A few columns ago we talked about our difficulties in early detection of patient deterioration (see our Februrary 22, 2011 Patient Safety Tip of the Week “Rethinking Alarms”). We highlighted a very insightful study by Lynn et al (Lynn 2011) that described many of the flaws in current patient monitoring systems, particularly those monitoring for respiratory complications. And we stressed the need for “smart” alarm systems that can monitor multiple parameters in an integrated fashion to detect deterioration earlier.
Much of the work looking for such smart “early warning” systems has focused on sepsis. Over the past few years the Surviving Sepsis Campaign has focused on improving morbidity and mortality from sepsis. Timely antibiotics and goal-directed therapy, with adequate fluid rescuscitation are critical components in management of sepsis. The Surviving Sepsis Campaign recommends a group of interventions, each of which has some evidence base, delivered as a “bundle”. Compliance with all the elements of the bundle has been associated with sustained reduction in mortality from sepsis in multiple sites (ICU, ER, med/surg wards) (Levy 2010). In medical and surgical ICU’s compliance with the bundles was associated with not only improved mortality but also with reduced ICU and total hospital length of stay (Castellanos-Ortega 2010).
Studies have demonstrated that earlier antibiotic therapy confers a mortality benefit. The Surviving Sepsis Campaign protocols focus on delivery of antibiotics within 3 hours of an emergency department admission and one hour of a non-emergency department admission. One study confirmed the impact on mortality of antibiotic administration in the emergency department within the first hour (Gaieski 2010).
Less is known about the impact of the bundles on patients who develop sepsis on the medicine and surgical wards of the hospital. One of the major problems is that there is often a delay in recognition of the sepsis syndrome. That’s where the concept of an “early warning” system becomes important. Theoretically, earlier recognition of evolving sepsis should lead to earlier therapies and better outcomes.
Investigators at Barnes-Jewish Hospital in St. Louis have just published some preliminary results of a system of real-time computerized alerts for possible sepsis in non-ICU patients (Sawyer 2011). Through review of prior cases the same group of investigators had derived and validated a real-time computerized prediction tool (Thiel 2010). That tool contains both information from vital signs monitoring and a variety of laboratory parameters. When the prediction tool identified a patient on the medicine ward with possible sepsis, an alert was sent automatically (via text page) to the charge nurse on that ward. That nurse would then assess the patient and notify the covering physician, who would decide on any further course of action. Their results showed that patients in the intervention group were more likely to have an increased rate of interventions (such as antibiotic escalation, fluid therapy, oxygen, cultures and other diagnostic tests, etc.) within 12 hours than the nonintervention group. Though both groups had the same rate of transfer to the ICU, those in the intervention group were transferred earlier on average. However, there was no difference in mortality or total hospital length of stay between the two groups, though this pilot study was underpowered to show any such difference.
Consider this study a “proof of concept” study. It basically shows that a “smart” computerized monitoring and alerting system is capable of recognizing patients with a potentially deteriorating condition early and getting staff to respond earlier than they would otherwise. The next step obviously is to do a randomized controlled trial using similar methodology to a much larger patient population. But the idea is a good one and the number of clinical conditions to which similar methodologies might be applied is large.
The concept of “track and trigger” early warning systems is not new. In our December 29, 2009 Patient Safety Tip of the Week “Recognizing Deteriorating Patients” we discussed MEWS (the modified early warning score). MEWS was a good start to the concept that monitoring multiple parameters simultaneously and integrating them to provide a “bigger picture” might be potentially valuable. MEWS began as a paper-based system but with the introduction of more sophisticated physiologic monitoring systems and more widespread us of electronic medical records, the concept of rules-based algorithms running in the background and generating alerts to clinicians has become a reality. Expect much more on such systems over the next few years but be wary of adopting them on a widespread basis before they have been shown to impact “hard” outcomes, not just process measures that are proxies of potential outcomes.
Of course, remember that the best way to reduce mortality from sepsis is to avoid sepsis in the first place! If you have good patient safety programs in place to avoid some of the hospital-acquired conditions that may serve as precursors of sepsis, such as catheter-associated UTI’s (CAUTI’s), ventilator-associated pneumonias (VAP’s), and catheter-associated bacteremias (CLABSI’s), you’ll find that your overall incidence of hospital-acquired sepsis should decrease.
Lynn LA, Curry JP. Patterns of unexpected in-hospital deaths: a root cause analysis. Patient Safety in Surgery 2011, 5:3 (11 February 2011)
Surviving Sepsis Campaign. Website.
Levy MM, Dellinger RP, Townsend SR, et al. on behalf of the Surviving Sepsis Campaign. The Surviving Sepsis Campaign: Results of an international guideline-based performance improvement program targeting severe sepsis. Critical Care Medicine 2010; 38(2): 367-374
Castellanos-Ortega A, Suberviola B, García-Astudillo, Luis A, et al. Impact of the Surviving Sepsis Campaign protocols on hospital length of stay and mortality in septic shock patients: Results of a three-year follow-up quasi-experimental study. Critical Care Medicine 2010; 38(4): 1036-1043
Gaieski DF, Mikkelsen ME, Band RA, et al. Impact of time to antibiotics on survival in patients with severe sepsis or septic shock in whom early goal-directed therapy was initiated in the emergency department. Crit Care Med 2010; 38(4): 1045-53
Sawyer AM., Deal EN, Labelle AJ, et al. Implementation of a real-time computerized sepsis alert in nonintensive care unit patients. Critical Care Medicine 2011; 39(3): 469-473