Pre-Hospital CPAP What EMS should know Joe Holley, MD FACEP EMS Medical Director, State of Tennessee Member, ACEP EMS Committee

Objectives Review the goal & physiology of CPAP Discuss the indications and contraindications for CPAP use Review the literature supporting CPAP use Explore the role of CPAP use by pre-hospital providers Discuss the methods for implementing pre-hospital CPAP

PREHOSPITAL EMERGENCY CARE 2011;15:418 NIPPV is an important prehospital treatment modality for acute dyspnea. EMS agencies should select NIPPV systems and develop dyspnea care protocols suited to their patient populations, clinical capabilities, and receiving emergency department뭩 resources. EMS agencies must conduct quality assurance and inspection efforts to verify the safety and effectiveness of NIPPV. PREHOSPITAL EMERGENCY CARE 2011;15:418

Reduce the need for pre-hospital intubation! The Goal of CPAP? Reduce the need for pre-hospital intubation!

CPAP vs. Intubation CPAP Non-invasive Easily discontinued Easily adjusted Use by EMT-B Minimal complications Does not require sedation Comfortable Intubation Invasive Intubated stays intubated Requires highly trained personnel Significant complications Can require sedation or RSI Potential for infection Intensive Resource Utilization Impact on the System

The Problem Congestive Heart Failure Incidence 10 per 1000 patient (over age 65) transports 25% of Medicare Admissions Average LOS is 6.7 days 6.5 million hospital days Those who get intubated have significantly longer LOS 33% get intubated without non-invasive pressure support Intubated patients have 4 times the mortality of non-intubated patients

The Problem CHF/Pulmonary Edema Interstitial fluid interferes with gas exchange (ventilation and oxygenation) Increased myocardial workload resulting in higher oxygen demands (many of these patients are suffering ischemic heart disease) Traditional therapies designed to reduce pre-load and after-load as well as remove interstitial fluid

The Problem COPD/Asthma Increased work of breathing Hypercarbic (ventilation issue) Traditional therapies involve brochodilators which require adequate ventilation Higher mortality rate if intubated Difficult to wean once intubated Extremely difficult patient to intubate in the pre-hospital arena – usually requires RSI

Physiology of CPAP Airway pressure maintained at set level throughout inspiration and expiration Maintains patency of small airways and alveoli Improves gas exchange Improves delivery of bronchodilators Moves extracellular fluid into vasculature Reduces work of breathing

Supporting Literature JAMA December 28, 2005 “Noninvasive Ventilation in Acute Cardiogenic Edema”, Massip et. al. Meta-analysis of studies with good to excellent data 45% reduction in mortality 60% reduction in need to intubate

EFFECTIVENESS OF PREHOSPITAL CONTINUOUS POSITIVE AIRWAY PRESSURE IN THE MANAGEMENT OF ACUTE PULMONARY EDEMA Michael W. Hubble, PhD, NREMT-P, Michael E. Richards, MD, MPA, Roger Jarvis, EMT-P, Tori Millikan, EMT-P, Dwayne Young, BS, EMT-P PREHOSPITAL EMERGENCY CARE 2006;10:430–439 95 patients received standard therapy, and 120 patients received CPAP and standard therapy for Pulmonary Edema Intubation was required in 8.9% of CPAP-treated patients compared with 25.3% in the control group (p = 0.003), and mortality was lower in the CPAP group than in the control group When compared with the control group, the CPAP group had more improvement Patients receiving standard treatment were more likely to be intubated and more likely to die than those receiving standard therapy and CPAP.

Supporting Literature Reviews in Cardiovascular Medicine, vol. 3 supl. 4 2002, “Role of Noninvasive Ventilation in the Management of Acutely Decompensated Heart Failure” “Though BLPAP has theoretical advantages over CPAP, there are questions regarding its safety in a setting of CHF. The Key to success in using NIV to treat severe CHF is proper patient selection, close patient monitoring, proper application of the technology, and objective therapeutic goals. When used appropriately, NIV can be a useful adjunct in the treatment of a subset of patients with acute CHF at risk for endotracheal intubation.”

Supporting Literature Brochard (French abstract) “ Noninvasive ventilation for acute exacerbations of COPD” “…can reduce the need for intubation, LOS in hospital, and mortality rate”

Pre-hospital CPAP PEC 2000 NAEMSP Abstract, “Pre-hospital use of CPAP for presumed pulmonary edema: a preliminary case series”, Kosowsky, et. al. 19 patients Mean duration of therapy 15.5 minutes Oxygen sat. rose from 83.3% to 95.4% None were intubated in the field 2 intubated in the ED 5 subsequently intubated in hospital “Pre-hospital CPAP is feasible and may avert the need for intubation”

Types of Positive Pressure Ventilation 1) continuous positive airway pressure (CPAP) applies uniform supportive pressure during both inspiratory and expiratory phases. 2) bilevel positive airway pressure (BiPAP) is similar to CPAP but alternates different levels of inspiratory and expiratory pressure. Both CPAP and BiPAP systems typically provide pressure support of 4-10 cmH2O.

Is it Cost Effective? Hubble et al. evaluated the cost-effectiveness of prehospital CPAP in acute pulmonary edema. Using data from their 2006 publication, they predicted that four of every 1,000 EMS patients would require CPAP for acute pulmonary edema, resulting in 0.75 lives saved.

Is it Cost Effective? Accounting for the cost of CPAP equipment, including the cost of the CPAP-generating system, disposable mask, and tubing for each patient, training of personnel, and oxygen usage, the authors estimated that the cost-benefit of prehospital CPAP was $490 per life saved. They also predicted that CPAP would reduce hospitalization costs by $4,075 per year per application. Didn’t include the value of avoiding the ICU, Mechanical Ventilation, Complications, or availability of ICU bed for “the Next Patient”….potentially worth thousands of dollars

Delivery System Types External Pressure Regulated Turbulent Flow Virtual Valve

External Pressure Regulated Regulator-based portable NIPPV systems generate continuous pressure from oxygen flow, directly controlling inspiratory and expiratory pressure. Regulator-based NIPPV systems allow different inhaled oxygen fractions, reducing oxygen consumption. At 10 cmH2O pressure and 100% inspired oxygen (flowrate of 15 L/min), a size D oxygen cylinder will last between 20 and 30 minutes. At 65% inspired oxygen, a size D oxygen cylinder may last approximately 35 minutes. Regulator-based systems are often compatible with end-tidal capnometry and in-line medication nebulizers.

Disadvantages A disadvantage of regulator-based systems is their size; portable NIPPV regulators weigh approximately 3 pounds. Regulator-based systems are also expensive; the regulator costs $1,000-1,500, and each disposable hose circuit costs $25-50. Portable NIPPV systems may not be compatible with hospital wall oxygen outlets. During transition of care to the ED, EMS personnel may need to rely on portable oxygen tanks to maintain NIPPV operation until the availability of hospital NIPPV equipment.

Turbulent Flow Virtual valve. The Boussignac CPAP system uses a different NIPPV approach, accelerating oxygen flow through a series of channels to create turbulence. The turbulence acts as a virtual valve, generating positive airway pressure. The system is lightweight and disposable (single use) and uses a conventional oxygen source and flow regulator. Each disposable circuit costs approximately $70. On arrival at the ED, EMS personnel may transfer the system to hospital wall oxygen, thus minimizing care transfer delays.

Disadvantages A disadvantage of the Boussignac system is its limited maximum positive pressure of ~10 cmH2O with an oxygen flow of 25 L/min. Consequently, the system requires large quantities of oxygen. For a CPAP pressure of 5.0 cmH2O, a size D oxygen cylinder will last approximately 23 minutes. To generate a CPAP pressure of 10 cmH2O, a size D cylinder will last 14 minutes.

Transport Ventilators Select transport ventilators may be designed to provide BiPAP or CPAP. While dependent on the individual brand and model, the process involves placing the ventilator in pressure support mode, setting a desired inspiratory pressure support value, and setting a desired positive end-expiratory pressure (PEEP) value.

Indications for CPAP The general indication for NIPPV is dyspnea accompanied by early respiratory failure in patients with intact protective airway reflexes and mental status. CHF Pulmonary Edema Near Drowning Inhalation Exposure COPD Asthma Pneumonia

Possible Indications While utilized in in-hospital practice, the role of NIPPV for pneumonia-associated respiratory failure is less clear.

ContraIndications Patients with severe respiratory distress may not tolerate NIPPV. not suitable for patients with an absence of a gag reflex or altered mental status. not be able to cooperate with NIPPV increased risks of vomiting and aspiration consider ETI for these patients.

Use In Trauma? The utility in major trauma is unclear Invasive airway management of major trauma is difficult, and NIPPV may provide transient ventilatory support in these patients. However, potential NIPPV pitfalls in the setting of trauma include the risk of pneumocephalus, subcutaneous emphysema or bacterial meningitis in patients with midface fractures, pneumothorax in thoracic trauma, and increased intrathoracic pressure causing hypotension

Generally Accepted ContraIndications Patient less than eight years of age (Fitment Issues) Unable to maintain a patent airway Decreased level of consciousness (LOC) Pneumothorax Facial trauma/burns Systolic BP < 90 mmHg Recent surgery to face or mouth Epistaxis Patient unable to tolerate mask or pressure Pneumonia (relative contraindication)

What about the Hypoxic Drive Issue? Certainly this physiologic phenomenon exists, it is relatively uncommon and many hypoxic COPD patients have been denied much needed oxygen out of fear of causing worse hypercapnia. As a result, left ventricular function suffers as does renal, mental and other related issues. Moreover, when this phenomenon does occur, it is in the setting of non-pressurized oxygen delivery (read nasal cannula or face masks) and not with CPAP, BiPAP or intubation and placement of the patient on mechanical artificial ventilation. All three of these modalities resolve hypercapnia by increasing alveolar ventilation. Recall that as alveolar ventilation goes up, PaCO2 goes down and respiratory acidosis lessens. The COPD patient with known hypercapnia should never be transported to the ED on non-pressurized oxygen. However, hypoxic COPD patients can be safely transported with supplemental oxygen driven by CPAP.

Intubation Patients who cannot cooperate, maintain their own airway, or have adequate respiratory effort are not candidates for CPAP. They require immediate intubation. Monitor your patient for a failure to respond to CPAP, as noted by a declining mental status or ability to comply with CPAP. Not all patients will respond, and may require intubation. Patients who have intractable vomiting may not be able to protect their airway, and need intubation.

Training Key elements of training should cover: Pathophysiology of acute dyspnea Physiology of NIPPV systems Description of CPAP and BiPAP mechanics, with focus on the systems available to the individual EMS agency Indications and contraindications for NIPPV Initiation and titration of NIPPV therapy Titration of concurrent pharmacologic therapy Management of adverse events Transition of care at the receiving hospital Alternate care strategies

Training The technique of NIPPV application will vary with the employed system. Application of the face mask must ensure a tight seal. Facial hair may require trimming to achieve a tight seal. An adequate mask seal may not be possible with edentulous patients or individuals with facial abnormalities. Patient Coaching is very important to successful application

Application in the Field Continuous positive airway pressure systems have single pressure setting for both inspiration and expiration. A typical initial setting is 5 cmH2O, with pressure adjustments every few minutes in response to the patient’s subjective and objective work of breathing, respiratory rate, and oxygen saturation. The typical range of pressure settings is 5-10 cmH2O. Bilevel positive airway pressure is similar to CPAP, but alternates a higher inspiratory pressure with a lower expiratory pressure. Typical initial settings include an inspiratory pressure of 10 cmH2O and an expiratory pressure of 5 cmH2O, with subsequent adjustments according to patient response.

Medication Administration Many CPAP devices allow for the concurrent administration of nebulized medications. Medications are generally more effective due to improved recruitment, airway patency, and pressure support. Indications for Bronchodilators are the same regardless of the use of CPAP

Patient Monitoring Respiratory rate: A reduction in respiratory rate (and effort) may indicate clinical response to NIPPV. Heart rate: Improvement in ventilation and perfusion with NIPPV may reduce the heart rate. However, the heart rate may also increase in response to increased intrathoracic pressure and decreased venous return. Systolic blood pressure: The increase in intrathoracic pressure from NIPPV may decrease venous return to the heart, leading to a decrease in blood pressure. The development of hypotension (systolic blood pressure <100 mmHg) or hypoperfusion (cyanosis, decreased capillary refill) may indicate the need for reduced NIPPV support. Oxygen saturation: Oxygen saturation may improve with application of NIPPV. End-tidal capnography: End-tidal carbon dioxide (ETCO2) monitoring to gauge NIPPV response. Upon initial application of NIPPV, ETCO2 may increase from improvement in ventilatio/perfusion mismatch. Decreasing ETCO2 may reflect respiratory improvement from NIPPV. Subjective dyspnea ratings of patient subjective dyspnea, auscultation intensity, cyanosis, and accessory respiratory muscle use.

Wisconsin EMT–Basic Experience Question: Can EMT-Basics apply CPAP as safely as Paramedics? 50 EMT-Basic services 2 hour didactic, 2 hour lab, written and practical test Required data collection Compared to same data collected by ALS services during same period

Wisconsin EMT–Basic Experience Required data collection Criteria used to apply CPAP Absence of contraindications Q 5 min. vital signs including oxygen sats. Subjective dyspnea score Because EMT–Basics don’t diagnose a unique “Respiratory Distress” protocol used to capture patients

Adult Respiratory Distress Protocol (Age greater than 12) Routine Medical Assessment Oxygen 2 LPM via Nasal Cannula Titrate to maintain Pulse ox of >92% Is Patient a candidate for Mask CPAP? Respiratory Rate > 25 / min Retractions or accessory muscle use Pulse ox < 94% at any time Yes See Mask CPAP Protocol No Is the Patient wheezing and/or does the Patient have a history of Asthma/COPD? Yes Administer Albuterol / Atrovent by Nebulizer Step through the protocol. Emphasize the need for medical care regardless of whether or not the patient is a CPAP candidate No Does the Patient have rales and/or does the Patient have a history of congestive heart failure (CHF)? If Basic IV Tech: Administer 1 spray sublingual NTG every 5 minutes as long as systolic BP is greater than 100mmHg Yes No Contact Medical Control Consider ALS Intercept and Transport

Mask CPAP for EMT-Basic Asses Patient, record vital signs and pulse ox before applying oxygen CPAP Inclusion Criteria (2 or more of the following) Retractions or Accessory muscle use Respiratory Rate > 25 / minutes Pulse Ox < 94% at any time CPAP Exclusion Criteria -Unable to follow commands Apnea Vomiting or active GI bleed Major trauma / pneumothorax Conditions Indicated for CPAP Congestive Heart Failure COPD / Asthma Pneumonia Does the Patient meet two or more Inclusion Criteria? No Yes Yes Does the Patient meet any Exclusion Criteria? Continue standard BLS Respiratory Distress Protocol No Administer CPAP 5 cm H2O of pressure AND Reassess patient, vital signs, and respiratory distress scale every 5 min. Step through the CPAP protocol Stress the need for frequent vital signs and patient assessment Patient condition is deteriorating Decreasing LOC Decreasing Pulse Ox Notify Medical Control Consider ALS Intercept and continue BLS Respiratory Distress Protocol Patient condition is stable or improving Notify Medical Control Continue CPAP Reassess patient every 5 minutes Remove CPAP Apply BVM Ventilation

Wisconsin EMT-Basic Experience Results (preliminary – study completed 11/05) 500 applications of CPAP (114 services) 99% met criteria for CPAP on review of medical director No field intubations by those services with ALS intercepts No significant complications All oxygen sats. improved, dyspnea reduced by average of 50%

Wisconsin EMT – Basic Experience State approved CPAP for EMT-Basic scope of practice 2/06 Questions yet to be answered What conditions did the patients have? Was it applied too liberally? Key Point Services without ALS intercept did just as well as those with it

Implementation in Your System How good is current care for respiratory distress? Aggressive nitrates for CHF? Aggressive use of bronchodilators? Pre-hospital and hospital intubation rate? Requires active medical oversight Airway management is a sentinel event ALS or BLS or BOTH?

Items to Consider Equipment Must be easy to use and portable Adjustable to patient’s need Easily started and discontinued Provide quantifiable and reliable airway pressures Conservative oxygen utilization Not interfere with administration traditional therapies for underlying condition

Items to Consider Oxygen concentration Fixed versus Variable rates Fixed rates are either 35% or 100% in current models but actual concentration will be less depending on leaks and minute ventilation Variable rate increases chance of inadequate oxygen supply Pressure level Most studies show 5cm H20 sufficient Complication rate goes up with pressure

Summary CPAP is a non-invasive procedure that is easily applied and can be easily discontinued without untoward patient discomfort CPAP is an established therapeutic modality Data supports its use in CHF, pulmonary edema, COPD/Asthma, and pneumonia

The Future NAEMSP is a strong supporter of CPAP in the field The Data is very solid supporting its use Safety Cost effectiveness Its SIMPLY the RIGHT THING for OUR Patients!!

What’s the holdup? Yet to be recognized by payors as a separate billable service. Medicare currently will only pay if its used in conjunction with Endotracheal Intubation!! What’s the Point!!!! Hospitals have been slow to adopt Efficiencies Improve if adopted on a system wide basis

Questions? Joe Holley, MD FACEP