Surveillance and monitoring each represent a distinct process in patient care. Monitoring involves observation, measurement, and recording of physiological parameters, while surveillance is a systematic, goal-directed process based on early detection of signs of change, interpretation of the clinical implications of such changes, and initiation of rapid, appropriate interventions.
Through use of an illustrative clinical example based on Early Warning System scoring and rapid response teams, this article seeks to distinguish between nurse monitoring and surveillance to demonstrate the impact of surveillance on improving both care processes and patient care.
Using a clinical example, differences between surveillance and monitoring as a trigger for deployment of the rapid response team were reviewed. The use of surveillance versus monitoring resulted in a mean reduction in rapid response team deployment time of 291 minutes. The median hospital length of stay for patients whose clinical care included using surveillance to initiate the deployment of the rapid response team was reduced by 4 days.
Monitoring relies on observation and assessment while nursing surveillance incorporates monitoring with recognition and interpretation of the clinical implications of changes to guide decisions about subsequent actions. The clinical example described here supports that the use of an automated surveillance system versus monitoring had a measurable impact on clinical care.
Hospital leadership must establish, implement, and oversee standards of care and continually re-evaluate care processes in order to provide high-quality care for more diverse and high-acuity-level patient populations. Strategies to improve the quality of care, prevent or reduce adverse events, and ensure equitable access to quality care include the use of computerized decision support systems, improved measurement and reporting efforts, and the increased use of patient monitoring and surveillance.1 Surveillance improves patient care through appropriate assessment, interpretation, and use of information to guide individualized care management.1 The appropriate use of surveillance can provide an important foundation for improving the quality of patient care and reducing avoidable medical errors.
Avoidable medical errors and adverse events of varying severity are estimated to cause more than 1 million patient injuries2 and tens of thousands of deaths2–6 annually. Adverse events affect nearly one in seven inpatients in the United States7 and result in more deaths than breast cancer or acquired immunodeficiency syndrome.5 Analysis of a nationally representative random sample of Medicare beneficiaries revealed that 13.5% of hospitalized patients have experienced an adverse event. That is equivalent to 134,000 patients affected by a serious error each month. An additional 13.5% of Medicare beneficiaries experienced events resulting in temporary harm that required medical intervention with almost one-half of medical errors deemed preventable.7
The rates of preventable adverse events and the quality of healthcare vary by geographic region,8–11 healthcare system,12–14 and patient populations,13,15–20 with diverse factors contributing to these variations. Patients experience more complex health problems and are at higher risk of becoming seriously ill while hospitalized.21 Furthermore, patients once considered medically fragile are undergoing complex surgical and medical interventions, which places them at greater risk for adverse events.22 There is an increased need for higher-acuity inpatient beds with ward nurses to care for patients who previously would be admitted to critical or intensive care units (ICUs).23 The mix of nursing skills, nurse-to-patient ratios, and bed shortages also affect quality of care.22,24
This article seeks to clarify the distinctions between patient monitoring and surveillance and to discuss the unique roles of surveillance and monitoring in patient care with a focus on the strengths and limitations of each process. The potential impact of nursing surveillance on patient safety and clinical outcomes is illustrated using a case example based on Early Warning System (EWS) scoring and rapid response teams and systems (RRTSs).
Surveillance Versus Monitoring in Clinical Care
Various terms describe the work of nurses in the identification of clinical changes indicative of clinically relevant changes in a patient's condition.22,25 Florence Nightingale was among the first to associate monitoring with nursing care. She described monitoring as a patient observation with the goal of data collection to save lives, prevent harm, and improve outcomes. This description was refined to “an assessment process in which clinicians observe, measure, and record patient data.”26,27 Perhaps the most obvious example of monitoring is the assessment of patient vital signs, which is a nursing function performed for more than 100 years28 and initially focused on five parameters: temperature, respiration rate, oxygen saturation, blood pressure, and heart rate.28 The list of essential vital signs was recently expanded to include monitoring levels of consciousness, pain, and urine output.22,29
Nurses rely on vital sign assessment to monitor patients and identify unfavorable changes in their clinical condition, often before observing objective evidence of deterioration. Surveillance combines patient monitoring with active observation, analysis of information, and interpretation of relevant findings.30–34 Failure to monitor and process observed information contributes to poor clinical management, including delays to diagnosis, treatment, or referral; suboptimal assessment; and inadequate or inappropriate management. Such compromises in care can carry serious consequences, including admission to critical care units, cardiac arrest, prolongation of hospital stay, and death.35–37 Recent data support that failures in both monitoring and surveillance are the primary root cause of unplanned ICU admissions.38 Surveillance can be distinguished from monitoring by its purpose, approach, data sources, and analysis (Table 1).
All hospitalized patients require some level of manual or automated monitoring.
Monitoring does not include the cognitive, analytic, and decision-making skills that are essential elements of clinical surveillance.39 Patient monitoring is a crucial element but not the only aspect of surveillance. Monitoring primarily focuses on observing, measuring, and recording physiological parameters. All hospitalized patients require some level of manual or automated monitoring.40 Surveillance is more appropriately applied to patients for whom monitoring provides data indicative of changes in clinical status and who need further evaluation and possible intervention. Three monitoring domains are associated with nursing surveillance: diagnostic monitoring, therapeutic monitoring, and monitoring to manage rapidly changing clinical situations.39
Routine patient monitoring is an increasingly important strategy for detecting subtle changes in a patient's status to ensure appropriate interventions are implemented before those changes evolve into a serious event. Monitoring is a continuous and comparative process of patient care, which includes an evaluation component that distinguishes it from simple patient observation.40 Nurses compare data obtained through monitoring with previously collected information and normative values. This comparative evaluation facilitates recognition of potential complications and changes in clinical status. Nurses routinely monitor vital signs and assess clinical status, with or without the assistance of automated machines, at intervals based on illness severity.41 However, monitoring does not integrate the analytic and decision-making skills that are essential elements of nursing surveillance.27
Surveillance is a systematic and goal-directed process focused on the early detection of the signs of deterioration, recognition of changes, and initiation of rapid and appropriate interventions.27,42 More specifically, surveillance includes evaluation of monitoring parameters plus the acquisition, integration, and interpretation of information from other sources, including family members, other members of the healthcare team, medical databases, and clinical decision support systems.26,42,43 The essential components of nurse surveillance include ongoing observation, recognition, interpretation, and decision making (Figure 1).44
Ongoing observation includes physical and mental examinations, identification of changes in physiological, cognitive or behavioral status,45 and evaluation of laboratory findings, medications, adverse effects, and drug interactions.26,42 Observed changes in the patient's status are interpreted as evidence of increasing risk or a desired response to medical interventions.44
Recognition is the ability to identify patient conditions that deviate from baseline measurements, normative standards, or parameters of interest established at the time of the initial patient assessment. Informative indicators of changes in patient status include vital signs, neurological and mental status, cardiac and respiratory functioning, and laboratory results.44
Interpretation logically follows observation and recognition of changes in patient status. It requires that nurses synthesize information within the context of individual patients and their environment while relying upon critical thinking, experience, and clinical judgement.42,44
Decision making, the final component of surveillance, requires that nurses decide to continue monitoring or take actions in response to observed change(s) in the patient's status. Such actions can include modifications to the care plan, communication with other members of the healthcare team, and mobilization of resources to address emerging clinical needs.42,44
When performed properly, surveillance allows nurses to identify patients at risk for unfavorable clinical outcomes and potential adverse events, as well as to interrupt and correct medical errors. Nurses interpret information within the full context of the patient's physical, emotional, and mental status and share it with all members of the care team.
Importantly, surveillance is a repeated, regular, and ongoing process conducted by multiple nurses as they monitor their patient's condition around the clock.42,44 When performed within the overall context of all patient variables, surveillance may improve early identification of patients who are at risk for unexpected deterioration, which can prevent serious complications, adverse events, medical errors, and death.42
Example of Nursing Surveillance: Early Warning Systems
The deterioration of patients outside the critical care unit usually presents as a progressive physiologic decline over several hours rather than occurring as a sudden onset.46–51 Patients frequently exhibit physiologic signs of instability in the respiratory, cardiovascular, and/or neurological systems, which can be measured by routine monitoring. This may result in serious deterioration, which clinicians could have recognized and treated earlier if they used surveillance to assess and interpret data provided by routine monitoring at the onset.46–51
Patients receiving care in low-acuity areas are monitored intermittently according to individual hospital practices and standards. This can result in overlooking changes in physiologic status that provide an early indication of imminent and potentially preventable serious adverse events (e.g., an in-hospital cardiac arrest).46–51 A retrospective evaluation of the association between the number of abnormal vital signs and in-hospital mortality demonstrated that 59.4% of patients experienced at least one abnormal vital sign 1 to 4 hours before experiencing an in-hospital cardiac arrest and 13.4% experienced one or more severely abnormal vital sign. Mortality rates increased as the number (odds ratio 1.53 [95% CI 1.42–1.64]) and severity (1.62 [1.38–1.90]) of pre-arrest abnormal vital signs rose.35
Surveillance may improve early identification of patients who are at risk of deterioration, which can prevent complications, adverse events, medical errors, and death.
Rapid Response Teams and Systems
Missed opportunities for early intervention based on changes in monitored vital signs and patient status are the impetus for development and implementation of RRTSs. An RRTS consists of a group of clinicians who can be deployed at any time to bring critical care expertise to patients at any hospital location, ensuring timely delivery of appropriate treatment and prevention of patient deterioration. The RRTS model was implemented in diverse healthcare systems, including Australia, Canada, the United Kingdom, and the United States.52–55
RRTSs and automated alerts of declines in clinical status are associated with lower hospital mortality, fewer cardiopulmonary arrests, reductions in non–critical care unit cardiac arrests and unplanned ICU transfers, and decreased hospital length of stay.52,53,55–58 RRTSs are also associated with reduced rates of cardiac arrest prior to transfer to ICUs,59 reduced incidence of cardiopulmonary arrests,60 increased survival immediately after RRTS treatment, and increased survival to discharge.54 A meta-analysis reported that RRTSs significantly reduced in-hospital mortality rates in adult (risk ratio 0.87 [95% CI 0.8–0.95], P < 0.001) and pediatric (0.82 [0.76–0.89]) inpatient populations. Cardiopulmonary arrests in adult (0.65 [0.61–0.70]) and pediatric (0.64 [0.55–0.74]) general ward patients were also significantly reduced.55 Importantly, delays in RRTS activation were independently associated with increased rates of patient mortality and unfavorable morbidity outcomes.61
Early Warning System scores do not predict outcomes or direct clinicians' actions. Rather, the scores indicate that patients may be deteriorating and in need of clinical intervention.
Early Warning Systems
The optimal use of RRTSs requires quantitative criteria to guide patient assessment for deterioration and trigger timely interventions. Various iterations of EWS scoring were developed to more reliably identify at-risk patients and trigger appropriate clinical interventions.62 Such systems are based on the premise that physiological changes detected by a combination of various parameters provide a more comprehensive clinical picture of patient deterioration or instability compared with changes in any single parameter.
Although hospitals vary in their exact methods for calculating EWS scores and triggering the RRTS, the typical physiologic parameters include heart rate, respiratory rate, blood pressure, temperature, and urine output. EWS typically generates RRTS trigger scores by allocating points to a list of physiologic parameters based on deviations from accepted “normal” ranges. The score for each parameter is summed, which yields a composite score that estimates a patient's level of risk for an unfavorable outcome. When the total exceeds a prespecified value, RRTS members are alerted to a potentially deteriorating condition.
Importantly, EWS scores do not predict outcomes or direct clinicians' actions. Rather, the scores indicate that patients may be deteriorating and in need of clinical interventions and/or additional surveillance. As nurses work to achieve early identification of patients at risk for deterioration, monitoring provides the data source for EWS scoring. Surveillance of monitored data triggers interventions to prevent or treat patient deterioration before the situation becomes life threatening. Nursing staff compile the patient's clinical picture and initiate actions or continue monitoring and care based on their interpretation of EWS scores.
Surveillance Versus Monitoring
A total of 157 inpatients admitted to two general medical-surgical wards in a large teaching hospital were evaluated. RRTSs were the standard of care for all patients, with criteria for activating the team shown in Table 2.
The criteria consisted primarily of vital signs monitored by nurses or nursing assistants as part of routine patient care. An EWS score of 2 prompted initiation of additional monitoring and surveillance while scores of 3 or greater resulted in calls to the RRTS to provide further patient evaluation and treatment (Figure 2). All patients in the sample reported EWS scores that triggered RRTS calls.
In the 87 patients where the EWS score was manually calculated, vital signs were collected intermittently and manually. The EWS score was calculated manually based on each set of vital signs, with the total score determining subsequent actions. This method of patient assessment relied primarily on monitoring but not surveillance. The nurses or nursing assistants obtained and recorded patient vital signs. However, the monitored vital signs were not consistently evaluated against prior measurements or institutional standards at the time of assessment.
Vital signs were also collected intermittently in the 70 patients where care was provided using surveillance. However, the automated system was integrated with the patient monitors used to obtain vital signs. Calculation of EWS scores was performed automatically each time vital signs were taken, which allowed ongoing and automatic comparisons with previous vital signs. In addition, visible alerts were provided at the point of care whenever the combination of vital signs resulted in a score that met or exceeded the criteria for alerting the RRTS. This method of assessment required nurses to interpret visible alerts and make a determination about the need for RRTS intervention as soon as the vital signs were taken. This met the criteria of observation, recognition, interpretation, and decision making, which are essential to nursing surveillance.
A review of basic patient demographics found no differences in the clinical acuity, medical/surgical case mix, age, gender, or number of vital signs taken between the patients who were cared for using surveillance versus monitoring. The mean time for nurses to call the RRTS for the patients using surveillance was 152 minutes, and the mean time for patients using monitoring only was 443 minutes. In addition, median hospital length of stay for patients in the EWS group using monitoring was 14 days compared with 10 days for patients who were cared for using surveillance.
Nursing surveillance is a complex, multidimensional process with the potential to optimize patient management, reduce treatment delays, and improve safety. The hallmark of nursing surveillance is “purposeful and ongoing acquisition, interpretation, and synthesis of patient data [to support] clinical decision making.”40 Monitoring is more than simple patient observation. It incorporates evaluation and use of different methods to collect and accumulate patient data and compare these data to standard values. Monitoring is an essential element of surveillance. However, monitoring alone does not incorporate data analysis, interpretation, and decision-making skills, all of which are essential elements of surveillance.
Clinical surveillance is based on the premise that there is no single measure or measurement method in patient care. Surveillance requires the ability to perceive and recognize relationships and similarities in multiple clinical measures and identify threats and risks to the patient's well-being. Surveillance also requires more intense participation by caregivers. A vast array of technologies are both available and under development for use in surveillance. Thus, improvements in patient safety require an organizational commitment to invest in technologies and care processes that can support surveillance.63
A systemwide approach to clinical surveillance promotes awareness of safety within an organization and encourages all caregivers to assume proactive roles in the interpretation of data collected through monitoring. Daily opportunities exist for learning as data is recognized, interpreted, and acted upon countless times for multiple patients during a single shift. Successful surveillance requires ongoing training to ensure an understanding of systems, develop the ability to identify threats, identify clinical triggers, and contribute to efforts to improve clinical care and safety. The reliability of surveillance activities and systems must be evaluated and improved continuously to achieve meaningful and sustained improvements in patient safety and clinical outcomes in an efficient and cost-effective manner.63
Successful surveillance requires ongoing training to ensure an understanding of systems, develop the ability to idenfity threats, identify clinical triggers, and contribute to efforts to improve clinical care and safety.
The clinical example described here highlights differences in the clinical values of surveillance versus monitoring. The most relevant difference was that the automated EWS supported surveillance by providing each patient's score for real-time evaluation by nursing staff. This prompted actions immediately following vital sign monitoring for each patient, resulting in a shorter time-to-treatment. These findings are consistent with recent data, which found that implementing a Modified Early-Warning Scoring (MEWS) system without a clear surveillance protocol was associated with only 1% of patients having a correctly documented MEWS score and delayed recognition of patient deterioration.38
Conclusion and Implications for Future Research
Monitoring is characterized by ongoing patient observation and assessment. Nursing surveillance uses the results of monitoring to recognize changes in the patient's clinical status, interpret the clinical implications of these changes, and decide if actions are required. The case example supports the use of an automated surveillance system to improve care. Future research should focus on the implementation and evaluation of technology and processes that can facilitate the use of surveillance in acute care settings.
Medical writing support was provided by Carole Alison Chrvala, PhD, of Health Matters, Inc.
Funding and Disclosure
Financial support for manuscript development and writing was provided by Medtronic. The author performed this work as a consultant for Medtronic.
The data used in this study was approved for use by the Institutional Review Board at Orlando Regional Medical Center, Orlando, FL.
About the Author
Karen K. Giuliano, RN, PhD, FAAN, is a nurse scientist at Hallmark Health in Medford, MA. Email: firstname.lastname@example.org