Randomized Study of High-Frequency Oscillatory Ventilation in Infants With Severe Respiratory Distress Syndrome Durand DJ; for the HiFO Study Group (Children's Hosp, Oakland, Calif) J Pediatr, 122:609-619, 1993 104-94-8-2 Purpose.--Although high-frequency ventilation is an effective means of oxygenation and ventilation, it is not known whether it offers any advantage to the infant with respiratory distress syndrome (RDS). For these patients, high-frequency oscillatory ventilation (HFOV) offers the potential for adequate oxygenation and ventilation with extremely small tidal volumes. A multicenter, prospective, randomized study determined whether HFOV could prevent or slow the development of air leak syndrome (ALS) in infants with severe RDS. Methods.--Eighty-six infants were assigned to receive HFOV and 90 to receive conventional ventilation. All patients were younger than 48 hours of age, weighed at least .5 kg at birth, and had severe RDS, as defined by peak inspiratory pressure or the presence of ALS. The ventilator providing HFOV operated at 15 Hz, using an inspiratory-expiratory ratio of 1:2 with no background tidal breaths. The study definition of ALS was pulmonary interstitial emphysema, scored in blinded fashion, or some type of gross air leak, scored by duration and number of chest tubes required. Results.--In the first 24 hours, the HFOV group received a significantly higher mean airway pressure with lower inspired oxygen concentration, a lower arterial carbon dioxide tension, and a higher ratio of arterial-to-alveolar oxygen tension. After adjustment for birth weight, study site, and inborn vs. outborn status, the HFOV group had a significant reduction in the development of ALS among those who did not have it at baseline, 42% vs. 63%. The 2 groups did not differ in incidence of patent ductus arteriosus, 30-day survival, or need for ventilation at 30 days. Conclusion.--For infants with severe RDS, HFOV that uses a high mean airway pressure can provide effective ventilation as it improves oxygenation and reduces the development of ALS. It did not appear to decrease the progression of ALS in patients who had it at study entry. The main effect of HFOV appeared to be a decrease in the incidence of mild pulmonary interstitial edema.
Elective high-frequency oscillatory ventilation versus conventional ventilation in preterm infants with pulmonary dysfunction: systematic review and meta-analyses. Bhuta T - Pediatrics - 01-NOV-1997; 100(5): E6 From NIH/NLM MEDLINE NLM Citation ID: 9347000 (PubMed) Full Source Title: Pediatrics Publication Type: Journal Article; Meta-Analysis Language: English Author Affiliation: NSW Center for Perinatal Health Services Research at the University of Sydney and Department of Neonatal Medicine, Royal Prince Alfred Hospital, Sydney, NSW, Australia. Authors: Bhuta T; Henderson-Smart DJ Abstract: OBJECTIVES: To systematically review the evidence to determine whether the routine use of high-frequency oscillatory ventilation (HFOV) as compared with conventional ventilation (CV) is beneficial or harmful in preterm infants requiring mechanical ventilation for pulmonary failure principally due to respiratory distress syndrome. METHODS: All randomized controlled trials of elective HFOV versus CV in preterm infants <36 weeks' gestation with respiratory failure mainly attributable to respiratory distress syndrome were identified from the literature through a search of MEDLINE, EMBASE, Oxford database of Perinatal trials, and previous reviews including cross-references and abstracts. Meta-analyses using event rate ratios (ERR), event rate difference, and if significant, number needed-to-treat were calculated (95% confidence limits were used for all analyses). Two prespecified subgroup analyses were performed. RESULTS: Four published trials were included. Meta-analyses revealed the following ERR (95% confidence intervals) for HFOV versus CV: mortality at 28 to 30 days, 1.02 (0.76, 1.39); chronic lung disease (CLD) at 28 days, 0.86 (0.73, 1.01); mortality or CLD, 0.9 (0.80, 1. 01); air-leak syndromes, 1.13 (0.97, 1.33); mechanical ventilation at 28 days, 1.06 (0.84, 1.33); supplemental oxygen at discharge, 0. 59 (0.37, 0.92); intraventricular hemorrhage (IVH) all grades, 1.11 (0.95, 1.29); IVH (grades 3 or 4), 1.32 (1.01, 1.72); and periventricular leukomalacia, 1.39 (0.91, 2.13). In the subgroup of trials in which a high volume strategy (HVS) was used the ERR for CLD was 0.53 (0.36, 0.78); mortality or CLD, 0.56 (0.40, 0.77); supplemental oxygen at discharge, 0.57 (0.36, 0.92); IVH (all grades), 0.90 (0.61, 1.33); and IVH (grades 3 or 4), 0.84 (0.39, 1. 84). Results were similar to these for the trials using surfactant. One recent trial suggests that HFOV may reduce the cost of in-hospital care. CONCLUSIONS: The overall meta-analysis is dominated by the HIFI study, which was criticized for its methodology and surfactant was not used. Subsequent studies, most of which used HVS and/or surfactant, have shown benefits in measures of CLD without an increase in rates of IVH. Caution is warranted in interpreting these results because: 1) the treatment is not blinded and this could affect some outcomes; 2) except for one small trial postneonatal survival, lung function, and neurodevelopment have not been reported from HVS trials; and 3) the benefits and disadvantages have not been reported in infants born at different gestational ages or different birth weights. Importantly, results from groups experienced in the use of HFOV may not be readily generalizable.
RR 30 for infants up to 1 year of age; 20 for those 1-6 years of age and 15 for those greater than 6
(normal respiratory rates for age).
I Time Based upon an I:E ratio of 1:2 for infants and pre-school age children and 1:2.5 for schoolage and adolescents. Therefore, 0.7 sec for infants up to 1 year of age ; 1 sec for those to 6 years of age and 1.2 secs for those greater than 6.
Tidal Volume 10 cc/kg (Range 8-12 cc/kg).
Guideline ในการตั้งเครื่องช่วยหายใจเบื้องต้น (12) 1. เลือก mode ของเครื่องช่วยหายใจที่คุ้นเคยมากที่สุด โดยจุดประสงค์ของการช่วยหายใจคือให้การช่วยหายใจเพื่อทำให้มีการแลกเปลี่ยนกาซที่เพียงพอ (adequate oxygenation/ventilation) ลดงานซึ่งเกิดจากการหายใจ (reduced work of breathing) หายใจมีปฏิสัมพันธ์กับเครื่องช่วยหายใจ (synchrony between patient and ventilator) (12,17) หลีกเลี่ยงการใช้ความดันขนาดสูง (avoidance of high end-inspiration pressures) 2. ควรตั้งปริมาณความเข้มข้นออกซิเจนขนาดสูงก่อน อาจตั้งโดยใช้ออกซิเจน FiO 2 1.0 ก่อนแล้วค่อยๆลดขนาดลงเพื่อพยายามคงค่าความอิ่มตัวออกซิเจนในเลือด (oxygen saturation,SaO 2 ) ให้ได้ประมาณ 92-95% ในรายที่มีความผิดปกติของปอดรุนแรง เช่นภาวะ Adult Respiratory Distress Syndrome (ARDS) อาจยอมรับที่ค่าค่าความอิ่มตัวออกซิเจนในเลือดมากกว่าหรือเท่ากับ 88% (12,18)
Bhuta et al Elective high-frequency oscillatory ventilation versus conventional ventilation in preterm infants twith pulmonary dysfunction: systematic review and meta-analysis Pediatrics 1997 100 e6,7p