Introduction & Overview
Birth Asphyxia: A Review of the Clinical Problem
Introduction and Overview
The opening presentation was given by Anthony Costello of the Institute of Child Health, and Great Ormond St. Hospital, London,U.K.
Dr. Costello first described the need for a uniform definition of birth asphyxia. This is a problem which has plagued this issue, making it difficult to compare data from various studies and countries. Operationally Dr. Costello has employed the following definition: “Birth asphyxia refers to the impairment of the normal exchange of respiratory gases during the birth process and the ensuing adverse effects on the fetus”. Such a definition would include “fresh stillbirths, infant who does not breathe well by one minute, neonatal encephalopathy, early neonatal death, impairment and disability”. He also provided definitions and illustrations of mild, moderate and severe hypoxic ischemic encephalopathy (“NIE”)”. (Figure 1.1) Also, he referred to the neurodevelopmental consequences of NIE, such as microcephaly, cerebral palsy and cortical blindness.
Dr. Costello described the work of his team in Nepal (reported in Ellis et al BMJ 2000, 320,1229-36). The prevalence of post-asphyxial perinatal mortality and morbidity was compared between Kathmandu and the United Kingdom (Figure 1.2). The total mortality rate was 45/1000 in Kathmandu vs 10/1000 in UK. Furthermore, a large portion of the mortality in Kathmandu was due to stillbirths (85/1000 live births). It was also evident from that study that there were a large number of survivors of birth asphyxia-related neonatal encephalopathy.
Dr. Costello’s group studied the outcome at one year of those diagnosed as “grade 1, 2, or 3” NE (Figure 1.3). They found that almost all with grade 3 were dead by one year; 25% of grade 2 were dead, but approximately 45% were impaired. Of the grade 1 cases, 18% were dead and only about 5% were impaired.
The studies emphasized that the outcome of birth asphyxia is not only death but also impairment. Furthermore it would appear that factors leading to neonatal birth asphyxia are also a cause of stillbirths.
They then studied apparent causes of this form of perinatal mortality and morbidity (Figures 1.4, 1.5). They concluded that there were both antepartum (nutritional status; infections; primiparity; twins; malpresentation; short stature; maternal anemia) and intrapartum factors (induction with syntocin; prolonged rupture of membranes; thick meconium).
Dr. Costello reviewed other reports relating to the incidence of birth asphyxia as a cause of neonatal death: In India (reference) 20%; in Bangladesh (reference) 26% and in Tanzania (reference) 26%. Dr. Costello then cited a recent report by Darmstadt et al (Figure 1.6) which provided a list of evidence–based, cost effective interventions to reduce birth asphyxia.
While it is clear that many of these interventions show high efficacy, in order to have a real impact they should be effective in community settings. Dr. Costello referred to the important studies of Bang (Figure 1.7) in India using trained village women to monitor and treat babies at risk This produced a remarkable reduction of 62% in neonatal mortality.
Dr. Costello then described a study with a team based in rural Nepal in which women’s groups were trained in neonatal care and intervention (Figure 1.8). This was studied as a randomized control trial. The results showed a reduction in NMR from 36.9 to 24.6 and in maternal mortality from 341/100,000 to 69/100,000 (Figure 1.9)
Dr. Costello also estimated the cost of implementing such a program and determined the cost would be $ 0.75 per capita. Possibly the cost will be lower as the programs evolve.
He summarized this important form of health care as “A new PCR method for DNA” which means: “Participation in the Community for Reproductive Health” for “Women who Do Not Attend.”
He discussed training health care workers in neonatal resuscitation and cited several studies in which this had been done (see Perspective on India section of symposium presentations). He then described an on-going trial testing whether bag and mask training improved neonatal care in a community setting in Nepal.
One comment by a traditional birth attendant described the situation before any form of training. She said: “Now we realize that many babies were buried before they died. In the past, we could not differentiate between the baby who had died and who could not breathe. We didn’t know how to deal with this situation. Now we are confident we will be able to save many lives.”