Forestomach: Hardware Disease and Vagal Indigestion

What is another name for Hardware disease?

Traumatic reticulopericarditis

Hardware disease is what most producers mean when they say their cow is —-.

Vagal

Why are cows especially predisposed to Hardware disease rather than small ruminants?

Cattle are indiscriminate eaters, using their tongues in a sweeping motion, and therefore are more likely to pick up things like nails or wire.

True or False: Non-perforating objects are frequently found in the reticulorumen, and their presence without evidence of inflammation does not support a diagnosis of hardware, but the common risk factor of exposure to metallic objects does justify the routine administration of rumen magnets to cattle.

True!

What exactly is hardware disease?

Rumen puncture with sharp object and the resultant inflammatory response and clinical signs

Name at least TWO risk factors for hardware disease.

1. Late gestation (pressure on rumen and reticulum, driving hardware through rumen wall)

2. Calving/straining

What are the FOUR major fates of a nail/wire in hardware disease?

1. Attachment to a previously administered magnet with no clinical disease

2. Penetrate reticular wall without peritoneal entry

3. Perforate reticular wall and enter peritoneum

4. Perforate reticular wall and enter peritoneal/thoracic cavity (pericarditis/abscesses/vagal indigestion)

You are called out to look at a cow that has begin to show clinical signs within 24 hours. The cow has suddenly dropped her milk and shows complete anorexia. She shows significant pain with abducted limbs, slow gait, fever, and tachycardia/tachypnea. There is markedly absent or reduced rumen motility.

How would you classify this based off of your primary differential?

Acute localized reticuloperitonitis

How long does it take an uncomplicated case of hardware disease to resolve?

3-5 days

True or False: Chronic reticulopericarditis looks a bit different, often involving poor hair coat, weight loss, intermittent anorexia, change in manure, and rumen dysfunction with or without tympany.

True!

What unique development do cows gain during chronic reticuloperitonitis?

Vagal appearance and gaunt

What would you do if you caught a case of hardware disease involving the peritoneum early? (3)

Give it antibiotics, anti-inflammatories, and a magnet

What kinds of signs do cows that have generalized peritonitis begin to develop over time?

Sepsis/shock (complete GI stasis, increased vitals, reduced perfusion, scant manure, pain)

What is the most common cause of cranial abdominal pain in mature cattle?

TRP

Name the SIX features which indicate cranial abdominal pain in cattle.

1. Absent ventroflexion with wither pressure

2. Grunt with wither pressure

3. Grunt with dorsal pressure on xyphoid

4. Reluctance to move

5. Arched back when standing

6. Forelimbs held in abducted position

What shape is associated with abscesses and adhesions involved with vagal indigestion in cattle?

Papple

What kind of heart murmur should put TRP high on your differential list?

Washing machine murmur or can't hear the heart at all (washed out by fibrin deposited)

What would you expect to see on CBC/Fib/Chem with a TRP?

CBC: neutrophilia (go on an abscess hunt) with increased TP or globulins

Fibrinogen: hyperfibrinogenemia

Chem: hypochloremia, hypokalemia, metabolic alkalosis

What would you expect to see on an abdominocentesis with TRP? (3)

1. TNCC >6000 cells/ul

2. TP >3 g/dl

3. Neutrophils >40% (consistent with peritonitis)

Why is a quadrant approach to belly tap important in cows?

Very good at walling things off- ensure you get representative sample

What are the TWO most helpful ancillary tests in TRP?

What would you do if you were on farm and these were not available?

1. Reticular radiography

2. Abdominal ultrasound

Standing flank exploratory (diagnostic + therapeutic)

What is the major limitation to cranial abdomen radiographs for TRP?

Limited to referral institutions

What diagnostic for TRP allows visualization of abnormal motility due to adhesions, peri-reticular abscesses, and peritoneal/thoracic/pericardial effusions?

Ultrasound

What does fibrin look like on ultrasound?

Swiss cheese or moth-eaten

What part of the reticulum is best to be viewed for assessment of motility?

Cranial ventral reticulum sac

What should you do if you see free fluid when assessing the abdomen in suspect TRP?

Tap and submit for cytology

Name FIVE major treatments for TRP.

1. Magnet

2. Broad-spectrum antibiotics (anaerobic; beta-lactam and tetracycline)

3. NSAIDs

4. Fluid resuscitation

5. Rumenotomy to remove wire/nail; lance abscess

What kind of standing laparotomy is preferred for TRP?

Left

What should you do if you detect a large walled-off abscess in the reticulum?

Lance into the reticulum

True or False: When lancing an abscess, the blade should be tied to the surgeon's wrist in case they were to drop it or lose it.

True!

True or False: Draining abscesses carries the risk of cellulitis, reticular fistula, and dissemination of peritonitis.

True!

When in doubt, what should you give a cow to prevent TRP?

Give that heifer a magnet!

Name and describe the FOUR types of vagal indigestion.

Type I: failure of eructation; free gas bloat (choke, pharyngeal trauma)

Type II: failure of omasal transport (TRP/hardware; bailing twine)

Type III: failure of pyloric transport/pyloric outflow obstruction (LDA; abomasal impaction; lymphoma; TRP)

Type IV: late gestation/partial pyloric obstruction/generalized ileus (less well defined; systemic like peritonitis, enteritis, hypocalcemia)

Just read this and it'll help, okay?

Type I: can't get into rumenoreticulum

Type II: can't get OUT of rumenoreticulum

Type III: can't get out of OMASUM (papple appearance)

Type IV: catch-all; systemic

True or False: Initial descriptions of vagal indigestion pertained to studies wherein transection of the vagus nerve resulting in rumen dysfunction were observed. Unfortunately, many cases of vagal indigestion do not have demonstrable vagus nerve involvement at necropsy.

True!

Identify the shape of each cow according to the type of vagal indigestion.

Type I: apple on left flank

Type II: bilateral papple

Type III: bilateral papple

Type IV: poorly defined

What causes the left apple appearance in Type I vagal indigestion?

Ruminal tympany- can be life-threatening

What are FIVE major causes of Type I vagal indigestion?

1. Choke

2. Frothy bloats

3. Respiratory disease

4. Damage to rumen wall/cardia sensory innervation

5. Extra-luminal masses around esophagus (thymoma; papilloma; tracheobronchial lymph nodes)

Which vagal indigestion is commonly related to abscessation?

What unique rumen shape is this type classified by?

Type II

L shaped rumen

What is the classic example of a Type II vagal indigestion?

Hardware disease (TRP)

Note: TRP is also a differential for Type III, but is MAINLY associated with Type II

Name TWO other common causes of Type II vagal indigestion.

1. Foreign bodies (hay twine, etc.)

2. Masses (papilloma)

What type of vagal indigestion is often associated with post-op abomasal volvulus, where there is vagus nerve damage that is stretched beyond repair and creates a papple?

Type III

Name FIVE common causes of Type III vagal indigestions.

1. Hardware disease

2. Abomasal damage after abomasal volvulus

3. Lymphoma

4. Abomasal impactions

5. Iatrogenic- toggle sutures; inappropriate pyloropexy

What vagal indigestion is a catch-all for things downstream and often involves late pregnancy?

Type IV

Name THREE other common causes of Type IV vagal indigestion.

1. Partial pyloric outflow obstruction

2. Proximal intestinal obstruction

3. Ileus

Type IV vagal indigestion is essentially anything downstream of the —- that you can't put another name to.

Abomasum

What are the THREE major ways to differentiate a Type II and Type III vagal indigestion?

1. II has normal rumen Cl, III has increased rumen Cl (can't get out)

2. II has normal to mildly decreased serum Cl, III has normal to severely decreased serum Cl

3. II has normal to mildly increased serum bicarb, III has normal to severely increased serum bicarb

Identify the location of abomasal distention in the types of vagal indigestion.

I: dorsal left

II: dorsal left, ventral right

III: dorsal left, ventral right

IV: dorsal left, ventral right

Identify what the rumen contents are in the types of vagal indigestion.

I: gas

II: fluid

III: fluid

IV: fluid

Identify what the rumen chloride is in the types of vagal indigestion.

I: normal

II: normal

III: increased

IV: normal to increased

Identify what the serum chloride is in the types of vagal indigestion.

I: normal to mildly decreased

II: normal to mildly decreased

III: moderate to severely decreased

IV: mild to moderately decreased

Identify what the serum bicarbonate is in the types of vagal indigestion.

I: normal to mildly increased

II: normal to mildly increased

III: moderate to severely increased

IV: mild to moderately increased

True or False: All hardware cows present as papple in shape (all hardware cows present as vagal indigestion).

False!

What THREE major ways would you conservatively manage an acute hardware case?

1. Magnet

2. NSAID

3. Antibiotics