Abomasum & Caecum Surgery PDF - 2021

Disease of the Abomasum. Robert Smith & Dai Grove-White Learning objectives • Describe the main surgical conditions of the gastrointestinal tract. • describe the aetiology of these conditions and their association with nutrition • Give an overview on surgical treatment of these conditions • Dila...

Disease of the Abomasum. Robert Smith & Dai Grove-White Learning objectives • Describe the main surgical conditions of the gastrointestinal tract. • describe the aetiology of these conditions and their association with nutrition • Give an overview on surgical treatment of these conditions • Dilation & displacement – Left sided displacement LDA – Right sided dilation and displacement • Abomasal ulcers • Geo-sedimentum abomasi (sand!) Epidemiology and aetiology • Dairy animals • Associated with high yield and concentrate feeding • Primary event is abomasal atony – Excessive VFA in abomasum – Inflammatory cytokines inhibit motility “Risk factors” • Usually seen in early lactation • Traditionally in housed but also seen at grass • “imbalance of fibre and concentrate” • • • • • – SARA Associated with ketosis and FMS Hypocalcaemia (clinical & sub-clinical) Concurrent inflammatory disease Cow comfort, lameness etc etc i.e. Anything that reduces DMI Investigation – where to look • Nutrition – Lactating diet – Dry cow feeding • Housing and comfort – lying time • Concurrent disease e.g. endometritis, mastitis – “Ping” cows that have endometritis and not reached expected yield at post calving checks Left displaced Abomasum • Most common abomasal disorder • “twisted stomach” • Target incidence ? – 0% – May accept 1-2% per annum – calculate cases/population at risk for given time period – can be dramatic “outbreak”! Published meta-analysis of studies using monensin in diets suggest odds ratio of 0.75 for ketosis and 0.75 for LDA in treated vs control cows (reduced by 25%) Clinical signs • Reduced milk yield (not as marked or sudden as a “wire” – insidious • Not reaching expected yield – parlour monitoring • Ketosis • Selective appetite – prefers fibre • Usually 0 – 4 weeks post calving • DO FULL CLINICAL EXAM ALWAYS Differential diagnosis 1. 2. 3. • • Vagal indigestion Peritonitis Gas in rumen (starved cattle /bloat) “Swingers” (transport) *May get LDA + another condition • Characteristic sounds and “ping”. Abomasal sounds • Spontaneous – tinkling & gurgling – (gently shake left flank with knee) • Ping – tap or flick rib hard – resonant ping – Indicates gas fluid interface – Map out area of “pings” • Absence of rumen sounds over displaced abomasum • Fat cows – no ping What happens Abomasum is fixed by: a) Omasum b) Duodenum c) Omentum Middle portion able to travel.   As rumino-reticulum contracts. Abomasum buoyed by gas works its way to left side. Rumen Abomasum Abomasu m Rumen Rolling 1. Cast - right lateral recumbency - then roll to dorsal - then roll over to left lateral - ping to see if moved – can repeat 2. Good quality roughage. Disadvantages 1. Least successful. 2. Ulcer rupture Advantages 1. Cheap. 2. Non invasive. 3. Concurrent disease. Toggling • No sedation Lft Toggling Place sutures where abomasum naturally lies. • Clip up before casting. • Avoid getting you head kicked in! • Avoid major abdominal blood vessels – mark with pen? • Ample labour Lft 2. Cast. 3. Maintain in dorsal. 4. Auscultate. 5. Caudal Toggle position = 15cm behind xyphoid 5 cm to Right Knee in abdomen to push abomasum forward 6. Push trochar firmly into abomasum Caudal toggle placed. Clamp on 7. Cranial suture placed (10 cm cranial to first suture) let gas escape. Knee in abdomen to push abomasum forward & expel gas 8. Tie Loose tie – 10-12 cm 8. Roll over. Advantages: 1. Cheap 2. Minimally invasive. 3. Relatively straight forward. 4. Quick. Disadvantages: 1. Going blind. 2. Do not see if Abomasum has ulcers/adhesions etc 3. Fistula formation. 4. Risk of getting kicked. Surgical methods. • • • • L & R sided approach – 2 operators L side (Utrecht) R side R paramedian approach – cow is cast Left to right / Bilateral flank 1. Para-vertebral. 2. Incision – 5cm caudal to last rib. Lft Rt 3. Both slide hand down wall of abdomen and shake hands. 4. Decompress abomasum. Manual / needle on flutter valve tube 5. Push abomasum to midline 6. Pull up to R. incision 7. Omentopexy. Right side. • • • •  Identify the pylorus – “sows ear” Pylorus palpated – “sausage” Omentopexy using omentum near pylorus Sows ear / sausage. Stitch the omentum by pylorus into wound closure. Right side omentopexy. • R flank incision • Put hand over rumen in backwards direction and feel top of abomasum on L side (14g needle on tubing to release most of gas) – flutter valve tube – Needle without cover so do not from cover or needle into abdomen • Withdraw arm Right side omentopexy. • Put arm (R?) in abdomen- follow R body wall down and under to L side • Identify abomasum (slight gas still in it) • Grasp abomasum/omentum securely • Firmly sweep down and pull to incision • Identify “sows ear” & pylorus • Omentopexy as described earlier L. Side omentopexy/abomasopexy (Utrecht method) • L side incision • Grasp greater curvature of abomasum or omentum • Weave suture through omentum or abomasum – leave 2 long ends (3 ft) • Decompress abomasum with 14G needle and tube • Attach needle to first thread (cranial) • Take down along body wall to R. ventral midline site (assistant guides from outside with forceps) – 4” caudal to xyphoid, slightly right – Avoid milk vein and other veins • Penetrate body wall with needle – unthread needle • Repeat with caudal suture (4” caudal) • Reposition abomasum down onto ventral abdominal as assistant “takes in” sutures • Tie sutures tight – make sure no guts (small intestine?) trapped between abomasum and body wall Use sheep prolapse needle “Buhner needle” Use nylon suture (thick, braided) or nylon tape Ventral abdominal paramedian: 1. Sedation / full GA. 2. Dorsal. 3. Line block. 4. Incise where abomasum normally lies. 5. Locate abomasum- should have returned. 6. Using cat gut, 4-6 mattress sutures through abomasum wall, peritoneum and abdominal wall. 7. Suture up. Post operative care. • Antibiosis ? - Pen/Strep, Oxytetracycline • Treat underlying conditions – Ketosis – propylene glycol – Endometritis etc (or treat pre-surgery?) • High fibre diet Which method ? • • • • • Toggle – cheap & quick Both sides –technically easier – 2 vets Utrecht – anatomically correct R. sided – technically harder ? Paramedian – anatomically correct but GA. Can see ulcers etc • Whatever the practice already does initially • Get good at it, then investigate alternatives? Right displaced abomasum Etiology: • Not fully understood. • Similar to LDA but less common. • Progression – Dilation & distension – Displacement – Torsion Pathogenesis Dilatation and displacement: • Atony / distension/ displacement. • Caudally on right side. • Dilatation phase may last few days. Metabolic sequelae of dilatation • Pooling of H+ and Cl- in abomasum • (upper intestinal obstruction) – Metabolic alkalosis – Hypochloraemia • 35 – 50 litres in abomasum • Dehydration • Increased luminal pressure causes mucosal damage. Volvulus phase: Torsion viewed from right side. Ischaemic necrosis Vertical plane around horizontal axis Why don’t LDA torse? Metabolic sequelae of displacement & torsion. • • • • Mucosal damage Cytokine release & endotoxaemia Metabolic acidosis Severe dehydration Dilatation and displacement phase. 1. 2. 3. 4. 5. 6. 7. 8. 9. Inappetent / depressed. Reduced faeces. Dehydrated. Tachycardia. Pale MM and dry. Doughy rumen – total outflow obstruction Reduced rumen turnover. Ping (middle to upper 1/3rd right side of abdomen) Tense viscus felt cranially per rectum. Torsion • Much sicker • Severe dehydration Differential diagnosis: 1. 2. 3. 4. Abomasal impaction. Caecal torsion. Traumatic reticulitis. Intestinal obstrucion. Treatment • Dilatation/displacement – Medical • Ca 40% • Metoclopramide – not authorised in cattle – no MRL • Buscopan (hyoscine also called scopolamine butylbromide) – not authorised in milking cattle – 2 day meat withhold for calves – EMEA opinion that does not need MLR – use under cascade? • Fluids – Surgical – drain & replace • Torsion – Slaughter – Surgery Surgery 1. Purse string suture Give fluids pre-operative • Hypertonic saline -5 litres 2. Tube. • Balanced fluids during surgery 3. Drain 4. Leave some fluid as indicator. • • • • Rotate abomasum. Watch duodenum. Anchor pylorus. Stitch up. Post-operative care • • • • • • Fluid therapy 50 – 100 litres (Hartmanns like) NSAID Antibiosis Oral KCl (50g daily) Ca 40% Propylene glycol Prevention: 1. Better dry cow management. Caecal dilatation and volvulus History • • • • • • Dairy cow. 1st few months of lactation. Inappetent. Decreased milk yield. Ping in dorso-caudal right sublumbar fossa. Rectally: Distended, recognisable viscus into the pelvis. Etiology: • ? Excess carbs which are fermented in caecum. Increased VFA, reduced pH and Caecal atony. Accumulation of ingesta and gas. Pathogenesis: • Similar to abomasal displacement. – Atony – Dilatation – Torsion Volvulus - Blind end is rotated cranially. - Body is distended. Torsion - Can occur with volvulus. - Twists longitudinally. Clinical findings Dilatation. 1. 2. 3. 4. 5. • Anorexia Mild abdominal discomfort. Reduced milk yield. Reduced faeces. Ping (right sublumbar fossa) May be incidental finding. Volvulus • 1. 2. 3. As above and: Dehydration. Tachycardia. Abdominal pain. Examination per rectum: • Distension: Long cylindrical, movable organ. Blind end points to pelvic cavity. • Volvulus: Points cranial and lateral or medial. Treatment: • Depends on severity. Medically. 1. Good quality hay 2. TLC 3. Monitoring hydration and heart rate Surgery: Determine if torsion. Caecotomy Purse string suture, Small incision, Milk caecal contents out. Once deflated, correct torsion and suture up. Post operatively. • Antibiotics etc. • Feed long fibre. • TLC • Prognosis is good. • Recurrence rate:11 – 13% in 1st week. 25% long term To summarise: • Simple dilatation • Volvulus • Twist - Not serious. - Observe. - Serious. - Surgery asap. - Necrosis of caecum. - Occurs with volvulus. - Surgery asap. Abomasal ulcers Summary: • • • • Mature cattle. Acute abomasal haemorrhage Melena Perforation acute local peritonitis. acute diffuse peritonitis. Etiology Primary: ? Secondary: To other diseases i.e. BVD. Multiple NSAIDS? Often incidental finding at slaughter. Causes Lactating dairy cows: Early lactation: a. Stress of lactation. grain. b. High levels of c. Increased incidence at grass???? Mature bulls and feed lot cattle: • Stressful events a. Transport b. Surgery. c. Fractures. Handfed calves: Common at weaning. Secondary cases: • LDA • RDA • Vagal indigestion. Pathogenesis Injury to gastric mucosa Diffusion of H+ ions into tissue. Damage Type 1. • Non perforating. • Minimal amounts of intra luminal haemorrhage. Type 2. • Major blood vessel perforates. • Severe blood loss. • Melena Type 3. • Perforating ulcer. • Acute, local peritonitis. • Peritonitis localised by greater omentum. Type 4. • Perforating ulcer. • Diffuse peritonitis. • In cattle • In calves - Fundic ulceration. - Pyloric ulceration Clinical findings: 1. 2. 3. 4. 5. Abdominal pain. Melena Pale MM. Sudden onset anorexia Tachycardia • Varying degrees. Perforation • Hypovolaemia. • Unable to stand. Treatment • Generally conservatively. Antacids: • 1st line. Magnesium oxide oral 800g /450kg daily Aluminium hydroxide oral 40g twice daily Blood transfusion / fluids. Haematocrit < 12%. 20ml / kg body weight. Shock fluids 10ml / kg / hr. Surgical excision Mid line. Either excise or over sew. Cost effective??? • Do not give NSAIDs or steroids. Oesophageal obstruction 87 Signs • • • • Inability to swallow. Regurgitation of feed and H2O Drooling. Bloat. 88 Etiology Intra luminal • • • • Potatoes / Turnips Placenta! Prevent by cutting them up before feeding Reduce competition, increased feed barrier space Extra luminal • Pressure by surrounding organs – Mediastinal abscesses. – Tuberculous Lymph Nodes 89 Clinical Signs • Cervical oesophagus above larynx. • At base of heart / cardia. 1. 2. 3. 4. Stop eating. Anxiety / restlessness. Salivation. Bloat 90 Treatment: • • 1. 2. 3. 4. Conservative approach. Many self resolve. Starve and observe. Sedate Buscopan Flunixin. 91 Manual removal: • Gag and pass hand to back of pharynx. • Assistant push FB up. – Probang with cutting loop on inside. 92 Cardia; • Push into rumen with probang. • Care – Strictures / diverticula. 93 • If unsuccessful: 1. 2. 3. 4. Trocharise rumen to relieve bloat. Feed via rumen. Wait till obstruction passes. Warn owner of possible oesophageal damage/necrosis 94 • Any different experiences?