HESI General Chairside Assisting Practice Exam

During which phase of a grand mal seizure does the patient experience muscle rigidity lasting 10-20 seconds?

1. Aura phase

2. Clonic phase

3. Postictal phase

4. Tonic phase

The correct answer is: Tonic phase

The phase during which a patient experiences muscle rigidity lasting 10-20 seconds in a grand mal seizure is known as the tonic phase. In this phase, the body's muscles contract and become stiff, leading to a rigid posture. This rigidity is often accompanied by a cessation of breathing and is a critical aspect of the seizure's onset. The tonic phase typically precedes the clonic phase, during which the muscles undergo rhythmic contractions and relaxations. Understanding this sequence is vital for recognizing the signs of a grand mal seizure and ensuring appropriate care and response. The other phases—such as the aura phase, which occurs shortly before the seizure and may involve sensory disturbances, and the postictal phase, which follows the seizure and includes confusion, fatigue, and other symptoms of recovery—do not involve the immediate muscle rigidity characteristic of the tonic phase.