Cof Kamlin

Defining the reference range for oxygen saturation for infants after birth.

OBJECTIVE: The goal was to define reference ranges for pulse oxygen saturation (Spo2) values in the first 10 minutes after birth for infants who received no medical intervention in the delivery room. METHODS: Infants were eligible if a member of the research team was available to record Spo2 immediately after birth. Infants were excluded if they received supplemental oxygen or any type of assisted ventilation. Spo2 was measured with a sensor applied to the right hand or wrist as soon as possible after birth; data were collected every 2 seconds. RESULTS: We studied 468 infants and recorded 61650 Spo2 data points. The infants had a mean ± SD gestational age of 38 ± 4 weeks and birth weight of 2970 ± 918 g. For all 468 infants, the 3rd, 10th, 50th, 90th, and 97th percentile values at 1 minute were 29%, 39%, 66%, 87%, and 92%, respectively, those at 2 minutes were 34%, 46%, 73%, 91%, and 95%, and those at 5 minutes were 59%, 73%, 89%, 97%, and 98%. It took a median of 7.9 minutes (interquartile range: 5.0–10 minutes) to reach a Spo2 value of >90%. Spo2 values for preterm infants increased more slowly than those for term infants. We present percentile charts for all infants, term infants of ≥37 weeks, preterm infants of 32 to 36 weeks, and extremely preterm infants of <32 weeks. CONCLUSION: These data represent reference ranges for Spo2 in the first 10 minutes after birth for preterm and term infants.

Oxygen saturation and heart rate during delivery room resuscitation of infants <30 weeks gestation with air or 100% oxygen.

Background: Because of concerns about harmful effects of 100% oxygen on newborn infants, air has started to be used for resuscitation in the delivery room. Objective: To describe changes in preductal oxygen saturation (Spo2) and heart rate (HR) in the first 10 min after birth in very preterm infants initially resuscitated with 100% oxygen (OX100) or air (OX21). Patients and methods: In July 2006, policy changed from using 100% oxygen to air. Observations of Spo2 and HR before and after the change were recorded whenever a member of the research team was available to attend the birth. Results: There were 20 infants in the OX100 group and 106 in the OX21 group. In the OX100 group, Spo2 had risen to a median of 84% after 2 min and 94% by 5 min. In the OX21 group, median Spo2 was 31% at 2 min and 54% at 5 min. In the OX21 group, 92% received supplemental oxygen at a median of 5 min; the Spo2 rose to a median of 81% by 6 min. In the first 10 min after birth, 80% and 55% of infants in the OX100 and OX21 groups, respectively, had an Spo2 ⩾95%. Increases in HR over the first 10 min were very similar in the two groups. Conclusions: Most very preterm infants received supplemental oxygen if air was used for the initial resuscitation. In these infants, the use of backup 100% oxygen and titration against Spo2 resulted in a similar course to “normal” term and preterm infants. Of the infants resuscitated with 100% oxygen, 80% had Spo2 ⩾95% during the first 10 min. The HR changes in the two groups were very similar.

Changes in heart rate in the first minutes after birth

The normal range of heart rate (HR) in the first minutes after birth has not been defined. Objective To describe the HR changes of healthy newborn infants in the delivery room (DR) detected by pulse oximetry. Study Design All inborn infants were eligible and included if a member of the research team attended the birth. Infants were excluded if they received any form of medical intervention in the DR including supplemental oxygen, or respiratory support. HR was measured using a pulse oximeter (PO) with the sensor applied to the right hand or wrist immediately after birth. PO data (oxygen saturation, HR and signal quality) were downloaded every 2 sec and analysed only when the signal had no alarm messages (low IQ signal, low perfusion, sensor off, ambient light). Results Data from 468 infants with 61 650 data points were included. Infants had a mean (range) gestational age of 38 (25–42) weeks and birth weight 2970 (625–5135) g. At 1 min the median (IQR) HR was 96 (65–127) beats per min (bpm) rising at 2 min and 5 min to 139 (110–166) bpm and 163 (146–175) bpm respectively. In preterm infants, the HR rose more slowly than term infants. Conclusions The median HR was <100 bpm at 1 min after birth. After 2 min it was uncommon to have a HR <100 bpm. In preterm infants and those born by caesarean section the HR rose more slowly than term vaginal births.

Predicting successful extubation of very low birthweight infants.

Objective: To determine the accuracy of three tests used to predict successful extubation of preterm infants. Study design: Mechanically ventilated infants with birth weight <1250 g and considered ready for extubation were changed to endotracheal continuous positive airway pressure (ET CPAP) for three minutes. Tidal volumes, minute ventilation (V˙e), heart rate, and oxygen saturation were recorded before and during ET CPAP. Three tests of extubation success were evaluated: (a) expired V˙e during ET CPAP; (b) ratio of V˙e during ET CPAP to V˙e during mechanical ventilation (V˙e ratio); (c) the spontaneous breathing test (SBT)—the infant passed this test if there was no hypoxia or bradycardia during ET CPAP. The clinical team were blinded to the results, and all infants were extubated. Extubation failure was defined as reintubation within 72 hours of extubation. Results: Fifty infants were studied and extubated. Eleven (22%) were reintubated. The SBT was the most accurate of the three tests, with a sensitivity of 97% and specificity of 73% and a positive and negative predictive value for extubation success of 93% and 89% respectively. Conclusion: The SBT used just before extubation of infants <1250 g may reduce the number of extubation failures. Further studies are required to establish whether the SBT can be used as the primary determinant of an infant’s readiness for extubation.

Pulse oximetry for monitoring infants in the delivery room: a review

During the first few minutes of life, oxygen saturation (saturation by pulse oximetry, SpO2) increases from intrapartum levels of 30–40%.1 In algorithms for neonatal resuscitation published by the International Liaison Committee for Resuscitation,2 European Resuscitation Council3 and Australian Resuscitation Council,4 clinical assessment of an infant’s colour (a measure of oxygenation) and heart rate are used as major action points. However, studies have shown that clinical assessment of colour during neonatal transition is unreliable.5,6 O’Donnell et al 6 showed that the SpO2 at which observers perceived infants to be pink varied widely, ranging from 10% to 100%. Assessing colour is difficult and therefore is a poor proxy for tissue oxygenation during the first few minutes of life. Kattwinkel7 suggested pulse oximetry may help achieve normoxia in the delivery room. The American Heart Association8 suggests that “administration of a variable concentration of oxygen guided by pulse oximetry may improve the ability to achieve normoxia more quickly”. Although “normoxia” and an acceptable time to achieve this during neonatal transition have not been defined, Leone and Finer9 advocate a target “SpO2 of 85 to 90% by three minutes after birth for all infants except in special circumstances”—for example, diaphragmatic hernia or cyanotic congenital heart disease. International surveys show that oximetry is increasingly used during neonatal resuscitation.10,11 To date, there are no evidence-based guidelines for using oximetry to measure an infant’s SpO2 and to guide interventions during neonatal transition after birth. We reviewed the literature to evaluate the evidence on the use of SpO2 measurements immediately after birth. Pulse oximetry measures SpO2 continuously and non-invasively, without the need for calibration, and correlates closely with arterial oxygen saturation.12 Pulse oximetry is based on the red and infrared light-absorption …

Neonatal resuscitation 1: a model to measure inspired and expired tidal volumes and assess leakage at the face mask

Background: Neonatal resuscitation is a common and important intervention, and adequate ventilation is the key to success. In the delivery room, positive pressure ventilation is given with manual ventilation devices using face masks. Mannequins are widely used to teach and practise this technique. During both simulated and real neonatal resuscitation, chest excursion is used to assess tidal volume delivery, and leakage from the mask is not measured. Objective: To describe a system that allows measurement of mask leakage and estimation of tidal volume delivery. Methods: Respiratory function monitors, a modified resuscitation mannequin, and a computer were used to measure leakage from the mask and to assess tidal volume delivery in a model of neonatal resuscitation. Results: The volume of gas passing through a flow sensor was measured at the face mask. This was a good estimate of the tidal volume entering and leaving the lung in this model. Gas leakage between the mask and mannequin was also measured. This occurred principally during inflation, although gas leakage during deflation was seen when the total leakage was large. A volume of gas that distended the mask but did not enter the lung was also measured. Conclusion: This system can be used to assess the effectiveness of positive pressure ventilation given using a face mask during simulated neonatal resuscitation. It could be useful for teaching neonatal resuscitation and assessing ventilation through a face mask.

Sustained Inflations: Comparing Three Neonatal Resuscitation Devices

Background: Some national resuscitation guidelines advocate using sustained initial inflations (2–3 s) for babies requiring resuscitation. Inflation times ≧10 s have been used for preterm infants. Objectives: This study examines the ability of operators of varying experience to provide a sustained inflation using three different manual ventilation devices. Methods: We compared a self-inflating bag, a flow-inflating bag and a pressure-limited T-piece device. Fifty clinical staff members from five professional groups gave a sustained inflation with a target peak pressure of 30 cm H2O and target duration of 10 s to an internal leak-free manikin. We measured peak inflating pressure (PIP) and mean inflating pressure (MIP) during the sustained inflation, and the duration of inflating pressure (IP) >20 and 25 cm H2O. Results: Median (IQR) duration of IP >25 cm H2O was: self-inflating bag 2.5 s (0.8–5.7), flow-inflating bag 10.6 s (8.4–12.9) and the T-piece 10.7 s (8.9–11.9). There was a weak correlation between experience using a self-inflating bag and longer inflation times (R = 0.290, p = 0.041). When compared with the T-piece, the flow-inflating bag had lower mean MIP (27.0 ± 1.8 vs. 28.8 ± 2.0 cm H2O) and higher mean PIP (32.3 ± 3.7 vs. 29.8 ± 1.8 cm H2O). There were no differences in performance between operator groups. Conclusion: The T-piece provided consistent PIP during a single 10 s sustained inflation with less variation in pressure compared with the flow-inflating bag. Sustained inflations >3 s were difficult to achieve with a self-inflating bag.

Comparison of heart rate and oxygen saturation measurements from Masimo and Nellcor pulse oximeters in newly born term infants.

To compare heart rate (HR) measurements from Masimo and Nellcor pulse oximeters (POs) against HR measured via a three lead electrocardiograph (ECG) (HRECG). We also compared peripheral oxygen saturation (SpO2) measurements between Nellcor and Masimo oximeters.

A Trial Of Spontaneous Breathing To Determine The Readiness For Extubation In Very Low Birth Weight Infants; A Prospective Evaluation

Extubation failure in premature infants is common. A spontaneous breathing trial (SBT) was prospectively evaluated to determine timing of extubation. Compared with historical controls, infants were extubated at significantly higher ventilator rates and airway pressures using the SBT. No differences in rates of bronchopulmonary dysplasia or duration of ventilation were seen.

Videolaryngoscopy to Teach Neonatal Intubation: A Randomized Trial

BACKGROUND: Neonatal endotracheal intubation is a necessary skill. However, success rates among junior doctors have fallen to <50%, largely owing to declining opportunities to intubate. Videolaryngoscopy allows instructor and trainee to share the view of the pharynx. We compared intubations guided by an instructor watching a videolaryngoscope screen with the traditional method where the instructor does not have this view. METHODS: A randomized, controlled trial at a tertiary neonatal center recruited newborns from February 2013 to May 2014. Eligible intubations were performed orally on infants without facial or airway anomalies, in the delivery room or neonatal intensive care, by doctors with <6 months’ tertiary neonatal experience. Intubations were randomized to having the videolaryngoscope screen visible to the instructor or covered (control). The primary outcome was first-attempt intubation success rate confirmed by colorimetric detection of expired carbon dioxide. RESULTS: Two hundred six first-attempt intubations were analyzed. Median (interquartile range) infant gestation was 29 (27 to 32) weeks, and weight was 1142 (816 to 1750) g. The success rate when the instructor was able to view the videolaryngoscope screen was 66% (69/104) compared with 41% (42/102) when the screen was covered (P < .001, OR 2.81, 95% CI 1.54 to 5.17). When premedication was used, the success rate in the intervention group was 72% (56/78) compared with 44% (35/79) in the control group (P < .001, OR 3.2, 95% CI 1.6 to 6.6). CONCLUSIONS: Intubation success rates of inexperienced neonatal trainees significantly improved when the instructor was able to share their view on a videolaryngoscope screen.