Monitoring of cardiovascular physiology augmented by a patient-specific biomechanical model during general anesthesia. A proof of concept study

• Published in: PloS one Vol. 15; no. 5; p. e0232830
• Main Authors: Le Gall, Arthur, Vallée, Fabrice, Pushparajah, Kuberan, Hussain, Tarique, Mebazaa, Alexandre, Chapelle, Dominique, Gayat, Étienne, Chabiniok, Radomír
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 14.05.2020; Public Library of Science (PLoS)
• Subjects: Algorithms; Anesthesia; Anesthesia, General - methods; Anesthesiology; Aorta; Arterial Pressure - physiology; Bioengineering; Biology and Life Sciences; Biomechanical Phenomena; Biomechanics; Biomedical engineering; Blood Pressure; Cardiac Output - physiology; Cardiology and cardiovascular system; Cardiovascular physiology; Catheters; Complexity; Computer simulation; Coronary vessels; Data collection; Echocardiography; Ethics; Exclusion zones; Female; General anesthesia; Heart; Heart rate; Hemodynamic monitoring; Hemodynamic Monitoring - methods; Hemodynamics; Hospitals; Human health and pathology; Humans; Hypotension; Hypotension - drug therapy; Hypotension - physiopathology; Indicators; Intensive care; Intensive care units; Intubation; Life Sciences; Magnetic resonance imaging; Male; Measurement methods; Mechanical properties; Medical research; Medicine and Health Sciences; Methods; Middle Aged; Models, Cardiovascular; Monitoring; Muscle contraction; Norepinephrine; Norepinephrine - administration & dosage; Observational studies; Patients; Physical Sciences; Physiology; Precision medicine; Proof of Concept Study; Prospective Studies; Research and Analysis Methods; Stroke; Stroke volume; Stroke Volume - physiology; Vasoconstrictor Agents - administration & dosage; Ventricle; Waveforms; France; United Kingdom > UK; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0232830

During general anesthesia (GA), direct analysis of arterial pressure or aortic flow waveforms may be inconclusive in complex situations. Patient-specific biomechanical models, based on data obtained during GA and capable to perform fast simulations of cardiac cycles, have the potential to augment hemodynamic monitoring. Such models allow to simulate Pressure-Volume (PV) loops and estimate functional indicators of cardiovascular (CV) system, e.g. ventricular-arterial coupling (Vva), cardiac efficiency (CE) or myocardial contractility, evolving throughout GA. In this prospective observational study, we created patient-specific biomechanical models of heart and vasculature of a reduced geometric complexity for n = 45 patients undergoing GA, while using transthoracic echocardiography and aortic pressure and flow signals acquired in the beginning of GA (baseline condition). If intraoperative hypotension (IOH) appeared, diluted norepinephrine (NOR) was administered and the model readjusted according to the measured aortic pressure and flow signals. Such patients were a posteriori assigned into a so-called hypotensive group. The accuracy of simulated mean aortic pressure (MAP) and stroke volume (SV) at baseline were in accordance with the guidelines for the validation of new devices or reference measurement methods in all patients. After NOR administration in the hypotensive group, the percentage of concordance with 10% exclusion zone between measurement and simulation was >95% for both MAP and SV. The modeling results showed a decreased Vva (0.64±0.37 vs 0.88±0.43; p = 0.039) and an increased CE (0.8±0.1 vs 0.73±0.11; p = 0.042) in hypotensive vs normotensive patients. Furthermore, Vva increased by 92±101%, CE decreased by 13±11% (p < 0.001 for both) and contractility increased by 14±11% (p = 0.002) in the hypotensive group post-NOR administration. In this work we demonstrated the application of fast-running patient-specific biophysical models to estimate PV loops and functional indicators of CV system using clinical data available during GA. The work paves the way for model-augmented hemodynamic monitoring at operating theatres or intensive care units to enhance the information on patient-specific physiology.