Technical realization of a sensorized neonatal intubation skill trainer for operators' retraining and a pilot study for its validation.

BACKGROUND: In neonatal endotracheal intubation, excessive pressure on soft tissues during laryngoscopy can determine permanent injury. Low-fidelity skill trainers do not give valid feedback about this issue. This study describes the technical realization and validation of an active neonatal intubation skill trainer providing objective feedback. METHODS: We studied expert health professionals' performances in neonatal intubation, underlining chance for procedure retraining. We identified the most critical points in epiglottis and dental arches and fixed commercial force sensors on chosen points on a ©Laerdal Neonatal Intubation Trainer. Our skill trainer was set up as a grade 3 on Cormack and Lehane's scale, i.e. a model of difficult intubation. An associated software provided real time sound feedback if pressure during laryngoscopy exceeded an established threshold. Pressure data were recorded in a database, for subsequent analysis with non-parametric statistical tests. We organized our study in two intubation sessions (5 attempts each one) for everyone of our participants, held 24 h apart. Between the two sessions, a debriefing phase took place. In addition, we gave our participants two interview, one at the beginning and one at the end of the study, to get information about our subjects and to have feedback about our design. RESULTS: We obtained statistical significant differences between consecutive attempts, with evidence of learning trends. Pressure on critical points was significantly lower during the second session (p < 0.0001). Epiglottis' sensor was the most stressed (p < 0.000001). We found a significant correlation between time spent for each attempt and pressures applied to the airways in the two sessions, more significant in the second one (shorter attempts with less pressure, rs = 0.603). CONCLUSIONS: Our skill trainer represents a reliable model of difficult intubation. Our results show its potential to optimize procedures related to the control of trauma risk and to improve personnel retraining.

An active simulator for neonatal intubation: Design, development and assessment.

This study describes the technical realization and the pre-clinical validation of a instrumented neonatal intubation skill trainer able to provide objective feedback for the improvement of clinical competences required for such a delicate procedure. The Laerdal® Neonatal Intubation Trainer was modified by applying pressure sensors on areas that are mainly subject to stress and potential injuries. Punctual Force Sensing Resistors (FSRs) were characterized and fixed on the external side of the airway structure on the dental arches and epiglottis. A custom silicone tongue was designed and developed to integrate a matrix textile sensor for mapping the pressure applied on its whole surface. The assessment of the developed tool was performed by nine clinical experts who were asked to practice three intubation procedures apiece. Median and maximum forces, over threshold events (i.e. 2N for gingival arch sensors and 7N for epiglottis and tongue sensors respectively) and execution time were measured for each trainee. Data analysis from training sessions revealed that the epiglottis is the point mainly stressed during an intubation procedure (maximum value: 16.69N, median value: 3.11N), while the analysis carried out on the pressure distribution on the instrumented tongue provided information on both force values and distribution, according to clinicians' performance. The debriefing phase was used to enhance the clinicians' awareness of applied force and gestures performed, confirming that the present study is an adequate starting point for achieving and optimizing neonatal intubation skills for both residents and expert clinicians.

Pressure mapping with textile sensors for compression therapy monitoring.

Compression therapy is the cornerstone of treatment in the case of venous leg ulcers. The therapy outcome is strictly dependent on the pressure distribution produced by bandages along the lower limb length. To date, pressure monitoring has been carried out using sensors that present considerable drawbacks, such as single point instead of distributed sensing, no shape conformability, bulkiness and constraints on patient's movements. In this work, matrix textile sensing technologies were explored in terms of their ability to measure the sub-bandage pressure with a suitable temporal and spatial resolution. A multilayered textile matrix based on a piezoresistive sensing principle was developed, calibrated and tested with human subjects, with the aim of assessing real-time distributed pressure sensing at the skin/bandage interface. Experimental tests were carried out on three healthy volunteers, using two different bandage types, from among those most commonly used. Such tests allowed the trends of pressure distribution to be evaluated over time, both at rest and during daily life activities. Results revealed that the proposed device enables the dynamic assessment of compression mapping, with a suitable spatial and temporal resolution (20 mm and 10 Hz, respectively). In addition, the sensor is flexible and conformable, thus well accepted by the patient. Overall, this study demonstrates the adequacy of the proposed piezoresistive textile sensor for the real-time monitoring of bandage-based therapeutic treatments.

A novel simulator for mechanical ventilation in newborns: MEchatronic REspiratory System SImulator for Neonatal Applications.

Respiratory problems are among the main causes of mortality for preterm newborns with pulmonary diseases; mechanical ventilation provides standard care, but long-term complications are still largely reported. In this framework, continuous medical education is mandatory to correctly manage assistance devices. However, commercially available neonatal respiratory simulators are rarely suitable for representing anatomical and physiological conditions; a step toward high-fidelity simulation, therefore, is essential for nurses and neonatologists to acquire the practice needed without any risk. An innovative multi-compartmental infant respirator simulator based on a five-lobe model was developed to reproduce different physio-pathological conditions in infants and to simulate many different kinds of clinical scenarios. The work consisted of three phases: (1) a theoretical study and modeling phase, (2) a prototyping phase, and (3) testing of the simulation software during training courses. The neonatal pulmonary simulator produced allows the replication and evaluation of different mechanical ventilation modalities in infants suffering from many different kinds of respiratory physio-pathological conditions. In particular, the system provides variable compliances for each lobe in an independent manner and different resistance levels for the airway branches; moreover, it allows the trainer to simulate both autonomous and mechanically assisted respiratory cycles in newborns. The developed and tested simulator is a significant contribution to the field of medical simulation in neonatology, as it makes it possible to choose the best ventilation strategy and to perform fully aware management of ventilation parameters.

Comparative performances analysis of neonatal ventilators.

BACKGROUND: Mechanical ventilation is a therapeutic action for newborns with respiratory diseases but may have side effects. Correct equipment knowledge and training may limit human errors. We aimed to test different neonatal mechanical ventilators' performances by an acquisition module (a commercial pressure sensor plus an isolated chamber and a dedicated software). METHODS: The differences (ΔP) between peak pressure values and end-expiration pressure were investigated for each ventilator. We focused on discrepancies among measured and imposed pressure data. A statistical analysis was performed. RESULTS: We investigated the measured/imposed ΔP relation. The ΔP do not reveal univocal trends related to ventilation setting parameters and the data distributions were non-Gaussian. CONCLUSIONS: Measured ΔP represent a significant parameter in newborns' ventilation, due to the typical small volumes. The investigated ventilators showed different tendencies. Therefore, a deep specific knowledge of the intensive care devices is mandatory for caregivers to correctly exploit their operating principles.

Sensorized toys for measuring manipulation capabilities of infants at home.

Preterm infants, i.e. babies born after a gestation period shorter than 37 weeks, spend less time exploring objects. The quantitative measurement of grasping actions and forces in infants can give insights on their typical or atypical motor development. The aim of this work was to test a new tool, a kit of sensorized toys, to longitudinally measure, monitor and promote preterm infants manipulation capabilities with a purposive training in an ecological environment. This study presents preliminary analysis of grasping activity. Three preterm infants performed 4 weeks of daily training at home. Sensorized toys with embedded pressure sensors were used as part of the training to allow quantitative analysis of grasping (pressure and acceleration applied to toys while playing). Each toy was placed on the midline, while the infant was in supine position. Preliminary data show differences in the grasping parameters in relation to infants age and the performed daily training. Ongoing clinical trial will allow a full validation of this new tool for promoting object exploration in preterm infants.

An active one-lobe pulmonary simulator with compliance control for medical training in neonatal mechanical ventilation.

Mechanical ventilation is a current support therapy for newborns affected by respiratory diseases. However, several side effects have been observed after treatment, making it mandatory for physicians to determine more suitable approaches. High fidelity simulation is an efficient educational technique that recreates clinical experience. The aim of the present study is the design of an innovative and versatile neonatal respiratory simulator which could be useful in training courses for physicians and nurses as for mechanical ventilation. A single chamber prototype, reproducing a pulmonary lobe both in size and function, was designed and assembled. Volume and pressure within the chamber can be tuned by the operator through the device control system, in order to simulate both spontaneous and assisted breathing. An innovative software-based simulator for training neonatologists and nurses within the continuing medical education program on respiratory disease management was validated. Following the clinical needs, three friendly graphic user interfaces were implemented for simulating three different clinical scenarios (spontaneous breathing, controlled breathing and triggered/assisted ventilation modalities) thus providing physicians with an active experience. The proposed pulmonary simulator has the potential to be included in the range of computer-driven technologies used in medical training, adding novel functions and improving simulation results.

MEchatronic REspiratory System SImulator for Neonatal Applications (MERESSINA) project: a novel bioengineering goal.

Respiratory function is mandatory for extrauterine life, but is sometimes impaired in newborns due to prematurity, congenital malformations, or acquired pathologies. Mechanical ventilation is standard care, but long-term complications, such as bronchopulmonary dysplasia, are still largely reported. Therefore, continuous medical education is mandatory to correctly manage devices for assistance. Commercially available breathing function simulators are rarely suitable for the anatomical and physiological realities. The aim of this study is to develop a high-fidelity mechatronic simulator of neonatal airways and lungs for staff training and mechanical ventilator testing. The project is divided into three different phases: (1) a review study on respiratory physiology and pathophysiology and on already available single and multi-compartment models; (2) the prototyping phase; and (3) the on-field system validation.