Current practice of external ventricular drainage: a survey among neurosurgical departments in Germany.

BACKGROUND: There are various recommendations, but no generally accepted guidelines, to reduce the risk of external ventricular drainage (EVD)-associated infections. The primary objective of the present study was to evaluate the current practice of EVD in a European country and to set the results in perspective to published data. METHOD: A standardised questionnaire prepared by the Commission of Technical Standards and Norms of the German Society of Neurosurgery was sent to 127 neurosurgical units in Germany. RESULTS: Data were analysed from 99 out of 127 neurosurgical units which had been contacted. Overall, more than 10,000 EVD procedures appear to be performed in Germany annually. There is disagreement about the location where the EVD is inserted, and most EVDs are still inserted in the operation theatre. Most units apply subcutaneous tunnelling. Impregnated EVD catheters are used regularly in only about 20 % of units. Single-shot antibiotic prophylaxis is given in more than half of the units, while continued antibiotic prophylaxis is installed in only 15/99 units at a regular basis. There are discrepancies in the management of prolonged EVD use with regard to replacement policies. Regular cerebrospinal fluid (CSF) sampling is still performed widely. There were no statistical differences in policies with regard to academic versus non-academic units. CONCLUSIONS: This survey clearly shows that some newer recommendations drawn from published studies penetrate much slower into clinical routine, such as the use of impregnated catheters, for example. It remains unclear how different policies actually impact quality and outcome in daily routine.

Reversible occlusion (on-off) valves in shunted tumor patients.

The first commercially produced adjustable valve for shunted hydrocephalus patients was introduced by H. Portnoy and R. Schulte in 1973. This valve is still in use and known as reversible occlusion or on-off valve. The reversible occlusion valve is mainly used in conjunction with an existing shunt in patients receiving intraventricular cytostatic therapy. The valve has a simple mechanical lock that is closed by external pressure application with a single finger. The study method is a retrospective clinical series of 15 patients undergoing a total of 16 valve implantations between 2003 and 2010 was carried out, and the valve was tested in vitro. We report a high incidence of accidental occlusions leading to a loss of consciousness in five patients (33.3%). We furthermore demonstrate in vitro that accidental occlusions can occur. The reversible occlusion valve is needed in shunted tumor patients receiving intrathecal administration of cytostatica. The mechanism works as long as no external pressure compresses the valve. However, head positions pose significant risks for unintentional occlusions. We stress the importance of: (1) a position near the midline avoiding the retroauricular or occipital regions, (2) a handling training for nurses and doctors, (3) instruction of patients and relatives, and (4) removal of the device after intrathecal cytostatic treatment.

Long-term outcome after surgical treatment for space-occupying cerebellar infarction: experience in 56 patients.

BACKGROUND AND PURPOSE: Surgical management of space-occupying cerebellar infarction is still controversial. Data on long-term outcome are lacking. The objective of this study was (1) to evaluate outcome after at least 3 years poststroke in patients with space-occupying cerebellar infarction treated by ventriculostomy/extraventricular drainage (EVD) or suboccipital decompressive craniectomy (SDC), or both, and (2) to determine predicting factors for outcome. METHODS: In this retrospective single-center study 56 consecutive patients with acute space-occupying cerebellar infarction treated surgically between 1996 and 2005 were included. Baseline data included clinical findings, Glasgow Coma Scale on admission and before surgery, NIHSS on admission, mass effects on neuroimaging, and surgical treatment strategies. Modified Rankin Scale, NIHSS, and Scale for the Assessment and Rating of Ataxia were used to assess outcome. RESULTS: 39.3% of patients had died, 51.8% had a mRS < or =3, 35.7% had a mRS < or =2, 28.6% had a mRS < or =1. There were no significant differences in survival between treatment groups. In multivariate analysis age and mRS score at discharge were the most evident independent predictors for outcome. CONCLUSIONS: So far this is the largest study on long-term outcome after space-occupying cerebellar infarction. The value of different treatment strategies and prognostic factors for patient selection remain unclear and should be evaluated in larger prospective case-series or registries. To investigate the issue of preventive SDC randomized trials are needed.

Characteristics of thoracolumbar intramedullary subependymomas.

OBJECT: Thoracolumbar intraspinal subependymomas are very rare intramedullary low-grade tumors. The authors report on the clinical and morphological features of 2 cases of thoracolumbar intraspinal subependymomas and provide midterm follow-up data. METHODS: The clinical and radiological profiles of 2 patients with progressive spinal cord dysfunction due to thoracolumbar intraspinal subependymomas were retrospectively studied and compared with previously reported cases. RESULTS: Patients with intraspinal subependymomas initially presented with back pain and long-tract signs. The tumors were hyperintense on T2-weighted MR imaging, isointense on T1-weighted imaging, and noncontrast enhancing. Within 1 of the tumors, a medial septum was present on axial T2-weighted imaging. The tumors were intramedullary but grew exophytically and were amenable to gentle surgical separation from normal neural structures. Therefore, gross-total resection was feasible, and neurological outcome was good. No further adjuvant therapy was conducted. On follow-up (at 58 and 18 months, respectively), no tumor recurrence was observed. CONCLUSIONS: Symptomatic thoracolumbar intraspinal subependymomas with a distinct appearance on MR imaging are amenable to complete excision with favorable neurological outcome. In this study no tumor recurrence was observed at midterm follow-up in either patient, neither of whom underwent adjuvant therapy.

A stereotactic device for rabbits based on mandibular and cranial landmarks: technical note.

The authors have developed a stereotactic device for use in rabbits that uses the plane at the base of the mandible combined with cranial sutures as an anatomical reference. The device was developed for a study designed to evaluate catheters for infection prophylaxis, and this required the implantation of silicone catheters along a reproducible trajectory through the lateral ventricle. Cadaver and atlas studies demonstrated consistent spatial relationships between intracranial structures and the surface plane on which the animals were resting during the surgery. This plane is formed by the 2 mandibular angles and the mandibular tip. The authors developed a stainless steel stereotactic device that uses this mandibular plane as well as the coronal and sagittal sutures as spatial references. Operations were performed in 60 animals using the stereotactic device, and postmortem dissections of the animals' brains demonstrated 78.6% accuracy of the trajectory within a tolerance of deviation of 5 degrees , and 94.6% accuracy within a tolerance of 10 degrees . The accuracy of the trajectory of the last 18 consecutively operated animals was constantly within a tolerance of 5 degrees . The device can be autoclaved and, since it is relatively simple and inexpensive to build, the authors manufactured 3 identical frames and used them alternately to operate under sterile conditions. The fast and pain-free head fixation minimized anesthesia-related risks. The authors' experiences suggest that the device is suitable for ventricular punctures and, dependant on the individual requirements of accuracy, other procedures that require "approximate" stereotactic guidance especially when a series of animals need to undergo operations quickly.

Clinical review: Therapy for refractory intracranial hypertension in ischaemic stroke.

The treatment of patients with large hemispheric ischaemic stroke accompanied by massive space-occupying oedema represents one of the major unsolved problems in neurocritical care medicine. Despite maximum intensive care, the prognosis of these patients is poor, with case fatality rates as high as 80%. Therefore, the term 'malignant brain infarction' was coined. Because conservative treatment strategies to limit brain tissue shift almost consistently fail, these massive infarctions often are regarded as an untreatable disease. The introduction of decompressive surgery (hemicraniectomy) has completely changed this point of view, suggesting that mortality rates may be reduced to approximately 20%. However, critics have always argued that the reduction in mortality may be outweighed by an accompanying increase in severe disability. Due to the lack of conclusive evidence of efficacy from randomised trials, controversy over the benefit of these treatment strategies remained, leading to large regional differences in the application of this procedure. Meanwhile, data from randomised trials confirm the results of former observational studies, demonstrating that hemicraniectomy not only significantly reduces mortality but also significantly improves clinical outcome without increasing the number of completely dependent patients. Hypothermia is another promising treatment option but still needs evidence of efficacy from randomised controlled trials before it may be recommended for clinical routine use. This review gives the reader an integrated view of the current status of treatment options in massive hemispheric brain infarction, based on the available data of clinical trials, including the most recent data from randomised trials published in 2007.

Treatment and long-term outcome of patients with orbital cavernomas.

PURPOSE: To evaluate the long-term prognosis of visual function in patients with orbital cavernomas after conservative and surgical treatment. DESIGN: Interventional case series. METHODS: The authors describe the outcome of 20 patients with cavernous hemangiomas of the orbit treated in their departments between 1988 and 2003. This prospective study included five cases followed by clinical and radiologic observation and 15 cases of symptomatic tumors that were completely removed by means of a frontotemporal or by means of a transconjunctival approach. The clinical characteristics of orbital cavernomas were analyzed together with their appropriate treatment. Furthermore, the authors present the unusual case of a patient suffering from progressive visual deterioration from a cerebral cavernoma compressing the optic nerve. RESULTS: The follow-up period was between 3 and 10 years. All orbital cavernomas in the group of conservatively managed patients remained stable. The transconjunctival excision of a medially located lesion was uncomplicated. The frontotemporal approach was chosen for large tumors situated in the proximity of the orbital apex and was associated with a higher number of complications. A good overall outcome of visual function and patient satisfaction was achieved in 11 of 14 cases operated on by craniotomy. CONCLUSION: The combination of clinical signs and magnetic resonance imaging (MRI) is highly sensitive and specific for the diagnosis of orbital cavernomas. In the presence of visual deterioration clearly attributable to the tumor we recommend immediate surgery, while lesions producing solely exophthalmos can safely be followed by observation. The transcranial approach offers excellent exposure and a rewarding cosmetic result and may be considered for large lesions superior and medial to the optic nerve, especially if they involve the orbital apex.

Long-term outcome after spontaneous cerebellar haemorrhage.

We analysed the clinical and radiological findings and the long-term outcome after 49 +/- 34 months in 75 patients (42 men, aged 67 +/- 11 years) with spontaneous cerebellar haemorrhage (SCH). At the follow-up examination, 36 patients had died. Outcome was excellent [Rankin Scale (RS) score 0 + 1] in 22 survivors, 4 patients were moderately (RS score 2 + 3) and 13 patients were severely disabled (RS score 4 + 5). Prognostic factors are haematoma volume, intubation, hydrocephalus and clinical signs of brainstem involvement. Of the 28 surgically treated patients, outcome was favourable (RS score 0 - 2) in 4 patients only, 6 were severely disabled (RS score 3 - 6) and 18 patients had died. We conclude that the long-term outcome after SCH is frequently favourable. Because patients who were surgically treated had less favourable clinical and radiological findings, a good long-term outcome was rarely present in this group.

Combination of caudal myxopapillary ependymoma and dermal sinus: a single shared embryologic lesion?

A female child presenting with acute flaccid paraparesis at 18 months was found to have a dermal sinus in combination with a dermoid cyst and a myxopapillary ependymoma of the cauda equina and conus medullaris. A possible embryologic relation between these lesions is discussed.

Posttraumatic syringomyelia: volumetric phantom and patient studies using MR imaging.

The purpose of this study was to determine the volume of posttraumatic syringomyelia (PTS) based on standard MRI data acquisitions, and to compare the volumes with the neurological deficits of the patients. Firstly, phantom studies were performed using routine T1- (T1W; TR 500 ms, TE 13 ms) spin-echo (SE) images, 3D gradient-echo (GE) images and T2-weighted (T2W) turbo spin-echo (TSE) images (TR 3000 ms, TE 130 ms), in the sagittal plane. The slices were interleaved so that there was no gap. Twelve phantoms simulating a PTS were constructed and filled with fluid. Each volume was exactly measured immediately prior to filling (volumes: 3600-74,000 mm(3), mean 27,500 mm(3)). In the clinical study 32 patients with PTS were examined using the same protocol. Patients were supine and a phased-array coil was used. The phantom studies revealed measurement errors of within 35%. There were problems defining the boundaries in the small and irregular phantoms as well as in small and irregular PTS, and due to the partial-volume averaging effect. The two small irregular phantoms could only be measured on the axial images. The T2W images in the axial plane showed the best results: measurement accuracy 92%. In the clinical study all examinations were technically successful. The volumes of the PTS ranged between 200 and 19,800 mm(3); the mean volume was 4075 mm(3). Our initial results show that the volume measurement of a PTS using standard MRI sequences can help generate more objective and accurate measures of spinal cord lesions, and this may enhance the sensitivity of MRI in detecting disease progression or regression after treatment.

Serum procalcitonin in cerebral ventriculitis.

OBJECTIVES: The objective of this study was to test the hypothesis that serum procalcitonin is increased in patients with bacterial cerebral ventricular infections after the insertion of temporary external ventricular drains. PATIENTS AND METHODS: This open, prospective study included patients requiring temporary external ventricular drains for various neurologic conditions such as intracerebral hemorrhage with ventricular hemorrhage or space-occupying lesions in the posterior fossa (cerebellar infarctions or hemorrhages). Patients experiencing primary central nervous system infection or sepsis were excluded. Procalcitonin, C-reactive protein, and white blood cell count were measured daily. Cerebrospinal fluid was investigated every other day, including cerebrospinal fluid cell count, lactate, glucose, and cerebrospinal fluid culture. Results were categorized according to presence of bacterial cerebrospinal fluid infection as determined by positive cerebrospinal fluid cultures. RESULTS: A total of 34 consecutive patients were included. Procalcitonin was significantly higher (4.7 vs. 0.2 ng/mL) in patients with proven bacterial ventriculitis. Cerebrospinal fluid cell count (456 vs. 478 cells/microL) could not distinguish bacterial infection from abacterial reactions, mainly because of blood contamination of the cerebrospinal fluid. CONCLUSION: Cerebrospinal fluid of patients treated with temporary external ventricular drains is frequently characterized by blood contamination because of the insertion procedure, the underlying neurologic disorder such as ventricular hemorrhage, or the presence of an abacterial chemical ventriculitis. Thus, diagnosis of a bacterial ventricular infection requiring immediate antibiotic therapy is less certain. Serum procalcitonin adds to the diagnostic precision in bacterial ventriculitis.

Release of fatty acid amides in a patient with hemispheric stroke: a microdialysis study.

BACKGROUND: Excitotoxic insults such as stroke may induce release of fatty acid ethanolamides (FAEs), contributing to the downstream events in the ischemic cascade. We therefore studied release of FAEs such as anandamide, palmitylethanolamide (PEA), and oleylethanolamide (OEA) in the brain of a patient suffering from malignant hemispheric infarction treated with hypothermia. CASE DESCRIPTION: A patient with life-threatening hemispheric stroke was treated with moderate hypothermia (33 degrees C) that was maintained for 3 days, followed by a 3-day rewarming period. Microdialysis was applied to measure glutamate, lactate, and glycerol by using a microdialysis analyzer. FAEs were measured by microdialysis coupled with high-performance liquid chromatography/mass spectrometry. Release of neuroprotective fatty amides occurred within the first day after ischemia and reached high concentrations for all 3 substances in tissue surrounding the primary ischemic lesion: anandamide up to 42 pmol/mL, PEA up to 120 pmol/mL, and OEA up to 242 pmol/mL. There was a significant correlation with elevation of lactate as early marker for the hypoxic insult. CONCLUSIONS: This is the first report demonstrating release of FAEs in vivo during human stroke and may suggest contribution of the FAE signaling system to the pathophysiological events after ischemia.

Radiation-induced cavernous hemangiomas of the brain: a late effect predominantly in children.

INTRODUCTION: The induction of cavernomas as a consequence of brain irradiation was first suspected in 1994 and has been controversial since that time. METHODS: Between 1986 and 2000, 189 cerebral cavernomas were diagnosed in the Neurosurgical Department of the University of Heidelberg; of those patients, 5 had received prior radiation therapy. The ages of these 5 patients were compared with those of the 184 others with naturally occuring cavernomas. In an examination of 40 patients with cavernomas occurring after radiation (the 5 mentioned above, plus 35 from the literature) the age distribution was investigated, and a possible relationship between radiation dosage and latency interval to diagnosis of cavernoma was examined. RESULTS: Almost one in four of the patients under 15 years of age diagnosed with a cerebral cavernoma in the Neurosurgical Department of the University of Heidelberg had received prior radiation. In 40 patients with cavernomas and prior radiation (5 from Heidelberg, 35 from the literature), there was a clear accumulation in the age group of 10-19 years (50%). Most of those patients had received radiation in the first 10 years of life. The accumulation of cavernomas after radiation in childhood could not be explained by a greater frequency of radiation exposure in children compared to adults. In children up to 10 years of age at the time of radiation therapy, a dose of 3000 cGy and higher was followed by a shorter latency interval to incidence of cavernoma (P = 0.0018). In patients older than 10 years at the time of radiation, postradiation cavernomas only occurred when dosage was 3000 cGy or greater. CONCLUSION: These results indicate a correlation between radiation and cavernoma, particularly in children under 10 years of age at the time of radiation therapy. In adults, cavernomas after radiation rarely occur, and then only after higher radiation dosages (3000 cGy or more).

Effects of induced hypertension on intracranial pressure and flow velocities of the middle cerebral arteries in patients with large hemispheric stroke.

BACKGROUND AND PURPOSE: Our aim was to prospectively evaluate the effects of induced arterial hypertension in patients with large ischemic stroke. METHODS: A total of 47 monitoring sessions in 19 patients with acute, complete, or subtotal middle cerebral artery (MCA) territory stroke were performed. Intracranial pressure (ICP) was monitored using a parenchymal catheter. Mean arterial blood pressure (MAP), ICP, and peak mean flow velocity of the middle cerebral arteries (V(m)MCA) were continuously recorded. Patients with acute ICP crises were excluded. After obtaining baseline values, MAP was raised by an infusion of norepinephrine to reach an MAP increase of at least 10 mm Hg. After MAP had reached a peak plateau level, the norepinephrine infusion was stopped. RESULTS: Baseline MAP was 83.6+/-1.6 mm Hg and rose to 108.9+/-2.0 mm Hg after infusion of norepinephrine. ICP slightly increased from 11.6+/-0.9 mm Hg to 11.8+/-0.9 mm Hg (P<0.05). Cerebral perfusion pressure rose from baseline 72.2+/-2 mm Hg to 97+/-1 mm Hg (P<0.0001). V(m)MCA was already higher on the affected side during baseline measurements. At maximum MAP levels, V(m)MCA rose by 25.5+/-5.5 cm/s on the affected side and by 8.6+/-1.6 cm/s on the contralateral side. CONCLUSIONS: In patients with large hemispheric stroke without an acute ICP crisis, induced hypertension enhances cerebral perfusion pressure and augments the V(m)MCA(s), more so on the affected side. The ICP slightly increases; however, this is probably not clinically significant.

Cavernomas of the skull: review of the literature 1975-2000.

We describe four patients with intraosseous cavernous hemangiomas of the skull which were localized supraorbitally, parietally (two cases), and occipitally. The diameter ranged from 15 mm to 25 mm. They presented with slowly growing mass, tender to pressure, with spontaneous pain, and with freely mobile skin above the cavernoma sites. Magnetic resonance imaging (hyperintensity on T2 and isointensity with brain on T1) and CT (osteolytic lesion with erosion of the tabula externa) confirmed the plain skull films showing the honeycomb or sunburst appearance pattern. Resections and postoperative course were uneventful. In three of these cases there was coexistence with tumors (meningeoma, malignant lymphoma, and malignant melanoma); none of these constellations has been described before. Generally, cavernous hemangiomas of the skull are rare. There is one extensive review published by Barnes in 1984 regarding a period of 136 years with 123 intraosseous hemangiomas of the skull and 74 of the jaws. Unfortunately, the histological confirmation is not completely clear and some capillary hemangiomas are included. In a review of the literature since 1975, we found 103 histologically proven intraosseous cavernous hemangiomas of the skull (with our four cases included) and 22 of the jaws, which are shown in an overview with respect to their localization. The most frequent site was frontal, followed by temporal.

Cavernous hemangioma of the temporal muscle.

Intramuscular cavernous hemangiomas are often found in the brain, but they are uncommon in the muscles of the head and neck region, with the masseter being the most frequent, followed by the trapezius and sternocleidomastoideus. Such a lesion in the temporal muscle is an extremely unusual situation. A 55-year-old man presented with intermittent headaches and painless swelling of the right temple region brought on by stress and bending forward. On MRI, T1-weighted imaging with enhancement after contrast medium showed a low signal-intense, fat-free lesion restricted to the temporal muscle. T2 weighting showed a hyperintense, high fluid content, low-flow lesion. There was no progression within 2 years. No resection was performed. In planning a treatment approach, one must bear in mind that cavernous hemangiomas in the temporal muscle or other muscles of the head and neck can be clinically distinguished from the more aggressive capillary ones. Complications are extremely rare (hemorrhage or functional deficits). These cavernomas should simply be followed up and only resected in case of any problems (cosmetic, neurological deficits).

Effects of body position on intracranial pressure and cerebral perfusion in patients with large hemispheric stroke.

BACKGROUND AND PURPOSE: The purpose of this study was to prospectively evaluate the effects of body position in patients with large supratentorial stroke. METHODS: We performed 43 monitoring sessions in 18 patients with acute complete or subtotal middle cerebral artery (MCA) territory stroke. Intracranial pressure (ICP) was monitored with a parenchymal probe. Mean arterial blood pressure, ICP, and MCA peak mean flow velocity (VmMCA) were continuously recorded. Patients with acute ICP crises were excluded. After baseline values at a 0 degree supine position were attained, the backrest was elevated in 2 steps of 5 minutes each to 15 degrees and 30 degrees and then returned to 0 degree. RESULTS: Baseline mean arterial pressure was 90.0+/-1.6 mm Hg and fell to 82.7+/-1.7 mm Hg at 15 degrees and 76.1+/-1.6 mm Hg at 30 degrees backrest elevation (P<0.0001). ICP decreased from 13.0+/-0.9 to 12.0+/-0.9 mm Hg at 15 degrees and 11.4+/-0.9 mm Hg at 30 degrees backrest elevation (P<0.0001). As a result, cerebral perfusion pressure decreased from a baseline value of 77.0+/-1.8 to 70.0+/-1.8 mm Hg at 15 degrees and 64.7+/-1.7 mm Hg at 30 degrees backrest elevation (P<0.0001). VmMCA was already higher on the affected side during baseline measurements. VmMCA decreased from 72.8+/-11.3 cm/s at 0 degree to 67.2+/-9.7 cm/s at 15 degrees and 61.2+/-8.9 cm/s at 30 degrees on the affected and from 49.9+/-3.7 cm/s at 0 degree to 47.7+/-3.6 cm/s at 15 degrees and 46.2+/-2.2 cm/s at 30 degrees on the contralateral side (P<0.0001). CONCLUSIONS: In patients with large hemispheric stroke without an acute ICP crisis, cerebral perfusion pressure was maximal in the horizontal position although ICP was usually at its highest point. If adequate cerebral perfusion pressure is considered more desirable than the absolute level of ICP, the horizontal position is optimal for these patients.

Effects of hypothermia on excitatory amino acids and metabolism in stroke patients: a microdialysis study.

BACKGROUND AND PURPOSE: The objective of this study was to assess the effect of therapeutic moderate hypothermia on excitatory amino acids and metabolism by applying cerebral microdialysis in patients suffering from space-occupying middle cerebral artery infarction. METHODS: This was an open, prospective, observational study of 12 patients undergoing moderate hypothermia (33 degrees C) as rescue therapy for large, life-threatening middle cerebral artery infarction. Microdialysis probes were placed concomitantly with intracranial pressure (ICP) measuring devices in the frontal lobe of the infarcted and/or noninfarcted hemisphere. Using the CMA 600 Microdialysis Autoanalyzer, we analyzed glutamate, glycerol, pyruvate, and lactate. RESULTS: According to follow-up cranial CT scans, 3 different compartments of microdialysis measurements could be defined. First, noninfarcted brain tissue had stable dialysate concentrations but a significant effect of hypothermia on glutamate (2.6 versus 3.6 micromol/L), lactate (1.8 versus 3 mmol/L), and pyruvate (50 versus 95.8 micromol/L). Second, measurements from peri-infarct tissue had a significant effect of hypothermia on glutamate (4.8 versus 12.6 micromol/L), glycerol (58 versus 82 micromol/L), lactate (0.7 versus 1.3 mmol/L), and pyruvate (13.3 versus 36.8 micromol/L). Third, dialysate concentrations obtained from irreversibly damaged tissue were excessive for glutamate (453 micromol/L), glycerol (1187 micromol/L), lactate (12 micromol/L), and pyruvate (4 micromol/L). In this extreme compartment, no effect of hypothermia was observed. CONCLUSIONS: Cerebral microdialysis is a safe and feasible bedside method for neurochemical monitoring indicating normal brain tissue, potentially salvageable brain tissue, and irreversibly damaged areas in stroke. We could demonstrate that hypothermia decreases glutamate, glycerol, lactate, and pyruvate in the "tissue at risk" area of the infarct but not within the infarct core. Thus, future treatment strategies for life-threatening stroke should be guided by close neurochemical monitoring.

Effects of hypertonic (10%) saline in patients with raised intracranial pressure after stroke.

BACKGROUND AND PURPOSE: The aim of this study was to evaluate the effects of hypertonic saline in stroke patients with increased intracranial pressure (ICP) after conventional therapy with mannitol had failed. METHODS: Twenty-two episodes of ICP crisis occurred in 8 patients in whom the standard treatment of 200 mL of 20% mannitol was not effective. ICP crisis was defined as an increase in ICP of 20 mm Hg (n=18), pupillary abnormality (n=3), or a combination of both (n=1). The patients were treated with 75 mL of 10% saline over the course of 15 minutes. ICP, mean arterial blood pressure, and cerebral perfusion pressure were monitored for 4 hours. Blood gases, hematocrit, hemoglobin, pH, osmolarity, and electrolytes levels were measured before and 15 and 60 minutes after the start of infusion. Treatment was regarded as effective if ICP decreased >10% or the pupillary reaction had normalized. RESULTS: Treatment was effective in all 22 episodes. The maximum ICP decrease was 9.9 mm Hg 35 minutes after the start of infusion. Thereafter, ICP began to rise again. There was no constant effect on mean arterial blood pressure, whereas cerebral perfusion pressure was consistently increased. Blood osmolarity rose by 9 mmol/L and serum sodium by 5.6 mmol/L. Potassium levels, hemoglobin, hematocrit, and pH were slightly decreased. No unexpected side effects were noted. CONCLUSIONS: Infusion of 75 mL hypertonic (10%) saline decreases elevated ICP and increases cerebral perfusion pressure in stroke patients in whom mannitol had failed. The effect on the ICP and cerebral perfusion pressure reaches its maximum after the end of infusion and is seen for 4 hours.