Home Oxygen Safety During Cancer Care

Home oxygen is a prescribed drug delivered as a gas. Like any drug it has a dose, which here means a flow rate in liters per minute, a device, and a number of hours per day. It is ordered because the oxygen level in your blood is too low, not simply because you feel short of breath.

In cancer care, low oxygen can come from a tumor blocking an airway, fluid around the lung or heart, a clot in the lung vessels, or weakened breathing muscles. It can also follow treatment, such as lung scarring after radiotherapy, heart muscle weakened by chemotherapy, or lung inflammation from immunotherapy. Older problems such as chronic lung disease, heart failure and anemia often sit underneath.

Two things follow from that. Oxygen treats the low level, not the cause. And breathlessness and low oxygen are not the same thing. Some people feel terrible with a normal reading, and morphine, a fan on the face, and positioning often help that more than turning the flow up.

Call emergency services (911 in the US, 999 or 112 in the UK) if:

• Your oxygen reading on a finger probe is 88 percent or lower.
• Lips, gums or fingernails look blue or grey.
• You are gasping at rest, cannot speak a full sentence, or your breathing has gone irregular.
• You are getting hard to wake, drowsy, or confused.
• Chest pain or a racing heart comes with the breathlessness.

Call your team the same day if:

• Your finger probe reads 92 percent or lower at rest.
• You need noticeably more oxygen, or more hours on it, than last week.
• You wake with headaches most mornings.
• You have a temperature of 38.0 °C / 100.4 °F or higher. The CDC uses 100.4 °F and the NCI uses 100.5 °F. Use the lower number.
• New ankle swelling, a new cough, or colored or bloody phlegm appears.

A normal reading sits between 95 and 100 percent. Some people with long-standing lung disease are given a lower personal target, so ask for yours in writing. Finger probes are also imperfect. Readings can run 2 to 4 percent above or below the true value, and dark nail polish, false nails, cold hands, poor circulation, smoking and darker skin pigmentation can all skew them. Trust how you look and feel over the number.

Never raise your flow rate on your own. In some people, too much oxygen slows breathing rather than helping it. Ask your team what to do when you feel worse, and write the answer down before you need it.

This is the part most people get wrong. Oxygen does not burn, and a home cylinder is not a bomb. What oxygen does is soak into everything around it: bedding, clothes, hair, beard, upholstery, tissues. That is called an oxygen-enriched atmosphere, and enrichment "increases the energy, heat release and severity of any fire". Materials that would not normally catch light can burn fiercely and give off choking fumes within seconds.

So a small spark that would have died out becomes a room fire. And it starts on your face, where the tubing is.

The numbers are not abstract. A European Respiratory Journal review reports that in UK data, home fires involving oxygen happen at twice the rate of house fires in the general population. US fire departments responded to an estimated 182 home fires a year in which home oxygen equipment was directly involved, and 46 people died in those fires each year, with smoking "by far the leading factor". Separately, home medical oxygen was involved in an average of 1,190 thermal burns seen annually in US emergency rooms.

Rules that actually matter:

• Nobody smokes. Not the patient, not a visitor, not in the next room, not "just by the window". This includes vapes and e-cigarettes, which contain a battery and a heating coil.
• Put a NO SMOKING sign on the door of any room where oxygen is used.
• Stay at least 6 feet, about 2 metres, away from space heaters, wood stoves, fireplaces, gas hobs, candles, electric blankets and electric appliances such as hairdryers.
• Be careful in the kitchen. Keep oxygen away from the stovetop and oven, and watch for splattering grease, which can catch fire. Cooking with a microwave is usually OK.
• Keep working smoke detectors and a working fire extinguisher in the house, and check them routinely. If you move around the house with your oxygen, you may need more than one extinguisher.
• Do not put Vaseline or any petroleum-based cream on your face, nose or upper body. Use aloe vera or a water-based gel instead.
• Keep away anything that burns easily: cleaning products containing oil, grease or alcohol, aerosol sprays, and hand gels near a flame.
• Never store cylinders in a car boot, a box, or a small closet. Under the bed is fine if air moves freely there.
• Tell your local fire department, electric company and telephone company that oxygen is in use in your home. A fire service or community fire safety officer may visit to go over fire safety, smoke alarms and escape routes.

A concentrator pulls oxygen out of room air. It never runs out and never needs refilling, but it needs mains power and it needs a backup cylinder. Compressed gas cylinders hold oxygen under pressure. Liquid oxygen stores far more in a smaller container and is easier to carry.

Most people breathe it through a nasal cannula: soft tubing that loops over the ears with two short prongs in the nostrils. Replace the cannula every 2 to 4 weeks, and sooner if it is stiff or crusted. A mask is used for higher flows.

Tell your supplier about every alarm you hear, and ask what each one means before it goes off at night.

Long tubing is freedom and a trip hazard at once. Run it along walls, not across doorways, and keep it out from under chair legs and wheels. Tape down anything that crosses a walking route.

Dry nostrils, nosebleeds and sore ears are common. Ask about a humidifier bottle, water-based gel, and foam pads for behind the ears. Check the skin over the ears and cheeks daily.

Plan for a power cut before one happens. A concentrator needs mains power, so you must have a backup tank of oxygen gas in case of a power failure. Ask your supplier how many backup cylinders you should hold and how quickly they deliver, and make sure your electric company knows oxygen is in use. Keep a torch and the supplier's out-of-hours number beside the concentrator.

For travel, tell the airline at least two weeks ahead. Ask specifically whether your portable device is approved for the flight, and how many charged batteries you must carry.

• MedlinePlus — Oxygen safety
• MedlinePlus — Using oxygen at home
• MedlinePlus — Pulse oximetry
• European Respiratory Journal (PMC) — Home oxygen therapy and domestic fires
• NCI PDQ — Cardiopulmonary Syndromes (patient version)
• CDC — Watch Out for Fever (Preventing Infections in Cancer Patients)