19 Rumen Evaluation and Surgery Part 1

• Rumen Evaluation and Surgery is covered in VCS 878 by Miesner

Indications for Rumen Surgery

• Rumen surgery may be indicated to gain Access to the Rumen
• Some Access to Rumen indications include: Frothy bloat, Free gas bloat/Chronic re-occurring bloat, Ruminal foreign bodies (Hardware disease, other), Vagal indigestion, Grain overload, Toxin ingestion, Experimental/Research
• Rumen surgery can be useful for making a rumen donor (rumen canula)

Ultrasonography

• Ultrasound findings (Braun, 2003) can show inflammatory fibrinous changes and abscesses
• Magnets and other foreign bodies cannot be imaged with ultrasound

Measuring Fibrinogen

• Fibrinogen can be measured by heat precipitating from plasma and measuring the difference of TP between samples; normal is less than 500 grams.
• A "coffee cup" method involves using 130°F H₂O for 3 minutes.
• The difference between TP measurements estimates fibrinogen.
• For example, if the initial TP is 9.5 and post-heat treated TP is 8, then estimated fibrinogen is about 1.5 grams.

Radiography

• Radiography is a potential diagnostic tool.

5 y/o Gelbvieh Cow Case

• A 5 y/o Gelbvieh Cow, presents with a complaint of intestinal obstruction
• Exam findings include that the cow is Alert, has a Papple shape, Normal TPR
• In the case the cow has scant/no Feces in rectum and large rumen and the cow cannot decompress with Oral-rumen intubation
• Ultrasound and Bloodwork are part of the case's plan

Rumenotomy

• Part of the dorsal rumen sac is exteriorized through the laparotomy incision
• Starting at the dorsal aspect of the incision, the rumen is sutured to the skin in a Cushing-type pattern to form a seal
• Partial thickness bites should be taken through the rumen wall
• After seal is created between rumen and skin, the rumen is incised leaving approximately 3 cm at the dorsal and ventral part

Left Flank Laparotomy

• Anesthesia for left flank laparotomy can be standing procedure, using Local or regional anesthesia
• Local or regional anesthesia may include a Proximal / Distal Paravertebral nerve block, Inverted L-block, or Line block with 2% Lidocaine HCI
• A skin incision (~20cm dorsoventral) is made in the left paralumbar fossa
• The incision is made approximately 4 cm (hand width) caudal and parallel to the last rib
• Make the incision approximately 6 to 8 cm ventral to the transverse processes of the lumbar vertebrae
• Surgeons with short arms may require the incision to be more cranial and ventral for full reticular exploratory

Rumenotomy - Methods and Goals

• Rumenotomy methods include skin fixation techniques and rumen boards
• Rumenotomy goals include to avoid peritoneal contamination and to gain access to rumen

Skin Suturing Fixation

• The dorsal sac of rumen is exteriorized through left flank incision
• Rumen was sutured to skin using #2 silk in a continuous Connell pattern
• Suturing began midway down caudal part of incision and continued in a clockwise direction
• Suture pulled tight to invert skin edges under rumen for good seal

Rumenotomy Board

• For the rumenotomy board method, the incision should be made in a fold of rumen wall starting ventrally, placing hooks as the incision is made

Other Rumenotomy Variations

• Other methods include Rumen Skin Clamp Fixation, Stay Suture Rumenotomy, Weingarth's Ring Rumenotomy

Rumen Skin Clamp Fixation

• Rumen is exteriorized through incision and firmly anchored to skin dorsally and ventrally by towel clamps
• Rumen was opened and towel clamps placed cranially and caudally
• Additional clamps placed between these clamps
• The rumen edges were made to overlap the skin edges by 2-3 cm

Stay Suture Rumenotomy

• Rumen is exteriorized through incision
• Rumen wall anchored to incision dorsally, ventrally, cranially, and caudally by 4 sutures using #2 nylon
• Rumen exploratory is performed using rumen shroud

Weingarth's Ring Rumenotomy

• Weingarth's frame was fixed to dorsal commissure of the incision
• As rumen wall was incised, hooks placed into cut edge of rumen wall and hooked to frame

Rumen Exploratory

• It is difficult to explore cattle with a full rumen
• A 24 hour fast prior to rumenotomy can help as well as evacuating part of the rumen mat
• The dorsal and ventral rumen sacs should be explored
• A Rumen Exploratory can reveal Grain overload, Frothy / Free gas bloat, Sand accumulation, Rumenal foreign bodies, Rumenitis

Reticular Exploration

• Reticular Exploration can be difficult for surgeons with short arms
• Placement of body wall incision is critical and Rumen board techniques can limit the reach
• A main indication for Reticular Exploration is Hardware disease
• Check for adhesions of reticulum to body wall as well as palpate for abscesses
• Abscesses can be lanced into the reticulum and Ultrasound can be helpful for the exploration
• Palpate reticuloomasal orifice for Obstructing foreign bodies
• A magnet should be placed on the way out

Rumenotomy Closure

• A 2 layer inverting closure should be completed with absorbable suture
• Copious lavage should be done prior to releasing the rumen from skin
• Perform a routine abdominal wall closure

Laparotomy Closure

• A 2 layer muscle closure should be performed using #3 chromic gut for Peritoneum & Transverse abdominus and Internal & External abdominal oblique muscles
• Skin is routinely closed with Ford Interlocking pattern with #3 Braunamid
• An interrupted suture should be placed at bottom of incision to allow ventral drainage if needed