respiratory failure

Question 1

what is the key sign/symptom of resp failure

Answer 1

shortness of breath - due to inadequate gas exchange

Question 2

what is resp failure

Answer 2

syndrome of inadequate gas exchange due to dysfunction of one/more components of resp system

Question 3

what components is the respiratory system broken down into

Answer 3

nervous system
respiratory muscle
pulmonary

Question 4

what parts of the nervous system are involved in resp failure

Answer 4

cns,brainstem - resp centre found in ventrolateral medulla

neuromuscular junctions

Question 5

what muscles are involved in resp failure

Answer 5

diaphragm and thoracic muscles

extra - thoracic muscles

Question 6

pulmonary components of resp failure

Answer 6

alveolar - capillary
circulation
any airway disease e.g copd,fibrosis

Question 7

what is the 3rd leading cause of death globally (2017)

Answer 7

chronic respiratory disease

Question 8

what is the biggest risk factor for chronic respiratory disease in men

Answer 8

smoking

Question 9

what is the biggest risk factor for chronic respiratory disease in women

Answer 9

household air pollution from solid fuels

Question 10

what is the criteria used to classify ards

Answer 10

berlin definition:
timing
imaging
origin of oedema
oxygenation

Question 11

what stats tell us its mild disease

Answer 11

200 mmHg 5cm h2O

Question 12

what stats tell us its moderate disease

Answer 12

100mmHg 5cm H2O

Question 13

what stats tell us severe disease

Answer 13

PaO2/FiO2 <100 mmHg with PEEP >5cm H2O

Question 14

how can we classify acute respiratory failure/disease

Answer 14

pulmonary - infection,aspiration, primary graft dysfunction
extrapulmonary - trauma, pancreatitis,sepsis
neuro muscular - myasthenia/gbs

Question 15

how can we classify chronic resp disease

Answer 15

pulmonary/airways:
copd, lung fibrosis,cf,lobectomy
musculoskeletal: muscular dystrophy

Question 16

how can we classify acute on chronic resp disease

Answer 16

infective exacerbation of: copd/fibrosis
myasthenic crises
post operative

Question 17

what is type 1 resp failure

Answer 17

hypoxemic - failure of oxygen exchange

pao2<60

Question 18

what are some causes of type 1 failure

Answer 18

collapse
aspiration
pulmonary oedema
fibrosis
pulmonary embolism
pulmonary hypertension
= causes alveolar flooding

Question 19

what is the response to supplemental oxygen in type 1 failure

Answer 19

refractory (stubborn/unmanageable)

Question 20

what is type 2 resp failure

Answer 20

hypercapnic - failure to exchange/remove co2

paco2 >45

Question 21

what causes hypercapnea

Answer 21

decreased alveolar minute ventilation
dead space ventilation due to
nervous system
neuromuscular
muscle failure
airway obstruction
chest wall deformity

Question 22

what is type 3 respiratory failure

Answer 22

perioperative respiratory failure
increased atelactasis (collapse of airway) due to low functional residual capacity with abnormal wall mechanics
hypoxemia/hypercapnoea

Question 23

how can we prevent type 3 resp failure

Answer 23

anaesthetics, operative technique
posture
incentive spirometry 
analgesia
attempts to lower intra abdominal pressure

Question 24

what is type 4 resp failure

Answer 24

patients who are intubated and ventilated during shock (septic,cardiogenic,neurologic)

Question 25

what are some risk factors for chronic resp failure

Answer 25

``` copd pollution recurrent oneumonia cystic fibrosis pulmonary fibrosis neuromuscular disease ```

Question 26

what are some risk factors for acute resp failure

Answer 26

``` infection - viral,bacterial aspiration trauma pancreatitis transfusion ```

Question 27

whats the first thing to look at in patients with acute resp failure

Answer 27

origin of shortness of breath

Question 28

causes of acute resp failure

Answer 28

``` lower resp infection aspiration trauma pulmonary vascular disease extra pulmonary - pancreatitis, new meds ```

Question 29

what causes acute lung injury

Answer 29

damage to interstitum causes: alveolar macrophages release cytokines: il6,il8, tnf alpha and type1 and 2 cells in response to inflammation- = alveolar fluid build up, protein rich oedema leads to degradation of surfactant migration of leukocytes e.g neutrophils into interstitium causes more oedema therefore greater distance between alveolar and blood supply

Question 30

what damps are released during lung injury

Answer 30

hmgb1 | rage

Question 31

therapies that have been tried for resp failure

Answer 31

``` steroids salbutamol surfactant n acetylcysteine neutrophil esterase inhibitor gm-csf statins ```

Question 32

what is proning

Answer 32

rolling patient onto tummy

Question 33

useful indicators to look at for ards

Answer 33

platelet count bilirubin creatinine crp

Question 34

how can we treat underlying disease in resp failure

Answer 34

inhaled therapies - bronchodilators, pulmonary vasodilators steroids antibiotics antivirals drugs - pyridostigmine, plasma exchange, iViG, Rituximab

Question 35

what type of respiratory support can be provided

Answer 35

``` physiotherapy oxygen nebulisers high flow oxygen non invasive ventilation mechanical ventilation extra corporeal support ```

Question 36

what are some multi organ support that can be given

Answer 36

cardiovascular support - fluids, vasopressors,ionotropes,pulmonary vasodilators renal support - haemofiltration haemodialysis immune therapies - plasma exchange ,convalescence

Question 37

what takes place during ards

Answer 37

``` poor gas exchange - inadequate oxygenation poor perfusion hypercapnoea infection - sepsis inflammation systemic effects ```

Question 38

ards specific intervention

Answer 38

resp support intubation and ventilation procedures to support ventilation

Question 39

what are the types of ventilation

Answer 39

volume controlled pressure controlled assisted breathing modes advanced ventilatory modes

Question 40

what are some imaging techniques we can use for management of ards

Answer 40

lung us - to evaluate how well expanded lung is/ any fluid | lung ct

Question 41

which guidelines used for escalation of therapy

Answer 41

``` use murray score pao2/flO2 on 100% oxygen cxr peep compliance ```

Question 42

what does murray scores mean

Answer 42

0 = normal 1-2.5 - mild 2.5 - severe 3 - ecmo

Question 43

inclusion criteria for ecmo treatment

Answer 43

severe resp failure non cardia cause pos pressure ventilation is not appropriate

Question 44

exclusion criteria for ecmo

Answer 44

contraindication to continuation if treatment significant co morbidity significant life limiting co morbidity

Question 45

what is ecmo

Answer 45

very invasive large cannula passed through femoral vein into ivc removal of co2 and input of oxygenated blood

Question 46

issues with ecmo

Answer 46

``` time to access referral system - geographical inequity invasive costly clotting/bleeding ```