Clarissa Pieper

Induced Hypothermia for Infants With Hypoxic- Ischemic Encephalopathy Using a Servo-Controlled Fan: An Exploratory Pilot Study

OBJECTIVE. Several trials suggest that hypothermia is beneficial in selected infants with hypoxic-ischemic encephalopathy. However, the cooling methods used required repeated interventions and were either expensive or reported significant temperature variation. The objective of this pilot study was to describe the use, efficacy, and physiologic impact of an inexpensive servo-controlled cooling fan blowing room-temperature air. PATIENTS AND METHODS. A servo-controlled fan was manufactured and used to cool 10 infants with hypoxic-ischemic encephalopathy to a rectal temperature of 33°C to 34°C. The infants were sedated with phenobarbital, but clonidine was administered to some infants if shivering or discomfort occurred. A servo-controlled radiant warmer was used simultaneously with the fan to prevent overcooling. The settings used on the fan and radiant warmer differed slightly between some infants as the technique evolved. RESULTS. A rectal temperature of 34°C was achieved in a median time of 58 minutes. Overcooling did not occur, and the mean temperature during cooling was 33.6°C ± 0.2°C. Inspired oxygen requirements increased in 6 infants, and 5 infants required inotropic support during cooling, but this was progressively reduced after 1 to 2 days. Dehydration did not occur. Five infants shivered when faster fan speeds were used, but 4 of the 5 infants had hypomagnesemia. Shivering was controlled with clonidine in 4 infants, but 1 infant required morphine. CONCLUSIONS. Servo-controlled fan cooling with room-temperature air, combined with servo-controlled radiant warming, was an effective, simple, and safe method of inducing and maintaining rectal temperatures of 33°C to 34°C in sedated infants with hypoxic-ischemic encephalopathy. After induction of hypothermia, a low fan speed facilitated accurate temperature control, and warmer-controlled rewarming at 0.2°C increments every 30 minutes resulted in more appropriate rewarming than when 0.5°C increments every hour were used.

Is nCPAP of Value in Extreme Preterms with No Access to Neonatal Intensive Care

This prospective study was undertaken to investigate the efficacy of nasal continuous positive airway pressure (nCPAP) in a group of extremely small infants denied access to a neonatal intensive care unit (NICU) in South Africa. Consecutive infants weighing less than 1200 g and/or of a gestational age below 28 weeks admitted to the neonatal ward with respiratory distress syndrome (RDS), and who were refused admission to the NICU, received either nCPAP (Infant Flow System E.M.E., UK) of headbox oxygen. Of 22 infants, 11 infants were included in the treatment group (nCPAP) and 10 in the control group. Within the first 24 h, two infants (18 per cent) in the nCPAP group and eight infants (80 per cent) in the control group died (p = 0.007) (survival OR = 18; RR = 4.09). A statistically significant improvement in the arterial-alveolar (a/A) oxygen ratio occurred in the nCPAP group between postnatal day 1 and day 3 of life (0.17 vs. 0.36; p < 0.005). Neonatal complications occurred in six (55 per cent) infants who survived the first 24 h of life. Eighty per cent of the infants with intraventricular haemorrhage (IVH) died, as well as all the infants who were born before arrival at the hospital. At the time of discharge from hospital, 45 per cent (five infants) in the nCPAP group survived vs. 20 per cent (two infants) in the control group. The neurodevelopmental outcome of six of the surviving seven infants were evaluated at 1 year of corrected age. The neurodevelopmental outcome as assessed by the Griffith Score was within normal limits in all infants. One infant has sensorineural deafness and one is deaf and has a possible mild spastic diplegia (both in the treatment group). We conclude that nCPAP significantly improves the short-term survival of very low birth-weight (VLBW) infants with moderate to severe respiratory distress syndrome who could not be admitted to intensive care. nCPAP significantly improves the a/A oxygen ratio between day 1 and day 3 of life.

Comparison of a New Desktop Spirometer (Diagnosa®) with a Laboratory Spirometer

Background: The Diagnosa is a fully integrated system, able to determine spirometry, ECG, blood pressure and body composition. Real time data can be transferred via Internet to a remote receiving center. Objectives: The aim of this study was to perform biological testing of the spirometry component in subjects with normal and pathological pulmonary function. Methods: A group of 45 patients (mean age 43.3 years, 30 males) was tested on both the Diagnosa and the standard Jaeger Masterlab spirometer according to the guidelines of the American Thoracic Society. Three subgroups of 15 subjects each (normal spirometry, obstructive and restrictive airflow limitation) were selected. Results: All measurements performed with the Diagnosa (FVC, FIVC, FEV1, PEF, FEF25, FEF50, FEF75) correlated closely (r = 0.92–0.99) with those performed with the Jaeger spirometer and showed good limits of agreement (the largest difference between the two devices being 0.2 liter for FEV1). Analysis of the 3 subgroups showed no difference for any parameters compared to the overall group. Electronic transfer of all data was successful. Conclusions: The Diagnosa spirometer is comparable to a standard laboratory spirometer and can be used reliably for telemedicine purposes.

Capillary refilling time in newborns--optimal pressing time, sites of testing and normal values.

Aspects of capillary refilling time (CRT) in newborns, such as pressing time, sites of testing, normal values and difference between observers were assessed. CRT was measured in 280 term newborns, divided into 7 groups of 40 each, varying pressing time (from 1 to 7 s) was applied. CRT was measured in midpoints of forehead and sternum and plantar surface of heel (defined as head, chest and heel). No statistically significant difference was found between 3 and 7 s pressing time groups. The data points of the CRT of the head and chest approached normality, whilst those of the heel were widely scattered. Normal CRT in newborns is <3 s. No significant difference between two observers in head and chest CRT values was found.

Thrombocytopoenia as marker for HIV exposure in the neonate.

Thrombocytopoenia is a well-described marker of human immunedeficiency virus type 1 (HIV) infection of children. After documenting thrombocytopoenia in a HIV-exposed neonate, who was subsequently shown not to be infected, we evaluated thrombocytopoenia (platelets < 150 x 10(9)/l) as a marker for HIV exposure in newborns. This is, to our knowledge, the first study of thrombocytopoenia in HIV-exposed neonates. A retrospective hospital-based descriptive study was performed over an 18-month period (July 1997-December 1998). Patients were recruited either through identification of known HIV-positive mothers or neonates with thrombocytopoenia who were then screened for HIV exposure. For eligibility, neonates with either HIV antibodies or direct evidence of infection (p24 antigenaemia or HIV RNA detected by polymerase chain reaction after 1 month of age) were included. Thirty-four HIV-exposed (HIV-ELISA positive) neonates were identified, of whom 16 (47 per cent) had thrombocytopenia. In 12 (35 per cent), no underlying cause other than HIV was identified. Nine thrombocytopoenic babies were infected and seven uninfected. Unexplained thrombocytopoenia, while an imperfect marker, should alert the physician to the possibility of HIV exposure. It does not necessarily imply HIV infection. A prospective study is recommended to evaluate further the sensitivity and specificity of this marker.

Chest radiographs of neonates with respiratory failure caused by congenital syphilis

Congenital syphilis still occurs in newborn babies and the prevalence has increased in recent years, especially in developing countries. This has led to an increase in the number of babies with congenital syphilis requiring intensive care for respiratory failure. The early recognition of this disease could lead to the institution of timely and appropriate treatment. In this study the radiological picture of syphilitic pneumonitis is described in 20 neonates admitted to our neonatal intensive care unit requiring ventilation for respiratory failure. The radiological picture of the babies with syphilis was compared to 20 babies with other causes of respiratory distress. The radiological picture in 17 babies demonstrated a coarse nodular pattern in addition to band-like opacities radiating from the hilar regions. The nodular opacities became confluent on follow-up radiographs. In 13 cases, the proximal humeri showed changes typical of congenital syphilis. Two of the three babies with syphilis who did not have the typical chest radiological picture had bony involvement visible on the chest radiograph. Both the sensitivity and specificity of radiographic diagnosis were 75% with a positive and negative predictive value of 75%. The diagnosis of congenital syphilitic pneumonitis can therefore be suspected on chest radiographs and should be included in the differential diagnosis of any baby who presents with an interstitial pattern on chest radiography.

Early surfactant therapy and nasal continuous positive airways pressure for mild respiratory distress syndrome - a pilot study

Objectives To determine if the administration of Curosurf® 100 mg/kg within 24 hours after birth, to infants with respiratory distress syndrome (RDS) receiving nasal continuous positive airways pressure (NCPAP) and inspired oxygen (FiO2) 0.3–0.4, decreased the need for mechanical ventilation (MV) during the first week of life when compared to infants in whom the required FiO2 was allowed to rise above 0.4 before Curosurf® was administered. Design and subjects Twenty-seven preterm infants were randomised into either a low- or a high-threshold group. The low-threshold group received Curosurf® immediately and the high-threshold group received Curosurf® if their FiO2 rose above 0.4. Infants who received surfactant were returned to NCPAP if respiratory effort was adequate. Setting The Neonatal Intensive Care Unit, Groote Schuur Hospital, Cape Town. Results The mean gestational age for the entire cohort was 31  2 weeks. There were no significant differences between the groups with respect to the need for MV in the first week of life. However, the duration of any form of assisted ventilation (NCPAP and MV) was significantly less in the low-threshold group (p= 0.042). The low-threshold group had a lower mean PaCO2 at 24 hours (p = 0.015). Conclusions The administration of 100 mg/kg Curosurf® to preterm infants with RDS requiring NCAP at a threshold FiO2 0.3–0.4, improved alveolar ventilation and reduced the duration of any form of assisted ventilation, compared to waiting until the FiO2 was above 0.4. There was no significant reduction in the need for MV.

Predictors of survival in infants with congenital diaphragmatic hernia - systemic oxygenation status versus dynamic compliance of the respiratory system

Objective . To compare whether early measurement of blood gases and/or dynamic compliance of the respiratory system (CRS dyn ) predicts outcome in high-risk infants with unilateral congenital diaphragmatic hernia (CDH). Patients and methods. A retrospective study was performed at Tygerberg Children’s Hospital between January 1992 and August 2001. High-risk infants with unilateral CDH, who presented with respiratory distress within 6 hours of birth, were included. Patients with other lethal congenital abnormalities were excluded. The first arterial blood gas value after endotracheal intubation was documented and the arterial-alveolar oxygen tension (a:A) ratio was calculated. CRS dyn was measured within 24 hours of birth. The ability of these measurements to predict outcome (survival or death during the newborn period) was determined. Results . Seventeen of 40 infants with CDH were categorised as high risk and included in the study. Eight of them (47%) survived the neonatal period. The best single predictors of outcome were, in order, partial pressure of oxygen in arterial blood (PaO 2 ), a:A ratio and dynamic compliance of the respiratory system standardised for body weight (CRS dyn /kg). The specificity and sensitivity at a PaO 2 cut-off of 19.3 kPa were 7/8 (95% confidence interval (CI): 0.473 - 0.997) and 9/9 (95% CI: 0.634 - 1.000) respectively. Results for a:A ratio were cut-off 0.321, specificity 6/8 (95% CI: 0.349 - 0.968), and sensitivity 9/9 (95% CI: 0.634 - 1.000). Results for CRS dyn /kg were cut-off 0.259, specificity 6/8 (95% CI: 0.349 - 0.968), and sensitivity 9/9 (95% CI: 0.634 - 1.000). A linear discriminant function based on the 3 best single predictors was found to be no more effective than the first PaO 2 . Conclusions . Early oxygenation status predicts outcome better than the CRS dyn /kg in infants with unilateral CDH. However, both measurements predict outcome with high accuracy.