David Schell - Academia.edu (original) (raw)

Papers by David Schell

Research paper thumbnail of Delayed recognition of esophageal intubation in a neonate: Role of radiologic diagnosis

Critical Care Medicine, Dec 1, 1994

Research paper thumbnail of P0366 / #1043: A Population-Based Study of Infants and Children Admitted to Intensive Care in Australia

Pediatric Critical Care Medicine, Mar 1, 2021

Research paper thumbnail of Peri-operative management of paediatric patients undergoing cardiac surgery – focus on respiratory aspects of care

Paediatric Respiratory Reviews, Dec 1, 2007

ABSTRACT Children requiring cardiac surgery present particular challenges in peri-operative respi... more ABSTRACT Children requiring cardiac surgery present particular challenges in peri-operative respiratory management. The wide variety of conditions and operations and their varied impact on respiratory function makes dialogue with related medical staff essential. In most circumstances, cardiac performance is the main determinant of respiratory outcomes. Changing cardiologic and surgical approaches have combined to diminish the severity and frequency of pulmonary hypertensive issues and new treatment modalities are simplifying the intensive care approach. Patients with Down's syndrome and 22q11 deletion syndrome present particular issues related to anatomy, physiology and respiratory function. Certain conditions, including tetralogy of Fallot and cavopulmonary connections, present unique circumstances where respiratory management, sometimes including extubation, may assist in optimisation of cardiac performance. These and other conditions highlight the complexities of cardiopulmonary interactions. Cardiac performance remains the principal determinant of outcome after paediatric cardiac surgery and has the biggest impact on respiratory function.

Research paper thumbnail of Ontogeny of β-Adrenergic Receptors in Pulmonary Arterial Smooth Muscle, Bronchial Smooth Muscle, and Alveolar Lining Cells in the Rat

American Journal of Respiratory Cell and Molecular Biology, 1992

ABSTRACT beta-Adrenergic receptors play an integral role in the modulation of cell function in th... more ABSTRACT beta-Adrenergic receptors play an integral role in the modulation of cell function in the developing lung. In the rat, there are marked increases in beta receptor density in whole lung during postnatal maturation, but it is now known whether there are differential developmental changes in receptor density in specific cell types. Quantitative light microscopic autoradiography with [125I]iodocyanopindolol ([125I]ICYP) was used to determine maturational changes in beta-adrenergic receptor density in pulmonary arterial smooth muscle (ASM), bronchial smooth muscle (BSM), and alveolar lining cells (ALC) in rat lung during postnatal development (1 day to 6 mo). [125I]ICYP binding to whole lung sections revealed a single class of high-affinity receptors; agonist competitive binding studies suggested that the receptors are primarily of the beta 2 subtype. beta-Adrenergic receptor density in newborn (1 day) lung was lowest in ASM cells and was comparable in BSM cells and ALC. In contrast, in lungs from adult rats (3 mo), receptor density was similar in ASM versus BSM cells and was 2-fold greater in ALC. In addition, the maturational pattern of increasing receptor density differed in ASM compared with BSM and ALC. Receptor density in ASM increased 93% from 1 to 13 days, another 92% from 13 to 20 days, and was unchanged thereafter. In contrast, receptor density in BSM cells did not change from 1 to 13 days, but it increased 65% from 13 to 20 days, rose another 47% from 20 days to 3 mo, and increased an additional 24% from 3 to 6 mo.(ABSTRACT TRUNCATED AT 250 WORDS)

Research paper thumbnail of Humidified high‐flow nasal cannula oxygen in bronchiolitis reduces need for invasive ventilation but not intensive care admission

Journal of Paediatrics and Child Health, 2017

AimTo describe the changes to paediatric intensive care unit (PICU) admission patterns and ventil... more AimTo describe the changes to paediatric intensive care unit (PICU) admission patterns and ventilation requirements for children with bronchiolitis following the introduction of humidified high‐flow nasal cannula oxygen outside the PICU.MethodsRetrospective study comparing patients <24 months of age with a discharge diagnosis of bronchiolitis admitted to the PICU. A comparison was made between those before humidified high‐flow nasal cannula oxygen use (year 2008) to those immediately following the introduction of humidified high‐flow nasal cannula oxygen use (year 2011) and those following further consolidation of humidified high‐flow nasal cannula oxygen use outside the PICU (year 2013).ResultsHumidified high‐flow nasal cannula oxygen use up to 1 L/kg/min in the hospital did not reduce PICU admission. Intubation rates were reduced from 22.2% in 2008 to 7.8% in 2013. There was a non‐significant trend towards decreased length of stay in the PICU while hospital length of stay showe...

Research paper thumbnail of Association Between Centralization and Outcome for Children Admitted to Intensive Care in Australia and New Zealand: A Population-Based Cohort Study*

Pediatric Critical Care Medicine

Objectives: To describe regional differences and change over time in the degree of centralization... more Objectives: To describe regional differences and change over time in the degree of centralization of pediatric intensive care in Australia and New Zealand (ANZ) and to compare the characteristics and ICU mortality of children admitted to specialist PICUs and general ICUs (GICUs). Design: A retrospective cohort study using registry data for two epochs of ICU admissions, 2003–2005 and 2016–2018. Setting: Population-based study in ANZ. Patients: A total of 43,256 admissions of children aged younger than 16 years admitted to an ICU in ANZ were included. Infants aged younger than 28 days without cardiac conditions were excluded. Interventions: None. Measurements and Main Results: The primary outcome was risk-adjusted ICU mortality. Logistic regression was used to investigate the association of mortality with the exposure to ICU type, epoch, and their interaction. Compared with children admitted to GICUs, children admitted to PICUs were younger (median 25 vs 47 mo; p < 0.01) and stayed...

Research paper thumbnail of Factors associated with admission of children to an intensive care unit and readmission to hospital within 28 days of discharge: A population‐based study

Journal of Paediatrics and Child Health, 2021

AimHospital readmissions within 28 days are an important performance measurement of quality and s... more AimHospital readmissions within 28 days are an important performance measurement of quality and safety of health care. The aims of this study were to examine the rates, trends and characteristics of paediatric intensive care unit admissions, and factors associated with readmissions to hospital within 28 days of discharge.MethodsThis retrospective, population‐based record linkage study included all children ≥28 days and <16 years old admitted to an intensive care unit (ICU) in a New South Wales (NSW) public hospital from 2004 to 2013. Data were sourced from the NSW Admitted Patients Data Collection and the NSW Registry of Births, Deaths and Marriages, Death Registration.ResultsWe identified 21 200 ICU admissions involving 17 130 children. Admissions increased by 24% over the study period with the greatest increase attributed to respiratory and musculoskeletal conditions. A higher proportion of children were <5 years, male, lived in major cities, were publicly insured and had ch...

Research paper thumbnail of Use of forensic interview techniques to identify important handover information in post operative cardiac surgey procedures

Research paper thumbnail of A Comparison of expert and competent paediatric diagnosis

Research paper thumbnail of Inferior vena cavathrombosis asacomplication of femoral veincatheterisation

Indwelling femoral venous catheters were prospectively studied by ultrasonography to define the f... more Indwelling femoral venous catheters were prospectively studied by ultrasonography to define the frequency and evolution of inferior vena cava (IVC) thrombosis. IVC thrombosis was identified in six of 56 catheters (54 children). Only one patient with a positive ultrasound scan had clinical signs of thrombosis. All children with IVC thrombosis had had catheters in place for over six days. It is recommended that either the femoral central venous catheters are routinely changed at six days or ultrasound studies are routinely performed twice a week in all patients with catheters in situ for six or more days and that the catheter is removed immediately if evidence of thrombosis appears.

Research paper thumbnail of The Effect of Imputation of Pao 2/Fi o 2 From Spo 2/Fi o 2 on the Performance of the Pediatric Index of Mortality 3*

Pediatric Critical Care Medicine

Research paper thumbnail of Effect of post-mortem delay on density of tachykinin receptors in rat peripheral tissues

Peptides, 1998

The effect of post-mortem delay on the affinity and density of tachykinin NK 1 and NK 2 receptors... more The effect of post-mortem delay on the affinity and density of tachykinin NK 1 and NK 2 receptors was examined in the rat submandibular gland and gastric fundus, respectively, using saturation binding studies with the radioligands [ 125 I]Bolton-Hunter [Sar 9 , Met(O 2) 11 ]SP and [ 125 I][Lys 5 , Tyr(I 2) 7 , MeLeu 9 , Nle 10 ]NKA(4-10). For NK 1 receptors, no significant changes were seen in either K d (control 375 Ϯ 35 pM, n ϭ 5; 32 h post-mortem 390 Ϯ 59 pM, n ϭ 5) or B max (control 96 Ϯ 16 fmol/mg protein, n ϭ 5; 32 h post-mortem 62 Ϯ 10 fmol/mg protein, n ϭ 5). For NK 2 receptors, no alterations were seen up to 16 h post-mortem. However, significant (p Ͻ 0.001) changes were seen at 32 h post-mortem (n ϭ 4), where values for K d were increased (3.0 Ϯ 0.2 nM) and those for B max were reduced (42 Ϯ 5.9 fmol/mg protein), relative to control (K d ϭ 1.3 Ϯ 0.2 nM; B max ϭ 208 Ϯ 30 fmol/mg protein, n ϭ 5). These changes are probably related to observed histological deterioration. This study demonstrates the stability of tachykinin receptors in these peripheral tissues and indicates the suitability of post-mortem tissue as a valid control in future tachykinin receptor studies.

Research paper thumbnail of Primary immunization status of children attending the Port Moresby General Hospital

Papua and New Guinea medical journal, 1987

Research paper thumbnail of Effect of post-mortem delay on density of tachykinin receptors in rat peripheral tissues

Peptides, 1998

The effect of post-mortem delay on the affinity and density of tachykinin NK 1 and NK 2 receptors... more The effect of post-mortem delay on the affinity and density of tachykinin NK 1 and NK 2 receptors was examined in the rat submandibular gland and gastric fundus, respectively, using saturation binding studies with the radioligands [ 125 I]Bolton-Hunter [Sar 9 , Met(O 2) 11 ]SP and [ 125 I][Lys 5 , Tyr(I 2) 7 , MeLeu 9 , Nle 10 ]NKA(4-10). For NK 1 receptors, no significant changes were seen in either K d (control 375 Ϯ 35 pM, n ϭ 5; 32 h post-mortem 390 Ϯ 59 pM, n ϭ 5) or B max (control 96 Ϯ 16 fmol/mg protein, n ϭ 5; 32 h post-mortem 62 Ϯ 10 fmol/mg protein, n ϭ 5). For NK 2 receptors, no alterations were seen up to 16 h post-mortem. However, significant (p Ͻ 0.001) changes were seen at 32 h post-mortem (n ϭ 4), where values for K d were increased (3.0 Ϯ 0.2 nM) and those for B max were reduced (42 Ϯ 5.9 fmol/mg protein), relative to control (K d ϭ 1.3 Ϯ 0.2 nM; B max ϭ 208 Ϯ 30 fmol/mg protein, n ϭ 5). These changes are probably related to observed histological deterioration. This study demonstrates the stability of tachykinin receptors in these peripheral tissues and indicates the suitability of post-mortem tissue as a valid control in future tachykinin receptor studies.

Research paper thumbnail of Binding characteristics of endothelin ETA receptors in normal and post-mortem rat lung

Peptides, 2000

In control lung homogenates, optimal specific binding of [ 125 I]endothelin-1 and minimal filter ... more In control lung homogenates, optimal specific binding of [ 125 I]endothelin-1 and minimal filter binding was achieved using 50 g/ml bacitracin, 30 M phenylmethylsulphonyl fluoride (PMSF) and 10 mM EDTA. In post-mortem tissue (8, 16, and 32 h), no significant changes were seen in ET A receptor affinity (K d) or number (B max): control and 32 h K d ϭ 309 Ϯ 75, 225 Ϯ 32 pM and B max ϭ 173 Ϯ 42, 185 Ϯ 17 fmol/mg protein, respectively. Autoradiographic binding sites for [ 125 I]endothelin-1 were densely expressed on bronchiolar smooth muscle and parenchyma with moderate binding on epithelium and blood vessels. Histologic sections of post-mortem lung showed minimal deterioration of structures expressing ET A binding sites. Hence the ET A receptor is stable in the rat lung for up to 32 h post-mortem.

Research paper thumbnail of Ventilator-associated pneumonia in a tertiary paediatric intensive care unit: a 1-year prospective observational study

Critical care and resuscitation : journal of the Australasian Academy of Critical Care Medicine, 2012

To determine the incidence, risk factors and impact of ventilator-associated pneumonia (VAP) in a... more To determine the incidence, risk factors and impact of ventilator-associated pneumonia (VAP) in a mixed tertiary paediatric intensive care unit. Prospective observational study. Patients in the intensive care unit who were mechanically ventilated for more than 48 hours were assessed daily, according to criteria for a diagnosis of VAP. Potential risk factors for VAP, if present, were documented. Of 692 invasively ventilated patients, 269 (38.9%) were ventilated for > 48 hours and met no exclusion criteria. Eighteen (6.7%) patients had episodes of VAP, and the VAP incidence density was 7.02 per 1000 intubation days. The mean admission Paediatric Index of Mortality 2 risk of death was similar in patients with and without VAP (0.084 v 0.056; P =0.8). Patients with VAP (compared with patients without VAP) had a longer median duration of ICU stay, (19.35 v 7.35 days; P < 0.001), duration of ventilation (11.99 v 4.92 days; P=0.024) and duration of hospital stay (35.5 v 20 days; P &lt...

Research paper thumbnail of Use of propofol infusion in Australian and New Zealand paediatric intensive care units

Anaesthesia and intensive care

Despite the risk of propofol infusion syndrome, a rare but often fatal complication of propofol i... more Despite the risk of propofol infusion syndrome, a rare but often fatal complication of propofol infusion in ventilated children and possibly adults, propofol infusion remains in use in paediatric intensive care units (PICU). This questionnaire study surveys the current pattern of use of this sedative infusion in Australian and New Zealand PICUs. Thirty-three of the 45 paediatric intensive care physicians surveyed (73%), from 12 of the 13 intensive care units, returned completed questionnaires. The majority of practitioners (82%) use propofol infusion in children in PICU, the main indication being for short-term sedation in children requiring procedures. 39% of respondents consider propofol infusion useful in ventilated children requiring longer-term sedation. 67% of paediatric intensivists use maximum infusion doses that may be considered dangerously high (> or = 10 mg/kg/h). Nineteen per cent use propofol infusion for prolonged periods (> 72 hours). A smaller proportion (15%)...

Research paper thumbnail of Development and implementation of a feeding algorithm to optimise nutrition in Paediatric Intensive Care

Australian Critical Care, 2015

Research paper thumbnail of Congenital rubella--still with us

The Medical journal of Australia, Jan 23, 1986

Research paper thumbnail of Clonidine overdose in childhood: Implications of increased prescribing

Journal of Paediatrics and Child Health, 1998

To highlight the increase in the number of cases of clonidine overdose admitted to a specialist p... more To highlight the increase in the number of cases of clonidine overdose admitted to a specialist paediatric hospital, with particular reference to the clinical features, clinical course and circumstances surrounding the incident. Cases of clonidine overdose were identified by review of the emergency department attendance register, the intensive care unit database and inpatient statistics collection. Case notes were reviewed to determine the clinical features, history and clinical course in each case. Fifteen patients experienced 16 overdoses during the period 1990-97 inclusive. Only one case occurred before 1994. Depressed level of consciousness and bradycardia were the most common clinical manifestations, and were observed in 75 and 88% of cases respectively. There were no fatalities. Five patients received naloxone. Other treatment modalities included gastrointestinal decontamination, atropine, ventilation and inotropic support. Fourteen cases occurred in association with medication prescribed for attention-deficit hyperactivity disorder (ADHD). Clonidine overdose is a potentially serious condition, often requiring intensive care management. Our experience suggests that it is a growing problem, related in part to its increased use in the treatment of ADHD. Preventive strategies, including raising the level of awareness of risks, changes to packaging and appropriate selection of patients for treatment, need consideration if further overdoses are to be prevented.

Research paper thumbnail of Delayed recognition of esophageal intubation in a neonate: Role of radiologic diagnosis

Critical Care Medicine, Dec 1, 1994

Research paper thumbnail of P0366 / #1043: A Population-Based Study of Infants and Children Admitted to Intensive Care in Australia

Pediatric Critical Care Medicine, Mar 1, 2021

Research paper thumbnail of Peri-operative management of paediatric patients undergoing cardiac surgery – focus on respiratory aspects of care

Paediatric Respiratory Reviews, Dec 1, 2007

ABSTRACT Children requiring cardiac surgery present particular challenges in peri-operative respi... more ABSTRACT Children requiring cardiac surgery present particular challenges in peri-operative respiratory management. The wide variety of conditions and operations and their varied impact on respiratory function makes dialogue with related medical staff essential. In most circumstances, cardiac performance is the main determinant of respiratory outcomes. Changing cardiologic and surgical approaches have combined to diminish the severity and frequency of pulmonary hypertensive issues and new treatment modalities are simplifying the intensive care approach. Patients with Down&amp;#39;s syndrome and 22q11 deletion syndrome present particular issues related to anatomy, physiology and respiratory function. Certain conditions, including tetralogy of Fallot and cavopulmonary connections, present unique circumstances where respiratory management, sometimes including extubation, may assist in optimisation of cardiac performance. These and other conditions highlight the complexities of cardiopulmonary interactions. Cardiac performance remains the principal determinant of outcome after paediatric cardiac surgery and has the biggest impact on respiratory function.

Research paper thumbnail of Ontogeny of β-Adrenergic Receptors in Pulmonary Arterial Smooth Muscle, Bronchial Smooth Muscle, and Alveolar Lining Cells in the Rat

American Journal of Respiratory Cell and Molecular Biology, 1992

ABSTRACT beta-Adrenergic receptors play an integral role in the modulation of cell function in th... more ABSTRACT beta-Adrenergic receptors play an integral role in the modulation of cell function in the developing lung. In the rat, there are marked increases in beta receptor density in whole lung during postnatal maturation, but it is now known whether there are differential developmental changes in receptor density in specific cell types. Quantitative light microscopic autoradiography with [125I]iodocyanopindolol ([125I]ICYP) was used to determine maturational changes in beta-adrenergic receptor density in pulmonary arterial smooth muscle (ASM), bronchial smooth muscle (BSM), and alveolar lining cells (ALC) in rat lung during postnatal development (1 day to 6 mo). [125I]ICYP binding to whole lung sections revealed a single class of high-affinity receptors; agonist competitive binding studies suggested that the receptors are primarily of the beta 2 subtype. beta-Adrenergic receptor density in newborn (1 day) lung was lowest in ASM cells and was comparable in BSM cells and ALC. In contrast, in lungs from adult rats (3 mo), receptor density was similar in ASM versus BSM cells and was 2-fold greater in ALC. In addition, the maturational pattern of increasing receptor density differed in ASM compared with BSM and ALC. Receptor density in ASM increased 93% from 1 to 13 days, another 92% from 13 to 20 days, and was unchanged thereafter. In contrast, receptor density in BSM cells did not change from 1 to 13 days, but it increased 65% from 13 to 20 days, rose another 47% from 20 days to 3 mo, and increased an additional 24% from 3 to 6 mo.(ABSTRACT TRUNCATED AT 250 WORDS)

Research paper thumbnail of Humidified high‐flow nasal cannula oxygen in bronchiolitis reduces need for invasive ventilation but not intensive care admission

Journal of Paediatrics and Child Health, 2017

AimTo describe the changes to paediatric intensive care unit (PICU) admission patterns and ventil... more AimTo describe the changes to paediatric intensive care unit (PICU) admission patterns and ventilation requirements for children with bronchiolitis following the introduction of humidified high‐flow nasal cannula oxygen outside the PICU.MethodsRetrospective study comparing patients <24 months of age with a discharge diagnosis of bronchiolitis admitted to the PICU. A comparison was made between those before humidified high‐flow nasal cannula oxygen use (year 2008) to those immediately following the introduction of humidified high‐flow nasal cannula oxygen use (year 2011) and those following further consolidation of humidified high‐flow nasal cannula oxygen use outside the PICU (year 2013).ResultsHumidified high‐flow nasal cannula oxygen use up to 1 L/kg/min in the hospital did not reduce PICU admission. Intubation rates were reduced from 22.2% in 2008 to 7.8% in 2013. There was a non‐significant trend towards decreased length of stay in the PICU while hospital length of stay showe...

Research paper thumbnail of Association Between Centralization and Outcome for Children Admitted to Intensive Care in Australia and New Zealand: A Population-Based Cohort Study*

Pediatric Critical Care Medicine

Objectives: To describe regional differences and change over time in the degree of centralization... more Objectives: To describe regional differences and change over time in the degree of centralization of pediatric intensive care in Australia and New Zealand (ANZ) and to compare the characteristics and ICU mortality of children admitted to specialist PICUs and general ICUs (GICUs). Design: A retrospective cohort study using registry data for two epochs of ICU admissions, 2003–2005 and 2016–2018. Setting: Population-based study in ANZ. Patients: A total of 43,256 admissions of children aged younger than 16 years admitted to an ICU in ANZ were included. Infants aged younger than 28 days without cardiac conditions were excluded. Interventions: None. Measurements and Main Results: The primary outcome was risk-adjusted ICU mortality. Logistic regression was used to investigate the association of mortality with the exposure to ICU type, epoch, and their interaction. Compared with children admitted to GICUs, children admitted to PICUs were younger (median 25 vs 47 mo; p < 0.01) and stayed...

Research paper thumbnail of Factors associated with admission of children to an intensive care unit and readmission to hospital within 28 days of discharge: A population‐based study

Journal of Paediatrics and Child Health, 2021

AimHospital readmissions within 28 days are an important performance measurement of quality and s... more AimHospital readmissions within 28 days are an important performance measurement of quality and safety of health care. The aims of this study were to examine the rates, trends and characteristics of paediatric intensive care unit admissions, and factors associated with readmissions to hospital within 28 days of discharge.MethodsThis retrospective, population‐based record linkage study included all children ≥28 days and <16 years old admitted to an intensive care unit (ICU) in a New South Wales (NSW) public hospital from 2004 to 2013. Data were sourced from the NSW Admitted Patients Data Collection and the NSW Registry of Births, Deaths and Marriages, Death Registration.ResultsWe identified 21 200 ICU admissions involving 17 130 children. Admissions increased by 24% over the study period with the greatest increase attributed to respiratory and musculoskeletal conditions. A higher proportion of children were <5 years, male, lived in major cities, were publicly insured and had ch...

Research paper thumbnail of Use of forensic interview techniques to identify important handover information in post operative cardiac surgey procedures

Research paper thumbnail of A Comparison of expert and competent paediatric diagnosis

Research paper thumbnail of Inferior vena cavathrombosis asacomplication of femoral veincatheterisation

Indwelling femoral venous catheters were prospectively studied by ultrasonography to define the f... more Indwelling femoral venous catheters were prospectively studied by ultrasonography to define the frequency and evolution of inferior vena cava (IVC) thrombosis. IVC thrombosis was identified in six of 56 catheters (54 children). Only one patient with a positive ultrasound scan had clinical signs of thrombosis. All children with IVC thrombosis had had catheters in place for over six days. It is recommended that either the femoral central venous catheters are routinely changed at six days or ultrasound studies are routinely performed twice a week in all patients with catheters in situ for six or more days and that the catheter is removed immediately if evidence of thrombosis appears.

Research paper thumbnail of The Effect of Imputation of Pao 2/Fi o 2 From Spo 2/Fi o 2 on the Performance of the Pediatric Index of Mortality 3*

Pediatric Critical Care Medicine

Research paper thumbnail of Effect of post-mortem delay on density of tachykinin receptors in rat peripheral tissues

Peptides, 1998

The effect of post-mortem delay on the affinity and density of tachykinin NK 1 and NK 2 receptors... more The effect of post-mortem delay on the affinity and density of tachykinin NK 1 and NK 2 receptors was examined in the rat submandibular gland and gastric fundus, respectively, using saturation binding studies with the radioligands [ 125 I]Bolton-Hunter [Sar 9 , Met(O 2) 11 ]SP and [ 125 I][Lys 5 , Tyr(I 2) 7 , MeLeu 9 , Nle 10 ]NKA(4-10). For NK 1 receptors, no significant changes were seen in either K d (control 375 Ϯ 35 pM, n ϭ 5; 32 h post-mortem 390 Ϯ 59 pM, n ϭ 5) or B max (control 96 Ϯ 16 fmol/mg protein, n ϭ 5; 32 h post-mortem 62 Ϯ 10 fmol/mg protein, n ϭ 5). For NK 2 receptors, no alterations were seen up to 16 h post-mortem. However, significant (p Ͻ 0.001) changes were seen at 32 h post-mortem (n ϭ 4), where values for K d were increased (3.0 Ϯ 0.2 nM) and those for B max were reduced (42 Ϯ 5.9 fmol/mg protein), relative to control (K d ϭ 1.3 Ϯ 0.2 nM; B max ϭ 208 Ϯ 30 fmol/mg protein, n ϭ 5). These changes are probably related to observed histological deterioration. This study demonstrates the stability of tachykinin receptors in these peripheral tissues and indicates the suitability of post-mortem tissue as a valid control in future tachykinin receptor studies.

Research paper thumbnail of Primary immunization status of children attending the Port Moresby General Hospital

Papua and New Guinea medical journal, 1987

Research paper thumbnail of Effect of post-mortem delay on density of tachykinin receptors in rat peripheral tissues

Peptides, 1998

The effect of post-mortem delay on the affinity and density of tachykinin NK 1 and NK 2 receptors... more The effect of post-mortem delay on the affinity and density of tachykinin NK 1 and NK 2 receptors was examined in the rat submandibular gland and gastric fundus, respectively, using saturation binding studies with the radioligands [ 125 I]Bolton-Hunter [Sar 9 , Met(O 2) 11 ]SP and [ 125 I][Lys 5 , Tyr(I 2) 7 , MeLeu 9 , Nle 10 ]NKA(4-10). For NK 1 receptors, no significant changes were seen in either K d (control 375 Ϯ 35 pM, n ϭ 5; 32 h post-mortem 390 Ϯ 59 pM, n ϭ 5) or B max (control 96 Ϯ 16 fmol/mg protein, n ϭ 5; 32 h post-mortem 62 Ϯ 10 fmol/mg protein, n ϭ 5). For NK 2 receptors, no alterations were seen up to 16 h post-mortem. However, significant (p Ͻ 0.001) changes were seen at 32 h post-mortem (n ϭ 4), where values for K d were increased (3.0 Ϯ 0.2 nM) and those for B max were reduced (42 Ϯ 5.9 fmol/mg protein), relative to control (K d ϭ 1.3 Ϯ 0.2 nM; B max ϭ 208 Ϯ 30 fmol/mg protein, n ϭ 5). These changes are probably related to observed histological deterioration. This study demonstrates the stability of tachykinin receptors in these peripheral tissues and indicates the suitability of post-mortem tissue as a valid control in future tachykinin receptor studies.

Research paper thumbnail of Binding characteristics of endothelin ETA receptors in normal and post-mortem rat lung

Peptides, 2000

In control lung homogenates, optimal specific binding of [ 125 I]endothelin-1 and minimal filter ... more In control lung homogenates, optimal specific binding of [ 125 I]endothelin-1 and minimal filter binding was achieved using 50 g/ml bacitracin, 30 M phenylmethylsulphonyl fluoride (PMSF) and 10 mM EDTA. In post-mortem tissue (8, 16, and 32 h), no significant changes were seen in ET A receptor affinity (K d) or number (B max): control and 32 h K d ϭ 309 Ϯ 75, 225 Ϯ 32 pM and B max ϭ 173 Ϯ 42, 185 Ϯ 17 fmol/mg protein, respectively. Autoradiographic binding sites for [ 125 I]endothelin-1 were densely expressed on bronchiolar smooth muscle and parenchyma with moderate binding on epithelium and blood vessels. Histologic sections of post-mortem lung showed minimal deterioration of structures expressing ET A binding sites. Hence the ET A receptor is stable in the rat lung for up to 32 h post-mortem.

Research paper thumbnail of Ventilator-associated pneumonia in a tertiary paediatric intensive care unit: a 1-year prospective observational study

Critical care and resuscitation : journal of the Australasian Academy of Critical Care Medicine, 2012

To determine the incidence, risk factors and impact of ventilator-associated pneumonia (VAP) in a... more To determine the incidence, risk factors and impact of ventilator-associated pneumonia (VAP) in a mixed tertiary paediatric intensive care unit. Prospective observational study. Patients in the intensive care unit who were mechanically ventilated for more than 48 hours were assessed daily, according to criteria for a diagnosis of VAP. Potential risk factors for VAP, if present, were documented. Of 692 invasively ventilated patients, 269 (38.9%) were ventilated for > 48 hours and met no exclusion criteria. Eighteen (6.7%) patients had episodes of VAP, and the VAP incidence density was 7.02 per 1000 intubation days. The mean admission Paediatric Index of Mortality 2 risk of death was similar in patients with and without VAP (0.084 v 0.056; P =0.8). Patients with VAP (compared with patients without VAP) had a longer median duration of ICU stay, (19.35 v 7.35 days; P < 0.001), duration of ventilation (11.99 v 4.92 days; P=0.024) and duration of hospital stay (35.5 v 20 days; P &lt...

Research paper thumbnail of Use of propofol infusion in Australian and New Zealand paediatric intensive care units

Anaesthesia and intensive care

Despite the risk of propofol infusion syndrome, a rare but often fatal complication of propofol i... more Despite the risk of propofol infusion syndrome, a rare but often fatal complication of propofol infusion in ventilated children and possibly adults, propofol infusion remains in use in paediatric intensive care units (PICU). This questionnaire study surveys the current pattern of use of this sedative infusion in Australian and New Zealand PICUs. Thirty-three of the 45 paediatric intensive care physicians surveyed (73%), from 12 of the 13 intensive care units, returned completed questionnaires. The majority of practitioners (82%) use propofol infusion in children in PICU, the main indication being for short-term sedation in children requiring procedures. 39% of respondents consider propofol infusion useful in ventilated children requiring longer-term sedation. 67% of paediatric intensivists use maximum infusion doses that may be considered dangerously high (> or = 10 mg/kg/h). Nineteen per cent use propofol infusion for prolonged periods (> 72 hours). A smaller proportion (15%)...

Research paper thumbnail of Development and implementation of a feeding algorithm to optimise nutrition in Paediatric Intensive Care

Australian Critical Care, 2015

Research paper thumbnail of Congenital rubella--still with us

The Medical journal of Australia, Jan 23, 1986

Research paper thumbnail of Clonidine overdose in childhood: Implications of increased prescribing

Journal of Paediatrics and Child Health, 1998

To highlight the increase in the number of cases of clonidine overdose admitted to a specialist p... more To highlight the increase in the number of cases of clonidine overdose admitted to a specialist paediatric hospital, with particular reference to the clinical features, clinical course and circumstances surrounding the incident. Cases of clonidine overdose were identified by review of the emergency department attendance register, the intensive care unit database and inpatient statistics collection. Case notes were reviewed to determine the clinical features, history and clinical course in each case. Fifteen patients experienced 16 overdoses during the period 1990-97 inclusive. Only one case occurred before 1994. Depressed level of consciousness and bradycardia were the most common clinical manifestations, and were observed in 75 and 88% of cases respectively. There were no fatalities. Five patients received naloxone. Other treatment modalities included gastrointestinal decontamination, atropine, ventilation and inotropic support. Fourteen cases occurred in association with medication prescribed for attention-deficit hyperactivity disorder (ADHD). Clonidine overdose is a potentially serious condition, often requiring intensive care management. Our experience suggests that it is a growing problem, related in part to its increased use in the treatment of ADHD. Preventive strategies, including raising the level of awareness of risks, changes to packaging and appropriate selection of patients for treatment, need consideration if further overdoses are to be prevented.