preload refers to

NCLEX-RN

NCLEX RN Exam Prep

1. What does preload refer to?

A. The volume of blood entering the left side of the heart
B. The volume of blood entering the right side of the heart
C. The pressure in the venous system that the heart must overcome to pump the blood
D. The pressure in the arterial system that the heart must overcome to pump the blood

Correct answer: B

Rationale: Preload refers to the volume of blood that enters the right side of the heart. This volume stretches the fibers in the heart before contraction. Preload is an essential factor in determining the force of ventricular contraction. Choices A, C, and D are incorrect. Choice A is incorrect because preload is specifically related to the volume of blood entering the right side of the heart. Choices C and D are incorrect as they refer to afterload, which is the pressure that the heart must overcome to pump blood out of the ventricles into the systemic or pulmonary circulation.

2. A healthcare professional is preparing to administer an enteral feeding through a gastrostomy tube. Before administering the feeding, the healthcare professional aspirates some stomach contents and checks the pH. The result is 3.9. What is the next action of the healthcare professional?

A. Administer the feeding as ordered
B. Pull the feeding tube out approximately 3 cm
C. Flush the feeding tube with 60 cc of water
D. Contact the physician

Correct answer: A

Rationale: When the pH of the aspirated stomach contents is 4 or less, it indicates that the gastrostomy tube is in the stomach, confirming correct placement. A pH of 3.9 falls within this range, so the healthcare professional can proceed with administering the enteral feeding. There is no need to adjust the tube placement, flush with water, or contact the physician in this situation as the tube is appropriately positioned for feeding.

3. A 70-year-old man has a blood pressure of 150/90 mm Hg in a lying position, 130/80 mm Hg in a sitting position, and 100/60 mm Hg in a standing position. How should the nurse evaluate these findings?

A. These readings are a normal response and attributable to changes in the patient's position.
B. The change in blood pressure readings is called orthostatic hypotension.
C. The blood pressure reading in the lying position is within normal limits.
D. The change in blood pressure readings is considered within normal limits for the patient's age.

Correct answer: B

Rationale: The correct answer is, 'The change in blood pressure readings is called orthostatic hypotension.' Orthostatic hypotension is defined as a drop in systolic pressure of �20 mm Hg or �10 mm Hg drop in diastolic pressure that occurs with a quick change to a standing position. This condition is common in individuals on prolonged bed rest, older adults, those with hypovolemia, or taking specific medications. The blood pressure readings provided in the question (150/90 mm Hg lying, 130/80 mm Hg sitting, and 100/60 mm Hg standing) demonstrate a significant change in blood pressure with position changes, which is indicative of orthostatic hypotension. Choices A, C, and D are incorrect because the readings do not indicate a normal response or blood pressure within normal limits for the patient's age; rather, they suggest the presence of orthostatic hypotension.

4. In the term 'Hemoglobin,' the suffix '-globin' means:

A. Protein
B. Iron
C. Metal
D. Blood

Correct answer: A

Rationale: The suffix '-globin' in the term 'Hemoglobin' specifically refers to a protein. Hemoglobin is a protein found in red blood cells that carries oxygen. Choice B, 'Iron,' is incorrect as iron is a mineral component of hemoglobin but not the meaning of the suffix. Choice C, 'Metal,' is too broad and not specific to the meaning of the suffix in this context. Choice D, 'Blood,' is incorrect as it refers to the overall term 'Hemoglobin' rather than the specific meaning of the suffix '-globin.' Therefore, the correct answer is A: 'Protein.'

5. A client is preparing to irrigate a colostomy. Which of the following situations is a contraindication for this type of irrigation?

A. The client has an incontinent ostomy
B. The client has an irregular bowel routine
C. The client has diverticulitis
D. The colostomy bag contains fecal material

Correct answer: C

Rationale: When a client with a colostomy is preparing for irrigation, it is essential to consider contraindications that could pose risks or worsen the client's condition. Diverticulitis is a contraindication for colostomy irrigation because the inflamed diverticula could be further irritated by the flushing action during irrigation, potentially leading to complications. An incontinent ostomy, irregular bowel routine, or presence of fecal material in the colostomy bag are not specific contraindications for irrigation and can be managed through appropriate techniques and interventions.