Congenital Diaphragmatic Hernia (CDH) consists in an incomplete foetal development of the diaphragm during gestation, leading to pulmonary hypoplasia and hypertension at birth. A current prenatal management strategy to restore proper lung development is to occlude the foetal airway through the endoscopic insertion of a plastic balloon (Foetal Endoscopic Tracheal Occlusion, FETO) and reverse the occlusion by removing it with a second surgery after 8 weeks. Some studies explored the use of a biodegradable material as occluding device to avoid the second surgery and to promote lung fluid efflux by dynamic occlusion. A pilot study was carried out on an animal model of CDH at the University of Western Australia to test effectiveness of FETO procedures using a novel hydrogel developed at Politecnico di Milano. The aim of this project is the design and development of an ultra-low power implantable device to monitor both the average pressure developed in the lung and the pressure oscillations due to foetal breathing efforts while the tracheal occlusion is in place. The device includes flash memory for data logging and a wireless RF telemetry system, allowing real-time monitoring during in-utero foetal development. The device was enclosed in a biocompatible case with catheters for pressure sensing, and implanted for 40 days during the pilot study. Wireless communication and storage functionalities resulted to be effective. However, battery life was lower than expected, with a median duration of 15 days. A design revision was performed to improve power retention capability. The data collected during the device operative period proved the possibility to monitor pressure and identify foetal breathing. The provided data also allowed the re-design of the experimental protocol. The revised device was tested in vitro showing the successful overcome of the limitations identified during the pilot and will be used for a study on the efficacy of the new FETO treatment.
L’ernia diaframmatica congenita (Congenital Diaphragmatic Hernia, CDH) consiste in un incompleto sviluppo fetale del diaframma e porta ad ipoplasia ed ipertensione polmonare del nascituro. Il corretto sviluppo polmonare può essere ripristinato mediante l’occlusione della trachea con l’inserzione in fetoscopia di un palloncino (Foetal Endoscopic Tracheal Occlusion, FETO) seguita da un secondo intervento di rimozione dopo 8 settimane. Alcuni studi hanno esplorato l’uso di materiali biodegradabili per l’occlusione al fine di evitare il secondo intervento, e l’uso di un’occlusione dinamica per promuovere l’efflusso di fluido polmonare. Uno studio pilota è stato condotto su modello animale di CDH all’University of Western Australia per testare l’efficacia della FETO con un nuovo idrogel sviluppato al Politecnico di Milano. L’obiettivo di questa tesi è lo sviluppo di un dispositivo elettronico impiantabile low-power per monitorare la pressione media sviluppata nei polmoni durante il periodo di occlusione, e le oscillazioni pressorie dovute ai tentativi di respirazione fetale. Il dispositivo include una memoria flash per il salvataggio dei dati ed e un sistema di telemetria wireless via radio per permettere il monitoraggio in tempo reale durante lo sviluppo gestazionale. Il dispositivo è stato incapsulato in un involucro biocompatibile con dei cateteri per la misura della pressione, ed impiantato per 40 giorni nello studio pilota. La comunicazione e il salvataggio dei dati hanno funzionato correttamente. Tuttavia, la durata della batteria è risultata minore di quella attesa, con una mediana di 15 giorni. Una revisione del dispositivo è stata proposta per migliorare il risparmio energetico. I dati raccolti hanno dimostrato la possibilità di monitorare la pressione e di identificare il respiro del feto, suggerendo revisioni del protocollo sperimentale. Test in vitro sul dispositivo revisionato hanno mostrato il superamento dei limiti riscontrati nello studio pilota. Esso verrà quindi utilizzato per uno studio di efficacia del nuovo trattamento FETO.
An implantable device for monitoring foetal lung pressure in an experimental model of congenital diaphragmatic hernia
TARANTINI, FRANCESCO;ROSSI, ALESSANDRO
2017/2018
Abstract
Congenital Diaphragmatic Hernia (CDH) consists in an incomplete foetal development of the diaphragm during gestation, leading to pulmonary hypoplasia and hypertension at birth. A current prenatal management strategy to restore proper lung development is to occlude the foetal airway through the endoscopic insertion of a plastic balloon (Foetal Endoscopic Tracheal Occlusion, FETO) and reverse the occlusion by removing it with a second surgery after 8 weeks. Some studies explored the use of a biodegradable material as occluding device to avoid the second surgery and to promote lung fluid efflux by dynamic occlusion. A pilot study was carried out on an animal model of CDH at the University of Western Australia to test effectiveness of FETO procedures using a novel hydrogel developed at Politecnico di Milano. The aim of this project is the design and development of an ultra-low power implantable device to monitor both the average pressure developed in the lung and the pressure oscillations due to foetal breathing efforts while the tracheal occlusion is in place. The device includes flash memory for data logging and a wireless RF telemetry system, allowing real-time monitoring during in-utero foetal development. The device was enclosed in a biocompatible case with catheters for pressure sensing, and implanted for 40 days during the pilot study. Wireless communication and storage functionalities resulted to be effective. However, battery life was lower than expected, with a median duration of 15 days. A design revision was performed to improve power retention capability. The data collected during the device operative period proved the possibility to monitor pressure and identify foetal breathing. The provided data also allowed the re-design of the experimental protocol. The revised device was tested in vitro showing the successful overcome of the limitations identified during the pilot and will be used for a study on the efficacy of the new FETO treatment.| File | Dimensione | Formato | |
|---|---|---|---|
|
2019_04_Rossi_Tarantini.pdf
non accessibile
Descrizione: Testo della tesi
Dimensione
5.05 MB
Formato
Adobe PDF
|
5.05 MB | Adobe PDF | Visualizza/Apri |
I documenti in POLITesi sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/10589/146194