CRQ Paper 4 Flashcards
Question 1. Anita, a 30-year-old woman, collapses at work following the onset of a severe headache. On arrival at the Emergency Department, she is confused, and her Glasgow Coma Score is 14 (E4V4M6). A CTbrain scan is performed, which shows intraventricular blood. A diagnosis of subarachnoid haemorrhage is made. a) List the three most common causes of blood in the subarachnoid space. (3 marks)
• Rupture of berry aneurysm 1
**AVM rupture and traumatic subarachnoid account for 10% each, with
aneurysm rupture accounting for 80% of
subarachnoid haemorrhage.
• Rupture of arterio-venous
malformation (AVM)
• Traumatic subarachnoid
haemorrhage (SAH)
b) List four risk factors associated with the development of aneurysmal subarachnoid haemorrhage. (4 marks
• Genetic
• Associated conditions, e.g.
polycystic kidneys
• Smoking
• Cocaine use
• Amphetamine use
• Ehlers–Danlos type IV
Any 4 Familial risk is significant
if a first-degree relative
has SAH.
Complete the labels (i–vi) on the following figure. (3 marks)
i = Anterior cerebral artery
ii = Anterior communicating artery
iii = Middle cerebral artery
iv = Posterior cerebral artery
v = Basilar artery
vi = Posterior communicating artery
At which three arteries are berry aneurysms most likely to occur? (3 marks)
• Anterior communicating artery
• Middle cerebral artery
• Posterior communicating artery
** Berry aneurysms occur at
bifurcations of major
arteries.
State two early and two late neurological complications of subarachnoid haemorrhage. (4 marks)
Early: Any 2
• Re-bleeding Aneurysms are coiled or clipped within the first few days to prevent re-bleeding.
**The highest risk period is 7–10 days following bleed.
• Seizure
• Hydrocephalus
Late: Any 2
• Delayed cerebral ischaemia/
vasospasm
**Nimodipine is taken for 21 days to reduce risk.
• Cognitive impairment
• Neurocognitive symptoms such
as fatigue, mood disturbance
• Hypopituitarism
**Neuropsychiatric symptoms are common
following SAH.
Question 2. Steven is a 2-day-old boy who has presented to the Emergency Department following a sudden collapse. He was born by normal vaginal delivery at 37 weeks without complication. a) A common cause of sudden collapse in a neonate is congenital heart disease.
State two other common causes. (2 marks)
• Sepsis
• Hypoglycaemia
• Metabolic/endocrine disorder
• Trauma/non-accidental injury
Any 2 The differential diagnosis of
collapse in a neonate is
broad.
This is a critical time
for the circulation: ductus
rteriosus closure may
unmask congenital heart
disease
b) List four clinical signs that are supportive of a diagnosis of congenital heart disease. (4 marks
• Tachypnoea and sweating whilst
feeding
• Persistent tachycardia
• Hepatomegaly
• Oedema of face/forearm/back/
legs
• Radio-femoral delay
• Cyanosis, especially on crying
• Pathological murmur
**A history of feeding difficulty is common.
Breathing and feeding cannot happen
simultaneously, so cyanotic episodes are often
precipitated by feeding.
NB features of the history are not
clinical signs
Steven’s mother describes a history of irritability and cyanotic spells when feeding and crying. Following examination, you suspect a diagnosis of tetralogy of Fallot. c) List the tetrad of features seen in this condition. (4 marks)
• Right ventricular outflow tract obstruction/pulmonary valve stenosis
• Ventricular septal defect (VSD)
• Right ventricular hypertrophy
• Overriding aorta
d) List two conditions associated with tetralogy of Fallot. (2 marks)
• DiGeorge syndrome
• 22q11 chromosome deletion
syndrome
• Down’s syndrome
• Cleft lip/palate
• Hypospadias
e) Other than feeding, list two other precipitants of a cyanotic episode (tet spell). (2 marks)
• Tachycardia
• Hypotension
• Defaecation
• Crying
f) Describe the physiological changes in cardiac blood flow that arise during a t⁸et spell. (4 marks)
• Tet spell is usually precipitated by
an acute decrease in systemic
vascular resistance (SVR)
• Or an acute increase in
pulmonary vascular
resistance (PVR)
• → Increased right-to-left shunt
across VSD
• → Decreased PaO2/increased
PaCO2, decreased pH
• → Tachypnoea
• → Increased negative
intrathoracic pressure
• → Increased venous return
• → Increased right-to-left shunt
across VSD
• → Vicious cycle
g) List twoways of managing thesecyanotic episodes in the period leading up to corrective surgery. (2 marks
• Administer oxygen
**The objective is to increase SVR, correct hypoxia and correct acidaemia.
Oxygen administration decreases PVR.
• Console child in knee–chest
position
** This is the equivalent ofthe older TOF child’s
squatting – increasing SVR.
• Opioids/ketamine/midazolam
** Relieves stress and hypercapnoea, but may decrease SVR.
• Correct any underlying cause,
e.g. arrhythmia, hypothermia,
hypoglycaemia
Question 3. You are asked to review Sangeeta in the Emergency Department, a 19-year-old woman with a history of insulin-dependent diabetes. She was found collapsed at home and was previously seen 48 hours ago. Her capillary blood glucose is 21.4 mmol/L. a) In the space below, list the criteria (in mmol/L) required for a diagnosis of diabetic ketoacidosis (DKA). (3 marks)
• Blood glucose > 11 mmol/L
(accept > 13.9 mmol/L)
** As per the Joint British Societies Group.
• Ketonaemia > 3.0 mmol/L
** (The American Diabetes Association has slightly different guidance.)
• Bicarbonate < 15.0 mmol/L
(accept < 18.0 mmol/L)
** A pH < 7.30 can be used inplace of bicarbonate in the diagnostic criteria.
List the pathophysiological changes that occur as a consequence of insulin deficiency which explain the biochemical findings of hyperglycaemia, ketonaemia, acidosis and glycosuria. (4 marks
Hyperglycaemia:
• Lack of insulin-facilitated
glucose uptake to muscles
• Increase in antagonistic
hormones (glucagon, cortisol,
growth hormone)
• Enhanced hepatic
gluconeogenesis and glycogenolysis
Ketonaemia:
• Enhanced lipolysis increases free
fatty acids
• Fatty acids undergo β-oxidation
into ketoacids
Acidosis:
• Ketoacids dissociate, releasing
hydrogen ions
• High anion gap metabolic
acidosis
Glycosuria:
• Plasma glucose concentration
exceeds capacity of proximal
convoluted tubule to completely
reabsorb glucose from filtrate
The results of her arterial blood gas are as follows: pH 7.17
PCO2 4.0 kPa PO2 12.1 kPa HCO3‾ <5 mmol/L Base excess −19.2 mEq/L K+ 7.8 mmol/L 40 Na+ 129 mmol/L
c) Based on the arterial blood gas results above, what would be your immediate management? (1 mark)
• 10 mL of 10% calcium gluconate
• 10 mL of 10% calcium chloride
(accept 10–20 mL)
Immediate management
also includes 50 mL of 50%
dextrose together with 10
units of soluble insulin.
d) List the ECG changes that may be seen with hyperkalaemia. (5 marks)
• Peaked T waves
• Prolonged PR segment
• Loss of P-wave
• Prolonged QRS complex
• ST-segment elevation
• Ectopic beats and escape rhythm
• Widening of QRS complex
• Sine wave
• Ventricular fibrillation
• Asystole
• Axis deviation
• Bundle branch block
* A vast array of ECG changes may be seen in hyperkalaemia. They are
normally classified as mild
(5.5–6.5 mmol/L), moderate (6.5–7.5 mmol/L), and severe (>7.5 mmol/L),
although classifications
vary.
** Calcium reduces the
excitability of cardiomyocytes, reducing
the risk of fatal arrhythmias.
e) List four other serious complications of DKA. (4 marks)
• Hypokalaemia
• Hypoglycaemia
• Renal impairment
• Cerebral oedema
• Pulmonary oedema
• Death
** Insulin administration may
cause hypokalaemia and
hypoglycaemia. Fluid
administration has been
postulated to cause cerebral
and pulmonary oedema
f) List the three endogenous ketone bodies. (3 marks)
• 3-β-hydroxybutyrate
• Acetoacetate
• Acetone
** The predominant ketone in
the body is 3-β- hydroxybutyrate, which is
measured in point-of-care testing.
Question 4. Diego, a 3-week-old boy born uneventfully at term,is brought by his mother tothe Emergency Department with progressively worsening non-bilious vomiting, usually directly after a feed.
a) On assessment, Diego is severely dehydrated. List four clinical signs consistent with this class of dehydration. (4 marks)
• General condition: abnormally
sleepy/lethargic
• Anterior fontanelle: markedly
sunken/depressed
• Weak rapid pulse
• Rapid respiratory rate
• Urine output: <0.5 ml/kg/h
• Skin turgor: decreased with tenting
• Mucous membranes: very dry
• Eyes: markedly sunken
** Dehydration is classified in
the context of fluid loss as a
percentage of body weight.
Mild = 5%
Moderate = 10%
Severe = 15%
The classification can help
guide fluid resuscitation.
Avenous blood gas is taken, giving the following results:
pH 7.61
PCO2 7.2 kPa
PO2 11.0 kPa
Base excess +30.1 mmol/L
Na+ 136 mmol/L
K+ 3.0 mmol/L
Cl‾ 72 mmol/L
b) Interpret the venous blood gas. (1 mark)
Hypokalaemic, hypochloraemic
metabolic alkalosis
(NB must state all three components
for the mark)
1 Whilst PCO2 is raised,
which may represent partial
respiratory compensation,
conclusions cannot easily
be drawn due to this being a
venous rather than an
arterial blood sample.
Onthe basis of the history and blood gas, you suspect a diagnosis of pyloric stenosis. c) List four risk factors for developing pyloric stenosis. (4 marks)
• More common in boys
• Young maternal age
• Maternal family history
• Infants born in autumn and
spring
• Maternal smoking
• Postnatal erythromycin
• Association with bottle feeding
4:1 male:female ratio,
especially common in first-
born boys.
d) List two additional features of the clinical examination consistent with a diagnosis of pyloric stenosis. (2 marks)
• Visible peristalsis
** Crossing abdomen from left
to right.
• Olive-like 2–3 cm palpable mass
in right side of epigastrium
**This clinical sign is less
frequently found due to
earlier diagnosis using
ultrasound
) List two hormones secreted as a direct response to severe dehydration. (2 marks)
• Antidiuretic hormone (ADH)
** By the hypothalamus/posterior pituitary in response to increased
plasma osmolarity.
• Renin
** Secreted in response to decreased tubular filtrate flow rate or decreased
perfusion of the macula densa
Despite the raised plasma pH, Diego’s urine is found to be acidic. f) Which hormone is responsible for this paradox? (1 mark)
Aldosterone
** Acts at principle cells in the
DCT and collecting ducts to absorb water and Na+ in
exchange for K+ and H+. In severe dehydration, the
conservation of water takes precedence over
normalising plasma pH.
After 48 hours of intravenous rehydration, Diego’s venous gas has normalised. The surgeons would like to perform a pyloromyotomy. g) List six intra-operative and post-operative considerations specific to this age group and procedure. (6 marks)
• Risk of aspiration on induction, but rapid sequence induction/ cricoid pressure difficult in this age group
• Nasogastric or orogastric tube insertion and ‘four quadrant’ aspiration I.e. aspirating the tube with
the infant supine, left lateral decubitus, prone and
right lateral decubitus.
• Use a 3.5 mm cuffed or uncuffed endotracheal tube
• Temperature control: increase the theatre ambient temperature to 26°C, use radiant heaters/forced air warmers
• Analgesia provided using local anaesthetic techniques and paracetamol
• Maintain normoglycaemia in the perioperative period: use of glucose-containing maintenance fluid
• Apnoea monitoring in a high-dependency environment
Mandatory for infants < 44 weeks post-conceptual age, or for ex-premature infants < 60 weeks post post-conceptual age.
• Reduced IV paracetamol dose: 7.5 mg/kg every 6 hours for post-conceptual age 36–44 week
Question 5. Siobhan presents to the Emergency Department with a short history of painless vaginal bleeding. She is 38 weeks pregnant and is visiting family in England. She remembers being told about a low-lying placenta but has been unable to attend any follow-up antenatal clinics.
a) Describe the four grades of placenta praevia by their relationship to the internal cervical os. (4 marks)
Grade 1: does not abut the internal
cervical os/low-lying
* Placenta praevia has also
been classified as minor or
major.
Grade 2: reaches margin of internal
cervical os/marginal
** Only 10% of those with a low-lying placenta at the20-week scan will go on to
have placenta praevia.
Grade 3: partially covers internal os/partial
Grade 4: completely covers internal
cervical os/complete
b) Aside from a low-lying placenta, list five risk factors for placenta praevia. (5 marks)
• Previous placenta praevia
• Previous termination of
pregnancy
• Multiparity
• Advanced maternal age (>40
years)
• Smoking
• Deficient endometrium –
scarring, endometritis, manual
removal of placenta, curettage,
fibroid
• Assisted conception
• Previous caesarean section
** In women who have
previously had a caesarean
section, 50% of those with a
low-lying placenta at 20
weeks’ gestation will go on
to have placenta praevia.
Following ultrasonography, Siobhan is told that her placenta is anterior and in a position that rules out normal vaginal delivery. Her observations are normal and her symptoms have now subsided. A decision is made to perform a caesarean section.
c) How may your anaesthetic differforthis procedure when compared to that of a low-risk elective caesarean section? (7 marks)
• Senior input – consultant
anaesthetist
• Additional monitoring – arterial
line
• Additional large bore
intravenous access
• Regional anaesthesia (must
qualify association with reduced
blood loss)
** Women with a placental
edge < 2cm from the
internal os are likely to be
delivered by caesarean
section. If uncomplicated,
this is usually after 38
weeks’ gestation.
• Consider general anaesthesia, or
consent for rapid conversion
• Cell salvage
• Cross-match
• Rapid infusor
• Tranexamic acid
• Consent for blood transfusion
In women with a history of
caesarean section and an
anterior low-lying placenta,
the risk of placenta accreta
should be considered.
Abnormal placental adherence describes the degree to which there is an invasion of chorionic villi into the myometrium because of a defect in the decidua basalis. d) List the three forms of abnormal placental adherence (3 marks) in order of increasing incidence. (1 mark)
Least common: placenta percreta 1
Intermediate: placenta increta 1
Most common: placenta accreta 1
Correct order of increasing incidence 1
Question 7. Kevin, a 32-year-old man, is listed for excision of a parathyroid adenoma under general anaesthesia. The parathyroid adenoma was discovered following a series of investigations to identify the cause of Kevin’s hypercalcaemia.
a) List six clinical features of hypercalcaemia. (6 marks)
The classical description of ‘stones, bones, abdominal
groans and psychic moans’ is rarely seen, with the
majority of patients having few symptoms on diagnosis.
• Bone pain
• Muscle weakness, reduced reflexes
• Fatigue
Gastrointestinal:
• Constipation
• Anorexia
• Nausea and vomiting
Renal:
• Polyuria resulting in dehydration
• Renal stones
The mechanism of polyuria
is nephrogenic diabetes
insipidus secondary to
nephrocalcinosis.
Neuropsychiatric:
• Depression/anxiety
• Cognitive dysfunction:
confusion, psychosis
• Insomnia
Depression is common, up
to 40% of patients are
affected.
c) Whichinvestigation is used to locate the parathyroid adenoma pre-operatively? (1 mark)
Technetium-99 m-sestamibi
scintigraphy
A diagnosis of oesophageal perforation is made and an open oesophageal repair via a thoracotomy is planned. c) State two considerations that may affect your drug choices during induction of anaesthesia. (2 marks)
• Sepsis is likely with potential for haemodynamic instability –consider use of cardiostable induction agent, e.g. ketamine
• Rapid sequence induction is indicated, but suxamethonium Increases intragastic pressure – use rocuronium
The use of cricoid pressure (which may increase the risk of exacerbating mediastinal contamination through coughing/straining) must be balanced against the risk of soiling
lungs.
The procedure is difficult, and intra-operatively, the patient spends 8 hours in the lateral position. f) List six complications of prolonged lateral positioning in this case. (6 marks)
• Displacement of double-lumen
endotracheal tube
** A fibre-optic scope should be immediately available, and the DLETT position checked following any patient repositioning.
• V̇ /Q̇ mismatch and shunt, leading
to hypoxaemia
• Radial nerve palsy in superior arm
**The radial nerve is
particularly at risk if the arm is abducted > 90°; an axillary roll is used to prevent mid-humeral radial nerve compression.
• Common perineal nerve palsy in
the inferior leg
** Due to compression between the fibular head and the operating table.
• Saphenous nerve palsy of
either leg
** A pillow is usually placed between the knees to prevent this complication.
• Brachial plexus injury
** The neck must be in a neutral position to prevent brachial plexus stretch.
• Ear injury
**Ensure that the ear has not folded during positioning.
• Optic neuropathy
** The lower globe is at risk from external compression from the pillow in the
lateral position.
• Pressure injury to bony
prominences, e.g. iliac cres
Question 9. Sarah, a 42-year-old woman, is listed for a laparoscopic cholecystectomy. Her body mass index (BMI) is calculated as 45 kg/m2. a) In which category of obesity would she be placed? (1 mark)
• Obesity class III
** According to the WHO
classification of obesity 2014. This BMI would
previously have been classified as morbidly obese.
b) Outline the physical principles of magnetic resonance imaging. (4 marks)
• Hydrogen atoms are abundant within the body within water molecules
• Hydrogen atoms possess a property called ‘spin’
• When surrounded by a strong magnet, spin aligns with the magnetic field
• Spin can be turned out of alignment with the magnetic
field by applying pulses of electromagnetic radiation
• The energy emitted is detected by three receiving coils, and translated into a series of grey pixels on a screen
* The three coils are positioned to generate a
three-dimensional image.
b) Whatare the distinguishing features of the following degrees of burn injury? (3 marks)
○ First-degree burn: red, painful, dry,
no blisters
** Only epidermis involved.
○ Second-degree burn: red, blistered,
painful, oedematous
** Epidermis and dermis involved.
○ Third-degree burn: white, painless,
no bleeding on pricking with a needle
○ Full thickness burn causing destruction of all skin layers plus underlying tissues.
c) The ED registrar states that the patient has burns covering an estimated 30% body surface area (BSA). How has she come to this conclusion? (2 marks)
• Wallace ‘Rule of nines’ (accept:
Lund-Browder chart)
• Chest/abdomen represents 18% BSA; one arm represents 9% BSA
*The adult head represents 9% BSA, whereas a child
has a proportionally bigger head (representing 18%
BSA) and smaller legs (representing 13.5% BSA
each)
e) List the three most common scoring systems in the United Kingdom for grading the severity of aneurysmal subarachnoid haemorrhage. (3 marks
Hunt andHess grading scale for subarachnoid haemorrhage (clinical)
WFNS=World Federation of Neurological Surgeons
•WFNS Gradingc Scale for Aneurysmal Subarachnoid Haemorrhage(clinical)
•Fisher grade (based on CT scan)
**There are many more scoring systems, but these three are byfar thecmost commonly used.
