In our July 15, 2014
Patient Safety Tip of the Week “Barriers
to Success of Early Warning Systems” we again lamented the fact that early
warning systems (EWS) to detect clinical deterioration of patients earlier have
yet largely failed to live up to their promise. While the logic behind such
scoring systems seems well-founded there has been a paucity of high-level
evidence that such systems lead to substantial improvement in patient outcomes.
Because of that and other factors, hospitals in the US have been very reluctant
to adopt early warning scores into routine practice even as hospitals in the UK
have been mandated to adopt such systems.
In that column we
discussed an excellent study in the nursing literature (Watson
2014) that provided great insight into the barriers that impact
implementation of an early warning system. Some of those barriers included:
1) Delays in charting vital signs
2) Poor consistency between charted vital signs
and those used in the early warning systems (EWS)
3) Multi-tasking by RN’s
4) Recording vital signs first on paper, later
entering into the computer
5) Lack of computer availability or
functionality
6) Excess log-on times
7) Preference for not charting in front of
patient/family
8) Lack of incorporating the RN’s impression of
the patient status into the EWS
9) General perception by RN’s that the EWS was
no better at predicting deterioration than their own clinical impression
Watson and
colleagues suggested changes to the physical environment and improved
technology interfaces to support real-time data entry as ways to improve
usefulness of the EWS:
1) Bedside computer access or use of smartphones
or tablets for documentation
2) Have EMR’s automatically populate VS into the
early warning score tool
3) Re-examination of RN and non-RN tasks,
perhaps returning VS assessment to RN’s so that data collection and
documentation would be integrated
4) Add RN concerns or family concerns to the
criteria for the score
Now a new study that
included many of those recommended practices into an
EWS implementation has documented substantial improvement in mortality (Schmidt
2014). They implemented at two general hospitals in England an electronic
physiological surveillance system (EPSS)
which uses wireless handheld computing devices to replace a paper-based vital
sign charting and clinical escalation system. After implementation of the
system crude mortality for 56 diagnostic groups fell from 7.75% to 6.42% in one
hospital and from 7.57% to 6.15% at the second hospital. They conclude that
using technology specifically designed to improve the accuracy, reliability and
availability of patients’ vital signs and early warning scores allows early recognition
of and response to patient deterioration, resulting in improved mortality rates
In our February 22,
2011 Patient Safety Tip of the Week “Rethinking
Alarms” we highlighted a paper by Lynn and Curry (Lynn 2011)
that described 3 patterns of unexpected
in-hospital deaths and discussed the problems with threshold-based alarms (almost all currently used
alarm systems use threshold-based principles) in detecting early deterioration.
Indeed, they posit that threshold-based
alarms themselves often cause us to miss signs of early deterioration
and make a case for implementation of “smart” alarms that integrate clinical
data from multiple sources. The core concept of early warning systems, of
course, is that using multiple factors should facilitate identification of
clinical deterioration rather than just using a single factor.
In a very thoughtful commentary on the Schmidt study, David
Bates and Eyal Zimlichman (Bates
2014) note the confluence of four major trends that should help overcome
the barriers noted above. They note that the near-universal use of electronic
medical records, better physiological sensors, background analytics, and mobile
technology should facilitate earlier detection of clinical deterioration. They
note that the Schmidt study still relied on intermittent vital sign measurement
rather than using more continuous physiological measurements. So the potential
to further improve this system is even greater. They do, however, note that the
danger of alert fatigue might raise its ugly head and recommend caution and the
need to address the false positive issue. They also acknowledge the importance
of recognizing sociotechnical factors that might undermine such systems.
Hospitals have more and more adopted use of “middleware” and
alerts delivered via mobile technologies to direct conditions needing attention
to the healthcare workers who should provide that attention. That obviously is
the wave of the future. It minimizes the “noise” of alerts and alarms going to
everybody and gets them to the staff accountable for responses. But even then
issues may arise. In our February 4,
2014 Patient Safety Tip of the Week “But
What If the Battery Runs Low?” we noted a scenario where a patient
event triggers an alarm that is sent to the primary nurse expected to respond
but the battery in her cell phone has failed and she never receives the alert.
Fortunately, the escalation procedure built into your system sends the alert to
a secondary nurse who responds to the patient and no harm comes to the patient.
Technological advances solve multiple problems but may introduce new potential
problems as well.
In a related issue, early warning systems (EWS), of course,
are intimately tied to rapid response teams (RRT’s) and rapid response systems
(RRS’s). Like the evidence base for EWS, the evidence base for the success of
RRT’s and RRS’s in improving patient outcomes has been mixed at best. The
Medical Journal of Australia has just indicated it will be doing a series of
articles exploring how RRS’s have changed approaches to patient safety,
influenced end-of-life care, and the changing nature of cardiopulmonary arrest
teams (Hillman
2014). One issue that has always popped up regarding both RRT’s and
cardiopulmonary arrest teams is whether adverse events occur in other locations
when team members have to abandon those locations to respond to the emergencies
elsewhere. A new study answers that question (Concord
MET Study 2014). The bad news is that disruptions of normal care routines
and inconvenience to staff do occur in such situations. The good news is that
it is very rare for adverse events or patient harm to come about because of
those events.
Hopefully the new work by Schmidt and colleagues will
rekindle interest in both early warning systems (EWS) and rapid response
systems (RRS). As we have mentioned in several of our own columns on rapid
response teams, the problem is not with the response teams. Rather it is with
our poor recognition of early clinical deterioration.
Some of our other
columns on MEWS or recognition of clinical deterioration:
Our other columns on
rapid response teams:
References:
Watson A, Skipper C, Steury R, et
al. Inpatient Nursing Care and Early Warning Scores: A Workflow Mismatch. J Nurs Care Qual 2014; 29(3):
215-222
Schmidt PE, Meredith P, Prytherch
DR, et al. Impact of introducing an electronic physiological surveillance
system on hospital mortality. BMJ Qual Saf 2014; Published
Online First: 23 September 2014
http://qualitysafety.bmj.com/content/early/2014/09/23/bmjqs-2014-003073.abstract
Lynn LA, Curry JP. Patterns of unexpected in-hospital
deaths: a root cause analysis. Patient Safety in Surgery 2011, 5:3
(11 February 2011)
http://www.pssjournal.com/content/pdf/1754-9493-5-3.pdf
Bates DW, Zimlichman E. Finding
patients before they crash: the next major opportunity to improve patient
safety. BMJ Qual
Saf 2014; Published Online First: 23 September
201
http://qualitysafety.bmj.com/content/early/2014/09/23/bmjqs-2014-003499.full
Hillman KM, Chen J, Jones D. Rapid response systems. Med J Aust 2014; 201 (9): 519-521
The Concord Medical Emergency Team (MET) Incidents Study
Investigators. Incidents resulting from staff leaving normal duties to attend
medical emergency team calls. Med J Australia 2014; 201: 528-531
Print “PDF
version”
http://www.patientsafetysolutions.com/