Chapter 41 - Postoperative care, complications Flashcards by Sofs C R

What is a common postoperative complication in horses suffering from strangulating small intestine disease?

Ileus

How well did you know this?

Not at all

Perfectly

What syndrome is frequently associated with exaggerated immune responses in horses with GI disease?

SIRS (Systemic Inflammatory Response Syndrome)

How well did you know this?

Not at all

Perfectly

What is a frequent cause of systemic inflammatory response syndrome in horses with GI disease?

Endotoxemia

How well did you know this?

Not at all

Perfectly

Which organ systems are at increased risk of dysfunction in horses with SIRS?

Pneumonia and renal failure

How well did you know this?

Not at all

Perfectly

What should postoperative monitoring for GI disease include in addition to physical examinations?

Clinical pathologic assessment

How well did you know this?

Not at all

Perfectly

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

How well did you know this?

Not at all

Perfectly

What gastrointestinal parameters are essential to evaluate postoperative GI function?

Appetite, GI sounds,
fecal production,
fecal consistency

How well did you know this?

Not at all

Perfectly

What is often used to investigate poor postoperative GI response in horses?

Nasogastric intubation,
rectal palpation,
abdominal ultrasonography

How well did you know this?

Not at all

Perfectly

What factor increases the frequency of monitoring in postoperative horses with GI disease?

Strangulating lesions

How well did you know this?

Not at all

Perfectly

What are two undesirable side effects of NSAIDs in postoperative horses?

Gastrointestinal ulceration
nephrotoxicity

How well did you know this?

Not at all

Perfectly

Which enzyme does COX-2 selective NSAIDs target to reduce inflammation?

COX-2 (Cyclooxygenase 2)

How well did you know this?

Not at all

Perfectly

What synthetic opiate is used to control postoperative pain in horses?

Butorphanol dose 13 microgram/kg/hr in CRI

How well did you know this?

Not at all

Perfectly

What is the classification of butorphanol?

Butorphanol is a mu opioid antagonist with low intrinsic activity and kappa opioid agonist exhibiting high affinity.

How well did you know this?

Not at all

Perfectly

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

How well did you know this?

Not at all

Perfectly

What plasma-derived therapy binds circulating endotoxin in horses with SIRS?

Hyperimmune plasma 20–40 mg/kg BW

How well did you know this?

Not at all

Perfectly

What therapy is used to prevent laminitis in horses with SIRS?

Digital cryotherapy

How well did you know this?

Not at all

Perfectly

At what temperature should the digits be cooled to reduce laminitis risk in horses with SIRS?

4°C

How well did you know this?

Not at all

Perfectly

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

How well did you know this?

Not at all

Perfectly

What adverse effects can occur due to lidocaine toxicity in horses?

Muscle tremors, altered visual function, anxiety, ataxia, collapse

How well did you know this?

Not at all

Perfectly

Lidocaine toxicity can be exacerbated with concomitant use of higlhy protein bound drugs such as

ceftiofur

How well did you know this?

Not at all

Perfectly

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

How well did you know this?

Not at all

Perfectly

Lidocaine has also been shown to ameliorate the inhibitory effects of flunixin meglumine on ______________ of the _____________ (2w)

recovery of the mucosal barrier

How well did you know this?

Not at all

Perfectly

What 2 drugs are more selective to inhibit the COX-2 but not COX-1?

meloxicam and firocoxib

How well did you know this?

Not at all

Perfectly

What are common postoperative electrolyte imbalances in horses?

K+, Ca2+, Mg2+

How well did you know this?

Not at all

Perfectly

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

1. vasoactive intestinal peptide (VIP), 2. adenosine triphosphate (ATP), 3. nitric oxide (NO), 4. calcitonin gene-related peptide (CGRP), 5. and enteric excitatory neurotransmitters such as substance P (SP) 6. 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.

1. Sympathetic inhibitory reflexes 2. Inflammatory cell influx

What are the primary methods of action of lidocaine in reducing POI?

1. Reduces inflammation 2. Stabilizes cell permeability 3. 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

1. Metaclopramide 2. Cisapride 3. Mosapride 4. 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.

1. Endotoxemia 2. 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?

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