X3. Refer appropriately to prevent further deterioration (‘P’)

The risk of death from exacerbations of COPD increases with acute carbon dioxide retention (respiratory acidosis), the presence of significant comorbid conditions (eg, ischaemic heart disease) and complications (eg, pneumonia and empyema). Depending on the nature and severity of the exacerbation, the patient may require urgent specialist review, hospital assessment or admission to a high-dependency or intensive care facility for ventilatory support and appropriate monitoring (see Box 13 and Box 14).

X3.1 Controlled oxygen delivery

Correction of hypoxaemia to achieve a PaO₂ of at least 55 mmHg (7.3 kPa) and an oxygen saturation of 88%–92% is the immediate priority.⁷ Where there is evidence of acute respiratory acidosis (or a rise in PaO₂), together with signs of increasing respiratory fatigue and/or obtunded conscious state, assisted ventilation should be considered. Early non-invasive positive pressure ventilation (NIPPV) may reduce the need for endotracheal intubation (see below for more detail).

Administering oxygen at an inspired oxygen concentration (fraction of inspired oxygen; FiO₂) of 24%–28% by means of a venturi mask is usually sufficient to improve oxygenation in most patients. Nasal cannulas, although more comfortable, deliver a variable concentration of oxygen, but a flow of 0.5–2.0 L per minute is usually sufficient. Gas flow provided through Hudson-type masks is inadequate when patients are tachypnoeic, so these should not be used. Careful monitoring with oximetry and, where hypercapnia is a potential concern, arterial blood gas measurement is required. There is no benefit in trying to obtain SpO₂ levels over 92%.

High flow oxygen should be avoided, as it is rarely necessary and may lead to hypoventilation and worsening respiratory acidosis. Patients should be weaned off supplementary oxygen as soon as possible, with none for 24–48 hours before discharge, unless home oxygen is prescribed.

There is currently insufficient evidence to treat acute exacerbations of COPD with Heliox mixture.

X3.2 Non-invasive positive pressure ventilation

Ventilatory support with intermittent positive pressure ventilation (IPPV) should be considered in patients with rising PaCO₂ levels who are unable to ventilate adequately (ie, acute or acute-on-chronic respiratory acidosis).^267-271This can be achieved non-invasively (by means of a face mask, NIPPV) or invasively through an endotracheal tube.^272,273

NIPPV is an effective and safe means of treatment of ventilatory failure. Its use allows preservation of cough, physiological air warming and humidification, and normal swallowing, feeding and speech. Early intervention with NIPPV is suggested when the respiratory rate is less than 30 per minute and blood pH is less than 7.35. An improvement in respiratory rate and pH usually occurs within one hour of starting NIPPV.^267-271 Failure to respond or further deterioration would indicate a need to consider intensive care unit admission (Box 14).

Applying non-invasive ventilation in addition to conventional therapy reduces mortality (Relative Risk 0.5), and the need for intubation (RR 0.4) and its potential complications. NIPPV results in more rapid improvements in respiratory rate, dyspnoea score and blood gas abnormalities than conventional therapy alone. Some studies have also shown an improvement in survival and a reduced length of stay in hospital (Weighted Mean Difference 3.24 days).^{125,267-281, 282} [evidence level I]

X3.3 Invasive ventilation (intubation)

NIPPV is contraindicated in patients who are unable to protect their airways, are not spontaneously breathing or who have severe facial injury or burns.²⁷³  Relative contraindications (situations where NIPPV may be less effective) include life-threatening refractory hypoxaemia (PaO₂< 60 mmHg, or 8 kPa on 100% inspired oxygen), bronchiectasis with copious secretions, severe pneumonia, and haemodynamic instability. These patients may require intubation. Patients who need mechanical ventilation have an inpatient mortality of 17%–30%.²⁷⁴ 

Weaning from invasive ventilation can be facilitated by the use of non-invasive positive pressure ventilation with outcomes which resulted in decreased mortality (RR 0.41) and reduced hospital length of stay (WMD 7.33 days) ²⁸³

The patient's wishes regarding intubation and resuscitation should ideally be documented before an admission for management of respiratory failure. Patients who require ventilatory support during exacerbations of COPD may have impaired control of breathing or apnoeas during sleep, even when well. Therefore, performing a diagnostic sleep study when the patient's condition is stable should be considered. Narcotic analgesics and sedatives should be avoided, as these may worsen ventilatory failure and hasten the need for positive pressure ventilation.

X3.4 Clearance of secretions

Patients who regularly expectorate or those with tenacious sputum may benefit from forced expiratory techniques. If patients produce more than 25 mL sputum per day, or if mucus plugging with lobar atelectasis is present, physiotherapy incorporating the use of postural drainage and associated techniques such as percussion and vibration may help.^105,177

X3.5 Monitor and review

The aim is to relieve hypoxaemia and obtain improvement in clinical signs and symptoms.

• Clinical examination: Reduction in wheeze, accessory muscle use, respiratory rate, distress.

• Gas exchange: Arterial blood gas levels and/or pulse oximetry levels should be monitored until the patient's condition is stable (SpO₂ 88%–92%).

• Respiratory function testing: FEV₁ should be recorded in all patients after recovery from an acute exacerbation.

• Discharge planning: Discharge planning should be commenced within 24–48 hours of admission.

X3.6 Pulmonary rehabilitation

A pulmonary rehabilitation program that includes supervised exercise training can be initiated immediately following an acute exacerbation. Such a program involves functional exercise capacity, health-related quality of life, and may reduce unplanned hospital admissions and mortality²⁸⁴ [evidence level I].

X3.7 Discharge planning

Discharge planning involves the patient, external lay and professional carers, the multidisciplinary hospital and community team and the patient's regular GP. It should commence on admission and be documented within 24–48 hours (See Box 15 ). Appropriate patient education and attention to preventive management are likely to reduce the frequency of further acute exacerbations. Assessment of social supports and domestic arrangements are critical in discharge planning.

A discharge pack, which includes general information about COPD, advice on medication use and written instructions on use of inhalation and oxygen devices, if appropriate, as well as a plan for management of worsening symptoms, should be provided. The GP (and respiratory outreach program, if available) should be notified during the patient's admission. A case conference involving the multidisciplinary team and GP may assist successful transition to the community. Medicare Benefits Schedule Enhanced Primary Care item numbers may be claimed for "participation in a case conference" and "contribution to a care plan" (see Section D).

Before discharge, referral to a comprehensive pulmonary rehabilitation program should be considered.

X3.8 Support after discharge

Follow-up at home after discharge from hospital may extend the continuum-of-care process begun within the acute environment, although evidence supporting benefit from from nurse-led chronic disease management for people with COPD is absent²⁸⁵ [evidence level I]. Telephone follow-up may be a way of systematically extending support to patients and increasing their coping strategies at home, but the outcomes of this intervention have not been studied systematically.

An integrated approach involving a discharge plan shared with the primary care team together with access to a case manager through a web-based call centre has been shown to reduce re-admissions for COPD exacerbations compared to usual care ²⁸⁶(evidence level II). This trial was conducted in Europe and the applicability to other settings is not known.

X3.9 Clinical review and follow-up

There are no randomised clinical trials that have addressed the best method for follow-up.²⁸⁷ It is recommended that the first review after a hospital admission should be by the GP and within seven days of discharge (Box 16). A decision about the requirement for specialist review should be made at the time of discharge. Follow-up care allows further discussion of self-management plans and future monitoring.²⁸⁷