From the Guidelines
Midazolam (Versed) typically causes a mild to moderate decrease in blood pressure, with the hypotensive effect being more pronounced when administered intravenously, especially with rapid administration or higher doses. This benzodiazepine medication works by enhancing the effect of the inhibitory neurotransmitter GABA in the brain, which produces sedation, anxiolysis, and muscle relaxation. The blood pressure-lowering effect occurs through vasodilation and decreased peripheral vascular resistance, as well as a reduction in sympathetic nervous system activity 1.
Some key points to consider when administering midazolam include:
- Elderly patients, those with pre-existing cardiovascular disease, hypovolemia, or patients taking other medications that lower blood pressure are at higher risk for more significant drops in blood pressure.
- Healthcare providers should monitor vital signs closely, administer the medication slowly when given intravenously (typically over 2-5 minutes), ensure adequate hydration status, and have resuscitation equipment readily available.
- The typical adult IV dose ranges from 1-2.5 mg initially, titrated to effect, while oral doses for premedication are usually 0.25-0.5 mg/kg.
- Midazolam clearance is reduced in the elderly, obese, and those with hepatic or renal impairment, which may lead to increased risk of hypotension 1.
- The use of midazolam with an opioid may result in a synergistic interaction, and a reduction in the dose of midazolam may be indicated 1.
It is essential to note that the evidence from various studies, including those published in 2005 1 and 2013 1, supports the use of midazolam as a safe and effective sedative agent when used appropriately. However, the potential for hypotension and other adverse effects should always be considered, and patients should be closely monitored during administration.
From the FDA Drug Label
In cardiac hemodynamic studies in adults, intravenous induction of general anesthesia with midazolam was associated with a slight to moderate decrease in mean arterial pressure, cardiac output, stroke volume and systemic vascular resistance. In pediatric patients, a comparison of intravenous midazolam (500 mcg/kg) with propofol (2. 5 mg/kg) revealed a mean 15% decrease in systolic blood pressure in patients who had received intravenous midazolam vs a mean 25% decrease in systolic blood pressure following propofol. Fluctuations in vital signs were the most frequently seen findings following parenteral administration of midazolam in adults and included... variations in blood pressure and pulse rate. Pediatric Patients The following adverse events related to the use of intravenous midazolam in pediatric patients were reported in the medical literature: ... hypotension 2.7%
Versed (midazolam) can cause a decrease in blood pressure. The decrease in blood pressure can be slight to moderate, with a mean decrease of 15% in systolic blood pressure in pediatric patients.
- Key effects on blood pressure:
From the Research
Effect of Versed (Midazolam) on Blood Pressure
- The effect of midazolam on blood pressure has been studied in various clinical settings, with some studies suggesting a decrease in blood pressure, while others found no significant change 3, 4, 5, 6, 7.
- A study published in the Journal of Clinical Anesthesia found that midazolam did not affect blood pressure or heart rate in healthy volunteers 3.
- In contrast, a study published in Anesthesiology found that midazolam decreased mean aortic and left ventricular end-diastolic pressure in patients with coronary artery disease 4.
- Another study published in Anesthesia and Analgesia found that midazolam caused a small but statistically significant decrease in systemic and pulmonary arterial blood pressure in patients with ischemic heart disease 5.
- A randomized, double-blind, placebo-controlled study published in The British Journal of Oral & Maxillofacial Surgery found that a low dose of midazolam significantly decreased blood pressure in dental patients with transient hypertension 6.
- However, a study published in the British Journal of Anaesthesia found that bolus doses of midazolam decreased mean arterial pressure and cerebral perfusion pressure in patients with severe head injury, which could be a concern in certain clinical settings 7.
Key Findings
- Midazolam may cause a decrease in blood pressure in certain patient populations, such as those with coronary artery disease or transient hypertension 4, 6.
- However, the effect of midazolam on blood pressure may vary depending on the clinical setting and patient population 3, 5, 7.
- Further studies are needed to fully understand the effects of midazolam on blood pressure and to determine the optimal dosage and administration regimen for different patient populations.