A 26-year-old patient who was injured in a motorcycle accident is brought into the Intensive Care Unit (ICU) and placed on a mechanical ventilator.
The ABG values just obtained are: pH 7.24, CO2 of 68, HCO3 of 25. What should be the nurse's first priority?

Choice A rationale

Administering bicarbonate would address the metabolic component if it were present, but the primary issue here is respiratory acidosis, indicated by the elevated CO2 and low pH. Bicarbonate could worsen the respiratory acidosis by shifting the equilibrium and further depressing respiratory drive in some cases. Normal HCO3 is 22-26 mEq/L.

Choice B rationale

The ABGs indicate respiratory acidosis (pH 7.24, CO2 68 mmHg, HCO3 25 mEq/L). Increasing the respiratory rate and depth allows for greater CO2 exhalation, thereby decreasing the partial pressure of carbon dioxide (PCO2) and raising the pH back towards the physiological normal range of 7.35-7.45. Normal CO2 is 35-45 mmHg.

Choice C rationale

Morphine is an opioid that depresses the central nervous system, including the respiratory drive. Administering morphine would further exacerbate the existing respiratory acidosis by decreasing the patient's respiratory rate and depth, leading to even higher CO2 retention and a further drop in pH.

Choice D rationale

Decreasing the respiratory rate and depth would worsen the patient's hypercapnia, meaning an even higher CO2 level. This would further lower the pH, exacerbating the respiratory acidosis and potentially leading to more severe physiological compromise due to inadequate gas exchange and ventilation.

Choice A rationale

The absence of lung sounds on the right side would indicate a problem in the right lung, such as a right-sided pneumothorax or severe atelectasis of the right lung. Given the scenario specifies a left-sided pneumothorax, the primary assessment findings would be localized to the affected (left) side, not the contralateral side.

Choice B rationale

A left-sided pneumothorax, characterized by air accumulating in the pleural space on the left side, will lead to collapse of the left lung. This collapse will result in an absence of breath sounds and diminished or absent chest rise on the affected (left) side due to the lung's inability to inflate and participate in ventilation.

Choice C rationale

Hypertension (elevated blood pressure) and bradypnea (slow respiratory rate) are not typical primary findings in an acute pneumothorax. While a pneumothorax can cause respiratory distress, it often leads to tachypnea (increased respiratory rate) as the body attempts to compensate for reduced lung function and potentially hypotension due to impaired venous return.

Choice D rationale

Lack of chest rise bilaterally would indicate a more generalized respiratory issue, such as severe bilateral atelectasis, bilateral mainstem bronchus obstruction, or a severe neurological impairment affecting respiratory drive. In a unilateral pneumothorax, the contralateral lung would typically still demonstrate some degree of chest rise, although it might be diminished. .