Tuesday, August 21, 2012

Respiratory Therapy History Timeline

Compared to physicians, who can trace their roots to ancient times, and nurses, who can trace their roots to Clara Barton's Civil War heroics, the profession of respiratory therapy is a relatively young profession that can be traced only as far back as 1922.

We could trace it back to 5,000 B.C. when Egyptians inhale smoke from dried and crushed herbs burned on heated bricks to get breathing relief, or 100 A.D. when in India herbs were smoked in pipes, or even the 19th century when the first nebulizers were patented.

Yet the profession as we know it can only be traced back to 1922 when John Scott Haldane wrote about his research on oxygen in "The Therapeutic Administration of Oxygen."  It was this book that sparked interest in the therapeutic use in oxygen to treat diseases.

One of the first people to gain interest in attempting to create some sort of effective device for delivering therapeutic oxygen to patients was Dr. Leonard Hill of England.  In 1921 he announced his invention of an oxygen tent capable of delivering approximately 30 percnet oxygen.  It consisted of an airtight canopy that covered the patient and the bed.  (1) 

A major problem with these tents is they had no methods of controlling humidity and temperature, and patient's would become very uncomfortable inside them.  However, patients who needed supplemental oxygen to breathe would request the tent be taken down, and as soon as their breathing became labored again they'd request to be back inside.  So it was sort of a double edgled sword for these patients. 

In 1926 Alvin Barach invented an oxygen tent blew air over ice chips to cool the temperature inside the tent.  This made it so being inside the tents were much more bareable.   Usually these tents were reserved to patients with pneumonia and heart failure. (2) In 1931 John Emerson invented an oxygen tent that had a cooling system.  Preious devices were prone to rust and failure.  His cooling mechanism was  also ice.  (3)

In 1928 the Shaw respirator was introduced to the market.  This was the first electric and mass produceable negative pressure ventilator.  It was large, very expensive, noisy, and very heavy.  Yet it soon became very useful in keeping patients inflicted with polio and other such disorders that caused a person to stop breathing alive.  These ventilators, referred to as the tank or iron lung, were improved by John Haven Emerson, and in 1931 he introduced the Emerson Respirator.  Emerson's design was simpler, quieter, and had a method of manually breathing for the patinet should their be a power outage. Emerson's respirator would quickly become the most common iron lung used in hospitals in the U.S. and Europe. 

Nurses were initially responsible for oxygen equipment during the 1920s, and doctors and their technitians were initially responsible for setting up and manageing the iron lungs.  Yet lugging heavy oxygen tanks into rooms, and monitoring how much oxygen was in them, remained the task of the nurses.  Since the gauges were primitive, nurses would have to use formulas to calculate how long the tank of oxygen would last, and would have to switch tanks before they became empty. 

Complicating matters was that along with performing their nursing duties they also had to manage the oxygen tents and, eventually, iron lungs.  Their were a variety of gauges on the iron lungs that had to be monitored, along with making sure oxygen tanks used were likewise constantly full of oxygen.  To make matters worse, the gauges used were known to be innacurate (4)

Oxygen masks are designed by John Haldane and others, and are made of leather.  The first non-rebreather masks are fitted with vinyl bags for storing excess oxygen to be rebretahed, and had two one way valves, one on each side of the mask, to prevent air entrainment.  These masks at times turned out to be deadly when an oxygen tank ran empty.  And since the leather masks fit snug over the patient's face unlike modern plastic masks, one of the flaps would ultimately be required to be removed in order to prevent accidental asphyxiation.  This is the reason one of the flaps is missing on modern non-rebreathers. 

Vinyl nasal catheters were also designed by Haldane.  To humidify oxygen glass and metal humidifiers were invented.  Nebulizers were also made of glass, although until the 1930s a bulb had to be used to cause the medicine to turn into an aerosolized mist.  In the 1930s an electric nebulizer was invented and was mass produced that made for breathing treatments to become easy and more effective.  It became the job of nurses to administer such breathing treatments.  It was their job also to clean all this equipment between patients. 

By the 1940s nursing assistants are recruited to set up, monitor, and clean oxygen equipment.  They are ultimately referred to as inhalation tharapits and also pick up the task of doing the same for iron lungs and other respiratory equipment.  These first inhalation therapis are generally trained on the job, often referred to as OJTs (on the job training) and are usually poorly educated about what they were doing.  It was for this reason that an organization called the Inhalation Therapy Association was created in 1946 to form a means of educating inhalation therapists and further improving credentials and respect for the new profession.  The name was changed a few more times until it's current name of the American Associatino of Respiratory Care (AARC). 

By the 1930s oxygen is beginning to be piped into hospitals, and this continues during the 1940s.  For a while there is a fear that the profession will become to an end, as most inhalation therapits, now referred to as respiratory therapists, are often referred to as tank jockeys.  Yet the profession would evolve into more than just oxygen as in 1952 the first intermittent positive breathing machines become available.  These machines would at first be used to ventilate patients for short periods of time either via a rubber mask or cannula inserted into a tracheostomy.  Their are a variety of IPPB machines to hit the market, yet the most common are the Bennet PR 1 and 2, and by 1955 the Bird Mark 7. 

These machines were used as ventilators until the late 1950s and early 1960s until they and the iron lungs were ultimately replaced by more effective volume ventilators, the most popular of which were the Emerson Volume Ventilator that hit the market in 1964 and the MA1 that hit the market in 1967.  The Emerson ventilator was often referred to as a big green washing machine.  The MA1 was such a sturdy and compact unit that it was still around in 1997 when I became an RT at my present location. 

Monitoring and maintaining these machines was a complicated job, and respiratory therapists were needed.  While oxygen equipment became simpler over time, respiratory therapists were still required to monitor it's use, set it up, and clean it between patients.  RTs were also needed to do IPPB treatments.  During the early 1950s it became a common belief that giving aerosolized medicine, such as bronchodilators, by an IPPB machine three to four times per day would force the medicine deeper into the lungs.  This type of therapy was also believed to open collapsed alveoli and improve atelectic lungs in post operative patients.  It was also believed to prevent atelectasis.  For this reason, IPPB therapy became very common in hospitals and was ultimately used for more than just post operative patient.  It was used for COPD patients, asthma patients, and patients with just about any other lung disorder.  RTs were needed to do all this.

It was also during the late 1940s and 1950s that observations were made about COPD patients becoming lethargic and even dying due to exposure to too much oxygen.  This gave birth to the hypoxic drive theory whereby it was believed some COPD patients who were chornic CO2 retainers no longer used CO2 as their drive to breathe and instead used oxygen.  For this reason, it was believed that  too much oxygen would knock out their drive to breathe.  This was ultimately proven by Dr. E.J.M. Campbell in the 1950s based on a study of only four COPD patients.  In a report to the physicians in 1960 he reported his findings, and ever since doctors have been taught the hypoxic drive theory. 

The hypoxic drive theory is significant in that it was another reason for the importance of respiratory therapist monitoring oxygen therapy.  As therapist obtained more and more responsibility, it was realized the scope of knowledge needed for these individuals far exceeded their education and training.  This was particularly apparent on the weekends and night shifts when the least experiences therapists were working alone. (5)

By the 1960s most respiratory therapists have to study and take a test to work in the field, and this put an end to on the job training.  The first tests are oral, although eventually the written tests are created.  This also put an end to respiratory therapist being an ancillary staff, and instead RTs became a respected part of the patient care team. 

In these early days most respiratory procedures were profitable.  Many believe this was one of the reason so many IPPB therapies were ordered during the 1950s and 1960s.  Yet during the 1970s insurance companies started questioning the need for all these IPPB treatments.  Studies performed proved that nebulized aerosols provided better distribution of medicine into the lungs that IPPBs, as much as 35% better distribution.  Other studies proved that insentive spirometry was more effective than IPPBs in preventing and treating post operative atelectatis.  So IPPB therapy in this way started to decline.  However, it would be until the turn of the 21st century that most Bird Mark 7s would be bound and tied in the basements or sent to foreign countires or simply jettisoned into the trash pit.  These machines were durable, and my hospital still has one that doctors still put into use even to this day. 

In 1983 DRGs are created, and hospitals no longer get reimbursed for each procedure performed.  For this reason, many RTs fear their jobs will be eliminated. Instead, hospitals would be paid a flat fee for each patient.  In this way it was believed that hospitals would do as few procedures as possible when taking care of a patient.  Thus, it was thought DRGs would reduce hospital costs.  Yet the exact opposite happened.  In order to meet reimbursement criteria, many doctors simply diagnosed patients with diseases they thought were the most reimbursable, such as pneumonia, asthma, cardiac failure and COPD.  Perhaps it's for this reason, or just a coincidence, that asthma rates have skyrocketed since 1980. 

Since 1980 IPPB therapy has seen a decline, but aerosol therapy has seen a incline.  Doctors now order breathing treatments instead of IPPB therapy for all lung ailments.  In many cases, breathing treatments are ordered so the patient or family member thinks something is being done to make sure the patient or family doesn't sue the doctor.  Breathing treatments are also often ordered as part of order sets that make sure everything is ordered that may be needed for the patient to meet government set criteria for reimbursement.  This has all resulted in an exhorbitant amount of breathing treatments being ordered, and this has helped many RTs to continue to work.

Yet many hospitals have added protocols that allow the therapist to use his education and skills to only provide those services that are necessary and proven to work.  Many hospitals allow RTs driven protocols that allow RTs to decide who should get breathing treatments, and other protocols allow for RTs to decide what oxygen device to use, and what ventilator settings to use.  Many hospitals also have ventilator weaning and extubation protocols, and, of course, respiratory therapists are a major part of the hospital's critical care team responsible for attending all code blues, or instances where a patient doesn't look quite right, has severe difficulty breathing, or goes into cardiac or cardiopulmonary arrest. 

There are a miraid of responsibilities for today's respiratory therapists.  A minimum of two years is now required to work in most RT settings.  The field is continueing to grow and gain respect.  Surely there is a ways to go, but since nursing has had an extra 60 years to evolve, it may take another 60 years for the profession of respiratory therapy to reach the full level of respece of the nursing profession.  Still there are obstacles to cross, yet the profesion will continue to be a necessary one for many years to come. 
  1.  "Questions and Answers," The Modesto Bee, Thursday, Dec. 2, 1948
  2. Glover, Dennis W., "The History of Respiratory Therapy," 2010, page 40
  3. Branson, Richard D, "Jack Emerson:  Notes on his life and contributions to Respiratory Care," Respiratory Care, July 1998, vol. 43, no. 7, pages 567-71
  4. Glover, ibid, page 48
  5. Wyka, Kenneth A, Paul Joseph Mathews, William F. Clark, "Fundamentals of Respiratory Care," 2001, page 10, "The Late 1950s and 1960s: Organizational and Clinical Maturation."

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