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John Massie

Publications and source records attributed to John Massie.

17 recordsLinked to original sources
PubMed2006

Polyflex stenting of tracheomalacia after surgery for congenital tracheal stenosis.

Polyflex self-expanding stents (Rüsch, Germany) were used in three young children who had presented with life-threatening long-segment tracheal stenosis with bronchial stenosis in two cases. Two children had slide tracheoplasties and subsequently aortic homografts and another tracheal resection and autotracheoplasty. However, in all cases persistent lower tracheal malacia necessitated stenting. Complications of granuloma, stent migration or dislodgement occurred in all cases. A fatal tracheo-aortic fistula occurred in one child. Granuloma in one was treated successfully with steroids. One child survives.

Aorta, Thoracic↗
PubMed2006

Cough in children: when does it matter?

Cough is a common presenting symptom to paediatricians and paediatric respiratory physicians. The causes of chronic cough in childhood are significantly different from those in adults, and a different approach to diagnosis and management is needed. In most cases cause can be identified or a satisfactory label given. This review will cover the approach to cough in children and cover some specific causes of troublesome cough not discussed elsewhere in this mini-symposium.

Adolescent↗
PubMed2006

Parental attitudes to the identification of their infants as carriers of cystic fibrosis by newborn screening.

AIM: To investigate parental attitudes to cystic fibrosis (CF) carrier detection of their infant by newborn screening (NBS). METHODS: Data were collected from a postal questionnaire sent to parents of infants identified as CF carriers by NBS in 1996-1997 (inclusive) and 2001 in Victoria, Australia (n = 66). RESULTS: Almost all parents remembered their child being identified as a CF carrier (97%: 1996/1997; 100%: 2001); yet the majority were unaware at the time that NBS could detect carriers (70%: 1996/1997; 49%: 2001). More parents in the later cohort reported having carrier testing compared with the earlier cohort (85% and 53% respectively) but recall was more uncertain in the earlier cohort when validated against health records. Cascade testing was not utilised frequently by other family members in either cohort. Residual risk of being a carrier if testing was negative was not well understood by parents. Some parents (28%: 1996/1997; 18%: 2001) had residual anxiety about the current health of their carrier child and their future reproductive decision making. Most parents were satisfied with the information provided to them at the time of the sweat test. Few differences were seen between the cohorts. CONCLUSION: Although the NBS process for CF in Victoria is working efficiently for the majority of families whose infant is identified as a carrier there are areas that can be improved. We recommend that greater attention should be given to informing parents that a consequence of NBS is CF carrier detection and strategies to improve utilisation of cascade testing should be developed.

Adult↗
PubMed2006

Pharmacokinetic profile of once daily intravenous tobramycin in children with cystic fibrosis.

AIM: Once-daily tobramycin in patients with cystic fibrosis (CF) is a more convenient dosing regimen than thrice daily dosing. There are limited data on the pharmacokinetic (PK) profile for once-daily tobramycin in patients with CF. The aim of this study was to define the PK parameters for once-daily tobramycin in children with CF and develop an algorithm for therapeutic drug monitoring dosing. METHODS: CF patients admitted to hospital were commenced on once-daily intravenous tobramycin (12 mg/kg/day) and ticarcillin/clavulinic acid. Serum tobramycin levels were taken at 30 min, 2-4 h and 12 h post dose. Data points for the PK model included: age, sex, weight, tobramycin dose, time of tobramycin doses and levels, tobramycin levels. WinNonMix was used to obtain the PK parameters. RESULTS: Forty-four children with 86 admissions who were aged 9 months-20 years were included. A one-compartment intravenous infusion model with first order elimination kinetics produced the best model. Population parameters were: volume of distribution (V(d)) = 0.267 L/kg (95% confidence interval (CL) 0.260-0.272), clearance (CL) 0.103 L/kg/h (95% CI 0.098-0.107) and half-life (t(1/2)) 1.82 (95% CI 1.77-1.88) h. Once the population model was established post hoc analysis was used to calculate individual subject predictions. Plots of individual prediction curves agreed well with observed values. CONCLUSION: This study has established an algorithm for routine monitoring of once-daily tobramycin in children with CF. Satisfactory serum levels of tobramycin were obtained with a dose of 12 mg/kg/day and a regimen algorithm that uses only one measurement to monitor the plasma concentration is suggested.

Adolescent↗
PubMed2006

Changing their minds with time: a comparison of hypothetical and actual reproductive behaviors in parents of children with cystic fibrosis.

OBJECTIVE: Newborn screening for cystic fibrosis, with appropriate counseling, enables carrier parents to be informed early about future reproductive choices. Previous studies have assessed attitudes toward reproductive decisions in a hypothetical pregnancy or have measured reproductive behaviors. We aimed to measure parent attitudes to reproductive technologies and to compare prospectively these attitudes with later reproductive behaviors. METHODS: Parents of children who had cystic fibrosis and were aged 2 to 7 years were surveyed at baseline using a written questionnaire that explored attitudes to prenatal testing and termination of pregnancy in a hypothetical pregnancy. Parent knowledge and access to genetic counseling services also were assessed. Five years later, we compared attitudes with actual reproductive behaviors. RESULTS: Fifty-six mothers participated at baseline, and 43 were resurveyed 5 years later. Parent knowledge of cystic fibrosis and genetics was very good. A total of 93% had met a genetic counselor at the time of diagnosis, and more than half had on at least 1 subsequent occasion. At baseline, 82% reported that they would be likely to have prenatal diagnosis in a subsequent pregnancy, and 56% reported that they would be likely to terminate an affected pregnancy. Twenty-seven mothers since had been pregnant, with prenatal diagnosis used in 33 of the 55 pregnancies. In 67%, the hypothetically reported behavior regarding use of prenatal testing was the same as their actual behavior. Five of the 33 tested pregnancies were affected; all ended in termination. Reproductive choices in relationship to the number of children wanted, together with attitudes toward prenatal diagnosis and termination of pregnancy, were dynamic over time, with decisions having changed in both directions. CONCLUSIONS: This cohort of parents has actively used reproductive technologies since the birth of a child who has cystic fibrosis that was diagnosed by newborn screening. The dynamic aspect of reproductive choices highlights the importance of ongoing access to genetic counseling beyond the initial period of diagnosis and education, regardless of whether parents report that they expect to use reproductive technologies.

Abortion, Induced↗
PubMed2005

The CT appearances of delayed amniotic fluid clearance from the lungs in an infant with absent pulmonary valve and congenital lobar emphysema.

Congenital lobar emphysema (CLE) is a cause of severe neonatal respiratory distress. Overexpansion of the affected pulmonary lobe in the fetus is due to narrowing of the airway, with a resultant 'ball-valve' effect. At birth, there may be delayed clearance of fetal lung fluid. Early chest radiographs show opacification of the hyperexpanded lobe. The CT findings in the immediate neonatal period have not been previously reported. We describe the imaging in a neonate with tetralogy of Fallot and absent pulmonary valve with secondary CLE. CT demonstrates the hyperexpanded lobe with initial thickening of the interlobular septa and alveolar ground glass attenuation, with subsequent clearing. This resorption of fetal lung fluid via the pulmonary interstitium should not be confused with interstitial lung disease.

Amniotic Fluid↗
PubMed2005

Pulmonary capillary haemangiomatosis in a premature infant.

Pulmonary capillary haemangiomatosis (PCH) is a rare disorder characterized by widespread capillary proliferation in the lung, infiltrating the interstitium and the alveolar walls. We present the HRCT features of PCH in a surviving ex-premature infant. To our knowledge, this is a unique case of the radiological features of PCH in a young living infant.

Hemangioma, Capillary↗
PubMed2005

Effects of segregation on an epidemic Pseudomonas aeruginosa strain in a cystic fibrosis clinic.

The detection of a clonal Pseudomonas aeruginosa strain in 21% of children attending a cystic fibrosis clinic during 1999, which may have led to a worse prognosis, prompted strict infection control measures, including cohort segregation. We determined whether these strategies interrupted cross-infection within the clinic. Patients from 1999 were observed and a cross-sectional study of the 2002 clinic was performed. By 2002, the epidemic strain prevalence had decreased from 21 to 14% (p = 0.03), whereas the proportion of patients with nonepidemic P. aeruginosa strains was unchanged. The age- and sex-adjusted relative risk for epidemic strains among sputum producers in 2002 compared with 1999 was 0.64 (95% confidence interval, 0.47, 0.87; p = 0.004). Increased mortality or transfer to another clinic did not explain this reduction. Although children with epidemic strains may have had increased mortality (adjusted odds ratio, 2.0; 95% confidence interval, 0.6-6.8), they did not demonstrate greater morbidity than those with other P. aeruginosa isolates. Successful infection control measures provided additional indirect evidence for person-to-person transmission of an epidemic strain within the clinic. Further studies are needed to resolve whether cohort segregation completely eliminates cross-infection and if acquisition of epidemic isolates is associated with worse outcomes.

Adolescent↗
PubMed2005

Diagnosis of cystic fibrosis after newborn screening: the Australasian experience--twenty years and five million babies later: a consensus statement from the Australasian Paediatric Respiratory Group.

Newborn screening for cystic fibrosis has been used in Australia and New Zealand for over 20 years. In that time, considerable experience has been developed regarding the early diagnosis of cystic fibrosis after newborn screening. To date, there has not been a consensus on the process of screening and clinical evaluation leading to the diagnosis of cystic fibrosis in infants, many of whom are not symptomatic at time of notification of the screening result. The aim of this paper is to provide some consensus on the important issues of a cystic fibrosis diagnosis arising from newborn screening, based on the experience gained in Australia and New Zealand over the last 20 years.

Australasia↗
PubMed2005

The relevance of sweat testing for the diagnosis of cystic fibrosis in the genomic era.

Cystic fibrosis (CF) is the most common inherited disorder of childhood. The diagnosis of CF has traditionally been based on clinical features with confirmatory evidence by sweat electrolyte analysis. Since 1989 it has been possible to also use gene mutation analysis to aid the diagnosis. Cloning of the cystic fibrosis transmembrane conductance regulator (CFTR) gene has advanced our understanding of CF, in particular the molecular basis of an expanded CF phenotype. However, because there are over 1000 mutations and 200 polymorphisms, many without recognised effects on CFTR, the molecular diagnosis can be troublesome. This has necessitated measurement of CFTR function with renewed interest in the sweat test. This review provides an overview of the clinical features of CF, the diagnosis and complex genetics. We provide a detailed discussion of the structure and function of CFTR and the classification of CFTR mutations. Sweat electrolyte analysis is discussed, from the physiology of sweating to the rigours of a properly performed sweat test and its interpretation. With this information it is possible to understand the relevance of the sweat test in the genomic era.

Journal Article↗
PubMed2004

Internal mandibular distraction to relieve airway obstruction in infants and young children with micrognathia.

Micrognathia may cause upper airway obstruction requiring complex medical interventions and sometimes tracheostomy. The role of distraction techniques to lengthen the mandible is yet to be clarified. The aim of this paper is to present a series of five cases in which mandibular lengthening by osteotomy and internal distraction was used to relieve airway obstruction. Five patients whose ages ranged from 4-39 months (mean, 15 months) were managed at our center with internal distraction osteogenesis to relieve airway obstruction. Three patients had a tracheostomy, and two patients had refractory airway obstruction prior to distraction. Following osteotomy and insertion of internal distraction devices, the mandible was distracted a mean of 17 mm (range, 15-25 mm). The distraction devices were removed at the end of a consolidation period ranging from 3-10 weeks. Two of 3 patients with a tracheostomy were decannulated, while the third patient with tracheostomy is awaiting choanal atresia repair before being decannulated. The two patients who were not managed with a tracheostomy but who had persistent upper airway obstruction have not required further airway intervention after mandibular distraction. In conclusion, mandibular lengthening by distraction osteogenesis can relieve airway obstruction in infants and small children. This is a promising new technique that may avoid the need for tracheostomy in some infants with micrognathia, and facilitate early decannulation in those who have a tracheostomy.

Airway Obstruction↗
PubMed2004

National study of infants hospitalized with pertussis in the acellular vaccine era.

BACKGROUND: In Australia in 1999 acellular pertussis vaccine (DTPa) replaced locally manufactured whole cell vaccine given at 2, 4 and 6 months of age with coverage of about 95% by 12 months of age. Few data are available on pertussis hospitalizations or sources of infection in countries exclusively using DTPa. METHODS: In 2001 national active monthly surveillance of infant hospitalizations for pertussis was conducted through the Australian Pediatric Surveillance Unit, which surveys all child health specialists monthly. A standard questionnaire was completed for notified cases. RESULTS: There were 140 infants reported (median age at diagnosis, 8 weeks). The rate of hospitalization in indigenous infants was significantly higher than in nonindigenous infants (P < 0.01). Of 97 (69%) infants who had not been vaccinated for pertussis, 63 (65%) were <8 weeks old (before the first scheduled dose of DTPa vaccine). Of 76 infants age > or =8 weeks, only 28 (37%) were appropriately immunized for age. Of 68 coughing contacts whose ages were known, 46 (68%) were adults, usually one of the infant's parents. Of 32 child contacts 16 (50%) were siblings. Four infants <6 weeks old died. CONCLUSION: Despite universal vaccination with DTPa in Australia, pertussis remains an important cause of hospitalization, morbidity and death in infants, most of whom were too young to be vaccinated or had missed vaccinations. The most common source of infection was a parent. Strategies to improve pertussis control in countries with high DTPa coverage could include adult-formulated booster pertussis vaccines for adolescents and recent parents and/or accelerated pertussis vaccine schedules for infants.

Australia↗
PubMed2002

Exercise-induced asthma in children.

Exercise-induced asthma (EIA) is a relatively common problem in children, but may not be recognized because children either do not report their symptoms, or avoid activities that cause it. Clarifying the diagnosis of EIA, in particular separating EIA from other causes of exertional dyspnea, is essential. Treating EIA in children is challenging because of the nature of their physical activities, which are often not planned, and may be prolonged. Keeping children active is an important goal to ensure healthy physical and social development. Many children with EIA are well managed with an inhaled short-acting beta(2)-adrenoceptor agonist before exercise or if symptoms develop. The approach to more troublesome EIA depends on whether the child has persistent asthma and requires better prevention, or the EIA is an isolated clinical problem. The options for treatment also depend on the timing, frequency, and duration of activity that induces EIA. Options include the addition of a cromone, a leukotriene modifier, an inhaled corticosteroid, or switching to use a long-acting beta(2)-adrenoceptor agonist. The use of warm-up exercises has been shown to be helpful by using the refractory period but is not practical for most children with EIA. A final consideration for successful management of EIA in children is that the delivery of medication needs to be age-appropriate.

Administration, Inhalation↗
PubMedDate not supplied

Double aortic arch presenting as severe bronchiolitis in a 2-week-old infant.

A 2-week-old female infant was transferred from a regional hospital for mechanical ventilation after developing severe respiratory distress. Stridor had been present since the age of 1 week and was complicated by coryzal illness. Mechanical ventilation was difficult with marked inspiratory and expiratory flow obstruction recorded by the ventilator. Echocardiogram showed a normal heart. Flexible bronchoscopy revealed mid-tracheal extrinsic compression (unchanged with positive end-expiratory pressure) and advancement of the endotracheal tube by 2 cm completely corrected the flow obstruction. Repeat echocardiogram showed a double aortic arch. This case report emphasizes the importance of clinical history, examination findings and interpretation of the ventilator waveforms in the differential diagnosis of a difficult-to-ventilate infant with bronchiolitis.

Aorta, Thoracic↗