Introduction:
Pediatric patients are very vibrant kinds of patients who require care to handle. They are different from adults in many aspects. They are different from absorption to metabolism to excretion. They are different physically and mentally also. Being so different makes them go through special care in hospitals and operation theaters.
What Is Pediatric Anesthesia?
Pediatric anesthesia is anesthetics given to a neonate, infant, or child for surgery they require. Although pediatric patients have immaturely developed body functions, with the proceeding age, their different body functions start developing and forming into an adult. So, before giving a dose of anesthesia, a few preoperative measures need to be understood, as this patient needs particular concern.
Neonates are zero to 30 days old, infants are one-month-old newborns, and children are more than one year old.
How Is a Child Different From an Adult?
There is a difference between a child and an adult, physically, mentally, and anatomically. A few differences are mentioned:
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The head is larger than the adult's as compared with the total body ratio.
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Children's tongues are large.
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The nasal passages of children are narrow.
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Children are obligate nose breathers until five months of age.
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Children's airways have a short and stubby epiglottis with a highly located larynx (C2-3) and angled vocal cords. At the same time, adults have broader epiglottis and vocal cords more perpendicular, with a larynx (C4-5).
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On looking at their respiratory system, they have tiny alveoli with limited numbers. The chest is circularly shaped with horizontal ribs. Weaker intercostal muscles have a significant oxygen consumption rate, and the trachea is short.
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In the cardiovascular system, the myocardium is less contractile to generate tension in ventricles and limits the size of stroke volume and cardiac output rate being dependent.
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In kidneys, decreased glomerular filtration rate.
What Is the Preoperative Checklist for a Pediatric Patient?
Before going for surgery, the pediatric patient requires setup in operation theaters. It includes:
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Increase the temperature of the operation theater to warm where the surgery will take place
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Overhead warming lights are to be kept on.
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Age-appropriate headrests and monitors.
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Peds Bair hugger.
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See for the IV set up in the room.
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The patient should have been given premedication if required.
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Go for latex-free gloves.
What Are Important Pharmacokinetic Points for Pediatric Patients?
Children and newborns react differently to anesthetic drugs because they vary in many aspects, from body temperature to body organ function. For example, in talking about neonates' body composition, 80 % of their bodies are filled with water. However, with the passing of age, as they become infants to one year, their body water content comes to 60 % of the body, and their fat content increases. So this clarifies that water-soluble drugs require larger doses. In addition, as the immature body has immature kidney and liver functioning, thus the metabolism and excretion of some drugs get slow and lead to prolonged elimination.
Body temperature in newborns is an initial and important step to be noted because it slows the metabolism and excretion of the drugs.
How Is an Anesthetic Used in Pediatrics?
Before encountering patients with anesthetic, the doctor notes a few crucial points, which include:
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Physically examining the patient.
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Have a family history of anesthetic.
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Drug allergy.
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Any specific medical allergy.
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There are essential pre-anesthetic fasting guidelines for pediatric patients. Before the pre-anesthetic is given, child fasting is necessary. If the child has breastfed, he should fast for a minimum of four hours, and if a child has solid food, he should have a minimum of eight hours of fasting, formula milk, then six hourly fastings are required.
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This phase is essential to ensure the patient is relaxed and his body functioning is reasonable to proceed with the further step.
Soon after checking, the anesthetic is given to the patient calmly (for example., sedatives, analgesics, anticholinergic). Then, during the induction phase of the drug - there are many ways of inducing anesthesia, but we mainly use inhalation.
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Inhalation of volatile anesthetic agents is mainly preferred over intravenous ones. Face masks do inhalation; it begins when the patient starts inhaling it through the mask, and there is a high gas flow of oxygen mixed with the nitrous oxide. It leads to the unconscious being of the patient, and surgery can be performed.
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Intravenous is usually not given, and if required, after inhalation is performed, Thiopentone sodium is generally used.
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Intraosseous.
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Saphenous.
Soon after induction, a phase called the maintenance phase comes. The maintenance phase is present between the induction phase, and the surgery is started. In this phase, the child is unconscious and unresponsive; accordingly, drugs are used to give muscle relaxants or other medications for surgery. But mostly nitrous is enough to go with, and it is safe too. During the reversal period, volatile agents leave the lungs, and monitoring of the drugs is observed by the doctor.
What Drugs Are Used in Pediatric Anesthetics?
General anesthesia is used in many cases. The commonly used anesthetics are:
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Volatile Agents - Halothane, Isoflurane, Sevoflurane, Desflurane, and Enflurane.Volatile anesthetics have a rapid onset of action and are convenient to use. Among these, Isoflurane and Sevoflurane are commonly made use. But they have side effects; they depress the ventilation and contract bronchial, arrhythmias, and hepatotoxicity. Halothane has high solubility and was used earlier, but because of its slow onset and increased risk of arrhythmias and hepatotoxicity, it is not used nowadays. Isoflurane and Sevoflurane are used together in combination for inducing and maintaining subsequently.
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Intravenous and Intramuscular Drugs - Although it becomes difficult to operate IV and IM in pediatric patients, more convenient inhalation is preferred. Ketamine, Benzodiazepines (Midazolam), Propofol, opioids, and muscle relaxants (Succinylcholine, Rocuronium) are used.
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Opioids - Opioids are commonly used as a premedication and can cause apnea and respiratory depression. Morphine and Fentanyl are also used frequently.
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Benzodiazepines - Midazolam works superbly and can be administered in other ways too. The side effects as compared to volatile drugs are less, but they are combined and used along with these for the maintenance period.
Is Regional Anesthesia Also Used in Pediatrics?
Yes, there are general, local, and regional anesthesia. All are used in pediatrics; those mentioned above are the general anesthesia and regional being caudal, SAB, and penile block.
Caudal block is used in penile and anal surgery, vaginal, orchidopexy, and hernia repair.
Bupivacaine and Lidocaine are also used.
What Are the Complications of Pediatric Anesthetic Drugs?
Complications are:
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Postoperative vomiting and nausea.
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Respiratory depression.
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Decreased cardiac output.
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Arrhythmias.
Anaphylaxis:
The Ring and Messmer clinical severity scale, cited by Dewatcher et al., distinguishes the following reaction levels:
Grade 1: Cutaneous mucous signs: erythema, urticaria with or without angioedema;
Grade 2: Moderate multi-visceral signs: cutaneous mucous signs ± hypotension ± tachycardia ± dyspnea ± gastrointestinal disturbances;
Grade 3: Life-threatening mono-or multi-visceral signs: cardiovascular collapse, tachycardia, or bradycardia ± cardiac dysrhythmias ± bronchospasm ± cutaneous mucous signs ± gastrointestinal disturbances;
Grade 4: Cardiac arrest.
Conclusion:
Pediatric anesthesia is not just a game of a few drugs; it requires patience and proper management to deal with the little ones. As children are different in anatomy, physiology, and psychology, the pharmacology used by pediatric patients also varies. Therefore, physical examination and fasting of the child are required before anesthesia. Usually, doctors prefer to go for volatile inhalation agents as an anesthetic.
