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Cerebral Perfusion Pressure (cerebral + perfusion_pressure)
Selected AbstractsManagement of critically ill children with traumatic brain injuryPEDIATRIC ANESTHESIA, Issue 6 2008GILLES A. ORLIAGUET MD PhD Summary The management of critically ill children with traumatic brain injury (TBI) requires a precise assessment of the brain lesions but also of potentially associated extra-cranial injuries. Children with severe TBI should be treated in a pediatric trauma center, if possible. Initial assessment relies mainly upon clinical examination, trans-cranial Doppler ultrasonography and body CT scan. Neurosurgical operations are rarely necessary in these patients, except in the case of a compressive subdural or epidural hematoma. On the other hand, one of the major goals of resuscitation in these children is aimed at protecting against secondary brain insults (SBI). SBI are mainly because of systemic hypotension, hypoxia, hypercarbia, anemia and hyperglycemia. Cerebral perfusion pressure (CPP = mean arterial blood pressure , intracranial pressure: ICP) should be monitored and optimized as soon as possible, taking into account age-related differences in optimal CPP goals. Different general maneuvers must be applied in these patients early during their treatment (control of fever, avoidance of jugular venous outflow obstruction, maintenance of adequate arterial oxygenation, normocarbia, sedation,analgesia and normovolemia). In the case of increased ICP and/or decreased CPP, first-tier ICP-specific treatments may be implemented, including cerebrospinal fluid drainage, if possible, osmotic therapy and moderate hyperventilation. In the case of refractory intracranial hypertension, second-tier therapy (profound hyperventilation with PaCO2 < 35 mmHg, high-dose barbiturates, moderate hypothermia, decompressive craniectomy) may be introduced, after a new cerebral CT scan. [source] Remifentanil and the brainACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2008V. FODALE Background and aim: Remifentanil is an ultra-short-acting opioid, increasingly used today in neuroanesthesia and neurointensive care. Its characteristics make remifentanil a potentially ideal agent, but previous data have cast a shadow on this opioid, supporting potentially toxic effects on the ischemic brain. The aim of the present concise review is to survey available up-to-date information on the effects of remifentanil on the central nervous system. Method: A MEDLINE search within the past seven years for available up-to-date information on remifentanil and brain was performed. Results: Concise up-to-date information on the effects of remifentanil on the central nervous system was reported, with a particular emphasis on the following topics: cerebral metabolism, electroencephalogram, electrocorticography, motor-evoked potentials, regional cerebral blood flow, cerebral blood flow velocity, arterial hypotension and hypertension, intracranial pressure, cerebral perfusion pressure, cerebral autoregulation, cerebrovascular CO2 reactivity, cerebrospinal fluid, painful stimulation, analgesia and hyperalgesia, neuroprotection, neurotoxicity and hypothermia. Conclusion: The knowledge of the influence of remifentanil on brain functions is crucial before routine use in neuroanesthesia to improve anesthesia performance and patient safety as well as outcome. [source] Application of intensive care medicine principles in the management of the acute liver failure patientLIVER TRANSPLANTATION, Issue S2 2008David J. Kramer Key Points 1Acute liver failure is a paradigm for multiple system organ failure that develops as a consequence of sepsis. 2In the United States, systemic inflammatory response, sepsis, and septic shock are common reasons for intensive care unit admission. Intensive care management of these patients serves as a template for the management of patients with acute liver failure. 3Acute liver failure is attended by high mortality. Although intensive care results in improved survival, the key treatment is liver transplantation. Intensive care unit intervention may open a "window of opportunity" and enable successful liver transplantation in patients who are too ill at presentation. 4Intracranial hypertension complicates the course for many patients with acute liver failure. Initially, intracranial hypertension results from hyperemia, which is cerebral edema that reduces cerebral blood flow and eventuates in herniation. The precepts of neurocritical care,monitoring cerebral perfusion pressure, cerebral blood flow, and cortical activity,with rapid response to hemodynamic abnormalities, maintenance of normoxia, euglycemia, control of seizures, therapeutic hypothermia, osmotic therapy, and judicious hyperventilation are key to reducing mortality attributable to neurologic failure. Liver Transpl 14:S85,S89, 2008. © 2008 AASLD. [source] Autoregulation of the cerebral circulation during sleep in newborn lambsTHE JOURNAL OF PHYSIOLOGY, Issue 3 2005Daniel A. Grant Autoregulation is a vital protective mechanism that maintains stable cerebral blood flow as cerebral perfusion pressure changes. We contrasted cerebral autoregulation across sleep,wake states, as little is known about its effectiveness during sleep. Newborn lambs (n= 9) were instrumented to measure cerebral blood flow (flow probe on the superior sagittal sinus) and cerebral perfusion pressure, then studied during active sleep (AS), quiet sleep (QS) and quiet wakefulness (QW). We generated cerebral autoregulation curves by inflating an occluder cuff around the brachiocephalic artery thereby lowering cerebral perfusion pressure. Baseline cerebral blood flow was higher (P < 0.05) and cerebral vascular resistance lower (P < 0.05) in AS than in QW (76 ± 8% and 133 ± 15%, respectively, of the AS value, mean ±s.d.) and in QS (66 ± 11% and 158 ± 30%). The autoregulation curve in AS differed from that in QS and QW in three key respects: firstly, the plateau was elevated relative to QS and QW (P < 0.05); secondly, the lower limit of the curve (breakpoint) was higher (P < 0.05) in AS (50 mmHg) than QS (45 mmHg); and thirdly, the slope of the descending limb below the breakpoint was greater (P < 0.05) in AS than QS (56% of AS) or QW (56% of AS). Although autoregulation functions in AS, the higher breakpoint and greater slope of the descending limb may place the brain at risk for vascular compromise should hypotension occur. [source] Comparative Study of Bioartificial Liver Support and Plasma Exchange for Treatment of Pigs with Fulminant Hepatic FailureARTIFICIAL ORGANS, Issue 4 2000Yukio Kamohara Abstract: Recently, bioartificial liver (BAL) treatment was reported to provide beneficial effects for patients with fulminant hepatic failure (FHF). Some success in experimental or clinical trials has been reported; however, the evaluation of BAL efficacy remains unclear, especially in comparison with other treatments for FHF. The purpose of this study was to compare the efficacy between BAL and plasma exchange (PE) in experimentally induced FHF in pigs. Pigs undergoing hepatic devascularization (HD) were placed into the following groups: no treatment (control; n = 6), BAL treatment (BAL; n = 5), and plasma exchange (PE; n = 5). Each treatment was initiated 6 h after HD and lasted for 4 h. BAL treatment significantly improved liver functions in FHF pigs. The decrease in cerebral perfusion pressure was also significantly suppressed in the pigs with BAL, and their survival time was prolonged compared with the results in pigs with PE. The effects of BAL outperform those of PE in the treatment of experimental FHF model. [source] Re: Association of cerebral perfusion pressure with headache in women with pre-eclampsiaBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 1 2001Karel Mar No abstract is available for this article. [source] Bedside biochemical monitoring of the penumbra zone surrounding an evacuated acute subdural haematomaACTA NEUROLOGICA SCANDINAVICA, Issue 3 2003N. Ståhl We describe a penumbra zone with increased biochemical vulnerability in cerebral cortex underlying an evacuated acute subdural haematoma. Two microdialysis catheters were placed in this zone and one catheter was placed in the opposite, less injured hemisphere. The microdialysis perfusates were analysed bedside for glucose, pyruvate, lactate, glutamate, and glycerol. In the penumbra zone, but not in the opposite hemisphere, energy metabolism was seriously disturbed with signs of cell membrane degradation. During an adverse event (decrease in haemoglobin level, systemic blood pressure and cerebral perfusion pressure) the perturbation of energy metabolism increased in this zone. Energy metabolism recovered and the signs of cell membrane degradation disappeared after normalization of the physiological parameters. We use the term biochemical penumbra zone to describe an area with signs of energy failure and cell membrane degradation, which has a capacity to regain a normal metabolic pattern but also an increased vulnerability to secondary insults. [source] Rupture of the Innominate Artery from Blunt Trauma: Current Options for ManagementJOURNAL OF CARDIAC SURGERY, Issue 5 2005John D. Symbas M.D. It is frequently accompanied by major trauma to other organs. The traditional management is expeditious surgical repair. Methods: Three patients presented to the Emergency Department after motor vehicle collisions with traumatic rupture of the innominate artery from 2001 to 2003. One patient presented with an isolated innominate artery injury. The other two patients presented with multi-system trauma. All patients underwent surgical repair; however, repair was individualized in each case. Results: Diagnosis was obtained via arteriography in all patients after the admission chest radiographs suggested mediastinal injury. In the patient with isolated traumatic innominate artery rupture, urgent repair was performed. In the remaining two, the repair was intentionally delayed (hospital day 4 and 19) until they stabilized or recovered from other injuries or complications. In one of these patients, repair was delayed after an endovascular repair failed. In both patients who underwent delayed repair, mean arterial pressure was maintained at <70 mmHg with beta-blockade. All patients underwent repair without cardiopulmonary bypass and were monitored for adequate cerebral perfusion pressures by measuring the right carotid artery stump pressure. Successful repair was achieved in all the three patients without postoperative complications or mortality. Conclusions: Rupture of the innominate artery from blunt trauma is an infrequent but life-threatening injury that mandates repair. In patients with isolated injuries, prompt intervention is warranted. However, intentional delayed repair may be a practical alternative for those patients with multi-system trauma. [source] Severe traumatic brain injury: maximizing outcomesMOUNT SINAI JOURNAL OF MEDICINE: A JOURNAL OF PERSONALIZED AND TRANSLATIONAL MEDICINE, Issue 2 2009Mary E. Tang MD Abstract Severe traumatic brain injury is one of the leading causes of death and disability in the United States. The initial management of traumatic brain injury involves early resuscitation, computed tomography scanning, and surgical evacuation of mass lesions, when indicated. Recent research suggests that the prevention and treatment of secondary brain injury decrease mortality and improve outcomes. Specifically, treatment should address not only cerebral protection but also prevention of injury to other organ systems. To achieve the best outcomes, attention must be focused on optimizing blood pressure and brain tissue oxygenation, maintaining adequate cerebral perfusion pressures, and preventing seizures. In addition, maximizing good outcomes depends on proactively addressing the risk of common sequelae of brain injury, including infection, deep venous thrombosis, and inadequate nutrition. Guidelines developed for the management of severe traumatic brain injury have dramatically improved functional neurological outcomes. Mt Sinai J Med 76:119,128, 2009. © 2009 Mount Sinai School of Medicine [source] | ||||||||||