Chapter 41 - Postoperative care, complications Flashcards
What is a common postoperative complication in horses suffering from strangulating small intestine disease?
Ileus
What syndrome is frequently associated with exaggerated immune responses in horses with GI disease?
SIRS (Systemic Inflammatory Response Syndrome)
What is a frequent cause of systemic inflammatory response syndrome in horses with GI disease?
Endotoxemia
Which organ systems are at increased risk of dysfunction in horses with SIRS?
Pneumonia and renal failure
What should postoperative monitoring for GI disease include in addition to physical examinations?
Clinical pathologic assessment
What are the key indicators to be monitored postoperatively in horses with GI disease?
- Pain,
- mucous membrane color,
- heart rate,
- respiratory rate,
- urine/fecal production,
- extremities,
- temperature
What gastrointestinal parameters are essential to evaluate postoperative GI function?
- Appetite, GI sounds,
- fecal production,
- fecal consistency
What is often used to investigate poor postoperative GI response in horses?
- Nasogastric intubation,
- rectal palpation,
- abdominal ultrasonography
What factor increases the frequency of monitoring in postoperative horses with GI disease?
Strangulating lesions
What are two undesirable side effects of NSAIDs in postoperative horses?
- Gastrointestinal ulceration
- nephrotoxicity
Which enzyme does COX-2 selective NSAIDs target to reduce inflammation?
COX-2 (Cyclooxygenase 2)
What synthetic opiate is used to control postoperative pain in horses?
Butorphanol dose 13 microgram/kg/hr in CRI
What is the classification of butorphanol?
Butorphanol is a mu opioid antagonist with low intrinsic activity and kappa opioid agonist exhibiting high affinity.
What is the loading dose of lidocaine for postoperative ileus management in horses?
1.3 mg/kg IV followed by 0.05 mg/kg/min IV
What plasma-derived therapy binds circulating endotoxin in horses with SIRS?
Hyperimmune plasma 20–40 mg/kg BW
What therapy is used to prevent laminitis in horses with SIRS?
Digital cryotherapy
At what temperature should the digits be cooled to reduce laminitis risk in horses with SIRS?
4°C
NSAID, frozen hyeprimune plasma and__________which bind circulating endotoxin and may provide some clinical benefit
Polymyxin B 1000–6000 IU/kg q 8–12 hours IV
What adverse effects can occur due to lidocaine toxicity in horses?
Muscle tremors, altered visual function, anxiety, ataxia, collapse
Lidocaine toxicity can be exacerbated with concomitant use of higlhy protein bound drugs such as
ceftiofur
How does it work Lidocaine?
Lidocaine prevents propagation of action potentials by binding to sodium channels, and may exert prokinetic effects through smooth muscle membrane alteration
Lidocaine has also been shown to ameliorate the inhibitory effects of flunixin meglumine on ______________ of the _____________ (2w)
recovery of the mucosal barrier
What 2 drugs are more selective to inhibit the COX-2 but not COX-1?
meloxicam and firocoxib
What are common postoperative electrolyte imbalances in horses?
K+, Ca2+, Mg2+
What is the daily fluid maintenance requirement for adult horses?
50-60 mL/kg
How much fluid do foals need daily?
70-80 mL/kg
What organ is responsible for recovering a large volume of water in horses?
Large colon
Which solution contains calcium and lactate as a buffer?
Lactated Ringer solution
What is the goal of therapy in horses with severe SIRS postoperatively?
Maintain vascular volume
What heart rate is a reasonable indicator of adequate vascular volume?
< 80 beats/min
At what PCV should therapy be adjusted in horses postoperatively?
< 50%
What total protein level indicates the need for colloid administration?
< 4.1 g/dL
What colloids are available for administration to horses?
Plasma,
dextrans,
hydroxyethyl starch (voluven)
What is the half-life of potassium penicillin in horses?
80 minutes
How often is potassium penicillin administered perioperatively?
Every 6 hours
What is the typical dose for gentamicin in horses postoperatively?
6.6 mg/kg IV
What postoperative duration of antimicrobials showed no difference in infection rates?
3 vs. 5 days
How soon can feeding be resumed after surgery in small intestinal disorders?
12 hours
When can feeding be resumed after surgery in large colon disorders?
6-8 hours
What laxative is recommended postoperatively for impactions?
Mineral oil
What percentage of horses experience recurrent abdominal pain postoperatively?
28-30%
What GI procedure is associated with a higher prevalence of postoperative colic?
Small intestinal resection
Within how many hours post-surgery does colic due to original lesion recurrence occur?
72 hours
What are common nongastrointestinal sources of postoperative abdominal pain?
Peritonitis, surgical incision pain
What causes of postoperative colic are likely 5 to 7 days after surgery?
Adhesions, recurrence, new GI lesion
What diagnostic tools help in postoperative decision-making for colic?
Physical exam, rectal palpation, ultrasonography
What can be challenging to differentiate post-surgery in horses?
Ileus vs. intestinal obstruction
What is a common treatment for postoperative colic without second surgery?
Medical therapy, NSAIDs, spasmolytics
What spasmolytic medication can be used in postoperative colic treatment?
N-butylscopolammonium bromide 0.3 mg/kg
What is the most common reason for postoperative death in horses?
Postoperative colic
What is the suggested prognosis for horses experiencing colic within 48 hours post-surgery?
Good with medical therapy
What increases the risk of postoperative death or euthanasia in horses?
Postoperative colic
What major fluid loss problem occurs with large colon volvulus?
Capillary permeability increase
What is the oncotic pressure threshold below which colloids should be administered?
12 mm Hg
What factor should be monitored every 6 hours postoperatively in horses with fluid loss?
PCV, TP
How long does it take for capillary permeability to be restored in surviving horses?
24-36 hours
What syndrome delays feeding resumption in large colon torsion cases?
Systemic inflammatory response syndrome (SIRS)
What factor is a common dilemma postoperatively in horses with colic?
Distinction between ileus and obstruction
What is the common term for motility dysfunction of the small intestine in horses after GI surgery?
Postoperative Ileus (POI)
What range of prevalence is reported for POI in horses undergoing all types of colic surgeries?
9.6% to 21%
What range of POI-associated death or euthanasia is reported in studies?
30% to 76%
Which condition often leads to POI in horses?
Small intestine strangulating lesions
How many liters of reflux at admission is a risk factor for developing POI?
More than 8 L
What duration of anesthesia increases the risk of POI?
More than 2.5 hours
.
.
What substance is administered intraoperatively to decrease the risk of POI?
Lidocaine
What age is considered a risk factor for developing POI in horses?
Greater than 10 years
What is a common clinical sign of POI due to gas and fluid accumulation in the intestines?
Gastric distention
Which breed of horse is more prone to developing POI?
Arabian
What abdominal surgery often leads to POI besides small intestine procedures?
Large colon volvulus
What hematologic paramete is a risk factor for POI?
PCV higher than 45%
What is a common electrolyte imbalance seen in POI?
Low K+ and Cl−
Which inflammatory mediator is implicated in motility disruption during POI?
Prostaglandin E2 (PGE2)
What is the primary physiological disruption that leads to POI?
Sequestration of fluid, gas, and ingesta
What inflammatory mediator, besides prostaglandins, disrupts motility in POI?
Tumor Necrosis Factor (TNF)
Within how many hours post-anesthesia does gastric distention typically occur in POI?
12 to 48 hours
What common symptom indicates pain from GI distention in horses with POI?
Flank watching
Which prokinetic drug has shown potential benefit but requires further trials?
Neostigmine
What neurotransmitter is involved in excitation of GI smooth muscle in horses?
Substance P (SP)
Which neurotransmitter inhibits GI smooth muscle activity during POI?
Nitric Oxide (NO)
What type of cells help mediate contractility in the GI system and are affected during POI?
Interstitial cells of Cajal
What receptor antagonist is identified as a potential treatment in human POI?
Mu receptor antagonist
Which pharmacologic agents have limited clinical evidence for efficacy in POI treatment?
Erythromycin and cisapride
What parasympathomimetic agent has historically been used to increase GI motility in POI?
Bethanechol
What is Bethanechol chlorid?
muscarinic cholinergic agonist (cholinomimetic or parasympathomimetic that stimulates ACh receptors (1arly M3 but also M2 receptors on GI smooth muscles at the levels of myenteric plexus causing GI contractile activity
Which intravenous drug, besides NSAIDs, is used for its anti-inflammatory properties in POI?
Lidocaine
What condition must be ruled out if a horse does not respond to POI treatment within 48 hours?
Mechanical obstruction
Jacobs et al 2019 VS Use of perioperative variables to determine the requirement for repeat celiotomy in horses with postoperative reflux after small intestinal surgery - What perioperative variable was NOT found to be associated with a surgical reason for postoperative reflux (POR) after small intestinal (SI) surgery in horses?
A) Postoperative fever
B) Timing of colic in the postoperative period
C) Greater volume of POR
D) Timing of POR resolution
C) Greater volume of POR
What was considered a medical reason for POR in horses after SI surgery?
A) Anastomosis complications
B) Mechanical obstruction
C) Nonviable intestine
D) Resolution of POR with medical management or no surgical reasons found at repeat surgery/necropsy
D) Resolution of POR with medical management or no surgical reasons found at repeat surgery/necropsy
According to the study, which of the following variables indicated a higher likelihood of a surgical reason for POR after SI surgery?
A) Duration of POR
B) Presence of a postoperative fever
C) Low volume of reflux
D) Normal rectal temperature
B) Presence of a postoperative fever and colic
Historically, pharmacologic modulation of GI motility in the horse has been directed at increasing excitatory cholinergic activity with administration of parasympathomimetic agents, name 2
bethanechol or neostigmine
In addition to being affected by sympathetic and parasympathetic input, contractility of GI muscle is directly mediated by enteric inhibitory neurotransmitters such as
- vasoactive intestinal peptide (VIP),
- adenosine triphosphate (ATP),
- nitric oxide (NO),
- calcitonin gene-related peptide (CGRP),
- and enteric excitatory neurotransmitters such as substance P (SP)
- and acetylcholine (ACh).
What type of drug is Bethanechol?
A) Adrenergic agonist
B) Cholinergic agonist
C) Dopamine antagonist
D) Serotonin agonist
B) Cholinergic agonist
Which receptor does Bethanechol primarily stimulate to cause gastrointestinal contractile activity?
A) M1 receptors
B) M2 receptors
C) M3 receptors
D) Nicotinic receptors
C) M3 receptors
Bethanechol has been shown to increase contractile activity in which sections of the horse’s GI tract?
A) Stomach and jejunum
B) Duodenum, jejunum, cecum, and pelvic flexure
C) Pelvic flexure and ileum
D) Cecum and large colon
B) Duodenum, jejunum, cecum, and pelvic flexure
In normal horses, what effect does Bethanechol have on gastric and cecal emptying?
A) Delays emptying
B) Increases the rate of emptying
C) Decreases motility
D) Causes ileus
B) Increases the rate of emptying
In a postoperative ileus (POI) model in ponies, Bethanechol combined with which drug shortened transit time?
A) Yohimbine
B) Acepromazine
C) Cisapride
D) Neostigmine
A) Yohimbine
Which drug was more effective than Bethanechol in restoring coordinated gastroduodenal motility patterns in a POI model in ponies?
A) Acepromazine
B) Yohimbine
C) Neostigmine
D) Metoclopramide
D) Metoclopramide
What is the recommended dosage of Bethanechol in horses?
A) 0.05 mg/kg SC every 3-4 hours
B) 0.025 mg/kg SC every 3-6 hours
C) 0.01 mg/kg IV every 6-8 hours
D) 0.1 mg/kg IM every 12 hours
B) 0.025 mg/kg SC every 3-6 hours
What are the most common side effects of Bethanechol?
A) Hypertension and tachycardia
B) Abdominal cramping and diarrhea
C) Respiratory depression and nausea
D) Dry mouth and constipation
B) Abdominal cramping and diarrhea
Neostigmine works as a prokinetic by:
A) Blocking dopamine receptors
B) Retarding the breakdown of acetylcholine
C) Stimulating serotonin release
D) Inhibiting norepinephrine synthesis
B) Retarding the breakdown of acetylcholine
Neostigmine delays gastric emptying and decreases motility in which GI section?
A) Cecum
B) Stomach and jejunum
C) Pelvic flexure
D) Duodenum
B) Stomach and jejunum
What effect does Neostigmine have on the pelvic flexure in horses?
A) Decreases motility
B) Increases propulsive motility
C) Causes distention
D) Reduces contractions
B) Increases propulsive motility
Which of the following is a side effect commonly seen with Neostigmine use?
A) Excitement
B) Abdominal pain
C) Hypotension
D) Tachycardia
B) Abdominal pain
What is the recommended initial dosage of Neostigmine for horses?
A) 0.022 mg/kg IV
B) 0.01 mg/kg SC
C) 2 mg/adult horse SC
D) 1 mg/adult horse IM
C) 2 mg/adult horse SC
Adrenergic antagonists like Acepromazine are used based on the assumption that:
A) Parasympathetic hyperactivity contributes to POI
B) Sympathetic hyperactivity contributes to POI
C) Dopamine inhibits GI motility
D) Acetylcholine enhances GI motility
B) Sympathetic hyperactivity contributes to POI
Which of the following drugs is a selective α2-adrenergic antagonist?
A) Acepromazine
B) Metoclopramide
C) Yohimbine
D) Neostigmine
C) Yohimbine
Metoclopramide’s prokinetic effects result from antagonism of which receptors?
A) 5-HT4 and DA2
B) M3 and DA1
C) 5-HT3 and M2
D) M3 and 5-HT2
A) 5-HT4 and DA2
Which neurotransmitter’s release is inhibited by stimulation of α2-receptors?
A) Serotonin
B) Dopamine
C) Norepinephrine
D) Acetylcholine
D) Acetylcholine
In a POI model in ponies, Metoclopramide was more effective in restoring GI coordination compared to:
A) Cisapride
B) Bethanechol
C) Yohimbine
D) Acepromazine
B) Bethanechol
What is the main prokinetic activity of Metoclopramide in horses?
A) Dopamine receptor stimulation
B) Serotonin receptor antagonism
C) Acetylcholine release inhibition
D) Stimulating in vitro circular muscle contractility
D) Stimulating in vitro circular muscle contractility
What is the common dosage of Metoclopramide in horses when administered IV?
A) 0.01 mg/kg over 20 minutes
B) 0.1 mg/kg over 10 minutes
C) 0.25 mg/kg diluted in 500 mL of saline over 30-60 minutes
D) 0.5 mg/kg diluted in 200 mL of saline over 15 minutes
C) 0.25 mg/kg diluted in 500 mL of saline over 30-60 minutes
Metoclopramide can cause which side effect in horses?
A) Bradycardia
B) Excitement and restlessness
C) Respiratory depression
D) Abdominal bloating
B) Excitement and restlessness
Cisapride’s prokinetic effect is primarily mediated through which receptor agonism?
A) 5-HT4
B) DA2
C) M3
D) α2
A) 5-HT4
Why was Cisapride taken off the human market in most countries?
A) Lack of efficacy
B) Cardiovascular toxicities
C) Gastrointestinal side effects
D) Poor absorption
B) Cardiovascular toxicities
Tegaserod acts on which receptor to enhance GI motility?
A) 5-HT4
B) 5-HT2
C) DA2
D) M2
A) 5-HT4
Which of the following effects does Cisapride have in horses?
A) Increases motility in the cecum only
B) Decreases gastric emptying
C) Stimulates coordinated activity in the ileocecocolonic junction
D) Reduces myoelectric activity in the colon
C) Stimulates coordinated activity in the ileocecocolonic junction
What effect does Tegaserod have in normal horses?
A) Delays gastric emptying
B) Increases GI transit time
C) Reduces gut sounds
D) Reduces the frequency of defecation
B) Increases GI transit time
What dosage of Tegaserod was found appropriate to reach therapeutic concentrations in normal horses?
A) 0.1 mg/kg PO BID
B) 0.5 mg/kg IV BID
C) 0.27 mg/kg PO BID
D) 0.02 mg/kg IV BID
C) 0.27 mg/kg PO BID
Which receptor is not functionally present in the equine jejunum?
A) 5-HT4
B) M2
C) DA1
D) 5-HT1a
A) 5-HT4
Which drug combination was effective in reducing the severity of POI in horses?
A) Metoclopramide and Yohimbine
B) Bethanechol and Neostigmine
C) Bethanechol and Yohimbine
D) Cisapride and Neostigmine
C) Bethanechol and Yohimbine
What effect does Yohimbine have on cholinergic neurons?
A) Stimulates α2-receptors
B) Inhibits norepinephrine synthesis
C) Enhances acetylcholine release
D) Blocks serotonin release
C) Enhances acetylcholine release
Which drug causes extrapyramidal side effects such as excitement and restlessness in horses?
A) Cisapride
B) Tegaserod
C) Metoclopramide
D) Neostigmine
C) Metoclopramide
Which drug has been associated with cardiovascular toxicities in humans, limiting its availability?
A) Tegaserod
B) Metoclopramide
C) Yohimbine
D) Acepromazine
A) Tegaserod
What is a contraindication for using Neostigmine in horses?
A) Cecal impaction
B) Gastric motility issues
C) Ileal obstruction
D) Small intestinal distention
D) Small intestinal distention
Acepromazine maleate is what type of adrenergic antagonist?
A) α1-selective
B) α2-selective
C) Nonselective α-adrenergic
D) Nonselective β-adrenergic
C) Nonselective α-adrenergic
Which prokinetic drug works by blocking dopamine receptors and stimulating serotonin receptors?
A) Metoclopramide
B) Cisapride
C) Tegaserod
D) Neostigmine
A) Metoclopramide
What is the main concern with the use of adrenergic antagonists as prokinetics in equine clinical cases?
A) Lack of efficacy
B) Cardiovascular side effects
C) Increased risk of POI
D) Excessive smooth muscle contractio
D) Excessive smooth muscle contraction
Which prokinetic drug has been shown to significantly decrease the incidence of POI in horses in clinical trials?
A) Neostigmine
B) Cisapride
C) Bethanechol
D) Yohimbine
B) Cisapride
what type of drug is N-methylnaltrexone?
Opioid antagonist
What does N-methylnaltrexone directly stimulate in vitro?
Jejunal muscle strips
What dose of N-methylnaltrexone attenuates the effects of morphine in horses?
0.75 mg/kg IV BID
hat effects does N-methylnaltrexone have when administered with morphine?
Increases defecation frequency
Increases fecal weight
Prevents increased transit time
Which receptor does Alvimopan act on?
Mu receptor
Why is Alvimopan potentially less useful in horses?
Differences in POI pathophysiology
What type of drug is Erythromycin lactobionate?
Macrolide antibiotic
What additional action does erythromycin have besides being an antibiotic?
Motilin agonist
What type of hormone is motilin?
GI motility hormone
Where is motilin released from?
Enterochromaffin cells
What receptors does erythromycin influence besides motilin receptors?
5-HT3 receptors
What phase of the migrating motor complex does erythromycin initiate?
Phase III
What happens when erythromycin is administered at subtherapeutic antimicrobial levels?
Stimulates gastric emptying
How does erythromycin influence cecal emptying in horses?
Dose-dependent response
What dosage of erythromycin stimulates both cecal and small intestinal contractile activity in horses?
1 mg/kg
What dosage of erythromycin can disrupt propulsive activity?
> 10 mg/kg
What happens with repeated erythromycin treatments?
Reduced prokinetic response
Why does erythromycin treatment show desensitization over time?
Downregulates motilin receptors
What GI side effect is associated with low-dose erythromycin in horses?
Clostridium difficile colitis
What motility disorder is erythromycin used to treat in humans?
Gastroparesis
What class of drugs does lidocaine belong to?
Sodium channel blocker
What effect does intravenous lidocaine have after abdominal surgery in humans?
Shortens paralytic ileus
List two mechanisms proposed for the pathogenesis of POI.
- Sympathetic inhibitory reflexes
- Inflammatory cell influx
What are the primary methods of action of lidocaine in reducing POI?
- Reduces inflammation
- Stabilizes cell permeability
- Reduces pain
What is one of the effects of lidocaine on prostaglandins?
Inhibits synthesis
How does lidocaine affect the sympathetic response?
Inhibits sympathoadrenal response
In an ischemia-reperfusion model, what did lidocaine reduce in horses?
Plasma prostacyclin E2-metabolite
What did lidocaine ameliorate in horses treated with flunixin?
Mucosal neutrophil counts
What effect did lidocaine have on the proximal duodenum in vitro?
Increased contractility
How does prophylactic administration of lidocaine during surgery affect POI risk?
Decreases reflux duration
What is the initial bolus dose of lidocaine in horses?
1.3 mg/kg IV
What is the continuous infusion rate of lidocaine after the bolus?
0.05 mg/kg/min
When should lidocaine CRI be discontinued in surgery?
30 minutes before end
What condition increases the risk of lidocaine complications?
Hypoproteinemia
How frequently should lidocaine blood concentrations be monitored in high-risk horses?
Every 4-6 hours
Prognosis of horses with POI?
Despite the fact that at least 30% of affected horses will die or be euthanized as a result of POI, the prognosis for eventual resolution of the condition can be favorable.
What percentage of horses develop postoperative adhesions?
9% to 27%
When are most pathological adhesions recognized postoperatively?
First 2 months
What percentage of horses with two laparotomies develop significant adhesions?
50%
What percentage of horses with a single laparotomy develop significant adhesions?
5.7%
What is the survival rate of horses with adhesions after the second surgery?
24% to 50%
What is the reported adhesion formation rate in foals following abdominal surgery?
8% to 17%
What specific condition is a risk factor for adhesion formation?
Small intestinal strangulation
Which type of surgical gloves increases the risk of adhesion formation?
Powdered gloves
What is the only definitive way to identify postoperative adhesions?
Postmortem or repeat laparotomy
What is the most common symptom of adhesions?
Colic
How can surgically accessible adhesions be treated?
Sharp transection
What device can be used for adhesiolysis?
Vessel sealing device (Ligasure)
What should be avoided during adhesiolysis using a vessel sealing device?
Thermal trauma
What type of adhesions can be left in place with an incomplete bypass?
Widespread or inaccessible adhesions
What is the outcome of many adhesiolysis procedures?
Reformation of adhesions
What is more effective than treating existing adhesions?
Prevention
What is the most important strategy to prevent adhesions?
Minimizing trauma
What happens when mesothelial cells are disrupted?
Connective tissue exposure
What vasoactive substances are released from the submesothelial tissue?
PGE2, serotonin, bradykinin, histamine
What activates the clotting cascade during adhesion formation?
Thromboplastin
What enzyme converts fibrinogen to fibrin?
Thrombin
What enzyme is responsible for lysing fibrin tags?
Plasmin
How long does it take for the mesothelial layer to cover peritoneal injuries?
2 to 5 days
What happens if there is inadequate fibrinolysis?
Fibrous adhesions form
What protease converts plasminogen to plasmin?
Tissue plasminogen activator (TPA)
What condition tips the balance in favor of adhesion formation?
Extensive peritoneal damage
What inflammatory mediator is elevated in horses with peritonitis?
Transforming growth factor beta (TGF-β)
How are abdominal adhesions definitively identified?
Laparoscopy, repeat laparotomy, or postmortem
Which medications are commonly used perioperatively to reduce inflammation?
NSAIDs and antibiotics
What combination of drugs has been shown to reduce adhesion formation in horses?
Penicillin/cephalosporin and gentamicin with an NSAID
What dosage of DMSO is used to reduce inflammation?
20 mg/kg IV BID for 72 h
What effect does lidocaine have on COX-2 expression in horses?
Reduces COX-2 expression
What higher lidocaine concentrations increase?
Neutrophil migration and adhesion formation
What type of heparin binds to antithrombin (AT)?
Heparin sodium
Which clotting factors are inactivated by the AT-heparin complex?
Factors IX, X, XI, XII, thrombin
What is the recommended calcium heparin initial dose?
150 IU/kg SC
What is the most common complication of heparin therapy in horses?
Anemia induced by erythrocyte agglutination, which resolves in 3 to 4 days following cessation of heparin
What type of heparin has fewer side effects in horses?
Low-molecular-weight heparin (LMWH)
Heparin is composed by
sulfated glycosaminoglycans synthetized by conenctive tissue mast cells
How does it work the heparin?
by binding to antithrombin (AT), a glycoprotein synthesized in the liver and vascular endothelium, heparin markedly enhances the rate of AT-mediated inactivation of clotting factors (factors IX, X, XI, and XII, and thrombin).152,153
Low-molecular-weight heparin (LMWH) consists in what?
Low-molecular-weight heparin (LMWH) is separated from heparin, or unfractionated heparin (UFH), by solvent or gel filtration and consists of smaller molecules than UFH. It has less antithrombin activity and higher antifactor Xa activity than UFH
What effect does SCMC have on the bowel?
Siliconizing effect
What is the concentration of SCMC used in horses?
1% solution
What volume of SCMC is infused per kg of body weight in horses?
7 mL/kg
When is SCMC infused during surgery?
Before bowel manipulation
What does SCMC primarily act as during surgery?
Mechanical barrier
Does SCMC have any adverse effects on incisional wound healing?
No adverse effects
What accumulates intracellularly in macrophages after SCMC use?
Pink/magenta-colored material
What kind of study found SCMC useful in prolonging survival in horses?
Retrospective study
What is the main effect of sodium hyaluronate (HA) on the jejunum?
Reduces adhesions
In horses, what does SCMC help reduce postoperatively?
Colic or POI
What is the concentration of HA applied to the serosal surface?
0.4% solution
What type of membrane helps reduce adhesion formation?
Bioresorbable HA-CMC membrane
What has been combined with SCMC to reduce adhesions?
Sodium hyaluronate
What are the proposed mechanisms of fucoidan’s antiadhesive effects?
Anticoagulant properties
What molecular characteristic of fucoidan contributes to its effect?
High molecular weight
Did fucoidan affect biochemical parameters or anastomoses healing?
No significant effects
What was delayed in horses treated with fucoidan?
Linea alba healing
Is the clinical significance of delayed healing due to fucoidan known?
Unknown
What mechanism is proposed for crystalloid solutions preventing adhesions?
Hydroflotation
What potential issue arises with large volumes of crystalloids?
Compromised infection response
What is the alternative to using crystalloids to prevent adhesions?
Peritoneal lavage
What solution is used for standing postoperative lavage?
Lactated Ringer
How many liters of solution are used per lavage?
10 L
What is the reported complication rate for intraabdominal drains?
High incidence
What percentage of horses experience partial drain obstruction?26%
26%
What percentage of horses experience leakage around the drain?
16%
What percentage of horses experience subcutaneous fluid accumulation?
12%
What is a rare but serious complication after exploratory laparotomy?
Septic peritonitis
What is the survival rate in horses with septic postoperative peritonitis?
56% don’t survive
What are the key inflammatory mediators in septic peritonitis?
Histamine, prostaglandins
Where are bacteria cleared from the peritoneal cavity?
Diaphragmatic lymphatics
What is a critical diagnostic method for septic peritonitis?
Peritoneal fluid analysis
Ceel count, TP, lactate, serum-peritoneal glucose difference greater than 50 mg/Dl or peritoneal pH less than 7.2
peritoneal glucose of less than 30 mg/dL
What is a key indicator of septic peritonitis in glucose testing?
Glucose difference > 50 mg/dL
What bacteria are commonly isolated in septic peritonitis?
E. coli, Staphylococcus, Streptococcus and Rhodococcus equi
Anerobic Bacteroirds Clostridium and Fusobacterium
What is the most significant risk factor for incisional herniation?
Incisional infection
What type of drain system helps manage septic peritonitis?
Closed fenestrated drain
Parasympathomimemetics there are 2 main, name them
Bethanecol and neogstigmine
Bethanecol is a
muscarinic cholinergic agonist that stimultaes Ach (parasympathomimetic)
Neoftigmine is a
cholinesterase inhibitor that prolong ACh activity (parasympathomimetic)
Name the 4 benzamides
- Metaclopramide
- Cisapride
- Mosapride
- Tegaserod
Which are the opiate antagonist?
N-methylnaltrexone (acts in jejunal muscle strips)
Alvimopen (lack of evidence in horses, only humans)
Which are the motilin agonist?
Erythromycin that acts on motilin (0.5-1 mg/kg
Which are the sodium channel blockers?
Lidocaine taht diminsih catecholamins
What percentage of horses undergoing colic surgery experience jugular vein thrombophlebitis?
7.5% to 10%
What vein is commonly catheterized in horses with GI disease?
Jugular vein
Name 2 risk factors for jugular vein thrombophlebitis in horses with catheters.
- Endotoxemia
- hypoproteinemia
What vital sign upon admission is a risk factor for jugular vein thrombophlebitis?
Heart rate
Which blood parameter upon admission is a risk factor for jugular vein thrombophlebitis?
PCV
Which GI condition increases the risk of jugular vein thrombophlebitis?
Large intestinal disease
What bacterial infection is linked to increased thrombophlebitis risk?
Salmonellosis
Which systemic process contributes to jugular vein thrombophlebitis?
Systemic inflammation
Name a symptom a horse with jugular vein thrombosis may exhibit.
Febrile
What is the typical feel of a thrombosed jugular vein on palpation?
Corded, hot, hard, painful
What is the difference in symptoms between bacterial and non-bacterial thrombophlebitis?
More marked symptoms in bacterial
Bilateral thrombosis of the jugular vein can lead to what symptom?
Head and neck swelling
What imaging technique is useful for diagnosing jugular vein thrombosis?
Ultrasonography
What should be done at the first sign of jugular vein thrombosis?
Remove catheter
What should be cultured after catheter removal in thrombophlebitis cases?
Catheter tip
Name an alternative catheterization site when the jugular vein is compromised.
Superficial thoracic vein
What is a topical treatment applied to acutely thrombosed veins?
DMSO with antibiotics or NSAIDs
What systemic therapy is considered for bacterial thrombophlebitis?
Systemic antibiotics
How long does it take for most jugular vein thromboses to become asymptomatic?
Months
What procedure is described for chronic thrombosis of the jugular vein?
Surgical removal
Name a catheter material that reduces thrombophlebitis risk.
Polyurethane
What is essential for reducing the risk of jugular vein thrombophlebitis during catheterization?
Sterile insertion
Timely removal of unnecessary kt
What complication occurs in 0.4% to 1% of horses undergoing GI surgery?
Laminitis
Horses experiencing what condition are at increased risk of laminitis?
SIRS
What preventative treatment is mentioned for laminitis?
Digital cryotherapy
What percentage of horses recover from anesthesia after GI surgery?
74% to 85%
What percentage of horses return to athletic performance after GI surgery?
63% to 85%
What percentage of horses require a second surgery after celiotomy?
8% to 10%
Name two complications that may require a second surgery after celiotomy.
Ileus, hemoperitoneum
What is a frequent finding during second surgery for colic?
Adhesions
Name one possible recurrent lesion after GI surgery.
Large colon displacement
What is an important surgical technique to prevent complications during epiploic foramen entrapment?
Gentle reduction of bowel
What type of suture pattern is recommended for large colon enterotomies?
Full-thickness suture pattern
What is a potential complication of intestinal resection?
Internal herniation
Name one closure technique to prevent internal herniation.
Mesenteric closure
What procedure can be considered for recurrent large colon torsion?
Colopexy
What procedure has an increased risk of complications: jejunocecostomy or ileocecal fold closure?
Jejunocecostomy
What is the survival rate of horses after two laparotomies?
Median 778 to 1200 days
What are the main incisional complications after exploratory celiotomy?
Infection, dehiscence, herniation
What is the most common range reported for incisional infection rates?
15-25%
What is the incisional infection rate after two or more celiotomies?
87.5%
What body weight is a risk factor for incisional infection?
> 300 kg
What age is considered a risk factor for incisional infection?
> 1 year
What leukocyte condition on admission is a risk factor for incisional infection?
Leukopenia or leukocytosis
What duration of colic signs increases the risk of incisional infection?
> 24 hours
What admission heart rate is a risk factor for incisional infection?
> 60 beats/min
What fibrinogen-related risk factor is associated with incisional infections?
Elevated peritoneal fibrinogen
What intraoperative condition is a risk factor for incisional infection?
Hypoxemia
Which suture pattern is associated with increased risk of incisional infection?
Near-far-far-near
Name one material associated with higher rates of incisional infection.
Chromic catgut
What postoperative complication increases the risk of infection?
Incisional edema
Which skin closure technique is associated with a higher infection risk?
Staples for skin closure
What surgeon characteristic increases the risk of incisional infection?
Less-experienced surgeons
What factor did not reduce incisional complications?
Antibacterial-coated suture
What protective factor can reduce incisional drainage?
Abdominal bandages
What type of bacterial growth predicts incisional infection within the first 24 hours?
Significant bacterial growth
What is the reported rate of incisional hernia after celiotomy?
13% to 16%
Horses with incisional infections are how many times more likely to develop hernias?
17.8 times
What systemic condition increases bacterial invasion risk in horses with GI disease?
SIRS
Name one common symptom of postoperative incisional infection.
Heat, pain, swelling
How long after surgery do most incisional infections develop?
3 days or more
What action is recommended upon recognizing an incisional infection?
Encourage drainage
What is one treatment concern when lavaging draining tracts?
Potentiating infection
What type of abdominal support is recommended during incisional infection management?
Protective abdominal support
What surgical technique is crucial for preventing incisional infections?
Efficient surgical time
How long should hernias be left before considering surgical repair?
Minimum 3 months
Hill et al 2020 EVJ What was the median BMI of horses that developed incisional complications in the study?
A) 199.1 kg/m²
B) 203.6 kg/m²
C) 191.5 kg/m²
D) 210.2 kg/m²
B) 203.6 kg/m², positive relationship between body mass index and surgical site infection
Hill 2020 EVj Which factor showed an association with BMI but not with incisional complication risk?
A) Age
B) Sex
C) Breed
D) Metabolic disease
C) Breed
Hill, 2020 EVJ what was the prevalence of incisional complications in the study population?
A) 15.7%
B) 23.7%
C) 33.6%
D) 28.7%
B) 23.7%
Hann, 2021 EVJ Acute abdominal dehiscence following laparo is a rare but fatal condition that occurs in mean how many days post op?
5 days
Hann, 2021 EVJ Acute abdominal dehiscence following laparo is a rare but fatal condition twhat was the significant precursor in 44% of cases?
Surgical Site infection SSI
Hann, 2021 EVJ Acute abdominal dehiscence following laparo is a rare but fatal condition survival to discharge? are broodmares prone?
39% and it happens through linea alba or rupture of muscle wall adjacent to it
25% of the 44% horses were broodmares
Weatherall et al 2020 VS Which type of abdominal bandage resulted in the highest bursting pressure in the study?
A) No bandage B) Elastic bandage C) Velcro inelastic bandage D) No difference between groups
B) Elastic bandage
Weatherall et al 2020 VS Where was the location of failure most commonly observed in the Velcro inelastic bandage group?
A) Linea alba B) Diaphragm C) Incision site D) Bladder
B) Diaphragm
Which type of glove had a higher rate of perforation during the jejunojejunal anastomoses in equine cadavers?
A) Tri-layer nitrile-latex gloves B) Natural rubber latex gloves C) No difference between glove types D) Both had the same rate
B) Natural rubber latex gloves,
Tri-layer nitrile-latex gloves were more resistant
Averay 2021 VS What was the odds ratio of perforation when using tri-layer nitrile-latex gloves compared to natural rubber latex gloves?
A) 1.5 times lower B) 2.2 times lower C) 5.6 times lower D) 7.1 times lower
C) 5.6 times lower
Gandini eta al 2022 EVJ % of POC
% of Postop colic, %incisional and % peritonitis
57.7% POC
47.7% Postop reflux
44% incisional
30% peritonitis
Kilcoyne 2019 JAVMA Which group had the highest incidence of incisional infection in the study?
A) Group 1 (sterile cotton towel) B) Group 2 (polyhexamethylene biguanide-impregnated dressing) C) Group 3 (sterile gauze with iodine-impregnated adhesive drape) D) All groups had the same rate
C) Group 3 (sterile gauze with iodine-impregnated adhesive drape)
Kilcoyne 2019 JAVMA What was the mean duration that the dressings remained in place for Group 2 (polyhexamethylene biguanide-impregnated dressing)?
A) 31 hours B) 44 hours C) 24 hours D) 50 hours
A) 31 hours
Kylcoyne 2019 PHMB is superior to iodine-impregnated adhesive drape?
yes
Isgren 2019 EVJ What percentage of horses in the study developed a surgical site infection (SSI)?
A) 10% B) 22.6% C) 30% D) 50%
B) 22.6%
Isgren et al 2019 EVJWhich bacterial species were identified in the post-operative period but did not lead to SSI development?
A) MRSA and ESBL-producers B) Streptococcus and E. coli C) Pseudomonas and Clostridium D) Staphylococcus aureus and Bacillus
A) MRSA and ESBL-producers,
peni and genta had less SSI than pen alone
Isgren et al 2019 EVJ doing enterctomy had correlation with SSI and different bacteria SSI bateria than culture perop?
No
Gustafssin 2020 EVJ Intraincisional medical grade honey decreases the prevalence of incisional infection in horses undergoing colic surgery: A prospective randomised controlled study What was the percentage of incisional infections in the treatment group compared to the control group?
A) 8.2% vs. 32.5% B) 12% vs. 40% C) 15% vs. 25% D) 20% vs. 30%
A) 8.2% vs. 32.5%
Gustafsson 2020 EVJ What factor was identified as a significant risk for incisional infection post-surgery?
A) Older age B) Diarrhea 48 hours post-operatively C) Presence of fever D) Longer surgery duration
B) Diarrhea 48 hours post-operatively and the fact they were younger age
Gibbs EVJ 2021 Which 2 NSAIDs were the most commonly administered by clinicians in the post-operative care of equine colic patients?
A) Aspirin and Meloxicam
B) Flunixin and Phenylbutazone
C) Ibuprofen and Carprofen
D) Ketoprofen and Diclofenac
B) Flunixin and Phenylbutazone
Gibbs 2022 EVJ Which factor was most frequently ranked by clinicians as important when deciding to discontinue NSAIDs following colic surgery?
A) Duration of surgery
B) Absence of active colic signs
C) Age of the horse
D) Blood pressure levels
B) Absence of active colic signs and FEVER
Longland EVj 2020 Which of the following treatments led to the highest increase in pony body weight?
A) Total paddock area (TA)
B) Strip grazing without a back fence (SG1)
C) Strip grazing with a back fence (SG2)
D) Both SG1 and SG2 led to the same weight gain
A) Total paddock area (TA)
Longland EVj 2020 What was the main goal of the study on restricted grazing regimens for ponies?
A) To test different feed supplements for weight gain in ponies
B) To compare the effects of different restricted grazing methods on pony bodyweight (BW) and morphometric changes
C) To evaluate how ponies respond to various exercise programs
D) To assess the impact of free grazing on ponies’ health
B) To compare the effects of different restricted grazing methods on pony bodyweight (BW) and morphometric changes
