Pediatric Anesthesia Flashcards
Name the components of Tetrology of Fallot.
1- Overriding aorta
2- right ventricular hypertrophy
3- Pulmonary artery stenosis
4- VSD
What syndrome is highly associated with Tetrology of Fallot?
Trisomy 21
What are two coexisting diseases that have a high concordance with malignant hyperthermia?
Central core disease and King-Denborough syndrome
How does pyloric stenosis present?
- Presents between 2-6 weeks of age
- Males > females
- olive-shaped mass between the midline and RUQ
- gastric obstruction leads to projectile, nonbilious vomiting and electrolyte imbalance.
- a hypochloremic, hypokalemic, metabolic alkalosis with compensatory respiratory acidosis.
- with further fluid loss, prerenal azothemia may lead to severe dehydration, hypovolemic shock, and metabolic acidosis. Hypoglycemia may be present due to malnutrition.
- Treatment is a pyloromyotomy.
- Non-emergent surgery –> resuscitate with fluids and electrolytes. Aspirate stomach contents with OG tube prior to induction to minimize the risk of pulmonary aspiration –> MUST do RSI.
Preoperative fasting recommendations in infants and children:
- clear liquids
- breast milk
- infant formula or light meal
- solids
- clear liquids- 2 hours
- breast milk- 4 hours
- infant formula or light meal- 6 hours
- solids- 8 hours
Differences in respiratory physiology in children vs adults:
- oxygen consumption
- alveolar ventilation
- closing capacity
- total lung capacity
- FRC
- tidal volume
- oxygen consumption and alveolar ventilation are twice as high in infancy than in adulthood
- closing capacity is approximately half of TLC in infancy
- FRC and TLC are unchanged throughout life
Infant’s laryngeal anatomy
- infant’s larynx is more cephalad (superiorly) in the neck at the level of C3-4 vs C4-5, making airway obstruction by the relatively larger tongue more likely
- narrowest part of the infant airway is at the level of the cricoid cartilage as opposed to the rima glottidis in adults
- epiglottis of an infant is narrower and stiffer than that of an adult and omega-shaped and angled more posteriorly
Describe the Pierre-Robin sequence.
- micrognathia
- glossoptosis (the abnormal posterior displacement or retraction of the tongue)
- cleft palate
Patients with this syndrome may result in airway obstruction and difficult intubation due to a small anterior mandibular space, contributing to airway obstruction between the tongue and posterior pharyngeal wall.
Describe the AGPAR score.
Appearance Pulse Grimace Activity Respiration
T or F: elective surgery should be postponed whenever possible until after 54-60 weeks postconceptual age, at which point respiratory control is mature and no special measures need be taken in the otherwise healthy ex-premie.
True- a minimum of 12 hours of monitoring is recommended for ex-preterm infants
Describe omphalocele vs gastroschisis.
Omphalocele- twice as common as gastroschisis and occurs more frequently in premature infants. Associated with cardiac, GI, GU, Beckwith-Wiedeman syndrome. Small bowel are in a sac.
Gastroschisis- results from occlusion of the omphalomeseneric artery during gestation. No covering of the organs and a surgical emergency.
Describe congenital diaphragmatic hernia.
Usually left-sided, morbidity and mortality result from pulmonary hypoplasia and associated pulmonary vascular disease.
Gentle ventilation strategies that preserve spontaneous ventilation with low inspiratory pressure support (< 25 cm H2O) minimize lung distention and barotrauma and correlate with improved survival.
Permissive hypercapnia is considered acceptable as long as the pH remains greater than 7.25 and PaCO2 is less than 60 mm Hg.
What is the induction agent of choice in a patient with Tetrology of Fallot? Why?
In tetrology of Fallot, you want to make sure that you don’t drop preload with induction. Cyanosis occurs as a result of right to left shunting across the VSD. The degree of cyanosis is dependent on the degree of shunting which depends on systemic vascular resistance.
Ketamine maintains SVR and is the induction agent of choice in tetrology.
For a child with a recent URI, proceed with the case if:
1-
2-
3-
1- no thick secretions or fever
2- LMA or mask ventilation is planned
3- patient is not wheezing
T or F: airway reativity following a URI is increased for 4-6 weeks.
T- the incidence of bronchospasm, laryngospasm, hypoxia, atelectasis, and post-intubation croup is increased in patients with URIs, but this doesn’t impact morbidity. These problems are greatly increased with intubation and less with LMA and mask.
Formula for calculating ETT size
(age/4) + 4
Formula for calculating ETT depth
(age/2) + 12
(kg/5) + 12
3 x diameter of ETT
Describe post-intubation croup? What is the treatment?
Occurs secondary to airway swelling. Edema is self-limited, but impossible to know if it will get worse or better, so it is good treat with racemic epinephrine.
Racemic epinephrine helps to decrease swelling immediately by constricting exposed vessels.
What causes laryngospasm? What is the treatment?
Laryngospasm occurs secondary to superior laryngeal nerve stimulation, thought to be secondary to secretions falling on the glottis during the hyperarousal phase of volatile anesthesia. Treatment is positive pressure ventilation.
