This is an HTML version of an attachment to the Freedom of Information request 'Clinical guidelines for identifying posterior CVAs'.

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Guideline ID
Transient Loss of Consciousness
Approved by
Clinical Effectiveness Group
Date Issued
Review Date
 Ambulance Care Assistant 
 Paramedic (non-ECP)
Authorised Staff
 Emergency Care Assistant 
 Nurse (non-ECP)
 Student Paramedic 
 Advanced Technician 
Guidance (Green) - Deviation permissible;  
Apply clinical judgement
1. Scope
This guideline details the assessment and management of patients who 
experience a transient loss of consciousness. 
Background and Definitions
The presentation of patients with a transient loss of consciousness (TLoC) is 
relatively common, affecting up to half the population in the UK at some point 
in their lives. The episode is often described as a ‘blackout’ or ‘collapse’.
TLoC may be defined as spontaneous loss of consciousness followed by a 
complete recovery with no residual neurological deficit. 
There are various causes of TLoC, including cardiovascular disorders (which are 
the most common), neurological conditions such as epilepsy, and psychogenic 
attacks (Non-Epileptic Attack Disorders).
The National Institute for Health and Clinical Excellence (NICE) suggest that 
the diagnosis of the underlying cause of TLoC is often inaccurate, inefficient 
and delayed; there is huge variation in the management of TLoC. A substantial 
proportion of people initially diagnosed with, and treated for epilepsy, have a 
cardiovascular cause for their TLoC. 

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3. Guidance
The Flow chart in Figure 1 provides support to the decision making process and 
the development of an appropriate care plan.
Figure 1 - Transient Loss of Consciousness Flowchart
Patient presents with Transient Loss of 
Conciousness (TLoC)
Determine if the patient has:
▲  a condition that requires immediate action
Convey to ED
▲  the person has sustained an injury as a result of TLoC
▲  they have not made a full recovery of conciousness
Record details about:
▲  circumstances of the event
▲  person’s posture immediately before loss of 
▲  pro-dromal symptoms (such as feeling warm or hot)
▲  appearance (for example, whether eyes were open or 
shut) and colour of the person during the event
▲  presence or abscence of movement during the event 
(for example, limb jerking and it’s duration)
▲  any tongue biting (record whether the side or the tip of 
the tongue was bitten)
▲  injury occuring during the event (record site and 
▲  duration of the event (onset to regaining conciousness)
▲  presence or absence of confusion during the recovery 
▲  weakness down one side during the recovery period
Confirm TLoC
1. Transient
2. Rapid onset
Unable to confirm - 
3. Short duration
Convey to ED
4. Spontaneous recovery
5. Any pallor with episode?
6. Ask patient - do you remember falling down?

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12 Lead ECG
Treat as a red flag if any of the following abnormalities 
Red Flag present 
are recorded on the ECG:

Convey to ED
 conduction abnormality e.g. complete right or left 
bundle branch block or any degree of heart block;
▲ a long or short QT interval;
▲ any ST segment or T wave abnormalities
Red Flag?
 ECG abnormality
▲  Heart failure (history or physical signs)
▲  TLoC during exertion
▲  Family history of sudden cardiac death under 40 
years and/or inherited cardiac condition
▲  New or unexplained breathlessness
▲  Heart murmur
▲  Anyone aged older than 65 years who has 
experienced TLoC without prodromal symptoms (such 
as sweating or feeling warm/hot before TLoC)
Can a diagnosis of uncomplicated faint or situational 
syncope be made?
Make a diagnosis of uncomplicated faint when:
▲  There are no features that suggest an alternative 
diagnosis AND there are features suggestive of 
uncomplicated faint such as (Three P’s):
▲  Posture - prolonged standing or similar episodes 
which have been prevented by lying down
▲  Provoking factors (such as pain or a medical 
Red Flag present 
Convey to ED
▲  Prodromal symptoms (such as sweating or feeling 
warm/hot before TLoC)
Make a diagnosis of situational syncope when:
▲ There are no features from the intial assessment 
that suggest an alternative diagnosis AND syncope 
is clearly and consistently provoked, for example, by 
straining during micturition usually while standing, 
coughing or swallowing.

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Patient Assessment
3.3.1  Assess the patient using a CABCD approach. Ask the person who has had the 
suspected TLoC, and any witnesses, to describe what happened before, during 
and after the event. Review past medical history, current medication, any recent 
changes and any issues in relation to medicines compliance.
3.3.2  Record the following details:
▲  Circumstances of the event;
▲  Person’s posture immediately before loss of consciousness;
▲  Prodromal symptoms such as sweating or feeling hot. A prodrome is an early 
symptom, or set of symptoms, that might indicate the start of the episode 
before specific symptoms occur;
▲  Appearance (for example, whether eyes were open or shut) and colour of the 
person during the event;
▲  Presence or absence of movement during the event (for example, limb-
jerking and its duration);
▲  Tongue-biting (record whether the side or the tip of the tongue was bitten);
▲  Injury occurring during the event (record site and severity);
▲  Duration of the event (onset to regaining consciousness);
▲  Presence or absence of confusion during the recovery period;
▲  Weakness down one side during the recovery period.
3.3.3  Record a 12-lead electrocardiogram (ECG). Treat as a red flag if any of the 
following abnormalities are found on the ECG: 
▲  Conduction abnormality (for example, complete right or left bundle branch 
block or any degree of heart block);
▲  Evidence of a long or short QT interval (see additional information sheet);
▲  ST segment or T wave abnormalities. 
3.3.4  Patients should be conveyed to an Emergency Department for specialist 
cardiovascular assessment following TLoC when any of the following are 
▲  ECG abnormality;
▲  Heart failure (physical signs, where this is not a pre-existing diagnosed 
▲  TLoC during exertion; 
▲  Family history of sudden cardiac death in people aged younger than 40 years 
and/or an inherited cardiac condition;
▲  New or unexplained breathlessness;
▲  A heart murmur (where this is not a pre-existing diagnosed condition).

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3.3.5  Consideration should also be given to conveying anyone aged older than 65 
years who has experienced TLoC without prodromal symptoms.
3.3.6  In the absence of any factors listed in Para 3.3.3, patients with any of the 
following should be referred for further cardiovascular assessment via their 
General Practitioner, where they are pre-existing diagnosed conditions and the 
patient is not currently compromised:
▲  Heart failure;
▲  Heart murmur.
Uncomplicated Vasovagal Syncope
3.4.1  Diagnose an uncomplicated vasovagal syncope (faint) on the basis of the initial 
assessment when there are no features that suggest an alternative diagnosis 
(note that brief seizure activity can occur during uncomplicated faints and is 
not necessarily diagnostic of epilepsy) and there are features suggestive of 
uncomplicated faint, such as the 3 P’s:
▲  Posture - Prolonged standing, or similar episodes that have been prevented 
by lying down;
▲  Provoking factors, such as pain or a medical procedure;
▲  Prodromal symptoms, such as sweating or feeling warm/hot before TLoC.
3.4.2  Situational syncope is a temporary loss of consciousness that is triggered by a 
specific situation. These situational triggers are diverse, and include having blood 
samples taken, straining while urinating or defecating and coughing. They can 
also be caused by heightened emotional stress, fear, or pain. When experiencing 
the trigger condition, the person often becomes pale and feels nauseated, 
sweaty, and weak just before losing consciousness. 
3.4.3  Situational syncope is caused by a reflex of the involuntary nervous system 
called the vasovagal reaction. The vasovagal reaction causes bradycardia and at 
the same time leads the nerves that serve the blood vessels in the legs to cause 
dilatation. The result is that the heart pumps out less blood, the blood pressure 
drops, and circulating fluid is drawn by gravitational forces into the legs rather 
than to the head. The brain is deprived of oxygen, and the fainting episode 
occurs.  Situational syncope is also known as vasovagal syncope.
3.4.4  If a diagnosis of uncomplicated faint or situational syncope is made, the 
patient does not have the red flags detailed in Para 3.3.4 and there is nothing 
in the initial assessment to raise clinical or social concern, no further clinical 
management is required.

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3.5 Epilepsy
3.5.1  The presence of one or more of the following features is strongly suggestive of 
an epileptic seizure:
▲  Bitten tongue; 
▲  Head-turning to one side during TLoC; 
▲  No memory of abnormal behaviour that was witnessed before, during or 
after TLoC by someone else;
▲  Unusual posturing; 
▲  Prolonged limb-jerking (brief seizure-like activity can often occur during 
uncomplicated faints); 
▲  Confusion following the event; 
▲  Prodromal deja vu, or jamais vu (the opposite to deja vu where a person 
momentarily does not recognise a word, person, or place that he or she 
already knows.  
3.5.2  The episode may not be related to epilepsy if any of the following features are 
▲  Prodromal symptoms that on other occasions have been abolished by sitting 
or lying down; 
▲  Sweating before the episode; 
▲  Prolonged standing that appeared to precipitate the TLoC;
▲  Pallor during the episode.
3.5.3  All patients suffering from their first seizure must be conveyed to an Emergency 
Department. The conveyance of confirmed epileptic patients following seizure 
must be based on the clinical presentation, the patients recent medical history 
and seizure pattern, their level of social support and consideration of capacity. 
The decision must be made in conjunction with the patient where they have 
Incident Closure
Patients who are not conveyed must be provided with a copy of the PCR and a 
patient information leaflet. The following information should be explained: 
▲  Explain the mechanisms causing their syncope.
▲  Advise on possible trigger events, and strategies for avoiding them. If the 
trigger events are unclear, advise people to keep a record of their symptoms, 
when they occur and what they were doing at the time, in order to 
understand what causes them to faint;
▲  Advise the person to take a copy of the patient clinical record, and the ECG 
where this can be printed, to their GP;
▲  Advise them to consult their GP if they experience further TLoC, particularly if 
this differs from their recent episode;

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The ambulance clinician should inform the patient’s GP about the episode using 
local mechanisms to do so. 
5. Documentation
5.1    In line with Trust Policy, a Patient Clinical Record must be completed and 
annotated appropriately to include the information detailed in Section 3. Any 
deviation from this guideline must be recorded, with any potential or actual 
adverse event reported through the incident reporting system.
6. References
National Institute for Health and Clinical Excellent (2011) Clinical Guideline 
CG109: Transient loss of consciousness in adults and young people. NICE.