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The human nasal cavity develops from birth with size anatomical changes. This study aims to evaluate the flow parameters and particle deposition parameters. Neonatal and infant nasal cavities are developed using MIMICS 21.0, and the flow is evaluated by ANSYS 2021 R2 using CFD to evaluate velocity, pressure, micro- and nanoparticle depositions under sedentary breathing conditions. Neonatal nasal valve velocity was recorded 3.5 times higher compared to the infant for 1.8 LPM and 2.7 times for 3 LPM. Neonatal vestibular depositions up to 10 µm were 6.6%, which increased to 76% for 60 µm for 1.8 LPM and increased to 21.3% for 10 µm and 79% for 60 µm for 1.8 LPM. The neonatal nasal valve showed maximum depositions of around 35% for 20 µm for both flow rates. Maximum depositions of nanoparticles are in the mid-nasal region. Infant nasal cavities deposit around 1% to 2% for nanoparticles below 20 nm for both flow rates. Neonatal overall microparticle depositions doubled with an increase in flow rate up to 10 µm. The overall deposition efficiency of nanoparticles increases 1.5 times with increasing flow rate. This study will help with the medical administration of aerosol-based medications in the patient and age-specific nasal cavity. [ABSTRACT FROM AUTHOR]

Objective: The nasal cavity effectively captures the particles present in inhaled air, thereby preventing harmful and toxic pollutants from reaching the lungs. This filtering ability of the nasal cavity can be effectively utilized for targeted nasal drug delivery applications. This study aims to understand the particle deposition patterns in three age groups: neonate, infant, and adult. Materials and methods: The CT scans are built using MIMICS 21.0, followed by CATIA V6 to generate a patient-specific airway model. Fluid flow is simulated using ANSYS FLUENT 2021 R2. Spherical monodisperse microparticles ranging from 2 to 60 µm and a density of 1100 kg/m3 are simulated at steady-state and sedentary inspiration conditions. Results: The highest nasal valve depositions for the neonate are 25% for 20 µm, for infants, 10% for 50 µm, 15% for adults, and 15% for 15 µm. At mid nasal region, deposition of 15% for 20 µm is observed for infant and 8% for neonate and adult nasal cavities at a particle size of 10 and 20 µm, respectively. The highest particle deposition at the olfactory region is about 2.7% for the adult nasal cavity for 20 µm, and it is <1% for neonate and infant nasal cavities. Discussion and conclusions: The study of preferred nasal depositions during natural sedentary breathing conditions is utilized to determine the size that allows medication particles to be targeted to specific nose regions. [ABSTRACT FROM AUTHOR]

The continuous monitoring of arterial blood pressure (BP) is vital for assessing and treating cardiovascular instability in a sick infant. Currently, invasive catheters are inserted into an artery to monitor critically-ill infants. Catheterization requires skill, is time consuming, prone to complications, and often painful. Herein, we report on the feasibility and accuracy of a non-invasive, wearable device that is easy to place and operate and continuously monitors BP without the need for external calibration. The device uses capacitive sensors to acquire pulse waveform measurements from the wrist and/or foot of preterm and term infants. Systolic, diastolic, and mean arterial pressures are inferred from the recorded pulse waveform data using algorithms trained using artificial neural network (ANN) techniques. The sensor-derived, continuous, non-invasive BP data were compared with corresponding invasive arterial line (IAL) data from 81 infants with a wide variety of pathologies to conclude that inferred BP values meet FDA-level accuracy requirements for these critically ill, yet normotensive term and preterm infants. [ABSTRACT FROM AUTHOR]