Infant Exposure To Anaesthetic Drugs Biology Essay

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

The techniques of anesthetizing adults must be modified for a pediatric patient. Many of the differences are important to the anesthesiologist. The child's nervous system is not fully developed, so certain reflexes which are active and present in adults are absent in the newborn. For children in particular, too much anesthesia can cause patients to slip into a coma and die, either during the surgery as well as afterwards (CBC, 2007). Recent inquiries into how these strange chemicals act on the cellular level have uncovered a troubling long-term possibility: that general anesthetics may potentially contribute to cognitive impairment in vulnerable patients such as the very young and the very old (Harrell, 2009). According to Harrell (2009), in 2007, Dr. Zhongcong Xie and colleagues published the first in a series of studies 'demonstrating that commonly used general anesthetics can cause cell death and plaque accumulation in brain cells ' both potential hallmarks of dementia and Alzheimer's disease.'

One specific topic of interest is whether anesthesia can affect children and infants' bodies. Mayo Clinic researchers (2009) have found that children who require multiple surgeries under anesthesia during their first three years of life are at higher risk of developing learning disabilities later. The research team, led by Robert Wilder, M.D., Ph.D., a Mayo Clinic anesthesiologist (2009), 'found that although one exposure to anesthesia was not harmful, more than one almost doubled the risk that a child would be identified as having a learning disability before age 19.' The risk also increased with longer durations of anesthesia. Children's brains are more vulnerable to a variety of problems because they are undergoing dynamic growth (Mayo Clinic, 2009). The brain is swiftly forming connections between cells and trimming excess cells and connections (Anand, 2004).

When a patient goes into surgery, they are more than likely to be administered anesthesia to make the experience more comfortable and painless. Anesthesiologists are physicians who focus on surgical and pain relief of patients. They administer anesthetics, which prevents patients from feeling pain and sensations, closely monitor patients' vital signs during surgery and adjust anesthetics accordingly. The anesthesiologist will evaluate the medical records and history of the patient to figure out the dosage amount. The type of anesthesia administered depends on the type of surgery and medical history. There are various forms of anesthesia that include local, general and regional. Local anesthesia is medication used to temporarily stop the sense of pain in a particular area of the body. When this anesthetic is used, the patient is conscious and aware of what is going on. The opposite of local anesthesia is general anesthesia, where the patient will be unconscious during surgery. The anesthetic is usually administered through an intravenous line (IV) but it can also be inhaled through a breathing mask. An intravenous line is a thin plastic tube that is inserted into a vein, usually in the patient's forearm ('Types of Anesthesia,' 2008). The entire body is numb so the patient is unable to feel any pain. When compared to a regional anesthesia, patients are more likely to choose to use a regional anesthetic because it is easier to recover from.

Regional anesthesia is used for many types of procedures and operations but it is usually used when only one area of the body needs to be anesthetized. There are several types of regional anesthesia. Peripheral Nerve Blocks is a local anesthetic which is injected near a specific nerve or group of nerves to block pain from the area of the body supplied by the nerve. Epidural and Spinal Anesthesia is a local anesthetic which is injected near the spinal cord and nerves that connect to the spinal cord to block pain from an entire region of the body. Once injected, the medicine mixes with spinal fluid in the lower back and numbs the nerves it contacts, effectively blocking sensation and pain. The anesthesiologist can also use a variety of nerve blocks to ensure comfort throughout the procedure.

Harrell (2009) found that the 'role of calcium in the brain is critical, particularly in infants, whose brains undergo rapid neural development from the last trimester in uteri up through ages 1 to 2.' Infants' brains expand quickly, then ruthlessly prune back brain cells ' a process of orderly cell death known as apoptosis. In an experiment in young rats undergoing this crucial stage of neural development, Christopher Turner, an assistant professor of neurobiology and anatomy at Wake Forest University School of Medicine, witnessed out-of-control apoptosis in brains of rats treated with drugs that mimicked the action of the general anesthetic ketamine. Starved of calcium, whole portions of the rats' brains died off ' enough to cause significant cognitive impairment. In adult rats, the effect was much less severe. "There is something about the young brain that makes it exquisitely sensitive to the loss of calcium," says Turner, who was the first to propose that calcium depletion is a critical first step in drug-induced brain-cell injury (Harrell, 2009).

One study, completed at the Baylor College of Medicine, showed that babies who had the chance to play often and who were held and touched often as infants have larger brains with more neural pathways than children who received less attention and care when they were babies ('New Research,' 2010). According to Creeley and Olney (2010), 'There are many nerves and connections within the brain that are connected and functional only during the infancy and toddler age. The brain development in children occurs due to the genes and the environment of the growing child.' A child's first three years can act like the roadmaps to later learning. A baby's brain develops so fast that by age two; a child who is developing normally has the same number of connection as an adult. By age three, a child has twice as many brain connections as an adult.

According to Mayo Clinic (2009), 'Young children's brains are more vulnerable to a variety of problems because they are undergoing dynamic growth. The brain is rapidly forming connections between cells and trimming excess cells and connections, says Dr. Wilder.' According to Adriani (1964), 'The chest wall is thin, soft and underdeveloped. The air passages are much smaller and therefore, more easily become obstructed with secretions. Infants have little body fat and are more prone to lose heat by conduction and convection.' The bones are not fully developed and are easily injured because they are soft. The soft parts of the body of infants and children are easily traumatized (Adriani, 1964). When it comes to an infant's respiratory system, their air passages are smaller and still developing so it is more easily to become blocked with secretions. In Anesthesia for Children and Infants, Adriani (1964) states: 'The liver function of the newborn is not fully developed. Most drugs are destroyed by the liver or, if not attacked by the liver, are eliminated by the kidneys.' Consequently when the anesthesiologist administers drugs into the infant, drugs that depend on the liver may create abnormal responses.

About 1.5 million fetuses or newborns are exposed to anesthetic agents each year (Anand, 2004). Studies in 2003 show that drugs used in general anesthesia kill brain cells in developing rats and mice. According to Anand and Soriano (2004), 'Though these studies require follow-up with human populations, some have theorized that the dangers of anesthesia used in children may be greater than previously estimated. One might not only risk death but also interference in brain development, and perhaps long term memory issues or learning disabilities.' After their initial report in Science2 suggesting that anesthetic drugs such as nitrous oxide, ketamine or other N-methyl-D-aspartate receptor antagonists lead to enhanced apoptosis in immature neurons, Olney et al. have reported that newborn rats exposed to commonly used anesthetic agents also develop neurodegenerative changes in multiple areas of the brain, associated with long-term deficits in learning and memory (Anand, 2004).

Multiple surgeries increase the risk of developing a learning disability and/or effect brain development in the infant. Other studies have linked anesthesia exposure in young children to behavioral problems. Dr. Flick says the Food and Drug Administration (FDA) is aware of the possible problems with anesthesia. The FDA is also working to construct a study that compares children that had an anesthetic to those children who did not have an anesthetic with the same medical condition (Mayo Clinic, 2009). According to Mayo Clinic (2008),

Children under the age of three who had hernia surgery showed almost twice the risk of behavioral or developmental problems later compared to children who had not undergone the surgery, according to a study by researchers at Columbia University Mailman School of Public Health and the College of Physicians and Surgeons.

The study shows that children who had hernia surgery with the general anesthesia had twice the likelihood of developing behavioral problems. Some of the more serious problems in infants and newborns are: 'rapid respirations with diminished tidal exchange, periods of vomiting resulting in electrolyte imbalance, lung conditions that cause cyanosis, cystic hygromas of the neck, and anomalies of the great vessels,' according to Lank (1959). These surgeries can look devastating and overwhelming but with good anesthesia techniques, pre and postoperative care and high-quality surgery, these infants grow up to be normal, healthy people.

Most operations that are done to infants are in urgent situations, so these infants usually present more complications. Therefore, the anesthesiologist and nurse have to recognize any physiologic changes that can occur and be able to treat any complications. The anesthesiologist usually has little experience with this particular group of people, so if an emergency occurs, he or she is required to make a life or death decision. This can lead to many unnecessary deaths (Lank, 1959).

According to Anand (2004), 'It has been taught and widely accepted that open-cone ether is the best type of general anesthesia for pediatric surgery. This statement is not only dogmatic but untrue.' Ether is the safest of the inhalation anesthetics for pediatric surgery. As with ether, cyclopropane is acceptable for pediatric anesthesia. Ether is prone to cause greater accumulation of acids in the blood in infants, but cyclopropane is not. Chloroform is rarely used; not only is it toxic but also the possibly of producing damage to the liver is greater than with any other anesthetic (Anand, 2004).

There are many dangers of anesthesia, but risks are often outweighed by significant benefits. The dangers of anesthesia increases in infants and young children who had multiple surgeries and was administered a general anesthetic. Further studies are being conducted to determine whether the anesthesia is the reason for the increase in developing learning disabilities and behavioral problems in infants, as well as newborns. However, many infants can be brought safely through surgery without any complications. It is important for parents to know the effects of anesthesia in infants and be aware of the risks. Anesthesia is both necessary and useful, but the possibility of anesthesia causing brain damage in infants should put up a red flag to parents.