The management of acute hypertension in patients with renal dysfunction: labetalol or nicardipine?

Safety and efficacy of continuous intravenous labetalol for blood pressure control in neurosurgical patients

OBJECTIVES

Current evidence supporting the use of continuous intravenous labetalol for blood pressure (BP) control in neurosurgical patients is limited. This study aims to assess the efficacy and safety of labetalol in neurosurgical patients and identify potential contributing factors to these outcomes.

METHODS

We retrospectively reviewed the medical records of neurosurgical patients who received continuous labetalol infusion for BP control. Efficacy was assessed based on the time needed to achieve the target BP (systolic BP ≤ 140 mmHg or diastolic BP ≤ 90 mmHg). Safety was assessed according to adverse events that occurred during labetalol administration. Factors associated with efficacy and safety were analyzed using a logistic regression model.

RESULTS

Among 79 patients enrolled in this study, 47 (59.49%) achieved the target BP within 1 hour (early response). No factors were significantly associated with an early response. Hypotension was observed in 11 patients (13.9%), and bradycardia was observed in 8 patients (10.1%). Hypotension was significantly associated with patient age and motor impairment, while bradycardia was significantly associated with diabetes mellitus.

CONCLUSION

The efficacy and safety profiles of labetalol infusion suggest this treatment as a promising option for BP control in neurosurgical patients.

Hypertensive crisis: diagnosis, presentation, and treatment

PURPOSE OF REVIEW

Hypertensive crisis (HTN-C) is a condition of increasing prevalence. It carries significant morbidity and mortality, and prompt recognition and treatment are crucial. There is a paucity of controlled trials, so a working knowledge of the most recent literature in the area of HTN-C is helpful.

RECENT FINDINGS

Novel serological markers, including serum corin, have been found to aid in the early identification of end-organ damage from severely elevated blood pressure (BP). In the area of BP following thrombolysis for ischemic stroke, lower target BP (130-140 mmHg) is associated with some improved outcomes. Two large trials of lower BP following mechanical thrombectomy in stroke have failed to show improved outcomes; however, observed data show benefits at lower than currently recommended levels. Clevidipine, a calcium channel blocker marketed for unique use in HTN-C, was found to be noninferior to the generic less expensive nicardipine. Oral nifedipine was found to be the most effective agent for sustained BP reduction in preeclampsia.

SUMMARY

HTN-C remains an area with few prospective randomized trials, but there is active research on identifying lower goals for specific clinical scenarios. Ideal therapeutic agents should be tailored for specific end-organ damage.

Effect of Blood Pressure Variability on Outcomes in Emergency Patients with Intracranial Hemorrhage

Introduction

Patients with spontaneous intracranial hemorrhage (sICH) have high mortality and morbidity, which are associated with blood pressure variability. Additionally, blood pressure variability is associated with acute kidney injury (AKI) in critically ill patients, but its association with sICH patients in emergency departments (ED) is unclear. Our study investigated the association between blood pressure variability in the ED and the risk of developing AKI during sICH patients’ hospital stay.

Methods

We retrospectively analyzed patients with sICH, including those with subarachnoid and intraparenchymal hemorrhage, who were admitted from any ED and who received an external ventricular drain at our academic center. Patients were identified by the International Classification of Diseases, Ninth Revision (ICD-9). Outcomes were the development of AKI, mortality, and being discharged home. We performed multivariable logistic regressions to measure the association of clinical factors and interventions with outcomes.

Results

We analyzed the records of 259 patients: 71 (27%) patients developed AKI, and 59 (23%) patients died. Mean age (± standard deviation [SD]) was 58 (14) years, and 150 (58%) were female. Patients with AKI had significantly higher blood pressure variability than patients without AKI. Each millimeter of mercury increment in one component of blood pressure variability, SD in systolic blood pressure (SBP_SD), was significantly associated with 2% increased likelihood of developing AKI (odds ratio [OR] 1.02, 95% confidence interval [CI], 1.005–1.03, p = 0.007). Initiating nicardipine infusion in the ED (OR 0.35, 95% CI, 0.15–0.77, p = 0.01) was associated with lower odds of in-hospital mortality. No ED interventions or blood pressure variability components were associated with patients’ likelihood to be discharged home.

Conclusion

Our study suggests that greater SBP_SD during patients’ ED stay is associated with higher likelihood of AKI, while starting nicardipine infusion is associated with lower odds of in-hospital mortality. Further studies about interventions and outcomes of patients with sICH in the ED are needed to confirm our observations.

Calcium Channel Blockers in Acute Care: The Links and Missing Links Between Hemodynamic Effects and Outcome Evidence

Calcium channel blockers (CCBs) exert profound hemodynamic effects via blockage of calcium flux through voltage-gated calcium channels. CCBs are widely used in acute care to treat concerning, debilitating, or life-threatening hemodynamic changes in many patients. The overall literature suggests that, for systemic hemodynamics, although CCBs decrease blood pressure, they normally increase cardiac output; for regional hemodynamics, although they impair pressure autoregulation, they normally increase organ blood flow and tissue oxygenation. In acute care, CCBs exert therapeutic efficacy or improve outcomes in patients with aneurysmal subarachnoid hemorrhage, acute myocardial infarction and unstable angina, hypertensive crisis, perioperative hypertension, and atrial tachyarrhythmia. However, despite the clear links, there are missing links between the known hemodynamic effects and the reported outcome evidence, suggesting that further studies are needed for clarification. In this narrative review, we aim to discuss the hemodynamic effects and outcome evidence for CCBs, the links and missing links between these two domains, and the directions that merit future investigations.

An Updated Review of Hypertensive Emergencies and Urgencies

A hypertensive crisis is an abrupt and severe rise in the arterial blood pressure (BP) occurring either in patients with known essential or secondary hypertension, or it may develop spontaneously. The most frequent cause for the severe and sudden increase in BP is inadequate dosing or stopping antihypertensive treatment in hypertensive patients. Severe hypertension can be defined as either a hypertensive emergency or an urgency, depending on the existence of organ damage. In hypertensive urgencies, there are no signs of acute end-organ damage, and orally administered drugs might be sufficient. In hypertensive emergencies, signs of acute end-organ damage are present, and in these cases, quickly-acting parenteral drugs must be used. The prompt recognition, assessment, and treatment of hypertensive urgencies and emergencies can decrease target organ damage and mortality. In this review, the definitions and therapeutic recommendations in a hypertensive crisis are presented in the light of the 2017 ACC/AHA Hypertension Guidelines.

Hypertensive crisis in children: an experience in a single tertiary care center in Korea

BACKGROUND

Hypertensive crisis is a medical emergency that can cause acute damage to multiple end-organs. However, relatively little is known on the etiology, treatment, and outcomes of hypertensive crisis in Korean children. The aim of this study was to determine the etiologies and efficacy of drugs for hypertensive crisis in children during the past 5 years at a single center in Korea.

METHODS

We analyzed data from 51 children with hypertensive crisis during the period between January 1, 2010 and April 1, 2014. The patients were divided into two groups: those diagnosed with a hypertensive emergency (hypertension with organ injury, n = 31) and those diagnosed with a hypertensive urgency (hypertension without organ injury, n = 20). Baseline etiologies and risk factors were compared between the two groups. In addition, systolic and diastolic blood pressures were evaluated at 1, 2, 4, and 5 hours after the administration of intravenous antihypertensive drugs.

RESULTS

Kidney injury and cancer were the common causes in patients with hypertensive crisis. Cardiovascular complications (cardiac hypertrophy) (p = 0.002), central nervous system complications (p = 0.004), and retinopathy (p = 0.034) were more frequently observed in children with hypertensive emergency than those with hypertensive urgency. However, the proportion of renal complications was similar in both groups. Hydralazine was most commonly used in both groups to control acute increasing blood pressure at first. However, it was often ineffective for controlling abrupt elevated blood pressure. Therefore, intravenous antihypertensive drugs were changed from hydralazine to nicardipine, labetalol, or nitroprusside to control the high blood pressure in 45.1 % of the patients. Particularly, in patients with hypertensive crisis, there was no significant difference in reduction of systolic and diastolic blood pressure and in improvement of clinical outcomes between nicardipine and labetalol administration.

CONCLUSION

Close blood pressure monitoring and careful examinations should be mandatory in children with underlying disease, especially renal diseases and cancer. Furthermore, both nicardipine and labetalol may be effective antihypertensive drug in lowering high blood pressure in children with hypertensive crisis.