NEONATAL PAIN: FICTION OR REALITY?

For years there has been a belief that newborns perceive pain less and tolerate it better due to their biological immaturity. It was also thought that the inability of infants to verbalize their feelings and express their pain was synonymous with an inability to experience and remember it.

To this must be added that in children the response to pain often does not differ from other responses, such as fear and stress, to other non-painful situations.

Therefore, it was not uncommon to hear by many health professionals phrases such as: “In infancy less pain is experienced”, “Neonates do not remember the experience of pain”, “Children cannot locate or describe their pain ‘ or even ’Pain helps to build character”.

BUT THE OPPOSITE WAS TRUE.

ARE MORE SENSITIVE TO PAIN THE YOUNGER THEY ARE

There is currently sufficient data to affirm that the neonate is capable of feeling pain. From before 28 weeks of gestation, the fetus has developed the anatomical, neurophysiological and hormonal components necessary for the perception of pain, but with a drawback that makes them even more vulnerable; and that is that many inhibitory mechanisms (with which we manage to “tolerate pain” or mitigate it physiologically) will not develop until several weeks or months after birth, which implies that newborns have a more intense pain response to the same painful stimulus than older children and adults, and that is because there is a lower pain threshold at a lower gestational age.

It is also possible that they have a higher concentration of substance P receptors. They have a lower threshold of excitation and sensitization, which leads to greater central effects with nociceptive stimuli. These factors seem to be responsible for the fact that the painful sensation is more severe in children than in adults.

CONSEQUENCES OF UNTREATED PAIN IN THE NEWBORN

The prevention of pain in these infants is important not only for ethical reasons, but also because of its short- and long-term consequences.

In the short term, they experience an increase in catabolism (and oxygen consumption), blood pressure, intracranial pressure and stress hormones (catecholamines, cortisol, glucagon); which together with the decrease in oxygen saturation and insulin secretion (which lead to an increase in glucose levels that can be harmful to the immature brain) lead to an increased risk of neurological damage and an increased susceptibility to infections, due to the depression of the immune system resulting from stress.

In the long term, studies suggest that early painful experiences may trigger exaggerated affective-functional responses to later painful experiences, and contribute to neurodevelopmental disturbances (sleep, behavioral, cognitive and learning development).

TREATMENT OF NEONATAL PAIN

There are many acute painful stimuli, often recurrent, that are performed during the care of the NB for diagnostic or therapeutic purposes (blood extraction, cannulation of tracts,...), care procedures (placement of probes, postural changes, removal of adhesive tapes) or explorations. Neonates in the incubator, in addition to the ability to perceive pain, are able to recognize suffering, anxiety and fear. Therefore, we must be clear that their treatment is absolutely necessary.

There are a series of non-pharmacological measures (preventive, environmental and behavioral) that can provide adequate analgesia in mild pain, and even when used together with analgesics, they enhance its efficacy. However, there are occasions when these resources are insufficient and we have to resort to pharmacological measures. The most commonly used drugs are local anesthetics, opioids and non-steroidal anti-inflammatory analgesics. On the other hand, there are stressful situations that are not painful for the neonate, in which the appropriate treatment is sedation and not analgesia.

“MAKE PAIN VISIBLE AND MAKE PAIN MATTER”

Although in recent years there has been increased interest in pain in the neonatal period, measures to prevent pain in the newborn are applied in only a small percentage of cases. As in other aspects of newborn care, there continues to be a wide gap between what is known and what is done. Raising awareness, both in the national health system and in society, is essential to ensure that strategies for the prevention and treatment of pain in the newborn are integrated into daily clinical routines.

From Sedalux we want to make the problem of infant pain visible and make it matter. But not only that: we are going to fight it and act in a proactive, integrated and global way, in order to achieve a better approach to pain in all its different aspects: prevention, detection and treatment; in order to improve its care at all levels.

¿ANESTHETIST or ANESTHESIOLOGIST?

Although “anesthetist” and “anesthesiologist” are used interchangeably in many contexts and even the Dictionary of the Royal Spanish Academy of the language considers it valid to use both nouns as synonyms, in medical language and among specialists in Anesthesiology and Resuscitation a distinction is preferred between the two terms.

According to the Spanish Society of Anesthesiology, Resuscitation and Pain Therapy (SEDAR), an anesthesiologist is one who has completed a career in general medicine and has subsequently specialized in this branch by completing a period of specialized M.I.R. training in anesthesiology, pain management and perioperative intensive care (or “resuscitation”). In some countries, such as Spain, the term anesthesiologist is also used to refer to a physician specializing in anesthesiology; however, in many other Spanish-speaking areas (America and Latin America) this term is used to refer to other types of healthcare personnel (nurse anesthetist, technician or anesthesiologist assistant) who practice anesthesia without medical qualifications, usually under the supervision of anesthesiologists.

So, although it may seem somewhat confusing, in these areas anesthesiologists usually work under the supervision of an anesthesiologist and that is why our professional society, SEDAR, prefers the term anesthesiologist to be used to refer to specialized physicians.

On the other hand, it should be added that the term anesthesiologist, used in the 19th century and until the first half of the 20th century, which referred to those who administered anesthesia during surgical procedures, usually practitioners, medical students or self-taught physicians, is now considered to be in disuse.