Patient Safety in the Cath Lab: Take a Time-Out, Part I of III

During my training, I witnessed an unfortunate and potentially preventable complication. An elderly woman with hypertension, diabetes, and chronic kidney disease presented for a planned percutaneous coronary intervention (PCI).  The labs before her diagnostic angiogram 3 weeks earlier had shown a creatinine of 1.5 and normal electrolytes. Her labs were drawn on the morning of her PCI procedure, but came back partially hemolyzed.  They were redrawn, but it would take up to an hour before a result was returned. 

The physician was told labs were redrawn, but proceeded with PCI. After the first balloon inflation, the patient developed ventricular tachycardia and fibrillation that was completely refractory to defibrillation and CPR.  The labs that morning subsequently returned a creatinine of 1.8 mg/dL and potassium level of 6.7 mEq/L.

Preventable medical errors

The Institute of Medicine Report in 1999 estimated that errors in health care caused between 44,000-98,000 deaths annually, equivalent to one airplane crash daily.  In medicine, we have a tendency to try and assign blame, and label people as “bad” doctors or “bad” nurses. However, experts in error analysis tell us that the old adage “to err is human” is completely correct, and that anyone can make an error or slip, especially if placed in a challenging environment. The cath lab is a particularly stressful environment: time pressures are high (e.g., ST-elevation myocardial infarctions), our work can mean the difference between life and death, and our communications are primarily verbal.  

Factors contributing to errors

A critical concept in the safety literature is that errors never occur in isolation, but rather occur as a part of a system. That system should, ideally, be thoughtfully designed to prevent medical errors, catch medical errors before they can cause harm, and mitigate any harm produced. More commonly, our health care systems are not designed this way, and have many factors that contribute to medical errors (Figure 1).

In the Swiss cheese model of accident causation, errors can only harm a patient when multiple factors occur simultaneously. These might include organizational factors (high workload, staffing levels, inadequate training), error-producing factors specific to the situation (complex patients, repetitive tasks, knowledge deficit, interruptions), active failures (misjudgment, lapses, policy violations), and inadequate defenses (lack of systematic communication, double-checks, or alerts). Our responsibility to our patients is to create systems of health care that are as close to “foolproof” as possible. In a series of articles, I will review what experts in safety have to say about medical errors, and how we might apply them to the cath lab.

In the above example, where labs were not checked before PCI, it might seem easiest to blame the physician, but could the complication have been avoided if the labs had been automatically reordered as a STAT? Should it take an hour to return such results? Should the cath lab have point-of-care testing for blood gases and electrolytes for these situations (i.e., iStat), as we do for ACT? How recent do blood tests have to be? Typically, one-week old blood tests are considered acceptable, but that might be insufficient for a dialysis patient and too strict for a patient with completely normal labs and renal function 2 weeks earlier. Was the physician made aware that the lab results were not yet available, or did he presume that they were within normal range because no one told him otherwise as part of a time-out?

Poorly performed or missed time-outs are deadly

The concept of a preprocedural “time-out” or checklist has become an established safety practice throughout health care. A checklist forces the team to take a systematic approach to reviewing the issues specific to an individual patient. Checklists are most valuable where most of the procedures performed are routine, where staff may become complacent with the risks of a procedure and overlook preventable safety risks.

A critical example of the importance of checklists (like so many examples in the safety literature) comes from the aviation industry. In 2005, Helios Flight 522 took off from Cyprus towards Athens. The crew of the prior flight noted noises from the door, and a ground engineer performed a pressurization check, which required him change the system to “manual” mode. The engineer forgot to reset the system to “auto” mode, which automatically pressurizes the cabin upon reaching altitude. The flight crew overlooked this change on three separate pre-flight checklists (likely because 100% of the time they had checked it before, it was in the correct mode). As the flight gained altitude, the gradual loss of cabin pressure disabled the passengers and crew, and the airplane flew on autopilot until it ran out of fuel and crashed into a mountain, killing all 121 aboard. Faithful attention to the items on the checklist would have likely avoided this deadly accident, which was entirely due to human factors.

For the cath lab, the typical pre-procedure time-out consists of a limited review and confirmation of the patient’s identification, planned procedure, access site, equipment, allergies, laboratories, and prior imaging (Figure 2). This time-out ensures that you have the right patient, the right procedure planned, and the right access site prepped. Performed correctly, it ensures that all team members are aware of the patient’s labs (including abnormal or pending labs) and allergies. This pre-procedure time-out is mandated by the Joint Commisison, and should be already familiar to anyone working in the cath lab. 

A second time-out?

However, while important, this initial time-out is often inadequate when the decision to proceed with PCI is often made only after the diagnostic angiogram is completed. For such ad hoc procedures, the decision to proceed with PCI may not be completely discussed or thought through, even though the intervention carries a much higher risk of complications than the diagnostic procedure. As a result, in November 2014, the Society of Cardiovascular Angiography and Interventions Quality Improvement Toolkit committee published an ad hoc PCI checklist that should be completed before PCI is performed (Figure 3).  

I personally prefer my own mnemonic (“A, E, I, O, U”) to remind me and my staff of the pertinent issues involved before performing a PCI, and to allow for discussion of the appropriateness of proceeding:

• Antithrombotic
  • Heparin or bivalirudin?
  • Clopidogrel, ticagrelor, prasugrel, glycoprotein inhibitor?
• Environment/equipment
  • Do we have an available bed?
  • Do we have the appropriate procedure equipment (balloons, Rotablator) and rescue equipment (intra-aortic balloon pump, Impella) available?
  • Is this patient appropriate for an institution without on-site CT surgery?
• Indication
  • What is the indication for fixing? Acute coronary syndrome, stable angina?
  • Are the appropriateness use criteria satisfied?
  • Is fractional flow reserve needed to prove indication?
• Outcomes
  • Would coronary artery bypass graft surgery be better than PCI? 
  • Would a bare-metal or drug-eluting stent be more appropriate for this patient?
  • Is the patient likely to be compliant with dual antiplatelet therapy?
• Unexpected complications
  • What are the potential complications of this procedure (dissection, shock, vessel closure)? Are we prepared for them?

With a second time-out for PCI, all of the issues specific to PCI that were not discussed at the initial time-out are discussed and communicated to the cath lab team. Everyone has a chance to listen, discuss, and have an idea of the plan, so they can have the drugs, equipment, and planned disposition that will be needed. The second time-out thus aids the entire cath lab and hospital in preparing for the procedure, reducing the risk of miscommunication, delays, and errors. It should become part of everyone cath lab’s process. 

Are we done?

Finally, a “closing time-out” may be helpful for long or complex procedures, so that you really are sure that you are done before pulling out that sheath. It is very easy to get distracted during a procedure, especially when teaching fellows. On several occasions, I have forgotten to shoot a bypass graft that I meant to, or on reviewing the films, missed a lesion that should have been stented. Going over a closing checklist, preferably with the entire cath lab team helping, will ensure that everything has been done to maximize the outcome for the patient. Components of a “closing time-out” might include:

• Is the procedure really done?
• Are sponge/needle counts correct (for pacemakers)?
• Are all of the vessels and grafts imaged?
• Did we do a left ventriculogram?
• Did the patient get his clopidogrel, prasugrel, or ticagrelor before leaving the cath lab?
• How do we plan on managing the access site?
• What type of bed should the patient go to?

If checklists and timeouts seem boring or repetitive, keep in mind that that is exactly when they are needed most. Ninety-nine percent of the time, when you check the battery in the temporary pacemaker or that the defibrillator is plugged in, it will be fine. But if you ignore it or treat it casually, then that is when you will miss something that you and your patient will regret.

We’ll review more examples of both aviation and medical errors in future issues, and how we can learn from them to make our labs safe for our patients. 

If you have a question and/or case example that you would like to share, I encourage readers to contact me by email at arnold.seto@va.gov. 

References

1. Institute of Medicine Report, To err is human: building a safer health system.  Kohn L, Corrigan J, Donaldson M, eds. National Academy of Sciences. 2000.  Available online at: https://www.nap.edu/books/0309068371/html. Accessed April 20, 2016.
2. Blankenship JC, Gigliotti OS, Feldman DN, Mixon TA, Patel RA, Sorajja P, Yakubov SJ, Chambers CE; Society for Cardiovascular Angiography and Interventions. Ad hoc percutaneous coronary intervention: a consensus statement from the Society for Cardiovascular Angiography and Interventions. Catheter Cardiovasc Interv. 2013 Apr; 81(5): 748-758. doi: 10.1002/ccd.24701.
3. TeamSTEPPS 2.0. Team Strategies & Tools to Enhance Performance and Patient Safety. Agency for Healthcare Research and Quality Pub No 14-0001-2. Available online at: https://www.ahrq.govhttps://s3.amazonaws.com/HMP/hmp_ln/imported/wysiwyg/professionals/education/curriculum-tools/teamstepps/instructor/essentials/pocketguide.pdf. Accessed April 20, 2016.