Abdominal wall surgery Flashcards
Abdominal wall muscles. (4)
External abdominal oblique (cranioventral)
Internal abdominal oblique (caudoventral)
Transversus abdominalis (dorsovental)
Rectus abdominis (craniocaudal)
whats that tentacle thing
falciform ligament
Name the layers of the Ventral abdominal wall (from exterior towards interior) (6)
Skin
External lamina of rectus sheath
Abdominal rectus muscle
Internal lamina of rectus sheath
Transverse fascia
Peritoneum
Name the Lateral abdominal wall (from exterior towards interior): (8)
Skin
Cutaneous trunci muscle
Deep fascia
External abdominal oblique muscle
Internal abdominal oblique muscle
Transverse abdominal muscle
Transverse fascia
Peritoneum
red muscle?
External abdominal oblique muscle
red muscle?
Internal abdominal oblique muscle
red muscle?
Transverse abdominal muscle
red muscle?
Abdominal rectus muscle
name the glands pictured
cranial thoracic mammary glands and teats
caudal thoracic
cranial abdominal
caudal abdominal
inguinal
Of note in male anatomy and abdo surgery?
skirt around the penis if you need to extend your incision
the external pudendal is frequently incised and must be appropriately dealt with.
The Linea alba is
the fusion of aponeuroses of external and internal oblique abdominal muscles at the
median level of the ventral abdominal wall, between two rectus abdominis muscles.
The Linea alba is wider in the cranial part of the abdomen and narrower in the caudal part.
Natural openings in the abdominal wall. (3)
Femoral canals - separated from inguinal canal with inguinal ligament.
Inguinal canals – bilaterally symmetrical openings in the caudoventral abdomen.
Umbilicus – scar in the middle of the linea alba.
laparotomy vs coeliotomy
Strictly speaking, laparotomy refers to an abdominal incision through the flank.
Coeliotomy is the more correct term to refer to a midline approach; however, both terms have come to be used interchangeably.
Laparotomy incision options: (4)
Upper midline incision – extends from the xiphoid process to the umbilicus.
Lower midline incision – extends from umbilicus to the pubic symphysis area.
Paramedian incision
Paracostal incision, parallel to the last rib.
Ventral laparotomy in small animals:
Indications?
Anesthesia?
Site prep?
Equipment?
Indications: exploratory laparotomy, surgeries on abdominal organs.
Anesthesia: general anesthesia + regional and local.
Surgical site preparation: the hair is clipped from the xiphoid region to pubic bone. Thereafter, the surgical site
is prepared in compliance with general aseptic rules.
Equipment: general set of surgical instruments, retractors (ex. Balfour retractor).
weitlaner retractor
balfour retractor
lone star retractor
alexis retractor
Ventral laparotomy in small animals: The incision is made either..
And describe opening the abdomen.
in front of or behind the umbilicus, if
necessary – over the umbilicus.
After cutting through skin, subcutaneous tissue, and external lamina of the rectus sheath, the linea alba, becomes exposed.
Make a stab incision to the line alba with a scalpel.
A stab incision and letting air into the abdominal cavity allows the abdominal organs to “fall” dorsally, away from the ventral aspect of the abdominal wall.
Insert thumb forceps with the tips placed caudally to lift upward on the linea alba and make a cranial to caudal incision.
approach for abdominal exploration
Use a systematic approach for abdominal exploration.
Abdominal organs should be inspected by direct vision and palpation.
intestinal plication due to linear foreign body
Describe the Closure of the abdominal wall.
The first layer of simple continuous sutures is placed on the external lamina of rectus abdominis (resorbable mono- or multifilament). Whole layer of abdo wall is closed this way (pictured). Only if its very thick you can do like in the lower image, go through half. Tighten the abdo sutures very well!
The second layer of continuous sutures closes subcutaneous connective tissue (resorbable mono- or multifilament).
The skin is closed with intra–dermic continuous suture (resorbable monofilament) or simple interrupted suture (non-resorbable monofilament).
falciform ligament
If you remove it, you’ll encounter some big blood vessels you’ll need to ligate or otherwise close.
Describe Hernias in relation to surgeries.
True hernia vs false hernia etc.
= Protrusion of an internal organ through a defect in the wall of the anatomical cavity in which it normally lies.
A True hernia is the protrusion of abdominal contents through an existing, or potential, opening in the body wall
that has become pathologically enlarged or disrupted. True hernias are always located in a sac which is actually peritoneum.
A False hernia is the protrusion of abdominal contents through a rupture of body wall. False hernas do not have a sac.
Presents as subcutaneous “swelling”.
Abdominal wall hernias are
abnormal openings in the muscle wall of the abdominal cavity that allow the
protrusion of intra-abdominal fat or organs into the subcutaneous or intramuscular space.
Are Most often congenital.
Hernial ring is?
Hernial sac is?
Hernial contents?
Hernial ring is the actual defect in the abdominal wall.
Hernial sac (external and internal) surrounds the hernia contents.
Hernial contents are the organs or structures that are permitted to pass through the ring (commonly fat,
intestinal loop or omentum).
Describe Umbilical hernias
(hernia umbilicalis)
+ predisposed breeds?
Occur on the ventral abdominal midline through the umbilical ring.
Umbilical hernias form because the umbilical ring in the abdominal wall during fetal development does not either close up or gets ruptured during birth (traumatic).
Breed predisposition:
basenjis, Pekingese, pointers.
a birth defect where there is a hole in the abdominal (belly) wall beside the belly button.
Gastroschisis
(vs
An omphalocele is a birth defect in which an infant’s intestine or other abdominal organs are outside of the body because of a hole in the belly button (navel) area.)
Surgery of reducible small umbilical hernia.
In case of a small umbilical hernia that contains only fat, an incision is made directly over the hernia.
The internal hernial sac is inverted and the hernia ring is closed without necessarily debriding the edges of the ring. (depends on the hernia)
Simple interrupted suture pattern with synthetic monofilament absorbable or nonabsorbable.
Surgery of reducible large or inflamed umbilical hernia.
In case of a large or inflamed hernia, the incision is made around it. Thereafter, through the surgical wound, the internal hernia sac is separated.
It is necessary to expose 1–2 cm of hernia ring around abdominal wall.
The internal hernial sac is reduced into abdominal cavity. If you’re not able to reduce the hernial contents - its likely due to adhesions.
The edges of hernial orifice are joined with a SIMPLE interrupted suture.
After such surgery the internal hernial sac remains intact and abdominal cavity closed.
If abdominal muscles are weak or severely damaged, what should be done at closing?
Marlex or Prolene synthetic mesh is used for closing
In case of inguinal hernia, omentum, rarely, a loop of the small intestine, bladder, part of the large intestine or uterus protrude through from abdominal cavity into inguinal canal.
This type of hernia occurs in all animal species, although it is more frequent in
small dog breeds (Miniature Poodle,
Pomeranian Spitz, Chihuahua, Pekingese, American Cocker Spaniel, Cavalier King Charles Spaniel).
More common in females dogs actually. More commonly left sided in dogs.
This type of hernia rarely occurs in felines.
Obesity, chronic constipation, and gestation may contribute to hernia formation.
It may be congenital and inherited, or traumatic.
Inguinal hernia may be categorized as..?
direct and indirect.
In case of direct hernia, hernial contents (omentum or organs) protrude through inguinal canal NEAR vaginal process (tunica vaginalis) (more frequent in female animals).
In case of indirect hernia, hernial contents protrudes THROUGH vaginal process into vaginal cavity (in males) and may also form scrotal hernia.
The paired inguinal or vaginal canal is located in the rear part of ventral/ anterior abdominal wall.
What structures may pass through it?
Pubic artery, vein, and nerve, as well as, in male animals, spermatic cord (including blood vessels and nerves) and cremaster
muscle, and, in female animals, round ligament of uterus, go through this region.
Superficial inguinal ring is a
slit–like external entrance going posteriorly from the anterior part of the inguinal canal.
It is formed by the external abdominal oblique aponeurosis and inguinal arch.
Deep inguinal ring is the
internal entrance into inguinal
canal. It is formed by the caudal edge of internal abdominal oblique muscle, inguinal arch, and transverse fascia.
Describe Surgery of inguinal hernia.
Knowledge on topographic anatomy is essential!
an incision is made from above superficial inguinal ring till the internal hernial
sac.
The internal hernial sac is fixed using fingers and bluntly dissected along its whole length till hernial orifice.
Internal hernial sac is cut open and hernial contents is reduced back to the abdominal cavity.
An empty internal hernial sac is ligated in its neck, amputated and hernial orifice is closed with interrupted suture using synthetic slowly resorbable or non–resorbable suture material.
What to remember when closing an inguinal hernia?
&
The most important thing to remember about inguinal hernia surgery?
Always start suturing from cranial-caudal. And you must leave a slight opening in the inguinal canal due to the blood vessels that need to pass through it.
It is crucial to remember that the external pudendal artery, vein, and genitofemoral nerve are located in caudomedial part
of the inguinal canal.
Be careful when closing not to damage them. A severe hemorrhage may occur, if those are damaged. It is equally important not to press or ligate these blood vessels and the nerve.
Describe scrotal hernias.
In case of scrotal hernia, loops of small intestine protrude through the inguinal canal into scrotum, where they are
either located in the vaginal cavity (more frequently) or outside parietal lamina of tunica vaginalis.
It occurs in all species, although is most frequent in swine.
It is commonly congenital.
Scrotal hernia is usually reducible. irreducible scrotal hernias are rare, and squeezed hernias – very rare.
identify and describe
Scrotal hernia in canine/dogs:
Indirect inguinal hernias
Occur rarely
Young male animals
The surgery is performed promptly after diagnosis.
High risk of adhesions.
The surgery may be performed together with castration (recommended) or without it.
Scrotal hernia surgery in dogs.
The incision is made above the inguinal canal.
Hernial contents is reduced through inguinal canal into abdominal cavity (if necessary, internal hernial sac is opened).
The internal hernial sac (parietal lamina of tunica vaginalis) is narrowed in hernial neck area close to hernial orifice (inguinal canal) using mattress suture.
The cranial part of the inguinal canal is closed with slowly resorbable suture material.
Surgery of scrotal hernia combined with castration.
Internal hernial sac is opened, hernial contents is reduced through inguinal canal.
The testicle is massaged out through the scrotum. The ligament of epididymis is cut through, the blood vessels and
sperm duct are ligated and cut through.
The internal hernial sac is ligated in its neck area close to inguinal canal and removed.
The inguinal canal is closed with interrupted suture without pressing or ligating the blood vessels and the nerve.
Thereafter, the other testicle is removed.
