Basic ventilatory parameters

This ppt is about how to set basic ventilatory parameters. Tidal volume, RR, Peak flow, IE ratio etc... Must learn for a working in ICU

1. Basic V entilatory P arameters Dr. Ankit Gajjar

2. Primary goal Achieve a desired minute ventilation that matches the patient's metabolic needs Adequate gas exchange Minimal lung injury

3. Basic parameters Tidal volume Respiratory rate Minute ventilation Lung Pressures Peak Pressure Platue pressure Flow / Inspiratory time / I:E ratio Flow pattern Trigger FiO2 PEEP

4. Tidal Volume Amount of air delivered with each breath 8 ml/kg (IBW) ARDS – 6 ml/kg PC variable VC fixed Avoid very high tidal volumes to prevent volume trauma

5. Respiratory Rate Neuro , post operative patients – 14-18 ARDS – 28-34 OAD – 12-14 prevention of air trapping Septic, Acidotic patients – 28-34 Monitor pH PCO 2 Air trapping

6. Minute ventilation Monitor Normal – 6-8 LPM Achieve desired pH PO 2

7. Pressures PC – Set driving pressure Pi To achieve desired tidal volume VC – monitor Ppeak , Pplatue Ppeak – peak inspiratory pressure Function of resistance and compliance Pplatue – inspiratory pressure during inspiratory hold Function of lung comliance Target <30 cm H2O Important in prevention of Barotrauma

8. Peak flow M aximum flow delivered by the ventilator during inspiration Normal Peak flow rate - 60 L per minute Higher rates are frequently necessary Acidotic patient OAD Insufficient peak flow rate is Dyspnea Spuriously low peak inspiratory pressures, and scalloping

9. Flow pattern Can be chosen in VCV In PCV always ramp wave square wave (constant flow) ramp wave (decelerating flow) The ramp wave is preferred distribute ventilation more evenly particularly in OAD decreases peak airway pressure, physiologic dead space, and PaCO2

10. Inspiratory time / I:E ratio Normal – 1:2 ARDS – 1:1/ 1:1.5 OAD – 1:3-1:5 or even prolonged Look for adequate expiratory time on flow time scaler Inadequate expiratory time causes air trapping

11. Trigger P ressure trigger Drop of pressure in airway due to patient effort Flow trigger Returned flow is less then delivered flow More sensitive decreases WOB Keep 1-3 More sensitive – auto trigger Less sensitive – increased WOB

12. FiO2 The lowest possible FiO2 to meet oxygenation goals should be used To decrease the likelihood that adverse consequences of supplemental oxygen absorption atelectasis accentuation of hypercapnia airway injury parenchymal injury Most patients - >88% >95% ACS CVA Post cardiac arrest pregnant

13. PEEP Avoid end expiratory alveolar collapse Usual – 5 Lesser OAD??? BPF Higher ARDS

14. VCV for 60 kg male Condition Airway protection ARDS OAD Septic Acidotic VTE 420-480 240-360 400-450 450-500 RR 16-18 28-34 12-14 28-34 I:E 1:2 1:1-1:2 1:3-1:6 1:2 Flow pattern decelerating Decelerating Decelerating decelerating Trigger Flow 3 Flow 3 Flow 3 Flow 3 FiO2 30 30-100 30 30 PEEP 5 5-20 0-5 5

15. Monitor Pplat MV SPO2 PCO2 pH

16. THANK YOU