Mechanical ventilator for nurses 08.02.19

simple ppt

1.   Mechanical ventilator

2.   mechanical ventilator A mechanical ventilator is a positive- or negative-pressure breathing device that can maintain ventilation and oxygen delivery for a prolonged period

3. Mechanical ventilation Mechanical ventilation The use of a ventilator to move room air or oxygen-enriched air into and out of the lungs mechanically to maintain proper levels of oxygen and carbon dioxide in the blood. Types of ventilators include negative-pressure and positive-pressure ventilators. Various ventilator modes are adjusted to the client’s individual needs.

4. PURPOSE To maintain adequate ventilation To maintain desired fio2 To maintain desired tidal volume To maintain a pattern airway To support the lung To Decrease work of breathing To Increase alveolar ventilation To Maintain ABG values within normal range To Improve distribution of inspired gases

5. Indications of mechanical ventilation Acute respiratory failure Apnoea or impending inability to breathe Airway Compromise – airway patency is in doubt or patient may be at risk of losing patency Severe hypoxia Respiratory muscle fatigue Cardiac Insufficiency Neurological problems Therapeutic and prophylatic Acute lung injury

6. Clinical parameters Respiratory Rate ˃ 35/min Tidal volume <5ml/kg Vital capacity <(15ml/kg body wt ) PaO2 ˃50mm of Hg with FiO2 ˃ 0.60 PaCO2 ˃ 55mm of Hg with pH ˃7.25

7. Types 1. Pressure-cycled ventilator : The ventilator pushes air into the lungs until a specific airway pressure is reached; it is used for short periods, as in the postanesthesia care unit . 2 . Time-cycled ventilator : The ventilator pushes air into the lungs until a preset time has elapsed; it is used for the pediatric or neonatal client.

8. 3. Volume-cycled ventilator a. The ventilator pushes air into the lungs until a pre-set volume is delivered. b. A constant tidal volume is delivered regardless of the changing compliance of the lungs and chest wall or the airway resistance in the client or ventilator.

9. 4. Microprocessor ventilator a. A computer or microprocessor is built into the ventilator to allow continuous monitoring of ventilatory functions, alarms, and client parameters. b. This type of ventilator is more responsive to clients who have severe lung disease or require prolonged weaning

10. Modes of ventilation 1 . Controlled a. The client receives a set tidal volume at a set rate . b. Used for clients who cannot initiate respiratory effort . c. Least used mode; if the client attempts to initiate a breath, the ventilator blocks the effort. 2. Assist-control a . Most commonly used mode b. Tidal volume and ventilatory rate are preset on the ventilator

11. 3. Synchronized intermittent mandatory ventilation (SIMV ) a. Similar to assist-control ventilation in that the tidal volume and ventilatory rate are preset on the ventilator. b. Allows the client to breath spontaneously at her or his own rate and tidal volume between the ventilator breaths c. Can be used as a primary ventilatory mode or as a weaning mode. d. When SIMV is used as a weaning mode, the number of SIMV breaths is decreased gradually, and the client gradually resumes spontaneous breathing

12. Controls and settings

13. Controls and Settings Tidal volume The volume of air that the client receives with each breath. Rate The number of ventilator breaths delivered per minute. Sighs The volumes of air that are 1.5 to 2 times the set tidal volume, delivered 6 to 10 times per hour; may be used to prevent atelectasis .

14. Fraction of inspired oxygen (FIO2) The oxygen concentration delivered to the client; determined by the client’s condition and ABG levels. Peak airway inspiratory pressure The pressure needed by the ventilator to deliver a set tidal volume at a given compliance. Monitoring peak airway inspiratory pressure reflects changes in compliance of the lungs and resistance in the ventilator or client.

15. Continuous positive airway pressure The application of positive airway pressure throughout the entire respiratory cycle for spontaneously breathing clients. Keeps the alveoli open during inspiration and prevents alveolar collapse; used primarily as a weaning modality. No ventilator breaths are delivered, but the ventilator delivers oxygen and provides monitoring and an alarm system; the respiratory pattern is determined by the client’s efforts.

16. Positive end-expiratory pressure (PEEP) Positive pressure is exerted during the expiratory phase of ventilation, which improves oxygenation by enhancing gas exchange and preventing atelectasis. The need for PEEP indicates a severe gas exchange disturbance. Higher amounts of PEEP (more than 15) increase the chance of complications, such as barotrauma tension pneumothorax.

17. Pressure support The application of positive pressure on inspiration that eases the workload of breathing. May be used in combination with PEEP as a weaning method. As the weaning process continues, the amount of pressure applied to inspiration is gradually decreased.

18. Causes of Ventilator Alarms High-Pressure Alarm Increased secretions are in the airway. Wheezing or bronchospasm causes decreased airway size. The endotracheal tube is displaced. The ventilator tube is obstructed because of water or a kink in the tubing. Client coughs, gags, or bites on the oral endotracheal tube. Client is anxious or fights the ventilator. Low-Pressure Alarm Disconnection or leak in the ventilator or in the client’s airway cuff occurs. The client stops spontaneous breathing.

19. Complications of ventilator 1. Hypotension caused by the application of positive pressure , which increases intrathoracic pressure and inhibits blood return to the heart 2. Respiratory complications such as pneumothorax or subcutaneous emphysema as a result of positive pressure 3. Gastrointestinal alterations such as stress ulcers

20. 4. Malnutrition if nutrition is not maintained 5. Infections 6. Muscular deconditioning 7. Ventilator dependence or inability to wean 8.Ventilator associated pneumonia 9.Baro trauma

21. Weaning: Process of going from ventilator dependence to spontaneous breathing 1. SIMV a. The client breathes between the preset breaths per minute rate of the ventilator. b. The SIMV rate is decreased gradually until the client is breathing on his or her own without the use of the ventilator .

22. 2. T-piece a. The client is taken off the ventilator and the ventilator is replaced with a T-piece or continuous positive airway pressure, which delivers humidified oxygen. b. The client is taken off the ventilator for short periods initially and allowed to breathe spontaneously. c. Weaning progresses as the client is able to tolerate progressively longer periods off the ventilator.

23. 3. Pressure support a. Pressure support is a predetermined pressure set on the ventilator to assist the client in respiratory effort. b. As weaning continues, the amount of pressure is decreased gradually. c. With pressure support, pressure may be maintained while the preset breaths per minute of the ventilator gradually are decreased.

24. Nursing care

25. Nursing care 1 . Assess vital signs, lung sounds, respiratory status, and breathing patterns (the client will never breathe at a rate lower than the rate set on the ventilator). 2. Monitor skin color , particularly in the lips and nail beds. 3. Monitor the chest for bilateral expansion. 4. Obtain pulse oximetry readings. 5. Monitor ABG results .

26. 6. Assess the need for suctioning and observe the type, color , and amount of secretions. 7. Assess ventilator settings. 8. Assess the level of water in the humidifier and the temperature of the humidification system because extremes in temperature can damage the mucosa in the airway. 9. Ensure that the alarms are set. 10. If a cause for an alarm cannot be determined, ventilate the client manually with a resuscitation bag until the problem is corrected.

27. 11. Empty the ventilator tubing when moisture collects. 12. Turn the client at least every 2 hours or get the client out of bed, as prescribed, to prevent complications of immobility. 13. Have resuscitation equipment available at the bedside. 14.Hyperventilate the patient before suctioning 15. Provide call bell to patient . 16.Provide note and pen to the patient to communicate his needs.