by Michael Wong
Pain control in hospitals using patient-controlled analgesia (PCA) need to be made safer. In this interview with Michael Wong of the Physician-Patient Alliance for Health & Safety (PPAHS), Tim Ritter (Senior Patient Safety Analyst at the Pennsylvania Patient Safety Authority) and Matthew Grissinger (Director, Error Reporting Programs at ISMP) discuss PCA pumps and why reliance on periodic checks by caregivers and pulse oximetry can only catch an adverse event, but not prevent an adverse event from occurring. For patient safety, PPAHS encourages continuous electronic monitoring, including the use of both capnography and pulse oximetry, of all patients using patient-controlled analgesia (PCA).
According to the Institute for Safe Medication Practices (ISMP), the technology and knowledge exist today to prevent errors associated with use of patient-controlled analgesia. As ISMP Vice President Judy Smetzer says, “The solutions are available. We know how to prevent these errors, while preserving the benefits of this patient-centered technology.”
Accordingly, states ISMP President Michael Cohen, “Hospitals need to address the causes of PCA errors now. Appropriate education of patients, family members, and hospital staff is key.”
Despite these statements by ISMP and many other patient safety and medical organizations, questions persist about how often PCA errors occur, whether existing medical practices are sufficient, and what can be done about PCA errors.
So, to answer some of these questions, Michael Wong of the Physician-Patient Alliance for Health & Safety asked Tim Ritter (Senior Patient Safety Analyst at the Pennsylvania Patient Safety Authority) and Matthew Grissinger (Director, Error Reporting Programs at ISMP).
What do you say to people who contend that PCA errors don’t happen frequently and question why you and other organizations are concerned about this issue?
Ritter: “Over the six-year period from June 2004 to May 2010, data collected by Pennsylvania Patient Safety Authority revealed that there were approximately 4,500 reports associated with PCA pumps. Moreover, U.S. Food and Drug Administration’s (FDA) Manufacturer and User Device Experience (MAUDE) database demonstrates that PCA-related device events are three times as likely to result in injury or death as reports of device events involving general-purpose infusion pumps.”
Grissinger: “Honestly, I don’t know of any hospital that questions the problems with the programming of any infusion pump, let alone a PCA pump. If people did question whether these types of events take place they may base that statement purely on not seeing a large number of medication error reports on this problem. But, as we’ve seen in most organizations, error reporting only captures from 4-10% of the actual events that take place in a hospital.”
How do the number of errors with PCA compare with other reported medical errors?
Grissinger: “Since there is a large number of events not reported, it makes it difficult to quantitatively compare one type of a problem with another. Anecdotally I can tell you from the experience of reviewing many medication error reports that there are numerous examples of misprogrammed general infusion pumps that outnumber PCA pumps that are misprogrammed, but that is also a reflection of the vast number of “general” medications programmed on an infusion pump compared to the number of opioids programmed with a PCA pump.”
Healthcare facilities often rely upon periodic checks by caregivers and pulse oximetry to ensure patient safety. Why is this not effective enough?
Grissinger: “One reason why it is not effective is that a “periodic check” and pulse oximetry would only catch an error, not prevent the error. ISMP would recommend that nurses have an independent double check (where one person programs the pump and a 2nd nurse independently checks what is programmed). But we’ve seen organizations struggle with this process, for example, finding that extra person to do the check may be difficult with all of the other duties of a nurse.
“Moreover, current standard methods for assessing a patient’s level of consciousness do not take into consideration that overly sedated patients can be aroused and respond to questions. Even though these patients can be aroused for a brief period of time and may in fact be able to speak, they immediately fall back into a state of oversedation. Accordingly, ISMP recommends observing the patient unobtrusively and noting both respiratory rate and depth of respiration in the absence of any stimulus.
“Lastly, there’s too much reliance on pulse oximetry readings, which can offer a false sense of security since oxygen saturation is usually maintained even at low respiratory rates, especially if supplemental oxygen is in place. As ISMP President, Michael Cohen has said, “Capnography measures the end tidal volume of carbon dioxide, which is a more reliable indicator of respiratory depression and has previously been employed in limited areas such as critical care units.”
For more on reducing patient harm from opiates, please go the ISMP’s Medication Safety Alert. In that Alert, ISMP encourages the following – “ Establish guidelines for appropriate monitoring of patients who are receiving opiates, including frequent assessment of the quality of respirations (not just a respiratory rate) and specific signs of oversedation.”
Moreover, in establishing guidelines, ISMP also points out, “ Do not rely on pulse oximetry readings alone to detect opiate toxicity. Use capnography to detect respiratory changes caused by opiates, especially for patients who are at high risk (e.g., patients with sleep apnea, obese patients).”