Premature birth: topics in physiology and pharmacological characteristics

Abstract

OBJECTIVE: To review the main physiological and pharmacological changes related to prematurity, to promote the evidence-based clinical practice.METHODS: This is a narrative review whose research was carried out in the ScienceDirect and Medline databases via PubMed, searching for articles in any language from January 2000 to February 2020.RESULTS: Premature newborns are born before completing the maturation process that prepares them for extrauterine life, which occurs especially in the last weeks of pregnancy. Therefore, they have their own characteristics in development. Several physiological peculiarities stand out, such as disturbances in glucose regulation, adrenal function, thermoregulation, immunity, in addition to changes in liver, renal and respiratory functions. Pharmacological aspects were also highlighted, involving pharmacokinetics and pharmacodynamics.CONCLUSIONS: Despite the recent advances in prematurity, it is still an area with many uncertainties, since several changes occur quickly and there are ethical issues that make studies difficult. Thus, it is clear that the therapeutic management of premature infants is still very much based on clinical practice.

Use of Antibiotics in Preterm Newborns

“…Physiologically, this transition depends on several factors that include maternal medical history, duration of pregnancy, placental condition, and presence of fetal congenital anomalies [ 30 ]. As consequence, the physiological characteristics of preterms can significantly affect the pharmacokinetic (PK) and pharmacodynamic (PD) behavior of different drugs, making these subjects a special population that deserves specific pharmacological consideration [ 31 ].…”

“…In newborns, the head represents almost the 20% of total surface area and is the main source of heat loss. Preterms are characterized by thinner skin compared to full-term neonates, and, similarly, the subcutaneous fat layer is not adequately developed to prevent evaporative heat loss [ 31 ]. Since shivering is a physiological process gradually acquired after the first year of life [ 32 ], newborns adopt a non-shivering thermogenesis based on brown-fat deposition and oxygen consumption.…”

“…In this regard, a recent review from Machado JS and colleagues (2021) reports several examples of specific drug classes whose actions are affected by the physiological changes observed in preterm neonates. For example, prokinetic agents may not be completely effective in preterms and only partially effective in full-terms due to an age-dependent expression of intestinal motilin receptors that regulate antral contractions [ 31 ]. Similarly, bronchodilator agents are ineffective in preterms because of the paucity of bronchial smooth muscles.…”

Association between Breastfeeding Attitudes and Postpartum Depression among Mothers with Premature Infants during COVID-19 Pandemic

“…If the benefits for a full-term infant are enormous, a preterm infant may be entitled to far more benefits of breast milk. Unfortunately, premature infants are the population at risk where these infants are born before completing the maturation process that equips them for extrauterine life, particularly in the latter weeks of pregnancy [2]. Preterm birth rates are rising in most countries [3]; in Malaysia, the prevalence increased from 8% in 2010 to 12.4% in 2015 [4].…”

“…Preterm birth rates are rising in most countries [3]; in Malaysia, the prevalence increased from 8% in 2010 to 12.4% in 2015 [4]. Hence, managing nutritional needs among premature infants by encouraging breastfeeding is mandatory to ensure reductions in physiological problems, despite the beneficial pharmacokinetics of several available drugs [2].…”