Threshold of metabolic acidosis associated with newborn cerebral palsy: medical legal implications

Obstetricians and gynecologists belong to 1 of the medical specialties with the highest rate of litigation claims. Among birth injury cases, those cases with cerebral palsy outcomes account for litigation settlements or judgments often in the millions of dollars. In cases of potential perinatal asphyxia, a threshold level of metabolic acidosis (base deficit ≥12 mmol/L) is necessary to attribute neonatal encephalopathy to an intrapartum hypoxic event. With increasing duration or severity of a hypoxic stress resulting in metabolic acidosis, newborn infant umbilical artery base deficit increases. It may be alleged that, as base deficit levels increase beyond 12 mmol/L, there is an increased likelihood and severity of cerebral palsy. As a corollary, it may be claimed that an earlier delivery (by minutes) would reduce the base deficit and prevent or reduce the severity of cerebral palsy. This issue is of relevance to obstetricians as defendants, because retrospective "expert" analysis of cases may suggest that optimal management decisions would have resulted in an earlier delivery. In addressing the association of metabolic acidosis and cerebral palsy, base deficit should be measured as the extracellular component (base deficit_{extracellular fluid}) rather than the commonly used base deficit_blood. Studies suggest that, beyond the base deficit threshold of 12 mmol/L, the incidence and severity of cerebral palsy does not significantly increase (until ≥20 mmol/L), although the risk of neonatal death rises markedly. Thus, among most infants with hypoxia-associated neonatal encephalopathy, the occurrence of cerebral palsy is unlikely to be impacted by delivery time variation of few minutes, and this argument should not serve as the basis for medical legal claims.

Third trimester insulin levels are not correlated with fetal macrosomia or delivery complications

OBJECTIVE

To examine the relationship of glucose and insulin levels during the 1-hour gestational diabetes screening test to determine their relation to gestational diabetes mellitus (GDM) and possible resulting pregnancy complications.

STUDY DESIGN

This is a prospective observational study of the delivery records of 784 patients who obtained third trimester screening for both glucose and insulin levels during routine 1-hour 50 g oral glucose load.

RESULTS

Insulin levels were positively correlated with glucose levels (p < 0.001). GDM was diagnosed in 17 patients (2.2%). Mean birth weight was not significantly different with glucose levels < 130 pmol/L, 130-140 pmol/L, or > 140 pmol/L (3,282 g, 3,409 g, and 3,310 g, respectively, p = 0.13), nor were 5-minute Apgar scores (p = 0.66). No difference in mean fetal birth weight was found in insulin ranges < 30 pmol/L, 30-60 pmol/L, and > 60 pmol/L (3,330 g, 3,306 g, and 3,276 g, respectively, p = 0.56). Moreover, no significant differences in 5-minute Apgar scores were observed between those groups (p = 0.05). Women who underwent cesarean section (n = 230) had significantly higher glucose and insulin levels than did those who had vaginal deliveries (n = 554) (p = 0.01 and p = 0.003, respectively).

CONCLUSION

Our data indicates that neither insulin nor glucose levels are predictive of fetal macrosomia, low Apgar scores, or birth injuries.

[The role of S100B-protein in neonatology, pediatric intensive care, and pediatrics]

During the last years neuromonitoring with various biochemical markers such as S100B protein has been introduced into the clinical settings of neonatal and pediatric intensive care. Several investigations have been undertaken to correlate S100B protein concentrations to the diagnosis and prognosis of neonates and children with severe cerebral disorders. This articles gives a review on the current knowledge, indications and limitations on the use of S100B protein after non-traumatic and traumatic brain injury in neonates and children.

[Changes of the thyroid hormone status in children with cerebral palsy and other neurological pathology]

Content of thyroid hormones (T3 and T4) and thyrotropin (TTG) hormone in blood plasma has been studied in 142 children with neurological pathology (cerebral palsy, perinatal CNS lesion). In most cases, there was a significant increase of T3 and T4 and reduction of TTG as compared to control group of healthy children. The changes of thyroid hormones content depended on the patient's age and severity of a pathological condition. A mother pregnancy course impacted on the hormones level. The content of T3 and T4 in blood plasma was higher in case of cystitis in mother's anamnesis or a persistent threat of preterm delivery. In patients, a TTG reduction correlated with mental retardation. In those with marked dysplasia of osseous tissue (osteoclast, osteopathy), the TTG content was higher comparing to patients without such malformations.

[A trial of the use of the multivitamin Multitabs in the combined treatment of patients with a perinatal brain lesion]

Pediatric patients in early childhood presenting with perinatal affection of the nervous system benefit much from incorporation into their combined treatment of multivitamins "Multitabs", as evidenced by improvement in their general health, as well as in the red blood parameters and immunity status. Thus, use of the above multivitamins for children presenting with perinatal cerebral pathology is considered liable to be of benefit making for optimization of the process of treatment.

Nucleated red blood cells: an update on the marker for fetal asphyxia

OBJECTIVE

Our goal was to update our experience with nucleated red blood cells as a marker for fetal asphyxia and to determine whether a relationship exists between the presence of nucleated red blood cells and long-term neurologic impairment.

STUDY DESIGN

Nucleated red blood cell data from 153 singleton term neurologically impaired neonates were compared with cord blood nucleated red blood cells of 83 term nonasphyxiated newborns. Newborns with anemia, intrauterine growth restriction, and maternal diabetes were excluded. The group of neurologically impaired neonates was separated into the following subgroups: group I, persistent nonreactive fetal heart rate pattern from admission to delivery (n = 69); group II, reactive fetal heart rate on admission followed by tachycardia with decelerations and absent variability (n = 47); group III, reactive fetal heart rate on admission followed by an acute prolonged deceleration (n = 37). The first and highest nucleated red blood cell value and the time of nucleated red blood cell disappearance were assessed.

RESULTS

The mean number of initial nucleated red blood cells was significantly higher in the group of neurologically impaired neonates (30.3 +/- 77.5, range 0 to 732 per 100 white blood cells) than in the control group (3.4 +/- 3.0, range 0 to 12 per 100 white blood cells) (p < 0.000001). When the group of neurologically impaired neonates was separated on the basis of timing of the neurologic impairment, distinct nucleated red blood cell patterns were observed. Significant differences were obtained between each of the three groups of neurologically impaired neonates and the normal group, with respect to initial nucleated red blood cells (group I, 48.6 +/- 106.9; group II, 11.4 +/- 9.8; group III, 12.6 +/- 13.4; p < or = 0.000002). Maximum nucleated red blood cell values were higher in group I (mean 51.5 +/- 108.9) than in groups II and III combined (mean 12.7 +/- 11.9) (p = 0.0005). Group I also had a longer clearance time (119 +/- 123 hours) than groups II and III combined (mean 59 +/- 64 hours) (p < 0.001).

CONCLUSION

Our ongoing study indicates that nucleated red blood cells identify the presence of fetal asphyxia. When fetal asphyxia is present, distinct nucleated red blood cell patterns are observed that relate to the timing of fetal injury. In general, intrapartum injuries are associated with lower nucleated red blood cell values. Thus our data continue to support the concept that nucleated red blood cell levels may assist in determining the timing of fetal neurologic injury.

Maternal and neonatal C-reactive protein after interventions during delivery

To evaluate the effects of interventions during delivery on the maternal and neonatal C-reactive protein (CRP) we prospectively measured CRP by immunoturbidometry in 238 mother-infant pairs (179 normal vaginal deliveries, 36 cesarean sections and 23 vacuum extractions) at 24 and 72 hours after delivery. We additionally measured CRP in peripheral maternal and neonatal blood immediately after birth in 29 uncomplicated vaginal deliveries. CRP values in the mothers and their offspring were low at birth, but rose significantly during the first day after vaginal delivery. Cesarean section induced a pronounced elevation of maternal CRP, but had no effect on neonatal values. Delivery by vacuum extraction produced a transient elevation of both maternal and neonatal CRP at 24 hours after birth. Neonatal CRP values were not associated with presence or size of superficial birth tissue trauma evaluated simultaneously with blood sampling. Increased CRP release in mothers and their infants after interventions during delivery may be associated with varying degrees of tissue trauma and can complicate assessment of the presence of infection.

Serum macro creatine kinase type 2 in asphyxiated newborn infants

The presence of macro creatine kinase type 2 (MCK2) activity was noted in the serum of seven out of 32 newborn infants with perinatal asphyxia or birth trauma. MCK2 isoenzyme, when present, represented 15-35% of the total creatine kinase (CK) activity. The clinical and biochemical features of the seven MCK2-positive and 25 MCK2-negative newborns were compared. The infants with MCK2 activity were all males and clinically appeared to be more severely injured, requiring longer hospitalization. Total CK activity was similar in the two groups and CK-MB and CK-BB isoenzyme fractions were present in a similar proportion of infants in both groups. Two infants in each group had long-term neurological disorders. Although the presence of MCK2 has been noted in adult patients with end-stage metastatic solid tumors, the presence of this isoenzyme has not previously been reported in newborn infants.

[Plasma cortisol levels in the newborn infants with hypoxic and traumatic injuries of the spinal cord]

Adrenal glucocorticoid function was studied in 56 newborns with natal injuries of the cervical section of the spine and the contribution of the hypoxic factor to such injuries defined. The babies were examined by the cliniconeurologic and electron-neuromyographic methods in order to specify the level of the injury. Blood serum and umbilical blood hydrocortisone levels were radioimmunoassayed immediately at birth and on days 5-7 of life. Spinal injury at the C1-C4 level was associated with low hydrocortisone levels, that may be regarded as an additional criterion for the differentiation of the level of injury in traumas of the cervical portion of the spine in the newborns.

Calcitonin and parathyroid hormone in newborn infants with fracture of the clavicle

Determinations of serum calcium (Ca), phosphorus (P), calcitonin (CT), and parathyroid hormone (PTH) were carried out in 36 full-term newborn infants with fracture of the clavicle (CF) and in 46 normal neonates (N). At the 6th hour of life the CF neonates demonstrated lower serum Ca and higher serum CT in comparison with normal infants. In the hours following, no significant differences between the two groups for the Ca levels were found, whereas serum CT remained significantly higher in the CF newborns at the 24th, 48th, and 72nd hour of life. Significant differences between normal and CF infants in the PTH serum levels were detected only at the 48th hour, when PTH was lower in the CF newborns. The results of this investigation indicate that the fracture of the clavicle is a significant and peculiar factor in stimulating CT secretion. Serum Ca level appeared to be controlled by CT rather than auto-regulating the secretion of the hormone.