Recognition of signs and symptoms in anaphylaxis

Recognition of signs and symptoms

To treat the condition successfully, it is essential to recognise the signs and symptoms of anaphylaxis. Systemic signs and symptoms that largely distinguish the patient with anaphylaxis from those with severe allergy have already been described. Training programmes that educate the lay person, including parents and extended family, partners, teachers, nursery workers and patients themselves, have been found to be successful in imparting knowledge concerning recognition and treatment (Litarowsky et al 2004, Morris et al 2011).

Potential reasons for non-recognition and treatment of anaphylaxis may include (Brown 2006, RCUK 2008, Jevon 2010, Arnold and Williams 2011, Dunbar and Luyt 2011, Spickett and Stroud 2011, Caton and Flynn 2013):

• Failure of patients to appreciate the gravity of their symptoms until it is too late to auto-inject.
• Not having a written action plan for use in an emergency.
• Mistaken diagnosis.
• Failure of clinical staff to provide information needed to recognise an episode of anaphylaxis.

Emergency treatment

The use of adrenaline injectors is the recommended first-line treatment for suspected or confirmed anaphylaxis (RCUK 2008). The device is quick and easy to use, and there is little evidence to support concerns about permanent ischaemic damage when used inappropriately or injected in the wrong location, for example a digit (Simons et al 2010, Arnold and Williams 2011). It is recommended that where no other device is available, an out-of-date injector should be used rather than none at all, as long as no precipitates have formed in the solution (Edwards 2009).

Shortcomings of emergency treatment

• Despite the apparent ease of use and unequivocal guidelines for use of adrenaline injectors, there is evidence that medical staff are sometimes reluctant to prescribe these and patients or the parents or carers of young children do not give the treatment as promptly as necessary (Rosen 2006, Soller et al 2011, Mustafa 2012).
• Medical reluctance to prescribe has been ascribed to fear of patient misuse and misdiagnosis, a lack of staff confidence in providing the information concerning training the patient to use the device, and fear of potential cardio-toxic side effects (Rosen 2006, Soller et al 2011, Caton and Flynn 2013).
• Patients often forget how to use the auto-injector or do not use it promptly.
• Others do not have auto-injectors readily available on a consistent basis, or allow them to expire or degrade from improper storage (Arnold and Williams 2011, Dunbar and Luyt 2011, Mustafa 2012).

Recommendations for effective management of the condition in urgent and emergency care are that (NICE 2011):

• All urgent and emergency care staff should be competent in patient education concerning the use of adrenaline injectors. ‘Dummy’ injectors are available for such teaching purposes.
• All urgent and emergency care units should stock adrenaline injectors for patients who are being discharged home after an anaphylactic episode. All patients should have at least two auto-injectors in case one fails, if a repeat dose needs to be given or in the event of a biphasic episode.
• Urgent care and emergency departments should consider the development of a patient information leaflet to reinforce verbal advice.
• Patients should be directed to appropriate internet sites to reinforce information already provided, expand personal knowledge and remind themselves how to self-inject. These sites may also be useful for education of clinicians.
• All children and young adults with anaphylaxis should be admitted to hospital for observation.
• Since rebound or biphasic episodes occur predominantly within six hours, all adults should be made aware of this and observed for this period before discharge.
• All patients should be referred to an allergy specialist.

Learning points

1. Training programmes that educate the lay person, including parents and extended family, partners, teachers, nursery workers and patients themselves, have been found to be successful in imparting knowledge concerning recognition and treatment.
2. Potential reasons for non-recognition and treatment of anaphylaxis may include failure of patients to appreciate the gravity of their symptoms until it is too late to auto-inject, not having a written action plan for use in an emergency, mistaken diagnosis, and failure of clinical staff to provide information needed to recognise an episode of anaphylaxis.
3. The use of adrenaline injectors is the recommended first-line treatment for suspected or confirmed anaphylaxis because this device is quick and easy to use. It is recommended that where no other device is available, an out-of-date injector should be used rather than none at all, as long as no precipitates have formed in the solution.
4. Medical reluctance to prescribe has been ascribed to fear of patient misuse and misdiagnosis, a lack of staff confidence in providing the information concerning training the patient to use the device, and fear of potential cardio-toxic side effects.