From the Research
Hyperkalemia causes confusion primarily by disrupting normal electrical activity in the brain, leading to cognitive symptoms like confusion, disorientation, and in severe cases, altered consciousness. When potassium levels in the blood become too high (typically above 5.5 mEq/L), the excess potassium alters the electrical gradient across cell membranes throughout the body, including neurons in the brain. This disruption affects neurotransmission and normal brain function, leading to cognitive symptoms. The confusion occurs because neurons rely on precise potassium-sodium balance to generate action potentials and communicate effectively.
Key Points to Consider
- Hyperkalemia often causes cardiac arrhythmias that may reduce blood flow to the brain, further contributing to confusion through cerebral hypoperfusion 1.
- Patients with kidney disease, those taking certain medications (like ACE inhibitors, ARBs, potassium-sparing diuretics), or individuals with adrenal insufficiency are at higher risk 1.
- Treatment involves addressing the underlying cause, restricting dietary potassium, and in severe cases, administering calcium gluconate, insulin with glucose, beta-agonists, or dialysis to rapidly lower potassium levels and resolve the neurological symptoms 2, 3.
Management of Hyperkalemia
The management of hyperkalemia is crucial to prevent morbidity and mortality. Calcium gluconate 10% dosed 10 mL intravenously should be provided for membrane stabilization, unless the patient is in cardiac arrest, in which case 10 mL calcium chloride is warranted 2. Additionally, insulin with glucose, beta-agonists, or dialysis may be necessary to rapidly lower potassium levels and resolve the neurological symptoms. It is also important to monitor for hypoglycemia, especially when using insulin therapy, and to adjust the dosing of insulin and glucose accordingly 3.
Recent Advances
Recent studies have highlighted the importance of understanding the pathophysiology of hyperkalemia and its consequences, including the risk of cardiac arrhythmias and cerebral hypoperfusion 1. The use of newer potassium binders, such as patiromer and sodium zirconium cyclosilicate, may also play a role in the management of hyperkalemia, particularly in patients with chronic kidney disease or heart failure 2.