Transcript Successful” treatment of patients with obesity

Congenital Diaphragmatic
Hernia
Jeff Wu
Pediatric Surgery Clerkship, David Geffen SOM at UCLA
March 8, 2006
ID/CC: 38 4/7 week gestation newborn male NSVD to 31 y/o mother.
PMHx: patient antenatally diagnosed with CDH at 28 weeks.
Infant intubated in delivery room
Placed on conventional mechanical ventilation
PE: Right-deviated trachea; diminished breath sounds on L; abdomen
scaphoid
pH of 6.74, pCO2 of 111, pO2 of 98, bicarbonate 14.8, oxygen
Saturation 82%, and base deficit of -22.
High-frequency oscillator: Mean airway pressure of 18, FiO2 100%,
Nitric oxide 20 ppm. Amplitude was 38 to 42 and freq 10 Hz.
O2 Sat 48%.
Head ultrasound was obtained no evidence of intraventricular
hemorrhage
What is it?
1) Failure of diaphragmatic fusion
Foramen of Bochdalek (85-90%)
Foramen of Morgagni
What is it?
2) Herniation of abdominal contents into
thoracic cavity
3) Pulmonary hypoplasia
Incidence
~1:2500 live births
~1100 cases in the U.S. annually
$230M spent on hospitalization
Despite advances in care, survival
remains around ~65%
Diagnosis
Antenatal:
U/S at ~20 weeks gestation
~60% of CDH patients are diagnosed
antenatally
Proposed prenatal determinants of outcome:
polyhydramnios; intrathoracic stomach or liver;
abdominal circumference; lung-to-head ratio
Also search for associated malformations
Postnatal:
clinical signs of respiratory distress
XR: absent diaphragmatic outline, loops of bowel in
chest, tip of NG tube in thorax
Initial Management
Goal: oxygenate, avoid barotrauma
Intubate: conventional mechanical
ventilation
+/- Sedate
NGT for decompression
Pathophysiology
1) Pulmonary hypoplasia
“compression theory”:
- modeled in fetal lambs
- rationale for early surgery to remove “compressive” bowels
from thorax
“global embryopathy”:
- modeled in newborn rats
- rationale for new therapeutic ideas
2) Pulmonary hypertension
causes persistent fetal circulation
Medical Management
Goal: stabilize patient until definitive
surgical repair
Pulmonary vasodilators: inhaled nitric oxide
Inotropes, systemic vasoconstrictors:
dobutamine, dopamine, epinephrine
high frequency oscillatory ventilation
ECMO
Surfactant
Antenatal steroids?
Liquid ventilation?
ECMO
Surgical Management
typically a subcostal incision (thoracotomy
rarely considered)
gentle reduction of abdominal viscera
identification and excision of hernia sac
(found in 10%)
approximate diaphragmatic tissue with
sutures, Goretex, or muscle flaps
Developing Therapy
- Fetal surgery idea to remove herniated bowels early in
development stemmed from “Compression hypothesis”;
initial findings demonstrated no survival benefit.
- PLUG fetal surgery is an idea which makes use of the
observation that laryngeal atresia is associated with
enlarged hyperplastic lungs; Plug the Lung Until it Grows
- Growth factors injected during embryologic development
- Vitamin A important in lung development, maybe can
prevent CDH; prenatal treatment of Nitrofen rats with Vit A
showed decreased incidence of CDH at term.
Take home points
Defect, herniated bowel, and pulmonary
hypoplasia
Treat pulmonary hypoplasia/hypertension
medically until stabilized
Timing of surgical therapy based on optimization
of patient
Possible new therapies including prevention?
“An ounce of prevention is worth more
than a pound of cure.” - Benjamin
Franklin
References
[1] Downard CD, Wilson JM. Current therapy of infants with congenital
diaphragmatic hernia. Semin Neonatol. 2003 Jun;8(3):215-21.
[2] Smith NP, Jesudason EC, Losty PD. Congenital diaphragmatic hernia.
Paediatr Respir Rev. 2002 Dec;3(4):339-48.
[3] Jesudason EC. Challenging embryological theories on congenital
diaphragmatic hernia: future therapeutic implications for paediatric
surgery. Ann R Coll Surg Engl. 2002 Jul;84(4):252-9.
[4] O’Neill J, Grosfeld J, Fonkalsrud E. Chap 44. Congenital Diaphragmatic
Hernia. Principles of pediatric surgery, 2nd Ed. Mosby 2003.