The Experts below are selected from a list of 21 Experts worldwide ranked by ideXlab platform
Michiel G H Betjes - One of the best experts on this subject based on the ideXlab platform.
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hyponatremia in Acute Brain Disease the cerebral salt wasting syndrome
European Journal of Internal Medicine, 2002Co-Authors: Michiel G H BetjesAbstract:Hyponatremia in Acute Brain Disease is a common occurrence, especially after an aneurysmal subarachnoid hemorrhage. Originally, excessive natriuresis, called cerebral salt wasting, and later the syndrome of inappropriate antidiuretic hormone secretion (SIADH), were considered to be the causes of hyponatremia. In recent years, it has become clear that most of these patients are volume-depleted and have a negative sodium balance, consistent with the original description of cerebral salt wasting. Elevated plasma concentrations of atrial or Brain natriuretic peptide have been identified as the putative natriuretic factor. Hyponatremia and volume depletion may aggravate neurological symptoms, and timely treatment with adequate replacement of water and NaCl is essential. The use of fludrocortisone to increase sodium reabsorption by the renal tubules may be an alternative approach.
Ken Nakashima - One of the best experts on this subject based on the ideXlab platform.
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qualitative comparison of carbon dioxide induced change in cerebral near infrared spectroscopy versus jugular venous oxygen saturation in adults with Acute Brain Disease
Critical Care Medicine, 1995Co-Authors: Akio Tateishi, Tsuyoshi Maekawa, Yoshiyuki Soejima, Daikai Sadamitsu, Midori Yamamoto, Mitsuji Matsushita, Ken NakashimaAbstract:Objective : To compare carbon dioxide-induced changes in cerebral oxy- and deoxyhemoglobin, measured by near-infrared spectroscopy, with those changes in jugular venous oxygen saturation in adult patients with Acute Brain Disease. Design : A prospective study. Setting : The medical and surgical intensive care unit of a university hospital. Patients : Nine patients with head trauma (n = 4), cerebrovascular Disease (n = 3), and meningitis (n = 2). A total of ten measurements were done, while Paco 2 was increased from hypocapnia toward normocapnia in the nine patients. Interventions : Arterial and jugular bulb catheterization, and intracranial pressure monitoring were performed as a part of the clinical intervention. An increase in Paco 2 was obtained by inhalation of CO 2 and, if necessary, by reducing the ventilator rate. Measurements and Main Results : In each patient, the position of the jugular bulb catheter was ascertained by skull roentgenography. Near-infrared spectroscopic values for oxy- and deoxyhemoglobin were set at zero at the beginning of the study. An increase in Paco 2 from 29 ± 1 (SEM) torr (3.9 ± 0.2 kPa) to 39 ± 2 torr (5.2 ± 0.3 kPa) was accompanied by a significant increase in jugular venous oxygen saturation from 63 ± 3% to 76 ± 3% ; a significant increase in oxyhemoglobin of 3.5 ± 0.9 μmol/L (of the Brain tissue) ; and a significant decrease in deoxyhemoglobin of 1.5 ± 0.4 μmol/L. In nine of ten measurements, the slopes of changes in oxyhemoglobin against the slopes of change in jugular venous oxygen saturation were very similar. In one patient, oxyhemoglobin changed negligibly while jugular venous oxygen saturation increased by 20%. Conclusions : Jugular venous oxygen saturation consistently demonstrates cerebrovascular responsiveness to CO 2 . The direction and magnitude of changes in cerebral oxyhemoglobin, measured by near-infrared spectroscopy, were similar to those changes in jugular venous oxygen saturation in most of our cases. Interpretation of a negligible change in oxyhemoglobin in one patient, despite an obvious increase in jugular venous oxygen saturation, requires further study comparing near-infrared spectroscopy with standard techniques.
Narendra Nathoo - One of the best experts on this subject based on the ideXlab platform.
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management of hypertensive emergencies in Acute Brain Disease evaluation of the treatment effects of intravenous nicardipine on cerebral oxygenation
Journal of Neurosurgery, 2008Co-Authors: Pradeep K Narotam, Varun Puri, John M Roberts, Charles Taylon, Yashail Vora, Narendra NathooAbstract:Object Inappropriate sudden blood pressure (BP) reductions may adversely affect cerebral perfusion. This study explores the effect of nicardipine on regional Brain tissue O2 (PbtO2) during treatment of Acute hypertensive emergencies. Methods A prospective case–control study was performed in 30 patients with neurological conditions and clinically elevated BP. All patients had a parenchymal PbtO2 and intracranial pressure bolt inserted following resuscitation. Using a critical care guide, PbtO2 was optimized. Intravenous nicardipine (5–15 mg/hour) was titrated to systolic BP 20 mm Hg. Physiological parameters—intracranial pressure, PbtO2, central venous pressure, systolic BP, diastolic BP, MABP, fraction of inspired O2, and cerebral perfusion pressure (CPP)—were compared before infusion, at 4 hours, and at 8 hours using a t-test. Results Sixty episodes of hypertension were reported in 30 patients (traumatic Brain injury ...
Akio Tateishi - One of the best experts on this subject based on the ideXlab platform.
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qualitative comparison of carbon dioxide induced change in cerebral near infrared spectroscopy versus jugular venous oxygen saturation in adults with Acute Brain Disease
Critical Care Medicine, 1995Co-Authors: Akio Tateishi, Tsuyoshi Maekawa, Yoshiyuki Soejima, Daikai Sadamitsu, Midori Yamamoto, Mitsuji Matsushita, Ken NakashimaAbstract:Objective : To compare carbon dioxide-induced changes in cerebral oxy- and deoxyhemoglobin, measured by near-infrared spectroscopy, with those changes in jugular venous oxygen saturation in adult patients with Acute Brain Disease. Design : A prospective study. Setting : The medical and surgical intensive care unit of a university hospital. Patients : Nine patients with head trauma (n = 4), cerebrovascular Disease (n = 3), and meningitis (n = 2). A total of ten measurements were done, while Paco 2 was increased from hypocapnia toward normocapnia in the nine patients. Interventions : Arterial and jugular bulb catheterization, and intracranial pressure monitoring were performed as a part of the clinical intervention. An increase in Paco 2 was obtained by inhalation of CO 2 and, if necessary, by reducing the ventilator rate. Measurements and Main Results : In each patient, the position of the jugular bulb catheter was ascertained by skull roentgenography. Near-infrared spectroscopic values for oxy- and deoxyhemoglobin were set at zero at the beginning of the study. An increase in Paco 2 from 29 ± 1 (SEM) torr (3.9 ± 0.2 kPa) to 39 ± 2 torr (5.2 ± 0.3 kPa) was accompanied by a significant increase in jugular venous oxygen saturation from 63 ± 3% to 76 ± 3% ; a significant increase in oxyhemoglobin of 3.5 ± 0.9 μmol/L (of the Brain tissue) ; and a significant decrease in deoxyhemoglobin of 1.5 ± 0.4 μmol/L. In nine of ten measurements, the slopes of changes in oxyhemoglobin against the slopes of change in jugular venous oxygen saturation were very similar. In one patient, oxyhemoglobin changed negligibly while jugular venous oxygen saturation increased by 20%. Conclusions : Jugular venous oxygen saturation consistently demonstrates cerebrovascular responsiveness to CO 2 . The direction and magnitude of changes in cerebral oxyhemoglobin, measured by near-infrared spectroscopy, were similar to those changes in jugular venous oxygen saturation in most of our cases. Interpretation of a negligible change in oxyhemoglobin in one patient, despite an obvious increase in jugular venous oxygen saturation, requires further study comparing near-infrared spectroscopy with standard techniques.
Pradeep K Narotam - One of the best experts on this subject based on the ideXlab platform.
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management of hypertensive emergencies in Acute Brain Disease evaluation of the treatment effects of intravenous nicardipine on cerebral oxygenation
Journal of Neurosurgery, 2008Co-Authors: Pradeep K Narotam, Varun Puri, John M Roberts, Charles Taylon, Yashail Vora, Narendra NathooAbstract:Object Inappropriate sudden blood pressure (BP) reductions may adversely affect cerebral perfusion. This study explores the effect of nicardipine on regional Brain tissue O2 (PbtO2) during treatment of Acute hypertensive emergencies. Methods A prospective case–control study was performed in 30 patients with neurological conditions and clinically elevated BP. All patients had a parenchymal PbtO2 and intracranial pressure bolt inserted following resuscitation. Using a critical care guide, PbtO2 was optimized. Intravenous nicardipine (5–15 mg/hour) was titrated to systolic BP 20 mm Hg. Physiological parameters—intracranial pressure, PbtO2, central venous pressure, systolic BP, diastolic BP, MABP, fraction of inspired O2, and cerebral perfusion pressure (CPP)—were compared before infusion, at 4 hours, and at 8 hours using a t-test. Results Sixty episodes of hypertension were reported in 30 patients (traumatic Brain injury ...