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.

Cyclic nucleotide-dependent relaxation in human umbilical vessels.

Umbilical vessels have a low sensitivity to dilate, and this property is speculated to have physiological implications. We aimed to investigate the different relaxing responses of human umbilical arteries (HUAs) and veins (HUVs) to agonists acting through the cAMP and cGMP pathways. Vascular rings were suspended in organ baths for isometric force measurement. Following precontraction with the thromboxane prostanoid (TP) receptor agonist U44069, concentration-response curves to the nitric oxide (NO) donor sodium nitroprusside (SNP), the soluble guanylate cyclase (sGC) stimulator BAY 41-2272, the adenylate cyclase (AC) activator forskolin, the ß-adrenergic receptor agonists isoproterenol (ADRB1), salmeterol (ADRB2), and BRL37344 (ADRB3), and the phosphodiesterase (PDE) inhibitors milrinone (PDE3), rolipram (PDE4), and sildenafil (PDE5) were performed. None of the tested drugs induced a relaxation higher than 30% of the U44069-induced tone. Rings from HUAs and HUVs showed a similar relaxation to forskolin, SNP, PDE inhibitors, and ADRB agonists. BAY 41-2272 was significantly more efficient in relaxing veins than arteries. ADRB agonists evoked weak relaxations (< 20%), which were impaired in endothelium-removed vessels or in the presence of the NO synthase inhibitor L-NAME, sGC inhibitor ODQ. PKA and PKG inhibitors impaired ADBR1-mediated relaxation but did not affect ADRB2-mediated relaxation. ADRB3-mediated relaxation was impaired by PKG inhibition in HUAs and by PKA inhibition in HUVs. Although HUA and HUV rings were relaxed by BRL37344, immunohistochemistry and RT-qPCR analysis showed that, compared to ADRB1 and ADRB2, ADRB3 receptors are weakly or not expressed in umbilical vessels. In conclusion, our study confirmed the low relaxing capacity of HUAs and HUVs from term infants. ADRB-induced relaxation is partially mediated by endothelium-derived NO pathway in human umbilical vessels.

EDIN Scale Implemented by Gestational Age for Pain Assessment in Preterms: A Prospective Study.

Background. Chronic neonatal pain can lead to long-term adverse effects on the immature brain. EDIN scale for prolonged pain might not be fully suitable for premature infants. We aimed to test a modified EDIN scale, adding postmenstrual age (PMA) as a sixth item (EDIN6). Methods. In a two-phase prospective study, pain was assessed in all neonates admitted in our NICU. In T1 EDIN was applied; in T2 EDIN6 with additional scores of 2, 1, and 0, respectively, for 25-32, 33-37, and >37 weeks PCA was tested. Scores > 6 suggested pain. The nursing staff was given a questionnaire to evaluate EDIN and EDIN6. Results. A total of 15960 pain assessments were recorded (8693 in T1; 7267 in T2). With EDIN6, cumulative detection of pain almost tripled (117/7267 versus 52/8693, p = 0.001). Main differences were found among less mature categories (50/1472 versus 17/1734, p = 0.001 in PCA 25-32; 26/2606 versus 10/4335, p = 0.001 in PMA 33-37; 41/3189 versus 25/2624, p = 0.26 in PMA > 37). Adequacy of pain assessment in lower PMA was judged "medium-high" in 13,4% of nurses in T1 and 71,4% in T2. Conclusions. EDIN6 may allow improved evaluation of pain in preterm infants.