Breathlessness

Immediate Care of Dyspnoe

OXYGEN THERAPY:

Emergency use of oxygen:

Oxygen is a treatment for hypoxaemia, not breathlessness. (Oxygen has not been shown to have any effect on the sensation of breathlessness in non-hypoxaemic patients.)

The essence of this guideline can be summarised simply as a requirement for oxygen to be prescribed according to a target saturation range and for those who administer oxygen therapy to monitor the patient and keep within the target saturation range.

Key Recommendations:

·         The recommended target saturation range for acutely ill patients not at risk of respiratory failure is 94–98%. Some normal subjects, especially people aged  over 70 years, may have oxygen saturation measurements below 94% and do not require oxygen therapy when clinically stable.

·         Most non-hypoxaemic breathless patients do not benefit from oxygen therapy, but a sudden reduction of more than 3% in a patient’s oxygen saturation within the target saturation range should prompt fuller assessment of the patient because this may be the first evidence of an acute illness.

·         For most patients with known chronic obstructive pulmonary disease (COPD) or other known risk factors for respiratory failure (eg, morbid obesity, chest wall deformities or neuromuscular disorders), a target saturation range of 88–92% is suggested pending the availability of blood gas results.

·          Because oxygenation is reduced in the supine position, fully conscious hypoxaemic patients should ideally be allowed to maintain the most upright posture possible (or the most comfortable posture for the patient) unless there are good reasons to immobilise the patient (eg. skeletal or spinal trauma).

Guidelines:

·         The initial oxygen therapy is nasal cannulae at 2–6 l/min (preferably) or simple face mask at 5–10 l/min unless stated otherwise.

·         For patients not at risk of respiratory failure who have saturation  less than 85%, treatment should be commenced with a reservoir mask at 10–15 l/min.

·         The recommended initial oxygen saturation target range is 94–98%.

·         If oximetry is not available, give oxygen as above until oximetry or blood gas results are available.

·         Change to reservoir mask if the desired saturation range cannot be maintained with nasal cannulae or simple face mask (and ensure that the patient is assessed by senior medical staff).

·         If these patients have co-existing COPD or other risk factors for  respiratory failure, aim at a saturation of 88–92% pending blood gas results but adjust to 94–98% if the PaCO2 is normal (unless there is a history of previous respiratory failure requiring NIV or IPPV and recheck blood gases after 30–60 min).

Breathing/breathlessness
Acute breathlessness can be the result of:

·         Respiratory disease

·         Cardiac Disease

·         Psychological distress

·         Dysfunctional breathing

·         Adverse lifestyle factors such as obesity or smoking

When nursing a patient with dyspnoea you must look at them and observe:

·         Rate of breathing: Measure respiratory rate by visual observation. A rate equal to or greater than 25 breaths per minute indicates acute severe asthma

·         Effort: Observe for the use of accessory muscles of respiration.

·          Breathlessness: Assess whether the patient is able to complete a sentence in one breath.

Nursing involves caring and supporting patients as patients will eventually be extremely anxious. These patient-nurse interactions are an important aspect of managing patients with dyspnoea. A thorough nursing assessment and measurement of observations allows the nurse to gain an understanding of how patients are managing their breathlessness. A nursing assessment will include asking the patient:

·         What makes them breathless,

·         What makes their breathing easier/worse,

·         Their previous medical history,

·         Current and past medications,

·         Their smoking history.

Also listen for the presence of an expiratory wheeze. This may be accompanied by an inspiratory wheeze.  
Arterial blood gases
Arterial blood gases should always be measured. Although a physician usually obtains the arterial blood gas sample, the nurse should be aware of the importance of the results (Evans, 1994).
Arterial blood gas measurements indicate acute severe asthma when the patient has a partial pressure of oxygen (PaO₂) of <8kpa (60mmHg) (normal range 12.0­13.3kpa; 90­100mmHg), and a partial pressure of carbon dioxide (PaCO₂) that may be normal (5­6kpa; 34­45mmHg) or raised. Additionally, the patient may have a low pH (<7.35) (normal range 7.34­7.45) or high hydrogen ion concentration (H⁺) (>38­42). The patient's oxygen saturation (SaO₂) may be <92% (normal range >96%). The presence of cyanosis (pallor, blueness of lips) indicates the existence of severe hypoxia and needs to be monitored closely.
Blood pressure and pulse
Record blood pressure and pulse regularly -- an increase in pulse rate over 110 beats
per minute is putting the patient at risk. Hypotension and bradycardia are life-threatening signs. Electrocardiograph monitoring is a useful adjunct in the detection of arrhythmias.

References

Brooker, R. (2004). The effective assessment of acute breathlessness in a paitent. Nursing Times. 100 (24), 61.

Cruickshank, J and Lumley, K (1999) Immediate management of acute severe asthma in adults. British Journal of Nursing. Vol 8: issue 2: pp. 103-108

The British Thoracic Society. (2008) Guideline for emergency oxygen use in adult patients. Thorax. 63 96) pp. 8-11