Cardiac Flashcards

1
Q

Formula for ppoFEV1?

A

Pre-operative FEV1 x (19-number of segments to be resected)/19

Pre-op FEV1 x (remaining segments/total functioning segments)

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2
Q

Constituents of CARDIOPLEGIA?

A

JCUH uses:

  • Potassium - 20mmol
  • Procaine
  • Magnesium
Potential for:
Calcium
Mannitol
Bicarbonate/Histadine
Aspartate
Glutamate
Adenosine
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3
Q

What dose of KCl in cardioplegia?

How does it work?

A

20mmol
Inactivates fast Na channels which decreases resting membrane potential preventing the upstroke of the cardiac action potential
Myocardium becomes un-excitable and arrests

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4
Q

What does calcium do in cardioplegia?

A

At a low dose - to reduce the amount available for contraction
Maintains cell membrane integrity

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5
Q

What does Magnesium do in cardioplegia?

A

Prevents loss from cells
Maintains role as enzymatic co-factor
Competes with Ca to decrease Ca induced contraction

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6
Q

Role of mannitol in cardioplegia?

A

Raises osmolality which means decreased tissue oedema

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7
Q

Role of Bicarbonate/Histadine in cardioplegia?

A

Offset metabolic acidosis caused by ischaemia

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8
Q

Role of Procaine in cardioplegia?

A

Decreases excitability/conduction/reduction of arrhythmia at reperfusion

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9
Q

Describe the route(s) of administration of cardioplegia solution

A
  1. Antegrade - cannula in aortic root/coronary ostium
  2. Retrograde - cannula in coronary sinus and perfuses backwards; may not reach RV well

Usually a bit of both every 15-20 minutes

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10
Q

Complications of cardioplegia?

A
  1. Direct damage to myocardium from cannulae
  2. Failure to attain widespread cardiac perfusion (e.g. RV)
  3. Myocardial oedema, haemorrhage and injury
  4. Incorrect composition
  5. Arrhythmias
  6. Fluid overload
  7. Reperfusion injury
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11
Q

What are the benefits of using blood cardioplegia vs crystalloid cardioplegia?

A
Blood has:
O2 carrying capacity [Hb is usually 5]; pO2 on L side of OHDC
H+ buffer
O2 free radical scavenging
Delivery of other nutrients
Reduced myocardial oedema
Improved micro vascular flow
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12
Q

When do you perfuse your coronary arteries?

A

Well, that depends… on L or R or if branch is supplying atrial or ventricular myocardium
Mainly during diastole for Left coronary arteries BUT some is throughout the cardiac cycle (e.g. RCA)

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13
Q

What is normal coronary blood flow?

A

250ml/min

Or 5% of CO

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14
Q

List 3 different types of resp and cardiac function tests for pneumonectomy

A

FEV1/PPOFEV1 >2L (or more than >30% PPO value); if <30%, need CPET
Diffusion capacity - DLCO >30%
CPET >11ml/kg AT
VO2 Max >20 ideally

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15
Q

List 3 lung protective strategies when doing OLV

A
Vt 6ml/kg of IDEAL body weight
Peak pressure <30cmH2O
FiO2 to keep SpO2 94-98%
Aim for normal PaCO2
Plateau pressure <24cmH2O
PEEP at 5cmH2O
Avoid hYPERoxia
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16
Q

What is the final test that is done (intra-op) to assess patient suitability for pneumonectomy?

A

Clamping of ipsilateral pulmonary artery: resulting in shunting of blood supply into non-operative lung
Done for ALL patients

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17
Q

What are the adverse physiological responses to pulmonary artery clamping that would make the team reassess whether to continue with pneumonectomy?

A

CVS instability or excessive rise in CVP

Hypoxia despite FiO2 1.0

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18
Q

List 4 possible post op complications SPECIFIC to a pneumonectomy

A

Arrhythmias - 40% develop AF
Post pneumonectomy pulmonary oedema
Broncho-pleural fistula
Cardiac herniation

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19
Q

Symptoms of severe AS?

A

Angina
Syncope
Shortness of breath

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20
Q

What specific cardiac investigations may be used to assess AS

A

ECHO - LV contractility
Angiogram - to assess need for grafting at the same time
ECG - for ischaemia or LVH

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21
Q

In SEVERE AS, what are the values for:

  1. Peak aortic flow velocity
  2. Mean pressure gradient
  3. Valve area
A
  1. 4m/s
  2. > 50mmHg
  3. 0.6cm2/m2/BSA

(Normal velocity of any blood flow in the body is 1m.s)

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22
Q

Describe the pathophysiological features of Aortic Stenosis

A
  1. Valve stiffens -> progressive decrease in aortic valve area
  2. Increased LV afterload
  3. Compensatory LV hypertrophy
  4. Early diastolic dysfunction
  5. Decreased compliance with increased LVEDP
  6. Late systolic dysfunction
  7. Decreased systolic contractility and SV
  8. Heart failure and ischaemia
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23
Q

List the haemodynamic goals for intraoperative management of AS

A
Avoid arrhythmias
Avoid tachycardia (maintain adequate diastolic time)
Maintain afterload (maintain normal to high SVR)
Maintain pre-load/euvolaemia
Maintain SpO2 >94%
Normothermia
Maintain Hb
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24
Q

List the ways in which Dilated Cardiomyopathy may present

A

Sudden death
Increasing shortness of breath/LV failure
Embolism

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25
Q

List the pharmacological treatments for DCM

A
Beta blockers
Diuretics
ACEi
Aldosterone antagonist
Anti-coagulants (as stasis in LV increases risk of LV clot)
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26
Q

List NON-pharmacological treatments for DCM

A

LVAD
ICD
L ventriculotomy
Heart transplant

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27
Q

List predictors of poor outcome in DCM patients undergoing surgery

A

LVEF <20%
Elevated LVEDP
LV hypokinesia
Non-sustained VT

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28
Q

What are the haemodynamic goals when anaesthetising a DCM patient?

A
Avoid arrhythmias
Avoid tachycardia
Maintain preload
Maintain afterload
Avoid myocardial depression
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29
Q

How would you achieve your haemodynamic goals for a DCM patient?

A
Choice of anaesthetic - regional vs GA
Control arrhythmias
Arterial line
Fentanyl heavy GA
Low dose peripheral vasoconstrictor infusion
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30
Q

Define Pulm HTN

A

PASP >25mmHg at rest
>30mmHg on exercise
(On R heart catheterisation)

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31
Q

List the 5 classifications of Pulmonary HTN

A
  1. Idiopathic PAH
  2. LV disease
  3. Lung disease
  4. VTE
  5. Misc - e.g. sarcoidosis
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32
Q

How does pulmonary hypertension cause R heart failure

A

Raised Pulm artery pressure requires increase from RV
RV hypertrophy
Increased O2 demand
RV dilates, decreasing contractility and output
L septal shift and decreased LV compliance

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33
Q

What drugs would you use to treat CHRONIC pulmonary HTN?

A

Prostacyclins - Flolan/iloprost
Endothelin receptor antagonists - Bosentan
Phosphodiesterase V inhibitors - sildenafil
Nitric Oxide
Calcium channel blockers

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34
Q

What factors increase PVR?

A
Hypoxia
Acidosis
Pain
Hypercapnea
Hypothermia
PEEP
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35
Q

What surgical options are there for Pulm HTN?

A

Lung transplant

Pulmonary endarterectomy for VTE

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36
Q

What is the normal innervation of the heart?

A

Vagus nerve - CN X

T1-T4 of spinal cord post-ganglionic cardiac accelerator fibres from cardiac plexus

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37
Q

List the alterations in physiology in the transplanted heart

A

Resting tachycardia due to loss of vagal tone
No response to DIRECT autonomic influence or drugs that act via ANS (e.g. atropine)
Absent rate response to baroreceptors - no Valsalva response/carotid sinus stimulation/hypovolaemia/light anaesthesia
Stimulated only through direct acting agents such as catecholamines
Absent sensory innervation - silent MI
SV is pre-load dependent, therefore need to maintain filling pressures
PPM or pacemaker wires will be present - avoid RIJ
No catecholamine stores in the myocardium = decreased response to ephedrine

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38
Q

What concerns do you have when anaesthetising a patient with a heart transplant for non-cardiac surgery?

A

Physiology - denervation of orthoptic heart
Defib/PPM presence
Problems with rejection
Complications of transplant - leaky valve/conduction defects
Immunosuppression and its complications
Infection
Difficult IV access
Close monitoring pre-, intra- and post-operative
ECG will show double P wave (?)
Risk of silent MI

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39
Q

What drugs are used for immunosuppression following heart transplant?

A

Steroids
Calcineurin antagonists - cyclosporin and tacrolimus
Antiproliferative drugs - MMF

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40
Q

What are the implications of immunosuppression for perioperative care of the patient with a heart transplant?

A

Renal impairment
Hepatic impairment
Need to ensure immunosuppression still delivered
Steroids require supplementation to account for stress response
Pre-op blood essential for renal function/LFTs
Strict asepsis
Abx prophylaxis
Dyslipidaemia
HTN
Diabetes
Calcineurin inhibitors enhance the effect of NMBD
Skin malignancy

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41
Q

List some long term health problems in the patient with a heart transplant

A
Chronic rejection
Renal impairment/failure
Hepatic impairment/failure
Skin malignancy
Diabetes
Infection
Sarcoidosis
Amyloidosis
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42
Q

What are the indications for pneumonectomy?

A

Trauma with uncontrolled haemorrhage
Bronchial carcinoma
Chronic infection - TB/fungal

Pneumonectomy is incredibly aggressive, so lobectomy is much preferred

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43
Q

List the central neurological complications of ON-PUMP cardiac surgery

A

Stroke
Post op cognitive impairment
Fatal brain injury
Seizures
Visual field defects
Focal spinal cord injury: paraplegia/spinal stroke
Type 1 = actual brain injury (e.g. stroke); Type 2 = delirium

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44
Q

List the peripheral neurological complications of ON PUMP cardiac surgery

A

Brachial plexus injury
Saphenous nerve injury
Phrenic nerve injury
Anterior intercostal nerve injury

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45
Q

What are the patient specific risk factors for the central neurological complications after cardiac surgery?

A
Older age >65
Female>male
Diabetes
LVSD
Previous CVA
AF
PVD - atheromatous aorta
Low CO state post op
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46
Q

What are the procedural factors for central neurological complications after cardiac surgery?

A

Valve surgery (multivalve>mitral>aortic replacement) +/-CABG
Re-do or emergency surgery
Cannulation of atheromatous proximal aorta
Intra-operative hyperglycaemia
Poor temperature control
Deep hypothermic circulatory arrest (when required for the surgery)

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47
Q

List the monitoring that could be used to reduce the incidence of POCD

A

Transcranial Doppler
NIRS
BIS
Cerebral oximetry

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48
Q

How can hypothermia be neuroprotective?

A

Reduce CMRO2 (7% decrease for every 1 degree fall)
Attenuates neuroinflammatory response
Reduce apoptosis
Inhibit free radical generation

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49
Q

List some methods to reduce the incidence of neurological complications

A

TOE checking for atheromatous aorta prior to cannulation
Use high quality line filters
Avoid hyperthermia
Avoid multiple cross clamp of aorta
Close glycaemic control
Maintain cerebral perfusion
Use NMDA antagonist (Mg, lidocaine) for pharmacological neuroprotection
Use alpha stat (which is default for adults anyway)

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50
Q

How do you confirm a (LEFT) double lumen tube is placed correctly?

A

Insert the DLT to the L side
Attach Y connector
Sealing caps closed
Inflate tracheal cuff - ventilate both lumens and check for CO2 etc
Ventilate via endobronchial lumen by occluding tracheal lumen of Y connector; listen for air leak when you have opened cap on tracheal side and deflated tracheal cuff (check CO2, chest movement/auscultation)
Ventilate via tracheal lumen by occluding the bronchial lumen of Y connector; listen for air leak (after opening cap of bronchial lumen)/observe chest movement/auscultate

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51
Q

What may be different with a right sided DLT?

A

Need to think about the RUL and having an eye to ventilate the RUL

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52
Q

Outline the possible complications associated with the use of double lumen tubes

A
Damage: anything that gets in the way…
Teeth/lips/tongue/pharynx/trachea/carina/palate
Arytenoid cartilage & cords
Eye
Mucosal sloughing
Hypoglossal and lingual nerves
Oesophagus
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53
Q

What size DLT would you use in a man? A woman?

A

39 for men

37 for women

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54
Q

Name some complications from using a DLT

A
Failure to ventilate
Diffuse fibrosis of glottis
Emphysema (subcutaneous)
Pneumothorax
Endobronchial aspiration
Laryngeal obstruction
Vocal cord paralysis
Submucosal haemorrhage
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55
Q

What can you use if you cannot get the DLT in place?

A

Single lumen tube and bronchial blocker

Use fibreoptic scope to check placement of bronchial blocker

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56
Q

How would you manage the development of hypoxaemia during OLV?

A

Increase FiO2 to 1.0
Inform the surgeon
Apply PEEP/adjust PEEP to ventilated lung
Oxygen insufflation to non-ventilated lung (without using PEEP etc)
Ventilate both lungs/intermittent two lung ventilation
Optimise cardiac output
Optimise Hb

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57
Q

What factors can lead to the development of high airway pressures during OLV?

A

Bronchospasm
Obstruction of the ETT by sputum/blood
Malposition of DLT (e.g. missing out RUL) - use scope to reposition
Malposition of bronchial blocker - use scope to reposition
Pneumothorax of ventilated lung

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58
Q

How do you treat hypoxaemia due to shunt in pneumonectomy?

A

Increase FiO2
Optimise ventilator settings
Oxygen insufflation to non-ventilated lung
CPAP with O2 to non-ventilated lung
PEEP to ventilated lung
Increase Cardiac Output (improves mixed venous O2 saturation)
Intermittent 2 lung ventilation
Encourage early clamping of pulmonary artery to non-ventilated lung (during planned resection)

59
Q

What are the ABSOLUTE indications for one lung ventilation?

A

Prevent contamination of healthy lung - abscess, empyema, haemorrhage

Control distribution of ventilation - BP fistula, traumatic bronchial disruption

Facilitate single lung lavage - Cystic Fibrosis

60
Q

Compare and contrast DLT, bronchial blocker and single lumen tube

A

DLT
+quick to place; CPAP to operative lung; alternate OLV; suction/bronchoscopy
-limited sizes; difficult to place in distorted anatomy; not good for post op ventilation; potential airway trauma

BB
+easy size selection; easy to use; post op ventilation possible by removal
-longer to insert; suction not possible; bronchoscopy of isolated lung impossible; slow and incomplete collapse of lung

SLT
+easier to place in altered anatomy/emergency
-difficult for left OLV; bronchoscopy/suction/CPAP all impossible to isolated lung

61
Q

For pneumonectomy, what FEV do you need?

A

> 2L

62
Q

If pre-op FEV1 <2L, what other test would you do and what result is needed for operation to be considered?

A

CPET
VO2 max
>15ml/kg/min

63
Q

What Activated Clotting Time is needed for:

  1. On pump CABG
  2. Off pump CABG
A
  1. > 480s or 4x baseline
  2. 250-300s

(Normal value is 70-120s)

64
Q

List some theoretical benefits of “off pump” CABG compared to on pump

A
Avoiding the complications of CPB…:
Reduced post op cognitive impairment
Reduced consumption of clotting factors
Reduced renal impairment
Reduced ARDS
Reduced air emboli

Reduced cross clamp/risk of emboli
Reduced transfusion
Reduced ICU stay duration

65
Q

List some causes of haemodynamic instability during ‘off pump’ CABG

A

Arrhythmia
Ischaemia from vessel anastomoses
Haemorrhage
Deep anaesthesia/low SVR
Surgical compression of great vessels
Manipulation of heart distorting annulus - causes MR/TR
Surgical equipment causing RWMAs/impaired filling

66
Q

List ways to minimise instability during “off pump” CABG

A
Adequate preload/filling
Maintain contractility
Inotropic support
Monitor/correct electrolyte abnormalities
Avoid hypothermia
Avoid acidosis
Use of shunt to minimise ischaemia
Good communication with surgeons and anaesthetic team
67
Q

Mitral stenosis: criteria

A
Valve areas:
Normal 4-6cm2
Mild 1.6 - 2.0cm2 (patient will be symptomatic)
Moderate 1-1.5cm2
Severe <1cm2

Pressure gradients:
Mild <5mmHg
Moderate 6-10mmHg
Severe >10mmHg

68
Q

Why is Mitral Stenosis so bad in pregnancy?

A

MS means LV underfilled
Changes in pregnancy (increased HR, increased CO/blood volume, decreased SVR) exacerbate pulmonary hypertension and congestion. Also reduce LV filling time
MS has fixed CO so any decrease in SVR will decrease coronary perfusion
AF will make this worse

If valve area <1.5cm2 then decompensation likely

69
Q

List the haemodynamic effects of an IABP on:

  1. Aorta
  2. Heart
  3. Coronary blood flow
A
  1. Decreased systolic pressure
    Increased diastolic pressure
  2. Decreased afterload
    Decreased preload
    Increased CO
  3. Increased coronary blood flow/perfusion
70
Q

What are the principles of IABP?

A
Balloon in descending aorta
Counterpulsation
Inflates during diastole
Deflates at early systole
Synchronised with ECG
71
Q

List some contraindications to IABP

A
AR
Aortic dissection
AAA
Aortic stents
Uncontrolled sepsis
End stage LV impairment with no recovery
Tachyarrhythmias
Severe PVD
72
Q

List 6 complications of IABP

A
Limb ischaemia
De-synchronisation with cardiac cycle (which will increase work of heart!)
VTE
Compartment syndrome
Aortic dissection
Occlusion of renal blood flow due to malposition
Cardiac tamponade
Balloon rupture
73
Q

What is the anaesthetic management of regurgitant murmurs?

A

Full
Fast
Forward

74
Q

Pacemakers:

What do the letters mean?

A

1: Chamber paced (V, A or D-Dual)
2: Chamber sensed (V, A, D)
3: Mode of response (Triggered, Inhibited, Dual)
4: Programmable functions
5: Anti-tachycardia factors

75
Q

Describe what each position of a pacemaker code denotes?

A
  1. Chamber paced (V/A/D)
  2. Chamber sensed (V/A/D/O)
  3. Response to sensing (I/T/D/O)
  4. Programmable functions (P/M/C/R/B/N/O)
  5. Anti-arrhythmic function (S/E/D)
76
Q

Describe what each position of an ICD code denotes

A
  1. Shock chamber (A/V/D/O)
  2. Anti-tachcardia pacing chamber (A/V/D/O)
  3. Tacharrhythmia detection (E/H)
  4. Pacemaker capability
77
Q

What features make up Lee’s Revised Cardiac Risk index?

A
Known Coronary Artery Disease
Diabetes REQUIRING INSULIN
History of CCF
History of CVA
High risk surgical procedure
Creatinine of >170
78
Q

Using Lee’s Revised Cardiac Risk Score, what are the % of complications for any operation?
E.g. Score 0 = …
Score 1 = …

A

Score 0 = 0.4% of major intra-operative cardiac event
Score 1 = 0.9% risk
Score 2 = 6.6% risk
Score 3 = 11% risk

79
Q

What factors affect myocardial oxygen supply?

A
Diastolic filling time
Coronary perfusion pressure
Arterial O2 content
Hb
Coronary artery diameter
80
Q

What factors affect myocardial O2 demand?

A

HR
Contractility
Ventricular wall tension
Afterload (accept SVR)

81
Q

How does GTN work in ischaemic heart disease? What dose would you start with?

A
Reduces LVEDP (reduced wall tension)
10-200mcg/min

By reducing wall tension, GTN reduces myocardial O2 demand and increases sub-endocardial O2 supply through increased coronary blood flow

82
Q

What class of drug is enoximone?

A

Phosphodiesterase III inhibitor

Prevents degradation of cAMP

83
Q

What ECG features may be present in a patient with AS?

A
LVH
L axis deviation
Heart block
ST depression/TWI in LATERAL leads
P wave enlargement
84
Q

What are the criteria for Infective Endocarditis?

A

Duke’s criteria:
Major:
- Positive blood culture with likely organism
- Positive ECHO showing intra cardiac abscess/oscillating mass/dehiscence of prosthetic valve
- Dehiscence of new valve

Minor:
- Fever >38
- IVDU or predisposing heart condition
- Vascular phenomena - emboli; Janeway lesions; mycotic aneurysm
- Immunological phenomena - GN; Osler; Roth
- Microbiological phenomena - BCs not typical
- Echo findings not meeting major criteria but suggestive

85
Q

What are the minor criteria for IE?

A

Fever
Predisposition - IVDU
Septic emboli/mycoptic aneurysm
ICH

86
Q

List 6 patient related factors that are used in the EUROSCORE2

A
Age >60
Female sex
COPD
Extracardiac arteriopathy
Neurological dysfunction/disease
Previous cardiac surgery
Raised Cr
Active endocarditis
Critical pre-operative state - history of VF/pulseless VT, IABP, CPR
87
Q

Which factors convey the highest risk in the EURO Score II

A

Ejection fraction <20%
Emergency salvage operation
Dialysis

88
Q

What is the EURO Score II used for?

A

In hospital mortality after cardiac surgery

Not so useful after 30 days

89
Q

What are the cardiac/operation related factors involved in EUROScore II?

A
NYHA
LV function
Recent MI
Pulmonary Hypertension
Urgency of surgery
Weight of the intervention - type of surgery (single CABG vs valves etc)
Surgery on thoracic aorta
90
Q

What is the greatest risk for CVA in patients undergoing on pump CABG?

A

Proximal aortic atheroma

HTN/prev CVA/IDDM/carotid bruit all increase risk but they are not procedure specific

91
Q

What medical devices/procedures interact with a PPM/ICD?

A
Radiofrequency ablation
Radiation therapy
ECT
TENS
Extracorporeal shock-wave lithotripsy
92
Q

What are the associations with tracheo-oesophageal fistula?

A
VACTERL
Vertebral
Anorectal
Cardiac
Tracheal
Esophageal
Renal
Limb

Trisomy 21, Trisomy 18, Pierre Robin, DiGeorge

93
Q

How would you manage a neonate born with trache-oesophageal fistula?

A

Insertion of orogastric tube- suction
Avoid bag mask ventilation
Gas induction and spontaneously breathing
Use muscle relaxant when cuff beyond defect

94
Q

Define preload

A

End diastolic ventricular wall tension

95
Q

Define afterload

A

Tension developed in ventricular wall during systole
Tension generated in order to eject blood during systole
Determined by SVR, ventricular volume, wall thickness and conditions that obstruct outflow

96
Q

Define MAP

A

Diastolic BP + 1/3rd pulse pressure

Average arterial blood pressure throughout cardiac cycle

97
Q

What is FTc?

A

Flow time corrected: duration of flow during systole corrected for heart rate
Normal = 330-360ms
Low = hypovolaemia or increased afterload
High = low afterload

98
Q

What is peak velocity in cardiac output monitoring?

A

Highest blood velocity during systole
Used as a surrogate for LV contractility
Normal value: 1m/s

99
Q

What are the indications for OFF PUMP cardiac surgery?

A
Atheromatous aortic disease precluding bypass
Previous CVA
Renal disease
Diabetes
Ventricular dysfunction
Advanced age
Chronic lung disease
100
Q

What ACT is needed for OFF PUMP surgery?

A

250 - 300s

Normal is 100s

101
Q

How can the risks associated with lung resection be quantified pre-operatively?

A

Measure FEV1 and DLCO
Calculate ppoFEV1 and DLCO based on anatomical calculation, V/Q scans or CT
—If >60% - all good
—if <60% but >40% - stair climb/shuttle walk
If poor performance - CPET (?or straight to CPET?)
CPET etc

102
Q

What factors influence coronary blood flow?

A

Under autoregulation between 60-160mmHg

—O2 demand
—Metabolic factors - high CO2, K+, H+, prostaglandins, adenosine or NO)
—HR - an increase in HR encroaches on the diastolic filling time
—Patency of coronary vessels (atheroma prevents dilation due to O2 demand, causing downstream ischaemia)
—Autonomic/neurogenic control (minor)
— Factors inherent to the circulation (aortic diastolic pressure — LVEDP; HR; CO; isovolumetric relaxation phase)
— Humoral factors (Angiotensin, T3/T4)

103
Q

What is the myocardial O2 extraction ratio?

A

80%

Compared to 25% in the rest of the body

O2 extraction of 30mls/minute in the resting heart

104
Q

What is the pathophysiology of pulmonary hypertension?

A

Pulmonary vasculature hypertrophies/fibroses and narrows vessels causing increased pressures

RV hypertrophies against increased afterload

LV failure from decreased volume reaching LV andinterventricular septal interdependence

Coronary perfusion to RV depends on perfusion pressure at aortic root - dependent on SVR

105
Q

What are the anaesthetic goals when anaesthetising a patient with pulmonary hypertension?

A

Avoid hypoxia
Avoid hypercarbia
Avoid acidosis
Avoid increasing PVR
Avoid large decrease in SVR or venous return
Avoid arrhythmias
Reduce venous shunt (alveolar recruitment)
Avoid hyperinflation of alveoli
Avoid hypothermia
Avoid volume overload
Avoid/decrease stress and sympathetic response

106
Q

What are the treatment options for pulmonary hypertension?

A

Medical:
—Calcium channel blockers
—Endothelin receptor antagonist (bosentan)
—Phosphodiesterase V inhibitor (sildenafil)
—Prostacyclin analogue (epoprostenol)

Surgical:
—Atrial septostomy
—Lung transplant
—Endarterectomy (if VTE)

Ancillary:
—O2
—Diuretics
—Digoxin

107
Q

What are the causes of LV hypertrophy?

A

Hypertension
HOCM

108
Q

What are the anaesthetic goals when anaesthetising a patient with HOCM?

A

Maintain SVR
Avoid tachycardia
Avoid arrhythmias
Maintain preload

Monitor - TOE

109
Q

What are the indications for One-Lung Ventilation?

A

Absolute:
—Ventilation control in surgery to major airways/bronchopulmonary fistula
—Isolation from infection/haemorrhage
—Whole lung lavage

Relative:
—Facilitate surgery: VATS, oesophagectomy, lobectomy, pneumonectomy

110
Q

What are the codes for a pacemaker?

A
  • Chamber Paced (0,A,V,D)
  • Chamber Sensed (0,A,V,D)
  • Response (0,I,T,D)
  • Rate Response (0,R)
  • Anti-tachycardia function (0,P,S,D)
111
Q

What pulmonary vasodilators are there?

A

Prostacylin (IV/neb) Flolan
—mimics endogenous pulmonary arterial prostacylin

Endothelin receptor antagonist Bosentan
—vasodilatation by antagonising endothelin

PDE inhibitors sildenafil
—inhibit breakdown of cGMP and sustains action of NO

112
Q

What features on ECHO/ECG for HCM?

A

Systolic anterior motion mitral leaflet
Septal hypertrophy
LV hypertrophy

Inferolateral Q waves
LVH criteria

113
Q

Management of HOCM?

A

Medical:
Beta blockers
Pacemakers

Surgical:
Myectomy
Septal ablation
Transplant

114
Q

Describe the coronary blood supply

A

5% of CO; 250ml/min blood
R&L circulations
RCA from R aortic sinus -> runs in AV groove -> gives off marginal artery before running posteriorly and forming posterior interventricular artery (PIVA determines dominance)
LCA from L aortic sinus -> gives off circumflex and anterior inverventricular artery; Cx runs around and anastamoses with RCA; AIVA runs downward and anastamoses with PIVA

RCA supplies electronics
LCA supplies pump

Venous drainage:
70% accompany the arteries; drain into R atrium via coronary sinus
Great/middle/small/oblique cardiac vein
The rest drains directly into cardiac cavity

115
Q

What are the causes of AF?

A
Cardiogenic:
—IHD
—Mitral valve disease
—Hypertension
—
Non-cardiogenic:
—Sepsis
—PE
—Hyperthyroid
—Electrolyte imblance (K/Mg)
116
Q

Indications for OLV?

A

Absolute:
—BPF
—Pulmonary haemorrhage
—Thorascopic procedures

Relative:
—Pneumonectomy
—Lung volume reduction surgery
—Upper lobectomy
—VATS
—Thoracic aortic aneurysm
—Oesophageal surgery
117
Q

Describe the physiology of OLV

A

—After induction, the lungs move down the compliance curve (paralysis of chest wall/diaphragm)
—Upper lobe is now better ventilated
—Lower lung is better perfused -> VQ mismatch (shunt in lower lung and dead space in upper)
—Situation worsens once upper lung is deflated, since there is no ventilation of upper lung but blood flow continues (increased shunt)
—HPV slowly improves this
—Patients with abnormal upper lungs may already have limited ventilation/blood flow; OLV may produce little disturbance

HPV reduced by volatile anaesthetic agent (but only if >1 MAC)

118
Q

What are the components of a pacemaker?

A

—Pulse generator
-Battery
-Electronic circuitry - silicon chip, output circuitry
—Pacing lead(s)

119
Q

What are the components of an ICD?

A
—Pulse generator
-Battery
-Electronic circuitry
-Capacitor
—Lead(s)
120
Q

What are the causes of reduced transfer factor/diffusing capacity?
What are the causes of increased?

A
  1. Anaemia
    Fibrosis/interstitial lung disease
    Alveolar destruction
    Pulm HTN
  2. Pulmonary haemorrhage
    Polycythaemia
121
Q

Which PH patients benefit from R heart catheterisation?

A

Group 1 (PAH)
Group 4 (chronic CTE)
To assess the severity of haemodynamic impairment and assess potential vasoreactivity

122
Q

How do you support the failing Right Ventricle?

A
  1. Optimise RV preload:
    —appropriate fluid; consider diuretic if significant TR
  2. Augment the RV:
    —milrinone strengthens RV contraction & reduces PVR
    —can also use dobutamine, adrenaline, levosimendan
  3. Reduce RV afterload:
    —reverse causes of HPV
    —inhaled NO, milrinone, prostacyclin
  4. Maintain systemic BP/coronary perfusion:
    —vasopressin (may also pulmonary vasodilate and improve PVR/SVR ratio); noradrenaline
123
Q

What effect do the following drugs have on the denervated heart?
1. Adrenaline
2. Noradrenaline
3. Dobutamine
4. Isoprenaline
5. Ephedrine
6. Atropine
7. Glcyopryrrolate
8. Digoxin

A
  1. Augmented
  2. Augmented
  3. Normal
  4. Normal
  5. Decreased
  6. No effect
  7. No effect
  8. No effect
124
Q

What are some absolute contraindications for lung transplant?

A

—BMI >35
—Malignancy within 5 years (except cutaneous or paediatric)
—Significant chest wall abnormality
—Uncontrolled extra-pulmonary disease
—Substance addiction or misuse within 6 months
—Smoking within 6 months
—Alcohol use - potentially
—Non-adherence to therapy etc
—Mental health unable to cooperate with transplant
—Absence of social support

https://nhsbtdbe.blob.core.windows.net/umbraco-assets-corp/29406/pol231.pdf

125
Q

What are some relative contra-indications for lung transplant?

A

—>60 years
—Poor rehab potential
—Burkholderia
—BMI >30
—Chronic infection with resistant bugs
—Osteoporosis - severe/symptomatic
—Mechanical ventilation
—Coronary artery disease
—Renal impairment eGFR<50=
—Poorly controlled DM with end organ damage
—Any other disease causing end organ damage
—Already on loads of steroids
—HIV, Hep B & C

126
Q

What types of ECMO are there?

A

Veno-venous: replaces respiratory function - oxygenation and removal of CO2

Veno-arterial: replaces cardiac and respiratory function - pump generates perfusion pressure

Arterio-venous: replaces respiratory function, but heart is the pump; good at removing CO2, less good at oxygenation

127
Q

Why do suspected endocarditis patients need a TOE?

A

Because TTE only detects vegetations about 50%
TOE sensitivity is between 90-100%

128
Q

What is a persistent left-sided superior vena cava and why is it important?

A

1 in 200 healthy people; more common if other cardiac defects
Majority empty into coronary sinus, so more at risk of arrhythmias; may bypass pulmonary system which puts at high risk of air embolism
Ideally use R side for lines etc, but usually possible to use L side with appropriate precautions; may be smaller diameter than R SVC so may not tolerate CVVH etc

129
Q

What is the pathological process in prolonged QT syndrome?

A

Blockade of the rapid K outward current in cardiac myocytes
(There are 2 rectifier currents allowing potassium efflux from cardiac myocytes - rapid & slow)

130
Q

What are the indications for VV ECMO?
What are the contraindications?

A
  1. Respiratory failure with:
    -adequate cardiac function
    -Murray score >3
    -pH <7.20 from hypercarbia

2.
Absolute:
-Severe heart failure/cardiogenic shock
-Severe CHRONIC Pulmonary Hypertension & RV Failure
-Ongoing cardiac arrest

Relative:
-Ventilated >7 days with high pressures/FiO2
-Severe immunosuppression (solid organ transplant recipients)
-CPR duration >30mins with no neurological recovery
-BMI <18

131
Q

What are the indications for VA-ECMO?
What are the contraindications?

A
  1. Cardiogenic shock causing:
    -persistent lactate >3
    -persistent cardiac index <2.2
    -end organ dysfunction
    -EF <30%
  2. Limited reversibility
    Peripheral arterial disease
    Aortic dissection precluding cannulation
    Aortic regurgitation
    Massive bleeding
    CVA within 6 months
    CPR >30mins
132
Q

What are the absolute contraindications to all forms of ECMO?

A

Life expectancy <12 months
Heart disease not suitable for transplant
Lung disease not suitable for transplant
Pulmonary HTN
Advanced malignancy
GvHD
BMT recipient within 9 months
Cachexia due to underlying progressive disease

133
Q

What are the common causative organisms for IE?

A

Staph >50% of the time (80% being S. aureus)
Strep
Enterococcus
Gram -ve rods (E coli, P aeruginosa)

134
Q

What are the guidelines for managing a secondary pneumothorax?

A

BTS guidelines
O2; can attempt aspiration if small
Small bore chest drain 8-14Fr
Refer to Respiratory
Refer to Thoracics if lung not expanded at 48 hours
—Surgical intervention - pleurectomy preferable
—Suction should be high volume/low pressure

135
Q

What is the innervation of the heart?

A

Extrinsic innervation from parasympathetic (CN X) and sympathetic inputs (T1-T4)
—Superficial cardiac plexus - terminates inferior to aortic arch
—Deep cardiac plexus - terminates posterior to aortic arch, anterior to carina, into 2 halves which supply RCA and LCA

136
Q

What are some causes of hypotension in the post cardiac surgery patient?

A

Hypovolaemia:
-bleeding - medical vs surgical

Ventricular dysfunction:
-stunning
-reperfusion injury
-hypocalcaemia
-metabolic

Vasoplegia:
-rewarming
-anaphylaxis

Tamponade
Graft failure
Arrhythmias or inadequate pacing

137
Q

Describe the pacemaker action potential

A
138
Q

Describe the cardiac myocyte action potential

A
139
Q

What are the causes of AKI after cardiac surgery?

A

Combination of:
1. Hypoperfusion:
Hypotension
Non-pulsation flow
Reduced CO
Haemodilution
Atheroembolism
Activation of RAAS

  1. Direct nephrotoxicity:
    Ischaemia-reperfusion
    Inflammation/oxidative stress - free radicals
    Free haemoglobin
140
Q

Do you know of any criteria that can help predict hospital survival on initiation of ECMO?

A

RESP score
Respiratory ECMO Survival Prediction
Score I - V, with I having good prognosis and V having poor prognosis
Takes into account lots of things (patient characteristics, disease characteristics, state prior to ECMO)

141
Q

What is cardiogenic shock?

A

Tissue hypoperfusion due to primary cardiac failure after correction of preload

Hypotension
Trachycardia
Oliguria
+/-Organ congestion

142
Q

What is the pathophysiology of cardiogenic shock?

A

Impaired LV systolic function:
-decreased CO/SV ->decreased BP and systemic perfusion -> decreased coronary perfusion & vasoconstriction and fluid retention

Impaired LV diastolic function:
-increased LVEDP -> pulmonary congestion -> hypoxaemia

Causing ischaemia and progressive dysfunction

143
Q

What are the causes of cardiogenic shock?

A

—Ischaemia:
-Pump failure
-Valve rupture
-Conduction delay - RCA
-Arrhythmia
-VSD

Other:
-Myocarditis
-End-stage cardiomyopathy
-LVOTO
-Toxins - beta blockers & calcium channel blockers
-Contusion