A nurse is providing care to a client who is immunocompromised.

Which of the following should the nurse identify as a possible source of infection?

The plantar Babinski reflex is assessed by stroking the sole of the foot from the heel towards the toes. A normal response is the flexion or curling of the toes. An abnormal response, known as a positive Babinski sign, is the extension and fanning out of the toes, which indicates an upper motor neuron lesion.

"Place your foot in my hand and I will tap the back of your heel": This instruction is more relevant to testing the Achilles tendon reflex, where the nurse taps the back of the heel to elicit a plantarflexion response.

"Sit on the edge of the bed while I tap your knee": This instruction is more relevant to testing the patellar reflex, also known as the knee-jerk reflex. The nurse taps the patellar tendon just below the kneecap to elicit a reflexive contraction of the quadriceps muscle.

"Relax your arm across your chest and I will test your elbow extension": This instruction is more relevant to testing the triceps reflex, where the nurse taps the triceps tendon to elicit a reflexive extension of the elbow.

This step is part of the process when mixing NPH and regular insulin in a single syringe. After injecting air into the NPH insulin vial, you should inject an equal amount of air (in this case, 15 units) into the regular insulin vial to maintain pressure balance. This allows for easy withdrawal of the prescribed doses of each insulin type in the same syringe without causing a vacuum in the vials.

After injecting air into the NPH insulin vial (step 1), the nurse should proceed to inject air into the regular insulin vial (step 2) before withdrawing the insulin doses in the subsequent steps.

Verifying the dosage with another nurse is not necessary in this step, as it is done prior to drawing up the insulin. However, it is good practice to have another nurse double-check the dosage before administration.

Injecting air into the regular insulin vial is not required at this stage. It is only necessary when withdrawing the regular insulin dose.

Placing the cap over the needle should be done after withdrawing the desired dose of insulin and before administering it to the client for safety and to prevent needlestick injuries.

The correct sequence when mixing NPH and regular insulin in a single syringe is as follows:

1. Inject air into the NPH insulin vial (in this case, 10 units of air).
2. Inject air into the regular insulin vial (in this case, 15 units of air).
3. Withdraw the prescribed dose of NPH insulin (10 units) from the NPH vial.
4. Withdraw the prescribed dose of regular insulin (15 units) from the regular insulin vial.

So, after injecting air into the NPH insulin vial (step 1), the nurse should proceed to inject air into the regular insulin vial (step 2) before withdrawing the insulin doses in the subsequent steps.