What is the management of a hypertensive emergency, particularly with potential hyperparathyroidism (Hyperparathyroidism) impact?

From the Guidelines

Management of a hypertensive emergency with suspected hyperparathyroidism requires immediate blood pressure reduction while addressing the underlying calcium abnormality. Initial treatment should focus on lowering blood pressure gradually using intravenous medications like nicardipine (5 mg/hour, titrated by 2.5 mg/hour every 5-15 minutes), labetalol (20 mg bolus followed by 20-80 mg every 10 minutes or 1-2 mg/minute infusion), or clevidipine (1-2 mg/hour, doubled every 90 seconds as needed) as recommended by the 2020 international society of hypertension global hypertension practice guidelines 1. Target a 20-25% reduction in blood pressure within the first hour, then gradual normalization over 24-48 hours to prevent organ hypoperfusion. Simultaneously, assess serum calcium, phosphorus, PTH levels, and renal function. If hyperparathyroidism is confirmed, hydration with normal saline (typically 1-2 L) helps promote calcium excretion. Furosemide (20-40 mg IV) can enhance calcium excretion after adequate hydration. Bisphosphonates like zoledronic acid (4 mg IV over 15 minutes) or pamidronate (60-90 mg IV over 2-4 hours) may be used for severe hypercalcemia. Cinacalcet (30 mg twice daily) can be considered for ongoing management. Hyperparathyroidism complicates hypertensive emergencies by promoting vasoconstriction, reducing vascular compliance, and impairing renal function through hypercalcemia, making blood pressure more difficult to control and increasing end-organ damage risk. The esc council on hypertension position document on the management of hypertensive emergencies also supports the use of intravenous antihypertensive drugs for the treatment of hypertensive emergencies in patients with selected comorbidities 1. Additionally, the 2017 acc/aha/aapa/abc/acpm/ags/apha/ash/aspc/nma/pcna guideline for the prevention, detection, evaluation, and management of high blood pressure in adults provides guidance on the management of hypertensive emergencies, including the use of intravenous antihypertensive drugs and the importance of addressing underlying conditions such as hyperparathyroidism 1.

Some key points to consider in the management of hypertensive emergencies include:

• The type of target organ damage is the principal determinant of the choice of treatment, target BP, and timeframe by which BP should be lowered 1.
• The use of oral therapy is discouraged for hypertensive emergencies, and intravenous medications are preferred 1.
• The goal of treatment is to minimize target organ damage safely by rapid recognition of the problem and early initiation of appropriate antihypertensive treatment 1.
• Hyperparathyroidism can complicate hypertensive emergencies by promoting vasoconstriction, reducing vascular compliance, and impairing renal function through hypercalcemia, making blood pressure more difficult to control and increasing end-organ damage risk.
• The management of hypertensive emergencies requires a comprehensive approach that addresses the underlying causes of the condition, including hyperparathyroidism, and involves the use of intravenous antihypertensive drugs, hydration, and other therapies as needed.

From the FDA Drug Label

The time course of blood pressure decrease is dependent on the initial rate of infusion and the frequency of dosage adjustment. Nicardipine hydrochloride injection is administered by slow continuous infusion at a concentration of 0. 1 mg/mL. With constant infusion, blood pressure begins to fall within minutes. It reaches about 50% of its ultimate decrease in about 45 minutes For a gradual reduction in blood pressure, initiate therapy at a rate of 5 mg/hr. If desired blood pressure reduction is not achieved at this dose, increase the infusion rate by 2. 5 mg/hr every 15 minutes up to a maximum of 15 mg/hr, until desired blood pressure reduction is achieved.

The management of a hypertensive emergency with potential hyperparathyroidism impact is not directly addressed in the provided drug labels. However, for the management of hypertensive emergencies, nicardipine hydrochloride injection can be administered by slow continuous infusion at a concentration of 0.1 mg/mL, with the initial rate of infusion and frequency of dosage adjustment determining the time course of blood pressure decrease.

• The infusion rate can be initiated at 5 mg/hr and increased by 2.5 mg/hr every 15 minutes up to a maximum of 15 mg/hr until the desired blood pressure reduction is achieved.
• It is essential to monitor patients closely, especially those with impaired cardiac, hepatic, or renal function 2. However, the specific impact of hyperparathyroidism on this management is not addressed in the provided labels.

From the Research

Management of Hypertensive Emergency

The management of hypertensive emergency involves the rapid controlled reduction of blood pressure to prevent or minimize end-organ damage 3, 4, 5, 6, 7.

• The selection of a specific antihypertensive agent should be based on the agent's pharmacology and patient-specific factors, such as comorbidity and the presence of end-organ damage 3.
• Intravenous antihypertensive agents available for the treatment of hypertensive emergencies include nicardipine, nitroprusside, fenoldopam, nitroglycerin, enalaprilat, hydralazine, labetalol, esmolol, and phentolamine 3, 4, 5.
• Newer agents such as clevidipine have also been shown to be effective in reducing mortality compared to nitroprusside 4.

Potential Impact of Hyperparathyroidism

There is no direct evidence in the provided studies on the impact of hyperparathyroidism on the management of hypertensive emergency.

• However, it is essential to consider the patient's clinical status, including cardiac, neurologic, and renal functions, when selecting a treatment option 5.
• The presence of hyperparathyroidism may be a comorbidity that needs to be considered when choosing an antihypertensive agent 3.

Treatment Approach

The treatment approach for hypertensive emergency should be based on a symptoms- and evidence-based algorithm, such as the BARKH-based algorithm, which allows for quick identification of hypertensive emergencies and associated acute organ damage 6.

• Therapeutic intervention should be a short-acting, easily titratable, intravenous antihypertensive medication based on the type of end-organ damage, pharmacokinetics, and comorbidities 7.