A nurse is caring for an elderly client who had a colectomy for removal of cancer 2 days ago. The client is becoming increasingly restless. He has been given intravenous morphine every 2 hours for severe pain. Respirations are 28/min and shallow. Which arterial blood gas (ABG) results best indicate that the client is in acute respiratory failure (ARF) and needs immediate intervention?

Question

Quizplus · Accepted Answer

Normal adult ABG values at sea level are as follows: 11ecbb05_ca5a_78a3_b433_e7edca736667_MD0009_00 ARF is defined as inadequate gas exchange that is intrapulmonary (pneumonia, pulmonary embolism) or extrapulmonary (head injury, opioid overdose) in origin. Respiratory failure associated with an alteration in O₂ transfer or absorption is type I hypoxemic failure (eg, acute respiratory distress syndrome, pulmonary edema, shock). Respiratory failure associated with carbon dioxide (CO₂) retention is type II hypercapnic, or ventilatory failure (eg, chronic obstructive pulmonary disease, myasthenia gravis, flail chest). ARF is a potential complication of major surgical procedures, especially those involving the thorax and abdomen, as in this client. ABG values that indicate the presence of ARF are PaO₂ ≤60 mm Hg (8.0 kPa) or PaCO₂ ≥50 mm Hg (6.67 kPa). ARF occurs quickly over time (minutes to hours), and so there is no physiologic compensation and pH is ≤7.30. Immediate intervention with high O₂ concentrations is indicated, and noninvasive or invasive, positive-pressure mechanical ventilation may be necessary. (Option B) PaO₂ 64 mm Hg (8.5 kPa) indicates hypoxemia, and PaCO₂ 45 mm Hg (6.0 kPa) is within the normal range, but results do not meet the criteria for ARF. (Option C) PaO₂ 70 mm Hg (9.3 kPa) indicates hypoxemia, and PaCO₂ 30 mm Hg (4.0 kPa) indicates increased ventilation and an alkalotic state, but results do not meet the criteria for ARF. (Option D) PaO₂ 86 mm Hg (11.5 kPa) is within normal range, and PaCO₂ 25 mm Hg (3.33 kPa) indicates increased ventilation and an alkalotic state, but results do not meet the criteria for ARF. Educational objective: Type I hypoxemic failure is associated with an alteration in O₂ transfer (eg, acute respiratory distress syndrome, pulmonary edema, shock). Type II hypercapnic, or ventilatory, failure is associated with CO₂ retention (eg, chronic obstructive pulmonary disease, myasthenia gravis, flail chest). ABG values that indicate the presence of ARF are PaO₂ ≤60 mm Hg (8.0 kPa), PaCO₂ ≥50 mm Hg (6.67 kPa), and pH ≤7.30.

A Nurse Is Caring for an Elderly Client Who Had