A nurse is working in the emergency department when a patient arrives with suspected carbon monoxide poisoning. What is the priority nursing action?

The priority action for suspected carbon monoxide poisoning is immediate administration of 100% oxygen via non-rebreather mask to displace carbon monoxide from hemoglobin and restore oxygen-carrying capacity.

Carbon monoxide (CO) poisoning is a life-threatening emergency requiring immediate intervention. Carbon monoxide has about 200-250 times greater affinity for hemoglobin than oxygen, forming carboxyhemoglobin (COHb), which cannot effectively carry oxygen, leading to tissue hypoxia and cellular dysfunction.

The priority nursing action is administering 100% oxygen via a non-rebreather mask. High-concentration oxygen therapy is the most effective treatment for carbon monoxide poisoning. High levels of oxygen displace carbon monoxide from hemoglobin through competitive binding, reducing the half-life of carboxyhemoglobin from 4-6 hours in room air to about 60-90 minutes with 100% oxygen therapy.

The patient's headache, dizziness, and nausea symptoms, along with a history of being found unconscious near a running vehicle in an enclosed space, are classic early signs of carbon monoxide poisoning. These symptoms result from cerebral hypoxia as hemoglobin cannot deliver sufficient oxygen to tissues.

Arterial blood gas analysis, intravenous access, and neurological assessment are also important nursing components, but they are secondary to the immediate need for oxygen therapy. Following the ABC (airway, breathing, circulation) principles of emergency nursing, ensuring adequate oxygenation takes priority. Delaying oxygen administration can worsen hypoxia, leading to cardiac arrest or permanent neurological damage.

Emergency room nurses should recognize that symptoms of carbon monoxide poisoning can be subtle, and standard pulse oximetry cannot distinguish between oxyhemoglobin and carboxyhemoglobin, potentially showing normal readings. This makes clinical assessment and immediate oxygen therapy even more critical in suspected cases.

Clinical Judgment The core issue in this situation is understanding the pathophysiology of Carbon Monoxide Poisoning. Carbon monoxide (CO) has an affinity for hemoglobin that is 200-250 times greater than that of oxygen, forming Carboxyhemoglobin (COHb), which severely impairs the transport and release of oxygen to tissues. The patient's symptoms (headache, dizziness, nausea) and exposure history (a garage with a running car) strongly suggest this. Notify HCP! The top priority in this situation is to immediately halt tissue hypoxia and dissociate CO from hemoglobin. The single most effective initial intervention for this is the administration of 100% oxygen. All other actions must follow this life-saving measure.

Memory Tip
CO poisoning = Think "CO Brake." CO puts a 'brake' on oxygen transport, and 100% oxygen is the key that 'releases' that brake. The principle is "Oxygen First, Tests Later."

KR vs US
The initial response principle for CO poisoning (administering 100% oxygen) is the same in both Korea and the US. The difference may lie mainly in subsequent treatment approaches. In the US, there is a tendency to consider Hyperbaric Oxygen Therapy (HBOT) more actively for severe patients, and the criteria for its use (altered consciousness, pregnancy, high COHb levels, etc.) are often clearly defined in protocols.