Using capnography to confirm airway placement and monitor ventilation. An end-tidal CO2 detector measures the CO2 level in exhaled air and provides a waveform that shows CO2 is being delivered from the lungs. After securing the airway, a consistent end-tidal CO2 waveform with normal values confirms tracheal placement and effective ventilation. If CO2 is not detected or the waveform is absent, it raises concern for esophageal intubation or tube dislodgement, prompting immediate reassessment and repositioning. Capnography also helps track ventilation efficiency over time by showing trends in CO2 elimination; rising CO2 can indicate hypoventilation or rebreathing, while very low CO2 may reflect hyperventilation or poor perfusion. In contrast, a pulse oximeter only shows oxygen saturation and does not verify placement or provide immediate ventilation data, a thermometer is unrelated, and a stethoscope alone cannot reliably confirm airway placement or quantify ventilation.

Being able to participate in decisions means engaging with information, understanding what’s being offered, and weighing options. When a patient asks questions about identified treatments, it shows they are actively seeking clarification, evaluating what is presented, and considering potential consequences. That active information-processing and inquiry demonstrates decision-making capacity in that moment. Medicating for severe pain can cloud thinking and judgment, making it hard to understand information or reason about choices. A diagnosis like septic shock can bring delirium or cognitive impairment, which undermines capacity. Not understanding the medical condition similarly signals limited understanding necessary to make informed choices. Remember, capacity is task- and time-specific, so a person can have it for some decisions and not others.

Informed consent is a process where the clinician explains what will be done, what to expect, potential risks and benefits, and available alternatives, and then confirms the patient understands and agrees voluntarily. For a dressing change, the appropriate action is to provide a clear explanation of what will be done, how it will feel, any risks or discomfort, how long it will take, and any aftercare steps, and to answer questions. This conversational approach demonstrates understanding and voluntary agreement more than signing a form. Signing a consent form for a dressing change isn’t typically required, and forms to receive medications or to be turned in bed aren’t relevant to this procedure. The patient should also be allowed to ask questions and to decline if they choose.

Estimating energy expenditure relies on formulas that convert body size into metabolic needs. Height and weight are fundamental inputs because they reflect the body's mass and surface area, which drive metabolic rate. By using height and weight, you can estimate basal energy needs (BMR) and, when combined with an activity factor, total energy expenditure. The other data—food allergies, use of nutritional supplements, or ability to swallow—don’t inform how many calories the body requires; they relate to dietary restrictions, intake feasibility, or nutrition management rather than energy needs.

SpO2 reflects the percentage of hemoglobin binding sites that are occupied by oxygen, measured noninvasively with pulse oximetry. It does not measure the amount of dissolved oxygen in plasma (that’s PaO2), and it is not the same as PaO2, even though they relate through the oxygen–hemoglobin dissociation curve. SpO2 can be influenced by hemoglobin status—low hemoglobin, or abnormal forms like carboxyhemoglobin or methemoglobin can affect readings—so it isn’t independent of Hb status. Therefore, the statement that SpO2 represents the percentage of hemoglobin bound with oxygen is the correct interpretation.