Major Mental Handicap: methods and costs of prevenfion Editors: KATHERINE ELLIOTT (Organizer) and MAEVE O'CONNOR Copyright 01978 Ciba Foundation
Outcome for infants at high risk of major handicap ANN STEWART, DIANE TURCAN, GRACE RAWLINGS, SUSANNA HART and SHEILA GREGORY Departments of Paediatrics and Obstetrics, University College Hospital and Medical School, London
Abstract Perinatal intensive care had been introduced in University College Hospital, London, by 1966. In the succeeding 10 years, 28-day mortality rates fell among infants of birth weight 1500 g or less. Among the survivors, the incidence of major handicap was 10%or less and the mean IQ increased to within the range expected for a normal population. Of the children aged 8 years or more 76% had no handicaps and were attending normal schools; 18% had minor handicaps or problems for which they were receiving extra help in normal schools; and only 6% were attending special schools. Throughout the 10 years of the study, the overall prognosis for these infants of very low birth weight improved significantly. Results among other high-risk groups were equally encouraging. Analysis of variance of the data from the infants who weighed 1500 g or less at birth indicated that perinatal complications, particularly illnesses associated with abnormal neurological signs or acidaemia in the infants around the time of birth, were the principal factors determining the condition of the survivors at follow-up. Thus, it is likely that additional refinements in the management of the perinatal period may result in further improvements in the prognosis of these and other high-risk newborns.
Professors Hobel and Reynolds have discussed the current attitudes and methods used in the management of the perinatal period. At University College Hospital, London, we have been using these techniques for more than 10 years in an attempt to improve the prognosis for high-risk pregnancies and to prevent brain damage among the surviving infants. Before these methods were introduced, workers in other centres had reported very high mortality rates in, for example, infants of very low birth weight and incidences of major handicap of 50% or more among the survivors (Knobloch et al. 1956; Drillien 1958, 1961; Lubchenco et al. 1963; Bacola et al. 1966; MacDonald 1967). Some, notably Drillien (196 l), warned at that time that efforts directed at the improvement in mortality among such infants might lead only to increasing numbers of handicapped survivors entering the community. We have there151
152
A. STEWART ET AL.
fore attempted to follow up all the survivors of the highest-risk infants that we have cared for since 1966. POPULATION
Our study mainly concerned the 589 infants who weighed 1500 g or less at birth and were admitted to our newborn unit. We have also studied 124 surviving infants of birth weight 1501-2500 g; 123 surviving infants of birth weight greater than 1000 g who were treated with mechanical ventilation for hyaline membrane disease; and 30 infants who survived after severe rhesus disease. Professor Hobel and Professor Reynolds have discussed the type of methods used in the perinatal management of such infants. Although much of this regime had been introduced in University College Hospital by 1966, refinements were introduced in the succeeding years. For example, although we were able to mechanically ventilate the children with respiratory failure due to preterm apnoea in 1966, it was not until 1970 that techniques were developed which allowed the mechanical ventilation of infants with severe hyaline membrane disease at pressures low enough to avoid serious damage to the lungs (Reynolds 1971). Likewise, although we were able to maintain a reasonably adequate calorie intake with oral feeding and peripheral intravenous infusions of dextrose solutions in 1966, parenteral nutrition was not introduced until 1971 (Shaw 1973). After they left hospital, the children were assessed regularly in the followup clinic, where clinical and neurological examinations were done and, during the first 18 months, developmental testing (Knobloch et al. 1966). Thereafter, psychological assessments were made at 3.5, 5 and 8 years, including educational and attainment tests, behavioural ratings and tests of motor skills among the older children (Stewart et al. 1977). Hearing and vision were assessed from behavioural responses during the first year of life. Audiograms and refraction under dilatation were carried out between 3.5 and 5 years, depending on the cooperation of the individual children. Throughout the study, the children’s ages were corrected for preterm delivery on all assesments before 5 years of age. RESULTS
Group I: infants of birth weight i 1500 g Mortality.
In the 11 years, 1966-1976,589 infants of birth weight 1500 g or
OUTCOME FOR INFANTS AT HIGH RISK OF MAJOR HANDICAP
153
TABLE 1 Mortality at 28 days according to method of delivery, among 236 of 589 infants admitted to University College Hospital, London, 1966- 1976 500-15OOg
‘Spontaneous’vertex Forceps Breech ? F.A.C.H. Caesarean section 1000 g or less
Vaginal delivery Caesarean section
% Mortality
45 39 52
18 P t0.001
73 36 P 170 pmol/l Recurrent preterm apnoea, onset > 3 days Maternal hypertension Maternal pre-eclampsia Maternal vaginal bleeding Abnormal haemostasis Apgar score at 1 min Apex beat at birth Maternal infertility Prolapse of the cord Duration of ruptured membranes Negative base excess (arterial sample within 2 of birth) Total -
-
h
9.12 10.09 11.04 12.09 12.92 13.70 14.50 15.03 15.49 15.69 15.89 16.13 16.24 16.35 16.47 16.57 16.66 16.69 16.70 16.71 16 71
~
Overall ‘F’ for 22 variables = 2 17, P
Outcome for infants at high risk of major handicap ANN STEWART, DIANE TURCAN, GRACE RAWLINGS, SUSANNA HART and SHEILA GREGORY Departments of Paediatrics and Obstetrics, University College Hospital and Medical School, London
Abstract Perinatal intensive care had been introduced in University College Hospital, London, by 1966. In the succeeding 10 years, 28-day mortality rates fell among infants of birth weight 1500 g or less. Among the survivors, the incidence of major handicap was 10%or less and the mean IQ increased to within the range expected for a normal population. Of the children aged 8 years or more 76% had no handicaps and were attending normal schools; 18% had minor handicaps or problems for which they were receiving extra help in normal schools; and only 6% were attending special schools. Throughout the 10 years of the study, the overall prognosis for these infants of very low birth weight improved significantly. Results among other high-risk groups were equally encouraging. Analysis of variance of the data from the infants who weighed 1500 g or less at birth indicated that perinatal complications, particularly illnesses associated with abnormal neurological signs or acidaemia in the infants around the time of birth, were the principal factors determining the condition of the survivors at follow-up. Thus, it is likely that additional refinements in the management of the perinatal period may result in further improvements in the prognosis of these and other high-risk newborns.
Professors Hobel and Reynolds have discussed the current attitudes and methods used in the management of the perinatal period. At University College Hospital, London, we have been using these techniques for more than 10 years in an attempt to improve the prognosis for high-risk pregnancies and to prevent brain damage among the surviving infants. Before these methods were introduced, workers in other centres had reported very high mortality rates in, for example, infants of very low birth weight and incidences of major handicap of 50% or more among the survivors (Knobloch et al. 1956; Drillien 1958, 1961; Lubchenco et al. 1963; Bacola et al. 1966; MacDonald 1967). Some, notably Drillien (196 l), warned at that time that efforts directed at the improvement in mortality among such infants might lead only to increasing numbers of handicapped survivors entering the community. We have there151
152
A. STEWART ET AL.
fore attempted to follow up all the survivors of the highest-risk infants that we have cared for since 1966. POPULATION
Our study mainly concerned the 589 infants who weighed 1500 g or less at birth and were admitted to our newborn unit. We have also studied 124 surviving infants of birth weight 1501-2500 g; 123 surviving infants of birth weight greater than 1000 g who were treated with mechanical ventilation for hyaline membrane disease; and 30 infants who survived after severe rhesus disease. Professor Hobel and Professor Reynolds have discussed the type of methods used in the perinatal management of such infants. Although much of this regime had been introduced in University College Hospital by 1966, refinements were introduced in the succeeding years. For example, although we were able to mechanically ventilate the children with respiratory failure due to preterm apnoea in 1966, it was not until 1970 that techniques were developed which allowed the mechanical ventilation of infants with severe hyaline membrane disease at pressures low enough to avoid serious damage to the lungs (Reynolds 1971). Likewise, although we were able to maintain a reasonably adequate calorie intake with oral feeding and peripheral intravenous infusions of dextrose solutions in 1966, parenteral nutrition was not introduced until 1971 (Shaw 1973). After they left hospital, the children were assessed regularly in the followup clinic, where clinical and neurological examinations were done and, during the first 18 months, developmental testing (Knobloch et al. 1966). Thereafter, psychological assessments were made at 3.5, 5 and 8 years, including educational and attainment tests, behavioural ratings and tests of motor skills among the older children (Stewart et al. 1977). Hearing and vision were assessed from behavioural responses during the first year of life. Audiograms and refraction under dilatation were carried out between 3.5 and 5 years, depending on the cooperation of the individual children. Throughout the study, the children’s ages were corrected for preterm delivery on all assesments before 5 years of age. RESULTS
Group I: infants of birth weight i 1500 g Mortality.
In the 11 years, 1966-1976,589 infants of birth weight 1500 g or
OUTCOME FOR INFANTS AT HIGH RISK OF MAJOR HANDICAP
153
TABLE 1 Mortality at 28 days according to method of delivery, among 236 of 589 infants admitted to University College Hospital, London, 1966- 1976 500-15OOg
‘Spontaneous’vertex Forceps Breech ? F.A.C.H. Caesarean section 1000 g or less
Vaginal delivery Caesarean section
% Mortality
45 39 52
18 P t0.001
73 36 P 170 pmol/l Recurrent preterm apnoea, onset > 3 days Maternal hypertension Maternal pre-eclampsia Maternal vaginal bleeding Abnormal haemostasis Apgar score at 1 min Apex beat at birth Maternal infertility Prolapse of the cord Duration of ruptured membranes Negative base excess (arterial sample within 2 of birth) Total -
-
h
9.12 10.09 11.04 12.09 12.92 13.70 14.50 15.03 15.49 15.69 15.89 16.13 16.24 16.35 16.47 16.57 16.66 16.69 16.70 16.71 16 71
~
Overall ‘F’ for 22 variables = 2 17, P
