Respiratory Flashcards

1
Q

Indications for Mechanical Ventilation

A
  1. Airway Support - threatened airway, impaired airway reflexes
  2. Respiratory Support - high FiO2 required
  3. Ventilatory Support - deep sedation, regulate CO2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Delivery of non-invasive ventilation

A
  1. High flow nasal O2 - humidified O2, 40-60L/min FiO2 up to 1.0.
  2. CPAP
  3. BiPAP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Advantages of HFNO

A
  1. Humidification - prevent epithelial injury, help secretions
  2. PEEP
  3. Greater FiO2 - less entrainment of atmospheric gas
  4. Reduced CO2 dead space - washout
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

CPAP

A
  • Continuous application of positive pressure throughout respiratory cycle
  • Nasal, facemask, hood
  • Better recruitment, improved V/Q
  • Cheap, well tolerated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

BiPAP

A
  • Ventilatory support by difference between IPAP and EPAP
  • Facmask
  • ECOPD, prevent post-extubation respiratory failure.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

PEEP

A

Pressure present in airway above atmospheric pressure at end expiration
Recruitment of alveoli and prevention of collapse (therefore reduced WOB)
Other physiological effects
- Improved pulmonary compliance
- Reduced venous return and preload
- Increased afterload and PVR
- Increased ICP by reduced venous drainage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Characteristics of ventilator modes

A
  • Control - pressure or volume
  • Cyclying - flow, time, pressure
  • Trigger - patient, machine
  • breath type - mandatory or spontaneous
  • breath sequence - mandatory, intermittent mandatory, spontaneous
  • synchronisation - synchronised, independent
  • guarantee - TV, MV, pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

PCV

A
  • Pinsp, PEEP, Ti
  • VT depends on compliance
  • pressure rapidly delivered and held constant - square wave pattern
  • flow decelerates
  • pressure rapidly released in expiration
  • gas equilibrates between varying alveolar time constants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

VCV

A
  • VT, PEEP, RR, flow pattern set
  • constant inspiratory flow - gradual rise in Pinsp
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pressure support

A

Pinsp, PEEP, expiratory flow trigger set

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Ventilator cycling

A
  • Time - mandatory modes, insp and exp determined by time
  • flow - insp and exp commenced after sensing change in flow (patient attempts breaths)
  • pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Special modes

A

ASV - adjusts support based on patient requirements. support delivered in response to RR and effort
NAVA - neural assist - electronic activity from diaphragm, monitored via specialist NG tube
SIMV - time cycled mode mandatory breaths may be machine or patient triggered. pressure or volume controlled. spont ventilation permitted at varying parts of the cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

APRV - Airway Pressure Release Ventilation

A

Advanced ventilatory mode
Maximises alveolar recruitment - used when alveolar recruitment felt to be possible
P-high, Thigh, Plow (0) and Tlow
CO2 release at Plow
breath spontaneously
extreme inverse ratio
Ads - recruitment, lung homogeneity, reducing in cyclical opening and closing of alveoli
disads - high local pressure, tachypnoea, rv dysfunction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Indications for proning

A

Critical care
- mod-severe ARDS Pf < 150 (< 48hrs into disease after IPPV optimised) PROSEVA trial
Theatre
- surgical access e.g. spine, posterior fossa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Contraindications

A

Absolute
- open chest, <24h post cardiac surgery, central ECMO cannulas, unstable spine
relative
- severe CVS instability, pregnancy, recent tracheostomy, significant trauma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Risks of proning

A

Instability
- airway dispalcement
- line displacement
- increased into abdominal pressure
- reflux and aspiration
Patient injury
- pressure sores
- brachial plexus
- periorbital oedema, chemises, blindness
Staff injury

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How to prone

A

Pre-procedure
- MDT decision
- check with nurse in charge senior doctor re. timing
- ensure any procedures that require supine position carried out
- system assessment e.g. airway position, suction. 100% O2. stop non-essential infusions
- eye / nipple protection, remove anterior ecg stickers
- spigot and aspiration NG tube
Procedure
- minimum 1 airway and 2 each side
- pillows to chest, iliac crests, knees
- sheet over top and roll edges (Cornish pasty)
- slide away from ventilator
- turn to 90 degrees
- complete prone
post-procedure
- re-assess A-E
- check pressure areas
- complete positioning e.g. swimmers, revers trendelenburg
- 2-4 hourly head turn and arm change
- document

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

conscious proning

A

covid. if fio2 > 28% or more than basic resp support
position change every 1-2 hrs - fully prone, right recumbent, sitting up 30-60 degrees, left recumbent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Types of extra-corporeal life support

A
  • VV-ECMO
  • VA-ECMO
  • AV-ECMO (rare)
  • ECCO2R
  • Cardiopulmonary bypass
  • VAD
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

VV-ECMO concept

A

Gas exchange in native circulation failed
an oxygenator incorporated into extra-corporeal circuit
oxygenation determined by circuit flow rate and post-oxygenator oxygen content. increased by increasing flow rate
co2 diffuses out through oxygenator determined by sweep gas flow rate. CO2 more soluble, diffuses more readily and maintains diffusion gradient. clearance therefore related to sweep gas rather than blood flow
conventional ventilation reduced to rest settings and allow healing of pathology
VV oxygenator flows limited to 5-6l/min (cannula size)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

VV-ECMO indications

A

despite optimum conventional management: including trial of proning:
- hypoxaemic resp failure PF < 80
- hypercapnia resp failure pH < 7.25
“potentially reversible severe resp failure”
- ventilatory support as bridge to lung transplant
specific clinical conditions include
- severe ARDS
- BPF
- severe asthma
- thoracic trauma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

VV-ECMO contraindications

A

Absolute
- anticipated non-recovery without a viable plan to decannulate
relative
CNS - haemorrhage, severe debilitating pathology, significant njury
refractory or established MOF
Haem - bleeding, inability to anticoagulant
IPPV > 7 days with plat pressure > 30 and fio2 > 90
older age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

O2 delivery in VV ECMO

A

O2 content minimum 240ml.min
O2 delivery minimum 300ml.min
Arterial O2 is mixture of venous blood removed and passed through oxygenator and blood passing through lungs and is typically 80-90%

increasing circuit flow increased circuit:native and therefore total O2 content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Issues on VV ECMO

A

recirculation - post oxygenator blood returning to oxygenator and not systemic circulation (high venous saturations) more common with single lumen dual cannula access
hypoxaemia - increased VO2 e.g. sepsis, recircualtion. DO2 / VO2 5:1 increase flow
CO2 removal - sweep gas 1-9l/min in 100% O2
Chatter - partial venous cannula occlusion e.g. rhythmic ventilation, cough, valsava
suck down - intravascular volume restriction or cannula misplacement abrupt reducing flow to 1l/min with full pump speed - haemolysis, air embolism
high Paco2 - may be increased metabolic state, circuit problem, monitoring problem. can increase sweep gas flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

ECMO emergencies

A

gas embolism - clamp return line, clamp drainage line, switch off pump, remove air using syringe at oxygenator port
accidental decannulation - turn off pump, compress site, major haemorrhage, emergency recannulation
circuit failure - change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

VV-ECMO cannulas

A

Single lumen dual cannula - IJ - fem
bicaval dual lumen single cannula - RA / IVC
bifemoral

Dual lumen single cannula improved mobility, needs fluoroscopy / echo guidance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Haemodynamics on VV ecmo

A

hypoxia, hypercarbia, acidosis lead to elevated PA pressures, rv dysfunction. implication
- vv ECMO no direct haemodynamic support - need to manage conventionally
- improved oxygenation and co2 clearance improves PA pressures, rv function, lv function
- reduced thoracic pressures due to lower IPPV settings may also improve haemodynamics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Rest ventilator settings

A

recommended PEEP 10 Pinsp 25 rate 10 FiO2 as low as possible e.g. 30%
CESAR / EOLIA settings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

weaning ecmo

A

reduced circuit flow or reduce sweep gas FiO2 from 1.0 - 0.21
over hours - days
assess ventilatory reserve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

ECMO scoring systems

A

RESP - predicted survival on ecmo
Murray - predicted mortality without ecmo
RESP -22 to 16. Class I > 6 92% in-hospital survival. class V < -6 18% survival
Murray
- consolidation (quadrants on CXR)
- compliance
- P/F ratio
- PEEP
Severe > 2.5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

ECMO trials

A

CESAR
- improved outcomes from severe potentially reversible resp failure in those transferred to ecmo centre (not with use of ecmo) vs conventional
- advocates transfer to specialist centre - Murray Score > 3 pH < 7.25 on optimum mx
EOLIA
- severe ARDS
- VV-ECMO vs VCV (28% crossover)
- no difference in 60d mortality.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is ventilator weaning?

A
  • slowly reducing ventilator support over time, increasing patients own ventilatory drive and extubation
  • may be minutes - months
    Simple: liberation from ventilator on first attempt (70%)
    Difficult - 2-7 days after initial assessment
    Prolonged - > 7 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Clinical assessment of readiness to wean

A
  • Initial pathology resolved
  • Patient condition optimised
    A: cough / reflexes satisfactory, secretions manageable, cuff leak present
    B: FiO2 < 40%, spont breathing, adequate strength, min PEEP
    C: stable
    D: obeying commands
34
Q

Objective assessment of weaning

A
  • RR < 30
  • TV > 5ml/kg
  • FVC > 15ml/kg
  • MV < 15l/min
    Max inspiratory pressure < 30cmH20 (resp muscle strength)
    Rapid shallow breathing index = f/Vt (L) - some evidence for extubation with RSBI < 105 spring SBT
    P0.1/PImax > 0.3 = negative airway pressure from first 0.1s of occluded inspiration
35
Q

Describe spontaneous breathing trial

A
  • screen for readiness to wean
  • sedation hold
  • 30 min trial of T piece or minimal CPAP +/- PS
  • assessment of success or failure
  • if well tolerated consider extubation

Criteria for failure
B: RR > 35, SpO2 < 90%, high WOB
C: HR > 140 or change > 20%, SBP > 180 or < 90
D: agitation

36
Q

Problems with weaning difficulty

A

increased LOS, VAP, ICU-AW, mortality
extubation failure and issues

37
Q

Causes of failure to wean

A

Resp
- secretions
- poor cough
- inappropriate ventilator settings
- resistance from ETT
- VAP / unresolved infection
- Pulmonary oedema
CVS - High myocardial workload
- metabolic demand
- unresolved CVS failure
- fluid overload
- anaemia
CNS
- delirium
- weakness
- pain
Other pathology e.g. burns, malnutrition

38
Q

Indications / advantages for tracheostomy

A

Indications
- prolonged wean
- longterm / home ventilation
- airway toilet
- upper airway obstruction e.g. laryngeal, VC
Advantages
- patient comfort
- reduce sedation
- improved mouth care
- reduced airway oedema
- ability to phonate / VC mobilisation
- improved larnyngeal sensation / swallowing

39
Q

Tracheostomy timing

A

multifactorial
TRACMAN study early < 4d late > 10 days no difference in high risk prolonged ventilation

40
Q

Percutaneous tracheostomy insertion

A

Pre-procedure
- CI e.g. coagulopathy, high FiO2
- consent, MDT decision, NIC
- team allocation - airway / bronch, sedation e.g. nurse, procedurist
- equipment prep
- positioning, USS
- 100% O2, aspirate NG
Procedure
- asepsis, clean skin
- xylocaine / adrenaline
- airway person retracts ETT until cuff seen at cords
- needle, with cannula, syringe, saline 1/2 or 2/3 tracheal rings
- midline insertion aspiration until air
- thread cannula, remove needle
- check cannula with bronc
- pass guide wire
- check with bronchiole
- scalpel incision then serial dilators
- rhino dilator and leave in situ for a minute or two
- remove and pass tracheostomy
- inflate cuff, ensure ETCO2, remove oral tube
- 2 x sutures and secure in place with tie
post-procedure
- CXR
- wean sedation
- document

41
Q

Complications of tracheostomy

A

immediate
- bleeding / haemorrhage
- failure
- pneumothorax / submit emphysema
- aspiration
- damage to local structures e.g. thyroid, RLN
- loss of airway
short term
- deterioration in ventilation
- infection
- obstruction
- displacement
- tracheostomy’s-innominate artery fistula
long term
- granuloma
- VC dysfunction
- dysphagia, dysphonia
- stenosis

42
Q

When can a patient be decannulated?

A
  • improving trajectory
  • MDT opinion, nursing, physio
  • tolerating cuff deflation for prolonged period of time e.g. 24hrs
  • secretion burden manageable
  • minimal O2 requirement
43
Q

Causes of restrictive lung diease

A

Pulmonary
- ILD
- ARDS
- TB
- Lobectomy
Extrapulmonary
- Resp centre = drugs, trauma
- Neurological - polio, GBS
- Neuromuscular = MG
- Muscular = dystrophies
- Thoracic wall = obesity, kyphoscoliosis, rib fracture
- pleural = plaques, effusions, PTX

44
Q

Types of interstitial lung disease

A

300 + conditions
Known aetiology
- Iatrogenic e.g. radiation
- Extrinsic allergic alveolitis (hypersensitivity pneumonitis) e.g. farmers lung, pigeons lung
- pneumonconiosis (lung injury from dust particles) asbestosis, silicosis
- post-infectious
Unknown aetiology
- Idiopathic intersistial pneumonias
- sarcoidosis
- connective tissue disease
- lymphangioleiomyomatosis (LAM)

45
Q

Classification of idiopathic interstitial pneumonias (ERS)

A

Major
- acute interstitial pneumonia (AIP)
- idiopathic pulmonary fibrosis (IPF) - worst mortality
- idiopathic non-specific interstitial pneumonia (NSIP)
- cryptogenic organising pneumonia (COP)
- respiratory bronchiolotisi ILD (RB-ILD)
Rare
- idiopathic lymphoid intersistial pneumonia
Unclassifiable

46
Q

Acute interstitial pneumonia

A

progressive hypoxaemia
high mortality with no treatment
survivors have good outcomes
some might have recurrence or chronic disease

47
Q

Sarcoidosis

A

systemic inflammatory condition commonly affecting lungs caused by collections of inflammatory cells forming granulomas.
can affect skin, CNS, liver, heart
CXR grading 1-4 - BL hilar lymphadenopathy, with infiltrate, infiltrates only, fibrosis
steroids, other immunosuppressants

48
Q

Non-ICU management of ILD

A
  • anti-inflammatory drugs
  • anti-pulmonary hypertensives e.g. PDE-5 inhibitors
  • Antifibrotic therapies e.g. nintedanib
    Advanced - ILD
  • LTOT (symptomatic relief)
  • Rehabilitation
  • lung transplant
  • palliative care
49
Q

ILD referrals to critical care

A

Diagnosis crucial
Most commonly AIP, acute exacerbation of IPF, fulminant COP
Considerations
- aetiology / reversibility / response to treatment
- usual therapy e.g. LTOT
- complications - pulmHTN, cor pulmonale
- functional status
- Ix - PFTs, echo, BAL
- specialist opinion
Resp support - I+V usually inappropriate in IPF. NIV MDT decision
Steroid - pulsed MP - rapid progressive ILD with respiratory failure
cyclophosphamide

50
Q

Sleep disordered breathing

A

several conditions causing hypoventilation during sleep
- snoring - partial airway obstruction without sleep disturbance
- OSA - intermittent complete airway obstruction
- OSA syndrome - OSA with daytime symptoms
- obesity hypoventilation syndrome - breathing reduced throughout sleep with or without airway obstruction. hypercapnia during day. (BMI > 30, PaCO2 > 6.5, SDB)

51
Q

OSAS

A

daytime symptoms - headache, somnolescence, cognitive impairment
associated hypertension, cardiovascular dysfunction
contributory factors - male, smokers, obesity, reduced nasal patency
overnight polysomnography - AHI
- Mild < 5-15 / hr
- Mod 15-30
- severe > 30
Management
- conservative - lifestyle, weight loss
- CPAP
- mandibular re-positioning
- surgery - tonsillectomy, bariatric

52
Q

Tuberculosis

A

Infectious disease caused by mycobacterium tuberculosis causing respiratory and/or multisystem disease
symptoms
- cough
- haemoptysis
- fever, weight loss, night sweats

53
Q

Critical care and TB

A
  • respiratory failure - often associated pneumonia, COPD or malignancy. significant comorbidity e.g. HIV
  • Miliary TB - haematological dissemination - MODS, associated with immunosuppression
    CNS TB - meningitis, tuberculomas.
    other indications
  • TB related - pericardial effusion, massive haemoptysis, DIC (ciliary)
  • treatment related - renal / liver failure
    Challenges
  • difficult sampling
    infectivity
  • multidrug resistance
54
Q

TB diagnosis

A
  • sputum acid fast bacilli (or PCR)
  • bronchoscopy AFB (or PCR)
  • alternative sites - LNs, CSF, pleural effusions
  • overal clinical picture inc radiology
    Culture
  • 2 x sputum for MC/S
  • 2-4 weeks
  • initial ZN stainig useful
  • bronchoscopy high sensitivity
    Radiology
  • upper lobe nodules, cavities, lymphadenopathy
55
Q

critical care management

A
  • MDT (resp, micro, ID, neuro)
  • infection control - negative pressure, PPE
  • Anti-TB drugs - 6-19mo
  • co-infection - HIV, pneumonias
  • complications - steroids for meningitis, hyponatraeumia, hydrocephalus, immun reconstitution
56
Q

ARDS definition

A

Acute inflammatory lung disease causing respiratory failure manifested by hypoxaemia, consolidation, reduced compliance

57
Q

Berlin definition

A
  1. Hypoxaemia P/F < 39.9kPA
  2. Bilateral infiltrates (CT / CXR)
  3. Within 1 week of trigger
  4. Not explained by cariogenic pulmonary oedema

Mild P/F 26.6 - 39.9 Kpa
Moderate P/f 13.3 - 26.6 Kpa
Severe P/f < 13.3 kPa

58
Q

Pathophysiology of ARDS

A
  • Epithelial and endothelial injury within alveolus
  • inflammation of alveolar membrane - increased permeability, protein rich pulmonary oedema
  • endothelial dysfunction and leakage of fluid and inflammatory cells into alveolus
  • inactivation of surfactant
  • consolidation, collapse, loss of gas exchange surface area
  • loss of pulmonary vascular tone and hypoxic pulmonary vasoconstriction
  • loss of gas exchange
59
Q

histological phases of ARDS

A
  1. Exudative - 1st week - protein rich fluid flooding alveoli
  2. Proliferative - fibroproliferation and micro thrombi
  3. Fibrotic - widespread remodelling and scarring
60
Q

Causes of ARDS

A

Pulmonary
- infection - bacterial, viral, fungal
- aspiration
- contusion
- Inhalational injury
- drowning
Extra-pulmonary
- Sepsis
- Major trauma
- Pancreatitis
- Burns

61
Q

ARDS treatment

A

underlying cause and best supportive care
Mild - LPV, conservative fluid balance
Moderate - prone, NMB, higher PEEP
Severe - VV-ECMO if Murray score > 3 or pH < 7.2
general - nutrition, VTE prophylaxis, glycemic control

62
Q

Steroids in ARDS

A

Equipoise
DEXA-ARDS - mortality benefit and ventilator free days. no proning.
recovery in covid-ards benefits

63
Q

Hyperoxia

A

supernormal arterial partial pressure of O2
degree, duration and patient determine consequences. sometimes beneficial, sometimes harmful

64
Q

harmful O2 therapy

A

patients at risk of hypercapnic respiratory failure
- COPD
- Bronchiectasis
- Neuromuscular disease
- Morbid obestiy

65
Q

Hyperoxia recommended against in critical illness

A
  • Acute MI
  • Acute stroke
  • Post ROSC

Others
- Neonatal - retinopathy, bronchopulmonary dysplasia
- bleomycin
- oxygen toxicity

Plus
- wastage
- energy consumpation
- fire risk
- cost

66
Q

Pathophysiology of oxygen toxicity

A
  • ROS generated by ETC
  • increased imbalance between ROS and antioxidants due to hyperopia
  • increased exposure of tissues to toxic interactions
  • ROS cause harm by damaging DNA.RNA, damaging cell membrane, oxidant enzymes and impairing protein function
  • Exposure time and PIO2 contribute
67
Q

Effects of O2 toxicitt

A

Pulmonary
- epithelial damage
- chest pain, reduced VC
- inflammation
- stages similar to ARDSm permanent fibrosis possible
others
- impaired HPVC
- reduced CO2 elimination
- altered control of breathing
- absorption atelectasis
CNS
- nausea headache, dizziness, irritability seizures in hyperbaric conditions

68
Q

Beneficial effects of high O2

A

Normobaric
- CO elimination
- PTX resorption
- cluster headache
- induction of anaesthesia
Hyperbaric
- decompression sickness
- wound healing

69
Q

Oxygen target trials

A

ICU - ROX - 90-97% vs conventional. primary and secondary outcomes no difference
HOT ICU - 8 vs 12 kPA - no difference
UK ROX 88-92 vs conventional - ongoing

70
Q

HAP

A

pulmonary infection contracted after 48 hr of admission to hospital

71
Q

VAP

A

pulmonary infection contracted after 48 hr of mechanical ventilation
significance
- increase LOS, ventilator days, mortality

DDX
- HAP/CAP
- ARDS
- Pulmonary oedema
- contusion
- PE

72
Q

VAP diagnosis

A

difficult - clinical, micro, radiological features
CPIS > 6 (MAX 12)
- increase pulmonary secretions
- fever
- leucocytosis
- P/F ratio
- new infiltrates
- +ve tracheal aspirate

73
Q

VAP pathophysiology

A

Biofilm / aspiration
- ETT disrupts normal host defence
- secretions pool above cuff - colonised oropharyngeal
- slowly migrate through folds in cuff to trachea
- biofilm formation in tube - pushed in by ventilator

74
Q

care bundle

A

group of evidence based interventions which together significantly improve outcomes

75
Q

VAP prevention

A

care bundle
- head up 30 degrees
- daily sedation holds (reduce duration of intubation)
- mouth care
- subglottic suction
- tracheal tube pressure monitoring
- appropriate PPI (avoid unnecessary - bacterial overgrowth)

high impact intervention - reduce VAP, MRSA, ABX

other methods
- hygiene during handling airway euquipment
- tracheal tube design - cuff shape
- SDD

76
Q

PE Risk factors

A

Strong
- lower limb fracture
- hospitalisation for HF or AF
- hip or knee replacement
- major trauma
- MI
- previous VTE
- spinal cord injury
Moderate
- AI disease
- CCF
- OCP
- post-partum
- cancer
-thrombophilia
weak
- 3 d bed rest
- immobility due to sitting
- obestity
- pregnancy

77
Q

PE spiral of death

A
  • increased RV afterload
  • RV dilaation
  • increased wall tension and RV O2 demand
  • RV ischaemia,
  • reduced RV contactility / output
  • reduced LV preload / CO / systemic BP
  • reduced coronary perfusion / RV O2 delivery
  • obstructive shock
78
Q

PE risk strtificiation

A

High risk
- cardiac arrest
- shock - sBP < 90 and end organ hypoperfusion ( GCS, oliguria, cold skin, lactate)
- persistent hypotension < 90 for 15 mins
- reperfusion tx, haemodynamic support
Intermediate high risk
- PESI III-V / RV dysfunction (TTE/CTPA) / elevated trop
- monitoring, rescue reperfusion
Intermediate low
- PESI III-V / RV dysfunction or troponin
- hospital mx
Low risk
- none or above
- early outpatient mx

79
Q

PE Echo

A

Basal RV:LV ratio > 1
Mcconnells sign (RV free wall akinesia with sparing of the apex)
flattened septum
distended IVC
TAPSE < 16

80
Q

mx acute RV failure in high risk PE

A
  • volume optimisation - cautious 500ml bolus (normal / low CVP)
  • NA 0.2-1mcg/kg/min - increases RV inotropy and systemic BP, restore CoPP beware excess vasoconstriction
  • dobutamine 2-20mcg/kg/min - RV inotropy, may worsen arterial hypotension
  • MCS- VA-ECMO
81
Q

throbmolysis PE

A
  • faster improvement in PAP, PVR vs LMWH / UFH
  • greatest benefit in those within 48h symptom onset
  • sig reduction in combined mortality and recurrence with 9.9% rate of severe bleeding, 1.7% rate of ICH
  • PEITHO trial intermeidiate PE - reduced haemodynamic compriomise, worse major bleeding and stroke, no reduction in 30 d mortality
    ABSOLUTE CI
  • active bleeding
  • CNS malignancy
  • haemorrhagic or ischaemic stroke last 6mo
  • 3/52 - major trauma, surgery
    relative CI
  • TIA
  • anticoagulation
  • advanced liver disease
82
Q

PE scoring systems

A

PERC
wells score - low risk - d-dimer. high risk - ctpa
PESI (PE Severity index)