May 2009

Did Those Old Medical Devices Really Work?
by
Louis Farah

Many years ago I attended a Los Angeles County paramedic update class. These are a part of my yearly continuing education that introduces new medical procedures for field use and/or any changes to county protocols.
Sitting with a bunch of old salts like myself that have been playing the paramedic game since the 1970’s, we marveled at the number of changes we’ve seen in medical care throughout the years.

At one time my paramedic unit carried five different pain medications, each used for something different; Demerol for muscle pain, Morphine for chest pain, Valium and Phenobarbital for seizures and Talwin for fractures.
We carried five different IV solutions and a variety of drugs used for drips. Paramedic units in Los Angeles County were stocked with virtually everything found in an emergency room because our paramedic program was still considered a “pilot program” that allowed emergency room physicians the latitude to order any medical procedure they felt was necessary to save a patient’s life.

The Wedworth-Townsend Act opened the door for paramedic programs throughout California. Unfortunately there were no standardized protocols for treatment. Each county had the ability to design and develop their own programs, and as a result, paramedic field treatment was as varied as the number of counties with paramedics.

However, one aspect of paramedic care was constant: The equipment we used.

Long before the advent of paramedics, ambulance services were using virtually the same emergency equipment made by a handful of manufacturers.

Early Resuscitators

Perhaps the most advanced piece of equipment in the early days of EMS was the use and delivery of supplemental oxygen via the resuscitator. Vintage equipment such as the old Emerson units used large and heavy tanks to power a device that forced air into the lungs of a patient. The standard procedure for anyone having breathing difficulties was the practice of putting a mask on their face with a tight seal to inflate the lungs.
Unfortunately, few of these people survived because the underlying cause of the medical emergency wasn’t alleviated by simply forcing oxygen into the lungs. However, for drowning victims and those overcome by smoke, the benefits far outweighed the negatives, so these units found a home on ambulances across the nation.

These resuscitators definitely had their limitations: They were big, heavy and bulky; It took two strong men to transport the unit from the ambulance to the patient; and they “cycled”.

Cycling was a design built into the system. To prevent damage to the lungs from over-inflation, once the resuscitator reached 40 pounds per-square-inch in pressure, the unit stopped pumping oxygen.
For those that suffered from chronic obstructive pulmonary disease, 40 pounds of pressure wasn’t enough to fill the lungs with air. As a result, for those patients with any type of obstructive lung disease, the Emerson resuscitator did more harm than good.

By the 1950’s, the theory of rescue breathing was making huge advancements. Although CPR had yet to be applied in a field setting, the medical community was starting to embrace the practice by numerous methods of rescue breathing including the use of the old arm-lift method, and eventually mouth-to-mouth rescue breathing.

With the evolution of the manual resuscitator, one of the most famous and well-known pieces of oxygen equipment came into vogue:
The green-cased E&J “Lifeport” oxygen resuscitator.

The good old E&J became the standard of the industry. Both the Los Angeles City and County Fire Departments used it as standard equipment on all of their apparatus, as did most other fire departments across the country. It too operated much like the Emerson unit, but it was much smaller and utilized lightweight “D” sized oxygen cylinders.

Both the Emerson and E&J resuscitators depended on the patient’s ability to breath in the oxygen in order to be beneficial. With the limitation of the cycling feature, those needing rescue breathing benefited little from the devices.

Perhaps the greatest advancement in the delivery of oxygen was the demand valve. At the press of a button, high-flow oxygen could be forced into the lungs without the worry of the device cycling, and thus, discontinuing the flow of oxygen into the lungs.

For rescue breathing on the go, the formidable ambu-bag was introduced in the 1960’s to ventilate a patient in distress. With the advent of cardio-pulmonary resuscitation, two rescuers could perform chest compressions and provide adequate oxygenation to a person with reasonable success.
The ambu-bag is used today as the primary mode of delivering rescue breathing to a patient outside of the hospital emergency room. The most widely used in-house device remains the ventilator, which can deliver a variety of oxygen concentrations and ventilation pressures and settings. The 1980’s saw the discontinuance of the demand valve resuscitator because of concerns associated with possible over-inflation of the lungs. Without a “pop-off” valve to prevent inflation pressure of above 40 pounds per-square-inch, the medical community seems to be more at ease with the ambu-bag that has that capability.

Even with the advancements of airway control with such devices as the endotracheal tube, the ambu-bag has undergone design changes to improve the delivery of oxygen into the lungs. Today’s ambu-bags have long connecting reservoir tubes to ensure 100% oxygen concentrations in the bag prior to deflation; New snap-on filters have color indicators to confirm the exchange of inhaled oxygen and exhaled carbon dioxide.

Although the old Emerson and E&J resuscitators are a huge part of EMS history and are standard props in our professional vehicles, their usefulness in today’s modern world of medicine has fallen by the wayside. However, before the advancement of emergency medical care, they were the standard of the industry.

Suction Devices

Just as important as delivering oxygen to a patient’s lungs was the establishment of a clear airway to facilitate the delivery of the oxygen to a patient’s lungs.

Perhaps the earliest device for clearing an airway was the simple bulb syringe. In fact, the bulb syringe is used today to clear the airway of an infant during delivery and a larger syringe can be used to clear fluids from the mouth and throat from most adults. However, when a larger volume of debris needs to be removed, the mighty Rico suction unit has become standard equipment in nearly all ambulances operating in this country.

The Rico suction unit gained popularity in the 1960’s because of the pressure generated by the suction unit and the large canister used to collect the secretions provided a much improved way of clearing a patient’s airway in an emergency. Whether the obstruction was blood or vomit, the Rico unit had the power and the capacity to handle the job.

There have been two units used in the field. The first was powered by manual suction created from the engine manifold of the ambulance being used. A hose was connected to the intake manifold and routed to the suction unit itself. Using the suction power of the engine, debris could be suctioned up into the catch canister. The power of the suction depended on the amount of suction generated by the ambulance’s intake manifold, which varied from ambulance to ambulance.

However, the cost of the suction unit was relatively cheap because early models did not have an independent motor that powered the unit. The mechanics were simple: Hook one end of the suction hose to the ambulance’s engine, hook the other end of the hose to the suction unit, and you were in business.

The modern Rico suction unit did away with the use of the engine’s manifold as the main source of suction in favor of a new unit that featured it’s own suction motor. The pressure generated by the motor was more consistent and could be regulated to meet the needs of individual patient requirements. Today, a suction unit is standard equipment in every ambulance manufactured in America.

As time went on, other companies entered the market with lighter and more compact devices. The Laedal Company produced a fine line of portable suction units that were powered by rechargeable batteries. Soon they became a standard as well. With the vast acceptance of the Laedal units, Rico soon concentrated their efforts on vehicle-based suction units while Laedal took over the portable market.

Entering the Modern Age of Paramedics

Basic life support devices such as oxygen tanks, resuscitators, ambu-bags and suction units have changed little prior to 1969. Yes, some improvements were made to make them more efficient. But the most significant evolution in the field of emergency medical services was the development of the paramedic.

No longer would citizens have to depend on a fast ride at break-neck speed to the nearest hospital to receive comprehensive emergency medical care. That advanced level of medical care would be brought to the scene of an emergency and the same high tech equipment used in the hospital would be used as well.

Perhaps the two most important tools were the portable heart monitor/defibrillator developed by the Datascope Corporation and the portable radio designed by Biocom.

Together, these two pieces of equipment brought those who had died back to life, or prevented one from dying.

Those experiencing cardiac arrest outside of an emergency room were doomed to a virtual death sentence. Without quick defibrillation, they would pass from “clinical death” to “biological death” with no possible chance for survival.

The use of the Datascope heart monitor/defibrillator, coupled with the proper cardiac drugs and the delivery of a counter-shock in a timely manner could convert a fatal heart rhythm into a normal heartbeat and save countless lives.

The use of the heart monitor/defibrillator with the patient’s electrocardiogram being transmitted to the hospital via the Biocom radio put a paramedic in direct contact with an emergency room physician. The physician could see the heart rhythm the paramedic was seeing in the field, and timely treatment was initiated to prevent a potentially-fatal heart rhythms from occurring.

The impact was immediate.

Prior to the introduction of paramedics, nearly 90% of all cardiac cases never made it to the hospital alive. A heart attack outside of a hospital meant certain death. Today, over 90% of all heart related patients not only make it to the hospital alive, but they survive and go on to live productive lives.

Most cardiac monitor/defibrillators today are standard tools in treating a variety of cardiac emergencies. Developments during the last thirty years include the use of twelve leads to view the entire heart from front to back, and heart pacing capabilities for those patients in acute heart failure. Some units, such as the Life Pack 12, even record voice conversation at the scene of the emergency for documentation at a later time.

Perhaps the most important piece of equipment was (and still is) the radio used by the paramedic base station hospital that receives the assessment and report from the paramedics and relays back medical treatment to the paramedics in the field.

The base station radio not only receives voice transmissions from paramedic crews, but receives the patient’s EKG rhythm as well. Advanced life support treatment is much more sophisticated than ever before and current protocols require much more documentation of medical conditions before and after treating the patient.

At the time of their use, these medical devices were considered state-of-the-art and were widely used. Just as the ambulance has improved in performance, style and convenience, medical devices have steadily improved to meet the new protocols of emergency medical care in a pre-hospital setting.

For those of us that have been involved in the field of emergency medical services since the 1970’s, the changes have been astonishing. We are doing medical procedures and using equipment that is even more advanced than ever before.

As to the question of did these devices actually work?

Yes, indeed they did!