Vital signs monitors are tools that can make a significant difference in postoperative patient outcomes. About half of adverse events occur in general care areas. However, acute cardiorespiratory events do not occur unexpectedly. Up to 60% of patients show one or more abnormal vital signs up to 4-6 hours before experiencing cardiac arrest. Therefore, it is crucial for healthcare professionals responsible for them to early detect changes in cardiorespiratory physiology to take preventive and/or therapeutic measures that favor a satisfactory recovery.
Hence the need for physicians and nurses to have reliable vital signs monitors that help them monitor patients without increasing their workload. This article addresses the advantages of closely monitoring patients, emphasizing the benefits of trend analysis of their vital signs to prevent fatal outcomes.
Furthermore, episodes of respiratory depression have been reported in up to 46% of patients receiving opioids in general care wards, which can progress to respiratory arrest if undetected. According to the document “Preventing respiratory depression”, continuous monitoring could prevent many catastrophic respiratory events.
Limitations of Intermittent Vital Signs Monitoring in Postoperative Care
Generally, in hospital wards, nurses check patients’ vital signs with several hours between each check (approximately every 2 to 4 hours). Due to the intermittent nature of these checks, there is a risk of overlooking abnormalities in vital signs that typically precede serious adverse events.
The study by Zhuo Sun et al., titled “Postoperative hypoxemia is common and persistent: A prospective blinded observational study”, noted that when nurses check vital signs every 4 hours, they may miss up to 90% of hypoxemia events.
Similarly, “Incidence, severity, and detection of blood pressure perturbations after abdominal surgery: A prospective blinded observational study” states that this practice also leads to the failure to detect approximately 50% of hypotensive events. Other studies suggest that intermittent monitoring of patients’ vital signs is a key factor contributing to failure in rescue efforts. Therefore, other authors conclude that continuous monitoring of vital signs could help improve postoperative outcomes.
Furthermore, episodes of respiratory depression have been reported in up to 46% of patients receiving opioids in general care wards, which can progress to respiratory arrest if undetected. According to the document “Preventing respiratory depression”, continuous monitoring could prevent many catastrophic respiratory events.
Continuous Postoperative Vital Signs Monitoring and Trend Analysis
Continuous monitoring can undoubtedly be very beneficial in all hospital areas, as many in-hospital cardiac arrests occur in general or medical wards. An audit conducted in 144 hospitals across the UK reported in-hospital cardiac arrests in 23,554 adult patients. Many of these events were observed in medical patients (over 80%) and occurred in the wards (57%).
The issue is that many patients do not deteriorate unexpectedly; rather, healthcare professionals suddenly notice their deteriorating condition. A study compared the Modified Early Warning Score (based on the aggregation of vital signs) in ward patients who did or did not have a cardiac arrest. The Modified Early Warning Score was significantly different not only 30 minutes before but also 8, 24, and even up to 48 hours before the arrest, despite both groups having the same Modified Early Warning Score at the time of ward admission.
Other studies have shown that vital signs often exhibit abnormalities hours before cardiac arrest or ICU admission. These studies highlight the fact that clinical deterioration is often progressive. Therefore, continuous monitoring, with a focus on trend analysis of patients’ vital signs, can help detect abnormal clinical trajectories at an early stage and could reduce the number of severe adverse events.
Critical Vital Signs for Detecting Postoperative Clinical Deterioration
Early warning scores combining various vital signs are better predictors of severe adverse events than individual vital signs alone. Thanks to connectivity advancements, there are now vital signs monitors that automatically calculate trends, providing healthcare professionals with a comprehensive view of the patient’s condition. Some of the vital signs that carry significant weight in outcomes include:
Heart Rate and Continuous ECG Monitoring in Postoperative Patients
During the postoperative period, heart rate (HR) can increase due to various factors such as stress, pain, atrial fibrillation, sepsis, and bleeding. Increased HR is not a specific marker but an indicator of clinical deterioration. In a cohort study conducted in 360 hospitals in the United States by Lyons et al., abnormal heart rate was responsible for 21.6% of 402,023 rapid response team activations. Continuous electrocardiographic monitoring also benefits patients. According to the document “The International Surgical Outcomes Study group. Global patient outcomes after elective surgery: Prospective cohort study in 27 low-, middle-, and high-income countries”, cardiac arrhythmia was the third most common postoperative complication.
Postoperative Blood Pressure Monitoring and Hypotension Risk
Monitoring blood pressure allows for detection of both hypertensive and hypotensive events. While the impact of postoperative hypertension has not been confirmed, data indicate that postoperative hypotension is associated with adverse events such as acute kidney injury, myocardial infarction, and death. The study by Lyons et al. reports that hypotension accounted for 15.7% of rapid response team activations.
Oxygen Saturation Monitoring and Early Detection of Respiratory Complications
The study by Lyons et al. also mentions that a decrease in SpO2 was responsible for 21.2% of rapid response team activations. In patients receiving oxygen, SpO2 can be a late indicator of respiratory complications.
Respiratory Rate as a Key Early Indicator of Postoperative Deterioration
Respiratory rate (RR) can be abnormal in many clinical situations, including respiratory complications, sepsis, and metabolic disorders (such as acidosis). In the study by Lyons et al., out of a total of 59,720 rapid response team activations due to RR abnormalities, 71% were caused by tachypnea and 29% by bradypnea.
According to “Multicenter Comparison of Machine Learning Methods and Conventional Regression for Predicting Clinical Deterioration on the Wards”, which included over 260,000 ward patients and used machine learning methods to predict clinical deterioration, RR was a decisive factor in the predictive algorithm, followed by heart rate, systolic blood pressure, and SpOâ‚‚.
Preventable Postoperative Deaths Due to Undetected Vital Sign Changes
Unexpected deaths in hospital wards are frequent because patients’ clinical deterioration can go unnoticed for hours. This is often related to low nurse-to-patient ratios and the time intervals between routine vital sign checks. Reliable vital signs monitors can help address this challenge by improving clinical outcomes and, in turn, patient satisfaction. They also help reduce nurses’ workload and limit the costs associated with emergency interventions and potential negligence claims when adverse events occur.
Fortunately, solutions that enable continuous monitoring are available, and several studies show that their implementation is associated with fewer ICU admissions, rescue interventions, cardiac arrests, and deaths. To achieve these benefits, healthcare professionals need monitors that deliver reliable alarms, clear trend information, and remote monitoring capabilities. Devices designed with these features can meaningfully support clinical practice and enhance patient care.
Reliable Vital Signs Monitors for Continuous Patient Surveillance
SCHILLER offers easy-to-use, reliable vital signs monitoring solutions designed to support continuous patient surveillance in postoperative and general care settings. Our patient monitors help healthcare professionals detect early signs of clinical deterioration while maintaining efficient clinical workflows.
TRANQUILITY II Patient Monitor
The TRANQUILITY II patient monitor is a comprehensive monitoring system designed to collect, process, analyze, and display up to nine vital sign parameters in real time. It features a 12.1-inch color LCD touchscreen and an optional integrated printer, combining multiple monitoring capabilities in a single device.
Its compact, lightweight, and portable design, together with a built-in battery, makes the TRANQUILITY II ideal for continuous monitoring during patient transport and bedside care.
Monitored parameters include:
ECG (3- or 5-lead) and heart rate
Non-invasive blood pressure (NIBP)
Temperature
Oxygen saturation (SpO₂ – Digital or Masimo)
Respiratory rate
The Tranquility II also features the Central View function. It connects 4 to 32 Tranquility II monitors through wired or wireless networking. This setup allows healthcare teams to monitor multiple patients simultaneously from the nurses’ station. It improves patient visibility, shortens response times, and streamlines clinical workflows. The Central View function offers all the advantages shown in the following image:
TRANQUILITY VS Vital Signs Monitor
The TRANQUILITY VS vital signs monitor is designed for efficient and reliable monitoring of essential vital signs in adult and pediatric patients. This compact system continuously measures and displays up to three key parameters, making it well suited for postoperative wards and general care units.
Monitored parameters include:
Non-invasive blood pressure (systolic, diastolic, and mean arterial pressure)
Oxygen saturation (SpOâ‚‚)
End-tidal COâ‚‚ (EtCOâ‚‚)
Discover how SCHILLER vital signs monitors support early detection of patient deterioration, improve postoperative outcomes, and reduce clinical workload. Watch the videos to learn more about our patient monitoring solutions and how they can be integrated into your clinical environment.
To explore how these solutions can meet your specific needs, click the button below to request a personalized, free demo.
Sources of this article
[1] Bernd Saugel et al. Automated Continuous Noninvasive Ward Monitoring: Validation of Measurement Systems Is the Real Challenge. Anesthesiology. March 2020, Vol. 132, 407–410. DOI: https://doi.org/10.1097/ALN.0000000000003100
[2] Frederic Michard et al. Rethinking Patient Surveillance on Hospital Wards. Anesthesiology September 2021, Vol. 135, 531–540. https://doi.org/10.1097/ALN.0000000000003843
[3] Zhuo Sun et al. Postoperative Hypoxemia Is Common and Persistent: A Prospective Blinded Observational Study. Anesth Analg.2015 Sep;121(3):709-715. doi: 10.1213/ANE.0000000000000836Â
[4] Alparslan Turan et al. Incidence, Severity, and Detection of Blood Pressure Perturbations after Abdominal Surgery: A Prospective Blinded Observational Study. Anesthesiology. 2019 Apr;130(4):550-559. DOI: 10.1097/ALN.0000000000002626Â
[5] Daryl A Jones. Rapid-response teams. N Engl J Med. 2011 Jul 14;365(2):139-46. DOI: 10.1056/NEJMra0910926Â
[6] John P Abenstein, Bradly J Narr. An ounce of prevention may equate to a pound of cure: can early detection and intervention prevent adverse events? Anesthesiology. 2010 Feb;112(2):272-3. DOI: 10.1097/ALN.0b013e3181ca858dÂ
[7] Daniel Sessler Preventing respiratory depression. Anesthesiology. 2015 Mar;122(3):484-5. DOI: 10.1097/ALN.0000000000000565Â
[8] Patrick G Lyons et al. Characteristics of Rapid Response Calls in the United States: An Analysis of the First 402,023 Adult Cases From the Get With the Guidelines Resuscitation-Medical Emergency Team Registry. Crit Care Med. 2019 Oct;47(10):1283-1289. DOI: 10.1097/CCM.0000000000003912
[9] The International Surgical Outcomes Study group. Global patient outcomes after elective surgery: Prospective cohort study in 27 low-, middle-, and high-income countries. Br J Anaesth. 2016 Oct 31;117(5):601-609. DOI: 10.1093/bja/aew316Â
[10] Matthew M Churpek et al. Multicenter Comparison of Machine Learning Methods and Conventional Regression for Predicting Clinical Deterioration on the Wards. Crit Care Med. 2016 Feb;44(2):368-74. DOI: 10.1097/CCM.0000000000001571
Frequently Asked Questions About Postoperative Vital Signs Monitoring
What is postoperative vital signs monitoring?
Postoperative vital signs monitoring refers to the systematic measurement and analysis of key physiological parameters—such as heart rate, blood pressure, oxygen saturation, and respiratory rate—after surgery. Its primary purpose is to detect early signs of clinical deterioration and prevent adverse events in hospital wards.
Why is continuous vital signs monitoring important after surgery?
Continuous vital signs monitoring is important because postoperative deterioration often develops gradually rather than suddenly. Abnormal trends in vital signs can appear hours before serious events such as cardiac arrest, respiratory failure, or unplanned ICU admission, allowing for earlier intervention.
How does continuous monitoring differ from intermittent vital signs checks?
Intermittent monitoring captures patient data only at scheduled intervals, which increases the risk of missing transient or progressive abnormalities. In contrast, continuous monitoring provides real-time data and trend analysis, improving the detection of physiological changes that may precede clinical deterioration.
Which vital signs are most important for detecting postoperative deterioration?
The most critical vital signs include heart rate and ECG, blood pressure, oxygen saturation (SpOâ‚‚), and respiratory rate. When analyzed together using trend data or early warning scores, these parameters are more predictive of adverse events than any single vital sign alone.
Can continuous vital signs monitoring reduce ICU admissions and in-hospital mortality?
Yes. Multiple studies have shown that continuous monitoring in general care wards is associated with fewer rescue interventions, reduced ICU admissions, lower rates of in-hospital cardiac arrest, and decreased postoperative mortality by enabling earlier clinical response.
How does trend analysis improve patient safety in hospital wards?
Trend analysis allows healthcare professionals to identify gradual changes in a patient’s condition over time rather than relying on isolated measurements. This approach supports earlier recognition of deterioration, more timely interventions, and improved clinical decision-making.
What features should a vital signs monitor have for postoperative care?
Vital signs monitors used in postoperative settings should provide reliable alarms, continuous data acquisition, trend visualization, and remote or centralized monitoring capabilities. These features help clinicians respond quickly while reducing workflow burden.
How do centralized monitoring systems support nursing staff?
Centralized monitoring systems allow multiple patients to be observed simultaneously from a nurses’ station. This improves situational awareness, reduces the need for frequent bedside checks, and helps nurses prioritize care based on real-time patient data.
Are SCHILLER vital signs monitors suitable for general care wards?
Yes. SCHILLER vital signs monitors are designed for use in postoperative and general care wards, offering continuous monitoring, trend analysis, and connectivity options that support early detection of patient deterioration and efficient clinical workflows.