General understanding of non invasive ventilation. Difference of CPAP and BiPAP, definition, and settings.
Size: 9.04 MB
Language: en
Added: Aug 17, 2021
Slides: 29 pages
Slide Content
Non-Invasive Ventilation (NIV) & Non-invasive Positive Pressure Ventilation (NPPV) Presented By Michael S. Allen, RRT Updated: October 24 , 2019 This presentation is intended for educational purpose only .
NIV & NPPV Non-Invasive Ventilation (NIV): Term used to describe CPAP but can also be used for BiPAP Non-invasive Positive Pressure Ventilation (NPPV): Positive pressure used to ventilate (via BVM, BiPAP, or IPPB device)
Leaning Objective What is CPAP (aka NIV) What is BiPAP (aka NPPV) What patient type will use CPAP or BiPAP Indications & Contraindications Device types Implementing Therapy Patient Success and Failure
What is CPAP? CPAP = Continuous Positive Airway Pressure Air flow that is given as a constant pressure, measured in cmH 2 0. (see next slide) Patient will breathe normally above set pressure. Note: this mode is only for a spontaniously breathing individual. CPAP is used for OSA, Atelectasis , CHF, and improving oxygenation. (see next slide) CPAP does not help with ventilation (CO 2 removal). PEEP or EPAP = Positive End Expiratory Pressure, which is the alveolar pressure before inspiratory flow begins. Adding PEEP helps decrease the amount of work required to initiate a breath. It also helps to decrease atelectasis .
What is CPAP continued: CPAP = Continuous Positive Airway Pressure Air flow that is given as a constant pressure, measured in cmH20. By maintaining a PEEP, the CPAP helps to expand the alveoli thus increasing surface area for gas exchange improving oxygen delivery. CPAP can increase intrathoracic pressure which will decrease preload, thereby decreasing cardiac workload
What is CPAP continued: Indications CPAP: Decreases with low functional residual capacity (FRC) People with OSA Pulmonary edema Fluid overload/Congestive heart failure Augment oxygenation in the presence of refractory hypoxemia [PaO2 < 60mm HG, or SaO 2 < 90% with FiO 2 > 60%] Meconium Aspiration Syndrome Weaning from mechanical ventilation Contraindications CPAP: Patient is in respiratory arrest Patient is suspected of having a pneumothorax Patient has a tracheostomy Patient is vomiting Patient has to be spontaneously breathing – device will not breathe for them.
What is NPPV? BiPAP = Bi-Level Positive Airway Pressure Bi-level : Cycled ventilation between Inspiratory Positive Airway Pressure (IPAP) and Expiratory Positive Airway Pressure (EPAP/PEEP). Note: BiPAP is a ® ™ of Respironics Corporation and Bi-level or NIV/NPPV is the non-trademark verbiage. Uses an exhalation pressure (EPAP or PEEP) to keep airways open, but also uses an inspiratory pressure (IPAP) to aid in an opening pressure to assist the patient in taking a deeper breath in. Pressure support (PS) is the difference between the IPAP and the EPAP. With PS, the lungs will be able to expand more to allow increased ventilation (clearing of CO 2 ). 20 10 IPAP = 12 EPAP = 4 PS = 8
NPPV Use Indications Bi-level: Respiratory failure due to accessory muscle fatigue Acute hypercapnia/hypercarbia & CO 2 retention COPD to decrease airway resistance, thereby decreasing work of breathing required to take in an adequate tidal volume May be used in hypoventilation syndrome for the morbidly obese patient in acute situations Contraindications Bi-level: Decreased LOC that prevents the patient’s ability to protect his/her own airway Inability to maintain a patent airway or adequately clear secretions Non-compliant patient Gastric distention Increased intracranial pressure Pulmonary barotraumas Cardiovascular compromise
“Bi-level” IPAP & EPAP settings IPAP setting can be adjusted to achieve the desired CO 2 level and tidal volume. Pressures above 20 cm H 2 O usually are not well tolerated and increase the risk of gastric distension and vomiting. Most patients will swallow some air during noninvasive ventilation and it is usually not a problem unless peak pressure exceeds 20 cmH2O. In most patients, the placement of a nasogastric tube is not necessary. Typically, start EPAP at 4 cm H 2 O and increase to meet oxygenation goals. Pressure support equals the difference between IPAP and EPAP. Similar to conventional ventilation, this value affects the volume delivered to the patient. A backup rate may be provided in the event the patient becomes apnic . If the backup rate is set to high, it may override the patient’s own effort to initiate a breath. This could trigger the apnea alarm to sound. Consider setting the back up rate to 8.
Suggested Bi-level settings Values are from an ABG (not VBG): These NPPV settings are not an absolute, but are suggested settings. If using a VBG during NPPV, keep SvO 2 at 75%; PvO 2 at 40 mmHg pH PaCO 2 PaO 2 HCO 3 - BiPAP 7.38 65 80 40 compensated, no intervention 7.32 50 60 24 10/5 7.30 65 55 28 12/6 7.28 70 50 30 14/8 7.20 120 48 43 16/10 If Ph lower than 7.20, consider intubation. Also evaluate patient’s LOC, RR, and WOB. ABG vs. VBG … the controversy: https://epmonthly.com/article/blood-gases-abg-vs-vbg/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2660085/ https://www.aarc.org/wp-content/uploads/2017/09/clia-faqs.pdf http://www.rcjournal.com/cpgs/pdf/blood_gas_hexometry.pdf https://www.respiratorytherapyzone.com/abg-interpretation/ ABG VBG pH 7.35-7.45 pH 7.32-7.42 PaCO 2 35-45 PvCO 2 40-52 PaO 2 80-100 PvO 2 30-48 HCO 3 - 22-28 HCO 3 - 19-25 SaO 2 95-100% SvO 2 50-75%
What is AVAPS? Indications Average Volume Assured Pressure Support (AVAPS) Improve ventilation efficacy Recognize changing patient needs and then automatically make adjustments For obesity hypoventilation syndrome, OSA, COPD, neuromuscular disorders, Contraindications AVAPS: Fluid overload CHF Decreased LOC Patient lack of spontaneous trigger A non-invasive positive pressure ventilation (NPPV) that adjust the pressure support (PS) to maintain a target average ventilation over several breaths. AVAPS adjust PS and the respiratory rate to reach a defined target with the goal of stabilizing the PaCO 2 , which relates directly to alveolar ventilation. Theoretical benefits of VAPS over BiPAP include maintaining volumes in the setting of altered patient effort based on sleep stage or altered lung mechanics related to position. Less PS while awake may increase comfort and aid sleep onset, reduce the risk of barotrauma, and provide lower pressures most of the time. https://www.pulmonarychronicles.com/index.php/pulmonarychronicles/article/view/438/971
Home Units CPAP Unit examples: …… typically used for OSA or COPD Keep oxygen port connected, or, remove from line if not in use.
Hospital Units … typically used to decrease PaCO 2 Bi-Level (BiPAP) What we use at WVMC: The Vision : Cap exhalation port on circuit. Requires calibration test before placing on patient. The V.60 : Can also do AVAPS. Can transport patient w/o taking off mask. BiPAP S/T-D : No longer being used at WVMC Full Face Mask : Small, Medium, Large Is the only style we use at WVMC
Heated Humidified High Flow Nasal Canula Used for improving oxygenation, but can also be used to decrease WOB and decrease CO 2 High Flow Oxygen (O 2 only) Heated Humidified High Flow Oxygen (O 2 & alternate for NIV) http://rc.rcjournal.com/content/58/1/98 https://ccforum.biomedcentral.com/articles/10.1186/s13054-016-1263-z https://www.nejm.org/doi/full/10.1056/NEJMoa1503326 http://www.rtmagazine.com/2013/09/high-flow-oxygen-does-it-make-a-difference/
Who Needs NPPV ? <> Pearls : * Positive Pressure is not everything . Do not forget medical management . * Bi-level ventilation is an early “go-to” in moderate to severe COPD exacerbations. * Experienced RTs are critical to the success of non-invasive ventilation. * Once applied, reassess your patient frequently and be ready to adjust. * Can be used to stave off intubation. * Consider for pre-oxygenation prior to intubation. <> Pitfalls : * Positive pressure can cause hypotension and decompensation if blindly applied. * Do not place a pressure mask on a damaged face or a fluid filled mouth. * Do not delay necessary intubation. * Do not let your patient Auto-PEEP. * Your severely acidotic patient is at high risk for failure; be ready to intubate . * If your patient is not awake, then the patient should be intubated .
Who Needs NPPV ? <> Who Needs It? : * Patients with moderate to severe COPD exacerbations. * Patients with cardiogenic pulmonary edema with increased WOB or hypercapnia . * Patients with isolated blunt thoracic trauma. * The immunocompromised patient with hypoxic respiratory failure. * Patients who require pre-oxygenation prior to intubation. <> Who Does Not? : * Altered Mental Status. * Facial Trauma/Can’t Handle their own secretions. <> Gray Zones : * Asthma. * Neuromuscular Disease. * Undifferentiated Hypoxic Respiratory Failure.
Implementing NPPV HOB up 45 degrees Explain the process Select appropriate mask Top: bridge of nose. Bottom: have patient open mouth, mask should fit just below lip and above chin. Note that the above is for hospital full-face mask. There are hundreds of styles & fittings from different vendors that patient’s may use at home. Clinician attitude, approach, and knowledge affects patient’s cooperation
Implementing NPPV Adjust rise time Determines how fast the ventilator rises from the baseline to the target pressure Set alarms High and low pressure Low minute ventilation High and low rate
Monitoring the Patient Continue to coach and reassure patient Monitor vital signs and accessory muscle activity Maintain SpO 2 > 90% Adjust ventilator settings to improve patient-to-ventilator synchrony Look for improvements in gas exchange within 1 to 2 hours Note: WVMC policy requires a continuous pulse oximeter to be in use. If to substitute a patient’s own unit (that they were unable to bring in from home), then continuous pulse oximetry is not required. Literature supports maintaining SpO 2 92-96% with supplemental oxygen, and 88-92% for a person who is a CO 2 retainer.
Monitoring the Patient Check mask comfort and excessive leaks Check mask for correct size and fit Check mask and headgear for proper, even adjustment Switch mask style Air Leak 0-6 Lpm = Mask may be too tight 7-25 Lpm = Just right 26-60 Lpm = Adjust and monitor >60 Lpm = Caution
Patient Success APACHE score < 20 Glasgow Coma score > 12 Hypercapnia, but not excessive PaCO 2 < 50 pH > 7.25 T he best predictor of success, however, is a favorable response in gas exchange and vital signs within the first one to two hours of initiating noninvasive ventilation.
NPPV Failure Lack of improvement in arterial blood gases Severe acidosis (pH < 7.2) Hypercapnia (PaCO 2 > 60 mm Hg) Hypoxemia (PaO 2 /FiO 2 < 200 mm Hg) Tachypnea (> 30 BPM) Note: If the patient's condition fails to improve with in the first 2 hours, intubation and mechanical ventilation may be indicated. Noninvasive ventilation failure is identified with worsening arterial blood gases, severe acidosis, hypercapnia, hypoxemia and tachypnea.
Oral Intake Remove interface As tolerated by patient Provide supplemental oxygen Avoid eating 2-3 hours before bedtime to avoid aspiration
Mask interface issues Discomfort Check fit, adjust straps, change interface Excessive air leaks Realign interface, check strap tension, change to different size mask Nasal bridge redness or ulceration Use artificial skin, minimize strap tension, use spacer, alternate interface Skin irritation or rashes Use skin barrier lotion and/or topical corticosteroids, Properly clean mask Claustrophobic reactions Sedate with caution ( ie : Ativan , Morphine)
Airflow issues Nasal congestion Try nasal steroids, decongestant, antihistamine or humidification Nasal or oral dryness Add humidification, nasal saline, oral/nasal hygiene or decrease leak Sinus or ear pain Lower inspiratory pressure Gastric inflation Avoid excessive inspiratory pressures >20 cm H 2 O) Eye irritation Check mask fit, readjust headgear straps Failure to ventilate Use sufficient pressures, optimize patient-ventilator synchrony
When to call the RT: The Machine Alarms The heater is out of water The patient is coming OFF the device The patient needs to go back ON the device Mask fitting error or patient discomfort Some devices can be used in transport DO … Ensure device is connected to the oxygen outlet DO … Ensure power is connected Note scope of practice : CNAs should not be turning on/off a device, nor taking a patient interface off for a bathroom or drink break. Only a RN that has had a competency check-off should be making any BiPAP or patient interface adjustments. “OSBN does not allow for tasks to be delegated that require the RN assessment as integral to the task.” Shannon Carefoot Check with your RT to see if patient should be NPO and/or if they can tolerate being off the NPPV support.
Other References and Resources http://www.emdocs.net/bi-level-ventilation-needs-doesnt-pearls-pitfalls Philips Respironics TM Vision ® Workshop – Initiating NIV https://www.usa.philips.com/healthcare/solutions/breathing-and-respiratory-care https://www.usa.philips.com/healthcare/product/HCDS1160S/bipap-avaps-non-invasive-ventilator/documentation http://rc.rcjournal.com/content/59/7/e105
Questions ? Hands on skills… 1. Locate the following values on the machine’s display: Tidal Volume (V T ) “leak” value Locate IPAP/EPAP Locate patient respiratory rate 2. If time, get a test mouthpiece and feel difference of CPAP vs. BiPAP