Search PubMed⌕ Search

Biomedical subjects

Robert C Tasker

Publications and source records attributed to Robert C Tasker.

8 recordsLinked to original sources
PubMed2004

The neuroendocrine stress response and severity of acute respiratory syncytial virus bronchiolitis in infancy.

OBJECTIVE: Neuroendocrine hormones have profound effects on the immune system. The immune response is a major factor in the pathogenesis of acute respiratory syncytial virus (RSV) infection. We hypothesised that there is a relationship between the neuroendocrine response in acute RSV infection, the severity of illness, and the degree of lymphopenia. DESIGN: Prospective, non-randomised cohort study of infants hospitalised for RSV infection requiring mechanical ventilation or managed conservatively. The study assessed the effect of age, gender, birth gestation, and severity of illness on stress hormone profile and its relationship to lymphocyte count. SETTING: Regional Paediatric Intensive Care Unit (PICU) and children's wards. PATIENTS: Thirty-two consecutive infants with RSV infection were enrolled, of which thirteen were mechanically ventilated on PICU (study subjects) and nineteen treated on the ward (comparison group). Twenty-three children (72%) returned for follow-up. MEASUREMENTS AND MAIN RESULTS: A specific neuroendocrine profile was found in PICU patients compared to ward patients (Wilks Lambda = 0.36, F = 9.05, P =.03). PICU patients had significantly higher prolactin and growth hormone, and significantly lower leptin and IGF-1. Cortisol levels were the same. PICU patients were more lymphopenic compared to ward patients (P =.0001). On multiple regression analysis, prolactin and leptin levels accounted for 57% of the variation in lymphocyte count. CONCLUSIONS: Whereas the effect of intensive care (mechanical ventilation and medication) could not be controlled for, our results suggest that there is an association between the neuroendocrine hormone response, severity of illness and degree of lymphopenia.

Acute Disease↗
PubMed2003

Respiratory viruses in the intensive care unit.

Respiratory viruses cause a number of clinical 'syndromes' in the intensive care unit with different viruses being able to produce similar clinical pictures. Our main presenting problems are upper airway (e.g. croup and tracheitis), lower airway with intrapulmonary shunt (e.g. bronchitis and pneumonia), lower airway with dynamic hyperinflation (e.g. bronchiolitis and wheeze) and control of breathing (e.g. apnoea). This pragmatic classification is used because it enables focus on the physiological abnormality needing treatment, and how best to deliver appropriate and adequate ventilator support. This review provides an overview of these syndromes and a more detailed account of respiratory syncytial virus, our most commonly diagnosed winter illness.

Child, Preschool↗
PubMed2002

Interactive effects of high-frequency oscillatory ventilation and inhaled nitric oxide in acute hypoxemic respiratory failure in pediatrics.

OBJECTIVE: High-frequency oscillatory ventilation (HFOV) and inhaled nitric oxide (iNO) have been reported to improve oxygenation in children with acute hypoxemic respiratory failure (AHRF), but their roles in the treatment of AHRF remains unknown. The use of HFOV improves oxygenation by increasing lung recruitment. iNO can improve oxygenation in AHRF, but it may have limited efficacy in patients with poor lung inflation. Based on these findings, we hypothesized that the combined treatment of HFOV and inhalation of low-dose NO would improve oxygenation and survival in children with severe AHRF compared with children treated with conventional mechanical ventilation (CMV) or either treatment alone. SETTING: Tertiary pediatric intensive care units at seven academic centers. DESIGN: Post hoc analysis of data from children enrolled in a multicenter, randomized, masked study of the use of iNO in the treatment of AHRF. PATIENTS: A total of 108 pediatric patients with AHRF defined as an oxygenation index of >15 twice within 6 hrs. Mode of ventilation (HFOV or CMV) was determined by the patient's physician based on guidelines to maximize oxygenation. The patient was then randomized to treatment with or without iNO. Comparisons were made between patients who were treated with HFOV plus iNO (n = 14), HFOV alone (n = 12), CMV plus iNO (n = 35), and CMV alone (n = 38). INTERVENTIONS: Ventilation with CMV or HFOV with or without iNO. MEASUREMENTS AND MAIN RESULTS: We found that the change in Pao /Fio ratio was greatest in the HFOV plus iNO group compared with the other treatment groups at 4 hrs (p =.02) and 12 hrs (p =.01). After 24 hrs of treatment, both HFOV plus iNO and HFOV alone resulted in greater improvement in Pao2/Fio2 ratio than either CMV alone or CMV plus iNO (p =.005). After 72 hrs, treatment with HFOV alone resulted in a greater improvement in Pao2/Fio2 ratio than either CMV alone or CMV plus iNO (p =.03). There was no difference in predefined treatment failures between treatment groups. CONCLUSIONS: We conclude that the combination of HFOV with iNO causes a greater improvement in oxygenation than either treatment strategy alone in children with severe AHRF. We speculate that the enhanced lung recruitment by HFOV enhances the effects of low dose iNO on gas exchange.

Administration, Inhalation↗