Neonatal/Newborn Disorders

7.2
Neonatal/Newborn Disorders

  • This section covers basic medical management of neonatal disorders and long‐term sequelae which may affect the patient and their anesthetic management into childhood and beyond

Premature Birth

  • Live infant delivered before 37 weeks
  • Gestational age (GA) and birth weight (BW) are used to predict morbidity/mortality (Figure 7.3)
    Two diagrams. 1. Gestational age includes preterm birth, term birth, and post-term birth. 2. Birth weight includes extremely low birth weight, very low birth weight, low birth weight, and normal.

    Figure 7.3

  • Etiology/Risk Factors
    • 70–80% result from preterm labor or premature rupture of membranes
    • 20–30% are initiated by health care providers because of health concerns for mother or child
    • Maternal risk factors:
      • Prior preterm birth
      • <17 or >35 years of age
      • Lower socioeconomic status
      • Short interpregnancy interval
      • Overweight
      • Underweight or low gestational weight gain
      • Conception by assisted reproductive technology
      • Pregnancy with multiples
      • Substance use, including smoking
  • Prevalence
    • 5–18% of births worldwide
    • Varies by race and ethnicity in US. Below stats according to Center of Disease Control:
      • Non‐Hispanic Blacks 14.1%
      • Hispanic 9.7%
      • Non‐Hispanic White 9.1%
    • Associated with 30% of all infant deaths in US
  • Treatment
    • Benign to symptomatic
    • Depends highly on BW and GA
  • Primary Concerns
    • ↑ Risk of bronchopulmonary dysplasia (BPD) and subsequent reactive airway disease
    • ↑ Risk of pulmonary hypertension
    • ↑ Risk of developmental disabilities
    • ↑ Risk of CHD
    • ↑ Risk intraventricular hemorrhage
  • Evaluation
    • History
      • GA at birth
      • Time in NICU
      • Need for supplemental oxygen, intubation, mechanical ventilation
      • Home use of apnea monitors
      • Persistent respiratory symptoms
    • Consider cardiologist consult if congenital heart defect is present
  • Anesthesia Management
    • ↑ Suspicion for airway reactivity
      • For bronchospasm management see page 260
    • Consider tracheomalacia if prolonged intubation in NICU

Respiratory Distress Syndrome (RDS)

  • Etiology/Risk Factors
    • Premature Birth
    • C‐section
    • Maternal diabetes
    • Infection
    • Rare in infants born after 30 weeks
  • Pathophysiology
    • Deficiency of pulmonary surfactant, which decreases alveoli surface tension, in immature lungs (Figure 7.4)
    • Presents within minutes to hours of birth
      • Rapid and shallow breathing
      • Nasal flaring
      • Grunting
      • Tachypnea
      • Progressive cyanosis and dyspnea
      • Ultimately acidosis, hypotension, temperature instability, and apnea
    • Treatment
      • Goal of maintaining SpO2 > 90%
      • Warm, humidified oxygen
      • Nasal CPAP
      • Exogenous surfactant via ETT
      • Mechanical ventilation
      • If uncomplicated, will resolve in three to four days
      • Chronic disease can develop if oxygen requirement persists
    • Primary Concerns
      • Occurs in 75% infants born before 28 weeks GA
      • May produce respiratory symptoms throughout childhood
    • Evaluation
      • History
        • NICU course
        • Requirement for supplemental oxygen and mechanical ventilation
        • Persistent respiratory symptoms
    • Anesthesia Management
      • ↑ Suspicion for airway reactivity
        • For bronchospasm management see page 260
      • Consider tracheomalacia if prolonged intubation
17–28 weeks GA Alveoli begin to form
28–36 weeks GA Pulmonary capillaries form:
Beginning of alveolar‐capillary barrier
32–34 weeks GA Surfactant production by type II pneumocytes
A diagram of laplace's law indicates the following. 1. Radius. 2. Pressure to keep sphere open. 3. Surface tension.

Figure 7.4

Bronchopulmonary Dysplasia (BPD)

  • Etiology/Risk Factors
    • The main chronic complication of RDS
    • Preterm birth
      • Incidence ~40% in infants born before 28 weeks
    • Prolonged ventilation and oxygen therapy
    • Male gender
    • Some evidence for maternal smoking
  • Pathophysiology
    • Exposure to mechanical ventilation and requirement of supplemental oxygen beyond 28 days of life
      • Disrupts pulmonary development and causes lung injury
    • Elevated oxygen requirement
    • ↓ Lung compliance
    • Reversible airway obstruction
  • Treatment
    • Adequate nutrition
    • Respiratory support as required
    • Diuretics
    • Inhaled and systemic corticosteroids
    • Bronchodilators
    • Most patients improve gradually as growth continues and healing occurs
  • Primary Concerns
    • Pulmonary symptoms persist for months to years
    • Children who survive BPD have double the incidence of motor and cognitive delays [5]
  • Evaluation
    • Records
      • Patient may have been followed by BPD clinic
    • History
      • Persistent respiratory symptoms
      • NICU course
      • Requirement for supplemental oxygen and mechanical ventilation
      • Persistent respiratory symptoms
  • Anesthesia Management
    • ↑ Suspicion for airway reactivity
      • For bronchospasm management see page 260
    • Consider tracheomalacia in younger children who required mechanical ventilation

Apnea of Prematurity (AOP)

  • Cessation of breathing for more than 20 seconds or shorter pauses associated with desaturation and/or bradycardia
  • Etiology/Risk Factors
    • Underdeveloped diaphragm
    • Premature birth
    • Hypoglycemia
    • Hypoxia
    • Anemia
    • Hypothermia
    • Sepsis
  • Pathophysiology
    • Blunted chemoreceptor response to hypercarbia and/or hypoxia (Figure 7.5)
  • Treatment
    • Treat and rule out possible underlying issues
      • Anemia
      • Infection
      • Hypoglycemia
      • Drugs
      • IVH
      • NEC
      • Upper airway anomalies
      • Seizures
      • Feeding difficulty
    • Head and neck positioning
    • Prone positioning
    • Supplemental oxygen
    • CPAP
    • IV or oral caffeine or theophylline administration
    • Can be discharged to home without monitoring after 7–10 days free of apneic episodes
    • Not a risk factor for SIDS
  • Primary Concerns
    • Almost all infants born before 28 weeks GA are affected
    • Usually resolves by 36–37 weeks GA
  • Evaluation
    • History
      • Perinatal course
      • Requirement for supplemental oxygen and mechanical ventilation
      • Home apnea monitor use
  • Anesthesia Management
    • Incidence of postoperative apnea drops significantly after 35 weeks GA
    • Consider tracheomalacia in younger children who required mechanical ventilation
    • No known data/literature to guide perioperative management once AOP resolves.
A table has 2 columns and three rows of types of apnea of prematurity. The row headers are central, obstructive, and mixed. Most apnea of prematurity episodes are central or mixed.

Figure 7.5

Retinopathy of Prematurity (ROP)

  • Visual impairment beginning in the neonatal period
  • Etiology/Risk Factors
    • Injury or premature birth disrupts normal angiogenesis
    • Premature birth
    • Hypotension
    • Hypoxia
    • Hyperoxia
  • Pathophysiology
    • 15–18 weeks GA
      • Retinal vascularization begins
    • 36–40 weeks GA
      • Vascular development complete
    • AAP guidelines suggest screening for all infants BW < 1500 g or GA < 30 weeks
  • Treatment
    • Based on disease severity
  • Primary Concerns
    • ↑ Risk of retinal detachment
  • Evaluation
    • History
    • Consider ophthalmology consult
  • Anesthesia Management
    Only gold members can continue reading. Log In or Register to continue

Related posts:

  1. Mapleson Circuit
  2. Glucocorticosteroids
  3. Valvular Disease
  4. Tracheostomy
  5. Renal
  6. Endotracheal Tubes (Figure 9.14)

Stay updated, free dental videos. Join our Telegram channel
Tags:
Oct 16, 2024 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Neonatal/Newborn Disorders

VIDEdental - Online dental courses
Get VIDEdental app for watching clinical videos