Correct Answer: C

Rationale: The correct answer is the presence of breathing and adequacy of breathing. It is crucial not only to confirm that the client is breathing but also to ensure that the breathing is adequate for proper oxygenation. Choices A, B, and D are incorrect because while pulse rate, breathing pattern, and patient position are relevant aspects to consider, the most critical observations in assessing a client's breathing are the presence and adequacy of breathing.

Correct Answer: C

Rationale: A stab wound to the chest might result in lung collapse and mediastinal shift that, if untreated, could lead to death. Treatment of an obstructed airway or a chest wound is a higher priority than hemorrhage. The principle of ABC (airway, breathing, and circulation) prioritizes care decisions. In this scenario, the stab wound to the chest poses the highest risk to the client's life as it can lead to severe complications such as lung collapse and mediastinal shift. Addressing this injury promptly is crucial to prevent further harm or potential fatality. Open leg fracture, open head injury, and traumatic amputation of a thumb, while serious, do not pose an immediate life-threatening risk compared to a stab wound to the chest.

Correct Answer: D

Rationale: The correct answer is 1.3 mEq/L. The therapeutic range for Lithium levels typically falls between 0.6 to 1.2 mEq/L. Values below or above this range can lead to suboptimal treatment outcomes or toxicity. Choices A, B, and C are within the therapeutic range of 1.0-1.2 mEq/L, making them appropriate levels for patient care.

Correct Answer: B

Rationale: The correct answer is a hyperglycemic patient. The signs described - weak pulse, quick respiration, acetone breath, and nausea - are indicative of hyperglycemia. A hypoglycemic patient would typically present with different signs such as pale skin, sweating, and confusion. Cardiac arrest would manifest with sudden loss of heart function and consciousness, not the signs described. End-stage renal failure would present with symptoms related to kidney dysfunction like edema, fatigue, and changes in urine output, which are not mentioned in the scenario.

Correct Answer: D

Rationale: A combined low PO2 and low SaO2 indicate hypoxia. The pH, PCO2, and HCO3 are normal. ABGs are not necessarily altered in TB or pleural effusion. In pneumonia, the PO2 and PCO2 might be low due to hypoxia stimulating hyperventilation, but the given ABG values specifically point to hypoxia as the primary issue.