Final answer:
After vagal maneuvers fail to resolve a patient's condition, the next step is to consider pharmacological intervention with drugs like adenosine or proceed to synchronized cardioversion if necessary.
Step-by-step explanation:
If you have performed vagal maneuvers on a patient and there is no change observed on the monitor, the next step is to consider pharmacological intervention. This may include administering antiarrhythmic drugs such as adenosine, which can quickly terminate certain types of supraventricular tachycardias that do not respond to vagal maneuvers. It's important to continuously monitor the patient's vital signs and cardiac rhythm when administering these medications. If the patient is hemodynamically unstable or the arrhythmia persists, synchronized cardioversion may be indicated. In all instances, maintaining communication with the rest of the healthcare team and preparing for potential advancement to more invasive interventions is crucial.