Most often a cascade of errors, rather than a single error, is necessary before patients actually suffer harm. When we do a root cause analysis, it is usually painfully apparent that avoiding any one of the errors in that cascade would likely have prevented the adverse patient outcome.
A dialysis patient was admitted via the emergency room to an acute psychiatric service because of abnormal behavior. He later suffered a cardiac arrest, precipitated by hyperkalemia. The RCA revealed multiple issues (delay in lab specimens being processed, poor panic value communication, poor communication between the psychiatry service and medical consultants, etc.). The EKG which had been obtained in the ER did show peaked T-waves highly characteristic of hyperkalemia. However, these were not readily recognized because that EKG had been run at ½ voltage/sensitivity unintentionally. The EKG machine had been used on other patients and during its previous use the ½ voltage/sensitivity was used. The technician running the EKG on the new patient did not recognize that the EKG was at ½ voltage/sensitivity and, though the scale was clearly marked at the beginning of the EKG, one would not realize that on rapid perusal of the strip. Several other patients had EKG’s with the reduced voltage/sensitivity but none were impacted by the EKG findings. This is an example of a latent error coming together with several more acute errors to result in adverse patient outcome.
At your facility, how is the EKG voltage/sensitivity recorded on the EKG? If the scale is indicated, is it indicated on each segment or is it just at the beginning of what might be a long EKG strip? Do the EKG machines revert to full voltage/sensitivity after each use? Do they require manual reversion or is the process automatic? If you are like most hospitals, you probably have EKG machines of varied ages. Some may automatically reset to standard voltage recording but others may not. Do you have a policy (and appropriate training and audit) to ensure that those requiring manual reset get reset immediately after each use?
Obviously, this comes back to a design issue. The optimal design would clearly delineate the voltage/sensitivity on all segments but would also automatically revert the voltage/sensitivity back to standard after each use.