Term 5 DMN Week 12

A venous blood gas of a cow with a DA would show.

Hypochloremia, hypokalemia

A venous blood gas of a cow with a DA would show a pH of

7.45

What are the 3 methods of flank anesthesia in cattle

Paravertebral

Inverted L

Line

What are pros and cons of line block

Pro: easy and fast don’t need to find anatomy

Con: doesn’t block large area or go as deep, local anesthetic in incision → vasoconstriction micro hematomas delays healing

What are pros and cons of inverted L block

Pros: anesthetic away from incision line, blocks wide area

Con: larger anesthetic needed, more pokes, more anatomical knowledge

What are pros and cons of paraverterbal pros

Pros: deep anesthesia, larger area, less anesthetic needed, less pokes, not near incision

Cons: need anatomical knowledge, if you block L3 the cow could go down

What are risks factors for displaced abomasum in a cow

Mastitis

Abomasal ulcer

Ketosis

Stress

Hardware dz

Milk fever

Low roughage content of feed

Holstein cow

Change of ration

Estrus

RFM

Recently calved

Do LDA or RDA happen more frequently

90% LDA

10% RDA/RTA

Which cattle are predisposed to displaced abomasum

Guernsey (channel breeds), HF, Ayrshire breeds

Large abdominal cavity

Springtime in NA because grass quickly goes through GI and causes diarrhea

Why do cattle in the peripartum period have a chance of DA

Changes in abdominal topography (suddenly there is a lot of room)

What diet predisposes cattle to DA

High grain/low roughage

What are secondary dz associated with DA

Hypocalcemia (1st month of lactation)

Mastitis

Metritis

Retained placenta

Ketosis

Fatty liver

What is the normal pH of the blood in cattle

7.35

What are CS of LDA and RDA

TPR WNL or slight tachycardia

Reduced milk production

Anorexia

Left caudal rib sprung

Weight loss

Reduced fecal output

Chronic dull gaunt appearance and secondary ketosis

How can you dx LDA

Ping on auscultation

Liptak test: pH <4.5

Rectal exam

US

What are CS of RTA or RVA

Colic

Hypochloremia and hypokalemia

Metabolic alkalosis

How can you dx RDA

Ping on R 9-10 rib

Rectal exam

What are some ddx for a ping on the R side

DA

Gas in spiral colon

Cecal dilation/torsion

Physometra

Pneumorectum

SI obstruction/volvulus

Mesenteric root volvulus

Peritonitis

Pneumoperitoneum

What are some ddx for a ping on the L side

DA

Rumen tympany

Peritonitis

Pneumoperitoneum

What are some methods to treat a displaced abomasum

Roll and toggle or tact

Right sided omentopexy

Right sided pyloropexy

Left sided abomasopexy (long tack)

Right paramedian abomasopexy

Laproscopic abomasopexy

What is a conservative approach to tx a LDA

Roll and toggle

How is a cast and roll performed for LDA

Cast on right → roll over back clockwise

What is the problem with cast and roll

Recurrence is common

What is another term for abomasopexy

Blind tack/toggle

When is an abomasopexy/blind tack and toggle contraindicated

If respir compromise, no ping or concurrent abdominal dz

How is a abomasopexy/blind tack and toggle performed

Clip and prep cranioventral abdomen from umbilicus to xyphoid → identify milk well and vein with marker → cast and roll into dorsal recumbency → locate abomasum by ping right cranioventral abdomen → 1-2 sutures through skin and abomasum OR push cannula and trochar into abomasum through body wall and confirm by removing trochar and release of gas odor → place toggle pin through cannula → repeat if possible and check for pin → release gas → tie sutures together 1-2 fingers

What are pros and cons of the roll and toggle technique

Pros: avoid sx, quick to do, quicker recovery, cheap, enter milking herd sooner

Cons: can’t be certain enter the abomasum, may trap intestine between the toggles, risk of rolling cow, leakage of gut contents lead to peritonitis, abomasal rupture, fistula formation, detachment

How might you tell the trocar is in the abomasum

Check pH of gas (because specific…pH=3)

What are the surgical options for abomasal surgery

Abomasopexy for left displaced abomasum (LDA)

Abomasopexy for a right displaced or torsed abomasum (RDA/RTA)

Omentopexy or pyloropexy (LDA/RDA)

Paramedian LDA abomasopexy

What abomosal surgery can you perform on a standing left flank approach

Abomasopexy for left displaced abomasum (LDA)

What abomosal surgery can you perform on a standing right flank approach

Abomasopexy for a right displaced or torsed abomasum (RDA/RTA)

Omentopexy or pyloropexy (LDA/RDA)

What abomosal surgery can you perform on a cow in recumbency

Paramedian LDA abomasopexy

What are some pre-surgery tx that you can do for a cow before abomasal surgery

Analgesia best prior to sx- flunixin

Broad spec abx

Fluids IV

Sedation?

How do you perform a flank laparotomy

Incision middle of paralumbar fossa L or R 3-5cm distal to transverse process 20-25cm long through skin and subQ → exten vertical incision through external and internal abdominal oblique → elevate aponeurosis of transverse abdominus with forceps to make small incision and avoid inadvertent incision into rumen, use scissors or scalpel blad facing outwards to extend incision

What can you observe on the left flank laparotomy procedure

Rumen, reticulum

Spleen, left kidney, caudate lobe and gallbladder, diaphragm

Omental bursa contents

What can you observe on the right flank laparotomy procedure

Duodenum, pylorum, abomasum

SI, cecum, colon

Kidney, liver, gallbladder and diaphragm

What is the risk of the left flank approach when you are making the incision

Cutting into the rumen

How do you close a flank laparotomy

Transverse abdominis ± peritoneum: simple continuous 2/3 chromic catgut ventral to dorsal to retain intestines

Internal and external abdominal oblique: simple continuous 3 chromic catgut anchor to deeper suture to reduce dead space

Skin: ford interlocking heavy monofilament 2-3 interrupted at ventral aspect drainage if infected

How do you perform a left flank approach abomasopexy for an LDA

Long arms/2 people standing

Continuous interlocking suture in greater curvature → decompress gas and push abomasum ventrally → pass sutures through right paramedian body wall 10 cm to right of umbilicus and 10cm cranial of umbilicus

What are pros and cons of a left flank approach abomasopexy for an LDA

Pros: abomasum in natural position, less rummaging in cow, adhesions and ulceration can be directly visualized an treated, exploratory rumenotomy can be performed if indicated

Cons: need long arms, causes localized peritonitis, suture may detach and abomasum float back up, be wary not to puncture milk vein when passing needle through ventrum of cow

How do you perform a right flank approach abomasopexy for an LDA

Standing right flank approach → deflate abomasum in situ (LDA) → replace in correct position → retract (gently tug) omentum until pylorus visualized → anchor omentum (pigs ear) OR pylorus to internal muscle layer → routine closure of 2nd layer and skin

What are pros of a right flank approach

Better than ventral paramedian in severely compromised cow

Easier to remove fluid without contamination

Less risk to patient if standing

Only option if abomasal volvulus

No second person/long arm necessary (omentopexy)

Less of anchoring procedure performed blindly (abomasopexy)

Is an omentopexy or pyloropexy better

Pyloropexy is better because it is less likely to detach (the only problem is it may cause pyloric outflow obstruction)

Omentopexy not as good because it may detach especially in animals with fat mobilization

How do you perform a LDA abomasopexy using a ventral paramedian approach

Sedation and cast → dorsal recumbency reposition abomasum ± decompression → make incision 10cm right of umbilicus 10cm cranial of umbilicus, anchor greater curvature to peritoneum/internal rectus sheath → incorporate in 1st layer of closure with simple continuous → close external rectus sheath with horizontal mattress sutures → close skin with ford interlocking or simple interrupted sutures

What are pros and cons to a ventral paramedian approach

Pros: abomasum in natural position, instantaneous repositioning, able to examine abomasum for ulceration, strong adhesion formation

Cons: casting requires man-power, risk of regurg, cannot explore rest of abdomen, incisional infection

How can you perform a right flank approach omentopexy/pyloropexy for a RDA

Visualize the abomasum → decompress gas (if think torsion) → drain fluid place stomach tube through purse string suture → omentopex/pyloropexy as if doing an LDA → routine closure

What should be included in the post op management for DA

NSAIDs

± abx

Treat concomitant dz: dehydration, ketosis, metritis, mastitis

Neostigmine may stimulate intestinal motility but cannot be used in dairy cattle

Good quality roughage

What should be included in the post op management for abomasal volvulus

NSAIDs

Abx

Fluid tx: replace electrolyte def IV and oral

Transfaunation

Roughage

Neostigmine but not dairy

What are the indications for a rumenotomy

FB: TRP, obstruction

Rumen overload

Rumen impaction

What approach do you use for a rumenotomy

Standing sternal or R lat recumbent L lateral approach

How do you perform a rumenotomy

L flank laparotomy → anchor rumen to body wall (continuous inverting suture pattern, rumen board/ring) → incise rumen (explore rumen and reticulum, evacuate and replace contents) → close with continuous inverting pattern (2/3 chromic catgut 1 or 2 layers) → irrigate prior to removal of fixation sutures/device

What do you want to prevent in a rumenotomy

Prevent rumen contents from getting into the abdomen

What approach can you used for small intestinal conditions

Standing R flank approach

What are CS of SI conditions in cattle

Depressed

Drop in milk production

Caudal abdominal pain: stretching and treading

Increased HR

Decreased rumen activity

Anorexia

Reduced fecal output and melena

What are CS of SI conditions in calves

Similar signs to adults but hard to differentiate from enteritis

Decline more rapidly and bloat and colic

What can you see with ileus in cattle

Sequestration of fluid

Low bilateral distention

Fluid wave succussion

Hypochloremic metabolic alkalosis

What are causes to intussuscpetion in cattle

Viral enteritis

Diet alteration

Polyp/nodules

All causing hypermotility

What place does intussusception happen in cattle vs calves

Cattle: distal jejunum and ileum

Calves: throughout SI, less stoic than adults

How can you dx and tx SI volvulus in cattle

Dx: CS, US, rectal exam, exploratory laporotomy

Tx: stabilize first, right flank celiotomy, resection and anastomosis

Which approach can you use for cecal dilation and displacement

Standing right flank approach

What are causes for cecal dilation/torsion in cattle

Hypocalcemia

Elevated VFA production- inhibitory effect on motility

Risk factors- milking cows

What are CS of cecal dilation/torsion

Drop in milk yield

Reduced appetite

Discrete colic signs

Reduced fecal output

Distention of right paralumbar fossa

Examination of ping on percussion of right paralumbar fossa

How can you dx and tx cecal dilation/torsion

Dx: auscultation ping, rectal exam cecum palpable

Tx: right flank celiototmy, tymphlotomy

What are some complications that can be seen with cecal dilation/torsion

Septic peritonitis

Persistent motility disorder: recurrence 10-22%, cecal amputation/typhlectomy

What are some indications for typhlotomy

Cecal dilation

Cecal torsion

Cecal dislocation

How do you perform a typhlotomy

Standing right flank approach ventrocranial oriented incision parallel to internal abdominal oblique muscle → decompression of gas filled viscus → exteriorise cecum apex directed caudal in front of pelvis in normal position or torsion and apex directed cranially in dorsal or ventral retroflexion → isolate apex and incise most ventral location drain and milk out contents → close in 2 layers 2nd inverting cushing or lembert

What can cause atresia coli

Mid spiral colon most frequent early manual pregnancy testing <42d

Increased incidence in HF calves, alpacas and sheep

What are CS of atresia coli

Normal parameters for first 48hrs of life

Then appear bloated/abdominal distension

No fecal output

Distended loops of intestines (succussion, US)

What are sx options for atresia coli

Intestinal resection and anastomosis although more complex and has guarded to poor px

What animals are atresia ani seen in

beef > dairy

Sheep

What are CS of atresia ani

± lack of tail

Abnormal UGT: fistula between rectum and repro tract; rarely systemic symptoms if fistula present (female)

How do you tx atresia ani

Sx: electrolyte and fluid replacement, but consider px

Post op: maintain fluids and electrolytes, abx, resume oral feeding within hours

How do you perform sx for atresia ani

Local infiltration or caudal epidural when calve in lat or dorsal recumbency → circular cruciate or elliptical skin incision made over the bulging anal membrane or perineal site where the anus should normally be located → blunt dissection through subQ and perineal muscles → blind end or rectum pulled outward to skin edge and opening created to release accumulated meconium → cute edge of rectal mucosa stitched directly to perineal skin using simple interrupted non-absorable sutures to form permanent anal orifice

If rumen chloride is high where is the presumptive obstruction

Pylorus

What nerves are blocked for a distal paravertebral block

T13

L1

L2

Transverse processes of which vertebrae are used as landmarks for the distal paravertebral nerve

L1

L2

What is the first thing you see when entering via the R paralumbar fossa in a normal bovine

Cecum

What suture pattern and what direction is best used to close the transverse abdominis and peritoneum

Simple continuous dorsal to ventral

What suture pattern is best used for the skin

Ford interlocking

For what GI surgery is performing a recumbent laparotomy recommended in an adult cow?

SI strangulation because risk of going down is so high

What is the potential causes of adhesions in cattle

Abomasal ulcer

Generalized peritonitis

Reticular abscess (TPR)

Liver abscess

Acute pancreatitis is more common in which species while chronic is more common in which species

Acute- dogs

Chronic- cats

What are the autodigestion defenses in the pancreas

Zymogens are inactive and must be physically separated from lysosomes and activated in the SI

Pancreatic secretory trypsin inhibitor (trypsin activated in SI by enterokinase)

Plasma anti-trypsin alpha-macroglobulins

What happens in autodigestion failure aka pancreatitis

Activation of zymogens within the pancreas

Autodigestion

Local inflammation

Systemic inflammation → can lead to DIC, SIRS

What are CS of pancreatitis in dogs

Anorexia 91%

Vomiting 90%

Lethargy 79%

Diarrhea 33%

Icterus

Fever

Prayer position- abdominal pain

What are CS of pancreatitis in cats

Lethargy 100%

Anorexia 97%

Vomiting 35%

Diarrhea 15%

Dyspnea 20%

Icterus 20%

Fever

What is EPI

Exocrine pancreatic insufficiency caused by pancreas not secreting digestive enzymes into the SI leading to failure to break down fat, protein and carbs leaving food undigested in the intestines and osmotic diarrhea

What are CS of EPI in dogs

Weight loss

Diarrhea: steatorrhea, large volume, pale, malodorous

Polyphagia

What are CS of EPI in cats

Vomiting

Polyphagia

Weight loss

Compare SNAP vs spec PLI

SNAP: semi-quanitiative based on color intensity, can help rule out pancreatitis but must be confirmed

Spec: quantitative and gives an actual number and confirm pancreatitis

Which test is quantitative for for chronic pancreatitis in cats

Spec fPLI

What can cause icterus in pancreatitis in cats

Post hepatic icterus because common bile duct is blocked by the pancreatic duct being backed up

What can trigger pancreatitis in dogs

High fat meals

Different food than normal

Breeds: Yorkies, Schnauzers

Metabolic: obesity, diabetes, hypertriglyceridemia, Cushing’s medications

Vomiting

What can cause pancreatitis in cats

Total of partial obstruction pancreatic duct induced chronic changes to the pancreas

Association with pancreatitis, chronic inflammatory enteropathy and cholangitis

Hypoperfusion/thrombosis

What happens in triaditis

Pancreatitis, chronic inflammatory enteropathy and cholangitis because of the insertion of the common bile duct and major pancreatitis duct into the duodenal papilla together

What lab abnormalities can be see with pancreatitis

CBC- neutrophilia with L shift (not usually noted in cats)

Hypoalbuminemia- vasculitis, edema

Azotemia- pre-renal or renal

Elevated liver enzymes: T bili, GGT, ALP inflammatory/cholestatic

Hypocalcemia

High cholesterol, triglycerides

Hyper/hypoglycemia (Cats)

Hypokalemia (cats)

UA maybe ketones

What can you see on abdominal rads with pancreatitis

Decreased serosal detail “ground glass” wide gastroduodenal angle

Important to rule out other causes of vomiting

What can you see on abdominal US with pancreatitis

Hypoechoic pancreas

Surrounding mesentery hyperechoic

± common bile duct obstruction

More specific for pancreatitis in dogs than cats for acute rather then chronic

How can you dx pancreatitis

Biopsy is gold standard but often not perfomed

Lipase and amylase are secreted by other organs so not pancreas specific

Abd US useful but should not be the only diagnostic test

Pancreatic lipase immunoassay: SNAP/spec

C-reactive protein: not diagnostic alone but prognostic

What are other causes of positive PLI

Acute abdomen, hyperadrenocorticism, pancreatic neoplasia