Introduction
Management of ABD involves the following:
Identification
It is vital to identify ABD as a medical emergency in a timely fashion so that patients can be transported to, and managed within, a safe environment. This highlights the need for a multi-agency approach and requires the Police and Ambulance Services to have appropriate training.
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The key to managing this condition well is early recognition and identification of ABD and a clear understanding that it is a potentially fatal medical emergency.3
Control
Safety of the patient and other people is the first priority, and before a patient can be sedated they may need to be physically restrained, usually by police or others trained in restraint techniques. The level of force employed must be justifiable, appropriate, reasonable and proportionate to a specific situation. It should also be kept to the minimum of time possible as control techniques worsen acidosis and may increase the risk of death.
Initially, simple de-escalation techniques should be attempted, e.g. quiet area, familiar people, although these are often unsuccessful.
Medical management
Initial management should be initiated in a systematic ABC way as would be appropriate for any unwell patient.
- Oxygen therapy should be commenced if appropriate
- A brief history and examination should be undertaken to exclude any other obvious causes
- Commence cardiac monitoring/pulse oximetry/blood pressure monitoring as tolerated
- If it is safe to do so, attempt to obtain IV access
- Check blood glucose
- Commence IV fluids
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The patient experiencing ABD may not tolerate some, if any, of these basic measures. The priority here will be to maintain the safety of the patient and those around them and so some of the above may have to be compromised until the patient has been adequately sedated to ensure undertaking them is safe.
Sedation
Sedation is key to managing agitation but also indirectly reduces the autonomic effects and acidosis caused by ABD and thus is vital and can be life-saving. However, if not done with caution, it can cause significant adverse effects. Patients with ABD may need large doses of sedative drugs.
There is no ‘ideal’ drug and there are no clear evidence-based protocols therefore treatment recommendations are mainly consensus driven. You should practice as per your Departmental Policy for sedation of agitated patients.
The Sedation Assessment Tool17 measures the degree of agitation based upon descriptors for responsiveness and speech. It may be used to guide the choice and technique of sedation required.
| SCORE | RESPONSIVENESS | SPEECH |
| +3 | Combative, violent, out of control | Continual loud outbursts |
| +2 | Very anxious and agitated | Loud outbursts |
| +1 | Anxious /restless | Normal / talkative |
| 0 | Awake and calm, co-operative | Speaks normally |
| -1 | Asleep but rouses normally if name called | Slurring or prominent slowing |
| -2 | Responds to physical stimulation | Few recognisable words |
| -3 | No response to stimulation | Nil |
RCEM1 recommends the use of ketamine or droperidol for rapid early control of acute behavioural disturbance. Both drugs can be given via the intramuscular route. Benzodiazepines may also be used but are associated with a higher rate of adverse events.
Use of a combination of benzodiazepines and haloperidol for psychotic patients has been shown to be more effective than use of a single agent. However, neuroleptic drugs may exacerbate certain symptoms of ABD and can potentially prolong the QTc in patients already susceptible to arrhythmias, therefore, antipsychotics such as haloperidol are best avoided, if possible, in ABD.18
Sedation should take place in an area capable of continuous measurement of cardiac rhythm and vital signs, as well as having resuscitation equipment readily available. In most EDs in the UK this is likely to be the resuscitation room.
Care must be taken not to automatically escalate treatment to Rapid Sequence Induction and intubation, as the patients tachypnoea is often protective against the severe underlying metabolic acidosis. Rendering the patient apnoeic may then acutely worsen the acidosis and lead to sudden death.
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Benzodiazepines are the most widely used drugs for initial sedation of ABD patients.3 Ketamine may be considered the first line agent as it causes less sedation than benzodiazepines and offers predictable sedation at a standard dose, however, physician familiarity with this drug may be less widespread. As the key to improving outcomes in cases of ABD is rapid sedation then the agent of choice will be that which the treating clinician is most comfortable using. In severe or refractory cases, patients may require rapid sequence induction and ventilation.