BLACKOUT Flashcards
Transient loss of conscious can be divided into
Syncopal and non syncopal
TYPES OF SYNCOPAL
Reflex
Vasovagal- Brady cardia, reduced perfusion, cerebral hypoperfusion. Pain, fear, straining.
Carotid sinus hypersensitivity
Situational syncope
Types of syncope
Cardiac
Arrhythmias- reduction in cardiac output
Structural pathology eg aortic stenosis
Massive pe
Types of syncope
Orthostatic *when he stand there is a drop in by, compensated by vasoconstriction. TO prevent a transient fall in by as this mechanism takes a few seconds there is an increase in HR. If a patient has a reduced intravascular volume eg from dehydration this response is blunted.
Dehydration
Drugs- anti htn, anti sums
Autonomic instability
Types of non syncopal transient loc
Intoxication eg alcohol sedatitives Head trauma Hypoglycaemia Non epileptic seizure Epileptic seizure Narcolepsy
MOST COMMON CASES OF LOC IN A 25 YEAR OLD
Vasovagal syncope
May have warning signs- calmly, sweating, pale, odd sensation in tummy, ear fullness
Most common cause of LOC in 55 year old
Vasovagal syncope or arrhythmia
Most common cause of loc in elderly
Orothsatic hypotension causes by meds
Diuretics - reduced blood volume and vasodilation
ACE- ‘’
b blockers- inability to increase HR
A blockers- inability to vasoconstriction
CCB- Inability to vasoconstrict
Epilepsy BEOFRE DURING AND AFTER
Before;
May have stereotypical aura or no warning
During;
Lasts minutes, incontinence, tongue biting, jerking, dropping, stiffening.
After;
Slowed recovery confused for 5-30minutes
Vasovagal before during after
Before;
Vagal symtptoms- sweating pallor, nausea, may be a precipitent
During
Lasts seconds, may be twitching or incontinence
After;
Rapid recovery on sitting/lying.
Arrhythmia before during and after
Before; No warning During Lasts seconds, may be twitching/ incontinence After Rapid spontaneous recovery
Past medical hx questions to ask after LOC
Previous episode Diabetes Epilepsy Cardiac illness PVD- claudication Anemia - hypoxia Psychiatric illness- panic attacks, non epileptic seizures
Drug hx after LOC
Insulin Oral hypoglycemics HTN Vasodilators Anti arrhythmias Anti depressants- hypotension Recreational drugs
Exam after LOC
Tongue- bitten - look at sides
Dehydration- dry mucous membranes, tachycardia, hypotension, decreased skin tugor
Head trauma- did it happen before/during/after LOC
Heart- rate, rhythm, jvp for cannon waves- complete heart block
Murmurs- aortic stenosis
Carotid brutish
BP- orthostatic hypotension. Lying down and within two minutes of standing. Drop in 20mm systolic or 10 diastolic on standing
Focal neuro signs- peripheral neuropathy, Parkinson’s. Full neuro recovery.
Investigations LOC
O2 says
Bloods- glucose FBC- anemia, U&E- electrolyte abnormality
ECG- BBB, short PR, long QT
Three main causes of aortic stenosis
Young patient- biscuit aortic valve
Elderly- calcification of aortic valve
RF
Differential diagnosis sudden LOC in young- HOCM
Slow rising pulse is seen in aortic stenosis
LVH ECG
T wave inversion in lateral leads I aVL, V5-6
RVH ECG
T wave inversion leads V1-V3 II III aVF
Pulmonary embolism ecg
S1 Q3 T3
T wave inversion
Hypertrophic cardiomyopathy
Deep t wave inversion on all leads
RBBB
T wave inversion in right leads V1-3
LBBB
T wave inversion in lateral leads I aVL V5-6
Pulmonary hypertension
RVG- dominant r waves in v1 v2
RAD
P Pulmonslr peaked p- RAH
Right ventricular strain ST depression, t inversion V1-3
Status epilepticus
Emergency
Start with abc
High flow O2, continuous ECG, pulse oximetry and bp cuff, glucose cap, 2 Iv lines, send of FBC U&E Ca and Mg.
selective toxin screen and levels of AED’s may be appropriate
Benzodiazepines used to terminate seizure need own line.
If hypoglycaemic 20% dextrose 50mL.
D E
To end seizure
2-4mg of lorazepam IV as slow bonus over 2 mins
If fitting 10mins later, repeat.
If 10mins later and still fitting intensive care consult and give phenytoin infusion loading dose of 18mg/kg at a rate of 50mg/min. Monitor ecg and be for arrhythmias and hypotension.
Still fitting may need GA- thiopentone
Causes of status epilepicus
Poor compliancce with AED Metabolic causes- hypoglycaemia, electrolyte imbalance Alcohol or other toxins Hypoxia Infection Hypertensive encephalopathy
Complications of status epilepticus
Acute- hyperthermia, pulmonary oedema, arhtthmias and cardiovascular collapse
First degree heart block
Slowing down of signal from atrium to ventricle. Longer PR >200ms interval. Due to damage of AV node ; ischemia, inflammation, fibrosis
Second degree heart block
Some not all atrial contractions are transmitted to the ventricle.
Mobitz type 1; progressive lengthening of PR interval followed by miss QRS complex. Wenckebach pattern on ECG
Mobitz type 2; no warning by PR lengthening, random missed QRS- High risk it will progress to a complete heart block.
Third degree heart block
No CONDUCTION between atria and ventricles. Random P waves- very broad. Ventricles rely on escape beats- 40bpm.
Main side effects of AEDRUGS
Teratogenic
Sodium valproate- NTD
Phenytoin - cleft palate, congenital heart disease
Carbamazepine and phenytoin interfere with metabolism of contraceptive pill- should double dose/ use barrier. Can interfere with warfarin dosing.
SE of sodium valproate
Weight gain, hair loss, hair curling, nausea, rash, drowsiness, tremor, drug induced hepatitis.
Lamotrigine
Rash, SJS Headaches Dizziness Insomnia Vivid dreams
Carbamezipine SE
Rash Nausea Ataxia Diplopoda Agranulocytosis Hyponatraemia
Phenytoin side effects
Acne Rash Ataxia Opthalmoparesis Sedation Gingival hyperplasia
