9

Standards of care for the babies

9.1

Introduction

This chapter relates to standards of care for the babies of women with pre-gestational diabetes. It is important to note that assessment of clinical care in this project had, of necessity, to be based on documentation in the medical records. This meant that some standards could be evaluated in part only. This is noted in the text where relevant.

9.2

Facilities at delivery

Concurrent with this cohort project, CEMACH also undertook a survey of the maternity services of organisations expected to be providing maternity care for women with diabetes in England, Wales and Northern Ireland.¹ The hospital of delivery was linked to the data from this organisation survey to assess the level of neonatal care available.¹ Of the 3451 live births, 9.4% (325/3451) could not be assessed because there was no organisation survey response for the unit of delivery. Ninety-five percent (2983/3126) of the remaining babies were born in a unit which had facilities to provide neonatal care above special care, with at least some form of high-dependency and short-term intensive care.

9.3

Admission to a neonatal unit and subsequent mother/baby separation

The admission pattern for infants of mothers with diabetes is detailed in Chapter 8. Of the 3451 live births for which information was available, 1945 (56.4%) were admitted to a neonatal unit for intensive, high-dependency or special care. Thirty-five percent (1216/3451) of all live births were admitted for special care only.

Term infants (delivered at 37 completed weeks of gestation and over) are, in general, unlikely to need care in a neonatal unit. In the term baby population, the admission rate in the UK is generally below 10%.² When term babies or even babies with mild prematurity (that is, those delivered at 35–36 completed weeks of gestation) need admission for special care, some UK hospitals provide alternative models of care, such as mother and baby rooming-in facilities called transitional care units.^3,4

In order to explore the pattern of admission/separation of these babies, we stratified admissions by gestation at delivery of less than 35 completed weeks, 35–36 completed weeks and 37 completed weeks and over. The types of neonatal care for which the baby was managed separately from the mother (special, high-dependency or intensive care) were also categorised. The results for babies delivering at or after 35 completed weeks of gestation is shown in Table 9.1. A high proportion, 32.6% (723/2216) of term infants of mothers with diabetes was admitted for special care. Median stay/separation time for these term infants was 2 days, (interquartile range 1–4). Forty-four percent of infants with mild prematurity (35–36 completed weeks of gestation) were also admitted for special care. The median stay/separation for these infants was 4 days (interquartile range 2–7).

The reasons for admission to a neonatal unit for special care documented in the data collection tool in the term population of infants of mothers with diabetes were categorised (see Chapter 1 for methodology) (Table 9.2). A higher proportion of term babies born to mothers with type 1 diabetes was admitted to a neonatal unit compared with those of mothers with type 2 diabetes (rate ratio 1.18; 95% CI 1.05–1.31; P = 0.003) (see Chapter 8). Nevertheless, the reasons for special care admissions were the same for term babies of mothers with type 1 and type 2 diabetes.

Nearly one-third of term infant admissions (31.1%; (225/723) (group III) were unlikely to be avoidable (hypoglycaemia needing treatment, respiratory symptoms, cyanotic episodes, suspected or confirmed sepsis, feeding difficulties, other medical conditions and ill mother/adoption process).

The results suggest that almost two-thirds of the admissions could have been avoided or potentially avoided. Two main categories emerged:

• Routine admission (group I): one-quarter of admissions occurred for babies with no apparent adverse clinical condition. Reasons provided were: (a) because they were categorised by the hospital staff as “infants of diabetic mothers”; (b) because there was a hospital policy to admit them, regardless of their clinical condition or (c) because of observation/monitoring alone (25.6%; 185/723). These babies may have potentially been managed on a postnatal ward with adequate clinical support.
• Forty-one percent (300/723) of admissions to a neonatal unit for special care (group II) occurred for babies with minor clinical conditions such as isolated hypoglycaemia, cold or jaundiced hypoglycaemia. These babies may have potentially been managed with alternative strategies to routine admissions such as transitional care facilities.^3,4

Overall, these results must be interpreted with some caution since the categorisation was made from the ‘reason for admission’ free text entered by local data collectors into the cohort pro forma. The results from the on-going diabetes enquiry process where panels have direct access to the medical records may help ascertain further these descriptive findings.

9.4

Infant feeding

9.4.1

Timing of first feed

The median time to first feed was 60 minutes, interquartile range 41–104.

Table 9.3 shows 40.1% of all infants were fed within 1 hour and 79.5% by 4 hours. Looking specifically at the population of term infants (37 completed weeks of gestation and over) who should be fed early unless a specific clinical condition requires that the first feed is delayed, eight out of ten babies were fed within the first 4 hours, as specified in the standard.

9.4.2

Breastfeeding

Breast milk appears to promote ketogenesis.⁵ It should be therefore be the food of choice for babies of mothers with diabetes who are at risk of hypoketonaemic hypoglycaemia.⁶ Exclusive breastfeeding was the choice at birth for 53% (1762/3342) of all women in this cohort (Table 9.4). The proportion of women intending to breastfeed was similar for mothers of both preterm and term babies (Table 9.4) and was less than the most recently published UK general population prevalence of breastfeeding of 69%.⁷

At 28 days after birth, the proportion of exclusively breastfed babies was 23.8%, half the proportion who had intended to breastfeed at delivery (Table 9.5). When babies who were both breast and bottle fed were identified, the proportion still having breast milk at 28 days after birth was 40.3%, a 13% drop from breastfeeding intent at the time of birth. This was comparable to the prevalence of breastfeeding at 6 weeks of 42% in UK.⁷ The proportion of preterm babies still exclusively breastfed at 1 month of age was lower (18.5%) than for term babies (26.7%).

9.4.3

Management of feeding

The main reason for giving term infants of mothers with diabetes supplemental milk or glucose was a history of low blood glucose level alone (36.7%) (Table 9.6). Nine percent of term babies had this treatment because of routine local practice and this may affect normal glucose regulation in healthy term babies.⁸ Accepted best practice for intervention in normal term infants comprises the following:

• persistent hypoglycaemia
• persistent hypoglycaemia after a feed
• clinical signs of hypoglycaemia
• both low blood glucose and clinical signs of hypoglycaemia.⁹

However, the results must be interpreted with caution because of the large number of “not known” responses (Table 9.6).

9.5

Blood glucose testing

9.5.1

Early blood glucose testing

Infants of mothers with diabetes display transient hyperinsulinism but, provided that hypoglycaemia is treated appropriately, most studies have found that their neurodevelopmental outcome was similar to that of babies born to women without diabetes.⁶ These infants therefore need reliable blood glucose testing.

Median time to first blood glucose measurement was 60 minutes (interquartile range 30–120); 83.2 % of all infants of mothers with diabetes had a blood glucose test within the first 6 hours of life (Table 9.7). This is mainly within standards and accepted best practice.⁸ Nevertheless, a median time to first blood glucose testing of 1 hour may also suggest that testing was often too early. Testing too early may simply uncover the physiological fall in blood glucose after birth, leading to unnecessary intervention.

9.5.2

Blood glucose testing method

Glucose reagent strips may not be reliable^8,10 and are now regarded as contraindicated in neonates.¹¹ At least one reliable laboratory value should be obtained when considering the diagnosis of hypoglycaemia.⁸ The suitability for the detection of neonatal hypoglycaemia of portable glucose photometer such as HaemoCue (HaemoCue®, Angelholm, Sweden) is not universally accepted;^12–14 however, if used as screen, a suspect/abnormal result value should at least be followed by laboratory confirmation. More accurate laboratory or ward-based glucose electrode measurements are therefore preferable among babies at risk.⁶ Reagent strips were used in one-third of babies. Only 29.3% (362/1253) of preterm infants and 25.0% (555/2216) of term babies were monitored using these optimal testing methods (Table 9.8).^8,10 These results must also be interpreted with caution because of the number of missing values and of the reported difficulties in categorising the blood glucose testing method or combined methods (such as HaemoCue and laboratory) used from the medical records.

9.6

Conclusions on neonatal standards for infants of mothers with diabetes

Some neonatal standards were met:

• The vast majority (95%) of the babies were born in a maternity unit with facilities and staff for neonatal resuscitation.
• Most term (83%) babies were fed shortly after birth and within 4 hours of birth.
• Most babies (83%) had a blood glucose measurement within 6 hours after birth.

Some aspects of clinical care need further improvement:

• Often, babies may have had their first glucose measurement too soon (44% of term babies were tested within the first hour). This may have occurred during the physiological fall in blood glucose after birth and may have led to unnecessary intervention.
• Some babies (9%) were given supplemental feed or glucose because of local routine practice only, possibly compromising the establishment of breastfeeding.
• Optimal blood glucose testing method was used in less than one-third of cases.
• One-third of term babies were admitted to a neonatal unit for special care. The results suggest that many (67%) admissions were possibly avoidable. Alternative strategies to routine neonatal unit admission for babies of mothers with diabetes could be postnatal wards with adequate clinical support, or transitional-care nurseries where the baby is nursed alongside mother.
• Fifty-three percent of women intended to breastfeed. This compares with an initial breastfeeding rate of 69% in the general population.

References

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