Rapid continuous rewarming of frostbite primarily lessens cellular damage. Rapid rewarming is the single most effective therapy for frostbite. Heat conduction and radiation from deeper tissue circulation prevent freezing and ice crystallization until the skin temperature drops below 0°C.

Option B: Blisters contain high amounts of thromboxane and prostaglandins. They contract and dry within 2-3 weeks, forming a dark eschar that sloughs off in 4 weeks.
Option C: Before movement can be improved, the cell injury should be resolved first.
Option D: It does not prevent the formation of blisters. It does promote movement, but this is not the primary reason for rapid rewarming. It might increase pain for a short period of time as the feeling comes back into the extremity.

Hemodialysis works by using a dialyzing membrane to filter waste that has accumulated in the blood. Dialysis largely replicates the functions of the kidneys in patients with chronic kidney failure. Hemodialysis takes over the key tasks of the kidneys, removing waste materials, toxins, excess salt and fluids from the body.

Option A: In hemodialysis, an artificial kidney (hemodialyzer) is used to remove waste and extra chemicals and fluid from the blood. To get the blood into the artificial kidney, the doctor needs to make an access (entrance) into the blood vessels. This is done by minor surgery to the arm or leg.
Option B: The transfer of metabolic toxins through the membrane into the dialysis fluid is based on natural processes. This process is known as diffusion. When blood and dialysis fluid with different concentrations of molecules are separated by a semipermeable membrane, the molecules move through the membrane to the lower concentration. However, large proteins and blood cells are too big to pass through the small membrane-pores, so they remain in the blood.
Option C: A dialyzer is an artificial filter containing fine fibers. The fibers are hollow with microscopic pores in the wall, also known as semi-permeable dialysis membrane. To remove toxins during hemodialysis, a special dialysis-fluid flows through the filter, and bathes the fibers from the outside, while the blood flows through the hollow fiber. Due to the semi-permeable dialysis membrane, toxins, urea and other small particles can pass through the membrane.

The client who is immunosuppressed and is exposed to measles should be treated with medications to boost his immunity to the virus. If the patient knows that he has been exposed to measles and his CD4 count is less than 200, he should talk to his doctor about whether post-exposure prophylaxis (PEP) with immunoglobulin may be an option. PEP may provide some protection or lessen the severity of infection if it occurs. If the CD4 count is 200 or greater, PEP can also include getting the MMR vaccine. Ideally, PEP should be administered within 72 hours of exposure to measles.

Option A: Antibiotics may not be an effective treatment. One important characteristic of measles infection is that it produces more serious illness and increased mortality among immunocompromised individuals, primarily those with defects in T-cell immunity. Because >90% of the human immunodeficiency virus (HIV)–infected children live in regions where measles is still endemic, achieving high rates of measles vaccine coverage is especially important among these populations to suppress excess measles-associated morbidity and mortality.
Option C: Antivirals would not be as effective as immunoglobulins for the client with AIDS. Early identification and antiretroviral treatment of HIV-infected infants and children are critical to maximizing measles vaccine immunogenicity and providing protection against other HIV-related complications.
Option D: The patient should remain in isolation, but the administration of immunoglobulin is a priority. The impact of HIV-related immunocompromise and subsequent effects of antiretroviral therapy (ART) on immune reconstitution and, ultimately, on vaccine immunogenicity is unclear.

The client with MRSA should be placed in isolation. Gloves, a gown, and a mask should be used when caring for the client and hand washing is very important.

Option A: The door should remain closed, but a negative-pressure room is not necessary. Whenever possible, patients with MRSA will have a single room or will share a room only with someone else who also has MRSA.
Option B: MRSA is spread by contact with blood or body fluid or by touching the skin of the client. Patients are asked to stay in their hospital rooms as much as possible. They should not go to common areas, such as the gift shop or cafeteria. They may go to other areas of the hospital for treatments and tests.
Option C: It is cultured from the nasal passages of the client, so the client should be instructed to cover his nose and mouth when he sneezes or coughs. It is not necessary for the client to wear the mask at all times; the nurse should wear the mask.

Pain-related to phantom limb syndrome is due to a peripheral nervous system interruption. A recent study estimated that there were about 1.6 million people with limb loss in the USA in 2005 and this number was projected to increase by more than double to 3.6 million by the year 2050. Vascular problems, trauma, cancer, and congenital limb deficiency are among the common causes of limb loss.

Option A: Phantom limb pain can last several months or indefinitely. The phantom pain and sensation may have its onset immediately or years after the amputation. There are reports of two peak periods of onset, the first within a month and the second a year after amputation. The prevalence is reported to decrease over time after amputation.
Option C: The explanation of phantom limb pain is not psychologically related. PLP was once thought to be primarily a psychiatric illness. With the accumulation of evidence from research over the past decades, the paradigm has shifted more towards changes at several levels of the neural axis, especially the cortex. Peripheral mechanisms and central neural mechanisms are among the hypotheses that have gained consensus as proposed mechanisms over the recent years.
Option D: Pain and itching are not symptoms of an infection due to surgery. During amputation, peripheral nerves are severed. This results in massive tissue and neuronal injury-causing disruption of the normal pattern of afferent nerve input to the spinal cord. This is followed by a process called deafferentation and the proximal portion of the severed nerve sprouts to form neuromas. There is an increased accumulation of molecules enhancing the expression of sodium channels in these neuromas that results in hype-excitability and spontaneous discharges. This abnormal peripheral activity is thought to be a potential source of stump pain, including phantom pain.