Choice A rationale:
Hyperventilation is a condition characterized by rapid and deep breathing, leading to excessive removal of carbon dioxide (CO2) from the body. This decrease in CO2 levels actually causes respiratory alkalosis, not respiratory acidosis.
CO2 is a weak acid, and its removal from the blood raises the blood pH, making it more alkaline. Key mechanisms involved in hyperventilation-induced respiratory alkalosis:
Increased alveolar ventilation: Hyperventilation increases the rate at which CO2 is expelled from the lungs, reducing its concentration in the blood.
Shift in the equilibrium of the carbonic acid-bicarbonate buffer system: The reduction in CO2 levels drives the equilibrium towards the formation of bicarbonate ions, further reducing the concentration of hydrogen ions and increasing pH.
Renal compensation: The kidneys respond to respiratory alkalosis by excreting more bicarbonate ions, which helps to normalize the blood pH.
Choice B rationale:
Asthma is a chronic respiratory disease characterized by inflammation and narrowing of the airways. This can lead to impaired ventilation and retention of CO2, which can contribute to respiratory acidosis.
Mechanisms by which asthma can cause respiratory acidosis:
Bronchoconstriction: Narrowed airways impede airflow, making it difficult to expel CO2 from the lungs.
Air trapping: Inflammation and mucus production can lead to air becoming trapped in the lungs, further increasing CO2 levels.
Hypoventilation: Severe asthma attacks can cause respiratory muscle fatigue, leading to a decrease in breathing rate and inadequate CO2 removal.
Choice C rationale:
Chronic obstructive pulmonary disease (COPD) is a group of lung diseases characterized by chronic obstruction of airflow. This obstruction can lead to impaired ventilation and retention of CO2, which can contribute to respiratory acidosis.
Mechanisms by which COPD can cause respiratory acidosis:
Emphysema: Destruction of lung tissue reduces the surface area available for gas exchange, making it difficult to expel CO2. Chronic bronchitis: Inflammation and mucus production in the airways can obstruct airflow and trap CO2 in the lungs.
Hypoventilation: COPD can lead to respiratory muscle fatigue and a decrease in breathing rate, further impairing CO2 removal.
Choice D rationale:
Pulmonary embolism (PE) is a blockage of an artery in the lungs, usually by a blood clot. This can lead to impaired gas exchange and a decrease in oxygen levels in the blood. In severe cases, PE can also cause respiratory acidosis due to inadequate CO2 removal.
Mechanisms by which PE can cause respiratory acidosis:
Ventilation-perfusion mismatch: PE obstructs blood flow to a portion of the lungs, reducing the amount of CO2 that can be removed from those areas.
Hypoxemia: Low oxygen levels in the blood can stimulate the respiratory drive, leading to hyperventilation and CO2 retention.
Right heart failure: PE can strain the right side of the heart, leading to decreased pulmonary blood flow and impaired CO2 removal.

Rationale for Choice A:

Arranging for a bedside commode can be helpful for patients who have difficulty ambulating to the bathroom. However, it is not the most effective intervention for preventing falls in an ambulatory and independent patient. In fact, it could potentially increase the risk of falls if the patient attempts to use the commode without assistance or if they become disoriented in the dark.

Research has shown that bedside commodes are associated with an increased risk of falls in hospitalized patients. This is because patients may try to get out of bed to use the commode without assistance, or they may become disoriented in the dark and fall.

Additionally, bedside commodes can be a tripping hazard, especially for patients with impaired mobility.

Rationale for Choice B:

Ensuring the bathroom light is kept on during the night can help to reduce the risk of falls by making it easier for the patient to see. However, it is not the most effective intervention for preventing falls.

Patients may still fall even if the bathroom light is on, especially if they are weak, unsteady, or have impaired vision. Additionally, keeping the bathroom light on all night can disrupt the patient's sleep, which can also increase the risk of falls.

Rationale for Choice C:

Using side rails to keep the patient in bed is not an effective intervention for preventing falls. In fact, it can actually increase the risk of falls by making it more difficult for the patient to get out of bed safely.

Patients may try to climb over the side rails, which can lead to falls.

Additionally, side rails can restrict the patient's movement and make them feel trapped, which can lead to agitation and an increased risk of falls.

Rationale for Choice D:

Implementing a toileting schedule is the most effective intervention for preventing falls in an ambulatory and independent patient. This is because it helps to reduce the patient's need to get out of bed at night to use the bathroom.

When a patient has a scheduled time to toilet, they are less likely to try to get out of bed on their own and risk a fall. Additionally, a toileting schedule can help to prevent incontinence, which can also lead to falls.