Mechanical Ventilation in Special Conditions

1. Mechanical Ventilation in Special Conditions

2. Mechanical Ventilation: Outline Head injury Chest Trauma Bronchopleural Fistula

3. Traumatic Brain Injury

4. Prevalence of extracerebral organ dysfunction in TBI

5. Cerebral Compliance Curve CPP= MAP-ICP Intracranial pressure CPP Intracranial volume

6. Cerebral Compliance Curve PaCO2 CPP PaO2 Cerebral Blood Flow 50 100 150

7. Head Injury: MV Monitoring Peak alveolar pressure, airway pressure, auto-PEEP PaCo2 end tidal PCO2 Intracranial pressure Jugular venous oxygen saturation Pulse oximetry Heart rate and systemic blood pressure

8. Hyperventilation in Traumatic Brain Injury Causes cerebral vasoconstriction Decreases cerebral blood flow Decreases cerebral blood volume Increases ICP Has been proven to be of benefit in head injuries

9. Head Trauma • Cerebral physiology • ICP • CBF • Cerebral oxygenation : SJO2, PbrO2 • Hyperventilation • Lung protective strategy • PEEP • Extubation

10. Hyperventilation in TBI Chronic hyperventilation (PCO2 < 25) should be avoided Prophylactic hyperventilation (PCO2 < 35) in the first 24 h should be avoided May be necessary for a brief period with acute neurologic deterioration

11. Head Trauma + • Lung protective strategy • Hypoventilation  PCO2   ICP  • No evidence of detrimental effect • Use protective ventilation • Observe ICP and CPP if PCO2▲ • PEEP • ICP  • MAP  • Depends on compliance • Extubation • LOC • Cough • Tracheal secretions

12. Head Trauma + • Lung protective strategy • Hypoventilation  PCO2  ICP  • No evidence of detrimental effect • Use protective ventilation • Observe ICP and CPP if PCO2▲ • PEEP • ICP  • MAP  • Depends on compliance

13. Head Trauma • Extubation • LOC • Cough • Tracheal secretions

14. Hyperventilation & CBF

15. Head TraumaCBF and ICP with hyperventilation ►CBF◄ ▼ICP

16. Head Trauma • Extubation • LOC • Cough • Tracheal secretions

17. Decompressive Craniotomy • CSF Drainage • HOB > 30 degree • Head in neutral position • Vetriculostomy ICP =30 • Decrease Brain Water • Mannitol • Avoid D5% • Diuretics • Decrease Oxygen Demand • Prevent seizure • Sedation • Treat pain • Barbiturate coma • Avoid hyperthermia • ? hypothermia ICP= 10 Vasoconstriction Pa co2 25-30 CPP = MAP – ICP • Avoid ↑ Intrathoracic Pressure • Suppress Valsalva maneuvers • Suppress cough • ↓ Mean airway pressure • Minimize use of PEEP • Treat distended abdomen • Maintain adequate MAP • Adequate CO • Use inotropic Agents • Adequate filling pressures • Avoid hypotensive agents • Treat infection abruptly Intrathoracic Pressure (-3 cm H2O) Venous Return MAP (90)= CO X SVR

18. CMV (A/C), PCV or VC, VT 4-8 mL/kg, FiO2 1, rate 20/min TI1s, PEEP 5 cm H2O CMV (A/C), PCV or VC, VT 4-8 mL/kg, FiO2 1, rate 15/min TI1s, PEEP 5 cm H2O yes no Titrate FiO2 for SpO2 ≥ 92% Pplat > 30 PCO2 no ↑ rate ↓ rate <35 >45 yes 35-45 ↓ VT no FiO2 > 0.6 <70 PaO2 >100 ↓ FiO2 70-100 yes FiO2 > 0.6 ICP < 20 no yes ↑ FiO2 More aggressive Medical therapy yes no >20 ↑ PEEP ICP ICP <20 Maintain Ventilator Setting <20 Slowly ↓ rate to initial setting Underlying lung disease >20 ↑ rate

19. Chest traumaWho Gets Admitted? Sternal fractures mediastinal injury Any 1th, 2nd, 3rd Rib fractures > 1 Rib fracture in any region Pulmonary contusion Subcutaneous emphysema Traumatic asphyxia Flail segment Arrhythmia or myocardial injury

20. Flail Chest

21. Flail chest

22. Flail Chest

24. BPF

25. BPF

26. BPF

27. Adverse effects of BPF in the ventilated patient

28. Guidelines for ventilator management in the patient with BPF • Reduce MAP & RR • Wean patient completely if possible • Partial ventilatory support • low-rate SIMV or PSV • Minimize minute ventilation • Use of permissive hypercapnia • Avoid patient positions that increase the leak • Treat bronchospasm • Consider unconventional measures • Bronchoscopic techniques • HFV • ILV

29. Independent lung ventilation

30. Independent Lung Ventilation