Correct Answer: B

Rationale: Head lag should be completely resolved by 4 months of age. Continuing head lag at 6 months of age indicates the need for further developmental or neurological evaluation. Laying the infant on his stomach promotes muscle development of the neck and shoulder muscles, but because of the age of this child, a referral should be the first action. The findings are abnormal for a 6-month-old infant. Significant head lag can be seen in infants with Down syndrome and hypoxia, as well as neurological and other metabolic disorders. While some of these disorders might include developmental delays, stating this to the parents without a proper evaluation can cause unnecessary distress. The priority is to identify the cause of the head lag through a medical evaluation before discussing potential outcomes with the parents.

Correct Answer: B

Rationale: The Romberg test is a balance assessment that evaluates cerebellar function. During the test, the client stands with feet together and eyes closed, aiming to maintain balance for about 20 seconds. This test helps identify issues related to balance and proprioception, not hearing acuity or sound discrimination. Choices C and D are incorrect as the Romberg test focuses on balance, not distant hearing or sound discrimination.

Correct Answer: B

Rationale: The Tinel sign is elicited by percussing at the location of the median nerve at the wrist. In carpal tunnel syndrome, this test can produce burning and tingling along the nerve's distribution. Choices A, C, and D are incorrect. Testing for the strength of each muscle joint and checking for repetitive movements in the joints involve different assessments unrelated to the Tinel sign. Asking the client to flex the wrist 90 degrees while holding the hands back to back is associated with the Phalen test, which is another evaluation for carpal tunnel syndrome.

Correct Answer: C

Rationale: During the fourth stage of labor, the woman's vital signs should be assessed every 15 minutes during the first hour. An increasing pulse rate is an early sign of excessive blood loss, as the heart beats faster to compensate for reduced blood volume. The blood pressure decreases as blood volume diminishes, but this is a later sign of hypovolemia. The most common reason for excessive postpartum bleeding is a uterus that is not firmly contracting and compressing open vessels at the placental site. Therefore, the nurse should check the client's uterine fundus for firmness, height, and positioning. Checking the uterine fundus is the priority action as it helps determine if the client is bleeding excessively. Notifying the registered nurse immediately is not necessary unless the cause of bleeding is unclear and needs further intervention. Continuing to check vital signs without addressing the potential issue will delay necessary intervention. Documenting findings is important, but not the immediate priority when faced with a potential emergency situation like postpartum hemorrhage.

Correct Answer: A

Rationale: A chemical reaction between drugs before their administration or absorption is termed a drug incompatibility. This phenomenon commonly occurs when drug solutions are mixed before intravenous administration but can also happen with orally administered drugs. Choices B, C, and D are incorrect because side effects, adverse events, and allergic responses typically occur after the drugs have been administered and absorbed, not before.