Colic II Flashcards
You come across a 14yr old QU gelding with..
Temp 100.8 HR 80 bpm RR: unable to assess MM: “muddy” CRT 3 sec
GI neg in all quadrants
Self induced trauma over the head/eyes
What do you do first?
NG tube
You come across a 14yr old QU gelding with..
Temp 100.8 HR 80 bpm RR: unable to assess MM: “muddy” CRT 3 sec
GI neg in all quadrants
Self induced trauma over the head/eyes
What additional diagnostics do you do?
Rectal
US
Abdominocentesis
You come across a 14yr old QU gelding with..
Temp 100.8 HR 80 bpm RR: unable to assess MM: “muddy” CRT 3 sec GI neg in all quadrants Self induced trauma over the head/eyes
NG tube — 10L of foul reflux
Rectal — multiple loops of distended from SI
US— stacked loops of thick SI
Abdominocentesis — serosanuinous, TP 3.4, cells 5000
Top DDX?
Strangulating lesion of small intestine due to severe colic signs, large amounts of reflux and distended SI loops
Most likely a strangulating lipoma due to age
Others:
Volvulus
Herniation
Intussusception
You are referring a patient for colic surgery. The center is 3 hours away form you. How should you prepare your patient for transport ?
Indwelling gNG tube
Hypertonic saline (4ml/kg) — provides CV support
For every 1L of hypertonic solution you give a horse, it should be followed up with ______ L of __________
10L of crystalloids
Minimum pre-op blood work for colic surgery?
PCV/TP Lactate CBC with differential Fibrinogen Glucose BUN/CREA
What is the best overall approach for colic surgery?
Ventral midline
— can exteriorize 75% of GIT
— minimal hemorrhage
—strong closure
What are you unable to exteriorize with a ventral midline approach?
Stomach Duodenum Distal ileum Base of cecum Distal RDC Transverse colon Terminal small colon
What are poor prognostic indicators for exploratory celiotomy?
Loss of negative pressure
Foul smell
Excessive/abnormal fluid
Excessive gas/abnormal bowel position
How do you work through the intestine when doing exploratory celiotomy?
Begin at cecum
Follow lateral band to cecocolic bank to RVC
Follow dorsal band to ileocecal fold to antimesenteric band of ileum
Run SI from ileum to duodenum
Exteriorize pelvic flexure
RVC from cecum cranial to sternal flexure caudally down LVC to pelvic flexure, cranially to LDC to diaphragmatic flexure to RDC to transverse colon
How do you decompress the SI?
Manual “milking” of contents to the cecum
Where do you find the duodenum?
Fixed to dorsal body wall and transverse colon by duodenocolic ligament
Runs from L to R behind root of mesentery to the ascending duodenum
Palpate cranial mesenteric artery
Follow duodenum to pylorus/stomach
Transverse colon runs in what direction?
Right to left
How do you close a ventral midline incision in the horse?
Large synthetic absorbable
— vicryl
—PDS
Short burst simple continuous (most common)
Cruciate
Simple interrupted
8-10throws at each end
Potential post op complications from colic surgery?
POI
Endotoxemia
Leakage from anastomosis site/peritonitis
Hemorrhage
Stricture at anastomosis site
When would you expect to see reflux from post op ileus?
In 12-24 hours post op
You have a 8yr warmblood mare that is violently colicky
Hx of Foaling 8 weeks ago This is her 3rd foal Current of vax and deworming On spring pasture
Owner gave 10ml banamine before calling
Top ddx??
Colon torsion
Based on foaling history this is most likely
How do you want to stabilize the following patient prior to surgery?
8yr old warmblood mare with suspected colonic torsion
HR 60
RR elevated
MM brick red with toxic line
Cool extremities
Severe pain
IV fluids — bolus
NSAIDS
AB :K + pen and gentocin
Tetanus prophylaxis
How are you going to assess tissue viability in a case of colonic torsion?
Color (serosa/mucosa)
Thickness
Pulse quality
Peristalsis
Fluorescein dye — IV
Surface oximetry
Doppler US
Luminal pressure
Histopath — gold standard
Common post op colic surgery electrolyte derangement?
Hypo Ca and Hypo Mg —> most common
K+ also (only get from diet and loss from diuresis or diarrhea)
What is the max rate of K+ administration?
0.5mEq/kg/L
Usually add 80mEq/ 5L bag
What are reasonable indicators that you are maintaining vascular volume post op?
HR <80
PCV <50%
TP >4.1
How often are you monitoring your patient post op?
And what tests are you doing?
Exam q1-3h
PCV/TP q6h
Gastric decompression q2-3hrs
CBC/Fibronogen/lactate/electrolyte one day post op and 3 days post op
Common post op medications for colic surgery?
Fluids (crytalloids) Antibiotics NSAIDS Lidocaine Gastric protectants \+/- colloids (plasma, hetastarch) Anti-endotoxin medications \+/- prokinetics
When can you discontinue post op medication?
When patient is eating, afebrile, normal CBC
Common post colic surgery complications?
Pain Endotoxemia Post-op ileus Colitis Incisional complications Adhesions Peritonitis Hemorrhage Laminitis
Clinical signs of post-op endotoxemia?
Tachycardia Abnormal mm (hyperemic, cyanotic) Pain Edema Hypomotility GI distention NG net reflux Thrombosis/coag disorders
How do you manage post-op endotoxemia?
Fluids
Flunixin meglumine
Antiendotoxin therapy
— di-tri-octahedral (DTO) smectite (biosponge) —> binds endotoxin
Polymixin B — binds lipid A
Plasma
Heparin therapy in cases of DIC
Risk factors for POI?
<10years old
PCV > 45%
High TP and albumin
Hyperglycemia
Anesthesia >2.5hrs Surgery >2hrs R/A SI lesions Ischemic small intestine
What is the most common lesion leading to post op ileus?
Strangulating SI lesions
Clinical sings of post op ileus?
Colic, depression Decrease/no borborygmi Elevated HR Increased PCV/TP Electrolyte derangement
Treatment for post op ileus?
Supportive therapy —NG decompression —fluids —electrolytes \+/-antibiotics
Prokinetics agents
— lidocaine
— metoclopramide
—erythromycin (can cause pain and colitis)
What function does lidocaine have in treatment of post op ileus?
Decrease catecholamines
Suppress primary afferent neuron activity
Directly stimulates smooth muscle
Inhibits prostaglandins —> decrease gut wall inflammation, granulocyte migration/lysosomal enzyme release, free radical production
What happens when you give a bolus of lidocaine ?
Toxicity!
Muscle fasciculation
Ataxia
Seizure
How does metoclopramide help treat post op ileus?
Increase ACH release
Stimulate smooth muscle in stomach and small intestine
What complications can arise from the incison site?
Infection
Hernia
Suture sinus formation
Acute incisional dehiscence
What is the most common complication from incisional infection?
Incision hernias
When do you want to repair an incisional hernia and why?
3 months after initial surgery
This allows boy wall to heal and fibrous tissue to form
Predisposing factors to acute total dehiscence?
Violent recovery
Severe post op pain
Prolonged surgery time
Continuous suture pattern
How can you prevent adhesions ?
Maintain intact mesothelial layer
Minimize trauma — good technique
Keep bowel wet
Hemostasis
Minimal suture exposure
Decide on surgery in timely manner
Peri-op NSAIDs and antibiotics
DMSO Heparin CMC 3% HA Omentectomy Peritoneal lavage
Causes of peritonitis?
Bowel necrosis
Anastomotic or enterotomy leakage
Contamination
How can you diagnose peritonitis?
Abdominocentesis
Toxic PMNs, bacteria
PH glucose
—serum: peritoneal glucose difference >50mg/dL
— peritoneal pH <7.2 with glucose <30mg/dl
CBC/fibrinogen
Left shift, thrombocytopenia, hypoproteinemia
