Mechanical ventilation is a life-saving therapy that catalyzed the development of modern intensive care units. The origins of modern mechanical ventilation can be traced back about five centuries to the seminal work of Andreas Vesalius. This article is a short history of mechanical ventilation, tracing its origins over the centuries to the present day. One of the great advances in ventilatory support over the past few decades has been the development of lung-protective ventilatory strategies, based on our understanding of the iatrogenic consequences of mechanical ventilation such as ventilator-induced lung injury.
These strategies have markedly improved clinical outcomes in patients with respiratory failure. The American Thoracic Society ATS has a long history, originating as the American Sanatorium Association in , which was established to promote the treatment and prevention of tuberculosis.
Since then, the scope of our mission has widened, and the Society has become the premier professional society in respiratory medicine, with more than 15, members worldwide who are dedicated to advancing our clinical and scientific understanding of pulmonary diseases, critical illnesses, and sleep-related breathing disorders.
Our members provide care for millions of people who suffer daily from asthma, chronic obstructive pulmonary disease, cystic fibrosis, sleep apnea, and lung diseases related to prematurity, to name a few. In celebration of our th anniversary, the ATS journals and ATS International Conference will highlight many of the advances in patient care and research in adult and pediatric pulmonary, critical care, and sleep medicine.
The ATS Discoveries Series is a new collection of articles and talks that features major scientific and clinical breakthroughs, which have changed the lives of the patients we treat, as told by leading scientists and clinicians.
With input from our membership, the topics range from the development of bronchoscopy to the discovery of surfactant, from insights into asthma pathogenesis to the potential of lung regeneration. Slutsky, M. I hope you enjoy learning about the seminal discoveries in respiratory medicine and their impact on patient care, now and in the future. Mechanical ventilation is a life-sustaining therapy for the treatment of patients with acute respiratory failure. It is a very common modality in intensive care units, and indeed the advent of its use heralded the dawn of modern intensive care units.
Interest in mechanical ventilation has increased markedly from both a research and a clinical perspective over the past 15 years since the publication of a milestone article in the New England Journal of Medicine by the ARDSNet investigators that highlighted the importance of a lung-protective ventilation strategy 1. Although recognition of the importance of lung protection appears to be relatively new, there are fascinating accounts dating back hundreds of years that link ventilation to the development of lung injury.
In this article, I provide a very brief, relatively personal perspective of the history of mechanical ventilation, with an emphasis on ventilator-induced lung injury VILI. I focus on historical aspects of both ventilation and resuscitation, because their histories are intimately intertwined. Due to space limitations, this will not be an in-depth review; the interested reader is referred to other reviews for greater detail 2 — 7.
Galen, the noted Greek physician and scientist who lived in the second century a.
Although he made great advances, his dissections were limited to animals, and he assumed that the organs of humans and animals were identical. He also studied respiration and taught that breathing was required to maintain the circulation i.
For almost the next 1, years, there were essentially no advances made in our understanding of ventilation, nor for that matter in any of the sciences; there is a good reason that a major part of this era was called the Dark Ages. However, Andreas Vesalius changed all of this in the midth century.
In , he published a brilliant treatise on anatomy entitled De Humani Corporis Fabrica , which likely had the first definitive reference to positive pressure ventilation as we know it today 9. This essentially describes what we currently do in the intensive care unit ICU when we perform a tracheotomy, insert an endotracheal tube, and apply positive pressure ventilation. This was a dramatic demonstration of the power of mechanical ventilation, but it was essentially forgotten for a century and not incorporated into widespread medical practice for several centuries.
Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome
Figure 1. Left Woodcut of the only known firsthand likeness of Andreas Vesalius reprinted from Reference Robert Hook was a natural philosopher and brilliant scientist. He was also the curator of the Royal Society of London and regularly performed experiments for the Fellows of the Society. His model was ingenious.
He used a dog in which he made cuts in the chest wall and pleura. He then used bellows to generate a constant flow of gas at the airway opening into the lungs; this constant flow then exited through the holes in the chest. In the 17th and 18th centuries, there were a number of approaches that were used to resuscitate patients—many not always as enlightened as those described above. It is important to understand that, as Hook stated, it was still not clear to physicians why people breathed and why people became pulseless.
It was believed that people were unconscious because of a lack of stimulation. This hypothesis led to a number of mostly unusual treatments whose goal was to stimulate the patients. In the late 19th century, ventilators based largely on currently accepted physiological principles were developed.
Essentially, ventilation was delivered using subatmospheric pressure delivered around the body of the patient to replace or augment the work being done by the respiratory muscles. In , Alfred Jones invented one of the first such body-enclosing devices The patient sat in a box that fully enclosed his body from the neck down Figure 2. There was plunger, which was used to decrease pressure in the box, which caused inhalation; the converse produced exhalation.
Also deafness. Figure 2. Body-enclosing box.
American Journal of Respiratory and Critical Care Medicine
One of the first known body-enclosing boxes; patented by Alfred Jones in Reprinted from Reference It was proposed to place these ventilators along the Seine River to help drowning victims. The spirophore had a metal rod that rested on the chest; movement of this rod was used as an index of the V t.
The first iron lung to be widely used was developed in Boston by Drinker and Shaw in and used to treat patients with polio One problem with these devices was that it was extremely difficult to nurse patients because it was difficult to get access to the patient's body.
To address this problem, Peter Lord patented a respirator room Figure 3 , in which the patient lay with her head outside the room 13 ; inside, huge pistons generated pressure changes, which caused air to move into and out of the lungs. The ventilator room had a door so that the medical staff could enter the ventilator to care for the patient. Of course these ventilators were extremely expensive, so James Wilson developed a ventilation room in which multiple patients could be treated Figure 3.
Respirator room. Pressure changes in the room were generated by huge pistons, which created pressure changes in the thoracic cavity, which in turn caused gas to move into and out of the patient who was connected via a manifold to a fresh gas supply outside the room.
Adapted from Reference And finally, one of my favorite ventilators was the pneumatic chamber developed by Wilhelm Schwake in Figure 4 Figure 4. Pneumatic chamber: Patented by Wilhelm Schwake in Germany in The resurgence of polio marked a watershed in the history of mechanical ventilation. Before this time, mechanical ventilation was believed to have some usefulness but was not used widely. Afterward, the benefits of ventilation were dramatic and obvious, leading to its widespread use worldwide.
At the height of the epidemic, 50 patients a day were being admitted to the Blegdams Infectious Disease Hospital, many with respiratory muscle or bulbar paralysis As such, he recommended tracheostomy and positive pressure ventilation. In total, by the end of the epidemic, approximately 1, students provided manual ventilation for a total of , hours One approach to the logistical challenge was to take care of all of these patients in one location.
This led to the first ICUs as we know them today.
Figure 5. Mortality rate from bulbar polio. On August 27, , tracheotomy and positive pressure ventilation were introduced arrow.
Much more than documents.
Adapted by permission from Reference The focus until this time was largely on providing ventilatory support i. This changed over the ensuing few decades with a greater focus on oxygenation failure, catalyzed by easier approaches for measuring blood gases; the identification of the acute respiratory distress syndrome ARDS 17 ; and the increased physiologic understanding of the impact of pressures in the lung on gas exchange.
Although Barach had investigated the use of positive pressure for the treatment of a number of diseases, including heart failure 18 , it was the observation by Ashbaugh of the possible usefulness of positive end-expiratory pressure PEEP three of five patients treated with PEEP survived, compared with two of seven not treated with PEEP , the understanding of atelectasis in supine patients, along with advances in ventilator design that heralded the widespread use of PEEP.
Over the past 60 years, many technical aspects of ventilators have dramatically improved with respect to flow delivery, exhalation valves, use of microprocessors, improved triggering, better flow delivery, and the development of new modes of ventilation e. In the s and s, there was a paradigm shift from controlled ventilation to partial ventilation support, then to pressure support ventilation.
Essentially, many current modes focus on increased patient control of ventilation to the point of allowing the patient to fully drive the ventilator e. These latter modes are still under physiological evaluation and only starting to be tested widely in clinical trials. The focus on increased patient contribution to ventilation is in line with our increasing understanding of ventilator-induced diaphragmatic dysfunction Many of these improvements have clearly led to much better ventilators and much better care of ventilated patients, but the major recent advances in mechanical ventilation are not related to these improvements but to our better understanding of the pathophysiology of ventilation, both the good and the bad.
Arguably the greatest advance over the past few decades in delivering mechanical ventilation has been in minimizing its side effects. The concept that ventilation may be harmful is certainly not new. In , John Fothergill published an essay in the Philosophical Transactions of the Royal Society of Medicine 11 in which he discussed a previous publication by William Tossach.
Tossach had helped resuscitate a coalminer who was apneic and pulseless. The surgeon felt 6—7 quick beats of the heart.
Fothergill clearly understood the possibility of injury caused by ventilation and in many ways can be viewed as the father of VILI, with his incredibly insightful conclusions years ago. This study was widely interpreted as suggesting that the lungs of a patient who was pulseless could not tolerate positive pressure ventilation. This likely set the field back many years.
Indeed, in the Royal Humane Society removed the use of bellows as well as mouth-to-mouth resuscitation from its list of recommended treatments Mechanical ventilation was originally introduced in patients with normal lung function, essentially to replace the neuromuscular pump e. In these patients ventilation was delivered with low pressures that were relatively safe.
Extracorporeal membrane oxygenation for ards in adults pdf to jpg
This is fundamentally different from its use to assist gas exchange in patients with severely diseased lungs, which are much more sensitive to mechanical injury. As this use of mechanical ventilation spread, it became apparent that negative pressure ventilators were less effective in maintaining gas exchange, and this, combined with technological advances and the experience of Ibsen and coworkers, led to the predominant use of positive pressure ventilation.
These ventilators could apply greater pressures, which made them more effective in facilitating gas exchange but, combined with the fact that the lung was already injured, led to recognition of adverse consequences e.
In the s Macklin and Macklin discovered the mechanisms leading to the development of pneumothoraces and barotrauma