Which symptom commonly follows the initial neurological symptoms of lidocaine toxicity?

Lidocaine toxicity can manifest with a range of neurological symptoms, typically starting with symptoms such as tinnitus, dizziness, or a metallic taste. Following these initial symptoms, it is common for patients to develop more severe complications. One of the notable outcomes is the occurrence of cardiac arrhythmias.

When lidocaine levels become elevated, they can significantly affect the cardiac conduction system. Lidocaine is a class 1B antiarrhythmic agent, and in toxic doses, it can lead to both central nervous system effects and cardiac side effects. Arrhythmias may include bradycardia, ventricular tachycardia, and other conduction disturbances due to the drug's effects on sodium channels in cardiac myocytes. This demonstrates how the impact of lidocaine extends beyond merely neurological symptoms to potential serious cardiac consequences.

While seizures, visual disturbances, and respiratory distress can also occur with lidocaine toxicity, cardiac arrhythmias are particularly concerning as they directly relate to the drug’s action on cardiac tissues and are critical to recognize in the context of managing a patient who has experienced lidocaine toxicity. This recognition is vital for immediate intervention and management of the patient.