Case Eight - Case Two Flashcards
what is the shock index
heart rate / blood pressure
what is a normal shock index and suggests that a patient is haemodynamically stable
a shock index of 0.5/0.7 is normal
if a patient is in shock, what treatment do they need asap?
500ml sodium chloride 0.9% IV over 10 mins
what is the pneumonic to remember the different categories of shock
‘how fast you fill the pump and squeeze’
fast - heart rate
fill - blood volume
pump - heart
squeeze - blood pressure
what are the fast (heart rate) problems
extreme tachycardia of any cause (e/g.ventricular tachycardia) or bradycardia
what are the fill (blood volume) causes
haemorrhage or dehydration (from inadequate intake or vomiting / diarrhoea) will both cause a reduced blood volume
what are the pump (heart) problems
a primary cardiac problem such as an acute MI, aortic dissection, papillary muscle rupture) or something preventing the heart’s ability to pump blood out of the thorax (pneumothorax or PE or CT)
what are the squeeze (BP) problems
sepsis and anaphylaxis both involve capillary dysfunction which causes fluid from the blood vessels to leak out into the tissues
what does the term shock describe
used to describe the state that results when circulatory insufficiency leads to inadequate tissue perfusion and thus inadequate oxygen delivery to tissues. this shortage of oxygen means that aerobic metabolism cannot occur, resulting in organ dysfunction
what are some of the broad categories of types of shock
hypovolaemic
distributive
obstructive
cariogenic
neurogenic
what suggests hypovolaemic shock
suggested by signs of shock plus history or examination evidence of bleeding or fluid loss, cool peripheries, a good response to fluid or blood resuscitation
what suggests distributive shock
may be suggested by signs of shock plus peripheral vasodilation i.e warm, dilated peripheries
there may be clues in the history like a recent infection that has been getting worse (sepsis) or a known exposure to an allergen (anaphylaxis)
the patient may be febrile. it may respond to fluid resuscitation, but as this is not the underlying cause, your patient may remain hypotensive
what is obstructive shock suggested by
signs of shock plus signs go a problem inside the thorax that is impeding cardiac output
what are the three risk factors for obstructive shock
tension pneumothorax
cardiac tamponade
massive pulmonary embolism
what is cariogenic shock suggested by
the history; the patient will usually have presented with adverse cardiac features like chest pain, syncope, or signs of heart failure; their peripheries may be cold; their ECG may give clues
what is neurogenic shock
a specific syndrome that happens in trauma. it is different to spinal shock
when does neurogenic shock happen
happens in high (cervical or high thoracic) spinal cord injuries where the patient loses their sympathetic outflow hence their normal sympathetic responses to blood loss
instead of tachycardic, they will be bradycardia
instead of hypotension and peripherally vasoconstrictor/cold, they will be hypotensive but peripherally dilated/warm
what is the most common cause of shock in trauma
haemorrhage
what is the most common type of shock overall
sepsis
what is the initial treatment for severe sepsis and hypovolaemia
IV fluid.
what is there management for an Acute Upper GI bleed
recommend a risk assessment using the Glasgow Blatchford Score to determine who is likely to benefit from early endoscopy
what haemoglobin should you aim for
70-100g/L
what is rnhabdomylosis
a syndrome whereby there is breakdown and necrosis of damaged skeletal muscle, releasing its contents into the circulation
what are the contents of this damaged skeletal muscle
electrolytes, myoglobin, sarcoplasmic proteins such as creatinine kinase
what can rhabdomyolysis cause
multiple complications, including AKI as the myoglobin deposits in and obstructs the renal tubules
what is anaphylaxis
a type I hypersensitivity reaction, which causes comprise to the airway, breathing and circulation, with or without skin or mucosal changes
it is a medical emergency which requires immediate recognition and treatment
A 25 year old woman has been unwell with vomiting and diarrhoea for six days. For the last 24 hours she has been vomiting even sips of fluid. Her temperature is 36.7, RR 20, sats 98% RA, HR 125, BP 85/54. Her lips and tongue appear dry and her hands and feet are cold. Her central cap refill time is 3 seconds. She is drowsy.
What is the most appropriate initial treatment?
The patient is dangerously dehydrated and showing signs of hypovolaemic shock; NICE guidance on IV fluids tells us that, for resuscitation, we should prescribe 250-500mL of a crystalloid IV STAT/ over less than 15 minutes
A 60 year old man was at a restaurant when he collapsed. His colleagues were very concerned about him because after eating his starter he started drooling and his tongue appeared to swell out of his mouth then he went very pale. His temperature is 37.0, RR 28, sats 95% RA, HR 140, BP 70/40. He is scratching his arms and trunk, but the rash that appears when he scratches doesn’t last long and seems to move.
What is the most appropriate initial treatment?
IM adrenaline 0.5mL 1:1000
why?
the patient is shocked and the features of tongue swelling causing airway compromise and pallor suggesting severe illness/hypotension, as well as features of an urticarial rash and a possible food exposure in a restaurant, suggests that his shock is due to anaphylaxis
what is the treatment of anaphylaxis
IM adenaline 500mcg or 0.5mL of 1:1000
we use 1:1000IM because it is more concentrated, thus a smaller amount can be injected into the muscle.
You are reviewing the bloods that were ordered during the morning ward round. A patient’s U&Es are as follows:
Na 134
K 6.7
Urea 30
Creatinine 400
eGFR 15.
What are the most appropriate initial actions?
ECG and prescribe IV calcium gluconate
why?
a potassium of 6.7 is dangerously high and so e should immediately review the patient, undertake an ECG, and protect the cardiac membrane with IV calcium.
this will usually be 10mls of 10% calcium gluconate IV over 10 minutes which is equivalent to 2.2mmol of calcium and can be repeated if the ECG has not improved.
After these initial life-saving actions have been undertaken, it would be appropriate to prescribe IV insulin-dextrose (usually 5-10 units of fast acting insulin in 50mLs of 50% glucose over 5-10 minutes) and nebulised salbutamol to drive potassium out of the serum and into the cells.
You are bleeped to review a patient on the wards who the nurses say is ‘triggering for sepsis.’ You review them, prescribe antibiotics, and take a venous blood gas.
pH 7.28 pCO2 5.5 pO2 12.0 Na 136 K 4.5 Cl 90 HCO3- 20 BE -4 lactate 4
Which is the most accurate interpretation of these results?
raised anion gap metabolic acidosis due to elevated lactate
Correct answer.
The pH of 7.28 shows an acidosis. However, blood gases may show several synchronous processes so don’t forget to work out the anion gap to confirm or refute the presence of raised anion gap metabolic acidosis. In this case, the acidotic pH is likely due to the addition of unmeasured anions or lactate. This is commonly due to hypoperfusion such as caused by sepsis or other causes of shock, but it can also be due to medications such as metformin or salbutamol
You are reviewing a 72 year old male patient in A&E. They have been referred by the Emergency Medicine ST5 as ‘chest sepsis’ and ‘fast AF.’ You go to see the patient to clerk them. When you undertake your review of systems, the patient tells you that they have not passed urine all day and you notice that their creatinine is 180 (eGFR 62), whereas at a routine blood test 3 weeks ago it was 100 (eGFR >90). Blood pressure is 120/65. Weight 80kg.
Which medication would be most appropriate to suspend?
Ramipril 5mg
Correct answer.
Ramipril (an ACE-inhibitor) has many long-term benefits for patients with certain chronic diseases. However, many patients with acute illness have hypotension, AKI, and hyperkalaemia. Ramipril has antihypertensive effects and it also reduces renal hyperfiltration which can reduce eGFR and increase potassium, all things we want to avoid in the acutely unwell patient. Hence, NICE advises us to temporarily suspend it in the setting of acute hypotension and AKI. Remember that many drugs are renally excreted. The patient’s apixaban and metformin prescriptions will need to be reviewed if the eGFR continues to drop.
what is the most immediately dangerous breakdown product in rhabdomyolysis
potassium
Hyperkalaemia can cause cardiac arrhythmias and cardiac arrest
what can this breakdown products in rhabdomyolysis cause
AKI
myoglobin in particular, is toxic in high concentrations. impaired renal function results in further accumulation of these substances in the blood
what are other complications of rhabdomyolysis
compartment syndrome and DIC
what can cause rhabdomyolysis
Prolonged immobility, particularly frail patients who fall and spend time on the floor before being found
Extremely rigorous exercise beyond the person’s fitness level (e.g., endurance events or CrossFit)
Crush injuries
Seizures
Statins
what are the signs and symptoms of rhabdomyolysis
Muscle pain
Muscle weakness
Muscle swelling
Reduced urine output (oliguria)
Red-brown urine (myoglobinuria)
Fatigue
Nausea and vomiting
Confusion (particularly in frail patients)
what is the crucial diagnostic blood test for rhabdomyolysis
creatine kinase
It is normally less than around 150 U/L. In rhabdomyolysis, it can be 1,000-100,000 U/L.
when does creatine kinase raise
typically rises in the first 12 hours, then remains elevated for 1-3days, then gradually falls.
the higher the CK, the greater the risk of kidney injury
what does myoglobinuria refer to
myoglobin in the urine
it gives urine a red-brown colour. a urine dipstick will be positive for blood
what investigations are required for AKI and Hyperkalaemia
urea and electrolytes
what are used to assess and monitor the heart’s response to Hyperkalaemia
ECGs
what is the management to correct hypovolaemia and encourage filtration of the breakdown products
intravenous fluids are the mainstay of treatment
what are the additional management options that are debatable and have associated risks
IV sodium bicarbonate (to increase urinary pH and reduce the toxic effects of myoglobinuria)
IV mannitol (to increase urine output and reduce oedema)
what is HOCM
hypertrophic obstructive cardiomyopathy is a condition where the left ventricle becomes hypertrophic.
where does this tend to affect
tends to asymmetrically affect the septum of the heart, blocking the flow of blood out of the left ventricle;e.
this is referred to as left ventricular outflow tract obstruction (LVOT)
what is HOCM associated with
increased risk of heart failure, myocardial infarction, arrhythmias and sudden cardiac death
who is it a notable cause of sudden cardiac death in
young people, including high-performing athletes
what kind of genetic condition is HOCM
autosomal dominant genetic condition resulting from a defect in the genes for sarcomere proteins. it occurs in about 1 in 500 people
what is the presentation of HOCM
most patients are asymptomatic
however, can present with non-specific symptoms:
Shortness of breath
Fatigue
Dizziness
Syncope
Chest pain
Palpitations
what do severe cases of HOCM present with
symptoms of HF
why is it important to ask about FH
ask about a family history of heart disease and sudden death. it may occur in patients without a family history if a de novo mutation occurs
what are the examination findings in HOCM
Ejection systolic murmur at the lower left sternal border (louder with the valsalva manoeuvre)
Fourth heart sound
§Thrill at the lower left sternal border
what may there also be signs of
Atrial fibrillation (irregularly irregular pulse)
Mitral regurgitation (high-pitched, pan-systolic murmur)
Heart failure
what are the investigations done for HOCM
an ECG - may show. left ventricular hypertrophy
a CXR is usually normal. it may show signs of pulmonary oedema if heart failure is present
an echocardiogram or cardiac MRI is used to establish the diagnosis
genetic testing may be considered to establish the affected genes
what is the management of HOCM
beta blockers
surgical myectomy
alcohol septal ablation
implantable cardioverter defibrillator
heart transplant
what are patients with HOCM to avoid
intense exercise, heavy lifting and dehydration
what medications are avoided in HOCM and why
ACE inhibitors and nitrates are avoided as they can worsen the LVOT obstruction
what are the outcomes of HOCM
Minimal symptoms and a normal lifespan (most patients)
Arrhythmias (e.g., atrial fibrillation)
Mitral regurgitation
Heart failure
Sudden cardiac death
what is dilated cardiomyopathy
condition where the heart muscle becomes thin and dilated. it may be genetic or seoncdary to other conditions such as myocarditis
what is alcohol-induced cardiomyopathy
a type of dilated cardiomyopathy causes by long term alcohol use
what is restrictive cardiomyopathy
when the heart becomes rigid and stiff, causing impaired ventricular filling during diastole
what is arrhythmogenic cardiomyopathy
a genetic condition where the heart muscle is progressively replaced by fibrofatty tissue. it becomes prone to ventricular arrhythmias. it is a notable cause of sudden cardiac death in young people
what is takotsubo cardiomyopathy
a condition with a rapid onset of left ventricular dysfunction and weakness
this often follows severe emotional distress, for example the death of a pattern
it is called broken heart syndrome
it resolves spontaneously with time
where are most pacemakers placed
In the right atrium and right ventricle
not placed in the atrium as there is too high flow condition
what are the indications for a pacemaker
Symptomatic bradycardias (e.g., due to sick sinus syndrome)
Mobitz type 2 heart block
Third-degree heart block
Atrioventricular node ablation for atrial fibrillation
Severe heart failure (biventricular pacemakers)
what is a biventricular pacemaker used for
leads in the right atrium, right ventricle and left ventricle
there are usually in patients with severe HF.
they coordinate the contraction of these chambers to optimise heart function
what is this refereed to as
cardiac resynchronisation therapy
what are ICD’s
implantable cardiverter defibrillators
what do ICDs do
continually monitor the heart and apply a defibrillator shock if they identify ventricular tachycardia or ventricular fibrillation
when are implantable cardioverter defibrillators used
in patients at risk of ventricular tachycardia or fibrillation, for example:
Previous cardiac arrest
Hypertrophic obstructive cardiomyopathy
Long QT syndrome
what can the pacemaker intervention be seen as on the ECG trace
seen as a sharp vertical line on all leads on the ECG trace
a line before each P wave indicated a lead in the atria
a lone before each QRS complex indicates a lead into the ventricles
what prosthetic valve has the smallest risk of thrombus formation
St Jude
