Neonate 2 - Emergencies Flashcards
Describe the 5 types of tracheoesophageal atresia.
Esophagheal atresia is the most common congenital defect of the esophagus and most of these children have a TEF
A- neither pouch connects to trachea B - Top pouch connects to trachea C - Bottom pouch connects to trachea D - Both pouches connect to trachea E - Singular esophagus that connects to trachea at one point
Which type of TEF is most common
Type C is most common (accounts for 90%)
The upper esophagus ends in a blind pouch and the lower esophagus communicates with distal trachea
What prenatal findings suggest esophageal atresia? How is diagnosis confirmed?
Esophageal atresia prevents the fetus from swallowing amniotic fluid, this maternal polyhydramnios is key diagnostic factor.
Confirmed by inability to pass gastric tube into stomach.
Other symptoms: choking, coughing, cyanosis during feeding
What is VACTRAL association?
Approx 25-50% of children with TEF have other congenital anomalies
V - Vertebral defects A - imperforate Anus C - Cardiac anomalies T - TEF E - Esophageal atresia R - Renal dysplasia L - Limb anomalies
A patient has type C TEF, were should the ti of the ETT be placed?
Below fistula and above carina
If placed too high - gas delivered to stomach
If placed too low - endobronchial intubation likely
How should you induce a patient undergoing type C TEF repair?
- Head up position and frequent suctioning to minimize risk of gastric aspiration
- Awake intubation or inhalation induction with spontaneous ventilation
- PPV -> gastric distention -> decreased thoracic compliance -> Increased PIP required to ventilate -> downward spiral
- Placement of G-tube allows for gastric decompression. If pt already has G-tube, open to atmospheric pressure
- Place ETT below fistula and above carina
- Right lung compression during surgical repair is common. Right mainstream intubation will cause rapid desat
Discuss pathophysiology of respiratory distress syndrome
Neonates who do not produce enough surfactant are at risk for RDS
- In absence of adequate surfactant, the alveoli remain stiff and noncompliant
- Small alveoli tend to collapse
- Larger alveoli become distended (accept gas from collapsed alveoli)
- This promotes atelectasis, reduces the surface area where the gas exchange can take place - creating a V/Q mismatch
- Hypoxemia leads to acidosis and possibly return to fetal circulation
What tests can be done to test fetal lung maturation in utero? what value suggests adequate lung development?
Amniocentesis can assist in the determination of fetal lung development
- Ratio of lecithin to sphingomyelin (L/S ratio) gives advanced warning about the state of the fetal lung by providing the ratio of lecithin (surfactant) to sphingomyelin (surfactant precursor)
- An L/S ratio of >2 suggests adequate lung development
Discuss the use pf pre and postductal SpO2 monitoring in the newborn
Preductal pulse ox placed on right upper ext
Postductal placed on either lower ext
Difference between pre and postductal values suggest
- palm HTN
- right to left cardiac shunt
- return to fetal circulation via the PDA
Pt has a hernia at the foramen of Bochdalek. Which congenital condition does this patient have?
Congenital diaphragmatic hernia - allows abd contents to enter thoracic cavity
foramen of Bochdalek is most common site of herniation (usually left side)
What S/S suggest congenital diaphragmatic hernia
CDH usually diagnosed at birth.
Newborn will have scaphoid abd (sunken in) and likely in respiratory distress
Other findings
- Barrel chest
- Cardiac displacement
- Fluid filled GI segments in the thorax
Discribe ventilatory management in patient with CDH
Mass effect of abd contents within the chest impairs lung development, leading to pulmonary hypoplasia. One or both lungs can be effected (increased PVR and decreased compliance)
- Keep PIP <25-30 to minimize barotrauma and risk of pneumothorax in “good lung”. This may require permissive hypercapnia
- Avoid other conditions that increase PVR (hypoxia, acidosis, hypothermia)
- Abd closure may increase PIP
- Pulse ox on lower ext van warn of increased intra-abd pressure
Omphalocele
Location: Organ involvement: Covering?: Incidence: Co-existing disease: Surgery:
Location: midline (involves umbilicus)
Organ involvement: Bowel & sometimes liver
Covering?: Yes
Incidence: 1 : 3,000-10,000
Co-existing disease: Trisomy 21, cardiac defects, Beckwith-Weidmann syndrome
Surgery: less urgent, requires cardiac workup first
Gastroschisis
Location: Organ involvement: Covering?: Incidence: Co-existing disease: Surgery:
Location: off midline (usually right)
Organ involvement: Bowel
Covering?: No
Incidence: 1: 30,000
Co-existing disease: Prematurity
Surgery: More urgent (within 24 hrs), higher risk for fluid & heat loss, IVF 150-300 ml/kg/day
Describe anesthetic concerns for patient with omphalocele or gastroschisis
If gastroschisis, abd contents placed in bag after delivery (minimized heat/water loss)
Monitor peak airway pressure: if PIP > 25-30, surgical closure of abd may need to be staged
closure may increase intra-abd pressure: increased abd pressure -> decreased venous return -> decreased CO -> decreased systemic perfusion
Measure SpO2 on the lower ext to monitor for impaired venous return
N2O dissents bowel and may impair surgical closure
Expect major fluid and electrolyte shifts
