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CHAPTER 10

Anaesthesia and Perioperative Care

Mark Newton
Stella A. Eguma
Olamide O. Dairo

Introduction hypovolaemia, such as during intestinal obstruction, many neonatal
The practice of providing surgical anaesthesia for children dates back emergencies, and delayed medical management for many surgical cases
to 1842, when Dr. Crawford Long used ether for an amputation on an because neonates cannot increase their heart rates sufficiently to over-
8-year-old boy. Since that event, many paediatric patients have been come the decrease in stroke volume.
administered anaesthesia with ether. Today, however, essentially all of Congenital heart disease (CHD) is common in the neonatal surgical
the anaesthetic drugs used in the adult population are used in paediat- patient in comparison to the normal population. Many congenital
rics. Major steps forward—such as the use of endotracheal intubation surgical problems have associated cardiac anomalies; therefore, any
(1936), the Jackson-Rees modification of the T-piece (1950), the pre- neonate presenting for surgery needs to have an appropriate cardiac
cordial stethoscope (1953), the use of muscle relaxants (1940s), and the exam. If a murmur is present, then a further work-up may be indicated
introduction of the newer inhalation anaesthetic agents (1960s)—have prior to surgical intervention, and anaesthetic adjustments must be
allowed the administering of anaesthesia to become safer. made in an effort to maximise the oxygen delivery and blood pressure.
Today, anaesthesia is provided for the paediatric patient on a A chest x-ray and oxygen saturation determination will help to
daily basis in many hospitals throughout the world, despite ongoing determine the need for further more specialised work-up, if available.
challenges. In Africa, for example, the paediatric patient presents for The need for antibiotic coverage perioperatively should be considered
surgery with a pathophysiological picture that can be very different in all patients with a cardiac defect. Currently, an antibiotic given
from that of a similar patient in the typical Western hospital setting. preoperatively either 60 minutes orally or 30 minutes intravenously
The addition of malnutrition, tropical diseases such as tuberculosis and (IV) will cover the risk of endocarditis. 1
malaria, delayed presentation, poor primary care, and chronic disease Respiratory Function
states can compound the acute surgical problem that is prompting The neonatal airway’s narrowest location is the cricoid cartilage and not
intervention. In many African settings, the basic hospital infrastructure, the vocal cords, as it is in the adult. Also, the glottis is more anterior,
theatre supplies, and essential monitoring equipment—all of which make with the epiglottis being less rigid, which tends to occlude the airway
paediatric anaesthesia safer—are commonly unavailable. Anaesthesia opening when attempting an intubation. All of these anatomical dif-
supplies appropriately sized for neonates and small children, such as ferences between a neonate and an adult can result in a more difficult
endotracheal tubes, blood pressure cuffs, and even small syringes that intubation when attempting to place the endotracheal tube, but with a
allow for safe anaesthesia care, are not available in many hospitals. skilled anaesthesia care provider, this also can become routine. The
These issues, as they relate to providing anaesthesia care for neonates induction and intubation of a neonate requires special care because the
and paediatric patients who require surgery in the African setting, oxygen saturation will decrease much faster than in an adult patient
challenge even the most skilled of anaesthesia care providers. due to the higher neonatal oxygen consumption and high minute ven-
This chapter provides an overview of some of the challenges when tilation/functional residual capacity (FRC) ratio in the neonate. A pre-
providing anaesthesia care for children in Africa. The chapter reviews mature infant will have an immature chemoreceptor ventilatory drive
the cardiac, respiratory, and renal differences of children in comparison and at times slow respiratory effort with an elevation in carbon dioxide
to adults. Additionally, it addresses preoperative assessment, including levels. For many premature infants, apnea, which is cessation of venti-
guidelines for nothing by mouth (NPO, or nil per os), general and lation for 20 seconds with bradycardia, can be a serious postoperative
regional anaesthesia, intraoperative monitoring, airway management, problem that needs careful monitoring. 1
and postoperative care. Renal Function
Differences in Anatomy and Physiology The newborn’s immature renal function can contribute to many fluid
and electrolyte problems in the surgical patient. Glomerular filtration
Cardiovascular Function
rates (GFRs) reach adult levels by 1 year of age, and the newborn’s
Neonatal myocardial function demonstrates a cardiac output that is
inability to concentrate urine certainly affects the ability of the newborn
relatively fixed due to the inability of the neonate to increase the stroke
to respond to times of hypovolaemia. The infant’s inability to balance
volume, which would allow for a higher cardiac output. The neonate
sodium levels appropriately prompts careful attention to the balance
cardiac muscle has fewer contractile elements per gram of tissue when
of sodium because the renal system’s immaturity results in an overall
compared to an adult heart; this affects the neonate’s ability to compen-
sodium loss.
sate for hypovolaemic states. Also, the parasympathetic nervous system
is more developed than the sympathetic nervous system until the age of Temperature Regulation
6 months, when the two systems become more balanced. This imbal- Temperature regulation differences result in the newborn having hypo-
ance in the autonomic nervous system in the neonate predisposes the thermic periods in the perioperative period. The infant’s relatively large
neonate to bradycardia during times of stress, even with simple airway surface area, inability to shiver, large head size (related to heat loss),
suctioning, and certainly during airway intubation attempts. This dif- and poor insulation can cause dangerously low temperature levels,
ference between the neonate and the adult is evident during times of which can cause hypoventilation and even cardiac arrhythmias. The