WHAT DOES MANUAL DEFIBRILLATOR MEAN?

If you’re trained in first aid or expected to use an AED, you may come across the term “manual defibrillator.” But what does it mean, and how does it differ from an automated external defibrillator (AED)? Knowing what a manual defibrillator is and how it operates can enable you to provide the most effective care to individuals who experience sudden cardiac arrest.

How Does a Manual Defibrillator Work?

A manual defibrillator has the same goal as an automated external defibrillator: to rescue a person suffering from sudden cardiac arrest. This occurs when there is an electrical problem in the heart that stops it from pumping properly. If the heart cannot be restarted promptly, the patient’s brain and vital organs will start to deteriorate, and the heart will ultimately cease to function.

When used in conjunction with immediate chest compressions, an automated or manual defibrillator can deliver electrical shocks to the heart within 3 to 10 minutes following cardiac arrest, which can stop the abnormal rhythms and allow the heart’s natural pacemakers to restart with a normal rhythm. This approach is effective for ventricular fibrillation or pulseless ventricular tachycardia but not for asystole or pulseless electrical activity (PEA).

Manual vs. Automatic Defibrillators: What Are the Differences?

An automated external defibrillator automatically analyzes the patient’s heart rhythm and calculates the power of the shock, while a manual defibrillator allows the operator to adjust the shock power (measured in joules) using the settings on the machine.

As the user sets the energy level, and the manual defibrillator lacks the same safety features as an AED, such as alerts when a shock is not recommended, advanced cardiac life support training is required to operate it properly.

Manual defibrillators generally come with three modes:

1. Synchronized cardioversion
2. External defibrillation
3. Internal defibrillation

Other Features of Manual Defibrillators

Manual defibrillators not only provide more control and customization but also possess additional capabilities that automated external defibrillators lack. Along with the ability to monitor oxygen levels in the blood (SpO2), carbon dioxide concentration in each exhale (ETCO2), and blood pressure (NIBP) when linked to other medical devices, manual defibrillators excel at performing non-invasive transcutaneous pacing and cardioversion.

What Is Non-Invasive Transcutaneous Pacing (NTP)?

Non-invasive transcutaneous pacing (NTP) involves providing current pulses to stimulate heart contractions, benefiting clinically stable patients at risk of rapid decompensation, such as those waiting for cardiac surgery, about to receive a permanent pacemaker, or experiencing early signs of a heart attack.

Electric Cardioversion

Cardioversion is a medical procedure that utilizes electrode pads on the patient’s chest to deliver electrical shocks to the heart. This can quickly restore a normal rhythm for patients experiencing arrhythmias or tachycardia.

Situations That Call for the Use of Manual Defibrillators

Manual defibrillators are recommended ONLY for medical professionals trained in advanced cardiac life support (ACLS) due to their ability to provide a customized electrical shock. Accurately interpreting electrocardiogram (ECG/EKG) data and understanding heart rhythms are critical in delivering the correct shock. In the case of sudden cardiac arrest victims, EMS personnel may use a manual defibrillator once they are transferred to the ambulance or hospital. Manual defibrillators are also suitable for treating sudden cardiac arrest in babies under one year old.

Cardiac arrest in children over one year old can be treated effectively with an AED. Simply switch the device to a pediatric setting with a pediatric key, pediatric button or pediatric pads (if using most other devices—like the HeartSine Samaritan PAD 350P, for instance).

Benefits of Using Manual Defibrillators

Manual defibrillators offer several advantages, making them an essential tool for medical professionals trained in advanced cardiac life support.

Manual defibrillators have several advantages for medical professionals providing advanced cardiac life support. One advantage is the potential to reduce interruptions to cardiopulmonary resuscitation to just a few seconds, compared to up to a minute with automatic defibrillators, due to the faster ECG data assessment by medical professionals. Another advantage is the ability to provide appropriate electric shocks to infants. In the absence of a manual defibrillator, chest compressions with rescue breaths, if the rescuer is trained, can help keep babies alive until emergency medical services arrive.

Drawbacks of Manual Defibrillators

The two main disadvantages of manual defibrillators are:

1. The operator may deliver an inappropriate electrical shock, which is why it’s essential they are only used by professionals who are trained in ACLS and never by a lay rescuer. If there’s no shockable rhythm, or if the level of shock is inappropriate for the patient, the patient may lose their life.

1. Manual defibrillators are not considered public access devices and as such are only available in medical settings such as hospitals and ambulances. In contrast, AEDs, by law, must be made available in most institutions and many commercial settings where people gather or engage in strenuous exercise.

Complementary Use of AEDs and Manual Defibrillators

When it comes to AEDs and manual defibrillators, it’s not all or nothing. A patient can be switched over from an AED to a manual defibrillator or the two can be used together.

If the AED and manual defibrillator are made by the same manufacturer, the electrode pads can simply be unplugged from the AED and plugged into the manual defibrillator.

When using medical devices from different manufacturers, they can be connected with a cable to access the features of a manual defibrillator without disrupting chest compressions or interrupting the analysis of the patient’s heart.

AEDs: The Optimal Choice for Untrained Rescuers

After discussing manual defibrillators and AEDs, the key point is that AEDs are typically appropriate for addressing sudden cardiac arrest in the community until medical professionals arrive. If advanced life support is required, manual defibrillators can be used.

If someone collapses and becomes unconscious, calling for an AED, dialing 9-1-1, and starting chest compressions immediately are the best actions to take. While more may need to be done, prompt action can help save a life.