A Common Device, A Critical Role
At nearly every bedside is a simple knob that puts out the amount of oxygen that goes to the patient. This amount can be adjusted quite frequently and sometimes even on a regular basis. However, the small settings of this knob are what determine how well a patient breathes, reacts, and is able to stabilize.
From Estimation to Control
In the past, oxygen delivery was not very accurate or reliable. The earlier delivery systems did not have any way for the clinician to accurately measure the oxygen flows. Clinicians had to rely on approximate values.
As use of oxygen became more widespread, it became apparent that oxygen delivery needed to become more reliable. More than just having access to oxygen, it needed to be available at a constant flow rate.
The introduction of flowmeters (or metering) allowed for the setting, measuring and replication of oxygen.
This gave way to having oxygen as a medically approved therapy.
What the Device Does
A flowmeter that measures how much oxygen will be provided to a patient. It has two connections, one to either a central supply or cylinder of oxygen. The clinician will set a value for flow in liters/min for their patient. The delivery system is usually a nasal cannula or face mask. The value set is the initial value for treatment.
More Than Just a Number
Oxygen serves a function beyond simple support; in fact, it is an effective form of treatment and requires careful adjustment based on need. Insufficient amounts of oxygen may fail to return the body back to an acceptable level of oxygen saturation; conversely, excess amounts of oxygen have the potential to create detrimental effects in patients who don’t need supplemental oxygen. Excess amounts of supplemental oxygen can alter patients’ ability to breathe properly (ex. abnormal breathing patterns) in some patients, especially those with chronic respiratory illnesses. The adjustment may be minor; however, the impact can be considerable.
Where It Becomes Critical
Patients can have different reactions to a particular environment. Oxygen use varies according to patient lung function, ventilation, and blood circulation. Likewise, the method for delivering oxygen (nasal cannula vs. mask) does not produce the same concentration of oxygen at the same flow rate. The amount of oxygen delivered will not necessarily result in the same amount of oxygen in the patient’s body.
Where Errors Begin Quietly
There's a lot of potential for error on a typical oxygen delivery system.
The flow might not be set correctly; tubing could be kinked; the device may not have a good fit on the patient; and they're likely to remove the device, etc.
The flowmeter will indicate there is flow (i.e., oxygen), but you may not be delivering effective volumes of gas to the patient.
The Illusion of Adequacy
Having a visible environment is comforting. There seem to be an effective use of oxygen.
There are many other factors affecting oxygenation besides flow rate. Delivery, absorption, and patient condition all contribute to how well oxygen will reach the patient.
Even when there has been a proper setup of the equipment used for therapy, there may still be inadequate therapy received by the patient.
Why It Matters
Oxygen therapy is one of the most common interventions in clinical care. It is used in emergencies and routine management.
Inaccurate delivery can delay recovery or worsen outcomes. Adjustments made without reassessment may lead to unintended effects.
Understanding the device is essential to using it effectively.
Closing Thought
Oxygen therapy is used in both emergencies and routine care. When delivered inappropriately, it can delay or worsen recovery, especially if changes are made without reassessment.
Effective outcomes depend not just on giving oxygen, but on understanding how it is delivered.
