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Biomedical subjects

A Aschoff

Publications and source records attributed to A Aschoff.

At least 37 records · Page 2Linked to original sources
PubMed1999

Neurochemical monitoring of fatal middle cerebral artery infarction.

BACKGROUND: Microdialysis is a method for neurochemical monitoring that has been applied more frequently over the past few years in patients suffering from subarachnoid hemorrhage, acute brain injury, and stroke. It is used to study the course of extracellular molecules of low molecular weight, such as excitatory amino acids or metabolic end products. CASE DESCRIPTION: We report the case of a 43-year-old patient suffering from left hemispheric stroke with a space-occupying postischemic edema leading to a considerable mass effect on the contralateral side. For treatment of severe edema, hypothermia was initiated. The microdialysis and intracranial pressure probe were placed into the noninfarcted hemisphere. A massive increase in levels of glutamate, glycerine, and the lactate-pyruvate ratio was measured 24 hours before intracranial pressure elevation was observed and brain death occurred. CONCLUSIONS: Monitoring excitatory amino acids, glycerine as a membrane component, and lactate-pyruvate ratio as an energy marker by microdialysis is a useful tool to increase our understanding of biochemical events in secondary brain damage. For future prevention of secondary ischemia in patients with massive stroke, close neurochemical monitoring might be valuable to improve therapy, particularly in the critically ill.

Adult↗
PubMed1998

Moderate hypothermia and brain temperature in patients with severe middle cerebral artery infarction.

Elevated temperature is known to facilitate neuronal injury after ischemia. After head injury a gradient between temperature and body temperature of up to 3 degrees C higher in the brain has been reported. Hypothermia may limit some of the deleterious metabolic consequences of such increased temperature. In 20 patients who had suffered severe ischemic stroke in the middle cerebral artery (MCA) territory, intracerebral temperature combined with ICP monitoring was recorded using two different thermocouples, with epidural, and parenchymatous measurements. Mild hypothermia was induced using cooling blankets. Patients were kept at 33 degrees C core temperature for 48 to 72 hours. In all patients brain temperature exceeded body-core temperature by at least up to 1 degree C (range 1.0-2.1 degrees C). Systemic cooling was effective and sustained hypothermic (33-34 degrees C) brain temperatures. With mild hypothermia critically elevated ICP values could be controlled. 12 patients survived the hemispheric stroke with a mean Barthel index of 70. Severe side effects of hypothermia were not detected. After MCA stroke, human intracerebral temperature is higher than central body-core temperature. Mild hypothermia in the treatment of severe cerebral ischemia using cooling blankets is safe and does not lead to severe side effects. Mild hypothermia can help to control critically elevated ICP values in severe space-occupying stroke and may improve clinical outcome in these patients.

Adult↗
PubMed1998

["Paradoxical" herniation after decompressive trephining].

The intracranial space is divided into two large compartments by the tentorium. The hydrostatic pressure of spinal fluid is responsible for buoyancy of the brain within these compartments. In patients with craniectomy this equilibrium is exposed to atmospheric pressure. We report on four cases of reversible herniation after either bilateral or unilateral decompressive craniectomy performed for increased intracranial pressure (ICP) and failure of conservative ICP treatment. All four patients had survived a severe neurological disease (encephalitis, subdural haematoma, stroke) which required craniectomy to control raised ICP. All were successfully weaned from the ventilator and awake and CT scans showed no space-occupying lesion anymore. The patients showed a typical "sunken pattern" at the trepanation site. All patients developed clinical signs of transtentorial herniation (i.e. unilateral dilated pupils, deteriorated alertness, and extensor posturing) shortly after either diagnostic or presumed therapeutic lumbar puncture. One patient developed herniation a second time while in the typical 30 degrees upright position. After craniectomy, transtentorial herniation is possible even in the absence of increased ICP. It is related to a negative gradient between atmospheric and intracranial pressure, which is enhanced by changes in the CSF compartment following lumbar puncture. Lumbar puncture should be avoided if possible and, when necessary, only be performed in the head-down position. Acute therapy in these cases is quite simple; it requires flat or even head-down positioning and early cranioplasty.

Adult↗
PubMed1998

Magnetic resonance epidurography with gadolinium-DTPA.

The aim of this study was to evaluate and describe MRI epidurography as a new imaging tool. Five volunteers and one patient were investigated with MR epidurography after injection of 20 ml Gd-DPTA solution (1:250/1 ml Gd-DPTA/250 ml normal saline). Magnetic resonance epidurography is possible. With fat-suppression techniques, the contrast between Gd-DPTA solution in the epidural space and surrounding soft tissue proved adequate. Using the multiplanar capability of MRI with MR epidurography coronal and sagittal projections similar to conventional epidurography, axial slices comparable to CT epidurography can be obtained. Magnetic resonance epidurography is superior to conventional and CT epidurography. Presently, due to high costs as compared with conventional and CT epidurography, MRI is not suitable for the routine monitoring of peridural catheters, but it may have a place in the future with decreasing costs for MRI and for the evaluation of patients with spine pathology, especially in describing epidural processes.

Contrast Media↗
PubMed1998

Effects of hypertonic saline hydroxyethyl starch solution and mannitol in patients with increased intracranial pressure after stroke.

BACKGROUND AND PURPOSE: The purpose of this study was to prospectively evaluate a protocol with hypertonic saline hydroxyethyl starch (HS-HES) and mannitol in stroke patients with increased intracranial pressure (ICP). METHODS: We studied 30 episodes of ICP crisis in 9 patients. ICP crisis was defined as (1) a rise of ICP of more than 25 mm Hg (n = 22), or (2) pupillary abnormality (n=3), or (3) a combination of both (n=5). Baseline treatment was performed according to a standardized protocol. For initial treatment, the patients were randomly assigned to either infusion of 100 mL HS-HES or 40 g mannitol over 15 minutes. For repeated treatments the 2 substances were alternated. ICP, blood pressure, and cerebral perfusion pressure (CPP) were monitored over 4 hours. Blood gases, hematocrit, blood osmolarity, and sodium were measured before and 15 and 60 minutes after the start of infusion. Treatment was regarded as effective if ICP decreased >10% below baseline value or if the pupillary reaction had normalized. RESULTS: Treatment was effective in all 16 HS-HES-treated and in 10 of 14 mannitol-treated episodes. ICP decreased from baseline values in both groups, P < 0.01. The maximum ICP decrease was 11.4 mm Hg (after 25 minutes) in the HS-HES-treated group and 6.4 mm Hg (after 45 minutes) in the mannitol-treated group. There was no constant effect on CPP in the HS-HES-treated group, whereas CPP rose significantly in the mannitol-treated group. Blood osmolarity rose by 6.2 mmol/L in the mannitol-treated group and by 10.5 mmol/L in the HS-HES-treated group; sodium fell by 3.2 mmol/L in the mannitol and rose by 4.1 mmol/L in the HS-HES-treated group. CONCLUSIONS: Infusion of 40 g mannitol and 100 mL HS-HES decreases increased ICP after stroke. The maximum effect occurs after the end of infusion and is visible over 4 hours. HS-HES seems to lower ICP more effectively but does not increase CPP as much as does mannitol.

Adult↗
PubMed1998

Early hemicraniectomy in patients with complete middle cerebral artery infarction.

BACKGROUND AND PURPOSE: Malignant, space-occupying supratentorial ischemic stroke is characterized by a mortality rate of up to 80%. Several reports indicate a beneficial effect of hemicraniectomy in this situation. However, whether and when decompressive surgery is indicated in these patients is still a matter of debate. METHODS: In an open, prospective trial we performed hemicraniectomy in 63 patients with acute complete middle cerebral artery infarction. Initial clinical presentation was assessed by the Scandinavian Stroke Scale (SSS) and the Glasgow Coma Scale (GCS). All survivors were reexamined 3 months after surgical decompression, with the clinical evaluation graded according to the Rankin Scale (RS) and Barthel Index (BI). We analyzed the influence of early decompressive surgery (<24 hours after symptom onset, based on clinical status at admission and initial CT findings) versus late surgery (>24 hours after first reversible signs of herniation) on mortality, functional outcome, and the length of time of critical care therapy was needed. RESULTS: In total, 46 patients (73%) survived. Despite complete hemispheric infarction, no survivor suffered from complete hemiplegia or was permanently wheelchair bound. In patients with speech-dominant hemispheric infarction (n=11), only mild to moderate aphasia was present. The mean BI score was 65, and RS score revealed severe handicap in 13% of the patients. In 31 patients with early decompressive surgery, mortality was 16% and BI score 68.8. Early hemicraniectomy led to a significant reduction in the length of time critical care therapy was needed (7.4 versus 13.3 days, P<0.05). CONCLUSIONS: In general, the outcome of patients treated with craniectomy in severe ischemic hemispheric infarction was surprisingly good. In addition, early decompressive surgery may further improve outcome in these patients.

Adult↗
PubMed1997

Hemicraniectomy with dural augmentation in medically uncontrollable hemispheric infarction.

Surgical decompression to alleviate raised intracranial pressure has been reported repeatedly in the past decades in small series of patients. Only recently have there been indications from larger trials that surgical decompression may be beneficial in treating space-occupying hemispheric infarction. However, surgical requirements for the procedure to be effective have not yet been defined. Based on theoretical criteria, the authors operated on 43 patients with medically uncontrollable hemispheric infarctions. The craniectomies were planned to be as large as possible and performed in combination with a subtemporal decompression. Postoperative computerized tomography scans were evaluated for these criteria. The mean survival rate for the group of 43 patients was 72.1% and no surviving patient ended up in a vegetative state. The mean area of craniectomy was found to be 84.3 +/- 16.5 cm2 and the mean distance of the inferior craniectomy margin to the middle fossa was 1.8 +/- 1.3 cm. Comparison of survivors and nonsurvivors failed to show a significant difference in the size of craniectomy or the distance to the floor of the middle fossa. Compared with the reported 80% fatality rate for medically treated stroke patients, in this subgroup the outcome (72.1% survival rate) is remarkably good. The authors conclude that decompressive craniectomy is an effective treatment, able to reduce mortality, and to improve neurological outcome in patients with space-occupying cerebral infarction if the size of craniectomy is large enough. Nevertheless, there is a need for further investigation to identify patients who will benefit from surgery and predictors to optimize the timing of surgical intervention.

Journal Article↗
PubMed1997

Apoptosis: correlation of cytological changes with biochemical markers in hormone-dependent tissues.

The term apoptosis, also known as programmed cell death (PCD), is used in contrast to necrotic cell death and occurs in various tissues in many different circumstances. In spite of its rather well-defined morphological features, biochemical or physiological characteristics of apoptosis are widely divergent, depending on the cellular system and/or methods in use. Here, we have outlined the current understanding of apoptosis, strictly with regard to its characteristic morphological features, discussing the correlation between morphological changes and biochemical markers.

Apoptosis↗
PubMed1997

The clinical spectrum of shunt nephritis.

BACKGROUND: Shunt nephritis is an immune-complex-mediated glomerulonephritis (GN) associated with chronically infected ventriculoatrial shunts inserted for treatment of hydrocephalus. METHODS: Six patients aged 5-22 years with shunt nephritis are reported who have been observed between 1971 and 1994. The clinical course and long-term outcome are analysed in relation to the time of diagnosis and renal histopathology. RESULTS: The time of diagnosis of shunt nephritis ranged from 0.3 to 4.5 years after the last shunt operation. Diagnosis was delayed up to 1.5 years after the first clinical manifestations. All patients had signs of infection, i.e. recurrent fever, hepatosplenomegaly, anaemia, and cerebral symptoms. Renal manifestations consisted of haematuria (macroscopic in 3 patients), proteinuria (heavy in 5), renal insufficiency (4) and hypertension (2). Decreased C3 levels, cryoglobulins, and antinuclear factors were frequent. Cultures of blood and cerebrospinal fluid provided growth mainly of S. epidermidis. Renal biopsy revealed endocapillary GN (1), membranoproliferative GN (1) and endocapillary/extracapillary GN with crescents (2). All patients received antibiotics i.v. Complete recovery was observed in three of four patients in whom the shunt was totally removed, supported by transient external drainage of cerebrospinal fluid, and followed by placement of a ventriculoperitoneal shunt. One child with delayed diagnosis, presenting with a serum creatinine of 3.2 mg/dl, hypertension, and severe scarring on renal biopsy, rapidly progressed to irreversible ESRD within 5 months. Two patients without and only partial removal of the shunt died subsequently from sepsis. CONCLUSIONS: The renal outcome of shunt nephritis is good if early diagnosis and treatment is provided including i.v. antibiotics and total removal of the infected shunt. The possible progression to ESRD requires frequent nephrological monitoring of patients with ventriculoatrial shunts.

Adult↗
PubMed1997

Brain temperature monitoring and modulation in patients with severe MCA infarction.

BACKGROUND: Brain temperature has been measured only occasionally in humans. After head trauma, a temperature gradient in brain temperature compared with body temperature of up to 3 degrees C degrees higher in the brain has been reported. Elevated temperature facilitates neuronal injury after ischemia. At present, no information concerning changes in brain temperature after acute stroke is available. METHODS: In 15 patients who had suffered severe ischemic stroke in the MCA territory, intracerebral temperature was recorded with use of two different thermocouples, with intraventricular, epidural, and parenchymatous measurements. Body-core temperature (Foley catheter temperature) and jugular bulb temperature (n = 5) were recorded simultaneously. Measures for reducing brain temperature were compared. RESULTS: In all patients, brain temperature exceeded body-core temperature by at least up to 1 degrees C (range, 1.0 to 2.1 degrees C). Temperature in the ventricles exceeded epidural temperature by up to 2.0 degrees C. Brain temperature modulation was independent of single pharmacologic (paracetamol, metamizol) treatments. Only systemic cooling was effective and sustained hypothermic (33 to 34 degrees C) brain temperatures. CONCLUSION: After MCA stroke, human intracerebral temperature is higher than central body-core temperature. There is also a temperature gradient within the brain, with the ventricles warmer than the surface. Mild hypothermia in the treatment of severe cerebral ischemia with use of cooling blankets is both easy to perform and effective in the therapy of severe hemispheric infarction.

Adult↗
PubMed1996

[Epidural cerebrospinal fluid pressure measurement and therapy of intracranial hypertension in "malignant" middle cerebral artery infarct].

BACKGROUND AND PURPOSE: A permanent elevation of ICP after severe brain injury for instance in subarachnoid or intracerebral hemorrhage or neurotrauma is associated with a poor clinical outcome. Although increasingly being used in the intensive care of patients with elevated ICP, continuous epidural ICP monitoring in ischemic stroke has not been firmly established yet. PATIENTS AND METHODS: We prospectively evaluated the clinical course and outcome of patients with raised ICP due to space occupying ischemic middle cerebral artery (MCA) infarction as seen in CT, who underwent continuous ICP monitoring. Epidural ICPprobes were inserted ipsilaterally (all patients) and contralaterally (additional in 7 patients) to the side of infarctation. Glasgow Coma and Scandinavian Stroke Scales (GCS and SSS) were obtained initially and in the further clinical course. All patients were subjected to a standardized treatment protocol for raised ICP. ICP values were correlated with clinical presentation at the time point of deterioration, with outcome and CT findings. Effectiveness of different treatment modalities to lower ICP were analyzed and discussed. RESULTS: 9 of 48 patients survived the MCA infarct (19%), with the cause of death being transtentorial herniation with subsequent brain death in all 39 patients. Mean SSS at admission was 20.6 (survivors 21.5 +/- 5.6, nonsurvivers 19.8 +/- 6.5). All patients showed clinical signs of herniation before the increase of ICP. All 39 patients who died developed ICP values higher than 35 mmHg and no patient with ICP values of more than 35 mmHg survived. CCT changes dit not necessarily reflect the absolute measured ICP values. All treatment modalities for raised ICP including osmotherapy, controlled hyperventilation, tromethamol and barbiturates were initially effective, but only in a minority of patients ICP control could be sustained. CONCLUSIONS: We conclude that ICP monitoring in large hemispheric infarction may predict clinical outcome. ICP monitoring was not helpful in guiding long term treatment of ICP. It remains doubtful, whether ICP monitoring has a positive influence on clinical outcome of acute severe ischemic stroke.

Adult↗
PubMed1996

The diagnostic value of optic disc evaluation in acute elevated intracranial pressure.

PURPOSE: Ophthalmologists often are asked to evaluate the optic disc for evidence of acute increased intracranial pressure (ICP). The authors studied the incidence of papilledema in a population of patients with a documented acute increase in ICP. METHODS: Included in this study were 37 patients with acute elevated ICP due to a spontaneous hemorrhage or craniocerebral trauma. In all patients, the ICP was monitored continuously. Fundus examination was performed twice daily on at least 7 consecutive days. RESULTS: According to the level and duration of the ICP, the patients were divided into three groups. Group 1 included 13 patients who had a slightly elevated ICP (range, 20-30 mmHg) on at least 3 consecutive days. In this group, 3 of 13 patients demonstrated venous congestion on the fifth or sixth day. No swelling of the optic disc was seen in this group. Group 2 included seven patients with an elevated ICP, with values ranging from 30 to 70 mmHg lasting for at least 3 consecutive days. In this group, one patient had a blurred disc margin on the sixth day. Group 3 included 17 patients with shortlasting ICP values, ranging from 30 to 60 mmHg for less than 72 hour. Neither papilledema nor abnormalities of fundus vessels were seen in this group. CONCLUSION: Papilledema in acute elevation of ICP is an uncommon event. Its absence does not preclude the presence of ICP elevation.

Acute Disease↗
PubMed1996

In-situ end labelling with bromodeoxyuridine--an advanced technique for the visualization of apoptotic cells in histological specimens.

The fragmentation of nuclear DNA is considered to be a biochemical indication of programmed cell death (PCD) in various tissues. Several light microscopical approaches have been employed for the visualization of such fragmentation and have used either in-situ nick end labelling (ISEL) or in-situ nick translation (ISNT) with labelled dUTP. In the current paper, we can report a new method in which 0.5 micron Epon sections of mouse jejunum were incubated with terminal deoxynucleotidyl transferase (TdT) and 5-bromo-2-deoxyuridine (BrdU) for the in-situ tailing of fragmented DNA. Anti BrdU and the peroxidase anti peroxidase method (PAP) were used for staining the reaction product. Semithin sections of jejunum revealed high resolution images of labelled nuclei in the intestinal mucosa. An examination with confocal laser scanning microscopy indicated the differential distribution of immunoprecipitates in cellular nuclei, perhaps representing those distinct levels of DNA cleavage that may characterise the discrete stages of apoptosis. This new method is likely to offer new possibilities for the high resolution imaging of PCD, including the assessment of time courses and apoptosis statuses in histochemically characterized cells.

Animals↗
PubMed1996

The value of intracranial pressure monitoring in acute hemispheric stroke.

BACKGROUND AND PURPOSE: Persistently elevated intracranial pressure (ICP) has been associated with poor clinical outcome after severe brain injury, such as neurotrauma, intracerebral hemorrhage, and subarachnoidal hemorrhage. Although ICP monitoring is increasingly being used in intensive care treatment of patients with ischemic stroke, its value has not been established. PATIENTS AND METHODS: The clinical course of 48 patients with the clinical signs of increased ICP due to large hemispheric or middle cerebral artery territory infarction defined by CT and subjected to ICP monitoring was prospectively evaluated. Epidural ICP probes were inserted ipsilaterally to the site of primary brain injury in all and also contralaterally in seven patients. Initial clinical presentation was assessed by the Scandinavian Stroke Scale (SSS) and the Glasgow Coma Score (GCS). All patients were treated according to a standardized treatment protocol for elevated ICP. ICP values were correlated with the clinical presentation at the time point of deterioration, with outcome, and with CT findings. Different treatment strategies to lower ICP were analyzed as to their effectiveness. RESULTS: Only nine of the 48 patients survived the infarct (19%). The cause of death was transtentorial herniation with subsequent brain death in all 39 patients. The patients' mean SSS on admission was 20.6 (survivors 21.5 +/- 5.6, nonsurvivors 19.8 +/- 6.5). In all patients clinical signs of herniation preceded the increase in ICP. Patients with ICP values > 35 mm Hg did not survive. CT changes did not always correspond with the measured ICP values. All medical strategies to lower ICP, including osmotherapy, hyperventilation, THAM-buffer, and barbiturates, were initially effective, but only in a minority of patients was ICP control sustained. CONCLUSIONS: ICP monitoring of large hemispheric infarction can predict clinical outcome. Pharmacologic intervention had no sustained effect. ICP monitoring was not helpful in guiding long-term treatment of increased ICP. It remains doubtful that ICP monitoring in acute ischemic stroke has a positive influence on clinical outcome.

Acute Disease↗
PubMed1996

Coil placement after clipping: endovascular treatment of incompletely clipped cerebral aneurysms. Report of two cases.

In up to 4% of patients whose aneurysms are microsurgically clipped, there is an expected or unexpected aneurysm residuum. The authors describe two patients in whom surgical clipping did not result in complete obliteration of the aneurysm sac and in whom a second operation was not believed to be the solution to the problem. In both patients complete occlusion of the aneurysm residuum was achieved via an endovascular approach. Using the Guglielmi detachable coil system, it was possible to place two platinum coils selectively into the aneurysms. The endovascular approach may be a good treatment option for all patients in whom surgical clipping does not result in complete obliteration of the aneurysm sac and reoperation is contraindicated or unacceptable to the patient.

Adult↗