Management of hypertensive emergencies: implications for the critical care nurse

Hypertensive emergencies are characterized by acute blood pressure elevations and potential for end organ damage. The critical care nurse must understand the pathophysiology to appreciate the therapeutic management and complications associated with the devastating clinical event. Stroke, renal damage and failure, retinopathy, aortic dissection, and encephalopathy are among the sequelae of severe hypertensive episodes. Intravenous medications are the treatment of choice to lower the blood pressure without risking hypoperfusion of the brain and other vital organs.     

A systematic review of nicardipine vs labetalol for the management of hypertensive crises

Hypertensive emergencies are acute elevations in blood pressure (BP) that occur in the presence of progressive end-organ damage. Hypertensive urgencies, defined as elevated BP without acute end-organ damage, can often be treated with oral agents, whereas hypertensive emergencies are best treated with intravenous titratable agents. However, a lack of head-to-head studies has made it difficult to establish which intravenous drug is most effective in treating hypertensive crises. This systematic review presents a synthesis of published studies that compare the antihypertensive agents nicardipine and labetalol in patients experiencing acute hypertensive crises. A MEDLINE search was conducted using the term "labetalol AND nicardipine AND hypertension." Conference abstracts were searched manually. Ultimately, 10 studies were included, encompassing patients with hypertensive crises across an array of indications and practice environments (stroke, the emergency department, critical care, surgery, pediatrics, and pregnancy). The results of this systematic review show comparable efficacy and safety for nicardipine and labetalol, although nicardipine appears to provide more predictable and consistent BP control than labetalol.     

Current concepts in the management of hypertensive crisis: emergencies and urgencies

Hypertensive emergencies and hypertensive urgencies represent a large percentage of major medical emergencies and have the potential of producing serious organ damage or death if not treated promptly and selectively. Several classifications of antihypertensive agents are discussed, with emphasis on selecting agents appropriate for patients' hypertension manifestations and comorbid situations. Epidemiology and evaluation of hypertension, as well as common pharmacokinetics of several common and new oral and parenteral antihypertensive agents, are described. Special nursing considerations of medication administration and gerontology concepts are included.     

Clinical overview of hypertensive crisis in children

Hypertensive emergencies and hypertensive urgencies in children are uncommonly encountered in the pediatric emergency department and intensive care units, but the diseases are potentially a life-threatening medical emergency. In comparison with adults, hypertension in children is mostly asymptomatic and most have no history of hypertension. Additionally, measuring accurate blood pressure values in younger children is not easy. This article reviews current concepts in pediatric patients with severe hypertension.     

Hypertensive emergencies

Hypertensive emergencies require prompt and aggressive treatment to prevent target organ damage and death. A variety of neurologic, cardiac, renal and other conditions may underlie a hypertensive crisis. A number of highly effective drugs are now available to treat hypertensive crises, including well-known agents like sodium nitroprusside and diazoxide, as well as newer drugs such as nifedipine and captopril. Some older medications have been superseded by newer agents.     

Management of hypertensive crises

Hypertensive emergencies are life-threatening conditions because their course is complicated with acute target organ damage. They can present with neurological, renal, cardiovascular, microangiopathic hemolytic anemia, and obstetric complications. After diagnosis, they require the immediate reduction of blood pressure (in <1 hour) with intravenous drugs such as sodium nitroprusside, administered in an intensive care unit. These patients present with a mean arterial pressure >140 mm Hg and grade III to IV retinopathy. Only occasionally do they have hypertensive encephalopathy, reflecting cerebral hyperperfusion, loss of autoregulation, and disruption of the blood-brain barrier. In hypertensive emergencies, blood pressure should be reduced about 10% during the first hour and another 15% gradually over the next 2 to 3 hours to prevent cerebral hypoperfusion. The exception to this management strategy is aortic dissection, for which the target is systolic blood pressure <120 mm Hg after 20 minutes. Oral antihypertensive therapy can usually be instituted after 6 to 12 hours of parenteral therapy. Hypertensive urgencies are severe elevations of blood pressure without evidence of acute and progressive dysfunction of target organs. They demand adequate control of blood pressure within 24 hours to several days with use of orally administered agents. The purpose of this review is to provide a rational approach to hypertensive crisis management.     

Hypertensive crisis

Hypertensive crisis is an acute emergency requiring aggressive management. Its incidence has decreased in recent years but still is prevalent in the medical community. From review of past and present treatment regimens, the following recommendations can be considered. (1) In the treatment of malignant hypertension with associated CHF, sodium nitroprusside is still an excellent agent. It has a rapid onset of action and blood pressure can be easily titrated. Nitroglycerin is also another agent that can be used in this situation. (2) In the treatment of malignant hypertension with associated aortic dissection, trimethophan camsylate is the preferred agent. An alternative choice is the combination of nitroprusside and labetalol. (3) In the treatment of malignant hypertension with associated myocardial ischemia, an excellent choice is nitroglycerin. Labetalol also should be considered in this situation. (4) In the treatment of hypertension during pregnancy, hydralazine is still a good choice. Labetalol has also been shown to be efficacious. (5) In the treatment of malignant hypertension with associated cerebral ischemia, the following drugs should be considered: nitroprusside, nitroglycerin, and labetalol. The most important attribute of these agents is that they are nonsedating and rapid in onset. (6) In the treatment of postoperative hypertension the choices best suited are labetalol, enalapril, nitroprusside, and nitroglycerin. These agents are rapid in onset and all can be administered intravenously.     

Control of hypertensive emergencies

Although uncommon, hypertensive emergencies require prompt recognition and treatment to reduce very high morbidity and mortality rates. Admission to an intensive care unit for treatment and monitoring is essential for optimal care. A Swan-Ganz catheter is often helpful in management. Intravenous nitroprusside sodium (Nipride, Nitropress) is probably the drug of choice for hypertensive emergencies other than those due to eclampsia or pheochromocytoma.     

Hypertensive encephalopathy presenting as status epilepticus in a three year old

Background

Hypertensive encephalopathy is one of the few neurologic emergencies in which prompt diagnosis and treatment can prevent permanent neurological damage. This syndrome is rarely seen in children.

Objectives

To discuss the recognition of hypertensive encephalopathy as a cause of acute neurological changes in children.

Case Report

We present the case of a 3-year-old boy who presented to the Emergency Department with seizures due to hypertensive encephalopathy. A review of the literature on the subject follows the case report.

Conclusions

Hypertensive encephalopathy is a rare cause of acute neurological changes in children that can cause permanent damage if not recognized early. This case illustrates the importance of considering this syndrome as a potential cause of neurological symptoms, especially as neuroimaging can initially be misleading.     

Nifedipine in hypertensive emergencies: A prospective study

Hypertensive emergencies usually present to the emergency department. Nifedipine was administered to 15 patients presenting to the emergency department with a diastolic blood pressure greater than 120 mm Hg with chest pain, shortness of breath, or focal neurological symptoms. Average blood pressure on entry was 215/134.9 mm Hg and decreased to 158/88 mm Hg over a two-hour period. No patient had any worsening of symptoms or suffered deleterious effects. All patients with pulmonary edema or chest pain noted prompt improvement in symptoms. One patient became hypotensive without clinical significance. Two patients failed to respond to nifedipine and were treated with nitroprusside. Nifedipine appears to be safe and effective in the management of hypertensive crises.     

Role of dual energy CT to improve diagnosis of non-traumatic abdominal vascular emergencies

Abdominal Radiology - Computed tomography angiography (CTA) is the modality of choice to evaluate abdominal vascular emergencies (AVE). CTA protocols are often complex and require acquisition of...     

Autonomy in the intensive care unit: the refusal of treatment

How to act in intensive care environments so that whatever is done for patients will be seen by them, then or in the future, to be in their own best interests is the problem presented by the need to defend patients' autonomy. Obstacles to patients' choice include abrogation of choice by doctors, the difficulties of discovering what patients actually wish for themselves, and the rapidly changing clinical circumstances typical of critical care. Many of these problems are obviated by discussing choices before emergencies arise with patients whose illnesses or planned surgery make the need for resuscitation a realistic possibility. Such discussions require careful delineation of the goals of resuscitation.     

Recent advances in the treatment of hypertensive emergencies

Clinical practice varies regarding the choice of agent to treat hypertensive emergencies. With the development of national guidelines, a standardized pharmacotherapeutic approach would be recommended on the basis of evidence in the published literature. Such an approach might decrease the variability among practitioners and institutions in the treatment of hypertensive emergencies. Each available agent to treat hypertensive emergencies possesses both positive and negative attributes. With several intravenous, short-acting, agents available, clinicians must make educated decisions about the best medication for their patients, and these decisions should be based on organ function as well as the patient's clinical presentation. The primary goal in hypertensive emergencies is to rapidly and safely reduce blood pressure to prevent further end-organ damage. Critical care nurses have an important role in the safe and effective management of these patients. The application of knowledge of treatment goals, hemodynamic monitoring, and pharmacological therapy for hypertensive emergencies can lead to the safe recovery of these critically ill patients.     

Minimally invasive therapy of otorhinolaryngologic emergencies in infants and children: Indications and limitations

Minimally invasive therapy of otorhinolaryngologic emergencies in infants and children was made possible by the development of improved paediatric endoscopes, telescopes and advances in anaesthetic and laser techniques. Functional endoscopic sinus surgery is a safe and efficacious therapy in children with orbital complications of acute sinusitis requiring surgery. Thus, external ethmoidectomy, which carries a serious risk of late complications like mucoceles, can be avoided. The most demanding emergency, however, is airway obstruction in infants and children. Historically, tracheotomy was the mainstay of treatment. Nowadays, various obstructing proliferations like haemangiomas, papillomas, cysts and granulomas are removed endoscopically. Selected cases of acquired laryngeal and tracheal stenosis may be managed with the CO₂ laser.     

Emergency psychopharmacology

A review of the literature pertinent to the emergency use of psychotropic agents is presented. Four general principles (underlying organicity, target symptoms, route of administration, and side effect profiles) governing the choice of psychotropic agent are discussed. Pharmacologic management approaches to commonly encountered behavioral emergencies, including drug-related disorders, assaultive patients, suicidal patients, agitated patients, and stuporous/withdrawn patients, are outlined.     

Acute blood pressure elevation associated with biological therapies for cancer: a focus on VEGF signaling pathway inhibitors

Introduction: Treatment with biological agents interfering with mechanisms of angiogenesis, such as vascular endothelial growth factor (VEGF) signaling pathway (VSP) inhibitors, was associated with an enhanced risk of acute and severe blood pressure (BP) increase and development of hypertensive emergencies.

Areas covered: The present article will review the scientific literature reporting hypertensive emergencies as a complication of biological treatment with VSP inhibitors. Hypertensive emergency is a life-threatening condition characterized by very high BP values (>180/110 mmHg) associated with acute organ damage. The exact mechanism of action is still incompletely clarified. Endothelial dysfunction following reduced bioavailability of nitric oxide has been hypothesized to play an important role in promoting hypertension and the occurrence of acute organ damage.

Expert opinion: Prevention, prompt recognition and treatment of hypertensive emergencies associated with treatment with VSP-inhibitors are essential to reduce the risk of adverse events. Not infrequently, the occurrence of hypertensive emergency led to VSP treatment discontinuation, with potential negative consequences on patient overall survival. The present review aims at providing detailed knowledge for the clinician regarding this specific issue, which could be of high impact in usual clinical practice, given the increasing burden of indications to treatment with biological agents targeted to the VEGF pathway.     

Pediatric emergency preparedness in the office

Pediatric office emergencies occur more commonly than is usually perceived by family physicians, and most offices are not optimally prepared to deal with these situations. Obtaining specific training in pediatric emergencies and performing mock "codes" to check office readiness can improve the proper handling of pediatric emergencies. Common airway emergencies include foreign-body aspiration and croup. Cool mist, racemic epinephrine nebulization and dexamethasone are typical treatment measures for croup. Asthma and bronchiolitis are common causes of respiratory distress. Hypovolemic shock is the most common cause of circulatory failure in children. Intraosseous access is a simple and underutilized route for vascular access in a critically ill child. Status epilepticus is the most common neurologic emergency. Avoidance of iatrogenic respiratory depression and hypotension can be optimized by taking an algorithmic approach to the use of anticonvulsant medications. Transport of patients after initial stabilization of an emergency should always be done in a manner that provides adequate safety and monitoring.     

Infant feeding practices in complex emergencies: a case study approach

The majority of deaths associated with complex emergencies are attributed to infants and children under the age of five years. Most of these deaths are related to preventable diseases such as malnutrition, diarrhea, and malaria. Infant feeding emergencies have emerged as a major factor in complex emergencies. This paper reviews the current information relative to infant feeding, and uses four case studies as educational tools for the management of infant feeding emergencies. Child mortality rates in refugee population have been linked directly to protein-energy malnutrition (PEM). Breast feeding has many advantages over all other forms of feeding for children up to the age of two years of age. These advantages are discussed in detail in this paper. In addition, the appropriate and inappropriate uses of breast-milk substitutes (BMS) are discussed. Breast feeding also may play a role in the spread of HIV infections from the mother to the infant. However, in the setting of complex emergencies in the developing world, the risk of an infant dying of malnutrition and infection when not breastfed is likely to be greater than is the risk of death due to HIV acquisition through breastfeeding. The physiology of lactation is reviewed with particular reference to the roles of prolactin, oxytocin, and the feedback inhibitor of lactation (FIL) hormone. No medications have been demonstrated to augment milk production that can be used in a practical sense in complex emergencies. Lastly, the principles promulgated by the WHO and UNHCR for the feeding of infants and children in emergencies and for milk powder distribution are summarized.     

Acute hypertensive crisis in pregnancy

Severe pre-eclampsia is a state of acute afterload increase where compensation may be total by use of the Frank-Starling mechanism and/or increased adrenergic drive, or may be uncompensated in a patient with limited or exhausted preload reserve. As such, we are presented with a diverse group of patients and antihypertensive therapy ideally should be individualized. In reality we are dealing with a complex situation because of the presence of the fetus raising concerns about direct effects on the fetus as well as on uteroplacental blood flow. This limits our choice of agents to those with extensive use in pregnancy except in complicated or resistant cases. For these reasons, hydralazine is the antihypertensive agent of choice for treatment of acute hypertensive emergencies in pregnancy. In the complicated case other agents such as sodium nitroprusside or nitroglycerin may be more appropriate and, in these cases, hemodynamic monitoring should be performed to allow not only greater safety, but also to tailor therapy to the individual hemodynamic profile.     

Nontraumatic Emergencies of Abdominal Aorta

Nontraumatic aortic emergencies are some of the most important causes of sudden death in adults. Aneurysm rupture and aortic dissection are the most frequent among these conditions, the prompt diagnosis of which markedly improves morbidity as well as mortality. Multidetector computed tomography is the imaging modality of choice in the diagnosis of acute aortic pathologies. Although magnetic resonance has been shown to have high sensitivity in aortic dissection evaluation, its use is limited in the emergency department. Conventional angiography is actually the gold standard in diagnosing most of these diseases but has been replaced by the less invasive cross-sectional imaging techniques. Imaging can depict an excellent anatomical and presurgical view of the disease, allowing rapid diagnosis and precise treatment.