Non Invasive Ventilation in critical care

Non invasive ventilation presentation about different method use in non invasive ventilation

1. Non Invasive Ventilation Dr Jean Paul Dushime

2. What is NIV? Non-invasive ventilation (NIV) is the application of respiratory support via a sealed face-mask without the use of an invasive airway device: ETT, LMA, tracheostomy

3. PHYSIOLOGY NIV can reverse many of the physiological and mechanical derangements associated with respiratory failure: A ugmentation of alveolar ventilation, helps reverse acidosis and hypercapnoea A lveolar recruitment and increased FiO2, helps reverse hypoxia R eduction in work of breathing and respiratory effort/ fatigue stabilisation of chest wall in the presence of chest trauma/surgery reduction in left ventricular afterload, improves LV function counterbalances the respiratory workload and/or reduces respiratory muscle effort, helps maintain alveolar ventilation and prevents exhaustion

4. INDICATIONS Primarily for hypercapnea A cute exacerbation of COPD D ecrease work of breathing and unload respiratory muscles post extubation acute respiratory failure Planned strategy in selected patients Obstructive sleep apnoea cystic fibrosis — e.g. bridge to transplant A cute asthma

5. INDICATIONS Primarily for hypoxaemia cardiogenic pulmonary oedema – A lveolar recruitment, decreased afterload, decreased work of breathing and R edistribution of extravascular lung water back into interstitial space P ost operative respiratory failure – in selected patients P ost-traumatic respiratory failure — rib fractures R espiratory failure in AIDS and other immunosuppressed states Pre-oxygenation prior to intubation

6. PREDICTORS OF SUCCESSFUL USE Younger age Unimpaired conscious state Moderate rather than severe hypercarbia Rapid improvement in physiological parameters

7. CONTRAINDICATIONS Cardiac / Respiratory arrest Inability to protect airway Upper airway obstruction Untreated pneumothorax Marked haemodynamic instability (e.g. shock, ventricular dysrhythmias, Upper GI bleeding) Following upper GI surgery (some debate about this) Maxillofacial surgery Base of skull fracture (risk of pneumocephalus) Staff inexperience Intractable vomiting Patient refusal

8. EVIDENCE Summary of evidence for the use of NIV: APO – studies show decreased intubation rate and faster time to resolution of respiratory failure and reduction in mortality and hospital length of stay COPD – RCTs and Cochrane review (14 RCTs) showed significant improvement in intubation rates, complications, length of hospital stay and mortality rates for NIV compared with invasive ventilation Immunocompromised – 2 studies showed benefit with NIV, i.e. fewer intubations, complications and reduced ICU and hospital mortality Asthma – probably beneficial but limited evidence

9. EVIDENCE Summary of evidence against the use of NIV: Use as rescue strategy for failed extubation – delays time to re-intubation. May be of benefit as part of weaning strategy and planned intervention post extubation especially in COPD patients ARDS – not recommended as first line therapy

10. Use of NIV Starting NIV P atient reassurance Well fitted mask with straps (nasal, full face or helmet) S et appropriate FiO2 T ime or flow cycled S tart at low pressures e.g. 10/5 cmH2O or CPAP 5 cmH20 I ncrease pressures by 2-3 cmH20 every 5 minutes until satisfactory response (up to 15-17 max) R eassess after 60 minutes plus ABG

11. Use of NIV Weaning NIV T ypical approach is trial periods off NIV during the day (e.g. 1 hour off and 2 hours) with overnight rest on NIV I f patient condition markedly improves NIV can be stopped abruptly M onitor closely for respiratory fatigue or deterioration The use of NIV for preventing post- extubation respiratory failure

12. Complications pressure ulcers/necrosis (nasal bridge) facial or ocular abrasions claustrophobia/anxiety agitation air swallowing with gastric/ abdominal distension, potentially leading to vomiting and aspiration hypotension if hypovolaemic aspiration oronasal mucosal dryness raised ICP increased intraocular pressure impaired communication impaired nutrition

13. Complications for NIV Pressure related Airflow related Pneumothorax Sinusitis Gastric inflation: vomiting/aspiration Pressure sores at the nasal bridge Dryness Nasal congestion Eye irritation

14. What materials do we need? Oxygen source Flowmeter Ventilator Interfaces : connect the face of the patient to the ventilator tubing

15. NIV way to deliver it CPAP : continuous positive airway pressure (only PEEP) BIPAP : bilevel positive airway pressure (PEEP+ PSV)

16. CPAP C ontinuous P ositive A irway P ressure Prevents alveolar collapse and open flooded alveoli The same with PEEP

17. Boussignac CPAP system

18. BIPAP (P SV and PEEP ) Gives respiratory support two levels One higher( PI ): helps ventilation One lower (PEEP) : helps oxygenation

19. BIPAP/PSV Inspiratory pressure ( PI ) : 12-15 cmH2O Expiratory pressure ( PEEP ): 4-7 cmH20 LOOK fo r : Adequate chest rise SpO2 improvement Increase in the tidal volume of the patient > 6ml/kg Diminish the respiratory rate of the patient NO more than 25 cmH2O of pressure in total! Adequate SEAL/ NO leak is important!

20. No improvement in SpO2: increase in PEEP Make sure O2 is ON : FiO2 >40% NO VT increase : increase in PI Don’t do it more than 1h if you see NO improvement!

21. Predictive of NIV failure Rapid shallow breathing index= RR/tidal volume >105, patient will most probaly need ETI Severe hypoxemia not due to pulmonary edema Low BP Poor nutritional status High WBCs

22. Mode Description Pro’s Con’s Ventilator settings / example Monitor CPAP Continuous positive airway pressure Delivers a continuous pressure (CPAP == EPAP == PEEP) throughout the respiratory cycle, holding open collapsible airways and improving oxygenation. Patient triggers all breaths. Improves oxygenation ; relatively well tolerated. Useful in obstructive apneas, reduces intubations in CHF exacerbations. Does not assist ventilation (risk of hypoventilation) EPAP, FIO2 +8, 60% Ventilation S/T Spontaneous Timed ( a.k.a BiLelel , BiPAP ) Sets, an inspiratory (IPAP) & expiratory pressure (EPAP). Every breath is supported with positive pressure. Patient triggers breaths, there is also a backup rate. (Similar to pressure support) Improves ventilation & oxygenation . Useful in COPD to avert intubation & reduce mortality . May also reduce mortality in patients with immunosuppression presenting with hypoxemic respiratory failure . Can have volutrauma Backup RR, IPAP, T i , Risetime , EPAP, FIO2 Ventilation Volumes 8 bpm, 16 cmH 2 O, 1 sec, 0.15 sec , +8, 60% T - time/pressure/flow, C – flow, L - pressure 12 bpm, 25 cmH 2 O, 0.9 sec, 0.15 sec , +8, 60% AVAPS Adaptive volume assured pressure support (a.k.a. iVAPs ) Hybrid mode that dynamically adjusts inspiratory pressure (IPAP) to deliver a desired tidal volume. (Analogous to PRVC/VC+ modes) Ensures minimum ventilation (within a desired pressure range). Not proven superior Can have volutrauma With greater patient effort (e.g. gasping) will provide less support. Backup RR, Goal TV, P min , P max , Risetime, PEEP, FIO2 Ventilation pressures & volumes T - time/pressure/flow, C – volume, L - volume 8 bpm, 450cc, 10, 20, 0.15 sec , +8, 60%

23. by Nick Mark MD non-invasive positive pressure ventilation onepagericu.com @ nickmmark Link to the most current version → ONE PURPOSE & DEFINITIONS: Scalars correspond to pressure, flow, & volume waveforms Non-invasive positive pressure ventilation (NIPPV) is a method of supporting ventilation and oxygenation . NIPPV can be used in acute respiratory failure to avoid endotracheal intubation . EPAP (expiratory pressure) = PEEP = CPAP helmet full face partial face nasal Heater circuit rate 16 VT 500 V3 8.5 PIP 22 ipap 15 epap 15 rate 12 FiO2 60 i time 1.0 rise pH / PCO2 / PaO2 / HCO3 SpO2 VENTILATION OXYGENATION To increase the pH  increase the driving pressure (IPAP – EPAP) To increase PaO2 / SpO2 adjust oxygenation parameters (FiO2 & EPAP) ABG Pulse Ox May be more comfortable for CPAP or low pressure High air-leak. May cause pressure ulcers on nose. Pt can take oral meds easily. INDICATIONS : CONTRA-INDICATIONS: Unresponsiveness/coma Inability to trigger breath Inability to protect airway / remove mask Risk of emesis / copious secretions Recent head/neck surgery COPD exacerbation (↓intubation, ↓ mortality) Cardiogenic pulmonary edema (↓ mortality) Other causes of respiratory failure DNI status Extubation to NIPPV Patients can tolerate higher pressures using masks than nasal interface. Full face masks are less likely than partial to cause pressure ulcers, & generally have less air-leak. Comfort is variable. NIPPV contra-indicated? Intubation indicated? INTUBATE Choose an appropriate interface Choose a mode to correct the underlying problem High air-leak / poor patient comfort? reassess Achieving oxygenation & ventilation goals? failure ? optimize optimize yes no LEAK 16 37 CC BY-SA 3.0 v1.1 (2021-05-30) (Not all NIPPV devices can be used with heater & humidifier) May be better tolerated , may reduce the likelihood of requiring intubation, & decrease mortality . No risk of pressure ulcers.

24. Questions?