Search PubMed⌕ Search

Biomedical subjects

F Shann

Publications and source records attributed to F Shann.

At least 19 recordsLinked to original sources
PubMed2002

Systematic review of rheumatic heart disease prevalence in children in developing countries: the role of environmental factors.

OBJECTIVES: To consider the worldwide prevalence of rheumatic heart disease in children in developing countries using surveys with uniform methodologies, and to consider the effect of environmental factors including socio-economic status, overcrowding, urbanization, nutrition and access to medical services on the distribution of rheumatic heart disease in developing countries. METHODS: Sixty-one surveys of the prevalence of rheumatic heart disease in developing countries were found using a systematic review of MEDLINE from January 1976 to July 1999. Twenty-four studies were selected for comparison based on their uniform methodological and diagnostic techniques. RESULTS: There is a high prevalence of rheumatic heart disease in the Pacific region with a lower prevalence in the Indian subcontinent, Asian, sub-Saharan African, Mediterranean, Latin American and Caribbean regions. However, aside from the Indian subcontinent, these regions have not been well studied, and it may be that the true prevalence is actually higher. CONCLUSIONS: There is a lack of good quality prevalence surveys of rheumatic heart disease in developing countries. It appears that a threshold level where higher socio-economic status is associated with reduced prevalence of rheumatic heart disease is not reached in developing countries. Therefore, differences in prevalence between socio-economic groups in the one area cannot be detected. A similar case can be made for overcrowding. Many regions need well-designed studies of rheumatic heart disease that incorporate assessment of environmental factors as well as the study of the microbiological epidemiology of rheumatic heart disease and group A streptococci.

Acute Disease↗
PubMed2001

A randomized trial of very early decompressive craniectomy in children with traumatic brain injury and sustained intracranial hypertension.

OBJECT: The object of our study was to determine, in children with traumatic brain injury and sustained intracranial hypertension, whether very early decompressive craniectomy improves control of intracranial hypertension and longterm function and quality of life. METHODS: All children were managed from admission onward according to a standardized protocol for head injury management. Children with raised intracranial pressure (ICP) were randomized to standardized management alone or standardized management plus cerebral decompression. A decompressive bitemporal craniectomy was performed at a median of 19.2 h (range 7.3-29.3 h) from the time of injury. ICP was recorded hourly via an intraventricular catheter. Compared with the ICP before randomization, the mean ICP was 3.69 mmHg lower in the 48 h after randomization in the control group, and 8.98 mmHg lower in the 48 hours after craniectomy in the decompression group (P=0.057). Outcome was assessed 6 months after injury using a modification of the Glasgow Outcome Score (GOS) and the Health State Utility Index (Mark 1). Two (14%) of the 14 children in the control group were normal or had a mild disability after 6 months, compared with 7 (54%) of the 13 children in the decompression group. Our conclusion was that when children with traumatic brain injury and sustained intracranial hypertension are treated with a combination of very early decompressive craniectomy and conventional medical management, it is more likely that ICP will be reduced, fewer episodes of intracranial hypertension will occur, and functional outcome and quality of life may be better than in children treated with medical management alone (P=0.046; owing to multiple significance testing P <0.0221 is required for statistical significance). This pilot study suggests that very early decompressive craniectomy may be indicated in the treatment of traumatic brain injury.

Brain Injuries↗
PubMed2001

Nasopharyngeal oxygen therapy produces positive end-expiratory pressure in infants.

UNLABELLED: The World Health Organisation recommends nasopharyngeal catheters as a safe and efficient method of oxygen administration in infants. However, little is known about the mechanisms of the improvement in oxygenation. The aim of the present study was to determine whether nasopharyngeal oxygen therapy produces positive end-expiratory pressure (PEEP). Nine spontaneously breathing infants (median age 13 months, range 10 days to 20 months) after heart surgery were investigated. All patients had normal pulmonary blood flow at the time of the study (Qp:Qs=1:1). Oxygen (oxygen fraction 1.0) was delivered by an 8 F catheter inserted into the nasopharynx (tip just visible below the soft palate). The pulmonary mechanics were analysed using a single compartment model of the respiratory system. Oesophageal pressure (Pes) at end-expiration, dynamic lung compliance (C(L)) and resistance (R(L)), minute ventilation, PaCO2 and PaO2 were measured at baseline without a nasopharyngeal catheter or oxygen, and at oxygen flows of 0.5 l/min, 1.0 l/min and 2.0 l/min. All the flows generated significant increases in PEEP. Mean difference in PEEP (SD, paired t-test versus baseline): 1.6 cm H2O (1.4, P=0.008) with 0.5 l/min of oxygen; 2.8 cm H2O (2.7, P=0.014) with 1.0 l/min of oxygen; and 4.0 cm H2O (2.9, P = 0.004) with 2.0 l/min of oxygen. There was a significant correlation between all the nasopharyngeal flows (in ml/kg per min) and the generated PEEP (P<0.001) and between the C(L) values and the generated PEEP (P < 0.05). There was no significant difference in PaCO2 and R(L). Minute ventilation was significantly less with nasopharyngeal oxygen than at baseline. As expected, PaO2 increased significantly with increasing oxygen flows. CONCLUSION: Administration of oxygen through an 8 F nasopharyngeal catheter at flow rates recommended by the World Health Organisation (0.5 l/min in newborns, 1.0 l/min in infants) produces moderate amounts of positive end-expiratory pressure. The levels achieved may contribute to an improvement in oxygenation by altering the visco-elastic properties of the lung.

Female↗
PubMed2001

Calibration of the paediatric index of mortality in UK paediatric intensive care units.

AIM: To test a paediatric intensive care mortality prediction model for UK use. METHOD: Prospective collection of data from consecutive admissions to five UK paediatric intensive care units (PICUs), representing a broad cross section of paediatric intensive care activity. A total of 7253 admissions were analysed using tests of the discrimination and calibration of the logistic regression equation. RESULTS: The model discriminated and calibrated well. The area under the ROC plot was 0.84 (95% CI 0.819 to 0.853). The standardised mortality ratio was 0.87 (95% CI 0.81 to 0.94). There was remarkable concordance in the performance of the paediatric index of mortality (PIM) within each PICU, and in the performance of the PICUs as assessed by PIM. Variation in the proportion of admissions that were ventilated or transported from another hospital did not affect the results. CONCLUSION: We recommend that UK PICUs use PIM for their routine audit needs. PIM is not affected by the standard of therapy after admission to PICU, the information needed to calculate PIM is easy to collect, and the model is free.

Calibration↗
PubMed2000

The immature-to-total neutrophil ratio (IT ratio) is a sensitive indicator of sepsis after paediatric cardiopulmonary bypass.

Cardiopulmonary bypass (CPB) causes a systemic inflammatory response syndrome (SIRS) with activation of neutrophils (increased immature-to-total neutrophil ratio, IT ratio). Does an additional inflammatory response induced by sepsis further increase the IT ratio, so that it can still be used as an indicator of sepsis? In 160 children we analysed retrospectively the IT ratios from the day before CPB to the 10th day after the operation (controls). The 95% confidence limits of the controls were plotted against postoperative day and compared with the IT ratio courses in all children of a 4-year period who developed sepsis during the first 10 days after CPB. All septic children (n = 9) had IT ratios above the upper 95% confidence limits of the controls on the day of positive culture or on the following day. The IT ratio remains a sensitive indicator of sepsis even after CPB.

Cardiopulmonary Bypass↗
PubMed2000

Antibiotics for preventing pneumonia in children with measles.

BACKGROUND: Measles causes more than a million deaths a year, of which most are children under five years of age who die from pneumonia. OBJECTIVES: The objective of this review was to assess the effects of antibiotics given to children with measles on reducing pneumonia or mortality, and to assess whether antibiotics should be given to all children with measles in communities with a high fatality rate. SEARCH STRATEGY: We searched MEDLINE (1966 - 1999), EMBASE (1980-1999) and the specialized trials register of the Acute Respiratory Infections Group in August 1999, and all relevant journals in the University of Melbourne medical library for the years 1935-46. SELECTION CRITERIA: Randomised or controlled trials of antibiotics for children with measles. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed trial quality. MAIN RESULTS: Six trials with 1304 children were included. All but one of the trials were unblinded, and randomisation was either not described or was by alternate allocation. In four studies, the incidence of pneumonia in the control group was similar to that in the antibiotic prophylaxis group; in the other two studies, the incidence of pneumonia was unusually high in the control group so these children had a higher complication rate than the antibiotic group. Four of the 764 children given antibiotics died compared with one of the 637 controls. REVIEWER'S CONCLUSIONS: The quality of the trials reviewed was poor, and they provide very weak evidence for giving antibiotics to all children with measles. Available evidence suggests that antibiotics should be given only if a child has clinical signs of pneumonia or other evidence of sepsis.

Anti-Bacterial Agents↗