Opinion: Patient Safety Update, or why a WWII bomber can save patients' lives

May 1, 2009

The practice of medicine has become too complex for ob/gyns to rely solely on their memories to keep patients safe. A mishap during the test flight of the B17 bomber taught its designers the value of a preflight checklist, and clinicians can likewise benefit from preprocedure checklists.

Flying Fortresses and medical checklists

Modern physicians are not the first to suffer such anxiety in high-stakes situations. Imagine how the technicians at the Three Mile Island Nuclear Generating Station felt when the alarms started sounding 30 years ago. Or imagine being a pilot in the US Army Air Corps in 1935. A year earlier, that service had requested designs for a bomber capable of carrying a significant bomb load at an altitude of 10,000 feet for 2,000 miles.2 The resulting design was the Boeing Model 299, which excelled in an early test flight. Unfortunately, development came to a screeching halt in October, 1935, when during a second test flight, the crew forgot to release the airplane's "gust lock," a device that held the bomber's movable control surfaces in place while the plane was parked on the ground.3 After takeoff, the plane climbed, stalled, and landed nose-first in the ground. An investigation concluded that the increased complexity of the new bomber had resulted in a pilot error, and the talking heads of the day wondered if it was too much plane for one man to fly. The solution was remarkably simple-the pre-flight checklist; and Model 299 became the B-17 Flying Fortress that helped win WWII. But its greatest legacy may be its prompting of one of the first great human factor engineering improvements-the safety checklist.

In the words of Atul Gawande: "Medicine today has entered its B-17 phase. Substantial parts of what hospitals do-most notably, intensive care-are now too complex for clinicians to carry them out reliably from memory alone."4 Checklists are now being adopted to guide staff through complex procedures that require systematic and comprehensive approaches. The use of a checklist seems especially promising in surgery. Haynes and colleagues recently published the impact of implementing a 19-item surgical safety checklist designed to improve team communication and consistency of care and, thus, reduce surgical complications and mortality.5 Between October 2007 and September 2008, eight hospitals in eight cities participated in the WHO's Safe Surgery Saves Lives program. Pre-intervention data were collected on clinical processes and outcomes from 3,733 consecutively enrolled patients 16 years of age or older undergoing non-cardiac surgery. These findings were compared to 3,955 consecutively enrolled patients following introduction of the checklist. The primary end point was occurrence of complications, including death, during hospitalization and within the first 30 post-operative days. The authors reported that mortality dropped from 1.5% before the checklist was introduced to 0.8% postintervention (P=.003). Inpatient complications occurred in 11.0% of patients at baseline and in 7.0% after checklist introduction (P<.001).