What is the Difference Between Monophasic and Biphasic Defibrillator?

The main difference between monophasic and biphasic defibrillators lies in the waveform of the electric shock they deliver to the heart. Here are the key differences:

Monophasic Defibrillators:
Deliver a single-direction electrical shock from one electrode to another.
Require a high-energy electric pulse, typically ranging from 200-360 joules per shock.
Less portable and more bulky compared to biphasic defibrillators.
Biphasic Defibrillators:
Deliver a two-phase electrical shock, where the current travels from the first electrode to the second electrode via the heart, then reverses direction and runs from the second electrode back to the first via the heart.
Require less energy to administer a lifesaving shock, with lower peak electric current.
More portable, smaller, and lighter than monophasic defibrillators.

Biphasic defibrillators have become the industry standard for several reasons. They are smaller and lighter than monophasic defibrillators, making them easier to transport and use in public spaces. Additionally, biphasic waveforms have been shown to be more effective in mitigating skin burns and injury to the heart due to requiring significantly less current. Both monophasic and biphasic defibrillators have roughly the same efficacy in restoring normal heart rhythm, but biphasic defibrillators are considered safer and more convenient.

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What is the Difference Between Monophasic and Biphasic Defibrillator?

Comparative Table: Monophasic vs Biphasic Defibrillator

Monophasic and biphasic defibrillators are two types of devices used to deliver electrical shocks to the heart in order to restore a normal rhythm. Here is a table comparing their differences:

Feature	Monophasic Defibrillator	Biphasic Defibrillator
Waveform	Delivers a single, high-energy shock with a single electrical current	Delivers two-way shocks in quick succession, with a high-energy shock followed by a lower-energy shock that helps resynchronize the heart rhythm
Energy	Delivers a high-energy electric pulse, typically around 200-360 joules per shock	Delivers a bi-directional current flow with a less powerful shock than monophasic defibrillators
Efficacy	Both types of waveforms have roughly the same efficacy in defibrillation	Studies have shown a higher efficacy with regards to successful defibrillation compared to monophasic defibrillators
Patient Impedance	Cannot adjust for patient impedance	Can adjust impedance to work equally on different types of patients
Safety	Exposes patients to a higher peak electric current	Exposes patients to a much lower peak electric current, making them the safer and preferred type of defibrillators
Size and Portability	Monophasic defibrillators are larger and bulkier	Biphasic defibrillators are more compact and portable, leading to the advent of automated external defibrillators (AEDs)

In summary, while both monophasic and biphasic defibrillators are effective in defibrillation, biphasic defibrillators have become the more common choice due to their safety, lower peak electric current, and portability.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.