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Terrestrial locomotion requires coordinated bilateral activation of limb muscles, with left-right alternation in walking or running, and synchronous activation in hopping or skipping. The neural mechanisms involved in interlimb coordination at birth are well known in different mammalian species, but less so in humans. Here, 46 neonates (of either sex) performed bilateral and unilateral stepping with one leg blocked in different positions. By recording EMG activities of lower-limb muscles, we observed episodes of left-right alternating or synchronous coordination. In most cases, the frequency of EMG oscillations during sequences of consecutive steps was approximately similar between the two sides, but in some cases it was considerably different, with episodes of 2:1 interlimb coordination and episodes of activity deletions on the blocked side. Hip position of the blocked limb significantly affected ipsilateral, but not contralateral, muscle activities. Thus, hip extension backward engaged hip flexor muscle, and hip flexion engaged hip extensors. Moreover, the sudden release of the blocked limb in the posterior position elicited the immediate initiation of the swing phase of the limb, with hip flexion and a burst of an ankle flexor muscle. Extensor muscles showed load responses at midstance. The variable interlimb coordination and its incomplete sensory modulation suggest that the neonatal locomotor networks do not operate in the same manner as in mature locomotion, also because of the limited cortical control at birth. These neonatal mechanisms share many properties with spinal mammalian preparations (i.e., independent pattern generators for each limb, and for flexor and extensor muscles, load, and hip position feedback). SIGNIFICANCE STATEMENT Bilateral coupling and reciprocal activation of flexor and extensor burst generators represent the fundamental mechanisms used by mammalian limbed locomotion. Considerable progress has been made in deciphering the early development of the spinal networks and left-right coordination in different mammals, but less is known about human newborns. We compared bilateral and unilateral stepping in human neonates, where cortical control is still underdeveloped. We found neonatal mechanisms that share many properties with spinal mammalian preparations (i.e., independent pattern generators for each limb, the independent generators for flexor and extensor muscles, load, and hip-position feedback. The variable interlimb coordination and its incomplete sensory modulation suggest that the human neonatal locomotor networks do not operate in the same manner as in mature locomotion., (Copyright © 2022 the authors.)

Background: Near-infrared spectroscopy (NIRS) is a noninvasive technique for monitoring tissue oxygenation and perfusion. The aim of this study was to evaluate cerebral and splanchnic NIRS changes in CDH operated infants enrolled into the VICI trial and therefore randomized for ventilatory modalities., Materials and Methods: CDH newborns enrolled into the VICI trial (Netherlands Trial Register, NTR 1310) were randomized at birth for high-frequency oscillatory ventilation (HFOV) or conventional mechanical ventilation (CMV) according to the trial. Cerebral oxygenation (rSO2C) and splanchnic oxygenation (rSO2S) were obtained by NIRS (INVOS 5100; Somanetics, Troy, MI) before and after surgery. Variations in rSO2C and rSO2S were evaluated. Mann-Whitney test and one-way ANOVA were used as appropriate. p<0.05 was considered significant., Results: Thirteen VICI trial patients underwent surgical repair between March 2011 and December 2012, and were enrolled in the study. Seven patients were assigned to HFOV and six to CMV group respectively. During surgery, a significant reduction in rSO2C (p=0.0001) and rSO2S (p=0.005) were observed. HFOV patients experienced prolonged reduction in rSO2C value (p=0.003) while rSO2S did not vary between HFOV and CMV (p=0.94)., Conclusions: Surgical CDH repair was associated with decrease of cerebral and splanchnic oxygenation, regardless of ventilation. Patients ventilated by HFOV need a longer time interval to recovery normal rSO2C values, than those ventilated by CMV. This may be owing to a different impact of HFOV on patients' hemodynamic status with a higher impairment on total venous return and its negative consequences on cardiac output., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: Near infrared spectroscopy (NIRS) gradually became the gold standard to guide anesthetic conduction during cardiac surgery, and nowadays, it is commonly utilized to monitor cerebral oxygenation during invasive procedures. Preterm babies also benefit from this non-invasive monitoring to prevent neurological sequelae. However, few data are available on NIRS perioperative changes in newborn operated on for major non-cardiac malformations. Aim of the present study is to evaluate the usefulness of NIRS assessment during and after esophageal atresia (EA) correction and its correlation with clinical behavior., Patients and Methods: All patients treated for EA from May 2011 were prospectively enrolled in the study. All infants underwent "open" correction of EA and cerebral and splanchnic NIRS was applied up to 48h after surgery. Body temperature, blood pressure, pH, paSO2, paCO2, and urine output, were recorded during NIRS registration. Mann-Whitney test and 1-way ANOVA (Kruskal-Wallis and Dunn's multiple comparison tests) were used as appropriate., Results: Seventeen patients were enrolled into the study and 13 were available for the analysis. Four patients were excluded because of poor NIRS registration. Cerebral and renal NIRS values significantly decreased at 24h post-operatively (p<0.05). Interestingly, all parameters studied as possible confounders in NIRS remained stable during the study period. Urine output significantly decreased., Conclusion: Our data confirmed that perioperative monitoring of tissue oxygenation during neonatal esophageal surgery is feasible. Cerebral and renal NIRS evaluation, as for cardiac patients, may guide anesthetic conduction and postoperative care. Out data suggest a newly observed hemodynamic reorganization during esophageal surgery involving renal and, probably, splanchnic blood flow redistribution, demonstrated by the observed subsequent significant post-operative transitory decrease in urinary output. Reducing the decrement in cerebral and renal NIRS values may improve, and ideally eliminate, the well-known late sequelae linked to hemodynamic changes during surgery. More studies are needed to better understand the causes of the NIRS described hemodynamic changes and, therefore, correct them., (Copyright © 2014 Elsevier Inc. All rights reserved.)