A woman has had her left breast removed for cancer. She also had an axillary node dissection on the left during surgery. How would this affect placement of an intravenous line?

Correct Answer: C

Rationale: In this scenario, the correct answer is C) The left arm should not be used. The reason for this is that when a woman has had her left breast removed for cancer and also underwent an axillary node dissection on the left side during surgery, it increases the risk of lymphedema and infection in that arm. Lymphedema is a condition that results from a blockage in the lymphatic system, leading to swelling and an increased risk of infection. Using the left arm for intravenous line placement in this situation can further exacerbate the risk of lymphedema and infection. Therefore, to minimize the potential complications and ensure patient safety, healthcare providers should avoid using the left arm for procedures like intravenous line insertion. Regarding the other options: - A) Either arm may be used: This is incorrect because using the left arm, in this case, poses a higher risk due to the lymph node dissection and potential complications. - B) Neither arm should be used: This is overly restrictive and not necessary. The right arm can still be used safely for intravenous line placement. - D) The right arm should not be used: This is incorrect as the right arm is not affected by the breast removal or lymph node dissection on the left side. Educationally, understanding the implications of surgical procedures on patient care is crucial for healthcare professionals. It highlights the importance of considering a patient's medical history and past surgeries when making decisions about procedures to prevent complications and ensure the best possible outcomes for the patient.

Correct Answer: D

Rationale: In this question regarding drugs associated with hypokalemia, the correct answer is D) amiloride. Amiloride is considered a potassium-sparing diuretic, which means it works by promoting potassium retention in the body, thus not leading to hypokalemia. Loop diuretics (option A) such as furosemide and corticosteroids (option B) like prednisone are known to cause hypokalemia by increasing the excretion of potassium in the urine. Gentamicin (option C), an antibiotic, can also lead to hypokalemia as a side effect by affecting renal function and potassium balance. Educationally, it is important for students to understand the mechanisms of action of different drug classes and their potential side effects. Understanding which drugs can lead to electrolyte imbalances like hypokalemia is crucial for healthcare professionals in order to anticipate, prevent, and manage potential complications in patients. This knowledge is particularly relevant in fields such as nursing, pharmacy, and medicine where medication management plays a significant role in patient care.

Correct Answer: B

Rationale: In the context of hyperkalemia, the correct answer is B) Peak T wave. This is because hyperkalemia, which is an elevated level of potassium in the blood, can affect the electrical activity of the heart. The earliest ECG change seen in hyperkalemia is the tall, peaked T wave. This occurs due to the increased potassium levels disrupting the normal repolarization process of the ventricles, leading to the characteristic T wave changes. Option A) Sine wave is incorrect because it is a severe ECG finding in hyperkalemia, usually seen after the peaked T waves progress. Option C) Flattened P wave is associated with conditions like hypokalemia or atrial enlargement, not hyperkalemia. Option D) QRS widening is a later ECG change in hyperkalemia, reflecting more severe cardiac conduction disturbances. Understanding these ECG changes in hyperkalemia is crucial for healthcare professionals, especially those working in emergency or critical care settings. Recognizing these early signs can prompt timely interventions to prevent life-threatening cardiac arrhythmias associated with severe hyperkalemia. It is essential for healthcare providers to stay vigilant and monitor electrolyte imbalances, like hyperkalemia, as they can have profound effects on the cardiovascular system and patient outcomes.

Correct Answer: D

Rationale: In this question, the correct answer is D: "calcium chloride has less elemental calcium than calcium gluconate." This is because calcium chloride actually has more elemental calcium, around 27%, compared to calcium gluconate which has about 9%. Option A is incorrect because the normal correct range for total calcium is 2.1-2.5 mmol/L, not 2.1-2.5 as stated. Option B is incorrect because the correct range for ionized calcium is 1.14-1.3 mmol/L, not 1.14-1.3. Option C is incorrect as well because to correct for low albumin, you add 0.8 to the total calcium for every 4 the albumin is below 40, not 36. Educationally, understanding the correct levels and properties of calcium is crucial for healthcare professionals, particularly in the context of patient care. Calcium plays a vital role in various physiological processes, and abnormal levels can have serious implications for a patient's health. By knowing the correct ranges and properties of calcium preparations, healthcare providers can make informed decisions regarding patient treatment and management. This knowledge is essential for ensuring patient safety and optimal outcomes in clinical practice.

Correct Answer: B

Rationale: The correct answer to the question is option B: calculated serum osmolality = 2(Na+) + glucose + urea. This formula calculates the osmolality of the serum by taking into account the major osmotically active particles in the blood, which are sodium, glucose, and urea. Osmolality is a crucial parameter in assessing the body's water and electrolyte balance. Option A is incorrect because the anion gap equation is correctly represented as (Na+ + K+) - (Cl- + HCO3-) where the anion gap helps in diagnosing metabolic acidosis. Option C is incorrect as the correct formula for calculating partial pressure of oxygen (paO2) is paO2 = (pO2 - paCO2) / 0.8, which is used in assessing gas exchange in the lungs. Option D is incorrect because the expected CO2 in metabolic acidosis should be calculated using the formula 1.5 x HCO3- + 8, which helps in determining the compensatory response to metabolic acidosis. Understanding these equations and their correct interpretations is vital for healthcare professionals, especially in fields like critical care, nephrology, and emergency medicine. Mastery of these formulas enhances the ability to diagnose and manage patients with various acid-base and fluid balance disorders, ultimately leading to improved patient outcomes.