A nurse in an emergency department is caring for an infant who has a 2-day history of vomiting and an elevated temperature. Which of the following should the nurse recognize as the most reliable indicator of fluid loss?

For a child with hemophilia experiencing a joint injury, the best home treatment and therapy would be elevation and the application of ice to the affected joint. This approach helps reduce swelling and minimize bleeding in the joint.
Option A (factor VIII concentrates) is a treatment for hemophilia but is typically administered intravenously to replace the deficient clotting factor in the blood. It is not a home treatment for joint injuries.
Option C (nonsteroidal anti-inflammatory drugs - NSAIDs) may be used to manage pain and inflammation, but they do not address the underlying bleeding disorder in hemophilia or directly treat joint injuries.
Option D (DDAVP - synthetic vasopressin) is used in some types of hemophilia to temporarily raise factor VIII levels, but it is not typically used for joint injuries or as a home treatment.

A patent ductus arteriosus (PDA) is a congenital heart defect associated with increased pulmonary blood flow. In normal fetal circulation, the ductus arteriosus allows blood to bypass the lungs since the baby receives oxygen from the mother's placenta. After birth, the ductus arteriosus should close, redirecting blood flow to the lungs for oxygenation. However, in some infants with PDA, the ductus arteriosus remains open, causing an abnormal connection between the aorta and the pulmonary artery. As a result, oxygenated blood from the aorta flows back into the pulmonary artery, increasing the workload on the lungs.

The other options are as follows:
A. Coarctation of the aorta - Coarctation of the aorta is a narrowing of the aorta, which obstructs blood flow and leads to increased blood pressure in the upper body and reduced blood flow to the lower body.
C. Tetralogy of Fallot - Tetralogy of Fallot is a combination of four heart defects that results in decreased pulmonary blood flow due to a ventricular septal defect (VSD), overriding aorta, pulmonary stenosis, and right ventricular hypertrophy.
D. Tricuspid atresia - Tricuspid atresia is a congenital heart defect where the tricuspid valve does not develop correctly, resulting in an absent or abnormal tricuspid valve. This defect prevents blood flow from the right atrium to the right ventricle and, therefore, reduces pulmonary blood flow.