A nurse is assessing a client who has preeclampsia and received a dose of calcium gluconate to treat magnesium sulfate toxicity.
Which of the following findings should the nurse identify as an indication that calcium gluconate was effective?

The correct answer is Choice C

Choice A rationale: Clinical manifestations of hypovolemic shock typically begin when approximately 15% to 30% of total blood volume is lost. In pregnancy, total blood volume increases by about 30% to 50%, so signs may be masked initially. However, waiting until 20% loss to expect symptoms is misleading. Tachycardia, pallor, and hypotension may appear earlier. Therefore, this statement underestimates the sensitivity of maternal physiology to blood loss and is not scientifically accurate.

Choice B rationale: Hemorrhagic shock leads to tissue hypoperfusion and anaerobic metabolism, resulting in lactic acid accumulation and metabolic acidosis. This causes a decrease in serum pH, not an increase. Normal serum pH ranges from 7.35 to 7.45. In shock states, pH often drops below 7.35, indicating acidosis. An increase in pH would suggest alkalosis, which is not consistent with the pathophysiology of hemorrhagic shock. Thus, this statement contradicts basic acid-base science.

Choice C rationale: Urine output is a direct and sensitive indicator of renal perfusion and overall organ perfusion. The kidneys require adequate blood flow to maintain glomerular filtration. In shock, decreased cardiac output reduces renal perfusion, leading to oliguria. Normal urine output is ≥30 mL/hr. Persistent reduction below this threshold reflects compromised perfusion. Unlike blood pressure or heart rate, urine output is less influenced by compensatory mechanisms, making it a reliable marker of end-organ function.

Choice D rationale: Fluid resuscitation in hemorrhagic shock typically involves a 3:1 ratio of isotonic crystalloid (e.g., lactated Ringer’s) to blood loss volume. This accounts for the distribution of fluid into the interstitial and intracellular compartments. Administering only 1 mL of fluid per 1 mL of blood loss is insufficient to restore intravascular volume. The 3:1 replacement rule is based on fluid dynamics and vascular compartmentalization. Therefore, this statement misrepresents standard resuscitation protocols.

Choice A rationale

Monitoring blood pressure every 30 minutes following epidural placement is important but not the initial action. Epidural anesthesia can lead to a sudden drop in blood pressure, so frequent monitoring is crucial. However, the initial step should focus on preventing hypotension.

Choice B rationale

Administering lactated Ringer's 500 mL bolus via intermittent IV infusion prior to epidural placement helps in maintaining blood pressure. Epidural anesthesia can cause vasodilation, leading to hypotension. Preloading with fluids ensures adequate blood volume and reduces the risk of a significant drop in blood pressure.

Choice C rationale

Administering oxygen via nasal cannula at 2 L/min prior to epidural placement is not necessary unless the client has respiratory complications. Oxygen supplementation is used to treat or prevent hypoxia, which is not a primary concern in this scenario.

Choice D rationale

Repositioning the client every hour following epidural placement is important to ensure even distribution of the anesthetic and prevent pressure sores. However, this is not the initial action to take for preventing hypotension.