Part II: Introduction to Noninvasive Positive Pressure Ventilation in the Acute Care Setting By: Susan P. Pilbeam, MS, RRT, FAARC John D. Hiser, MEd, RRT, FAARC Ray Ritz, BS, RRT, FAARC American Association for Respiratory Care December, 2006

Benefits of Using NPPV NPPV provides greater flexibility in initiating and removing mechanical ventilation Permits normal eating, drinking and communication with your patient Preserves airway defense, speech, and swallowing mechanisms

Benefits of Using NPPV Compared to Invasive Ventilation Avoids the trauma associated with intubation and the complications associated with artificial airways Reduces the risk of ventilator associated pneumonia (VAP) Reduces the risk of ventilator induced lung injury associated with high ventilating pressures

Other Benefits of Using NPPV Reduces inspiratory muscle work and helps to avoid respiratory muscle fatigue that may lead to acute respiratory failure Provides ventilatory assistance with greater comfort, convenience and less cost than invasive ventilation Reduces requirements for heavy sedation Reduces need for invasive monitoring

Additional Benefits of NPPV in the Acute Care Setting Preserves the ability to communicate Enhances patient comfort

Examples of Patient Problems that may Benefit from NPPV in the Acute Care Setting Acute Exacerbation of COPD Hypoxemic Respiratory Failure/ARDS Community Acquired Pneumonia (CAP) Asthma Immunocompromised States Acute Cardiogenic Pulmonary Edema (CPE) - when hypercapnia is present.

Additional Examples of Disorders in which NIPPV by Nasal or Face Mask has been Used Neuromuscular disorders Central alveolar hypoventilation Cystic fibrosis Bronchiectasis Postoperative complications Postextubation failure in difficult-to-wean patients Do-not-intubate patients

First Step: Selection Criteria for Patients in the Acute Care Setting Consider the patient's diagnosis, clinical characteristics and the risk of failure of the procedure Applying NPPV too early may be unnecessary for patients with mild respiratory distress On the other hand, applying NPPV when a patient has already deteriorated to severe respiratory failure may potentially delay life-saving intubation and ventilation

Establishing the Need for Ventilation Signs and Symptoms of Distress in the Adult –Tachypnea (respiratory rate >24 breaths/min) –Accessory muscle use, and paradoxical breathing –ABG results: pH 45 mm Hg, or PaO 2 /FiO 2 < 200

Patient Medical History The underlying patient disorder must be taken into account For example, does the patient have acute respiratory failure with a history of COPD. Or, does the patient have acute congestive heart failure with an elevated CO 2 ? Next exclusionary criteria must be evaluated

Second Step: Exclusionary Criteria Respiratory arrest (apnea) or the need for immediate intubation Unable to protect the airway (impaired cough or swallowing) Excessive secretions Hemodynamic instability Agitated and confused patients Paradoxical breathing Upper airway obstruction

Additional Exclusionary Criteria Facial deformities or conditions that prevent mask fit, e.g. facial burns, severe facial trauma, craniofacial surgery, fixed anatomic abnormalities of the nasopharynx J Crit Care 2004 Vol. 19:82-91

Additional Exclusionary Criteria Untreated pneumothorax Uncooperative or unmotivated patients Brain injury with unstable respiratory drive Other major organ involvement – for example, severe hemorrhaging Recent esophageal or gastric surgery (relative contraindication) Finally, irreversibility of disorder

NPPV Initiated Once the patients signs and symptoms are evaluated, And the underlying disorder is considered, And finally exclusionary criteria are eliminated, IF Then NPPV may be justified IF the acute respiratory failure is likely to resolve in a few days.

Interfaces A variety of interfaces can be used to provide NPPV This section will focus on those devices used in the acute care setting

Nasal Masks Thin flexible & bridge material Dual density foam bridge forehead support Dual flap cushion 360  swivel standard elbow Respironics Contour Deluxe ™ Mask

Fitting Nasal Masks Nasal fitting template Choose the smallest mask without obstructing the nostrils Courtesy of Respironics

Anatomic Landmarks for Nasal Mask Fit Anatomic Landmarks Anatomic Landmarks a)Sides of nose b)Bridge of nose (caution) c)Above the lip Courtesy of Respironics

Nasal Mask Fit Top of the mask: placed just above the junction of the nasal bone and the cartilage (dorsum of the nasal bridge) The fit should be not pinch the nose at the side The lower part of the mask fits just above the upper lip A common error is to pick a mask that is too large

Nasal Mask Fit (continued) Foam “bridges” that attach to the end of the mask and rest on the forehead help reduce pressure on the bridge of the nose

Advantages of Nasal Masks Less risk of aspiration Enhanced secretion clearance Less claustrophobia Easier speech Less dead space

Disadvantages of Nasal Masks Mouth leak Less effectiveness with nasal obstruction Nasal irritation and rhinorrhea Mouth dryness

Full Face Masks Most often successful in the critically ill patient Respironics PerformaTrak ® Full Face Mask Entrainment valve Adjustable Forehead Support Ball and Socket Clip Double-foam cushion Pressure pick-off port

Mask Fitting is Essential A full face mask surrounds the nose and mouth and rests below the lower lip Using a template can give an estimate of the appropriate mask size Courtesy of Respironics, Inc.

Fitting Full Face Mask Landmarks a)Below the lower lip with mouth open b)Corners of the mouth c)Just below the junction of nasal bone and cartilage 1 Courtesy of Respironics, Inc a b c b

Full Face Masks It should fit even if the patient’s mouth is slightly open Be sure the mask fits well and does not leak excessively, particularly not into the eyes

Minimizing Leaks Sometimes leaks are caused by the mask not being correctly seated on the face Some leaks can even be caused by excessive tension of the head straps. Minimize headgear tension (1-2 fingers should fit between head straps and face) In patients without a full set of teeth, using a full face or total face mask can help minimize leaks

Advantages and Disadvantages of Oronasal or Full Face Masks More effective for dyspneic patients Disadvantages: –Increased dead space –Difficulty in maintenance of adequate seal –Increased risk of facial pressure sores –Claustrophobia

More Disadvantages of Full Face Masks Increased risk of aspiration More difficulty with speech Inability to eat with mask in place More difficulty with secretion clearance Possible asphyxiation with ventilator malfunction

Nasal Pillows or Nasal Cushions Pillow Cushion Nasal Cushion Nasal Pillows to seal nares Respironics Comfort Lite  Nasal Mask

Nasal Pillows or Nasal Cushions (continued) Suitable for patients with –Claustrophobia –Skin sensitivities –Need for visibility Respironics Comfort Lite  Nasal Mask

Fitting Nasal Pillows or Nasal Cushions Using the plastic sizing gauge, insert each size into the nostril Choose the size that best seals the nostril Courtesy of Respironics, Inc.

Total Face Mask Interface selection –Total face mask –Mouthpiece Respironics Total  Face Mask

Mouthpiece/Lip Seal Mouth pieces with or without lip seals can also be used for an interface Their use is generally restricted to patients who are ventilator-dependent (chronic conditions) Some mouthpieces are used with nose clips Some patients use custom-made oral appliances for ventilation

Mask Selection Guide

NPPV- Masks With Leaks Vented masks require a vent for exhalation and use only one corrugated tube to connect to the ventilator Respironics BiPAP  Vision ® Noninvasive Ventilator with a Nasal Mask

NPPV – Masks Without Leaks Non-vented masks have both inspiratory and expiratory lines Exhaled volumes, flows and pressures can be monitored Respironics Esprit  Critical Care Ventilator with PerformaTrak  SE Full Face Mask

Tips on Initiating NPPV Ventilation Essential elements are staff competence and patient compliance Have a variety of masks available to ensure a proper fit. Change mask if the patient’s facial contours change, for example if facial edema develops

Tips on Initiating NPPV Ventilation, (continued) Let the patient breath through the mask before connecting the system in order to reduce anxiety (Perhaps allow the patient to hold the mask.) If the patient is claustrophobic, try a nasal mask (Make sure patient has their mouth closed or a chin strap may be needed) Courtesy of Respironics, Inc.

Tips on Initiating NPPV Ventilation, (continued) Place patient in an upright or sitting position Carefully explain the NPPV procedure to the patient including goals and potential complications

Example NPPV Settings Common IPAP orders –8 to 12 cm H 2 O –Adjust to change tidal volume Typical EPAP setting –4 cm H 2 O –Increase to improve oxygenation Respir Care 2004;49(1): IPAP = 12 EPAP = 4 PS = 8

Initial Ventilator Settings Progressively increase the pressure until the ordered pressures are achieved Then assess patient –Patient’s adaptability and comfort –Acceptable tidal volumes –SpO 2 and vital signs

Completing NPPV Setup Determine desired FIO 2 Set back-up rate Begin ventilation, coaching the patient until the patient becomes comfortable Monitor SpO 2 and adjust FIO 2 to maintain O 2 saturation > 90% Monitor HR and respiratory rate

Steps For Initiating NPPV Secure the mask to the patient –Avoid excessive tightening of the straps. Attach the interface to the ventilator (1-2 fingers space) Titrate IPAP, EPAP, inspiratory rise time, sensitivity (patient trigger), flow cycle, exhaled tidal volume, and synchrony with the ventilator

Steps For Initiating NPPV Avoid peak pressures > 20 to 25 cm H 2 0 Check for leaks and readjust the mask and head straps if necessary (It is essential to minimize leaks) Small leaks are compensated by most ventilators Allowing a small leak may avoid an excessively tight fit and possibly reduce the risk of skin breakdown

Monitoring the Leak Size 0-6 L/min=Mask may be too tight 7-25 L/min=Just right L/min=Adjust mask and monitor > 60 L/min=Caution Air Leak Guidelines for Vision  BiPAP  Noninvasive Ventilator Note: Leak compensation for noninvasive ventilation in critical care ventilators varies and could be as low as 20 L/min. Therefore, management of smaller leaks is required.

Predictors of Success with NPPV Positive initial response to NPPV within 1-2 hours –Correction of pH –Decreased respiratory rate –Reduced PaCO 2 Synchronous breathing efforts with ventilator Lower quantity of secretions Absence of pneumonia

Complications or Problems Associated with NPPV

Failure to Ventilate – Inadequate Volume Tidal volume is inadequate for patient Check ventilating pressures to be sure the Delta P is sufficient for the patient [DP = IPAP – EPAP or PS – PEEP] Be sure the rise time to pressure is sufficient Be sure the flow-cycle criteria is not too “short”, thus compromising volume delivery

Failure to Ventilate – Lack of Synchrony Patient and ventilator are not synchronous. Check the sensitivity. Is it easy for the patient to trigger a breath? Check the rise time to full pressure. Does it meet the patient’s flow demand? Check the flow-cycle criteria during PSV. Make sure it is set appropriate for the patient. (see section III of this teaching module)

Hypotension If hypotension was present prior to therapy, treat the cause If hypotension resulted after initiating NPPV, be sure ventilating pressures are not excessively high (peak pressures < 20 cm H 2 0)

Risk of Aspiration The risk of aspiration exists in some patients Maintain a policy of selecting patients appropriately for NPPV patients who can protect their own airway Examples of patients who may not be able to protect their airways: –Stroke victims, and individuals with a drug overdose. In these examples, an endotracheal tube should be inserted to protect the airway

Claustrophobia Try using a nasal interface or, Try using a total face mask, or Try mild sedation (use caution).

Gastric Insufflation (Aerophagia) and Gastric Distention Excessive pressure or air swallowing can cause air gastric inflation (insufflation) and gastric distention Use pressures less than 20 to 25 cm H 2 O Use simethicone (anti-flatulent) agent

Use of Nasogastric Tubes Use of nasogastric tubes to take air from the stomach is controversial The tube increases leaking around the mask The tube itself blocks a nasal passage Compression of tube against the skin by the mask may increase risk of skin breakdown

Possible Solution with Nasogastric Tubes If an NG tube must be used, one possible solution is to use an interface between the tube and the skin and mask Respironics NG Sealing Pad Image NG tube applied to groove Flat surface applied on patient’s face Mask interface across beveled side

Eye Irritation Eye irritation may result from air blowing in the eye Be sure mask fit is appropriate Spacers used on the forehead or the bridge of the nose, depending on the type of mask, may need to be adjusted Readjust headgear straps

Skin Problems Due to Interface Devices Skin irritation or rashes may occur due to pressure from a mask, frictional irritation between the skin and mask or due to allergies to the mask material Facial discomfort or pain can also occur

Possible Solutions to Skin Irritation Use the least amount of pressure to fit the mask that still prevents excessive leaks Use spacers Alternate devices to reduce skin breakdown Use a skin barrier lotion and/or topical corticosteroids

Skin Problems Due to Interface Devices Pressure lesions (skin breakdown, necrosis) if mask is to tight or left on for extended periods of time Use of Duodenum or Restore (skin dressings)

Poor Sleep Quality Inability to sleep well can be due to many causes such as anxiety, frequent disruptions of the patient at night during normal sleeping hours, discomfort caused by the mask or ventilating pressures Using an appropriate medication to reduce anxiety, and promote sleep may be appropriate Be sure the patient is able to protect their airway and is not likely to aspirate

Nasal or Oral Dryness, Nasal Congestion, Mucus Plugging When these problems occur, possible solutions include the following: –Add or increase humidification –Reduce leaks –Irrigate nasal passages with a saline spray

Nasal or Oral Dryness, Nasal Congestion, Mucus Plugging Use topical decongestants or steroids Perform oral and/or nasal hygiene If nasal mask is in use, use a chin strap to keep mouth closed or change to full face mask

Sinus or Ear Pain High inspiratory pressures may affect the ear and sinuses Use lower inspiratory pressure to help reduce ear and sinus pain Tight fitting masks may also put pressure on the nose and upper face and may affect sinus pressure and sinus drainage

Criteria for Termination of NPPV for Invasive Ventilation Worsening pH and PaCO 2 Tachynpnea (> 30 breaths/min) Hemodynamic instability SpO 2 < 90% Decreased level of consciousness Inability to clear secretions And inability to tolerate interfaces

Predictors of Success with NPPV Higher level of consciousness Younger age Lower severity of illness; no co-morbidities Less severe gas exchange (pH 7.10; PaCO 2 < 92 mm Hg) Minimal air leakage around the interface Dentition intact

Weaning If NPPV is successful, the patient may only require support for 2 to 3 days or less Currently there is no specific procedure for weaning from mechanical ventilation Trials of NPPV as tolerated

Weaning Algorithm Respir Care Vol. 49 (1):72-89 NO Continue with NPPV therapy Does patient meet weaning guidelines?  Clinically stable  RR < 24  HR < 110  pH > 7.35  SpO2 >90% on< 50% If patient status does not improved consider intubation NO YES Restart NPPV at previous settings YES Trial off NPPV with supplemental oxygen Slowly titrate IPAP downward in decrements of 2-3 cm H 2 O Does patient demonstrate clinical evidence of respiratory distress? Discontinue NPPV and place on supplemental oxygen

Section Summary This section has reviewed initiating NPPV, the interfaces used in NPPV, complications and problems along with possible solutions, and weaning from NPPV