Page 227 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery

• Closure of the hiatus: The oesophageal hiatus cannot surgical prudence dictates that the simplest surgery that
be closed completely, because the oesophagus still results in successful resolution of the condition represents
VetBooks.ir placed ventral to the oesophagus will have the effect of to come from a combination of techniques, rather than any
the most appropriate choice. The best success rates seem
needs to traverse the diaphragm (Figure 17.9). Sutures
moving the oesophagus to a more dorsal position,
single procedure.
which has been suggested by White (1993) or dorsal to
In attempting to evaluate the evidence for a particular
the oesophagus in the crural muscle, to preserve a method of surgical management, a number of problems
more normal position of the hiatus. Previous reports are identified:
have suggested closing the hiatus to a diameter of
1.5–2 cm, or the width of one or two fingers placed • Relatively few cases, with fewer large studies, are
alongside the oesophagus at the hiatus (Ellison et al., reported
1987; Miles et al., 1988). Care is taken to avoid the • The indications for surgery are not always clearly
dorsal and ventral branches of the vagus nerves and defined
the oesophageal blood vessels. • A consistent surgical technique or combination is not
• Fixation of the herniated organs: The abdominal always applied to all animals in a report
oesophagus is fixed in position by oesophagopexy. • More than one surgical technique is usually applied per
Simple interrupted sutures are placed to anchor the operative episode
oesophagus to the perimeter of the oesophageal • The endpoint of hiatal plication is subjective
hiatus. The fundus of the stomach is fixed in position • Some animals with an acquired hernia have had
with a left-sided gastropexy. Gastropexy not only surgery performed to correct the underlying cause as
physically prevents the stomach from being displaced well as the hernia, with success claimed for surgical
cranially, but it also increases the caudal oesophageal management of the hernia (Ellison et al., 1987)
barrier pressure, possibly by increasing longitudinal • Some asymptomatic animals have had surgery
stretch in the distal oesophagus, which causes reflex performed, with success claimed for surgical
contraction and reduction in lumen diameter, thus management of the hernia (Bright et al., 1990)
preventing gastro-oesophageal reflux. Stretching of the • Spontaneous remission of clinical and radiographic
diaphragmatic crura by gastropexy may also result in signs of hiatal herniation are reported in some young
an increase in muscle tone at the hiatus. dogs (Stickle et al., 1992)
• The definition of ‘successful’ surgical treatment varies
from lack of clinical signs to lack of imaging findings
• There is a relatively short period of follow-up in some
reports.
However, the following points can be made:

• Combinations of techniques seem to be more
efficacious than single techniques. This is evidenced
by the high rate of surgical failure when only one
technique is performed (van Sluijs and Happe, 1985;
Prymak et al., 1989; Bright et al., 1990) and the failure
of the entire procedure if one technique fails
• Plication of the hiatus and pexy of abdominal organs
are the mainstays of surgery
• Fundoplication techniques have a low rate of success
and high rate of morbidity.

Hiatal hernia: closure of the oesophageal hiatus. Sutures have Postoperative care and complications: Medical therapy
17.9 been placed in the diaphragmatic crura dorsal to the for gastro-oesophageal reflux should be continued during
oesophagus, to maintain its position. the immediate postoperative period. Feeding little and
often with a low-fat, highly digestible diet may also reduce
gastro-oesophageal reflux. Postoperative radiographs and
Similar decision-making lies behind the choice of fluoroscopy should confirm the resolution of the oesopha-
gastropexy technique for hiatal hernia to that employed for geal dilatation, the normal position of the stomach, lack
gastric dilatation–volvulus, and incisional gastropexy or of gastro-oesophageal reflux and improvement in oesoph-
tube gastrostomy may be selected. However, tube gastro - ageal motility.
stomy is recommended for the following reasons: Potential complications include: dehiscence of the
repair and recurrence of herniation; gastro-oesophageal
• It is simple and quick to perform reflux; oesophageal obstruction; pneumothorax; and aspi-
• It allows deflation of the stomach if gastric tympany ration pneumonia. Aspiration pneumonia and massive
occurs herniation with gastric tympany are the most common
• It bypasses the oesophagus, thus reducing causes of perioperative mortality (Callan et al., 1993).
regurgitation Dehiscence is usually the result of poor surgical tech-
• It allows feeding of the anorexic patient. nique. This is generally due to poor surgical access, result-
ing in inadequate suture placement. Surgical failure has
Choice of procedure: With such an uncommon condition, it been attributed to a shortened oesophagus and stricture
is difficult to compare the results of the various studies in one case (Bright et al., 1990). Gastro-oesophageal reflux
directly (Prymak et al., 1989; Bright et al., 1990; Callan et al., may continue if the hernia has not been adequately
1993; White, 1993; Lorinson and Bright, 1998). How ever, reduced, whereas oesophageal obstruction may result if

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