Indications of Mechanical Ventilation.pptx

Mechanical ventilation, criteria to inititiate mechanical ventilation

1. Need for mechanical ventilation Smrithi Rajeev M.Sc. Respiratory Therapy

2. What is mechanical ventilation? A useful modality for patients who are unable to sustain the level of ventilation necessary to maintain the gas exchange functions Indicated in conditions due to physiologic changes (e.g., deterioration of lung parenchyma), disease states (e.g., respiratory distress syndrome), medical/surgical procedures (e.g., post anesthesia recovery), and many other causes (e.g., head trauma, drug overdose) leading to ventilatory failure or oxygenation failure. Can be short term to long term and from acute care in the hospital to extended care at home.

3. indications Apnea Impending respiratory failure Acute exacerbation of COPD Acute severe asthma Neuromuscular disease Acute hypoxemic respiratory failure, Heart failure and cardiogenic shock, Acute brain injury

4. (1)Increased airway resistance (2) Changes in lung compliance (3) Hypoventilation (4) V/Q mismatch (5) Intrapulmonary shunting (6) Diffusion defect

5. Non invasive ventilation Alternative to invasive positive pressure ventilation and may be a means of avoiding endotracheal intubation. Treatment of choice for acute-on-chronic respiratory failure unless cardiovascular instability is also a factor. The use of NIV for acute-on-chronic respiratory failure has been shown to reduce the need for intubation, reduce complications of ventilation, shorten the hospital stay, and reduce hospital mortality rates

6. NIV may also be beneficial for patients with ARF associated with cardiogenic pulmonary edema . Acute-on-chronic hypercapnic respiratory failure in patients with musculoskeletal problems (e.g., kyphoscoliosis and post polio syndrome) may be well suited to NIV. NIV may be an effective method of resting the ventilatory muscles and averting invasive ventilation in this latter group of patients. However, patients with neuromuscular disorders who develop acute respiratory acidosis and evidence of muscle weakness that progressively worsens (decreasing MIP and VC) require prompt intubation to prevent ARF .

7. COPD CARDIOGENIC PULMONARY EDEMA BRONCHIAL ASTHMA COPD FACILITATION OF WEANING DO NOT INTUBATE

8. Hess D: Noninvasive positive pressure ventilation: predictors of success and failure for adult acute care application, Respir Care 42:424, 1997. Nava S, Ceriana P: Causes of failure of noninvasive mechanical ventilation, Respir Care 49:295, 2004

9. Variety of interfaces available Nasal masks Oronasal masks Total face mask Helmets Nasal pillows Mouthpiece with lip seal

10. SET UP AND PREPARATION OF NIV

11. Always start from low  adjust according to patient requirement FiO 2 requirement adjust the flow based on the SpO 2 and PaO 2 Initiate EPAP- 4-5 cmH 2 0 and IPAP- 8-10cmH 2 Adjust the IPAP and EPAP based on the ventilation, oxygenation and monitor for patient comfort

12. WHEN TO SWITCH INTO INVASIVE i . Failure of NIPPV: unchanging dyspnea/respiratory distress or worsening ABG within 2 hours. ii. Severe acidosis (pH < 7.2) and worsening hypercapnia (Paco, > 60 mm Hg). iii. Life-threatening hypoxemia (Pao/ Fio , < 200 mm Hg). iv. Altered mental status or inability to clear secretions and to pro- tect the airway. v. Hemodynamic instability

13. INVASIVE MECHANICAL VENTILATION Invasive mechanical ventilation is defined as  the delivery of positive pressure to the lungs via an endotracheal or tracheostomy tube .  Invasive mechanical ventilation is most often used to fully or partially replace the functions of spontaneous breathing by performing the work of breathing and gas exchange in patients with respiratory failure

14. indications Mechanical ventilation is indicated when the patient cannot maintain spontaneous ventilation to provide adequate oxygenation or carbon dioxide removal. The clinical conditions leading to mechanical ventilation can be grouped into four areas: (1) acute ventilatory failure; (2) impending ventilatory failure; (3) severe hypoxemia; and (4) prophylactic ventilatory support

15. Acute ventilatory failure The primary indication for mechanical ventilation is acute ventilatory failure. This is defined as a sudden increase in the PaCO2 to greater than 50 mm Hg with an accompanying respiratory acidosis (pH < 7.30)

16. Impending ventilatory failure Impending ventilatory failure occurs when a patient can maintain only marginally normal blood gases, but only at the expense of a significantly increased work of breathing Development of impending ventilatory failure is dependent on the balance of metabolic needs and work of breathing

17. Severe hypoxemia Hypoxemia is a common finding in lung diseases. When hypoxemia is severe, mechanical ventilation may be necessary to support the oxygenation deficit. ALI, ARDS, pulmonary edema, and carbon monoxide poisoning are examples that often require ventilatory support for the primary purpose of oxygenation

18. Prophylactic ventilatory support Prophylactic ventilatory support is provided in clinical conditions in which the risk of pulmonary complications, ventilatory failure, or oxygenation failure is high. In addition, prophylactic or early commitment of the patient to the ventilator can minimize hypoxia of the major body organs. It can also reduce the work of breathing and oxygen consumption and thus preserve and rest the cardiopulmonary system, and promote patient recover

19. References David Chang, James M Heirs; Chapter 8; Initiation of Mechanical Ventilation, Clinical Application of Mechanical Ventilation J M Cairo; Pilbeam’s Mechanical Ventilation; Physiological and clinical application ; Chapter 4, Establishing the need for mechanical ventilation