Why are patients with ischemic stroke in the medial right cerebral artery treated with 5% dextrose (glucose) in isotonic fluid and insulin?

From the Guidelines

Patients with ischemic stroke in the medial right cerebral artery are treated with 5% glucose in isotonic fluid and insulin to manage hyperglycemia while maintaining adequate cerebral perfusion. This approach is crucial because elevated blood glucose levels during acute stroke are associated with worse outcomes and larger infarct volumes, as noted in the guidelines for the early management of patients with acute ischemic stroke 1. The 5% glucose solution provides necessary calories while the isotonic component prevents cerebral edema that could result from hypotonic fluids. Insulin is administered concurrently to tightly control blood glucose levels, typically aiming for a target range of 140-180 mg/dL, as recommended for critically ill patients, including those with diabetes mellitus 1. This combination therapy addresses the stress hyperglycemia commonly seen in stroke patients while preventing hypoglycemia, which could exacerbate neuronal damage. Key considerations in the management of hyperglycemia in acute ischemic stroke include:

• Initiating insulin therapy for persistent hyperglycemia starting at a threshold of 180 mg/dL 1
• Maintaining a target glucose range of 140 to 180 mg/dL to avoid both hyperglycemia and hypoglycemia 1
• Regular monitoring of blood glucose levels, initially every 1-2 hours, and adjusting the treatment based on the patient's response 1
• Being cautious in the correction of glucose to avoid hypoglycemia, which can be detrimental 1 The right medial cerebral artery supplies critical brain regions, including motor and sensory cortices, and maintaining optimal glucose metabolism in the penumbra (the at-risk tissue surrounding the infarct core) is essential for limiting the extent of permanent damage. This treatment should be initiated promptly upon admission and continued through the acute phase of stroke management. It is also important to consider the guidelines for intravenous fluids in patients with acute ischemic stroke, which recommend maintaining euvolemia and avoiding hypotonic solutions that could exacerbate cerebral edema 1. Overall, the management of hyperglycemia in patients with ischemic stroke in the medial right cerebral artery requires careful consideration of the balance between glucose control and the risk of hypoglycemia, as well as attention to the patient's overall fluid status and cerebral perfusion.

From the Research

Treatment of Hyperglycemia in Acute Ischemic Stroke

• Hyperglycemia after acute ischemic stroke is associated with poor outcomes, and treatment protocols aim to control blood glucose levels 2, 3, 4, 5, 6.
• The use of 5% dextrose (glucose) in isotonic fluid and insulin is a common approach to manage hyperglycemia in patients with acute ischemic stroke, as it allows for the administration of insulin while maintaining glucose levels 2.
• Studies have shown that intensive glucose control, targeting blood glucose levels between 80-130 mg/dL, can be effective in reducing glucose levels, but may also increase the risk of hypoglycemia 2, 5.
• The American Diabetes Association recommends initiating therapy to achieve glucose targets of 140 to 180 mg/dL if fasting glucose is greater than 140 mg/dL or random glucose is consistently higher than 180 mg/dL 3.
• Continuous glucose monitoring has been used to assess glucose variability and demonstrate the risk of hyperglycemic and hypoglycemic events in patients with acute ischemic stroke 4.

Glucose Management in Acute Ischemic Stroke

• The goal of glucose management in acute ischemic stroke is to maintain blood glucose levels within a target range, typically between 140-180 mg/dL, to minimize the risk of poor outcomes 3, 6.
• Patients with acute ischemic stroke who present with extreme or persistent hyperglycemia, are critically ill, or are treated with thrombolytic therapy may require more aggressive glucose control using intravenous insulin protocols 3.
• The use of insulin infusion protocols, such as the one described in 2, can be effective in achieving target glucose levels, but requires close monitoring to prevent hypoglycemia.
• The association between acute and chronic hyperglycemia and outcomes in patients with acute ischemic stroke has been studied, with findings suggesting that both are associated with increased mortality and worse clinical outcomes 6.