A nurse is preparing to administer warfarin to a client who has chronic atrial fibrillation. Which of the following laboratory values should the nurse monitor prior to administering the medication?

A. Elevate the head of the client's bed for 1 hr after the feeding:Elevating the head of the bed helps prevent aspiration and promotes proper digestion by using gravity to keep the feeding solution in the stomach or jejunum.

B. Administer the feeding solution at a cold temperature: Feeding solutions should be administered at room temperature to prevent gastrointestinal discomfort or cramping.

C. Rotate the jejunostomy tube once per day:
Rotation of the jejunostomy tube is not a standard practice. Jejunostomy tubes are typically secured in place, and rotation is not necessary.

D. Flush the tube with 90mL of sterile water before and after the feeding:
Typically, the tube is flushed with about 30 mL of water before and after feedings to ensure patency and prevent clogging, not 90 mL.

Choice A Reason:
Absence of Chvostek's sign is a wrong indication. Chvostek's sign is a twitching of facial muscles in response to tapping the facial nerve and is typically associated with low blood calcium levels (hypocalcemia). It's not directly related to hyperglycemia or high blood sugar levels. Hyperglycemia refers to high blood sugar levels, commonly associated with diabetes mellitus.
Choice B Reason:
Presence of Kussmaul respirations is a right indication. Kussmaul respirations are deep, rapid, and labored breathing patterns often seen in individuals with diabetic ketoacidosis (DKA), a severe complication of diabetes characterized by significantly high blood sugar levels and the presence of ketones in the blood and urine. This type of breathing pattern is the body's attempt to compensate for the acidic state caused by high blood sugar and the buildup of ketones.
Choice C Reason:
Presence of diaphoresis is a wrong indication. Diaphoresis refers to excessive sweating, which can occur due to various reasons such as physical activity, heat, stress, or certain medical conditions. While hyperglycemia can cause symptoms like increased thirst and frequent urination, diaphoresis alone is not a specific indicator of high blood sugar levels.
Choice D Reason:
Absence of urinary ketones is a wrong indication. The presence of urinary ketones indicates the body is breaking down fat for energy, which commonly occurs during periods of insufficient insulin (such as in hyperglycemia or diabetic ketoacidosis). However, the absence of urinary ketones doesn't necessarily rule out hyperglycemia. It's possible for hyperglycemia to be present without ketones in the urine, especially in the early stages or when the body is still managing blood sugar levels without significant ketone production.