by extravasation of horseradish peroxidase (HRP) and Evans blue dye. For 1 hour after the hypertensive insult, tissue pressure and regional cerebral blood flow (rCBF) were measured from the arterial boundary zone and from a non-boundary region, and intracranial pressure was recorded from the lateral ventricle as ventricular fluid pressure. Focal lesions with increased BBB permeability to Evans blue dye or HRP were usually located symmetrically in the cortex, corresponding to the occipitoparietal parts of the arterial boundary zones. The increase in water content was found only in areas of increased permeability. Tissue pressure increased simultaneously with the abrupt rise in blood pressure, and an increase in rCBF paralleled the elevation of blood pressure. Tissue pressure and rCBF returned to a steady state when blood pressure returned to normal. There were no differences in tissue pressure or rCBF between the arterial boundary zone and the non-boundary zone, even during arterial hypertension. In cerebral hemispheres examined 48 hours after the hypertensive challenge, brain edema had not continued to develop. The data indicate that acute arterial hypertension may produce focal brain edema with increased permeability of the BBB in the cortex of normal brain, particularly in the arterial boundary zones. The authors postulate that increased cerebral blood volume, high intraluminal pressure, and breakthrough of autoregulation play an important role in the formation of hypertensive brain edema.

Spontaneous germinal matrix and intraventricular hemorrhage in prematurely born rabbits

1982 ◽  
Vol 56 (3) ◽  
pp. 404-410 ◽  
Author(s):  
Antonio V. Lorenzo ◽  
Keasley Welch ◽  
Scott Conner
Keyword(s):  
Intraventricular Hemorrhage ◽  
Internal Carotid ◽  
Germinal Matrix ◽  
Content Type ◽  
Vertebral Arteries ◽  
Rete Mirabile ◽  
Premature Babies ◽  
Near Term ◽  
The Brain ◽  
Carotid And Vertebral Arteries

✓ Spontaneous hemorrhage into the ventricles in premature babies is a major problem, and neither its cause nor its pathogenesis is understood. A model is presented for the study of germinal matrix and intraventricular hemorrhage in the preterm rabbit. This animal is particularly suitable because like the human, 1) the maximal growth of the brain occurs perinatally; 2) there is an abundant germinal matrix near term, and by birth this is substantially reduced; 3) there is no rete mirabile; 4) the blood flow to the brain is via internal carotid and vertebral arteries; 5) the maturation of the lungs is completed just before term; and 6) the rabbit pup can maintain a separate existence from the dam when delivered prematurely. Eight of 64 such animals were found to have developed spontaneous germinal matrix hemorrhage with or without rupture into the ventricles. Several physiological and chemical features characteristic of the premature rabbit are presented. The hemorrhage in the lagomorph might be a paradigm of that in infants, and its study may aid in the understanding of the pathogenesis of the process.

Beagle puppy model of intraventricular hemorrhage

1982 ◽  
Vol 57 (2) ◽  
pp. 219-223 ◽  
Author(s):  
Laura R. Ment ◽  
William B. Stewart ◽  
Charles C. Duncan ◽  
Richard Lambrecht
Keyword(s):  
Blood Flow ◽  
Intraventricular Hemorrhage ◽  
Relative Volume ◽  
Low Flow ◽  
Flow Area ◽  
Germinal Matrix ◽  
Content Type ◽  
Carbon 14 ◽  
Neurological Problem ◽  
Fine Print

✓ Intraventricular hemorrhage (IVH) is a major neurological problem of the preterm infant and originates in the germinal matrix tissues of the developing brain. The newborn beagle pup has been demonstrated to provide an excellent model for this neonatal neuropathological condition. By the production of hemorrhagic hypotension followed by relative volume reexpansion, such hemorrhages can be produced in this animal. Carbon-14(14C)-iodoantipyrine was used for measuring the cerebral blood flow in this experimental model and demonstrated that, although the germinal matrix is a relatively low-flow area in the newborn beagle pup, the selective flow to this region increases significantly in animals with IVH.

Changes in extracellular potassium concentration in cortex and brain stem during the acute phase of experimental closed head injury

1981 ◽  
Vol 55 (5) ◽  
pp. 708-717 ◽  
Author(s):  
Hiroshi Takahashi ◽  
Shinya Manaka ◽  
Keiji Sano
Keyword(s):  
Blood Pressure ◽  
Brain Stem ◽  
Low Voltage ◽  
Potassium Concentration ◽  
Control Level ◽  
Extracellular Potassium ◽  
Content Type ◽  
The Impact ◽  
The Brain ◽  
Fine Print

✓ A high potassium concentration ([K+]o) in brain tissue impedes neuronal activity, as observed in spreading cortical depression. Experimental studies were performed on mice and rats to determine the role of changes of [K+]o in cerebral concussion. In the first experiment, a 600 gm-cm impact was delivered to the vertex of the mouse skull. This impact induced arrest of spontaneous movement for 465 ± 55.9 seconds (mean ± SD), accompanied by apnea, bradycardia, and low-voltage electroencephalographic recordings (EEG). The injury was also frequently followed immediately by epilepsy. This impact induced an increase of cortical [K+]o from the control level of 4.1 ± 1.8 mM to 20–30 mM, with gradual recovery within 30 minutes to the control level. In the second experiment, an impact of 9000 gm-cm was delivered to the midline parieto-occipital area of the rat and produced concussion-like phenomena similar to those elicited in mice. This level of trauma induced a significant increase of cortical [K+]o from the control level of 4.2 ± 0.8 mM to 20–50 mM in all of the rats, and also a significant increase of brain-stem [K+]o from 3.9 ± 0.6 to 20–30 mM in 73% of the rats. In these latter rats, the impact also induced apnea and a transient elevation of blood pressure, and resulted in low-voltage EEG recordings. In 23% of the rats in which [K+]o changes in the brain stem were not significant, the impact caused a transient reduction of blood pressure. The present study disclosed that an increase of [K+]o in the cerebral cortex and also in the brain stem is an important element in the phenomenon of concussion.

A model of focal cortical contusion in gerbils

1982 ◽  
Vol 57 (2) ◽  
pp. 203-209 ◽  
Author(s):  
Alan Crockard ◽  
Joon Kang ◽  
Graeme Ladds
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Surrounding Tissue ◽  
Content Type ◽  
Time Period ◽  
Cortical Contusion ◽  
Capillary Bed ◽  
The Brain ◽  
Fine Print

✓ An experimental model of focal laceration and contusion in gerbils is described. Associated with this injury are systemic changes which are neurogenically mediated and result in an immediate reduction in blood pressure, bradycardia, and generalized reduction in cerebral blood flow. There is generalized edema, as judged by a decreased specific gravity in the brain, probably related to reduced blood flow; superimposed on this, there is an edema gradient which is maximal close to the injury. This, in turn, affects the local capillary bed and prevents any local increase in flow. A separate group studied over a longer time period (6 hours) did not reveal egress of Evans blue into the surrounding tissue and this is in contrast to reports from cold-injury studies.

Delayed hemorrhage following resection of an arteriovenous malformation in the brain

2003 ◽  
Vol 99 (6) ◽  
pp. 967-971 ◽  
Author(s):  
Michael K. morgan ◽  
Mark Winder ◽  
Nicholas S. Little ◽  
Simon Finfer ◽  
Elizabeth Ritson
Keyword(s):  
Blood Pressure ◽  
Mortality Rate ◽  
Morbidity Rate ◽  
Content Type ◽  
Delayed Hemorrhage ◽  
Martin Grade ◽  
Permanent Morbidity ◽  
The Brain ◽  
Grade Iii ◽  
Fine Print

Object. Between 1989 and 2002 the authors treated 416 cases of angiographically confirmed arteriovenous malformations (AVMs) of the brain. Methods. Three hundred fifty-five patients underwent resection of an AVM; 2% died and 12% experienced a permanent morbidity (1.7% experienced a deterioration of modified Rankin Scale [mRS] score of 3–5). Patient outcomes in this series were based on the Spetzler—Martin grade. For patients with Grade I and II AVMs the rate of permanent morbidity was 1% and the rate of mortality was 0.5%. For patients with Grade III AVMs the morbidity rate was 18.9% (2.7% experienced a deterioration of mRS score of 3–5) and the mortality rate was 2.7%. For patients with Grade IV and V AVMs the morbidity rate was 25.6% (5.1% experienced a deterioration of mRS score of 3–5) and the mortality rate was 7.7%. No patient with a Spetzler—Martin Grade I or II lesion had a worsened outcome due to delayed hemorrhage, whereas 3.6% of patients with a Grade III and 12.8% of patients with Grade IV and V AVMs experienced delayed hemorrhage that led to a permanent downgrade in function. With the introduction of an aggressive postoperative blood pressure protocol (for AVMs with grades > II and sizes > 3.5 cm in diameter) the incidence of delayed postoperative hemorrhage leading to mortality or permanent morbidity decreased from 4.4 to 1%. This difference was significant. Neither case selection nor complications other than delayed hemorrhage changed between these two periods. Conclusions. In selected cases an aggressive postoperative blood pressure protocol is likely to reduce delayed hemorrhage following AVM resection.

Vasculature to the germinal matrix in rabbit pups

1986 ◽  
Vol 64 (4) ◽  
pp. 650-656 ◽  
Author(s):  
Edwin G. Fischer ◽  
Antonio V. Lorenzo ◽  
William J. Landis ◽  
Keasley Welch ◽  
Stephen K. Ofori-Kwakye ◽  
...  
Keyword(s):  
Methyl Methacrylate ◽  
Intraventricular Hemorrhage ◽  
Rabbit Model ◽  
Cerebral Vasculature ◽  
Brain Vessels ◽  
Germinal Matrix ◽  
Content Type ◽  
Vascular Casts ◽  
A Site ◽  
The Brain

✓ The authors report a study of the cerebral vasculature of premature rabbits pertaining to the germinal matrix (GM). A pigmented silicone material (Microfil) was injected into the carotid artery of anesthetized rabbits. Methyl methacrylate vascular casts of a similar group of premature rabbits were examined by scanning electron microscopy. The GM is supplied by arteries from both the basal and convexity surfaces of the brain. Vessels could be identified as arteries or veins by their typical patterns of branching and by the characteristic impressions made on the methyl methacrylate casts by endothelial nuclei. Specific evidence of structural weaknesses in the vasculature, which could be a site of predilection for GM bleeding, was not observed. The similarities in basal ganglia vasculature between premature rabbits and humans justifies using the rabbit model to study vascular aspects of the GM and intraventricular hemorrhage.

Radiosurgery for patients with recurrent small cell lung carcinoma metastatic to the brain: outcomes and prognostic factors

2005 ◽  
Vol 102 (Special_Supplement) ◽  
pp. 247-254 ◽  
Author(s):  
Jason Sheehan ◽  
Douglas Kondziolka ◽  
John Flickinger ◽  
L. Dade Lunsford
Keyword(s):  
Lung Cancer ◽  
Brain Metastases ◽  
Lung Carcinoma ◽  
Small Cell Lung Carcinoma ◽  
Small Cell ◽  
Small Cell Lung ◽  
Cell Lung Carcinoma ◽  
Content Type ◽  
The Brain ◽  
Fine Print

Object. Lung carcinoma is the leading cause of death from cancer. More than 50% of those with small cell lung cancer develop a brain metastasis. Corticosteroid agents, radiotherapy, and resection have been the mainstays of treatment. Nonetheless, median survival for patients with small cell lung carcinoma metastasis is approximately 4 to 5 months after cranial irradiation. In this study the authors examine the efficacy of gamma knife surgery for treating recurrent small cell lung carcinoma metastases to the brain following tumor growth in patients who have previously undergone radiation therapy, and they evaluate factors affecting survival. Methods. A retrospective review of 27 patients (47 recurrent small cell lung cancer brain metastases) undergoing radiosurgery was performed. Clinical and radiographic data obtained during a 14-year treatment period were collected. Multivariate analysis was utilized to determine significant prognostic factors influencing survival. The overall median survival was 18 months after the diagnosis of brain metastases. In multivariate analysis, factors significantly affecting survival included: 1) tumor volume (p = 0.0042); 2) preoperative Karnofsky Performance Scale score (p = 0.0035); and 3) time between initial lung cancer diagnosis and development of brain metastasis (p = 0.0127). Postradiosurgical imaging of the brain metastases revealed that 62% decreased, 19% remained stable, and 19% eventually increased in size. One patient later underwent a craniotomy and tumor resection for a tumor refractory to radiosurgery and radiation therapy. In three patients new brain metastases were demonstrating on follow-up imaging. Conclusions. Stereotactic radiosurgery for recurrent small cell lung carcinoma metastases provided effective local tumor control in the majority of patients. Early detection of brain metastases, aggressive treatment of systemic disease, and a therapeutic strategy including radiosurgery can extend survival.

Relief of facial pain after combined removal of precentral and postcentral cortex

1971 ◽  
Vol 34 (4) ◽  
pp. 537-543 ◽  
Author(s):  
Richard A. Lende ◽  
Wolff M. Kirsch ◽  
Ralph Druckman
Keyword(s):  
Facial Pain ◽  
The Other ◽  
Precentral Gyrus ◽  
Nerve Section ◽  
Content Type ◽  
Burning Pain ◽  
Cortical Localization ◽  
The Brain ◽  
Fine Print ◽  
Frontal Lobotomy

✓ Cortical removals which included precentral and postcentral facial representations resulted in relief of facial pain in two patients. Because of known failures following only postcentral (SmI) ablations, these operations were designed to eliminate also the cutaneous afferent projection to the precentral gyrus (MsI) and the second somatic sensory area (SmII). In one case burning pain developed after a stroke involving the brain stem and was not improved by total fifth nerve section; prompt relief followed corticectomy and lasted until death from heart disease 20 months later. In the other case persistent steady pain that developed after fifth rhizotomy for trigeminal neuralgia proved refractory to frontal lobotomy; relief after corticectomy was immediate and has lasted 14 months. Cortical localization was established by stimulation under local anesthesia. Each removal extended up to the border of the arm representation and down to the upper border of the insula. Such a resection necessarily included SmII, and in one case responses presumably from SmII were obtained before removal. The suggestions of Biemond (1956) and Poggio and Mountcastle (1960) that SmII might be concerned with pain sensibility may be pertinent in these cases.

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