Sudden Death Flashcards
(34 cards)
In the central dogma, which process is most likely to be affected by a mutation that changes the first base in an intron?
Splicing
Which genetic mutation is most closely linked with long QT syndrome?
Premature stop codon in exon 2 of a gene
How is QT interval corrected for heart rate?
(QT interval) / (sqr root R-R interval)
Which cardiac arrhythmia is most associated with long QT syndrome?
Torsades de Pointes
What is the most important piece of advice to give the parents of a newborn to prevent SUDI?
Put the newborn on their back to go to sleep
What is the major drug class treatment for long QT syndrome?
Beta-blockers (e.g. atenolol)
What are the two types of post-mortem?
Hospital: consent required, less common, may be required for donation (e.g. Alzheimer's research) Procurator fiscal (coroner in England/Wales): legally required, no consent needed, used in suspicious circumstances
What are the eight reversible causes of cardiac arrest?
4 H’s: hypoxia, hypovolaemia, hypo / hyper-metabolic (e.g. K+), hypothermia
4 T’s: thrombosis, tension ptx, tamponade, toxins
Define shock.
A condition of inadequate perfusion to sustain normal organ function. O2 delivery or distribution is ineffective to meet metabolic demands
Name the main types of shock.
Hypovolaemic (haemorrhagic or non) Cardiogenic Obstructive Distributive (septic, anaphylactic, neurogenic) Cytotoxic
Describe the clinical features and arrow plot of cardiogenic shock.
- poor forward flow (hypotension, fatigue, syncope)
- back pressure (pulmonary oedema, raised JVP, hepatic congestion)
- reduced BP and CO
- increased HR and CVP/PWCP
Describe the causes of, and arrow plot of, hypovolaemic shock.
- haemorrhagic (GI bleed, postpartum haemorrhage);
- non-haemorrhagic (water - D&V, burns, renal disease)
- reduced CO, BP, CVP/PCWP
- increased HR
Describe the pathology, arrow plot and management of septic shock.
- endotoxin mediated capillary dysfunction
- increased CO, temp, and HR
- decreased BP, CVP/PCWP
- measure lactate as a marker of hypoperfusion BEFORE hypotension
- sepsis 6, fluids, vasopressor (NA)
Describe the pathology, arrow plot and management of anaphylactic shock.
- mast cell release of histaminergic vasodilators
- reduced CO, BP, CVP/PCWP
- increased HR
- adrenaline, antihistamine (chlorphenamine) + steroids
Describe the pathology, arrow plot and management of neurogenic shock.
- loss of thoracic sympathetic outflow
- decreased HR, CO, BP, temp, and CVP/PCWP
- vasopressors
Name the main causes of obstructive shock.
Cardiac tamponade, PE, tension ptx
What is the main cause and pathology for cytotoxic shock?
- Uncoupling of tissue O2 delivery and subsequent reduced mitochondrial uptake
- secondary to CN or CO poisoning
How do physiological parameters change as haemorrhagic shock worsens?
- blood loss increases
- HR increases
- BP decreases
- pulse pressure decreases
- RR increases
- urine output decreases
- CNS/mental status deteriorates
Name and describe the four main compensatory mechanisms of hypovolaemic shock.
- baroreceptor reflex (carotid sinus CN IX; aortic arch CN X [reduces parasymp outflow, enhances symp])
- neurohormonal (adrenergic [adrenaline, NA], lactic acidosis [chemoreceptors], increased vasodilators in decompensated)
- capillaries (reduced hydrostatic pressure, inward net flow)
- renal (JGA release of renin, angio II -> H2O and Na reabsorption)
What is the difference between clinical and biological death?
Clinical death is reversible with resus; biological death is not
What is the name for the body’s resistance to defib current?
Transthoracic impedance, 25-180 ohms
Describe the management for shockable and non-shockable cardiac arrest.
Shockable (VF, pulseless VT) -> 3 shocks, adrenaline, amiodarone
Non-shockable (PEA, asystole) -> adrenaline every 3-5 min
Name the 6 steps of ECG interpretation.
- is electrical activity present?
- rate (= 300/R-R interval)
- is the QRS complex regular or irregular?
- is the QRS complex narrow or broad?
- is atrial activity present?
- is atrial activity related to ventricular activity?
What is the normal QT interval?
<440ms (11 small boxes)
>320ms (8 small boxes)
