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The most significant anesthesiologist of the 20th century died just weeks ago, on December 21, 2017. His name was William New, MD, PhD. Many of you have never heard of Dr. New, and don’t know what he was famous for, but in my opinion he was the Most Valuable Player of the anesthesia ranks in the last one hundred years.
William New was a Stanford anesthesiologist and electrical engineer. In 1978 Bill New invented the prototype of the modern pulse oximeter. In 1981 Dr. New founded and became Chairman of the Nellcor company, the manufacturer of the first commercially available pulse oximeter.
For my non-medical readers, a pulse oximeter is a medical device that indirectly monitors the oxygen saturation of blood by assessing the red color of pulsatile blood, usually in the patient’s fingertip. The original pulse oximeter was a stand-alone monitor, about the size of a cigar box, that was both portable and easy to use. The monitor displayed two numbers, the pulse rate and the oxygen saturation, as well as a vertical array of LEDs that mimicked the rise and fall of each pulse. The monitor emitted an audible beep, with high tones representing adequate oxygen levels and low tones representing unsafe oxygen levels. Without looking at the monitor, a clinician knew whether the patient was in danger, simply by listening to the pitch of the beep tone from the oximeter.
Steve Jobs changed our way of life with the introduction of the iPhone. In parallel, Bill New changed the world with the introduction of the pulse oximeter. No single device in the 20th century changed medical care more than the oximeter. Nellcor’s successful production, marketing, and sales efforts of their pulse oximeter changed not just anesthesia practice, but medical practice, forever.
Prior to the pulse oximeter, anesthesiologists had only unreliable measures of tissue oxygenation, such as observing how red the blood seemed when the surgeon made the initial incision into the patient. Undetected hypoxia could present as a sudden cardiac arrest. Anesthesia was a more dangerous undertaking without true second-to-second knowledge of the patient’s oxygenation.
In July 1984 during the first week of my Stanford anesthesia residency at the Santa Clara County Hospital, the entire medical center owned only three Nellcor pulse oximeters. Each morning the attending anesthesiologists would huddle and decide which three had the greatest need for the new technology. The remaining operating rooms would proceed without oximetry. The situation was better at Stanford University Hospital, where each operating room included a pulse oximeter—but there were no oximeters in the PACUs, preoperative units, or intensive care units.
It may be difficult for you to imagine the increased stress level when administering anesthesia without knowing what the patient’s arterial oxygen saturation is. The reassuring audible “beep-beep-beep” treble notes from the Nellcor were reassuring, and the descending bass notes of an acute desaturation struck terror into every one of us.
The market for the Nellcor pulse oximeter exploded between 1984 and 1986, and eventually all ICUs and acute care areas had oximeter monitoring. The oxygen saturation became recognized as “the fifth vital sign,” joining heart rate, blood pressure, respiratory rate, and temperature. On October 21, 1986, the American Society of Anesthesiologists made pulse oximetry a required standard monitor for all anesthetic care. The new standard read: “During all anesthetics, a quantitative method of assessing oxygenation such as pulse oximetry shall be employed. When the pulse oximeter is utilized, the variable pitch pulse tone and the low threshold alarm shall be audible to the anesthesiologist or the anesthesia care team personnel.”
In 1990 an American Society of Anesthesiology Closed Claims Study examined 1541 malpractice settlements, and showed that adverse respiratory events constituted the single largest class of injury (522 of 1541 cases; 34%). Death or brain damage occurred in 85% of these cases. Three-fourths of the adverse respiratory events were due to inadequate ventilation (196 cases; 38%), esophageal intubation (94 cases; 18%), and difficult tracheal intubation (87 cases; 17%). Most of the adverse respiratory outcomes (72%) were considered preventable with better monitoring (i.e. pulse oximetry plus capnography).
After the adoption of pulse oximetry and end-tidal carbon dioxide monitoring as standards, unexpected cardiac arrests from hypoxia or esophageal intubation became rare. Malpractice cases from respiratory events decreased, and malpractice insurance for anesthesiologists decreased in cost. In its landmark 1999 publication To Err is Human, the Institute of Medicine cited anesthesiology as the specialty that had made the most significant advances in patient safety.
Over the ensuing years, multiple companies produced pulse oximeters to mimic and compete with Nellcor. At the present time oximeters are ubiquitous, and are found in all clinics, emergency rooms, ICUs, PACUs, operating rooms, ambulances, critical care transport aircraft, and even in many homes. Today you can purchase a tiny finger oximeter from Walmart for $11.95
How big is the business of selling oximeters? The global pulse oximeter market was valued at $1.5 billion in 2015, and is projected to grow with a CAGR (Compound Annual Growth Rate) of 6.15%. Escalating healthcare costs are driving the market toward more home care, boosting the demand for remote patient monitoring devices, and increasing the demand for pulse oximeters.
I didn’t know Dr. New personally, although he and I attended the same alumni gatherings many times. He was congenial, humble, smart, and shunned the spotlight. He didn’t even have a Wikipedia page. He was nonetheless a celebrity among us. All Stanford anesthesia alumni knew the importance of his contribution to medical history. Dr. New continued his work as an engineer, entrepreneur and educator, and volunteered as an advisor for the Stanford Anesthesia Innovation Lab (SAIL), a medical device incubator focused on accelerating the development of anesthesia-related medical devices.
We anesthesiologists keep our patients alive, one at a time, aided by Dr. New’s discovery, and in total his discovery has kept millions of patients safe. The Stanford anesthesia department emailed out this brief note that Bill New wrote some years ago, which captured his thoughts regarding the future of our specialty:
As I ponder the future of ‘anesthesiology’ in a world where human physiology is unchanged but technology expands exponentially, the challenges and opportunities loom large. Moore’s Law and corollaries Rock’s Law + Edholm’s Law are driving us toward a technology singularity in anesthesia and critical life support, converting our human role to empathy and advocacy and no longer direct administration of agents/agonists, pills or potions, biochemical or otherwise.
I think back on academic departments and even entire schools/institutes of study at Stanford some fifty years ago that no longer exist or have morphed to fit the present world order. I see anesthesiology morphing over the next fifty in a comparable way, with technology (as in many fields) becoming the dominant paradigm.
Stanford needs to lead us into this new unknown vortex — and one of the best ways is how we train/acculturate our residents/fellows to embrace the 21st century, which is unlikely to become simply the elongation of the 20th century shadow. The past generation in academia blossomed to maturity with NIH grants, Medicare funding, peer review, publish or perish, tenure, big labs, hierarchical seniority, hospital hubs, risk-adverse regulation and a plethora of other customs and traditions. The accoutrements of academia yesterday will vanish. Anesthesia can — and must — join the new paradigm that technology now offers.
In a future column I’ll discuss the implications of Dr. New’s vision for the future of anesthesiology.
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