Murray Hinder

Murray Hinder
The University of Sydney · Westmead Clinical School

(PhD) Electronics Engineering/Clinical Engineer/Research Officer

About

53
Publications
6,421
Reads
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450
Citations
Additional affiliations
June 2011 - present
Westmead Hospital
Position
  • Research Officer
June 2006 - June 2011
Nepean Hospital
Position
  • Biomedical Technical Officer

Publications

Publications (53)
Preprint
PurposeIn neonatal resuscitation, using a T-piece resuscitator (TPR) is used widely, however the evidence is limited for the use in infants born at term gestation. The aim of this study was to compare the positive end expiratory pressure (PEEP) and respiratory system resistance ( R rs) using TPR and self-inflating bag (SIB) in a cadaveric piglet mo...
Preprint
Purpose: Newborn mask ventilation technique requires skills, and effective resuscitation is essential for pulmonary gas exchange. The most effective compression to ventilation (C:V) ratio in newborn resuscitation is still contentious and there is no evidence of human data supporting the current 3:1 ratio. We aimed to study mask leak and respiratory...
Book
Full-text available
The use of manual or mechanical devices to provide assisted breathing to infants can be a lifesaving and life-changing event, whether during emergency resuscitation or longer-term respiratory support. Mortality in this group is largely due to respiratory failure, complicated by cascading lung injury induced by this intervention. Research on mitigat...
Preprint
Abdominal auscultation is a convenient, safe and inexpensive method to assess bowel conditions, which is essential in neonatal care. It helps early detection of neonatal bowel dysfunctions and allows timely intervention. This paper presents a neonatal bowel sound detection method to assist the auscultation. Specifically, a Convolutional Neural Netw...
Article
Full-text available
Background: Resuscitation of infants using T-piece resuscitators (TPR) allow positive pressure ventilation with positive end-expiratory pressure (PEEP). The adjustable PEEP valve adds resistance to expiration and could contribute to inadvertent PEEP. The study indirectly investigated risk of inadvertent peep by determining expiratory time constants...
Article
Objectives: To evaluate cerebral oxygenation (cTOI) and cerebral perfusion in preterm infants in supine versus prone positions. Study design: Sixty preterm infants, born before 32 weeks gestation, were enrolled; 30 had bronchopulmonary dysplasia (BPD, defined as the need for respiratory support and/or supplemental oxygen at 36 weeks post menstru...
Article
Infant resuscitation devices used at birth must be capable of delivering adequate and consistent ventilation in a controlled and predictable manner to a wide patient weight range, and combinations of transitional lung states. Manual inflation resuscitation devices delivering positive pressure lung inflation at birth can be classified broadly into t...
Article
This is an Australia New Zealand Neonatal Network (ANZNN) wide survey to identify current practice and guide future practice improvement for the use of laryngeal mask airway (LMA) during neonatal resuscitation. An online questionnaire containing 13 questions was sent out to all tertiary neonatal centres (n = 29 units) and neonatal transport units (...
Article
Background T-piece resuscitators (TPRs) are used for primary newborn resuscitation in birthing and emergency rooms worldwide. A recent study has shown spikes in peak inflation pressure (PIP) over set values with two brands of TPRs inbuilt into infant warmer/resuscitation platforms. We aimed to compare delivered ventilation between two TPR drivers w...
Article
Background and Objectives In anaemic preterm infants who receive packed red blood cell (PRBC) transfusions, changes to mesenteric tissue oxygenation and perfusion have been reported using a restrictive haemoglobin (Hb)‐based threshold. We aimed to investigate changes to hepatic tissue oxygenation and abdominal blood flow after PRBC transfusion and...
Article
Background Very low birthweight or preterm infants are at increased risk of adverse outcomes including sepsis, necrotising enterocolitis, and death. We assessed whether supplementing the enteral diet of very low-birthweight infants with lactoferrin, an antimicrobial protein, reduces all-cause mortality or major morbidity. Methods We did a multicen...
Article
Aim: The use of umbilical arterial catheters (UACs) is a standard of care in monitoring critically unwell infants. Serious vascular complications are rare but when they do occur, they can be associated with significant morbidity, risking limb loss or even death. Near infra-red spectroscopy has the potential to monitor limb perfusion. Our study inv...
Article
Background: Red blood cell (RBC) transfusion is a standard treatment for anemia of prematurity. Cerebral tissue oxygenation and blood flow velocities improve when a restrictive transfusion threshold is followed, but little is known about the effect of practicing a liberal transfusion threshold on cerebral tissue oxygenation, cerebral blood flow ve...
Article
Aim To evaluate cerebral autoregulation changes in preterm infants receiving a loading dose of caffeine base. Methods In a cohort of 30 preterm infants, we extracted measures of cerebral autoregulation using time and frequency domain techniques to determine the correlation between mean arterial pressure (MAP) and tissue oxygenation index (TOI) sig...
Article
Full-text available
Aim A controlled bench test was undertaken to determine the performance variability among a range of neonatal self-inflating bags (SIB) compliant with current International Standards Organisation (ISO). Introduction Use of SIB to provide positive pressure ventilation during newborn resuscitation is a common emergency procedure. The United Nations...
Article
Full-text available
Introduction This review acquaints neonatal clinicians using point‐of‐care ultrasound with a range of pathological bowel ultrasound findings, with the aim to promote utility of this skill as a diagnostic assessment tool in diseased neonatal intestinal states. Overview A range of normal and pathological bowel ultrasound findings are illustrated wit...
Article
Background: The T-piece resuscitator (TPR) has seen increased use as a primary resuscitation device with newborns. Traditional TPR design uses a high resistance expiratory valve to produce PEEP/CPAP. A new TPR device which uses a dual flow ratio valve (fluidic flip) to produce PEEP/CPAP at resuscitation is now available (rPAP). We aimed to compare...
Article
Aim To evaluate the acute effect of intravenous caffeine on heart rate and blood pressure variability in preterm infants. Methods We extracted and compared linear and non‐linear features of heart rate and blood pressure variability at two timepoints: prior to and in the two hours following a loading dose of 10 mg/kg caffeine base. Results We stud...
Article
Management and monitoring of infants within the neonatal intensive care unit (NICU) represents a unique challenge. It involves an array of life-threatening diseases, procedures with potentially lifelong impacts, co-morbidities associated with preterm birth and risk of infection from prolonged exposure to the hospital environment. With the integrati...
Article
Background International neonatal resuscitation guidelines recommend the use of laryngeal mask airway (LMA) with newborn infants (≥34 weeks’ gestation or >2 kg weight) when bag-mask ventilation (BMV) or tracheal intubation is unsuccessful. Previous publications do not allow broad LMA device comparison. Objective To compare delivered ventilation of...
Article
Aim: The aim of this study was to compare mask leak with three different peak inspiratory pressure (PIP) settings during T-piece resuscitator (TPR; Neopuff) mask ventilation on a neonatal manikin model. Methods: Participants were neonatal unit staff members. They were instructed to provide mask ventilation with a TPR with three PIP settings (20,...
Article
Full-text available
Despite the decline in mortality rates of extremely preterm infants, intraventricular haemorrhage (IVH) remains common in survivors. The need for resuscitation and cardiorespiratory management, particularly within the first 24 hours of life, are important factors in the incidence and timing of IVH. Variability analyses of heart rate and blood press...
Article
Background: Manual resuscitation devices for infants and newborns must be able to provide adequate ventilation in a safe and consistent manner across a wide range of patient sizes (0.5-10 kg) and differing clinical states. There are little comparative data assessing biomechanical performance of common infant manual resuscitation devices across the...
Article
Background The T-piece resuscitator (TPR) is in common use worldwide to deliver positive pressure ventilation during resuscitation of infants <10 kg. Ease of use, ability to provide positive end-expiratory pressure (PEEP), availability of devices inbuilt into resuscitaires and cheaper disposable options have increased its popularity as a first-line...
Article
Neonatal endotracheal intubation is commonly accompanied by significant disturbances in physiological parameters. The procedure is often poorly tolerated, and multiple attempts are commonly required before the airway is secured. Adverse physiological effects include hypoxemia, bradycardia, hypertension, elevation in intracranial pressure and possib...
Article
Full-text available
Background: Non-invasive continuous positive airways pressure is commonly a primary respiratory therapy delivered via multi-purpose ventilators in premature newborns. Expiratory limb occlusion due to water accumulation or 'rainout' from gas humidification is a frequent issue. A case of expiratory limb occlusion due to rainout causing unexpected an...
Article
Background The self-inflating bag (SIB) is the most common device used to resuscitate newborn infants worldwide. Delivering positive end-expiratory pressure (PEEP) may be important in infant resuscitation and limited research using one brand (Laerdal) SIB has led to international guidelines stating SIBs ‘often deliver inconsistent positive end-expi...
Article
Full-text available
To determine changes in respiratory mechanics when chest compressions are added to mask ventilation, as recommended by the International Liaison Committee On Resuscitation (ILCOR) guidelines for newborn infants. Using a Laerdal Advanced Life Support leak-free baby manikin and a 240 mL self-inflating bag, 58 neonatal staff members were randomly pair...
Conference Paper
Full-text available
Methods Abstract Objectives Results Conclusions The primary aim of this study was to compare these devices with in terms of their effect on PEEP and Raw normally compliant (equivalent to term gestation) and poorly compliant lungs (preterm gestation) T-piece device is widely used to deliver PEEP in preterm infants and increasingly being used for ter...
Article
Full-text available
This study investigated whether arterial blood pressure waveform analysis could be useful for estimating left ventricular outflow (LVO) and total peripheral resistance (TPR) in preterm infants. A cohort of 27 infants were studied, with 89 measurements of left ventricular outflow (LVO) using Doppler echocardiography and arterial pressure using cathe...
Article
Full-text available
Very preterm infants are at high risk of death and serious permanent brain damage, as occurs with intraventricular hemorrhage (IVH). Detrended fluctuation analysis (DFA) that quantifies the fractal correlation properties of physiological signals has been proposed as a potential method for clinical risk assessment. This study examined whether DFA of...
Conference Paper
This study investigated whether arterial blood pressure waveform analysis could be useful for estimating left ventricular outflow (LVO) and total peripheral resistance (TPR) in preterm infants. A cohort of 27 infants were studied, with 89 measurements of left ventricular outflow (LVO) using Doppler echocardiography and arterial pressure using cathe...
Article
Full-text available
Frequency spectrum analysis of circulatory signals has been proposed as a potential method for clinical risk assessment of preterm infants by previous studies. In this study, we examined the relationships between various spectral measures derived from systemic and cerebral cardiovascular variabilities and the clinical risk index for babies (CRIB II...
Article
Full-text available
Near-infrared spectroscopy (NIRS) for cerebral circulation monitoring has gained popularity in the neonatal intensive care setting, with studies showing the possibility of identifying preterm infants with intraventricular hemorrhage (IVH) by transfer function analysis of arterial blood pressure (BP) and NIRS measures. In this study, we examined a n...
Article
Full-text available
Little is known regarding the variations in effective ventilation during bag and mask resuscitation with standard methods compared with that delivered by ventilator-delivered mask ventilation (VDMV). To measure the variations in delivered airway pressure, tidal volume (TV), minute ventilation (MV) and inspiratory time during a 3-min period of mask...
Article
Near-infrared spectroscopy (NIRS) for cerebral circulation monitoring has gained popularity in the neonatal intensive care setting, with studies showing the possibility of identifying preterm infants with intraventricular hemorrhage (IVH) by transfer function analysis of arterial blood pressure (BP) and NIRS measures. In this study, we examined a n...
Conference Paper
Near-infrared spectroscopy (NIRS) for cerebral circulation monitoring has gained popularity in the neonatal intensive care setting, with studies showing the possibility of identifying preterm infants with intraventricular hemorrhage (IVH) by transfer function analysis of arterial blood pressure (BP) and NIRS measures. In this study, we examined a n...
Article
Full-text available
To compare a new two-person method (four hands) of delivering mask ventilation with a standard one-person method using the Laerdal self-inflating bag (SIB) and the Neopuff (NP) infant resuscitator in a manikin model. Recent studies of simulated neonatal resuscitation using bag and mask ventilation techniques have shown facemask leak levels of 55-57...
Article
The aim of the study is to assess the effects of an intravenous 10 mg/kg loading dose of caffeine base in cerebral oxygenation, cerebral Doppler blood flow velocity and cardiac output in preterm infants. Preterm neonates <34 weeks gestation were investigated at 1 and 4 h following the loading dose of caffeine using Doppler cerebral sonography, card...
Article
Full-text available
The aim of the study is to compare mask leak and delivered ventilation during Neopuff (NP) mask ventilation in two modes: (i) with NP pressure dial hidden and resuscitator watching chest wall (CW) rise with, (ii) CW movement hidden and resuscitator watching NP pressure dial. Thirty-six participants gave mask ventilation to a modified manikin design...
Article
Very preterm infants are at high risk of death and serious permanent brain damage, as occurs with intraventricular hemorrhage (IVH). Detrended fluctuation analysis (DFA) that quantifies the fractal correlation properties of physiological signals has been proposed as a potential method for clinical risk assessment. This study examined whether DFA of...
Article
Full-text available
To assess effects of anesthesia and opioids, we studied 13 children with obstructive sleep apnea (OSA, age 4.0 +/- 2.2 yr, mean +/- SD) and 24 age-matched control subjects (5.8 +/- 4.0 yr). Apnea indexes of children with OSA were 29.4 +/- 18 h-1, median 30 h-1. Under inhalational anesthetic, closing pressure at the mask was 2.2 +/- 6.9 vs. -14.7 +/...
Article
Ventilatory responses in children with obstructive sleep apnoea (OSA) are apparently normal, but concern remains about respiratory compromise in children with OSA during the peri-operative period of adenotonsillectomy. Methods: Upper airway closing pressures were measured after anaesthetic induction, and ventilatory response to CO2 were measured af...

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Project (1)
Project
The use of manual or mechanical devices to provide assisted breathing to infants can be a lifesaving and life-changing event, whether during emergency resuscitation or longer-term respiratory support. Mortality in this group is largely due to respiratory failure, complicated by cascading lung injury induced by this intervention. Research on mitigating injury by differing methods and technologies of breathing support is mostly focused on preterm infant weights < 2kg and in a limited range of devices. The objective of this thesis is to examine the biomechanical performance of different types and brands of infant ventilation devices across the wide weight range (~450gms to 10kg), and lung physiology/disease states that they are required to perform. The role of International Standards and medical device regulators in informing manufacturers about minimum safety and performance were also examined, as these are integral to the capacity of devices to deliver safe ventilation to the cohort. A range of devices was tested with experienced clinicians simulating resuscitation using manikin and bench test lung models. Results revealed inherent design flaws, poor performance, and critical safety issues in some of the most common devices used worldwide to ventilate infants. Serious shortcomings in the International Standards relating to the basic safety and performance characteristics for infant ventilation were exposed. Reliance by medical device regulatory authorities on compliance with these standards as an indication of an efficacious device is ill-advised. Inadequacies in ventilation device design or their clinical application, often undetectable to the user, can cause lifelong respiratory and neurodevelopmental complications. Future development of improved device testing models encompassed in revised International Standards will have a real impact in reducing poor outcomes after receiving this lifesaving intervention.