BLS: CLINICAL PEARLS
Public access defibrillators (PADs) are intended to reduce the time to defibrillation for cardiac arrest victims. In most cases, the AEDs are mounted in a protective box, similar to a fire extinguisher. While anyone can access the AED, in most cases certain personnel working in the building (i.e. security officers) have received CPR and AED training and are designated to respond when an emergency occurs.
Laws regarding the use of public access defibrillators do vary from state to state. Most, but not all, states provide for civil immunity even for untrained rescuers provided they “acted in good faith”. Some states require prior training in CPR and AED use, which you are obtaining through this course!
As a potential rescuer trained in CPR, if you find a cardiac arrest victim and a public access defibrillator is available, bring it to the victim. Follow the CPR guidelines to use the AED, if needed. Know your local / state laws related to public access defibrillators, and cooperate with local responders as they arrive!
The old “A-B-C” sequence was certainly easy to learn and remember; however, the sequence change to start with chest compressions was made for several important reasons:
- Researchers found many rescuers got stuck on the “A” or “B”, delaying chest compressions! Successfully opening the airway and delivering rescue breaths is a challenging skill, especially for rescuers that do not use these skills regularly. When rescuers were unsuccessful with rescue breathing, multiple attempts at opening the airway or giving breaths would sometimes result in long delays before chest compressions were first started.
- Many lay rescuers are hesitant to perform rescue breathing without a barrier device. This can actually prevent some rescuers from starting CPR at all – significantly decreasing the victim’s chance of survival. By starting with chest compressions, the barriers to action are reduced.
- For a victim that collapses suddenly, we were leaving the best for last! For a victim of sudden cardiac arrest, the victim is likely still taking some occasional gasping breaths, and there is still oxygenated blood – it’s just not moving! For these victims, chest compressions are the most important step of CPR, and early chest compressions will greatly increase the chance of survival (and the chance of successful defibrillation when an AED arrives)!
The new C-A-B sequence reduces the time to chest compressions, increases the likelihood that lay rescuers are willing to act, and increases the chance of survival from cardiac arrest.
That is correct, the new CPR guidelines de-emphasize the pulse check prior to starting CPR, even for trained healthcare providers. Healthcare providers still have the option of checking for a pulse, but for no longer than 10 seconds. There are a couple reasons for this change, but they all relate to reducing delays in starting CPR.
Feeling a pulse is relatively easy when practicing on a fellow student or co-worker… we already know they have a pulse! The pulse check is a much more difficult skill when confronted with an unresponsive victim. Even trained healthcare providers may struggle with the pulse check and either take too long or even get the wrong answer! Research studies have found that both trained and untrained rescuers will not accurately determine whether a pulse is (or is not) present 100% of the time.
The consequence of a “false positive” (thinking a pulse is felt, when in fact the patient is pulseless) is potentially fatal – the patient will not receive CPR when it is needed! To minimize this risk, and ensure that all patients that need CPR will get CPR, the current guidelines emphasize checking for responsiveness and looking for normal breathing – a victim that does not respond and has no normal breathing is most likely pulseless, start CPR immediately!
You should always assess your patient before beginning CPR. However, the current guidelines suggest that checking for responsiveness (tapping the victim and shouting to him/her) and looking for normal breathing are much better tools than the pulse check in an emergency situation.
There is a small chance that by using these guidelines you could begin CPR on a patient with a pulse. There are risks associated with CPR, including broken ribs and other injuries. However, the potential benefits of providing CPR to all patients in cardiac arrest far outweigh the risks from these less common scenarios.
If you do not get a response or see normal breathing (or feel a pulse for healthcare providers) within 10 seconds, or if you are uncertain, begin CPR starting with chest compressions.
Yes, but not normal breathing. The patient in cardiac arrest will not breathe at a normal rate. However, in the first minutes after cardiac arrest occurs, many patients will still take occasional gasping breaths. These occasional breaths will be irregular and slow (only a few times per minute), and should be easy to distinguish from regular breathing. These occasional gasping breaths are not normal breathing and are often referred to as agonal breathing. If you see agonal breathing, do not stop or withhold CPR!
Maybe! Most hospitals and other large healthcare settings have established emergency response numbers to activate the facility’s emergency response team (“Code Team”). Dialing the established emergency response number will get help to you faster than calling 9-1-1 in these situations because these large facilities have an internal emergency response team.
If you are working in a healthcare facility, find out what number to dial in an emergency. If you are a visitor, find an employee and direct them to call for help – if alone, follow the directions posted on the phone, or dial 9-1-1.
Leaving to call for help right away and retrieve an AED (if you are alone) decreases the time to defibrillation by getting an AED or manual defibrillator to the victim faster. For the adult victim, defibrillation combined with effective CPR is the most likely intervention to successfully resuscitate the victim. Defibrillation success rates and survival rates decrease over time. The sooner the AED or manual defibrillator arrives and can be applied to the patient, the greater the chance that he/she will survive.
Infants and children have a different set of common causes of cardiac arrest than adults. While adult cardiac arrest is most often caused by a lethal cardiac arrhythmia or other heart problem, cardiac arrest in infants and children is more commonly caused by an airway or breathing problem. For this reason, providing two minutes of CPR before leaving to call for help (if you are alone) may be beneficial for pediatric patients. CPR alone may correct the problem, or prevent the pediatric patient that is near-arrest (respiratory arrest, etc.) from getting worse. If there is no improvement after two minutes of CPR, then an AED is likely needed and you should leave to call for help and retrieve an AED (if available).
Providing excellent chest compressions is critical to patient survival, and it is also exhausting!
Chest compression effectiveness will begin to decrease (i.e. shallow compressions, slow compression rate, or incomplete recoil) before the rescuer senses that he/she is becoming fatigued. To avoid rescuer fatigue and maximize the effectiveness of chest compressions, the chest compressor should be rotated every two minutes when two or more rescuers are present.
Yes, there is some risk associated with moving the neck of an injured victim. However, this risk is relatively small and priority should be given to successful resuscitation. Avoid excessive or unnecessary movement of the patient’s head and neck while still providing effective CPR.
For trained healthcare providers, the jaw-thrust technique can be used to open the airway when injury is suspected. For the cardiac arrest victim, opening the airway and delivering rescue breaths successfully is essential to patient survival. If the jaw thrust technique is unsuccessful, the “head-tilt, chin-lift” should be used – even if injury is suspected.
This is a common question, as the volume of air delivered will vary for every patient. There is no specific number to remember regarding the volume of air to be delivered. Instead, watch the patient’s chest as you deliver breaths. Each rescue breath should be delivered with just enough air to make the chest visibly rise.
Resuscitation equipment, such as the bag-valve-mask (BVM), is available in various sizes. Choose the correct size for the patient (i.e. infant, child, adult). However, you do not need to deliver the full volume of air with each breath. With a BVM device, squeeze the bag just enough to see chest rise, then stop – this only requires a partial squeeze for most patients.
If injury is suspected, keep the patient on their back and avoid unnecessary movements, especially of the head or neck. If the patient is still unconscious, it may be necessary for you to manually keep their airway open until help arrives. Frequently re-assess their breathing and circulation.
For the uninjured victim, you may place the patient in the “recovery position.” Roll the patient onto either side, and place the arm or a supporting object underneath the head to keep it in line with the body. The recovery position allows you to see the victim to monitor breathing and circulation. Positioning the victim on their side also helps keep the airway open – the tongue falls to the side and excess secretions can drain away from the airway.
The current guidelines acknowledge that some rescuers may be unable or unwilling to perform rescue breaths without a barrier device. If you are confronted with this situation outside of work, you should assess the victim, call or send for help, and begin the C-A-B sequence. If you cannot deliver rescue breaths, continue with uninterrupted chest compressions. Chest compressions alone (“Hands-only CPR”) is still effective and is commonly used by emergency medical dispatchers to instruct untrained rescuers. If a barrier device arrives, or another rescuer is willing to deliver rescue breaths, then resume standard CPR.
We cannot say that you cannot be sued, simply because anyone can file a lawsuit for almost any reason (and because we are not lawyers)! However, the actions described above are included in the current CPR guidelines for just the situation you are asking about. In addition, most states have “good Samaritan” laws designed to protect rescuers when they are helping outside of a work setting, provided that they are “acting in good faith” – these laws are meant to encourage the public to help without fear of frivolous litigation.
If you find yourself in this situation, you may act with confidence that you are helping the victim and following the current CPR guidelines!
The bag-valve-mask (BVM) is the most commonly used device for rescue breathing in a healthcare setting. However, this is device may be difficult to use without two rescuers. The preferred method is for one rescuer to hold the mask on the patient’s face and maintain the airway, while a second rescuer squeezes the bag to deliver breaths.
Maintaining an adequate mask seal with one hand is difficult for most rescuers, so lone rescuers should consider using other barrier devices until additional help arrives. This is especially true if you are a lone rescuer providing CPR – re-establishing a mask seal with the BVM between sets of chest compressions can delay CPR.
Yes, it is slower than normal and that is okay!
During CPR, chest compressions are most effective when the pressure inside the chest is kept to a minimum. Excessive ventilation increases this pressure (intrathoracic pressure) and can reduce the amount of blood returning to the heart between compressions. A slow rescue breathing rate reduces this pressure and maximizes circulation. The slower rate delivered through an advanced airway, using 100% oxygen, is still adequate to maintain oxygenation during cardiac arrest.
Keep in mind that a faster rescue breathing rate, 1 breath every 5 – 6 seconds for an adult, or 1 breath every 3 – 5 seconds for an infant/child, should be used if spontaneous circulation returns.
No. The AED should only be applied if a patient is unresponsive with no normal breathing.
The AED cannot determine if the patient has a pulse or not, it only “sees” the heart’s electrical rhythm. If a patient has an abnormal heart rhythm, but is not in cardiac arrest (the patient is responsive and breathing), the AED could potentially deliver an unnecessary defibrillation which may make the patient’s condition worse – it could even cause cardiac arrest. If you suspect someone is having a heart attack, call 9-1-1, keep the patient calm, and continue to re-assess their breathing and circulation until help arrives. If the victim becomes unresponsive with no normal breathing, then start CPR and apply the AED.
Absolutely! With multiple rescuers, continue CPR while one rescuer applies the AED. You can continue chest compressions until the AED prompts you to “Stand Clear”. The shorter the time between the last chest compression and defibrillation, the greater the chance of successful defibrillation.
Chest compressions may resume as soon as the shock is delivered. If you are using an AED, listen for the AED to give an audible prompt that the shock was successfully delivered (i.e. “Shock Delivered”).
Do not stop to re-assess the patient or check a pulse prior to resuming CPR!
Child CPR should be used for victims from 1 year of age to the onset of puberty. For the CPR guidelines, onset of puberty is defined as the presence of axillary hair for the male patient, or breast development for the female patient. The differences between adult and child CPR are most important for younger children – if you are unsure of the victim’s age, do not delay starting CPR!
Also, remember that chest compressions for the child may be performed with either one or two hands depending on the size of the child.
No, it does not. If the AED prompts say “No Shock Advised,” this only means the AED has not identified a heart rhythm that it can fix with defibrillation (ventricular fibrillation or ventricular tachycardia).
Current AED technology cannot sense whether or not the patient has a pulse.
You will receive the same message (“No Shock Advised”) for the patient in a normal heart rhythm with a pulse as you would for the patient with no electrical activity (asystole / flat line) without a pulse. It is up to you as the rescuer to continue CPR until the patient responds or other rescuers take over.
No, the AED should be left in place – do not turn off the AED!
A “No Shock Advised” message indicates that the AED does not sense a heart rhythm that can be corrected by defibrillation. However, the heart rhythm may change as resuscitation continues. The AED will continue to re-assess the patient’s heart rhythm every two minutes, and if a shockable rhythm develops (ventricular fibrillation or ventricular tachycardia), the AED will prompt you to defibrillate.
When a lone rescuer is present, a 30:2 ratio is recommended for all age groups – infant, child, and adult. This ratio allows for ease of learning CPR, and is considered the best balance of compressions and breaths when only one rescuer is present.
When multiple rescuers are present, a 15:2 ratio is recommended for infants and children because they typically require more frequent breaths, and are more likely to be in cardiac arrest as a result of an airway or breathing problem. Adults are less likely to be in cardiac arrest because of an airway or breathing problem, and are thought to benefit more from longer sets of chest compressions with fewer interruptions.
The ratios in the CPR guidelines reflect the current consensus of resuscitation experts, and research regarding the ideal CPR ratios for each age group continues.
When a choking victim is able to speak or cough forcefully, this indicates that there is likely a partial airway obstruction. This is a potentially life-threatening situation, and you should still call for help. However, trying to dislodge the object (delivering abdominal thrusts for the child or adult, or delivering back blows and chest thrusts for the infant) could make the situation worse. The victim is still getting some air in and out as they breathe — efforts to dislodge the obstruction could instead cause it to move and completely block the airway, resulting in no breathing at all.