Blood Pressure Estimation Using Explainable Deep-Learning Models Based on Photoplethysmography.

Background: Due to their invasiveness, arterial lines are not typically used in routine monitoring, despite their superior responsiveness in hemodynamic monitoring and detecting intraoperative hypotension. To address this issue, noninvasive, continuous arterial pressure monitoring is necessary. We developed a deep-learning model that reconstructs continuous mean arterial pressure (MAP) using the photoplethysmograhy (PPG) signal and compared it to the arterial line gold standard.

Design of a pharmacokinetic/pharmacodynamic model for administration of low dose peripheral norepinephrine during general anaesthesia.

Aims: Intraoperative hypotension is a risk factor for kidney, heart and cognitive postoperative complications. Literature suggests that the use of low-dose peripheral norepinephrine (NOR) reduces organ dysfunction, yet its administration remains unstandardized. In this work we develop a pharmacokinetic (PK)/pharmacodynamic (PD) model of NOR and its effect on mean arterial pressure (MAP).

Association of velocity-pressure loop-derived values recorded during neurosurgical procedures with postoperative organ failure biomarkers: a retrospective single-center study.

Background: Perioperative renal and myocardial protection primarily depends on preoperative prediction tools, along with intraoperative optimization of cardiac output (CO) and mean arterial pressure (MAP). We hypothesise that monitoring the intraoperative global afterload angle (GALA), a proxy of ventricular afterload derived from the velocity pressure (VP) loop, could better predict changes in postoperative biomarkers than the recommended traditional MAP and CO.

Method: This retrospective monocentric study included patients programmed for neurosurgery with continuous VP loop monitoring.

Impact of supporting nanometric membranes on the thermo-optical dynamics of individual plasmonic nanodisks.

The thermal dynamics and transient optical response of individual gold nanodisks supported on thin silicon nitride membranes were investigated using optical time-resolved pump-probe spectroscopy and finite-element modeling. The effect of reducing the membrane thickness from 50 nm to 15 nm on the nanodisk thermal dynamics was explored. A significant deceleration of the nanodisk cooling kinetics was observed, and linked to a quasi-two-dimensional heat diffusion process within the 15 nm thick membrane, without detectable modification of its thermal conductivity.

Micro- and macrocirculatory effects of norepinephrine on anaesthesia-induced hypotension: a prospective preliminary study.

Background: Intraoperative arterial hypotension (IOH) leads to increased postoperative morbidity. Norepinephrine is often use to treat IOH. The question regarding the mode of administration in either a bolus or continuous infusion remains unanswered.