Development and validation of a feedback device suitable for resuscitation of premature neonates.

Date
2016-12
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: Neonatal cardiopulmonary resuscitation (NCPR) is an important life-saving intervention. Clinicians follow the guidelines which recommend using the two-thumb (TT) or two-finger (TF) method to compress the neonates’ chest to one-third of their anterior-posterior diameter (APD) at a 3:1 compression to ventilation ratio. Ineffective compressions can result in an increased mortality and morbidity rate for neonates. Clinicians have difficulty delivering effective and consistent chest compressions (CCs) during NCPR due to the high number of actions (120 events per minute), the lack of practice due to the limited number of occurrences and poor fidelity of infant training manikins in replication of infant thoracic properties. There is therefore a need for a tool to assist the clinician in performing correct and consistent CCs. This report presents the design, fabrication and implementation of a diagnostic tool to guide the clinician on the CC rate using a metronome and on the compression depth using LED feedback. The device is battery powered and records the depth and force during CC for post processing. The need for such a device was investigated during this project by recruiting an experienced neonatal resuscitation programme (NRP) certified clinician to perform tests on five, 6-month old white New Zealand rabbits (weight = 2.74 ± 0.27 kg, APD = 88.4 ± 2.7 mm). The fidelity of the CCs during these tests was assessed according to the target depth (one-third of the APD) and according to the estimated target depth range for ‘wet’ neonates (17.5 to 22.5 mm). The results from the target depth fidelity analysis show that 97%, 2% and <1% of the CCs were too shallow, correct and too deep, respectively for all CCs according to target depth. The results for the target depth range for ‘wet’ neonates’ fidelity analysis showed that 79%, 17% and 4% of all compressions were too shallow, correct and too deep, respectively. The analysis was also performed for individual CC segments which are defined as three consecutive compressions. A segment is deemed to be correct if two out of the three compressions are within the target depth range. The segment fidelity using one-third APD was 89%, 10% and <1% for too shallow, correct and too deep, respectively. These results prove that the clinician is finding it difficult to meet the target depth and that a large percentage of the CCs are too shallow (ineffective CC) according to the APD and ‘wet’ neonate range. The segment analysis also shows that the CCs are inconsistent and very few consecutive CCs are correct and within the target range. The inconsistent and ineffective compressions performed by an experienced and trained clinician validate the need for a NCPR feedback tool for ‘wet’ neonates. A force-depth analysis was completed and the effect of the compression and ventilation method was examined. The mean force results showed no clear difference between compression methods, however, the mean depth for the TT method was higher than that of the TF method. The compression method used also affected the force-deformation curve. The ventilation method, however, had no effect on the measured CC depth and force or shape of the force-deformation curve. A key finding of this study is the ineffective and inconsistent compressions performed by an experienced and trained clinician. The CCs were mostly too shallow regardless of the compression or ventilation method. It is also clear that there is no real, significant, difference between the TT and TF method with regards to fidelity or effectiveness (compression depth and force relationship).
AFRIKAANSE OPSOMMING: Neonatale kardiopulmonêre resussitasie (NKPR) is ’n belangrike lewensreddende intervensie. Geneeshere volg die riglyne wat aanbeveel dat die twee-duim (“two-thumb” (TT)) of twee-vinger (“two-finger” (TF)) metode gebruik word om pasgeborenes se borskas te druk tot een-derde van die anterior-posterior deursnee (APD) teen ’n 3:1 drukking tot ventilasie verhouding. Oneffektiewe drukking kan lei tot verhoogde mortaliteits- en morbiditeitskoerse vir pasgeborenes. Geneeshere sukkel om effektiewe en konstante borsdrukke te gee tydens NKPR a.g.v. die hoë getal drukke wat gegee moet word (120 per minuut), die gebrek aan oefening a.g.v. die beperkte aantal kere wat dit nodig is en ook die swak getrouheid tot die werklikheid van baba oefenmodelle se toraks-eienskappe. Daar is dus ’n soeke na ’n manier om die geneeshere te help om borsdrukke reg en konstant toe te pas. Hierdie verslag stel die ontwerp, vervaardiging en implementasie voor van ’n diagnostiese instrument om die geneesheer te lei deur die gebruik van ’n metronoom vir die druktempo en LED terugvoer vir die drukdiepte. Die instrument is battery-aangedrewe en registreer die diepte en krag van die drukke vir verwerking na die tyd. Die behoefte vir so ’n instrument is ondersoek tydens hierdie projek deur ’n ervare neonatale resussitasie-program (NRP) gesertifiseerde geneesheer te werf om toetse op vyf 6-maande oue wit Nieu-Seeland konyne (gewig = 2.74 ± 0.27 kg, APD = 88.4 ± 2.7 mm) uit te voer. Die getrouheid van die borsdrukke is tydens hierdie toetse geassesseer volgens die teiken-diepte (een derde APD) en ook volgens die geskatte omvang van “nat” pasgeborenes (17.5 tot 22.5 mm). Die resultate van die teiken-diepte getrouheids-analise wys dat 97 %, 2% en <1% van die borsdrukke onderskeidelik te vlak, korrek en te diep was vir alle borsdrukke volgens teiken-diepte. Die resultate vir die omvang van “nat” pasgeborenes se getrouheids-analise het onderskeidelik gewys dat 79%, 17% en 4% van alle borsdrukke te vlak, korrek en te diep was. Die analise is ook uitgevoer vir individuele borsdruk-segmente wat gedefinieer is as drie agtereenvolgende drukke. ’n Segment is as korrek beskou as twee van die drie drukke binne die teiken-diepte was. Die segment-getrouheid volgens die een derde APD was onderskeidelik 89%, 10% en <1% te vlak, korrek en te diep. Die resultate wys dat die geneesheer dit moeilik vind om die teiken-diepte te haal en dat ’n groot persentasie van die drukke te vlak is (oneffektiewe borsdrukke) volgens die APD en “nat” pasgeborenes-omvang. Die segment-analise wys ook dat die borsdrukke inkonsekwent is en dat baie min opeenvolgende borsdrukke korrek en binne die teiken-omvang is. Die inkonsekwente en oneffektiewe borsdrukke wat uitgevoer word deur ’n ervare en opgeleide geneesheer toon dat daar ‘n behoefte is vir ’n NKPR-terugvoer instrument vir “nat” pasgeborenes. ’n Krag-diepte analise is uitgevoer en die effek van die borsdrukke en die ventilasie-metode is ondersoek. Die gemiddelde krag-resultate het geen duidelike verskil gewys tussen druk-metodes nie, maar die gemiddelde diepte van die TT-metode was hoër as dié van die TF-metode. Die druk-metode wat gebruik word beïnvloed ook die krag-vervormingskurwe. Die ventilasie-metode het egter geen effek op die krag, diepte of vorm van die krag-vervormingskurwe nie. ’n Belangrike bevinding van die projek is die oneffektiewe en inkonsekwente drukke uitgevoer deur ’n ervare en gesertifiseerde geneesheer. Die borsdrukke was meestal te vlak, ongeag die druk- of ventilasie-metode. Dit is duidelik dat daar geen werklike, beduidende verskil is tussen die TT-metode en TF-metode met betrekking tot die getrouheid of effektiwiteit (druk diepte en krag verhouding) nie.
Description
Thesis (MEng)--Stellenbosch University, 2016.
Keywords
CPR (First aid), Premature babies -- Resuscitation, Cardiopulmonary resuscitation, UCTD
Citation