Dr. Peter Safar: The Three Phases of Cardiopulmonary Resuscitation

The Architect of the Life-Saving Alphabet

Every firefighter and EMT learns the ABCs of resuscitation: Airway, Breathing, Circulation. The sequence feels like common sense now. In the 1950s it did not exist as a system, and the person who did the most to assemble it was an anesthesiologist named Peter Safar.

Safar told the story himself in a 1989 personal history in the journal Resuscitation. The roots of modern CPR go back to around 1900, he wrote, but the ideas lay dormant for half a century. In the 1950s, a run of systematic research documented the A and the B; a chance rediscovery supplied the C; and the three were combined into basic life support and then integrated with advanced and prolonged life support into what he called cardiopulmonary-cerebral resuscitation.

The A and the B: Research, Not Intuition

Safar's contribution to the first two steps was experimental. His 1958 paper in JAMA examined the ventilatory efficacy of mouth-to-mouth artificial respiration and the airway obstruction that occurred during both manual and mouth-to-mouth methods. His 1959 paper in the Journal of Applied Physiology, "Upper Airway Obstruction in the Unconscious Patient," dealt with the problem every medic still fights: the soft tissues of the unconscious airway close it off.

The answer he documented was head-tilt and jaw-thrust to open the airway, followed by mouth-to-mouth ventilation. (Safar's own description is head-tilt and jaw-thrust, not the head-tilt/chin-lift most of us learned in class.)

The C: A Chance Rediscovery

The circulation step came from Johns Hopkins. In 1960, W. B. Kouwenhoven, James Jude, and G. Guy Knickerbocker published "Closed-Chest Cardiac Massage" in JAMA, showing that rhythmic compression of the sternum could produce circulation without opening the chest. Safar describes it as a chance rediscovery of something known around 1900 and then forgotten.

Safar's role was to put the pieces together: airway control, mouth-to-mouth breathing, and chest compressions as one sequence, A-B-C, that "everyone anywhere" could start.

The Three Phases of the Life Support Chain

Safar was explicit that basic life support was only a bridge. In his framework, BLS is just borderline emergency oxygenation, the first phase of a longer chain:

Phase II: Advanced Life Support

The drugs-and-defibrillation phase is the one EMS took onto the street. Safar trained the crews of Pittsburgh's Freedom House Ambulance Service, whose ambulances carried monitors, IVs, intubation kits, and defibrillators: ALS delivered before the hospital, not after.

Phase III: Prolonged Life Support and the Brain

Safar's longest project was the brain. He founded the International Resuscitation Research Center at the University of Pittsburgh in 1979, renamed the Safar Center for Resuscitation Research in 1994, built around the idea of saving people with "hearts and brains too good to die."

In a 2002 review in Critical Care Medicine, he summarized where that work had landed:

• In a clinically relevant dog model, mild hypothermia (34°C) started at reperfusion and held for 12 hours, combined with promotion of cerebral blood flow, extended the longest no-flow arrest that could be reversed to complete cerebral recovery from 5 to more than 10 minutes.
• Brief hypertension after ROSC was associated with improved outcome in patients.
• Mild hypothermia by surface cooling after prolonged arrest had been found effective in clinical studies in Australia and Europe.
• Most drug strategies for brain protection had been disappointing.

That is the scientific line that runs to post-arrest temperature management and blood pressure targets in today's protocols.

An Enduring Legacy

Safar did not invent every piece of CPR, and he said so. What he did was test the airway and breathing steps rigorously, combine them with the Hopkins compression work into one teachable sequence, and insist that the sequence was only the first link in a chain that ends in the ICU. Every waveform capnography trace we watch during a code, and every post-ROSC bundle we hand off, sits inside the system he described.

Sources

• Resuscitation (PubMed) — Safar, Initiation of closed-chest CPR basic life support: a personal history (1989)
• JAMA (PubMed) — Safar, Ventilatory efficacy of mouth-to-mouth artificial respiration (1958)
• J Appl Physiol (PubMed) — Safar et al., Upper airway obstruction in the unconscious patient (1959)
• JAMA (PubMed) — Kouwenhoven, Jude, Knickerbocker, Closed-chest cardiac massage (1960)
• Critical Care Medicine (PubMed) — Safar, Cerebral resuscitation potentials for cardiac arrest (2002)
• University of Pittsburgh — Safar Center for Resuscitation Research, history