Agitation and sedation

Give some causes of acute confusion in the postoperative patient

1. • Pain, anxiety and disorientation can all commonly occur in patients in intensive care.

2. • Sepsis: systemic infection, or localized to chest, urinary tract, wound, etc.

3. • Hypoglycaemia, or hyperglycaemia with ketoacidosis.

4. • Respiratory failure, leading to hypoxaemia or hypercarbia: precipitating causes apart from chest infection include acute pulmonary oedema, pneumothorax, pulmonary embolism and sputum retention or atelectasis.

5. • Hypotension of any cause: e.g. bleeding, myocardial infarction, or arrhythmia leading to reduced cerebral perfusion.

6. • Acute renal or hepatic failure.

7. • Electrolyte disturbance: most commonly hypo- or hypernatraemia.

8. • Water imbalance: both dehydration and fluid overload.

9. • Acute urinary retention, especially in the elderly.

10. • Drugs: opiate analgesia, excess sedative drugs, anticholinergics.

Which investigations should you perform?

A full history and examination must be carried out so that the most pertinent investigations are performed. These investigations include:

1. • Arterial blood gas analysis: this determines the base excess and respiratory function,

2. • Serum glucose,

3. • Full blood cell count,

4. • Serum electrolytes: sodium, potassium, calcium, phosphate, magnesium, lactate (strictly speaking, a metabolite), urea and creatinine,

5. • Liver function tests,

6. • Sepsis screen: blood cultures, wound swab, urine and sputum cultures,

7. • Radiology, such as a chest radiograph,

8. • Electrocardiogram (ECG), for arrhythmias and myocardial infarction.

What is the purpose of sedation in the critical care setting?

1. • Anxiolysis,

2. • Analgesia,

3. • Amnesia,

4. • Hypnosis.

Thus, there is a reduction in the level of consciousness, but with retention of verbal communication. There is much variability on which permutation of these effects individual agents produce.

Therefore, from a practical perspective in the intensive care setting, sedative agents are used to permit tolerance of endotracheal tubes, suctioning and other bedside procedures.