Editing Hiatal hernia


Herniation of elements of the abdominal cavity through the oesophageal hiatus

== '''Anatomy''' ==

* Phreno-oesophageal membrane     is responsible for maintaining the oesophagus in its position below the     diaphragm - a continuation of the endoabdominal peritoneum that reflects     onto the oesophagus at the hiatus
** Subject to wear and tear      with aging
** Plus repetitive stress of      swallowing, abdominal straining, vomiting
** Potentially also due to      tonic contraction of oesophageal longitudinal muscles in response to GORD

== '''Pathophysiology (para-oesophageal)''' ==

* Para-oesophageal hernias form     after two key events:
** Widening of the      diaphragmatic crura at the oesophageal hiatus
** Stretching of the      para-oesophageal membrane, as it balloons into the posterior mediastinum
* Viscera enter hernial sac     repeatedly, and eventually adhesions form
* Most commonly gastric fundus

== '''Types:''' ==

* The key differentiating     factor is the location of GOJ and fundus
* Type I - '''sliding''' (95%)
** Displacement of GOJ above      diaphragm into the posterior mediastinum
** Fundus below diaphragm (no      paraoesophageal hernia)
** Occurs because of laxity of      the phreno-oesophageal membrane
** Associated with trauma,      congenital, iatrogenic
** Often leads to GORD, with      larger hernias conveying a higher risk for pathological GORD
* '''Paraoesophageal''' - true hernia with a sac and     part of the fundus above the diaphragm
** Recognised complication of      surgical dissection of the hiatus
** II - defect in      phreno-oesophageal membrane - fundus is above but GOJ remains anchored in      the abdomen
** III - mixed - elements of I      and II - both GOJ and fundus herniate through hiatus
** IV - large defect in      phreno-oesophageal membrane - includes other organs in hernial sac, e.g.      colon, spleen, pancreas, or small bowel
**




== Natural history ==

* Increases in size over time
* 25% of sliding hiatus hernias     become a paraoesophageal hernia

== Clinical features ==
Type I

* Generally asymptomatic
* May have symptoms of GORD     (heartburn, regurgitation, dysphagia)

Type II, III, IV

* Mostly asymptomatic or vague,     intermittent symptoms
* More likely to see     obstructive symptoms - dysphagia, early satiety, post-prandial epigastric     pain
* Can also be associated with     typical GORD symptoms
* Complications
** Gastric volvulus
*** Risk is approximately 1%       per year
*** See separate topic
** Respiratory complications
*** Mass effect of hernia in       chest
*** Shortness of breath is       common
** Bleeding
*** Results from mucosal       ischaemia or mechanical ulceration of the gastric mucosa
*** Cameron's ulcer



== Diagnosis ==

* Barium swallow - sliding =     >2cm gap between B-ring and diaphragm
**
* Upper endoscopy - >2cm     between B ring and diaphragmatic impression

== Investigation pre-op: (these guidelines are American - unsure if applicable here) ==

* Acid exposure test to     document GORD
* Manometry (ensure dysmotility     isn't contributing to reflux)
* Barium swallow (look out for     short oesophagus)
* Gastroscopy (exclude     malignancy) - can be done at time of repair

Cameron's says pH testing and manometry aren't necessary in most patients

== Management ==

* Type I
** Asymptomatic - no      intervention
** Symptomatic - treat as for      GORD - ie medical management, then reflux control surgery, especially if      they had a good response to treatment.
* Paraoesophageal
** Asymptomatic - somewhat      controversial, but no intervention probably best
*** Large hernias should       probably be repaired in patients with low anaesthetic/operative risk, to       prevent volvulus/strangulation
** Symptomatic - repair      indicated electively
** Emergent repair indicated if      gastric volvulus, bleeding, perforation, obstruction, resp compromise      present



== Paraoesophageal hernia repair ==

* Can be done open, lap, or     transthoracic
* First, endoscopy
* Lap probably best first     option although never been compared directly

=== Indications: ===

* Patients with volume reflux
* Symptoms respond to PPI
* GORD with negative test for     oesophageal dysmotility
** Lithotomy, both arms at      90deg. Surgeon between legs.
** Nathanson retractor to pull      up left lobe of liver
** Divide lesser omentum to      expose the right hiatal liver
*** Be aware of hepatic branch       of vagus nerve and aberrant left hepatic artery
** Dissect hernial sac and      completely remove from mediastinum - circumferential dissection
** Mobilise oesophagus
** Tension-free repair of      hiatal defect, generally without mesh. Mostly interrupted sutures - maybe
** Perform complete Nissen      fundoplication
** Anterior gastropexy to      reduce risk of reherniation

=== Complications ===
** Intra-operative
*** Hepatic/splenic injury
*** Bleeding from short       gastrics
*** Perforation of oesophagus
*** Inability to reduce       oesophagus - happens with long-term GORD - scarred
*** Pneumothorax - common -       won't be any consequences, will disappear after laparoscopy
** Long-term
*** Dysphagia, gas bloat,       difficulty to belch
*** Vagotomy
** Dysphagia
*** Too tight wrap
*** Disruption of wrap
*** Sliding HH - stomach slides       up under wrap
*** Slipped fundoplication -       wrap falls down
*** Intra-thoracic migration

=== Post-op ===
** Antiemetics - don't want      vomiting
** Barium swallow D1 post op -      look for leak/recurrence, evaluate gastric emptying
** If swallow ok, start of      clear fluids
** Discharge after a couple of      days generally
** Start soft/puree diet D4,      then normal diet in four weeks. Avoid large meals early.
** Expect some degree of      dysphagia for 4 weeks or so.

=== Outcomes ===
** 90% have long-term symptoms      relief
** 40% have some degree of      radiographic recurrence

=== Controversies ===
** Open vs laparoscopic
*** Lap should now be standard       of care, even for massive and/or recurrent
*** If lap fails, left       thoracotomy would be best approach
** Also do antireflux?
*** Almost certainly yes
** Mesh?
*** Long-term risk of erosion       is unknown
*** Onlay biologic prosthetic       mesh if needed in preference to synthetic
** Ligation of short gastrics -      no evidence it improves wrap, but it does make it easier to flip fundus      over

[[Category:UGIS]]