Neonatal presentation of incontinentia pigmenti with a family history extending over four generations--a case report.

We report a case of Incontinentia pigmenti (IP). A day 2 female presented to the special care nursery with seizures. EEG showed multifocal epileptiform discharges and cranial MRI revealed extensive cerebral infarction. A rash appeared shortly after birth. Eye examination revealed changes of IP. There is a strong family history of IP. Genetic testing excluded the most common mutation. Follow-up reveals significant development delay.

Ventilator-delivered mask ventilation compared with three standard methods of mask ventilation in a manikin model.

BACKGROUND: Little is known regarding the variations in effective ventilation during bag and mask resuscitation with standard methods compared with that delivered by ventilator-delivered mask ventilation (VDMV). AIM: To measure the variations in delivered airway pressure, tidal volume (TV), minute ventilation (MV) and inspiratory time during a 3-min period of mask ventilation comparing VDMV with three commonly used hand-delivered methods of bag and mask ventilation: Laerdal self-inflating bag (SIB); anaesthetic bag and T-piece Neopuff. METHODS: A modified resuscitation manikin was used to measure variation in mechanical ventilation during 3-min periods of mask ventilation. Thirty-six experienced practitioners gave positive pressure mask ventilation targeting acceptable chest wall movement with a rate of 60 inflations/min and when pressures could be targeted or set, a peak inspiratory pressure (PIP) of 18 cm water, positive end-expiratory pressure (PEEP) of 5 cm water, for 3 min with each of the four mask ventilation methods. Each mode was randomly sequenced. RESULTS: A total of 21 136 inflations were recorded and analysed. VDMV achieved PIP and PEEP closest to that targeted and significantly lower variation in all measured parameters (p<0.001) other than with PIP. SIB delivered TV and MV over twice that delivered by VDMV and Neopuff. CONCLUSION: During 3-min periods of mask ventilation on a manikin, VDMV produced the least variation in delivered ventilation. SIB produced wide variation and unacceptably high TV and MV in experienced hands.

Mask leak in one-person mask ventilation compared to two-person in newborn infant manikin study.

AIM: To compare a new two-person method (four hands) of delivering mask ventilation with a standard one-person method using the Laerdal self-inflating bag (SIB) and the Neopuff (NP) infant resuscitator in a manikin model. BACKGROUND: Recent studies of simulated neonatal resuscitation using bag and mask ventilation techniques have shown facemask leak levels of 55-57% in expert hands. METHODS: 48 participants were randomly paired and instructed to give mask ventilation for a 2-min period as single-person resuscitators, then as two-person paired resuscitators at set pressures for NP and set parameters for SIB. Airway pressure, flow, inspiratory tidal volume, expiratory tidal volume and mask leak were recorded. RESULTS: A total of 21 578 inflations were recorded and analysed. For SIB, mask leak was greater (11.5%) with single-person compared to two-person (5.4%; mean difference 6.1%, 95% CI 1.5 to 10.7, p<0.01). For NP, mask leak was greater for single-person (22.2%) compared to two-person (9.1%; mean difference 13.1% 95% CI 3.6 to 22.6, p<0.01). For single-person mask ventilation, mask leak was greater with NP (22.2%) compared to SIB (11.5%; mean difference 10.7%, 95% CI 1.4 to 19.7, p<0.01). For two-person mask ventilation, mask leak was greater for NP (9.1%) compared to SIB (5.4%; mean difference 3.7%, 95% CI 0.1 to 6.4, p<0.05). CONCLUSIONS: Two-person mask ventilation technique reduces mask leak by approximately 50% compared to the standard one-person mask ventilation method. NP mask ventilation has higher mask leak than Laerdal SIB for both single- and two-person technique mask ventilation.

Radiofrequency catheter ablation in a haemodynamically compromised premature neonate with hydrops fetalis.

A preterm infant was born at 35 weeks gestation after failed antenatal antiarrhythmic therapy. The infant had an incessant supraventricular tachycardia, impaired ventricular function and hypotension and failed to respond to adenosine, cardioversion and intravenous amiodarone. After resuscitation from cardiovascular collapse, a successful radiofrequency catheter ablation (RFA) of a left free wall atrioventricular pathway was performed at 24 h of age without extracorporeal support. The infant is normal on follow up at 12 months of age. Whilst most fetal and neonatal supraventricular tachyarrhythmias respond to antiarrhythmic medications and RFA is not required, this is the earliest RFA to be performed on a premature infant when antiarrhythmics have failed.

Variability in cerebral blood flow velocity: observations over one minute in preterm babies.

Cerebral blood flow velocity (CBFV) was measured using Doppler ultrasound on the first day of life in a consecutively admitted cohort of 52 very low birthweight infants. Recordings were made for a period of 1 min. The coefficient of variation for the area under the curve of 20 successive cardiac cycles was calculated, and a 20 cycle moving window then applied to the whole recording. This showed that the coefficient of variation varied widely during 1 min in any individual, the range being from 2% to 28% (median 8%). There was a strong correlation between the variability in CBFV and that in systemic blood pressure (BP). Variability in CBFV was significantly higher in babies with hypotensive episodes (P = 0.026). Babies who died had a higher maximum coefficient of variation than those who survived (P = 0.05), but we were unable to confirm any association with brain injury or patent ductus arteriosus.

Comparison of cerebral blood flow velocity estimation with cranial ultrasound imaging for early prediction of outcome in preterm infants.

Seventy-four low birth weight infants underwent serial measurements of cerebral blood flow velocity (CBFV) using Doppler ultrasound together with ultrasound imaging of the brain. Surviving infants were examined and assessed using the Bayley scales of mental and motor development at 18 months post-term. There were no significant differences in mean CBFV between normal and impaired infants. Infants with abnormal neurological signs (n = 6) or developmental delay (n = 3) did not show the usual steady rise in CBFV during the first few days of life. Four of nine had a rise, then a fall in CBFV compared with 4 of 31 with complete data in the normal group. This difference is significant (chi 2 = 4.3, p = 0.03). The magnitude of the percentage increase between day 1 and day 3 was also smaller in the abnormal group (median 0% vs. 39%, Mann-Whitney p = 0.03). A structural abnormality seen on the cranial ultrasound image was a better predictor of adverse outcome than an abnormal CBFV pattern, with a better sensitivity and specificity (66% and 97% for imaging compared to 44% and 87% for CBFV). The addition of serial ultrasound Doppler measurements of CBFV did not improve the prediction of outcome obtained using ultrasound imaging alone.

A model of the instantaneous pressure-velocity relationships of the neonatal cerebral circulation.

The instantaneous relationship between arterial blood pressure (BP) and cerebral blood flow velocity (CBFV), measured with Doppler ultrasound in the anterior cerebral artery, is represented by a vascular waterfall model comprising vascular resistance, compliance, and critical closing pressure. One min recordings obtained from 61 low birth weight newborns were fitted to the model using a least-squares procedures with correction for the time delay between the BP and CBFV signals. A sensitivity analysis was performed to study the effects of low-pass filtering (LPF), cutoff frequency, and noise on the estimated parameters of the model. Results indicate excellent fitting of the model (F-test, p < 0.0001) when the BP and CBFV signals are LPF at 7.5 Hz. Reconstructed CBFV waveforms using the BP signal and the model parameters have a mean correlation coefficient of 0.94 with the measured flow velocity tracing (N = 232 epochs). The model developed can be useful for interpreting clinical findings and as a framework for research into cerebral autoregulation.

Factors associated with respiration induced variability in cerebral blood flow velocity.

A consecutive cohort of 73 very low birthweight infants was studied to determine the presence or absence of beat to beat variability in the velocity of blood flow in the cerebral circulation and its relation with respiration. One minute epochs of information included recordings of cerebral blood flow velocity estimated with Doppler ultrasound, blood pressure, spontaneous respiratory activity, and ventilator cycling. Fourier transformation was used to resolve the frequencies present within the one minute epochs and to classify the cerebral blood flow velocity as showing the presence or absence of any respiratory associated variability. A total of 249 recordings was made on days 1, 2, 3, and 7. Forty seven infants showed respiratory variability in cerebral blood flow velocity on 97 occasions, usually during the first day of life. The infants with respiratory associated variability were of lower gestational age and when the respiratory associated variability was present they were more likely to be ventilated and receiving higher inspired oxygen; these associations were shown to be independent of gestational age. There was no significant independent association with brain injury, cerebral blood flow velocity (cm/s), or blood pressure (mm Hg). The findings suggest that artificial ventilation may entrain normal respiratory associated variability in the cerebral circulation but do not provide evidence that it is harmful.

Postnatal evolution of slow variability in cerebral blood flow velocity.

The evolution of low frequency variability in cerebral blood flow velocity (CBFV) was examined in 30 consecutive admissions of very low birthweight babies. Measurement of CBFV was made on the first day of life and at weekly intervals until discharge. Altogether 133 recordings were subjected to visual classification and described as showing presence or absence of variability at a frequency between 1 and 5/minute. Amplitude of variability was expressed as the largest variation in peak systolic velocity as a percentage of the maximum systolic change. Slow variability was usually obvious and was sometimes present for only part of the minute recorded. There was a significant trend for decreased incidence of slow variability in relation to both postconceptional and postnatal ages. Amplitude of slow variability was also damped with increasing age. Slow variability appeared to be unrelated to the type of sedation, severity of illness, or intracranial pathology; it may be a normal phenomenon in which damping occurs as the autonomic nervous system matures.

Possible causes linking asphyxia, thick meconium and respiratory distress.

The cause of fetal distress and neonatal respiratory distress (RD) in association with meconium-stained liquor is not always clear. To clarify this, a prospective study was undertaken in a tertiary referral maternity hospital for 1 year. In all infants born after meconium-stained liquor who developed RD, evidence was sought for 1) fetal distress (from the cardiotocograph (CTG), the cord blood pH, the Apgar score and the asphyxial complications in the neonate) 2) causes of fetal distress (including maternal risk factors, fetal infection and fetal malnutrition) 3) causes of respiratory distress (including meconium aspiration syndrome (MAS), persistent pulmonary hypertension of the newborn (PPHN) and infection). Of 4,026 livebirths, 717 (17.8%) had meconium-stained liquor and 44 term and 5 preterm infants developed RD. In the 44 term infants, there was frequent evidence of fetal distress possibly caused by previously unrecognized factors such as fetal malnutrition with reduced neonatal skinfold thickness in 35% triceps and 41% subscapular measurements, and histological chorioamnionitis (CA) in 74%. The cause for respiratory distress was identified in only 48% of infants, and included clinical evidence of PPHN (41%), MAS (16%) and infection (2%). However in preterm infants, 80% had definite or suspected infection. The findings indicate that fetal distress is common in infants who develop respiratory distress after meconium-stained liquor. A role for histological CA and reduced nutrition in the fetus, as factors contributing to the vulnerability of the term infant to intrapartum fetal distress, is suggested.