The effect of delayed umbilical cord clamping on cord blood gas analysis in vaginal and caesarean-delivered term newborns without fetal distress: a prospective observational study.

OBJECTIVE: To determine variations in cord blood gas (CBG) parameters after 3-minute delayed cord clamping (DCC) in vaginal deliveries (VDs) and caesarean deliveries (CDs) at term without fetal distress. DESIGN: Prospective observational study. SETTING: University hospital. SAMPLE: CBG from 97 VDs and 124 CDs without fetal distress. METHODS: Comparison of paired arterial-venous CBG parameters drawn at birth from the unclamped cord and after 3-minutes DCC for VDs and CDs. MAIN OUTCOME MEASURES: Base excess, bicarbonate, haematocrit and haemoglobin from both arterial and venous cord blood, lactate, neonatal outcomes, partial pressure of oxygen (pO2 ), partial pressure of carbon dioxide (pCO2 ), pH, and postpartum haemorrhage. RESULTS: Arterial cord blood pH, bicarbonate ( HCO3- , mmol/l), and base excess (BE, mmol/l) decreased significantly after 3-minute DCC both in VDs (pH = 7.23 versus 7.27; P < 0.001; HCO3-  = 23.3 versus 24.3; P = 0.004; BE = -5.1 versus -2.9; P < 0.001) and CDs (pH = 7.28 versus 7.34; P < 0.001; HCO3-  = 26.2 versus 27.2; P < 0.001; BE = -1.5 versus 0.7; P < 0.001). After 3-minute DCC, pCO2 increased in CDs only (57 versus 51; P < 0.001), whereas lactate increased more in CDs compared with VDs (lactate, +1.1 [0.9, 1.45] versus +0.5 [-0.65, 2.35]; P = 0.01). Postpartum maternal haemorrhage, neonatal maximum bilirubin concentration, and need for phototherapy were similar between the two groups. Newborns born by CD more frequently required postnatal clinical monitoring or admission to a neonatal intensive care unit. CONCLUSIONS: After 3-minute DCC, the acid-base status shifted towards mixed acidosis in CDs and prevalent metabolic acidosis in VDs. CDs were associated with a more pronounced increase in arterial lactate, compared with VDs. TWEETABLE ABSTRACT: By 3-minute DCC, acid-base status shifts towards mixed and metabolic acidosis in caesarean and vaginal delivery, respectively.

Clinical features of a fatal shoulder dystocia: The hypovolemic shock hypothesis.

Shoulder dystocia is a rare but severe obstetric complication associated with an increased risk of brachial plexus palsies, fractures of the clavicle and humerus, hypoxic-ischemic encephalopathy and, rarely, neonatal death. Here we describe a fatal case of shoulder dystocia in a term newborn, although labor was uneventful, fetal heart rate tracing was normal until the delivery of the head and the head-to-body delivery interval (HBDI) occurred within 5 min. Full resuscitation was performed for 35 min without success. Hemoglobin concentration evaluated on the umbilical cord still attached to the placenta was within normal range, while neonatal venous hemoglobin concentration blood gases at 9 min of life showed severe metabolic acidosis and anemia. As previously described by others, our case supports the hypothesis of a hypovolemic shock as the cause of neonatal death, probably due to acute placental retention of fetal blood. The death of the newborn following shoulder dystocia is an event that still presents numerous gaps in knowledge. Further research should focus on.

Magnetic resonance imaging of the hypothalamus-pituitary unit in childrensuspected of hypopituitarism: who, how and when toinvestigate.

The magnetic resonance (MR) identification of pituitary hyperintensity in the posterior part of the sella has been the most striking recent finding contributing to the diagnosis of "idiopathic" and permanent GH deficiency (GHD). Moreover, advancements in DNA technology have shed new light on the study of the genetic causes of hypopituitarism. Abnormalities in two genes, the GH-N encoding the GH and the GHRH receptor (GHRH-R), have been identified, while mutations in five other gene-encoding transcription factors such as Pit-1, Prop-1, Hesx-1, Lhx-3 and Lhx-4 involved in anterior pituitary development, have also been described. MR imaging shows marked differences in pituitary morphology indicating different GHD etiologies and different prognoses. Ectopic posterior pituitary is a specific marker of permanent GHD. These patients do not have Pit-1, Prop-1, or Lhx-3 mutations and should be carefully monitored for evolving pituitary hormone defects, though they do not require GH re-evaluation in adulthood; selected cases may have Hesx-1 or Lhx-4 mutations. MR evidence of normal or small anterior pituitary gland, enlarged empty sella, pituitary hyperplasia and/or intrasellar or suprasellar mass when associated with combined pituitary hormone deficiency call for molecular analysis of Pit-1, Prop-1, Hesx-1, or Lhx-3. Limitation of neck rotation and Chiari-I malformation may suggest Lhx-3 or Lhx-4 mutations (exceedingly rare). In "idiopathic" isolated GHD, evidence of normal anterior or small anterior pituitary size with normal location of posterior pituitary and normal connection between the hypothalamus and pituitary gland is suggestive of "transitory" or false positive GHD; patients with such characteristics should be re-evaluated well before reaching adult height. In selected cases, anterior pituitary height that is 2 SD below age-adjusted normal pituitary height could be suggestive of GHRH-R gene defect; it is worth pointing out that normal pituitary MR together with severe GHD has been observed, though rarely, in subjects with a genetic origin of GHD.