Capnography, Patient-Controlled Analgesics, PCA

Does CMS Proposed Measure for PCA Safety Go Far Enough?

by Michael Wong

(This article is reprinted with the permission of Patient Safety & Quality Healthcare (PSQH).)

This is the question that I have been asking myself ever since Centers for Medicare & Medicaid Services (CMS) recently announced proposed quality measures it is considering for adoption through rule making for the Medicare program.

One of the measures under consideration by CMS (proposed quality measure #3040) calls for “appropriate monitoring of patients receiving PCA [patient-controlled analgesia].”

At first glance, this seems to address a critical patient safety issue: opioid induced respiratory depression. In its Sentinel Event Alert No. 49, “Safe Use of Opioids in Hospitals, The Joint Commission recently stated:

While opioid use is generally safe for most patients, opioid analgesics may be associated with adverse effects, the most serious effect being respiratory depression, which is generally preceded by sedation.

Monitoring patients receiving opioids by PCA is therefore essential for patient safety.

Just ask Lenore Alexander, whose daughter Leah had elective surgery for pectus carinatum, a fairly common condition where the sternum protrudes forward caused by an overgrowth of cartilage.

leah

“Leah was a healthy 11-year-old girl. In the surgery,” says her mother, “the doctors used an epidural anesthetic, which was left in place for post-operative pain management. I stayed with Leah that night and finally fell asleep after being up for more than 36 hours, ever since Leah checked in.  When I woke up two hours later, I found Leah dead. My screams were what alerted hospital staff that something had happened to Leah.”

“Leah was not monitored, either by a pulse oximeter or capnograph,” says Ms. Alexander. “Had she been monitored, perhaps she would still be alive today.”

For the article by Ms. Alexander on her daughter, please click here.

CMS’s proposed quality measure applies to “All patient admissions with initiation of an opioid via an IV PCA device that is active for more than 2.5 continuous hours”. Once PCA has been initiated, the proposed quality measure has two aspects:

  • When monitoring needs to occur.
  • What needs to be monitored.

When monitoring needs to occur

The CMS proposed quality measure provides that monitoring needs to be “documented” and the time between documentation must “not exceed 2.5 hours”. This means that a nurse or other caregiver must document the patient’s condition and do this in intervals of not greater than 2.5 hours.

However, recommendations by the Anesthesia Patient Safety Foundation provide that these “spot checks” are not sufficient:

Intermittent “spot checks” of oxygenation (pulse oximetry) and ventilation (nursing assessment) are not adequate for reliably recognizing clinically significant evolving drug-induced respiratory depression in the postoperative period.

Matthew Grissinger (director, error reporting programs at ISMP) explains why “spot checks” and relying on pulse oximetry as a measure of a patient’s oxygenation are not effective enough:

One reason why it is not effective is that a ‘periodic check’ and pulse oximetry would only catch an error, not prevent the error.

Additionally, the duration of the proposed CMS quality measure is “the first 24 hours after initiation of the first IV PCA opioid administration”. Surely, it would be more appropriate to monitor patients for the entire period that they are connecting to the PCA, rather than to stop monitoring after a predetermined period of time.

What needs to be monitored

The CMS proposed quality measure provides that patients using PCA be monitored for three physiological factors: “respiratory rate, sedation score and pulse oximetry”. Each factor is discussed below, with associated recommendations by key healthcare organizations and health experts:

Respiratory Rate

Measuring for respiratory rate is not enough. The Pennsylvania Patient Safety Authority recommends monitoring of patients include “frequent assessment of the quality of respirations (not just a respiratory rate) … ” [emphasis added].

Sedation Score

Sedation scores measure how the patient reacts to stimuli and the patient’s reaction are scaled, for example, from “no response to stimulus” to “anxious or restless”. However, Mr. Grissinger explains that a patient’s sedation score may not be an accurate measure, “ … 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.”

Pulse Oximetry

Monitoring a patient’s oxygenation by pulse oximetry is important. The Pennsylvania Patient Safety Authority recently stated, “However, while useful, pulse oximetry does not measure ventilation. Since oxygen saturation is a lagging indicator of respiration, pulse oximetry may not indicate a problem early enough for effective intervention. Pulse oximetry is even more problematic for patients who are receiving supplemental oxygen, since they may be adequately oxygenated even with dangerously depressed ventilation. Capnography, or end-tidal carbon dioxide monitoring, allows clinicians to track several indicators, but for purposes of PCA it is primarily used as a reliable monitor for respiratory rate, including apneic episodes. The Anesthesia Patient Safety Foundation (APSF) advocates monitoring both oxygenation and ventilation in all patients receiving PCA.”

Dr. Frank Overdyk (executive director for research, North American Partners in Anesthesiology, and professor of anesthesiology at Hofstra North Shore-LIJ School of Medicine) explains the importance of PCA in managing pain, but also the need for continuous electronic monitoring of patients:

Spot checks of SpO2, as are commonly taken on med/surg floors, need to be eliminated from patient monitoring practice because these single measurements  may mislead a provider into thinking the the patient is fine when in fact they may be close to the precipice of unrecoverable respiratory depression.

Entering a patient room and placing a pulse oximeter on their finger stimulates their consciousness and respiration sufficiently to falsely elevate their reading, particularly when they are receive supplemental oxygen. Once the provider leaves the room, this stimulus fades and the patient may lapse back into a dangerous level of respiratory narcosis.

Although the CMS proposed quality measure touches on a critical patient safety issue, the CMS measure only pays lip service to patient safety, as it goes against the recommendations of The Joint Commission, the Anesthesia Patient Safety Foundation, ISMP, and the Pennsylvania Patient Safety Authority.

As Mr. Grissinger says, “The CMS proposed quality measure regarding patient-controlled analgesia deals with a critical patient safety issue that hospitals need to urgently address. Errors with PCA occur and, unfortunately, sometimes with tragic consequences. However, for patients to be safe, we would strongly recommend that the proposed measure to monitor patients using PCA to include continuously electronically monitoring them with oximetry for oxygenation and capnography for adequacy of ventilation. In addition, standardization of PCA procedures would greatly reduce PCA errors and adverse events.”

Is incremental change enough? What do you think? Using the proposed quality measure example, has CMS gone far enough?

Please comment below or to send your comments directly to CMS, please email measureapplications@qualityforum.org (subject line: CMS Proposed Quality Measure #3040).

2 thoughts on “Does CMS Proposed Measure for PCA Safety Go Far Enough?

  1. lenoreac

    I found the CMS report to be very vague, and leaves it up to each hospital to determine who what where and how long. If they agree this is so important, why cant they set a standard?

  2. Pingback: Does CMS Proposed Measure for PCA Safety Go Far Enough ... | Patient Safety in Hospitals | Scoop.it

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s