1. Dr Chaitanya Vemuri Int.Med M.D Trainee

2.  The choice of ventilator settings – guided by clearly defined therapeutic end points.  In most of cases : primary goal is to correct abnormalities of arterial blood gas tensions  Accomplished by adjusting minute volume - to correct hypercapnea oxygen supplementation – to correct hypoxemia

3.  Choice of inspired gas composition  Means to ensure the machine’s sensing of patient’s demand  Definition of machine’s mechanical output

5.  Confirm indication for mechanical ventilation  Invasive / Non invasive  Check Connections & Circuit  Self test  Select mode  Set variables  Alarm settings  Connect to patient  Monitor and reassess

6.  Patient not breathing  Patient breathing but not enough  Patient breathing enough, but pt hypoxemic / hypercapneic  Patient breathing with normal gas exchange, but working hard  Airway protection

7.  LABORATORY CRITERIA  CLINICAL CRITERIA  OTHER CRITERIA

8.  Blood gases : PaO2 < 55 mm Hg PaCo2 > 50 mm Hg pH < 7.32  PFT : Vital Capacity < 10 ml/Kg -ve inspiratory force <25cm H20 FEV 1 < 10 mL/Kg

9.  Apnea / Hypopnea  Respiratory distress with altered mentation  Clinically apparent increasing work of breathing unrelieved by other interventions  Need for airway protection

10.  Controlled hyperventilation ( eg head injury )  Severe circulatory shock THERE IS NO ABSOLUTE CONTRAINDICATION FOR MECHANICAL VENTILATION

14.  To check : - leak - compliance - resistance of circuit - sensors  Needs to be done : - before connecting to patient - once in 2 weeks - whenever circuit is changed

15.  Depends on : Patients requirement User comfort Availability

16.  For PO2 : adjust FiO2, PEEP  For PCo2 : adjust TV, RR

18.  Tailored to need of the patient  SIMV / A/C – versatile modes for initial settings  In pts with good resp drive & mild – mod resp failure – PSV

19.  Initial TV : 5 – 8 ml/Kg of ideal bd wt  Lowest values are recommended in presence of Obstructive airway ds & ARDS  Goal : to adjust TV so that plateau pressures are less than 35 cm H20

20.  8 – 12 breaths per minute : pts not requiring hyperventilation for treatment of toxic/metabolic acidosis or intracranial injury  Initial rate may be low ( 5 – 6 breaths per min ) in asthmatic pts where permissive hypercapnic technique is used

21.  Lowest FiO2 that produces an Sp02 > 90 % PaO2 > 60 mm Hg is recommended

22.  Normal I:E ratio to start is 1:2  Reduced to 1:4 or 1:5 in presence of obstructive airway disease in order to air trapping  Inverse I:E – in ARDS

23.  60 L/min is typically used  Increased to 100 L/min : to deliver TVs quickly and allow for prolonged expiration in presence of obstructive airway ds

24.  Titrated according to PEEP and BP  High PEEP ( > 10 H20 ) – pneumonia, ards  PEEP – reduces risk of atelectasis - increase no of open alveoli ( decrease V/Q mismatch ) - in CHF : decrease venous return  Physiological PEEP ( 3-5 cm H20 ) : to prevent decrease in FRC in normal lungs

25.  Set at -1 to -2 cm H20  NEWER VENTILATORS SENSE INSPIRATORY FLOW and thereby reduce work of breathing associated with ventilator triggering

26.  Mode : Complete / Partial. VCV/PCV  Rate : titrate to Pco2  Tidal Volume : 5 – 8 ml / Kg  Flow rate & Pattern : 4 – 8 times Minute Ventilation  I:E = 1:2 to 1:4  FiO2 : titrate to O2 Saturation / Pa O2  PEEP : titrate to PaO2 & BP  Trigger : Adjust to synchronize

27.  Fixed alarms : disconnection o2 sensor  Set alarms : volume pressure rate apnea

28.  Patient  Monitor : pulse, bp, rr, spO2  Ventilator  Abg  Volume  Pressure  Rate  Patient comfort / synchrony

30.  For Paralysed pts : CMV or A/C mode  For Non paralysed pts : SIMV mode  Pts with normal resp effort mild resp failure : PSV mode

31.  Hypoxia corrected by High FiO2  Increase Expiratory Flow Time to max : to prevent increase intrinsicPEEP  RR : 6 -8 breaths / min ( permissive hypercapnia )  I : E : increased 1:2

32.  A/C mode  Tidal Volume : 6 ml/Kg  PEEP : 5  Ventilatory rate : 12 titrated to maintain Ph > 7.25

33.  Respond well to positive pressure ventilation (opens alveoli, reduces preload)  Many benefit from trial of noninvasive CPAP / BiPAP  Intubated pts usually manage to oxygenate well  But PEEP can be increased to improve oxygenation and reduce preload