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A year ago, the Kansas City Star ran a story on Dead in bed (Marso 2018). The story begins with description of an 80 year old patient who had been admitted with a partial intestinal obstruction, apparently managed nonsurgically, who was now improving. The patient was scheduled for discharge the next day. Family mentioned she would fall asleep frequently while watching TV in the hospital but otherwise seemed returning to her usual self. The patient did not survive the night. She was found dead in bed. An autopsy was inconclusive for a cause of death, but no toxicology was done. Experts who reviewed the medical record commented that the doses and cumulative dosage of Dilaudid she had been receiving were quite high for an opioid-naοve elderly patient.
The article goes on to discuss with anesthesiologist Frank Overdyk, a leading voice in the movement for continuous monitoring to avert opioid-induced respiratory depression (OIRD), the need for continuous electronic monitoring tools that include pulse oximeters and capnography. Overdyk noted that hospitals often use these in ICUs but that only about 20 to 25 percent of hospitals have the capacity to use them at every bed and only about 1 percent do. The main reason, he said, is cost.
Speaking of Dilaudid, dont get us started! See our series of columns on the dangers of Dilaudid/HYDROmorphone listed below:
Khanna et al. (Khanna 2019) note that nearly half of in-hospital cardiorespiratory arrests occur on general care floors. Opioid-induced respiratory depression is one of the possible causes in many cases. Overdyk was a key researcher in the recently reported PRODIGY (Prediction of Opioid-induced respiratory Depression In patients monitoried by capnoGraphY) trial (Khanna 2019), a prospective study in 16 international sites. Subjects on general care floors who were receiving opioids had continuous monitoring of cardiorespiratory parameters, including heart rate, oxygen saturation, end-tidal CO2, and respiratory rate. Respiratory depression occurred in 41.4% of over 1000 patients. Predictors of respiratory depression were: age ≥70 to <80 or ≥80, male sex, major organ failure, chronic heart failure or cardiac disease, coronary artery disease, COPD or pulmonary disease, pneumonia, type II diabetes, hypertension, kidney failure and opioid naivety. Interestingly, negative predictors were BMI ≥35 and asthma.
The researchers were able to use a multivariate regression model to develop an OIRD risk prediction tool using age 70-79 or 80 and older, male sex, sleep disorders, hypertension, and opioid naivety. They termed this the PRODIGY score. This tool had high accuracy, using multiple measures of accuracy.
PRODIGY score ranged from 0 to 39, with low risk between 0 and 7, intermediate risk between 8 and 15 and high risk more than 15.
Khanna, the lead author of the PRODIGY trial report, notes in a video presentation that patients suffering cardiorespiratory arrest on general care floors have a much higher mortality than those who are continuously monitored, such as those in an ICU setting. 46% of patients in the PRODIGY study suffered at least one episode of respiratory depression. He notes that this frequency is almost double what prior studies had found. Why? Because PRODIGY used continuous monitoring. Most previous studies used episodic monitoring. Five variables were strongly related to the risk of respiratory depression: age > 60, male sex, presence of sleep disordered breathing, opioid naivety, and chronic heart failure. These were incorporated into the PRODIGY risk prediction score. High risk patients had a risk score of more than 15, low risk less than 8, and intermediate risk 8 to 15. He notes that all 3 risk categories had significant intergroup variation, so that intermediate risk was significantly greater than low risk and high risk significantly higher than intermediate risk.
Bradford Winters, M.D., discussed the challenges of recognizing clinical deterioration in patients outside the intensive care unit and notes the importance of early warning systems and continuous physiological monitoring in identifying such deterioration (Winters 2018). He discusses the evolution of Rapid Response Systems (RRS) and describes that such have both an afferent and an efferent limb. He goes on to describe the variety of early warning systems (EWS) developed over the years and has a great table of all those EWSs. But he notes a number of explanations as to why they generally failed to improve clinical outcomes.
Winters notes that surveillance monitoring may be a better way to collect and act on clinical data for a patient who is deteriorating on a general ward, but needs to overcome several challenging hurdles:
1) It needs to be mobile and wireless since general ward patients are usually ambulatory as compared to monitoring of ICU patients.
2) The mobile surveillance monitor must have adequate battery life.
3) The monitor needs to be comfortable and relatively unobtrusive.
4) The vital sign data collection should be continuous, since use of intermittently collected data may miss early signs of deterioration.
5) It needs to have an acceptable accuracy and a manageable false alarm rate.
Winters notes that studies of surveillance monitoring are still limited but the results are encouraging.
Verillo et al. (Verrillo 2019) compared continuous physiological monitoring to the current standard of clinical monitoring in patients admitted to a surgical unit. Continuous monitoring resulted in a statistically significant 27% decrease in the complication rate, and a clinically significant decrease in transfers to an intensive care unit and failure-to-rescue (FTR) events rate.
Opioid-induced respiratory depression, of course, has been the topic of many of our columns (see the full list below). The lack of continuous monitoring and, in particular, the infrequent use of capnography have been major impediments to identifying patients at risk for respiratory depression. Hopefully, future studies will demonstrate that use of the PRODIGY score and continuous physiological monitoring do result in improved clinical outcomes.
Of course, this all needs to be balanced against the risk of alarm fatigue. In our many columns on alarm fatigue we have stressed that alarms should alert healthcare professionals to clinically relevant conditions and that monitoring should be focused on those at risk and only for specified periods of time. For example, weve often noted that hospitals should avoid using telemetry outside accepted guidelines. Our hope is that risk assessment tools like the PRODIGY score will identify specific patients at risk so that continuous monitoring is not applied to all patients on a care unit, but rather selectively to those who truly need it.
Other Patient Safety Tips of the Week pertaining to opioid-induced respiratory depression and PCA safety:
· January 4, 2011 Safer Use of PCA
· July 13, 2010 Postoperative Opioid-Induced Respiratory Depression
· May 12, 2009 Errors With PCA Pumps
· September 21, 2010 Dilaudid Dangers
· November 2010 More on Preoperative Screening for Obstructive Sleep Apnea
· February 22, 2011 Rethinking Alarms
· May 17, 2011 Opioid-Induced Respiratory Depression Again!
· September 6, 2011 More Tips on PCA Safety
· December 6, 2011 Why You Need to Beware of Oxygen Therapy
· September 2012 Joint Commission Sentinel Event Alert on Opioids
· September 2012 FDA Warning on Codeine Use in Children Following Tonsillectomy
· July 3, 2012 Recycling an Old Column: Dilaudid Dangers
· February 12, 2013 CDPH: Lessons Learned from PCA Incident
· February 19, 2013 Practical Postoperative Pain Management
· March 3, 2015 Factors Related to Postoperative Respiratory Depression
· June 2, 2015 Reminders of Dilaudid Dangers
· August 11, 2015 New Oxygen Guidelines: Thoracic Society of Australia and NZ
· August 18, 2015 Missing Obstructive Sleep Apnea
· December 2015 Opioid Alert Fatigue
· March 2016 Guideline for Management of Postoperative Pain
· June 14, 2016 Nursing Monitoring of Patients on Opioids
· October 11, 2016 New Guideline on Preop Screening and Assessment for OSA
· December 6, 2016 Postoperative Pulmonary Complications
· June 20, 2017 Dilaudid Dangers #4
· October 3, 2017 Respiratory Compromise: One Size Does Not Fit All
· November 2017 Bad Combination: Gabapentin and Opioids
· November 21, 2017 OSA, Oxygen, and Alarm Fatigue
· July 31, 2018 Surgery and the Opioid-Tolerant Patient
· February 12, 2019
· March 2019
Some of our other columns on MEWS or recognition of clinical deterioration:
· February 26, 2008 Nightmares: The Hospital at Night
· April 2009 Early Emergency Team Calls Reduce Serious Adverse Events
· December 15, 2009 The Weekend Effect
· December 29, 2009 Recognizing Deteriorating Patients
· February 22, 2011 Rethinking Alarms
· March 15, 2011 Early Warnings for Sepsis
· October 18, 2011 High Risk Surgical Patients
· March 2012 Value of an Expanded Early Warning System Score
· September 11, 2012 In Search of the Ideal Early Warning Score
· May 2013 Ireland First to Adopt National Early Warning Score
· September 17, 2013 First MEWS, Now PEWS
· January 2014 It MEOWS But Doesnt Purr
· March 11, 2014 We Miss the Graphic Flowchart!
· July 15, 2014 Barriers to Success of Early Warning Systems
· November 11, 2014 Early Detection of Clinical Deterioration
· February 2015 Detecting Clinical Deterioration: Dont Neglect Clinical Impression
· April 28, 2015 Failure to Escalate
· September 8, 2015 TREWScore for Early Recognition of Sepsis
· October 2015 Even Earlier Recognition of Severe Sepsis
· December 15, 2015 Vital Sign Monitoring at Night
· June 2016 An EMR-Based Early Warning Score
· May 2018 Pediatric Early Warning System Fails
Our other columns on rapid response teams:
Marso A. 'Dead in bed' common term in hospitals. Here's why patients should know about it. Kansas City Star 2018; March 15, 2018
Khanna A, Buhre W, Saager L, et al. Derivation And Validation Of A Novel Opioid-Induced Respiratory Depression Risk Prediction Tool (Abstract 36). Society of Critical Care Medicine 48th Critical Care Congress San Diego, California February 1720, 2019; Critical Care Medicine 2019; 47(1): 18, January 2019
Video by Khanna
Khanna A. Pulmonology Consultant. Ashish Khanna, MD, on the PRODIGY Trial and Risk Score. Consultant360 2019;
Winters BD. Early Warning Systems: Found Dead in Bed Should be a Never Event. APSF Newsletter 2018; 33(2): 35-37
Verrillo SC, Cvach M, Hudson KW, et al. Using Continuous Vital Sign Monitoring to Detect Early Deterioration in Adult Postoperative Inpatients. Journal of Nursing Care Quality 2019; 34(2): 107-113