Clinical pharmacology of analgesics in infants and the pharmacologic management of pain in neonates

Abstract

The objectives of this study are to describe (1) the clinical pharmacology of analgesics in infants and (2) the pharmacologic management of pain in neonates. METHODS: The bibliographic search was performed using PubMed and EMBASE databases as search engines. RESULTS: Opioid analgesics are the most commonly used analgesics for acute pain and they include intravenous morphine (50 to 200 mg/kg), oral methadone (50 to 200 mg/kg), intravenous fentanyl (0.5 to 4 mg/kg), alfentanyl (10 to 20 mg/kg), sufentanil (10 to 15 mg/kg), and remifentanil (5 mg/kg). Fentanyl, alfentanyl, sufentanil and remifentanil are short-action opioid analgesics. Non-opioid analgesics can be used for moderate pain; they include oral paracetamol (acetaminophen, 12 to 15 mg/kg), the intravenous benzodiazepine midazolam (50 to 150 mg/kg) which is not recommended in neonates, intravenous propofol (2.5 mg/kg) which is used for induction of general anaesthesia, and ketamine, (2 mg/kg intravenously or 4 mg/kg intramuscularly) which produces a short-lasting, trance-like state with profound analgesia and amnesia. CONCLUSION: The use of non-opioid analgesics has increased in the last years for the management of non-acute pain. If prevention or elimination of pain is not possible, a more realistic goal may be to aggressively intervene to minimize pain and its effects.

Metabolism and pharmacokinetics of morphine in neonates: A review

“…Mechanically ventilated neonates (>24 hours) also had significantly higher morphine plasma concentrations. The control of pain by analgesics other than morphine has been recently reviewed elsewhere 17-19.…”

A great tool that resurfaced during the pandemic: Remifentanil

“…However, the elimination half-life does not change with age, with its average value being between 3.4 and 5.7 minutes, demonstrating rapid clearance similar to adults. [15][16][17][18] The increased volume of distribution is due to the higher percentage of total body water and higher circulating volume in the pediatric age. The increased clearance may be explained by the fact that neonates and infants have a more remarkable ability to metabolize drugs due to their relatively large liver size or increased hepatic blood flow.…”

Antiepileptic Drugs Cause Lethal, Sublethal, Teratogenic Effects and Morphometric Parameters on Embryos and Larvae of Zebrafish (Danio Rerio)

“…However, these same properties are responsible either for bioaccumulation and toxic effects in aquatic and terrestrial ecosystems (Santos 487 et al, 2010). GAB is eliminated from the systemic circulation by renal excretion (FDA, 2011), and intestinal excretion (Prasad, 2019) as unchanged drug and is not appreciably metabolized in humans (FDA, 2011), a quarter of the administered dose of PB is excreted unchanged in the urine in neonates and adults (Pacifici, 2014), and intestinal excretion (Yumiko et al, 2019), 2% of OX is excreted unchanged by the body, as well as carbamazepine and intestinal excretion (Bahlmann et al, 2014).…”