Volume 8, Number 7;  Jul 16, 2007

Patient:

Session Handout:

Readings:

<1>

Unique Identifier [PMID]: 17119920

Authors: Servillo G. Bifulco F. De Robertis E. Piazza O. Striano P. Tortora F. Striano S. Tufano R.

Institution: Medical Intensive Care Unit, Department of Surgical and Anesthesiological Sciences, Naples, Italy. servillo@unina.it

Title: Posterior reversible encephalopathy syndrome in intensive care medicine. [Review] [43 refs]

Source: Intensive Care Medicine. 33(2):230-6, 2007 Feb.

Abstract: BACKGROUND: Posterior reversible encephalopathy syndrome (PRES) is a well-recognized clinico-neuroradiological transient condition. Early recognition is of paramount importance for prompt control of blood pressure or removal of precipitating factors and treatment of epileptic seizures or status epilepticus. Delay in the diagnosis and treatment may in fact results in death or in irreversible neurological sequelae. DISCUSSION: PRES is characterized by headache, altered mental status, seizures, and visual disturbances and is associated with a number of different causes, most commonly acute hypertension, preeclampsia/eclampsia, and immunosuppressive agents. Clinical symptoms and neuroradiological findings are typically indistinguishable among the cases of PRES, regardless of underlying cause. Magnetic resonance studies typically show edema involving the white matter of cerebral posterior regions, especially parieto-occipital lobes but frontal and temporal lobes, and other encephalic structures may be involved. CONCLUSIONS: Intensivists and other physicians involved in the evaluation of patients with presumed PRES must be aware of the clinical spectrum of the associated conditions, the diagnostic modalities, and the correct treatment. [References: 43]

Publication Type: Journal Article. Review.
 

<2>

Unique Identifier [PMID]: 17192762

Authors: Gardner CJ. Lee K.

Title: Hyperperfusion syndromes: insight into the pathophysiology and treatment of hypertensive encephalopathy.

Source: Cns Spectrums. 12(1):35-42, 2007 Jan.

Abstract: Hypertensive encephalopathy is one of the manifestations of a hypertensive crisis. It is not the absolute value of the blood pressure that causes the encephalopathy, rather the presence of an abrupt rise in pressure. In terms of clinical and radiographic findings, there are many similarities among a group of entities, including hypertensive encephalopathy, eclampsia, and immunosuppressant neurotoxicity. Hyperperfusion syndromes may represent these clinical disease states that may share the same pathophysiology. Magnetic resonance imaging fluid attenuated inversion recovery sequences have recognized the prominent cortical involvement of the disease that had been previously missed on computed tomography. Studies have found cortical involvement in 94% of their patients, particularly in mild cases. Animal models demonstrate endothelial damage and enhanced pinocytosis in the cortex as reasons why edema may begin in that region of the brain. Patients diagnosed with hypertensive encephalopathy should be diagnosed and treated promptly in order to avoid further neurological complications. The mean arterial pressure should be lowered by 20% to 25% within the first hour of patient presentation, followed by further gradual reduction in blood pressure over the following 24 hours. Hypertensive emergency in acute ischemic stroke should be managed with more caution. According to the 2003 American Stroke Association treatment guidelines, for patients with ischemic stroke not eligible for thrombolytic therapy, target blood pressures are a diastolic blood pressure <120 mmHg and systolic blood pressure <220 mmHg. The systolic pressure must be <185 mmHg and diastolic pressure <110 mmHg at all times if eligible for thrombolytic therapy.

Publication Type: Journal Article.
 

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Unique Identifier [PMID]: 16258402

Authors: Striano P. Striano S. Tortora F. De Robertis E. Palumbo D. Elefante A. Servillo G.

Institution: Epilepsy Center, Department of Neurological Sciences, Federico II University, Naples, Italy. sstriano@libero.it

Title: Clinical spectrum and critical care management of Posterior Reversible Encephalopathy Syndrome (PRES).

Source: Medical Science Monitor. 11(11):CR549-53, 2005 Nov.

Abstract: BACKGROUND: Posterior Reversible Encephalopathy (PRES) is characterized by acute-onset headache, altered mental status, cortical blindness and seizures, with parietal-occipital involvement. We report all cases of PRES diagnosed in our intensive care unit during the last 4 years, and evaluate their outcome in terms of the different medical treatments used. Even if usually reversible, PRES can sometimes result in death or irreversible neurological deficit, such as chronic epilepsy. MATERIAL/METHODS: From January 2001 to January 2005, we identified 8 female patients with PRES. All patients underwent basal and follow-up brain MRI. Patients referred to Epilepsy Center (about 3000 patients) were reviewed in order to identify subjects with a clinical history of PRES. These latter were clinically re-evaluated and underwent video-EEG, MRI study and neuropsychological testing. RESULTS: Of the 8 patients, 5 had hypertensive encephalopathy during pregnancy; 2 had eclampsia during the postpartum period; 1 patient with chronic renal failure developed symptoms after immunosuppressive treatment. In all patients but 1, neurological and radiological abnormalities resolved after appropriate treatment. In addition, we found 2 patients with temporal lobe epilepsy subsequent to a previous PRES. MRI revealed cortical-subcortical malacia in the parietal-occipital regions. CONCLUSIONS: The widespread use of MRI technology has made PRES familiar to many clinicians. Although PRES is reversible when treatment is instituted, delayed diagnosis and therapy can result in chronic neurological sequelae. The relationship between hypertensive encephalopathy and chronic epilepsy needs to be confirmed by longitudinal studies. Normalization of blood pressure and treatment of seizures deserves particular attention.

Publication Type: Journal Article.
 

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Unique Identifier [PMID]: 15705136

Authors: Stott VL. Hurrell MA. Anderson TJ.

Institution: Department of General Medicine, Christchurch Hospital, Christchurch, New Zealand.

Title: Reversible posterior leukoencephalopathy syndrome: a misnomer reviewed. [Review] [33 refs]

Source: Internal Medicine Journal. 35(2):83-90, 2005 Feb.

Abstract: Reversible posterior leukoencephalopathy is a syndrome of headache, seizures and visual loss, often associated with an abrupt increase in blood pressure. Prompt diagnosis and therapy with antihypertensives, anticonvulsants, removal of any offending medication and treatment of associated disorders is essential since early treatment might prevent progression to irreversible brain damage. We present six illustrative cases presenting to Christchurch Hospital and review the condition. All were hypertensive, two were receiving immunosuppressant therapy after transplantation and one chemotherapy. Only three made a full recovery. The term reversible posterior leukoencephalopathy is a misnomer as the condition is not always reversible, is not necessarily confined to the posterior regions of the brain and can affect both white and grey matter. Magnetic resonance imaging findings of increased T2 and fluid attenuated inversion recovery signal predominantly involving the posterior regions of the cerebral hemispheres should alert the clinician to the possibility of this diagnosis. [References: 33]

Publication Type: Journal Article. Review.
 

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Unique Identifier [PMID]: 11724216

Authors: Blumenfeld JD. Laragh JH.

Institution: The Rogosin Institute and The Department of Cardiothoracic Surgery, New York Presbyterian Hospital, Weill Medical College of Cornell University, New York 10021, USA.

Title: Management of hypertensive crises: the scientific basis for treatment decisions. [Review] [81 refs]

Source: American Journal of Hypertension. 14(11 Pt 1):1154-67, 2001 Nov.

Abstract: The spectrum of disorders associated with an elevated blood pressure (BP) encompasses chronic uncomplicated hypertension and the hypertensive crises, including hypertensive urgencies and emergencies. Although these syndromes vary widely in their presentations, clinical courses, and outcomes they share pathophysiologic mechanisms and, consequently, therapeutic responses to specifically targeted antihypertensive drug types. Nevertheless, hypertensive crises are often treated with drugs which, in that setting are either unsafe or are of unsubstantiated efficacy. The purpose of this review is to examine the pathophysiology of commonly encountered hypertensive crises, including stroke, hypertensive encephalopathy, aortic dissection, acute pulmonary edema, and preeclampsia-eclampsia and to provide a rational approach to their treatment based upon relevant pathophysiologic and pharmacologic principles. Measurement of plasma renin activity (PRA) level often provides insight regarding pathophysiology and predicts efficacy of antihypertensive treatments in the individual patient. However, in hypertensive crises, drug therapy is initiated before the PRA level is known. Nevertheless, the renin-angiotensin dependence (R-type) or volume dependence (V-type) of hypertension can often be deduced by the BP response to drugs that interrupt the renin system (R-drugs) or that decrease body volume (V-drugs). Based upon these considerations, a treatment algorithm is provided to guide drug selection in patients presenting with a hypertensive crisis. [References: 81]

Publication Type: Journal Article. Review.
 

Resident Report / Department of Medicine & Grady Branch Library

Emory University School of Medicine

2007 Edition

Participating Faculty:  Carlos Del Rio MD  / Joyce Doyle MD / Lorenzo Difrancesco MD / Rachel Del Favero MD / Lewis Satterwhite  MD

Contact: Karl Woodworth