Non‑invasive monitoring and prognostic indicators in critical conditions: from hemodynamics to metabolism (systematic review)

Introduction. Modern critical care medicine focuses on integrative real-time monitoring that combines the assessment of hemodynamics, autonomic regulation, and metabolism to enable early detection of risks and optimization of therapy. However, despite technological advances, there remains a high demand in routine intensive care practice for the systematization of information precisely on those parameters that remain amenable to rapid measurement, evaluation, and treatment adjustment during ongoing patient observation, regardless of the specific equipment available in a given hospital.

Objective. Determination of the feasibility of using non-invasive methods for assessing hemodynamics, autonomic tone, and laboratory biomarkers for prognosis and proactive risk management.

Materials and methods. This systematic review was conducted in accordance with the PRISMA 2020 guidelines. A search was performed using Google Scholar, as well as the bibliographic databases PubMed/MEDLINE, RSCI (eLIBRARY), CyberLeninka, and the ClinicalTrials.gov registry for the period 2010–2025. Original research and systematic reviews addressing non-invasive hemodynamic monitoring, assessment of the diastolic shock index (DSI), the heart-rate-to-body-temperature ratio (HR/T), as well as blood lactate levels and lactate clearance in adult patients admitted to intensive care units were included. Due to heterogeneity among the studies, a qualitative data synthesis was performed.

Discussion. Technologies of non-invasive hemodynamic monitoring (the unloaded artery method, bioreactance, thoracic bioimpedance spectroscopy) and prognostic indices were reviewed. A DSI > 2.2 mmHg/min has been shown to be an independent predictor of mortality in septic shock, particularly when used with dynamic assessment and combined with lactate levels. A HR/T > 20.5 bpm/°C reflects impaired autonomic regulation and is associated with an unfavorable outcome in sepsis, complicated infectious diseases, and heart failure. Failure to achieve lactate clearance (< 10% over 6 h) is more informative than its initial level and serves as a key metabolic marker. The greatest predictive utility is achieved through multi-parameter data integration.

Conclusions. The modern approach to monitoring in intensive care should be multidimensional and dynamic. The complementary use of non-invasive hemodynamic monitoring, simple calculated indices (DSI, HR/T), and biomarkers (lactate) enables the creation of an integrated predictive model of the patient’s condition. Promising directions for the development of monitoring include the personalization of threshold values and the integration of data into clinical decision support systems.

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