Overview of EMS Prehospital CPAP Devices
Noninvasive ventilation is a method where support for breathing is provided through a mask or a similar device worn over your upper airway – this technique eliminates the need for a tube to be put down your throat, a procedure known as endotracheal intubation. This approach prevents complications such as ventilator-associated pneumonia, a lung infection that can occur in people who are on breathing machines in hospitals, and trauma to the airway that can occur with invasive procedures.
The specific type of noninvasive ventilation, known as noninvasive positive pressure ventilation (NIPPV), has become an essential treatment method for respiratory distress when outside the hospital. The concept behind NIPPV started during the 1950s polio outbreak, by a man named Bjorn Ibsen, who greatly reduced death rates with this technique. By the 1980s, noninvasive variations of continuous positive airway pressure (CPAP), another type of noninvasive ventilation, were being used for conditions like sleep apnea and chronic obstructive pulmonary disease (COPD), a type of lung disease.
Early versions of NIPPV used a control unit linked to the oxygen source to generate the necessary positive pressure to assist breathing. Modern CPAP devices can deliver a specific level of pressure by adjusting a control valve or the flow of oxygen, which creates the necessary positive pressure at the end of your exhale (PEEP). These new devices are integrated, cheaper, and easier to use than the original models.
Starting from the late 1990s, using CPAP outside of a hospital has grown popular as a primary method of NIPPV and an alternative to endotracheal intubation or supraglottic devices – these are tools often used to keep your airway open. CPAP is now the most widely used type of NIPPV, and helps decrease the effort it takes to breathe and the amount of oxygen reaching your body for people with varying heart and lung conditions. Using NIPPV outside a hospital environment reduces the need for intubation and lessens complications like low blood pressure, low levels of oxygen in your blood, and cardiac arrest. Over the past few years, this type of breathing support has become a normal part of care for patients with serious difficulty breathing when outside the hospital. Recent studies by Goodacre and others have shown a drop in death rates and intubation rates when using this method compared to standard care.
Anatomy and Physiology of EMS Prehospital CPAP Devices
NIPPV, or non-invasive positive pressure ventilation, is a breathing technique that helps improve the functioning of the lungs. By improving the flexibility of your lungs (lung compliance), it enables your lungs to hold more air, and it also reduces the amount of work your lungs have to do to breathe. This process requires something known as PEEP (positive end-expiratory pressure) and IPAP (inspiratory positive airway pressure).
PEEP is extremely beneficial for people with conditions such as COPD (chronic obstructive pulmonary disease), as it helps to keep the tiny sacs in your lungs (alveoli) open to allow for more efficient exchange of oxygen and carbon dioxide. Normally, during the end of a breath, these sacs can collapse within the lungs due to a negative pressure environment created by your breathing. But in people who suffer from COPD or lung fibrosis, these sacs have trouble collapsing completely due to trapped air. Thus, applying PEEP helps to overcome this issue.
Another method used is applying a constant pressure called CPAP (continuous positive airway pressure) during your breathing cycle. This process prevents the tiny sacs in your lungs from collapsing completely when you breathe out, thus further improving the air exchange.
This technique also tackles other issues, such as improving the exchange of gases and reducing fluid accumulation (edema) in the lungs. By increasing the pressure inside the chest (intrathoracic pressure), the work of breathing is reduced. Making the tiny sacs in the lungs cover more area also helps to improve its efficiency. Lastly, the increased pressure inside the chest reduces the amount of blood return to the heart and encourages the extra fluid in the lungs to move back into the bloodstream, reducing fluid buildup.
Why do People Need EMS Prehospital CPAP Devices
If you’re a person who breathes normally and your lungs work fine, you might be able to benefit from Non-invasive positive pressure ventilation (NIPPV). NIPPV uses a little pressure to help your lungs work better. It helps to open up small spaces in your lungs that might have collapsed and balance out your breathing. It’s a bit like inflating a balloon to make it work better. A specific type of NIPPV is Continuous Positive Airway Pressure or CPAP, which makes your heart work better and can help decrease fluid buildup in your lungs.
CPAP is most often used when people have certain health conditions. Some examples include:
- Heart failure: NIPPV helps lessen the need for putting tubes in to help breathing in patients who are experiencing an acute or sudden episode of heart failure that is causing fluid buildup in the lungs. This works by decreasing the pressure in the heart.
- Long-term lung diseases, including COPD and asthma: Another type of NIPPV, called Bilevel positive airway pressure (BiPAP), helps to reduce the energy needed to breathe and improves the exchange of gases in the lungs. This can prevent the worsening of respiratory failure. NIPPV can also help in severe asthma attacks by reducing the amount of air trapped in the lungs and improving lung function.
- Acute bronchitis and pneumonia: In some cases, NIPPV can also help patients with lung infections like pneumonia. It does this by improving the amount of oxygen in your blood and reducing the energy needed to breathe, especially in those with chronic lung disease.
Noninvasive positive pressure ventilation can also be useful in many other situations. It can be used with people who have had chest injuries that make it hard to breathe, people who have inhaled something harmful like chlorine, in people who have severe obesity, following near drownings, in newborn babies with breathing difficulties, and in patients who have chosen not to use intensive life-saving treatments due to an advanced disease or terminal illness.
When a Person Should Avoid EMS Prehospital CPAP Devices
Non-invasive positive pressure ventilation (NIPPV) is a type of breathing support that includes methods like using a mask over the nose and mouth instead of a tube inserted directly into the windpipe. However, there are certain conditions in which using NIPPV is not recommended.
For instance, when a person’s heart or breathing has stopped, when they are in a coma or any state that requires a quick insertion of a tube into the windpipe (immediate intubation), NIPPV should not be used. Similarly, if the person has face burns or injuries, or is actively vomiting or has a blocked airway, NIPPV may not be an appropriate choice of treatment.
There are also some conditions in which using NIPPV might be possible but should be carefully considered. These include:
• People unable to clear secretions (substances that are produced and need to be expelled from the body, like mucus) from their airway on their own
• Those who are feeling lethargic and having trouble with sensing their surroundings
• Individuals in shock and need medicine to maintain blood pressure (pressor support)
• Cases with irregular heart rhythms (ventricular dysrhythmias)
• Circumstances when a person can’t stop vomiting (intractable emesis)
• Conditions with uncontrollable bleeding
• A severe seizure condition known as status epilepticus
• Potential blockage of the upper airway
• Severe allergic reaction (Anaphylaxis)
• Injuries to the trachea (the tube that carries air to your lungs)
• Facial or skull fractures, often affecting the jaw (maxillofacial) or base of the skull (basilar)
• External growths that are putting pressure on the airway.
Equipment used for EMS Prehospital CPAP Devices
Today, modern Continuous Positive Airway Pressure (CPAP) machines, small devices used for sleep apnea treatment, are both readily portable and cost-effective. They include a flow generator and a special valve, known as a PEEP valve, to keep a steady level of air pressure. For emergency medical staff out in the field, there are many high-quality devices available that combine the flow generator with a one-use face mask.
The usual settings on these machines usually vary between 5 to 10 cm H2O (a measure of pressure). Patients with conditions like asthma, bronchitis, and COPD (Chronic Obstructive Pulmonary Disease), which affect breathing, usually start with a pressure setting of 5 cm H2O. On the other hand, those with heart failure, severe pneumonia, or lung fluid due to nearly drowning typically begin with a higher setting of 10 cm H2O.
In both cases, these machines can make a big difference. Working at these settings, they can reduce the effort of breathing by up to 60%. They can also increase endurance of the muscles used for breathing by up to 95%. In other words, they help make breathing easier and more efficient for patients with these conditions.
Who is needed to perform EMS Prehospital CPAP Devices?
Non-invasive positive pressure ventilation (NIPPV) is a type of breathing support that can be administered in case of an emergency, and it require well-trained emergency medical service (EMS) personnel. EMS personnel include Emergency Medical Technicians (EMTs) and paramedics. These emergency healthcare professionals need to know how to choose the right patients for this procedure, how to fit a mask correctly, and how to effectively keep an eye on how the patient is responding to the therapy.
Over time, the job responsibilities of EMS clinicians have expanded. In 2018, The National Highway Traffic Safety Administration introduced a guideline that redefined the tasks prehospital clinicians are expected to perform. Initially, according to the 2007 model, only paramedics were trained to use machines like CPAP (Continuous Positive Airway Pressure) and BiPAP (Bilevel Positive Airway Pressure), which are used to assist breathing. But the update in 2018 means that now EMT-Basics are also trained to use the CPAP machine while treating patients. In many areas, an EMT-B (a type of emergency medical technician) can use a CPAP device, as long as they have been suitably trained and given the go-ahead from their medical director.
Emergency medical staff should receive training in when and when not to use NIPPV (indications and contraindications), as well as how to apply it practically. They should also be able to troubleshoot common issues. Guidelines should make clear the specific conditions for starting non-invasive ventilation, how to monitor the treatment’s effectiveness, and the steps to take if NIPPV isn’t working as well as expected.
Preparing for EMS Prehospital CPAP Devices
Patients who are new to using an NIPPV device, a type of breathing machine, need to be taught how to use it before it is applied. This training is necessary to ensure they do not resist or struggle with the device. Some patients may experience claustrophobia, or fear of tight spaces, when using a full-face mask. Therefore, it’s crucial for doctors and other health workers to educate and guide these patients to ensure their comfort.
When a patient has severe difficulty breathing, the clinicians at the scene should assemble the NIPPV device quickly. The device must be properly connected to an oxygen source that is filled well because these devices typically use a lot of oxygen for working correctly. Guidelines provided by the device’s manufacturers should always be followed for correct use.
How is EMS Prehospital CPAP Devices performed
Before a doctor puts a CPAP mask on a patient, they explain to the patient how the mask will feel. This is to help the patient know what to expect and reduce any worries about wearing the device. The mask is then placed onto the patient’s face and they’re guided to take deep breaths. The doctor has to make sure that the mask isn’t too tight because this can cause discomfort and the mask could leak air. The mask is kept comfortably in place with a head strap. The patient is made to sit in a slightly raised position to help them breathe better.
The CPAP machine, a device that helps with breathing, is started with a lower pressure setting of about 5 cm H2O (a unit for measuring pressure) so that the patient can get used to it. Over time, this pressure can be increased to a maximum of 10 cm H2O. Some people might need a higher pressure. Also, the amount of oxygen given from the device can be adjusted based on the patient’s SpO2 reading (this tells us how much oxygen is in the blood) – usually starting with 2 to 4 liters per minute.
The BiPAP machine is another type of device that helps people with their breathing. This machine starts at lower pressures too so the patient can adjust. This typically means an IPAP (this is the pressure applied when you breathe in) of 10 cm H2O and an expiratory positive airway pressure (pressure applied when you breathe out) of 5 cm H2O. IPAP is typically set between 10 to 20 cm H2O, and expiratory positive airway pressure is usually from 4 to 10 cm H2O. The flow of oxygen from the BiPAP machine begins at 2 to 4 liters per minute and can be changed according to the patient’s SpO2 readings.
Doctors will regularly check up on a patient’s condition to optimize their breathing, by checking how the lungs sound and how the patient is adjusting to the machine. The patient’s vital signs, which include breathing rate, heart rate, blood pressure, and SpO2, are continuously monitored. The improvement in the patient, such as feeling less out of breath, a slower breathing rate, and steady vital signs, tells the doctor how the patient is responding to the machine.
Possible Complications of EMS Prehospital CPAP Devices
Using a non-invasive positive pressure ventilation (NIPPV) machine, which helps with breathing, can sometimes cause discomfort, anxiety, and restlessness in patients. More serious problems can include lung damage, or abnormally low blood pressure. This low blood pressure can happen because the machine increases pressure inside the chest and reduces the amount of blood returning to the heart.
Some patients might experience bloating, which leads to a condition called abdominal compartment syndrome, especially if the pressure applied by the NIPPV machine is too high. Yet, many of these issues can be managed by adjusting the machine to the lowest possible setting that still helps with breathing. If a patient has low blood pressure, this can be treated with intravenous fluids, which are given through a drip into a vein.
What Else Should I Know About EMS Prehospital CPAP Devices?
Using non-invasive methods like positive pressure and CPAP ventilation can greatly help in relieving acute breathing problems caused by various factors. Non-Invasive Positive Pressure Ventilation (NIPPV), reduces the need for intubation and other invasive treatments that could lead to additional problems like infections, prolonged hospital stays, and even aspiration (inhalation of food, stomach acid, or saliva into the lungs).
This treatment is especially helpful for heart failure and Chronic Obstructive Pulmonary Disease (COPD) patients. According to a study by Ucgun and colleagues, the main predictor of fatality in COPD patients is invasive ventilation and its related complications. So, it’s crucial to avoid invasive ventilation wherever possible.
Recent studies and data analyses have shown that using NIPPV treatment outside the hospital (i.e., prehospital) significantly improves the patient’s health outcomes. Specifically, it has been revealed that NIPPV can cut down mortality rates and lessen the need for intubation.
NIPPV, including CPAP (Continuous Positive Airway Pressure) and BiPAP (Bilevel Positive Airway Pressure), is a vital step in managing prehospital respiratory distress. Its usage is strongly recommended in conditions like heart failure, COPD, and possibly asthma and pneumonia. It requires the right training, suitable equipment, and clearly outlined protocols to be implemented efficiently. By incorporating NIPPV into the treatment process, the patient’s health outcome can be enhanced significantly, and it can also alleviate the workload of emergency departments as ambulance services continue to evolve.