Introduction

Intensive care units (ICUs) were originally developed more than 50 years ago to offer patients prolonged respiratory support. Of course, more recently there have been great advances in the support of other organs. Nevertheless, ventilation and its accompanying airway management techniques remain at the centre of intensive care practice.

Endotracheal intubation

Indications for intubation

Respiratory failure is the main indication for endotracheal intubation in the ICU. However, there are other indications, including: control of partial pressure of carbon dioxide (PaCO2) in head injury patients, airway protection (e.g. during endoscopy), to allow investigations (e.g. bronchoscopy, computed tomography or magnetic resonance imaging scan), for transfer to another hospital or for uncontrolled seizures. Haemodynamic instability due to septic or cardiogenic shock is also an under-recognized indication for intubation.

Decision to intubate in respiratory failure

The decision to intubate should be primarily made on clinical grounds and the figures in Table 25.1 should be used as a guideline only. As an example the patient with chronic neurological weakness managed with nocturnal bilevel positive airway pressure (BIPAP) may normally have a (PaCO2) of 8.0 kPa and would almost certainly not require intubation. However, a young asthmatic patient who is deteriorating rapidly despite aggressive treatment may require intubation with a (PaCO2) of only 7.0 kPa. In general terms consideration should be given to the underlying diagnosis, the possibility of improvement with intensification of treatment, the trend in the clinical picture and most importantly whether the patient is tiring.

Organizational factors such as the availability of skilled support and the time of day are also often important considerations. Respiratory function and the ability to observe changes in respiratory function are decreased at night.