What manifestation indicates poor perfusion?

A. Opiate drugs cause respiratory acidosis by depressing the central nervous system, specifically the respiratory centers in the brainstem, leading to reduced ventilation and accumulation of carbon dioxide. This increases arterial PCO2, lowering blood pH. The patient’s exposure to opiates aligns with this mechanism, as it impairs the physiological need for adequate respiration, a key component of Maslow’s hierarchy.

B. Atelectasis results in respiratory acidosis due to collapsed alveoli, which reduces effective gas exchange and causes carbon dioxide retention. This elevates PCO2, decreasing pH. The patient’s condition of atelectasis directly contributes to hypoventilation, supporting this classification.

C. Hypoventilation leads to respiratory acidosis by decreasing alveolar ventilation, causing carbon dioxide buildup. Elevated PCO2 lowers blood pH. The patient’s hypoventilation directly correlates with this mechanism, as it disrupts the respiratory system’s ability to maintain acid-base balance.

D. Renal failure causes metabolic acidosis by impairing the kidneys’ ability to excrete hydrogen ions and reabsorb bicarbonate, leading to acid accumulation and reduced serum bicarbonate. This aligns with the patient’s renal failure, as it disrupts the renal regulation of acid-base homeostasis, a critical physiological need.

E. Airway obstruction results in respiratory acidosis by preventing adequate ventilation, leading to carbon dioxide retention and increased PCO2, which lowers pH. The patient’s airway obstruction directly causes this imbalance, impairing respiratory function.

F. Diarrhea causes metabolic acidosis due to excessive loss of bicarbonate-rich intestinal fluids, reducing serum bicarbonate and lowering pH. The patient’s diarrhea aligns with this mechanism, as it leads to a direct loss of base, disrupting acid-base equilibrium.

Choice A reason: Fluid excess causes weight gain due to increased water retention in tissues and vascular spaces. This is common in conditions like heart failure or renal dysfunction, where fluid accumulates, increasing body mass, making this a correct manifestation.

Choice B reason: Edema, swelling from fluid accumulation in interstitial spaces, is a hallmark of fluid excess. It occurs when hydrostatic or oncotic pressures are imbalanced, as in heart or kidney failure, making this a correct manifestation.

Choice C reason: Fluid excess typically increases blood pressure due to expanded blood volume, as seen in heart failure. Decreased blood pressure is not a direct result of fluid overload, making this choice incorrect for fluid excess.

Choice D reason: Crackles in the lungs occur in fluid excess, as fluid leaks into alveoli (pulmonary edema) due to increased hydrostatic pressure, often in heart failure. This impairs gas exchange, making this a correct manifestation.

Choice E reason: Jugular vein distension results from fluid excess increasing venous pressure, often in right heart failure. Expanded blood volume distends neck veins, a visible sign of fluid overload, making this a correct manifestation.