Abnormal vital signs during recovery from noncardiac surgery on general wards

BACKGROUND: In patients recovering from noncardiac surgery on general wards, the duration and severity of postoperative vital sign abnormalities remain largely unknown. OBJECTIVES: To quantify abnormal vital signs using automated continuous monitoring. DESIGN: Single-centre prospective observational study. SETTING: University Medical Center Hamburg-Eppendorf, Hamburg, Germany. PATIENTS: A total of 190 adults recovering from noncardiac surgery on general wards. INTERVENTION: Automated blinded monitoring of vital signs using a wearable device for up to 5 postoperative days. MAIN OUTCOME MEASURES: The primary outcome was the percentage of monitoring time patients had any abnormal vital sign (peripheral oxygen saturation ≤91%, respiratory rate ≤8 or ≥25 breaths per min, systolic blood pressure ≤90 or ≥220 mmHg, or pulse rate ≤40 or ≥131 beats per min). RESULTS: The median [IQR] percentage of monitoring time and the median cumulative time patients had any abnormal vital sign were 6 [3 to 12]% and 155 [58 to 375] min, respectively. 74 patients (39%) had any abnormal vital sign for at least 15 continuous minutes. The most frequently observed vital sign abnormalities were hypoxaemia and bradypnoea. Hypoxaemia occurred for a median cumulative time of 33 [7 to 123] min and lasted for at least 15 continuous minutes in 59 patients (31%). Bradypnoea occurred for a median cumulative time of 62 [17 to 159] min and lasted for at least 15 continuous minutes in 19 patients (10%). Other vital sign abnormalities were rare. CONCLUSIONS: Abnormal vital signs were common in patients recovering from noncardiac surgery on general wards. Hypoxaemia and bradypnoea were the most common vital sign abnormalities. Future research should further investigate the clinical relevance of abnormal vital signs and evaluate whether automated vital sign monitoring can facilitate early detection and timely intervention to improve patient outcomes. STUDY REGISTRATION: German Clinical Trials Register (DRKS00030284) on 6 October 2022.