To study the effects of apneic pauses, sighs, and breathing patterns on functional residual capacity (FRC), we measured FRC repeatedly in 48 healthy preterm infants (weight at study 2,042 +/- 316 g [mean +/- SD], postconceptional age 36.6 +/- 2.0 wk), during unsedated sleep using a modified heliox/nitrogen washout technique. Breathing movements and pulse oximeter saturation (SpO2) were recorded throughout and recordings analyzed for the presence of regular and nonregular breathing pattern, apneic pauses, sighs, and desaturations (SpO2 < 90%) during the last 2 min prior to each FRC measurement. FRC was lower during nonregular than during regular breathing pattern (23.3 +/- 7.2 ml/kg versus 26.9 +/- 7.8 ml/kg, p < 0.02); however, this apparent effect of breathing pattern disappeared after controlling the data for apneic pauses. Apneic pauses resulted in a significant decrease in FRC: mean FRC was 20.0 +/- 6.8 ml/kg if measured within 2 min of an apneic pause, 26.0 +/- 6.9 ml/kg if measured after a sigh (p < 0.001), and 24.0 +/- 7.7 ml/kg if there had been neither a sigh nor an apneic pause (p < 0.05). The interval between the apneic pause and the FRC measurement had no effect on FRC. There was an inverse correlation between FRC and the speed with which SpO2 fell during desaturation (r = -O.5, p < 0.03). Apneic pauses resulted in a persistent reduction in FRC in these preterm infants. Sighs appeared to restore FRC. The significant relationship between FRC and the speed of desaturation found in this study underscores the importance of endogenous or exogenous strategies that help to increase FRC, such as sighs or the application of continuous positive airway pressure, for the stability of oxygenation in preterm infants who have difficulty maintaining their oxygenation.

Importance: There are potential benefits and harms of hyperoxemia and hypoxemia for extremely preterm infants receiving more or less supplemental oxygen. Objective: To compare the effects of different pulse oximeter oxygen saturation (SpO2) target ranges on death or major morbidity.Design, Setting, and Participants: Prospectively planned, individual participant data meta-analysis of five randomized clinical trials (conducted 2005-2014), enrolling infants born at less than 28 weeks' gestation.Exposure: Targeting a lower (85-89%) versus higher (91-95%) SpO2 range. Main Outcomes and Measures:The primary outcome was a composite of death or major disability by 18-24 months' corrected age (bilateral blindness, deafness, cerebral palsy with the Gross Motor Function Classification System (GMFCS) level 2 or higher, or Bayley-III cognitive or language score less than 85). There were 16 secondary outcomes including death, major disability, retinopathy of prematurity (ROP) requiring treatment, blindness, severe necrotizing enterocolitis (NEC).

Overnight 12 hour tape recordings of arterial oxygen saturation (SaO2, pulse oximeter in the beat to beat mode), breathing movements, and airflow were made on 66 preterm infants (median gestational age 34 weeks, range 25-36) who had reached term (37 weeks) and were ready for discharge from the special care baby unit. No infant was given additional inspired oxygen during the study. The median baseline SaO2 was 99-4% (range 88-9-100% In the present study, the same techniques have been applied to a group of preterm infants who were studied when they were ready for discharge from the special care baby unit and had reached at least 37 weeks' gestation. Two specific questions were asked: what is the influence of gestational age on the pattern of oxygenation, and (based on our study of term infants4) how does oxygenation differ between full term and preterm infants?Patients and methods Between August 1986 and July 1987 all preterm infants who were born at three maternity hospitals and who received special care immediately after birth had overnight tape recordings made of selected physiological variables. The study was carried out when infants were assessed as ready for discharge, and only on those who were considered to have a good prognosis for survival. A total of 305 infants fulfilled the criteria, and 261 (86%) had parental consent for the investigation. The project was approved by the hospitals' ethics committees. For the purpose of this study, all 72 infants with gestational ages of 37 weeks or more at the time of discharge, and who underwent their recordings within the three days before discharge, were included in the analysis.All 72 infants underwent 12 hour overnight recordings of arterial oxygen saturation (SaO2) (Nellcor N100 with new software equivalent to N200 and specially modified to provide beat to beat data); each photoplethysmographic pulse waveform from a pulse oximeter (for the validation of the saturation signals); breathing movements from a volume expansion capsule (Graseby) or from respiratory inductance plethysmography (Studley Data Systems); and nasal airflow either through a thermistor (Yellow Springs Instruments) or from expired carbon dioxide sampling (Engstrom Eliza). The recordings were stored on tape (Racal FM4) and subsequently printed onto graph paper by an ink jet recorder at 3-2 mm/second. As the study was prospective and non-invasive the recordings were not used for clinical management.Six recordings (8%) gave poor quality oxygen saturation signals throughout and were removed from the study. Of the remaining 66 recordings, 31 (47%) were done on the last day before discharge, 26 (39%) two days, and eight (12%)

Aim: To review treatments for apnoea of prematurity (AOP). Methods: Literature Review and description of personal practice. Results: Provided that symptomatic apnoea has been ruled out, interventions to improve AOP can be viewed as directed at one of three underlying mechanisms: (i) a reduced work of breathing [e.g. prone positioning, nasal continuous positive airway pressure (CPAP)], (ii) an increased respiratory drive (e.g. caffeine), and (iii) an improved diaphragmatic function (e.g. branched-chain amino acids).Most options currently applied, however, have not yet been shown to be effective and ⁄ or safe, except for prone, head-elevated positioning, synchronized nasal ventilation ⁄ CPAP, and caffeine.Conclusion: Treatment usually follows an incremental approach, starting with positioning, followed by caffeine (which should be started early, at least in infants <1250 g), and nasal ventilation or CPAP via variable flow systems that reduce work of breathing. From a research point of view, we most urgently need data on the frequency and severity of bradycardia and intermittent hypoxia that can yet be tolerated without putting an infant at risk of impaired development or retinopathy of prematurity.