1. Oxygen Therapy British Thoracic Society Guideline for
oxygen use in healthcare and
emergency settings
12/05/2017
Key messages for nurses
and PAMs (Professions Allied to Medicine)

2. Important Points to Consider About Oxygen Therapy
Oxygen is a life saving drug for hypoxaemic patients. (Patients whose oxygen levels are low)
Giving too much oxygen is unnecessary as oxygen cannot be stored in the body
COPD patients (and some other patients) may be harmed by too much oxygen as this can lead to increased carbon dioxide (C02) levels
Other patients (e.g. myocardial infarction) may also be harmed by too much oxygen
Only give as much as needed– no need for extra!

3. Oxygen (02) What’s the problem?
Published audits have shown:
Doctors and nurses have a poor
understanding of how oxygen should be used
Oxygen is often given without a prescription
(In the 2015 BTS audit, 42% of hospital patients using oxygen had no prescription)
If there is a prescription, patients do not always receive what is specified on the prescription
Where there is a prescription with target range, almost one third of patients are outside the range
(9.5% of SpO2 results below target range and 21.5% above target range in 2015 BTS audit)

4. Oxygen is a drug and should be prescribed except in emergencies
Oxygen should be regarded as a drug (BNF 2016)
Oxygen must be prescribed in all situations
(except for the immediate management of critical illness in accordance with BTS guidelines) (NPSA Oct 2009)
Oxygen should be prescribed to achieve a target saturation (Sp02) which should be written on the drug chart or electronic prescription

5. Aims of emergency oxygen therapy
• To correct potentially harmful hypoxaemia
• To alleviate breathlessness (only if hypoxaemic)
Oxygen has not been proven to have any consistent effect
on the sensation of breathlessness in non-hypoxaemic patients.
Benefit has been found with use of a hand-held fan and consider
use of opioids for patients with malignancy or other causes of
chronic severe breathlessness.

6. Oxygen therapy is only ONE element of
resuscitation of a critically ill patient
The oxygen carrying power of blood may be increased by
• Safeguarding the airway
• Enhancing circulating volume
• Correcting severe anaemia
• Enhancing cardiac output
• Avoiding/reversing respiratory depressants
• Giving Oxygen therapy
• Establish the reason for hypoxaemia and treat the underlying cause (e.g
Bronchospasm, LVF etc)
• Some patients may need specialist care!!

7. Oxygen therapy by first responders in critical illness
See BTS 0xygen guideline section 8.10
Patients must not go without oxygen while waiting for
a medical review
• Initial 02 therapy is reservoir mask at 15 litres/minute (RM15)
• Once stable aim for SpO % or patient-specific target range
• COPD patients who are critically ill should have the same oxygen
therapy until blood gases have been obtained and may then need controlled oxygen therapy or non-invasive or invasive ventilation

8. Prescribing to a Target Saturation range
• Oxygen will be prescribed in order to keep Sp02
within a specified range for individual patients
• Target oxygen saturation prescription is
integrated into the patient’s drug chart and
bedside monitoring
• Oxygen delivery device and/or flow should be
changed if necessary to keep the SpO2 in the
target range

9. Normal Oxygen saturation range in healthy adults
Daytime
Sp %
*Transient dips in saturation are common during sleep (~84%)

10. Patients will be initially prescribed a target saturation as shown below: -
94-98% Most patients (Those not at risk of CO2 retention)
88-92% COPD or C02 retaining patients: Chronic hypoxic lung disease
COPD
Severe Chronic Asthma
Bronchiectasis / CF
Chest wall disease
Kypho-scoliosis
Neuromuscular disease
Obesity hypoventilation
Other Some patients with oxygen sensitivity may require a different lower
target range such as 85-90%
Target saturations should be reviewed and changed if required.
This guideline recommends an upper limit of 98% for most patients
Combination of what is normal and safe

11. Target saturation prescribing
• It is recommended that all patients are routinely prescribed a target saturation on admission to hospital.
• This is so that the right target range will be used if the patient deteriorates and used in conjunction with the EWS.
• Patients will only receive oxygen if the saturation is below the target. Medical review required
when this happens.

12. Safeguarding patients at risk of type 2 respiratory failure
Lower target saturation range for these patients (usually 88-92%)
Education of patients and health care workers
Use of controlled oxygen via Venturi masks and low flow nasal O2
Use of oxygen alert cards
Issue of personal Venturi masks to high-risk patients

13. OXYGEN ALERT CARD

14. Doctors (and other prescribers) Registered Nurses / Physios
Who does what?
Doctors (and other prescribers)
Prescribe O2 target range for ALL patients
Usually 94-98% or
88-92%
Specify starting device
Review patient accordingly
Provide advice to nurses if the clinical condition of the patient changes
Adjust the target range if the patient’s condition alters (e.g. new hypercapnia)
Registered Nurses / Physios
Document starting device/flow
Start O2 and ensure target
achieved quickly
Titrate O2 to keep in range
Sign drug chart every drug round (Registered nurses)
Monitor O2 minimum 4 hourly.
Record SpO2 & delivery device
Wean off 02 if clinically stable
Codes to be written on obs chart and initialled
HCAs / Student nurses
Monitor O2 minimum 4 hourly
Record SpO2 and delivery device
Codes recorded on obs chart and initialled
Inform nurses when SpO2 outside target range

15. Oxygen prescription chart

16. Monitoring & starting oxygen therapy
Record SpO2 before starting oxygen therapy where possible.
(Do NOT take oxygen off an acutely unwell patient to obtain a reading on air)
If target saturation is 94-98%
• Choose mask and/or flow rate to achieve target saturation
• Repeat blood gases are not needed for these patients if within target range
If target saturation is 88-92%
• Start with nasal cannulae at 1-2 l/minute or 28% Venturi mask then titrate to achieve the target saturation
• Blood gases are needed after mins
If ‘Other’ Sp02 prescribed - start as directed by doctor
Monitor SpO2 for first 5 mins and then monitor patient SpO2 minimum 4 hourly.
Record delivery device and flow on observations chart.

17. Core content of an oxygen observation chart
If the patient is medically stable and in the target range on two consecutive rounds, report to a registered nurse to consider weaning off oxygen.
Standard abbreviations for oxygen delivery devices

18. Maintaining the Target saturation
• Nurses must use the oxygen escalator (see next slide)
• Masks and flow rate should be changed up or down to ensure target saturation range is met as quickly as possible
• Nurses do not need to use each step of the escalator and can change devices and/or flow rate to ensure target SpO2 is achieved
e.g. 2 Litre nasal cannula may change to 35% Venturi mask
Always monitor SpO2 for 5 mins after any change in oxygen therapy to ensure target saturation is achieved

19. Titrating Oxygen up and down using the mask escalator
BTS NURSES TRAINING SLIDES MAY 2010(V13)
Titrating Oxygen up and down
using the mask escalator
This table below shows APPROXIMATE conversion values.
OR Nasal Cannulae 1L
OR Nasal Cannulae 2L
OR Nasal Cannulae 4L
OR Simple face mask
OR Simple face mask 7-10L/min
Reservoir mask at 15L oxygen flow
If reservoir mask is required, seek senior medical input immediately
Venturi 24% (BLUE) 2-3 L/M
Venturi 28% (WHITE) 4-6 L/M
Venturi 35% (YELLOW) 8-12 L/M
Venturi 40% (RED) L/M
Venturi 60% (GREEN) 15 L/M

20. Titrating oxygen up or down in Target saturation range 94-98%
Increase oxygen if SpO2 is lower than target range
Decrease oxygen if SpO2 is higher than target range
• Monitor SpO2 for 5 mins at every change
• Document SpO2 on chart after 5 mins
• If oxygen therapy is increased, medical assessment is needed and blood gases may be required
• If oxygen therapy is decreased for a stable
patient, blood gases are NOT needed
No need to inform doctor if clinically stable
Ensure change is documented in patient record

21. Titrating 02 up or down in Target saturation range 88-92% or other
Increase oxygen if SpO2 is lower than target range
Decrease oxygen if SpO2 is higher than target range
- Monitor SpO2 for 5 mins at every change
- Document SpO2 on chart after 5 mins
- If oxygen therapy is increased, take blood gases after minutes (show doctor results)
- If oxygen therapy is decreased for a stable patient, blood gases are NOT needed
No need to inform doctor if clinically stable
Ensure change is documented in patients record

22. Stopping oxygen therapy for stable patients
Stop 02 if patient stable and Sp02 is within range on 2 consecutive observations
• Patient will usually be weaned to low dose oxygen by this time
• Stop supplemental oxygen & monitor Sp02 for 5mins & document this in the chart
• If Sp02 remains stable, continue on air for 1 hour monitoring Sp02
• Document Sp02 on chart at end of hour
• If stable at one hour, the patient is weaned off oxygen and continues regular obs
If saturation falls on stopping oxygen, then re-start the previous dose
If cases of acute deterioration or if Sp02 fall outside of the target
range despite re-starting oxygen therapy, the patient should have an
immediate medical review

23. When to use the Target saturation not indicated box (To be used for patients who do not benefit from pulse oximetry monitoring)
• Some patients may be on oxygen for conditions where it is inappropriate to continue with observations.
• A tick in the box means no oxygen observations/documentation in medical records
• Qualified nurses must still sign the drug chart each round
This may apply to patients for
• Palliative care
• Symptom control in last days of life

24. Devices to use

25. High Concentration Reservoir Mask (RM)
• Non re-breathing Reservoir Mask
• Critical illness / Trauma patients
• Post-cardiac or respiratory arrest
• Delivers O2 concentrations
between 60 & 80% or above
• Effective for short term treatment

26. Nasal Cannulae (N) Recommended for most patients.
1-6 L/min gives approx 24-50% FIO2
FIO2 depends on oxygen flow rate and
patient’s minute volume and inspiratory
flow and pattern of breathing.
Comfortable and easily tolerated
No re-breathing
Patient can eat and drink
Preferred by patients (vs simple mask)
Low cost product

27. Venturi or fixed performance masks (V)
Aims to deliver constant oxygen concentration within
and between breaths.
The minimum oxygen flow is displayed.
With TACHYPNOEA (RR >30/min) the oxygen flow should be increased by 50% - see next slide
Increasing flow does not increase oxygen
concentration, it is a fixed dose device
Good device for patients with raised C02 (patients with
a target of 88-92%)

28. Simple face mask (SM) (Medium concentration, variable performance)
• Used for patients with type I respiratory failure
• Delivers variable O2 concentration between 35% & 60%
• Low cost product
• Flow 5-10 L/min
Flow must be at least 5 L/min to avoid CO2 build up and resistance to breathing

29. Humidified Oxygen (H) • Tracheostomy • Bronchiectasis
• Cystic Fibrosis patients
• Physiotherapists may advise humidification
• Patients on High flow whisper CPAP
• Humidification may be provided by cold or warm humidifiers
• ( H24, H28, H35 etc.)
The illustration shows a cold humidifier delivering 28% oxygen at 5 l/min flow.
N.B. There is little evidence for humidification in routine oxygen therapy.

30. Tracheostomy mask (TM)
• “Neck breathing patients” • Adjust oxygen flow to maintain target saturation • Prolonged oxygen use requires humidification • Patients may also need suction to remove airway mucus

31. High flow nasal oxygen (HFN)
High flow nasal oxygen using specialised equipment may be used as an alternative to reservoir mask treatment in patients with acute respiratory failure without hypercapnia
It is mostly used in Intensive Care Units, High Dependency Units and other specialised areas

32. Oxygen flow meter The centre of the ball indicates the correct flow rate.
The ball must be centred on the
line.
This diagram illustrates the correct
setting of the flow meter to deliver a flow of 2 litres per minute.

33. Beware of air outlets They may be mistaken for oxygen outlets
Use a cover for air
outlets or else
remove the flow
meter for air when
not in use
Oxygen outlet
(Usually white)
Air outlet
(usually black)

34. Patients receiving Oxygen leaving your Ward environment.
Porters and SHCA (trained and competent) are able to transfer patients receiving oxygen
Up to 8Lpm via venturi mask or 4Lpm via nasal specs or simple mask ……………………..any exclusions to this?
Does the patient require a nurse escort due to their condition regardless of flow rate
Signed oxygen transfer sheet for porters.
Never reduce a patients oxygen to avoid a Registered Nurse escort
Always consider the consequences of postponing investigations if a nurse escort is required and the ward is stretched.

35. Oxygen prescribing Summary
• Oxygen is a life saving drug • Oxygen must be prescribed (in emergencies, give immediately, record later) • Doctors will prescribe a target saturation range for all patients • Prescription will be written in oxygen section of drug chart or EPR • Nurses will choose device and flow rate to achieve target saturation • Nurses can titrate oxygen up & down & record on obs chart (Medical review is required after up-titration of oxygen) • Nurses can wean stable patients off oxygen • Oxygen must be monitored minimum four hourly • Nurses must sign drug chart for oxygen at every drug round