improving the out come of diaphragmatic hernia

RE OPERATIVE IN DIAPHRAGMATIC HERNIA

Dr/Medhat M. IbrahimConsultant of pedia-surgery

“Good judgment comes from experience, and

often experience comes from poor judgment.”

OVERVIEW The complexity of patients born with

CDH creates a challenge to every surgeon

who must bring these infants to the operating

theater for the initial repair. In this instance, the operation is

relatively straight forward, but the physiology is treacherous.

Cont, Conversely, when situations arise

requiring a subsequent procedure, the physiology is often, but not always, more settled, but the procedure is usually much more difficult.

With increased survival has come increased morbidity and, not surprisingly, subsequent operations have become fairly common.

Cont, In one report, 42% of CDH survivors required

at least one additional operation. The need for reoperation is often predictable, as are the common indications.

First and foremost is a recurrence of the hernia.

Second feeding problem(gastro esophageal reflux (GER),

Then variable other causes as un descended testes, inguinal hernia, other.

Incidence of Reherniation

Re herniation after a CDH repair has varied from 2–22%.

But has been reported to be as high as 80% in a select group:

large defect, absent posterior portion of the diaphragm, Sever lung hypo- plasia that require ECMO ,long

mechanical ventilation. Patch graft repair, Neuorogenic defect associated with CDH as

phrenic nerve affection.

CONT, Also the method of initial reconstruction. Most important is the length of follow-up: Van Meurs et al., 40% of CDH survivors with a

patch repair eventually had a recurrence. Moss et al; reported that within 3 years of

initial repair, nearly 50% of patients who underwent a patch repair had developed a re-herniation.

Moss also noted that the majority of re-herniations were owing to the patch pulling away from the posterior thoracic wall

Presentation The majority present within the first 24

months of life. Moss and colleagues found a bimodal peak

incidence of recurrence. The first being between 1 and 3 months of age

and the second between 10 and 36 months. Saltzman et al. reported that the age at time

of recurrence ranged from 2 to 48 months, with the average being approximately 14 months

CONT, In fact, reherniation is often only

discovered on routine chest radiographs. For this recommend regular surveillance

chest radiographs is important as: Monthly for the first 6 months. 3months until the age of 24 months. Then at 30 and 36 months. Every 2–3 years until age 10.

Cont, in may experience the incidence of

recurrence drops precipitously after 6 months, so I do not obtain annual chest x-rays (CXR) for surveillance purposes alone unless there is clinical need after that time.

symptoms related to a reherniation Generally fall into two categories:1. pulmonary symptoms.2. gastrointestinal symptoms.

pulmonary symptomsI. Pulmonary symptoms are rare beyond

the neonatal period.II. Tachypnea, III. Persistent cough,IV. Development of aspiration pneumonia,

and/or recurrentV. Wheezing requiring increased use of

bronchodilators

Cont, Respiratory distress in an older child is

an ominous sign as tachypnea is usually a physiologic response to metabolic acidosis rather than pulmonary compromise.

Development of any of these symptoms should trigger a search for an occult reoccurrence.

The gastrointestinal symptoms Progressive oral aversion. New or increased feeding intolerance. Increased vomiting or worsening GER. Abdominal distension, or abdominal

pain. Although these symptoms are not

unique to reherniation,so I have differentiate between rehernation, adhesive intestinal obstruction, GER.

Diagnostic Tools The diagnosis of recurrent CDH should be

suspected based on history and physical exam, and can often be confirmed with a single chest radiograph.

Adjunctive radiological studies will be necessary to help better understand the anatomy as regards the location of reherniation and the amount of abdominal contents involved.

The studies of value upper gastrointestinal (UGI) with small

bowel follow through. contrast enema. With the advent of faster CT scans which

have eliminated the need for sedation, CT has become our preferred diagnostic tool.

In cases where reherniation is suspected on clinical grounds, but the chest film is equivocal

Upper gastrointestinal (UGI) with small bowel follow through.

Recurrent left CDH with bowel in chest. Note the pH probe.

Coronal CT reconstruction right CDH recurrence

The Surgical Approach patients can be divided into

symptomatic and asymptomatic groups. Symptomatic-------- urgent repair. Asymptomatic------- treated expectantly

for several months, or in some cases years, as long as they are carefully monitored.

I believe that all recurrences will eventually necessitate repair.

The justification for delaying repair in asymptomatic patients includes allowing time for improvement in:

Pulmonary nutritional parameters Tissue to be viable and tolerate repair Avoid bleeding and subsequent non required morbid

procedures. From a practical standpoint, repairing or

replacing a patch simply resets the clock until the next recurrence. So allowing the asymptomatic child to grow might allow for a more secure repair later and fewer repairs in total.

The choice of approach Theoretically, the repair can be performed

either via open or minimally invasive technique, but as a practical matter, the latter is probably only appropriate for the most minimal of defects.

The choice of approach may be influenced by other circumstances such as:

Fundoplication Gastrostomy tube will also be performed at the

time of the repair, An incisional hernia is present

The trans thoracic approach Favored by some It is more likely to provide a virgin operative

field in patients who initially underwent a trans abdominal repair.

Well not be reasonable in : child has evidence of pulmonary hypertension inadequate lung reserve Practically you cant repair the postero medial herniation

through it, also the retro peritoneal weakness cant be managed through.

If the patient need for other procedure as gastrostomy ,fundoplication, adhesolysis,

Trans abdominal approach which is often a bit more challenging and

time consuming. Allows us better visualization of the defect

itself, and the organs and structures that must be preserved.

It also provides ready access to perform a fundoplication and/or gastrostomy tube should one be needed.

The thoraco-scope It can be diagnostic Repair small postero lateral defect. Large rehernation is associated with

adhesion exposing the procedure to failure or end with morbidity.

So theoretically it is helpful ,practically it is too risk.

Repair Techniques plan the most appropriate repair technique. the mode of failure of the initial repair must be

ascertained. The location of failure is important, as it will dictate

subtle but important differences in timing and technique.

there are four primary modes of failure: failure of a primary repair failure of the medial aspect of the repair recurrence at the posterior-lateral margin

Development of a paraesophageal hernia which is not recurrence in all most the literature.

Anterior and lateral failures are rare probably because the anterior lip of

diaphragm seems to be the thickest muscle.

The liver act as a support foe the repair. The heart also from above. There is no real negative force at this

site as the maximum force loud come at the center of the diaphragm and posterolateral.

the cause of recurrence In the case of a failed primary repair, the cause of

recurrence is often a high-tension initial repair in which the sutures simply could not hold the tissue together.

In these cases, another primary repair is usually impossible and a new prosthetic patch should be placed.

A novel dome technique was described by Loff and coworkers in 2005.

A variety of novel approaches to repairing a recurrent hernia both with prosthetic patches and with muscle flaps have been described.

Holy Grail The “Holy Grail” of CDH repair is a patch that can

grow and remodel with the child. Recent large animal data suggest that CDH repair with autologous, engineered tendon patches is possible.

These grafts can be made available at birth, as they can be engineered in parallel to gestation, from cells normally present in, and harvested from, the amniotic fluid.

A proposed protocol for the first clinical trial of this novel therapeutic concept is currently under review by the Food and Drug Administration (FDA)

What we do? However, until pre-engineered bio

prosthetic patches become a clinical reality, we will

continue to rely on the synthetic devices currently available.