Mechanical ventilators- Applications and Usage

The Medical Ventilators are also known as Mechanical Ventilators, Artificial Ventilators etc. We will henceforth refer all these as Ventilators.
When a patient breathes on its own it is known as Spontaneous Breathing and when the patient is unable to breathe on its own we use a device called Ventilator which helps the patient breathe artificially. This is called Mechanical Ventilation and is a method to mechanically assist the patient to breathe and in extreme cases replace the entire breathing process. Spontaneous breathing is done by a process called Respiratory System.

1. Let’s Learn Health Technology in Health Technology Management Series Topic-Mechanical Ventilators Health technology  is defined by the World  Health  Organization as the "application of organized knowledge and skills in the form of devices, medicines, vaccines, procedures, and systems developed to solve a  health  problem and improve quality of lives“

2. Mechanical Ventilators Compiled by Dr. S.B.Sinha - Ex President Biomedical Engineering Society of India Health Technology Management Series

3. Mechanism of breathing

4. Mechanical Ventilators- What??

5. Types of Ventilators

6. Components of a ventilator

7. Common ventilator components Humidifier Patient Curcuit Air and Oxygen Hose Air/ Oxygen Mixer (Blender)

8. Basic Ventilator Parameters

9. Ventilator alarms

10. Normal parameters settings of ventilator

11. Modes of mechanical ventilator

12. Ventilation phases

13. Ventilator phase variables

14. Modes in ventilation

15. BREATH TYPES

16. BREATH TYPES

17. CMV- Controlled mandatory ventilation

18. CMV-Controlled mandatory ventilation

19. Assist control mandatory ventilation In Asst Control Mode the patient tries to breathe but the breathing is still delivered by the patient. Patient is not allowed to breath on its own.

20. SIMV-Synchronised intermittent mandatory Ventilation This mode is used when the patient has started breathing. Thus patient breathing is synchronized with the ventilation by the ventilator. The patient will be allowed to breathe and when it is unable to breathe the ventilator will provide the breathing. The patient's bpm is set as per requirement and this breathing is guaranteed to the patient but this consists of partially the patients breathing and partially by the Ventilator.

21. SIMV-CONTD. The Ventilator delivers either patient triggered assisted breath or time triggered mandatory breaths in a synchronised manner so as to avoid ventilator fighting with the patient. If the patient breathes between mandatory breaths, the ventilator will allow patient to breath by opening the demand (inspiratory) valve but not offering any inspiratory assistance.

22. PCV- Pressure controlled ventilation In his Mode the inspiration Cycle maintains a pressure limit set by the machine. The Volume may not be guaranteed but pressure will never exceed the Maximum pressure set in the Ventilator. In Pressure Controlled Mode inspiration is terminated when a specific airway pressure has been reached. The ventilator delivers a preset pressure; once this pressure is achieved, end inspiration occurs.

23. PRESSURE SUPPORT VENTILATION

24. Cpap- continuous positive airway pressure

25. BIPAP- BILEVEL POSITIVE AIRWAY PRESSURE

26. CPAP AND BIPAP WAVE FORM

27. High frequency ventilators - In some advanced ventilators this mode is present. High-frequency ventilators use small tidal volumes (1 to 3 mL/kg) at frequencies greater than 100 breaths/minute. The high-frequency ventilator accomplishes oxygenation by the diffusion of oxygen and carbon dioxide from high to low gradients of concentration

28. INSTALLATION OF A VENTILATOR

29. QUICK TESTING BEFORE USE

30. TROUBLESHOOTING COMMON PROBLEMS.

31. PREVENTIVE MAINTENANCE Cleaning- a) Remove any dust, dirt, water, waste matter, tape and paper daily. b ) Clean inside and outside with damp clothes and dry off weekly c ) Remove dirt from wheels and other moving parts on a weekly basis. Audiovisual Checks: DAILY a. If any leak is audible, check with soapy solution. b. Check all seals, connectors, adapters and parts are tight. c. Check all moving parts move freely, all holes are unblocked. WEEKLY a) Check connections for leaks with soap solution and dry off. b) Check all fittings and valves for proper assembly. c) Replace and deteriorated tubing and hoses. d) If seal, plug, sockets are damaged replace them.

32. CALIBRATION FOR PRESSURE 1. Construct a manometer to measure pressure in centimeters of H2O. a. Use a large non-inflatable jug as the reservoir. Most water jugs will work. b. Fill the jug half-full with water. c. Insert the patient output from the ventilator into the plastic jug. Also insert one end of the clear plastic tubing into the plastic jug. The end of the plastic tube should be near the bottom. d. Seal the tubes with latex gloves and tape. Insure that no air can escape from the jug opening. 2. Set the pressure limit on the ventilator. Record this pressure in Table 1 below. 3. Hold the clear plastic tubing straight up. Use a tape measure to measure the peak height of the water in cm H2O. Measure from the water level in the jug to the maximum height reached in the clear plastic tubing. Record this measurement . The height of the water is the pressure. 4. Repeat Steps 2-3 for four settings of pressure. 5. To determine if the ventilator is accurate enough, show your table to the physician that uses the ventilator. The set and measured reading should match.

33. CALIBRATION FOR VOLUME

34. Thank you- q/a( Image-EE Times )