ATI RN
Questions for Muscular System Questions
Question 1 of 5
When preparing a patient for electromyography (EMG), the nurse will instruct the patient to:
Correct Answer: B
Rationale: EMG assesses muscle and nerve function by recording electrical activity, requiring clear signals. Caffeine, a stimulant, can increase muscle tension or jitteriness, potentially skewing results, so avoiding it for 3 hours prior is standard. Smoking cessation for 12 hours isn't typically required, as its effect on EMG is less direct. Muscle relaxants would dampen activity, defeating the test's purpose of measuring natural responses. While EMG can take time, 2 hours isn't standard for all cases, and preparation focuses more on accuracy than duration. Refraining from caffeine ensures the test reflects true neuromuscular status, making it the key instruction for reliable outcomes.
Question 2 of 5
While the nurse is giving morning care to a patient who sustained a fractured pelvis and bilateral fractures of the femur in a motorcycle accident yesterday, the patient complains of shortness of breath and is audibly wheezing. An assessment of the oxygen saturation reveals 76%. The initial intervention by the nurse should be to:
Correct Answer: C
Rationale: Sudden shortness of breath, wheezing, and 76% oxygen saturation post-fracture suggest a fat embolism, a life-threatening complication from long bone trauma. Administering oxygen at 4-5 L/min via nasal cannula is the initial step to boost oxygenation, stabilizing the patient while further help is sought. Alerting the code team is premature without first aiding breathing. Informing the charge nurse follows oxygen delivery, as does raising to high Fowler's to ease breathing but oxygen comes first. This rapid response addresses hypoxia directly, critical in trauma where respiratory decline can escalate fast, buying time for diagnosis and treatment.
Question 3 of 5
The pelvic floor; the space between the anus and the scrotum in the male and between the anus and the vulva in the female.
Correct Answer: C
Rationale: The perineum is the region of the pelvic floor between the anus and scrotum in males or vulva in females, encompassing both the anal and urogenital triangles. It serves as the external base of the pelvic cavity and contains muscles, nerves, and other structures. Compartment refers to muscle groups, not this region. The urogenital triangle is only part of the perineum, not the whole area. Fixators are stabilizing muscles, unrelated to this anatomical space. The perineum's definition matches the question perfectly, making it the correct answer, as it broadly describes the pelvic floor area between these landmarks, critical for understanding pelvic anatomy and clinical conditions like perineal tears.
Question 4 of 5
This type of muscle works by stabilizing the origin of the agonist so that it can act more efficiently.
Correct Answer: D
Rationale: Fixators stabilize the origin of the agonist (prime mover), ensuring its force is directed efficiently toward the intended movement. For example, during arm abduction, scapular fixators (e.g., trapezius) hold the scapula steady so the deltoid can lift the arm. Synergists assist the agonist by refining motion, not stabilizing origins. The agonist is the main mover, not a stabilizer. Antagonists oppose the agonist. Fixators' role in anchoring the origin enhances movement precision, making it the correct answer, as it supports the agonist's action by preventing unwanted shifts at the stationary attachment, a key aspect of coordinated muscle function.
Question 5 of 5
Tim ate something that is not agreeing with his digestive tract. He needs to go to the bathroom to defecate, but there is a line. What muscle helps keep the anal canal and anus closed?
Correct Answer: D
Rationale: The external anal sphincter, a voluntary skeletal muscle, keeps the anal canal and anus closed to prevent defecation until appropriate, allowing Tim to wait. Bulbospongiosus aids in urination and erection, not anal control. Ischiocavernosus supports erection, not defecation. Obturator internus rotates the thigh, unrelated here. The external anal sphincter is the correct answer, as it provides conscious control over defecation, distinct from the involuntary internal sphincter, and is key in maintaining continence under digestive distress.