Section III. Revisions Approved 3/7/12 Effective 6/1/12; replaces 9/8/04; 12/1/11 and all prior versions of Protocols III.28/III.

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1 PROTOCOL III.28: Non-Invasive Positive Pressure Ventilation (NIPPV) and use of AEV Portable Ventilator EMT-BASIC EMT-INTERMEDIATE EMT-PARAMEDIC Introduction: NIPPV (CPAP/BiPAP) has been used effectively in the prehospital environment and improves emergency management of patients with acute respiratory failure due to chronic obstructive pulmonary disease (COPD), asthma, and cardiogenic/non-cardiogenic pulmonary edema. It has been shown to improve alveolar ventilation and gas exchange while decreasing preload and afterload, improving lung compliance, increasing functional residual capacity and decreasing breathing work. With increased utilization and development of NIPPV techniques, intubation for the abovementioned conditions may become obsolete and outcomes for these patients can improve. Difference Between CPAP & BiPAP/Benefits & Drawbacks: While utilization of CPAP has increased in the prehospital setting it isn t always the best choice of NPPV. CPAP provides oxygenation but not ventilation, which is the actual movement of air into the lungs CPAP is a continuous pressure provided above ambient air pressure, which helps prevent alveoli from collapsing and augment ventilation. The pressure remains relatively constant throughout each phase of the respiratory cycle, varying only slightly as the patient breathes. Because the pressure is the same throughout all phases of the respiratory cycle, the patient must overcome the pressure during expiration. CPAP is limited by the patient s ability to breathe and would be ineffective in those who cannot generate a strong enough tidal breath on their own. BiPAP also provides CPAP, but it also detects the patient s inspiratory effort and delivers greater pressure during inspiration. This is similar to squeezing the BVM while assisting a patient with breathing. At the end of the inspiratory phase, the pressure drops back to the preset level of CPAP. The Automatic Emergency Ventilator (AEV) delivers either CPAP or BiPAP. BiPAP/CPAP are beneficial because they decrease the need for endotracheal intubation, thereby lessening the complications associated with intubation. The use of these forms of NPPV does not require sedation. Complications of BiPAP/CPAP are minor and include injury to tissues where the mask makes contact with the face. III.28.1

2 Difference Between CPAP & BiPAP/Benefits & Drawbacks, (cont): Other complications include: 1) gastric distention; 2) aspiration pneumonia; 3) hypotension; 4) pneumothorax. For these reasons, NPPV should not be used on patients who have undergone recent facial surgery or patients with severe facial trauma; have on-going need to clear airway of secretions; recent gastric surgery (within one week); are experiencing GI bleeding or do not have the ability to protect their own airways; comatose/uncooperative/combative patient; patient is apneic or near apneic. Indications for use of AEV: 1. AEV is indicated for use with infants (5 kg) to adults with acute or chronic respiratory failure or during resuscitation. 2. It can be used for intubated and non-intubated patients. Controls: Menu button Mute/Cancel X button Parameter buttons Manual breath button Confirm/Select button Power switch Rotary encoder III.28.2

3 Circuits: 1. AEV ventilator circuits feature a low dead space design that minimizes CO2 re-breathing. 2. Note: dead space (circuit and HME) should never be greater than 25% of the patient s tidal volume (set or spontaneous. 3. The 2 standard ventilator circuits cover the range of patient from infant through adult. Pediatric/adult patients 20 kg through adult, minimum tidal volume 200mL; Infant/pediatric 5 though 30kg, maximum tidal volume 300mL. Connections- check the ventilator for proper operation before connecting to patient: Step 1: Connect ventilator circuit, (use test lung whenever possible), oxygen hose to 55 psi regulated output. 55 psi regulated oxygen in AC power Green hose to airway pressure transducer SpO2 not available on AEV Clear hose to exhalation valve Patient circuit corrugated tubing to gas outlet III.28.3

4 Step 2: Power Turn power switch to ON Unit performs a Self-Check and AUTO- CAL of the internal transducers. AEV then begins operation using the default settings. AUTO-CAL is performed every 5 minutes thereafter or when an altitude or temperature change is detected. Start-up settings may be changed during operation at any time. Factory Defaults: Step 3: Changing a Primary Parameter: FiO2: 21% High PIP Limit: 35 cm H2O PEEP: 5 cm H2O Vt: 500 ml BPM: 12 I:E 1:2.5 Mode: AC (V) 4. Press select to accept new value 1. Press mode parameter button adjacent to setting to be changed. 2. Current value is highlighted Turn rotary encoder to desired value III.28.4

5 Changing a Primary Parameter: Volume Targeted Operation: Change the Mode by pressing the Mode parameter button and turn rotary encoder. Modes are: Assist/Control (AC) Continuous Positive Pressure Ventilation (CPAP) PIP (Peak Airway Pressure Note: PIP cannot be adjusted during operation Tidal volume controlled directly Adjust I: E ratio Adjust breathing rate Changing a Secondary Parameter: Volume Targeted Operation: Select Breath Target: Volume (V) or Pressure (P) Press the mode parameter button twice; (V) is highlighted; then turn the rotary encoder to change to (P) and press Select button to accept change. Note: pressing the parameter button sequentially highlights the primary parameter first and then scrolls through the secondary parameters moving clockwise. Repeat these steps to return to (V). Adjust peak pressure limits: PIP (Peak Airway Pressure) High Pressure Low Pressure Adjust PEEP NOTE: trigger is PEEP compensated Adding Pressure (PS) Support: Press and hold the PIP button for 3 seconds Menu opens Adjust with rotary encoder to desired value. Range 0-60cm H 20 Press Select. Note: Value relative to PEEP pressure (PEEP + value). PS is only active in CPAP modes Using PS with CPAP (Bi-Level): Select the appropriate pressure support level (IPAP) inspiratory positive airway pressure. Choose the appropriate PEEP level (EPAP) expiratory positive airway pressure. Change mode to CPAP. Change the PPV setting to NPPV Acknowledge the NPPV application setting message.. This achieves Bi-Level. III.28.5

6 CPAP with NPPV: Press mode button to highlight the mode. Select CPAP and press Accept Press mode button twice to highlight PPV field-aev only offers NPPV Adjust with Rotary Encoder to NPPV Pop Up message will appear and ask for confirmation Press Select to confirm Select again to activate Non-invasive Positive Pressure Ventilation Algorithm OBJECTIVE: 1. To provide inspiratory/expiratory positive ventilation via mask to improve hypoxemia, reduce ventilatory muscle fatigue and to support ventilations thereby reducing patient s risk of complication from invasive ventilation. INDICATIONS: 2. Alert patient, capable of protecting airway/ handling secretions, with impending respiratory failure due to: COPD w/exacerbation Dyspnea/uncertain etiology CHF Pneumonia Asthma Water submersion event w/good respiratory drive Cystic fibrosis Neuromuscular disorder 3. Respiratory Rate 25 or greater. 4. Use of accessory muscles to breath. Assemble NPPV Equipment AEV Ventilatory Circuit CPAP Mask (S, M, L) Fixation strap Nebulizer with T-piece O 2 source General Supportive Care degrees upright patient positioning Informed consent/select appropriate mask Step 1: Connect ventilator circuit to O2 source Step 2: Power on Step 3: Change to Primary/Secondary Parameters for AEV/NPPV Operations NPPV modes CPAP BiPAP Hypoxic respiratory failure NO Set PIP: 10cm H2O Set EPAP: 5 cm H2O Set PIP: 10cm H2O FiO2: 60% to maintain SpO2 94% Adjust to achieve patient comfort Hold mask in place as the patient adjusts to the ventilatory support Encourage patient to breathe deeply Adjust mask to patient comfort/ minimize air leak Determinates if success if NPPV Decrease in work of breathing (RR < 25 b/m) üabsence of: Accessory muscle use Retractions Nasal flaring Diaphoresis Tachycardia Is patient improving on CPAP? YES Maintain NPPV parameters Is patient improving on BiPAP? YES Tritrate PIP/EPAP/ and determine NPPV success: PIP/increments of 5cm H2O to max. of 25cm H2O EPAP/increments of 2cm H2O to max. of 15cm H2O Special Considerations/Complications Patients requiring bronchodilator therapy with NPPV/applicable protocol ü Bronchodilators delivered by nebulizer t-piece in line with NPPV Patients must be monitored carefully for worsening respiratory distress, tachypnea, SpO2; be prepared to support hypoxia/ hypoventilation refractory to NPPV It is extremely important for air seal to be tight Adverse hemodynamic effects from NPPV are unusual, although preload reduction and hypotension may occur NO III.28.6

7 Indications for use of AEV for positive pressure ventilation: A. General: Anytime the patient s ventilations would need to be assisted with a bag-valve mask, bag to endotracheal tube or appropriate adjunct Contraindications: A. Patients with suspected pneumothorax or tension pneumothorax. B. Patient with elevated pulmonary pressure syndrome, (water ascent injury). Technique: A. Determine need for assisted ventilations. B. Establish airway and employ conventional BLS airway adjuncts and ventilatory support according to protocol. C. Perform oral, nasal tracheal intubation or King Airway insertion according to protocol. D. Tube shall be secured and proper placement confirmed, using a bag-valve device, in accordance to Protocol III.5/6/42. E. Assemble components of AEV. F. Turn the Power switch on to initiate the self check and start the ventilator. When self check is complete, operation will begin at default values. G. Remove bag-valve device, and attach the outlet port of the ventilator assembly to the endotracheal tube. H. Select pre-set parameters for adult or pediatric assist ventilation. I. Once the ventilator is attached and is operating, assess for physiologic changes. These include equal rise and fall of the chest, condensation in the endotracheal tube on exhalation, improvement in the patient s color, and improvement in the patient s respiratory distress or failure. J. EtCO 2 must be rechecked for any change. If the waveform continues to show a normal pattern of rapid upstroke with exhalation, exhalation plateau, and rapid downstroke with inhalation, no further repeat confirmation is required. If at any time, the capnograph waveform is abnormal, initiate procedures to confirm correct endotracheal tube position. III.28.7

8 Safety measures: A. Initial airway management and ventilation cannot and must not be compromised while setting up the AEV. B. If problems arise during AEV use or if there is uncertainty about the adequacy of oxygenation and ventilations with the AEV, then STOP and ensure oxygenation and ventilation with the usual methods. C. Using a mechanical ventilation device will remove the ability to determine early changes in pulmonary compliance, such as may be detected using a bag-ventilation technique. D. The incidence of a pneumothorax is increased in the presence of penetrating chest trauma. E. As a general guideline, in an UNINTUBATED ADULT patient, tidal volumes of below 800 ml should NOT be provided. F. Using AEV will remove the ability to determine early changes in pulmonary compliance, such as may be detected using bag-ventilation technique. G. Gastric distention can cause resistance to mechanical ventilation. Gastric distention should be suspected in patients with an acutely distended abdomen after difficult endotracheal intubation, especially if CPR was performed. To relieve gastric distention insert nasogastric tube immediately and apply low suction until distention is relieved. If the nasogastric tube does not relieve abdominal distention, a gastric rupture should be suspected. III.28.8