Description: Transient loss of consciousness (TLoC) is common and often leads to incorrect diagnosis, unnecessary investigation, or inappropriate choice of specialist referral. In August 2010, the National Institute for Health and Clinical Excellence published a guideline that addressed the initial assessment of and most appropriate specialist referral for persons who have experienced TLoC. The guideline focused on correct diagnosis and relevant specialist referral and did not make treatment recommendations. This synopsis describes the principal recommendations concerning assessment and referral of a patient with TLoC.
Methods: The National Clinical Guideline Centre developed the guidelines by using the standard methodology of the National Institute for Health and Clinical Excellence. A multidisciplinary guideline panel generated review questions, discussed evidence, and formulated recommendations. The panel included a technical team from the National Clinical Guideline Centre, who reviewed and graded all relevant evidence identified from literature searches published in English up to November 2009 and performed health-economic modeling. Both guideline development and final modifications were informed by comments from stakeholders and the public.
Recommendations: The panel made clear recommendations regarding the assessment of a person after TLoC, which emphasized the importance of clinical reasoning in diagnosis. Persons with uncomplicated faint, situational syncope, or orthostatic hypotension should receive electrocardiography but do not otherwise require immediate further investigation or specialist referral. Persons with features that suggest epilepsy should be referred for specialist neurologic assessment; brief seizure-like activity was recognized as a common occurrence during syncope that should not be regarded as indicating epilepsy. Persons with a suspected cardiac cause for TLoC or in whom TLoC is unexplained after initial assessment should receive specialist cardiovascular assessment. Guidance was provided on the appropriate choices of cardiovascular investigation, according to the presenting clinical circumstances.