Mmoloki Kenosi

Current research suggests that the future looks brighter for cerebral oxygenation monitoring in preterm infants.

Brain injuries remain a significant problem for preterm infants, despite extensive physiological monitoring. Near infrared spectroscopy (NIRS) monitoring in the neonatal intensive care unit has to date remained limited to research activities.

Perfusion index in the preterm infant immediately after birth

AIM To evaluate PI in preterm infants during the first 10 min of life. DESIGN/METHODS An observational study was conducted in the delivery room on preterm infants (less than 32 week gestation). PI values were obtained from a pre ductal saturation probe placed on the right wrist. Analysis was performed on the first 10 min of data to investigate the correlation of PI with gestational age, heart rate, blood pressure, and lactate values. RESULTS 33 infants with a median gestational age of 29 wks (IQR, 26-30 wks) and median birth weight of 1205 g (IQR, 925-1520 g) were included for analysis. The overall median PI value for the first 10 min was 1.3 (IQR, 0.86-1.68). There was no significant correlation found between delivery room PI and gestational age(r=0.28, 95% CI: -0.09, 0.59), lactate levels (r=-0.25, 95% CI: -0.62, 0.18) and blood pressure values (r=-0.18, 95% CI: -0.46, 0.20). An average correlation value of r=-0.417 (95% CI: - 0.531, -0.253) was found between PI and heart rate values. There was no statistical difference between the median of the median PI value over the first 5 min of life compared to the second 5 min (p=0.22). Variability, as quantified by the IQR, was higher in the first 5 min compared to the second 5 min: median of 0.5(IQR, 0.27, 0.92) vs 0.2(IQR, 0.10, 0.30) (p<0.00). CONCLUSIONS Delivery room PI values are easily obtained, however, have significant variability over the first 5 min of life and may add little to delivery room assessment.

Effects of Fractional Inspired Oxygen on Cerebral Oxygenation in Preterm Infants following Delivery

OBJECTIVES To explore regional cerebral oxygen saturations (rcSO2) in preterm neonates initially stabilized with 0.3 fractionated inspired oxygen (FiO2) concentrations. We hypothesized that those infants who received >0.3 FiO2 during stabilization following delivery would have relatively higher rcSO2 postdelivery compared with those stabilized with a lower FiO2. STUDY DESIGN A single center prospective observational study of 47 infants born before 32 weeks. Using near infrared spectroscopy, rcSO2 values were recorded immediately after birth. All preterm infants were initially given 0.3 FiO2 and were divided into 2 groups according to subsequent FiO2 requirements of either ≤0.3 or >0.3 FiO2. Using a mixed-effects model, we compared the difference between the groups over time. Also, the area measures below 55% (hypoxia) and above 85% (hyperoxia) were compared between the groups. RESULTS The mean (SD) gestation was 29.4 (1.6) weeks and the mean (SD) weight was 1.3 (0.4) kg. Less than one-half of the infants (20/45; 43%) required ≤0.3 FiO2. In the delivery suite, the median (IQR) rcSO2 in the low and high FiO2 groups were 81% (66%-86%) and 72% (62%-86%), respectively. Patients in the high FiO2 group had a larger rcSO2 area below 55% (P = .01). There was a significant difference in rcSO2 between the groups (P < .05), with the low group having higher rcSO2 values initially, but this difference changed over time. In the neonatal intensive care unit (NICU), rcSO2 values were lower by 7.1% (CI 12.13 to 2.06%) P = .008 in the high FiO2 group. CONCLUSIONS Infants given >0.3 FiO2 had more cerebral hypoxia than infants requiring ≤0.3 FiO2 but no difference in the degree of cerebral hyperoxia, both in the delivery suite and the NICU. This suggests that a more rapid increase in oxygen titration maybe be required initially for preterm infants.

Auscultate, Palpate and Tap : Time to Re‐Evaluate

To determine the accuracy of current methods of heart rate (HR) assessment.

Quantitative or qualitative carbon dioxide monitoring for manual ventilation: a mannequin study.

To compare the effectiveness of an in‐line EtCO2 detector (DET) and a quantitative EtCO2 detector (CAP), both attached to a t‐piece resuscitator, during PPV via a face mask.

Delivery room end tidal CO2 monitoring in preterm infants <32 weeks

Objectives To determine the feasibility of end tidal (EtCO2) monitoring of preterm infants in the delivery room, to determine EtCO2 levels during delivery room stabilisation, and to examine the incidence of normocapnia (5–8 kPa) on admission to the neonatal intensive care unit in the EtCO2 monitored group compared with a historical cohort without EtCO2 monitoring. Patients and methods Preterm infants (<32 weeks) were eligible for inclusion in this observational study. The evolution of EtCO2 values immediately after delivery was assessed and linear least-squares methods were used to fit a line to EtCO2 recordings. The partial pressure of CO2 in blood (PCO2) from the infants who received EtCO2 monitoring was compared with a historical cohort without EtCO2 monitoring. Results EtCO2 monitoring was feasible in the delivery room. EtCO2 values were successfully obtained in 39 (88.7%) of the 44 infants included in the study. EtCO2 gradually increased over the first 4 min. Intubated infants had higher EtCO2 values compared with infants who were not intubated, with median (IQR) values of 4.7 (3.3–8.4) kPa versus 3.2 (2.6–4.2) kPa (p=0.05). No difference was found between the proportions of PCO2 values within the range of normocapnia among infants who received EtCO2 monitoring compared with those who did not (56.8% vs 47.9%, p=0.396). Conclusions Delivery room EtCO2 monitoring is feasible and safe. EtCO2 values obtained after birth reflect the establishment of functional residual capacity and effective ventilation. The potential short-term and long-term consequences of EtCO2 monitoring should be established in randomised controlled trials.

Monitoring cerebral oxygenation of preterm infants using a neonatal specific sensor

IntroductionCerebral oxygenation (rcSO2) monitoring in preterm infants may identify periods of cerebral hypoxia or hyperoxia. We hypothesised that there was a relationship between rcSO2 values and short term outcome in infants of GA < 32weeks.MethodsRcSO2 values were recorded for the first 48 h of life using an INVOS monitor with a neonatal sensor. The association between cranial ultrasound scan measured brain injury and rcSO2 was assessed.Results120 infants were included. Sixty-nine percent (83) of infants had a normal outcome (no IVH, no PVL, and survival at 1 month); less than one-quarter, 22% (26), had low grade IVH 1 or 2 (moderate outcome); and 9% (11) of infants had a severe outcome (IVH ≥ 3, PVL or died before 1 month age). rcSO2 values were lower for infants GA < 28weeks when compared with those GA 28–32, p < 0.001. There was no difference in absolute rcSO2 values between the three outcome groups but a greater degree of cerebral hypoxia was associated with preterm infants who had low grade 1 or 2 IVH.ConclusionInfants of GA < 28 weeks have lower cerebral oxygenation in the first 2 days of life. A greater degree of hypoxia was seen in infants with grade 1 or 2 haemorrhage. Normative ranges need to be gestation specific.

Features of cerebral oxygenation detects brain injury in premature infants

Babies born prematurely can develop brain injury within days after birth. Early identification of high-risk infants enables appropriate clinical care to mitigate potential lifelong disabilities. Near infra-red spectroscopy is an established technology that can provide continuous measurements of cerebral oxygen saturation (rcSO2) over this critical period. We develop a feature set of the rcSO2 signal for the purpose of detecting brain injury. Our feature set contains amplitude, spectral, and fractal dimension features within 5 frequency bands. Features are combined in a support vector machine (SVM) and performance is assessed within a cross-validation procedure. Using a cohort of 47 infants of <;32 weeks of gestation, we find significant (p <; 0.05) features of amplitude in the frequency band 0.9-3.6 mHz and a fractal dimension measure in the frequency band 1.8-3.6 mHz. The SVM has an area-under the receiver operator characteristic (AUC) of 0.75 with sensitivity-specificity values of 67-77%. These moderate results highlight the potential for quantitative analysis of rcSO2 to detect brain injury and thus enable early identification of high-risk infants.

Corrective ventilation strategies in delivery room resuscitation of preterm infants

Corrective ventilation strategies (CVS) during neonatal resuscitation and stabilisation (R&S) are taught through the MRSOPA mnemonic: Mask adjustment, Repositioning airway, Suctioning, Opening the mouth, Increasing inspiratory Pressure, and Alternative airway. The aim was to examine the use of CVS and to investigate the relationship between MRSOPA strategies and intubation of very preterm infants <32 weeks’ gestation in the delivery room.

Delivery room end tidal CO2monitoring in preterm infants <32 weeks

Objectives To determine the feasibility of end tidal (EtCO2) monitoring of preterm infants in the delivery room, to determine EtCO2 levels during delivery room stabilisation, and to examine the incidence of normocapnia (5–8 kPa) on admission to the neonatal intensive care unit in the EtCO2 monitored group compared with a historical cohort without EtCO2 monitoring. Patients and methods Preterm infants (<32 weeks) were eligible for inclusion in this observational study. The evolution of EtCO2 values immediately after delivery was assessed and linear least-squares methods were used to fit a line to EtCO2 recordings. The partial pressure of CO2 in blood (PCO2) from the infants who received EtCO2 monitoring was compared with a historical cohort without EtCO2 monitoring. Results EtCO2 monitoring was feasible in the delivery room. EtCO2 values were successfully obtained in 39 (88.7%) of the 44 infants included in the study. EtCO2 gradually increased over the first 4 min. Intubated infants had higher EtCO2 values compared with infants who were not intubated, with median (IQR) values of 4.7 (3.3–8.4) kPa versus 3.2 (2.6–4.2) kPa (p=0.05). No difference was found between the proportions of PCO2 values within the range of normocapnia among infants who received EtCO2 monitoring compared with those who did not (56.8% vs 47.9%, p=0.396). Conclusions Delivery room EtCO2 monitoring is feasible and safe. EtCO2 values obtained after birth reflect the establishment of functional residual capacity and effective ventilation. The potential short-term and long-term consequences of EtCO2 monitoring should be established in randomised controlled trials.