Farm Animal Surgery and Anaesthesia Flashcards
How do you prep a cow for the roll and toggle (Grymer-sterner) method to correct an LDA?
- Cast cow on RHS and roll to dorsal recumbency
- Clip from xiphoid to umbilicus
- Local anaesthetic blebs down midline - WORK QUICKLY
What is the roll and toggle technique for LDA correction? (explain landmarks etc)
- Identify ping in dorsal recumbency - DO NOT CONTINUE IF PING NOT IDENTIFIABLE
- Insert trocar 10-15cm caudal to xiphoid, 5-7cm to right of midline being careful to avoid the mammary vein
- Remove cannula and put 1st toggle suture through trocar lumen - ensure plastic toggle fully through and in abdomen
○ WORK QUICKLY as gas will escape - Remove trocar, move 10cm caudally and repeat whole process with 2nd suture
- Tie both sutures together allowing hands width between body wall and suture
Too tight - necrosis risk
What are the potential complications of the roll and toggle technique?
- Incorrect fixation (omentum, rumen, small intestines)
- Infection and fistulation
- Peritonitits
- Suture breakage (recurrence of DA)
- Abomasal obstruction
- Abomasal rupture
In which situation is it most suitable to use the roll and toggle method to correct an LDA?
Freely mobile abomasum with no adhesions
Describe the technique of how to carry out RHS (hannover) surgical correction of LDA and what are the “pexy” options available for this technique?
- Incision on right paralumbar fossa.
- Interal palpation of abdomen:
- Right arm cranial, left arm caudal to assess for liver and adhesions
- LEFT ARM reach caudally round rumen to locate abomasum with needle and tubing ( between rumen and body wall)
- Aided by pre-operative percussion and palpation of the left paralumba fossa
- Deflate abomsaum using needle and tubing - AVOID PERPENDICULAR PUNCTURE
- RIGHT ARM palm up reach cranioventrally (aim for left elbow) to grasp pylorus & pull up to incision
Pyloropexy or omentopexy
Describe how omentopexy is carried out
- Identify “Sow’s ear” (LANDMARK)
- Suture greater omentum to body wall at incision site & locate as close to pylorus as possible
- No more than 3-5cm away
- Wide vertical section of omentum including peritoneum
- 6-8cm
Describe how a pyloropexy is carried out
- Suture muscular part of pylorus to body wall at ventral aspect of incision site
- Locate sutures ~5cm cranial to pylorus to avoid stenosis and DO NOT enter pyloric lumen
- Ensure tight adherence
- +/- omentopexy
What are the possible complications of the right hand side surgical approach?
- Difficulty finding landmarks
- Difficulty moving abomasum
- Peritonitis
- Recurrence
- Omentopexy performed too far from pylorus
- Omentopexy breakdown - Pyloric stenosis
What are the advantages of the right hand side surrgical approach to LDA?
- Able to feel RHS GI organs
- Can visualise abomasum when stitching in
- Abomasum put back in right place
- Can turn into bilateral if see adhesions
- Can perform omentopexy
- Requires no assistant
- Prepare you for RDA and Caecal torsion
Describe the technique of how to carry out LHS (Utrecht) surgical correction of LDA and what are the “pexy” options available for this technique?
- Incision: 10-15cm close to last rib + ventral/ on left paralumbar fossa and abomasal fixation on ventral abdomen (caudally to the xyphoid process) = not co-located.
- Deflate abomasum: insert suture through greater omentum and abomasal wall
- Fixation point identified indirectly by internal palpation.
- Push abomasum ventrally, curved needle protected using palm of hand moved under rumen until fixation point reached and needle passed through ventral body wall to assist with reduction
- Repeat ~5cm caudal to 1st suture
- Identification of fixation point externally once in situ, while repetitively pressing the area with fingers to look for signs of advancing needle.
- Active reduction by pushing abomasum to ventral body wall whilst assistant ties 2 suture ends
Pexy: abomasopexy
What are the possible complications of the left hand side surgical approach?
- Peritonitis
- Ventral fistulation
- Milk vein +/- tributaries damage
- Failure to fix abomasum
What is the success rate for the LHS surgical approach?
88-93%
Describe the technique of how to carry out bilateral surgical correction of LDA
- The abdominal access incision and abomasal fixation are co-located on the right paralumbar fossa.
- The reduction of the displacement takes place by the surgeon on the left paralumbar fossa gently handling the abomasum and passing it underneath the rumen to the surgeon on the right paralumbar fossa.
- The identification of the displaced abomasum during the “passing over” phase (with or without sutures attached to its greater curvature) is done solely by palpation.
- The reduction of the displacement is carried out by applying gentle force on the displaced abomasum, until repositioned.
The deflation of the organ is passively achieved, once the abomasum is returned to the right.
Describe the technique of how to carry out right paramedian surgical correction of LDA and what are the “pexy” options available for this technique?
- Dorsal recumbency (xylazine GA)
- Incision on ventral abdomen caudally to the xyphoid process and right of midline (rectus abdominus)
- Reduce abomasal displacement by applying mild pressure on the abomasum by hand, until its return to the fixation area.
- Deflation of the organ is passive once it returns to its normal position, or actively by manipulation, or in severely inflated cases by paracentesis with a 14G needle.
Pexy: abomasopexy
How is abomasopexy carried out (for right paramedian surgical approach?
- Fixation of the fundus co-located with the incision
- Serosal surface pexy: 10-12cm long
- Fixation 2-4cm right of insertion of greater omentum
- Suture to internal rectus sheath + peritoneum
- Nylon continuous pattern
- Start caudal –> cranial
- Include abomasal serosa + muscularis layer
- DO NOT penetrate abomasal lumen
- Ensure correct closure of external fascial layer (strength holding layer)
