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Oxygen Supplementation to Stabilize Preterm Infants in the Fetal to Neonatal Transition: No Satisfactory Answer.

Torres-Cuevas I, Cernada M, Nuñez A, Escobar J, Kuligowski J, Chafer-Pericas C, Vento M - Front Pediatr (2016)

Bottom Line: Immediately after birth with the initiation of breathing, the lung expands and oxygen availability to tissue rises by twofold, generating a physiologic oxidative stress.However, both lung anatomy and function and the antioxidant defense system do not mature until late in gestation, and therefore, very preterm infants often need respiratory support and oxygen supplementation in the delivery room to achieve postnatal stabilization.Notably, interventions in the first minutes of life can have long-lasting consequences.

View Article: PubMed Central - PubMed

Affiliation: Neonatal Research Group, Health Research Institute La Fe , Valencia , Spain.

ABSTRACT
Fetal life elapses in a relatively low oxygen environment. Immediately after birth with the initiation of breathing, the lung expands and oxygen availability to tissue rises by twofold, generating a physiologic oxidative stress. However, both lung anatomy and function and the antioxidant defense system do not mature until late in gestation, and therefore, very preterm infants often need respiratory support and oxygen supplementation in the delivery room to achieve postnatal stabilization. Notably, interventions in the first minutes of life can have long-lasting consequences. Recent trials have aimed to assess what initial inspiratory fraction of oxygen and what oxygen targets during this transitional period are best for extremely preterm infants based on the available nomogram. However, oxygen saturation nomogram informs only of term and late preterm infants but not on extremely preterm infants. Therefore, the solution to this conundrum may still have to wait before a satisfactory answer is available.

No MeSH data available.


Related in: MedlinePlus

Acetyl-coA is the merging metabolite derived from basic nutrients. Entering into the inner mitochondrial space acetyl-coA will undergo a metabolic transformation in the tricarboxylic cycle (Kreb’s cycle). During this process, highly energized electrons are liberated and transported by specific electron transporters to the electron transport chain (ETC). Energy is used to extrude protons and thus establish a transmembrane potential (Ψm). In the final step, ATP synthase will again intrude protons in the inner mitochondrial space. The energy provided by Ψm will be employed to synthesize adenosine triphosphate (ATP) from adenosin diphosphate (ADP). Oxygen will be reduced with four electrons and combined with two protons to form water. This process is known as oxidative phosphorylation.
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Figure 1: Acetyl-coA is the merging metabolite derived from basic nutrients. Entering into the inner mitochondrial space acetyl-coA will undergo a metabolic transformation in the tricarboxylic cycle (Kreb’s cycle). During this process, highly energized electrons are liberated and transported by specific electron transporters to the electron transport chain (ETC). Energy is used to extrude protons and thus establish a transmembrane potential (Ψm). In the final step, ATP synthase will again intrude protons in the inner mitochondrial space. The energy provided by Ψm will be employed to synthesize adenosine triphosphate (ATP) from adenosin diphosphate (ADP). Oxygen will be reduced with four electrons and combined with two protons to form water. This process is known as oxidative phosphorylation.

Mentions: Oxygen (O2) is indispensable for the provision of sufficient energy to allow multicellular organisms an adequate growth and development. Nutritional components, such as carbohydrates, fat, and proteins, are converted during digestion in simple molecules, such as glucose, fatty acids, or amino acids. Combustion of these nutritional elements in the mitochondria in the presence of oxygen occurs in a two-step process known as oxidative phosphorylation (Figure 1). The energy balance derived from oxidative phosphorylation is substantially more efficient than in anaerobic metabolism. Hence, while 1 mol of glucose generates a positive balance of 2 mol of adenosine triphosphate (ATP) under anaerobic conditions, in the presence of O2, it will generate 32–36 mol of ATP. Thus, the energy efficiency of aerobic is 16–18 times that of anaerobic metabolism (2).


Oxygen Supplementation to Stabilize Preterm Infants in the Fetal to Neonatal Transition: No Satisfactory Answer.

Torres-Cuevas I, Cernada M, Nuñez A, Escobar J, Kuligowski J, Chafer-Pericas C, Vento M - Front Pediatr (2016)

Acetyl-coA is the merging metabolite derived from basic nutrients. Entering into the inner mitochondrial space acetyl-coA will undergo a metabolic transformation in the tricarboxylic cycle (Kreb’s cycle). During this process, highly energized electrons are liberated and transported by specific electron transporters to the electron transport chain (ETC). Energy is used to extrude protons and thus establish a transmembrane potential (Ψm). In the final step, ATP synthase will again intrude protons in the inner mitochondrial space. The energy provided by Ψm will be employed to synthesize adenosine triphosphate (ATP) from adenosin diphosphate (ADP). Oxygen will be reduced with four electrons and combined with two protons to form water. This process is known as oxidative phosphorylation.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4835680&req=5

Figure 1: Acetyl-coA is the merging metabolite derived from basic nutrients. Entering into the inner mitochondrial space acetyl-coA will undergo a metabolic transformation in the tricarboxylic cycle (Kreb’s cycle). During this process, highly energized electrons are liberated and transported by specific electron transporters to the electron transport chain (ETC). Energy is used to extrude protons and thus establish a transmembrane potential (Ψm). In the final step, ATP synthase will again intrude protons in the inner mitochondrial space. The energy provided by Ψm will be employed to synthesize adenosine triphosphate (ATP) from adenosin diphosphate (ADP). Oxygen will be reduced with four electrons and combined with two protons to form water. This process is known as oxidative phosphorylation.
Mentions: Oxygen (O2) is indispensable for the provision of sufficient energy to allow multicellular organisms an adequate growth and development. Nutritional components, such as carbohydrates, fat, and proteins, are converted during digestion in simple molecules, such as glucose, fatty acids, or amino acids. Combustion of these nutritional elements in the mitochondria in the presence of oxygen occurs in a two-step process known as oxidative phosphorylation (Figure 1). The energy balance derived from oxidative phosphorylation is substantially more efficient than in anaerobic metabolism. Hence, while 1 mol of glucose generates a positive balance of 2 mol of adenosine triphosphate (ATP) under anaerobic conditions, in the presence of O2, it will generate 32–36 mol of ATP. Thus, the energy efficiency of aerobic is 16–18 times that of anaerobic metabolism (2).

Bottom Line: Immediately after birth with the initiation of breathing, the lung expands and oxygen availability to tissue rises by twofold, generating a physiologic oxidative stress.However, both lung anatomy and function and the antioxidant defense system do not mature until late in gestation, and therefore, very preterm infants often need respiratory support and oxygen supplementation in the delivery room to achieve postnatal stabilization.Notably, interventions in the first minutes of life can have long-lasting consequences.

View Article: PubMed Central - PubMed

Affiliation: Neonatal Research Group, Health Research Institute La Fe , Valencia , Spain.

ABSTRACT
Fetal life elapses in a relatively low oxygen environment. Immediately after birth with the initiation of breathing, the lung expands and oxygen availability to tissue rises by twofold, generating a physiologic oxidative stress. However, both lung anatomy and function and the antioxidant defense system do not mature until late in gestation, and therefore, very preterm infants often need respiratory support and oxygen supplementation in the delivery room to achieve postnatal stabilization. Notably, interventions in the first minutes of life can have long-lasting consequences. Recent trials have aimed to assess what initial inspiratory fraction of oxygen and what oxygen targets during this transitional period are best for extremely preterm infants based on the available nomogram. However, oxygen saturation nomogram informs only of term and late preterm infants but not on extremely preterm infants. Therefore, the solution to this conundrum may still have to wait before a satisfactory answer is available.

No MeSH data available.


Related in: MedlinePlus