Acta neurochirurgica. Supplement
-
Acta Neurochir. Suppl. · Jan 2000
Assessment of 2-chloroadenosine treatment after experimental traumatic brain injury in the rat using arterial spin-labeled MRI: a preliminary report.
Adenosine is a putative endogenous neuroprotectant. Its action at A1 receptors mitigates excitotoxicity while action at A2 receptors increases cerebral blood flow (CBF). We hypothesized that cerebral injection of the adenosine analog, 2-chloroadenosine, would decrease swelling and increase CBF early after experimental traumatic brain injury (TBI). ⋯ In normal rats, injection of 0.3 nmole of 2-chloroadenosine did not increase CBF, but the higher dosage of 6 nmole dramatically increased hemispheric CBF by 1.5-2.0-fold. The effect of local injection of 2-chloroadenosine at a dose of 0.3 nmole after experimental TBI on Tlobs presumably represents a reduction in post-traumatic edema. This reduction in edema, along with the augmentation of CBF seen in normal rats at higher dosage (6 nmole), supports a role for adenosine in neuroprotection following TBI.
-
Acta Neurochir. Suppl. · Jan 2000
The synergistic effect of acute subdural hematoma combined with diffuse traumatic brain injury on brain edema.
It is well-documented that acute subdural hematoma (ASDH) following diffuse traumatic brain injury (dTBI) contributes to severe disability and high mortality. The objective of this study was to characterize edema formation in a model of ASDH and ASDH following dTBI. Eighteen Sprague-Dawley rats were separated into three groups: Sham operated (n = 6), ASDH (n = 6), ASDH following dTBI (n = 6). ⋯ We conclude that edema formation in ASDH is worsened by the combination of dTBI and ASDH. Furthermore a diffuse and focal injury in combination retain the features of the diffuse injury, but with increased severity. Further studies are required to elucidate the synergistic mechanisms involved in these pathological processes.
-
Acta Neurochir. Suppl. · Jan 2000
Evidence for lactate uptake after rat fluid percussion brain injury.
Traumatic brain injury (TBI) places enormous early energy demand on brain tissue to reinstate normal ionic balance. Glucose declines and lactate increases after TBI as demonstrated in clinical and lab studies, suggesting increased glycolysis. This led us to hypothesize that high extracellular fluid (ECF) lactate may be beneficial after TBI. We measured cerebral dialysate lactate and glucose, and arterial lactate and glucose, before & after rat Fluid Percussion Injury (FPI) (2.06 +/- 0.13 atm) with and without i.v. lactate infusion (100 mM x 4.5 hours) to test the hypotheses that arterial lactate determines ECF lactate. 14C-lactate autoradiography was also performed, to demonstrate whether lactate is taken up by traumatized brain. ⋯ Dialysate lactate was always significantly higher than arterial. After lactate infusion, both the dialysate and the arterial lactate were significantly increased (P < 0.0001). Dialysate lactate increased within 10 min. following FPI, with significantly higher values in the lactate infusion group (82% higher with lactate infusion after FPI). Dialysate glucose fell following FPI, with a more severe decline in the saline group (129% lower), suggesting lactate infusion preserves or "spares" glucose in ECF. In our autoradiographic study, i.v. 14C-lactate accumulated at the injury site, with levels 2-4 times higher than in contralateral cortex. In conclusion, arterial lactate augmentation thus increases brain dialysate lactate and results in less reduction in ECF glucose, after FPI. Infused lactate accumulates at the injury site, where metabolism is probably the greatest.
-
Acta Neurochir. Suppl. · Jan 1999
ReviewIntracranial aneurysms and subarachnoid hemorrhage management of the poor grade patient.
Between 20 and 30% of patients who suffer cerebral aneurysm rupture are in poor clinical grade when first evaluated. Management of these patients is controversial and challenging but can be successful with an aggressive proactive approach that begins with in the field resuscitation and continues through rehabilitation. In this article we review the epidemiology, pathology and pathophysiology, clinical features, evaluation, surgical and endovascular management, critical care, cost, and outcome prediction of patients in poor clinical grade after subarachnoid hemorrhage.
-
Acta Neurochir. Suppl. · Jan 1999
ReviewA combined transorbital-transclinoid and transsylvian approach to carotid-ophthalmic aneurysms without retraction of the brain.
A series of 138 patients with 143 carotid-ophthalmic aneurysms (COAs) have been treated by direct surgical approach over the past 15 years. In 5 cases the COAs were bilateral and in 15 cases either one or more aneurysms were associated with a COA. Of the 143 COAs, 87 were small, 41 large and 15 were giant. ⋯ The latter approach provides ample space for proximal and distal control of the internal carotid artery (ICA) and makes it possible to deal with demanding large/giant COAs safely. In the series presented, there was no case of premature rupture of the aneurysm. Moreover, since we started using the described approach to COAs, retraction of the brain has not been necessary, regardless of the size of the aneurysm.