Nursing 2 Lecture

What is the difference between parenteral and enteral nutrition?

1. Parenteral - administration of essential nutrients by IV infusion

2. Enteral -

Why should parenteral nutrition be a last resort? What are the 2 classes?

• Risk of infection from catheter site

• Villous atrophy atrophy of small intestine (possible increase in sepsis risk)

Partial parenteral nutrition (PPN) - nutrition administered peripherally

• Osmolality <600 mOsm/L

• Can only provide a portion of total energy requirements

Total parenteral nutrition (TPN) - nutrition administered centrally

• Very hypertonic solutions that must be administered into a large vein to minimize phlebitis/thrombosis (>1500 mOsm/L)

What does nutritional assessment involve?

• Evaluation of HX

• Physical exam

• Body weight (BW)

• BCS

• Lab data (hypoalbuminemia/anemia, alterations in BUN, cholesterol, creatinine kinase, RBC, and lymphs seen in malnutrition)

What are a few indications for parenteral nutrition?

1. Acute loss of >5% BW or anorexia for >3 days

2. Ileus

3. Pancreatitis

4. Severe injuries preventing enteral nutrition (facial)

What is BER, RER, and MER?

1. BER - basal energy requirements describe the energy that is needed to meet the needs of cells and organs under a stress free, thermoneutral environment, and in a post-absorptive state

2. RER - resting energy requirements accounts for the energy required by the animal in a resting state and includes physiologic influences and assimilation of nutrients

3. MER - maintenance energy requirements encompass all the energy required for maintaining normal BCS in a pet

What are the most common types of feeding tubes?

1. NE/NG - nasoesophageal/nasogastric (liquid diets used, small French)

2. E - esophagostomy (larger French)

3. PEG or G - gastrotomy (larger French)

4. J - jejunostomy (liquid diets used, small French)

What is refeeding syndrome?

Refers to the metabolic derangements that occur with the reintroduction of food after a prolonged period of malnutrition

What are the main electrolytes of concern when it comes to refeeding syndrome?

Phosphorus, potassium, and magnesium

What are some complications w/ refeeding syndrome?

1. Hypophosphatemia - hemolytic anemia

2. Hypomagnesemia - irritability or aggression

3. Hyperinsulinemia - reduced water and sodium excretion

4. Thiamine deficiency - co-factor in carb metabolism, starvation-induced deficiency is exacerbated by carb feeding

What is the difference between vomiting and regurgitation? What is expectoration?

1. Vomiting

• Active process

• From the stomach/intestines

• Involves hypersalivation, nausea, and retching/abdominal effort

• May contain food that is partially digested or not digested, bile, and/or mucous

2. Regurgitation

• Comes from the mouth, pharynx, or esophagus

• Bile is not present and undigested food is present

• Passive process, no abdominal effort

• Indicates esophageal disease/disorder

3. Expectoration

• Comes from the respiratory tract

• Material coughed up at the time of vomiting event

What is the difference between SI and LI diarrhea?

Small intestine

• Near-normal frequency defecation

• Increased appetite w/ weight loss sometimes

• Soft to watery stools, larger in volume

• Usually melena seen (digested blood)

• Neoplasia or malabsorptive or protein losing diseases usually

Large intestine

• Increased frequency in defecation, smaller volume

• Rarely exhibit weight loss or increased appetite

• Watery, mucoid stools with hematochezia

• Tensmus, dyschezia

• Neoplastic, dietary/fiber responsive, parasitic, bacterial, fungal, inflammatory, or secondary to a retrovirus (cats) in nature

What is cachexia?

A condition in which there is weight loss due to the loss of lean body mass and decreased caloric intake

• Differs from starvation in that starvation will cause the body to use fat as energy, cachexia the body uses lean body mass and muscle for energy due to changes that have occurred secondary to influences from chronic disease

Where does the urge to vomit originate? What are the 3 stages of vomiting?

Medullary vomiting center

Stages of vomiting

• Nausea - hypersalivation, vocalization, lip smacking, pawing at the mouth

• Retching/contractions

• Expulsion

What is feline eosinophilic granuloma complex (FEGC)?

• Eosinophilic plaques, linear eosinophilic granulomas, or eosinophilic ulcers “rodent ulcers”

• Maxillary lips most commonly affected

• Diagnosis - biopsy + histopath, generally treated based on HX and PE findings

• TX - control allergies (parasites, food, environment); corticosteroids; pain control; recurrent disease; ± systemic ABX

What is feline gingivitis-stomatitis-pharyngitis complex?

• Painful inflammation of the oral tissues (fauces, gingiva, buccal mucosa, pharyngeal regions)

• Complete work up w/ viral testing is needed

• TX - periodontal management, ABX, anti-inflammatories, analgesics, tooth extraction including all root tips, nutrition

• Guarded prognosis

What is the most common type of oral neoplasia in dogs and cats respectively?

Dogs

• Malignant melanoma

• Very aggressive w/ poor prognosis

Cats

• Squamous cell carcinoma which is invasive to local tissue

• 2nd most common is fibrosarcoma

What is megaesophagus (”Mega-E”)?

• Generalized loss of motor function to esophagus

• Clinical signs = regurgitation, weight loss, coughing, fever, lethargy (fever and coughing can point to aspiration pneumonia)

• Diagnostics - imagining, labs

• Patient care - remove inciting cause ASAP, minimize aspiration, maximize nutrient intake, feed in upright position, use different consistency of food

What are some nutritional highlights for megaesophagus?

Protein

• Imporant for tissue repair and growth

• Stimulates gastrin and gastric acid secretion - increases gastroesophageal sphincter pressure + decreases risk of reflux

High energy density

• May need lower fat if esophagitis present since this can increase risk for gastroesophageal reflux (GER)

• Fat slows gastric emptying and reduces lower esophageal sphincter pressure

Other

• Feed upright and remain upright for 20-30 minutes after eating

• Small, frequent meals

What species is more affected by acute gastritis? What are clinical signs?

• Dogs more affected than cats

• Clinical signs - vomiting is #1, may be hyporexic

• TX - antiemetics, ± fluids, fasting then bland diet for a few days

What species is more affected by chronic gastritis? Clinical signs?

• Cats more affected than dogs

• Clinical signs - vomiting more than 1-2 weeks duration, may experience hyporexia, weight loss, hematemesis, melena

• Biopsy w/ histopath needed for diagnosis and to guide TX

What are 2 of the most common risk factors for gastric ulceration? What is another less common cause?

1. Liver disease - helps clear gastrin and support normal GI mucosal function normally; dysfunction can cause clotting issues

2. TX w/ NSAIDs

• Topical irritant effect and can inhibit prostaglandins

• COX - 1 - involved in production of protective prostaglandins

• COX - 2 - involved in production of inflammatory mediators

• Never use steroids and NSAIDs

CKD

• Uremic toxic can cause GI hemorrhage

• Kidneys excrete 40% of circulating gastrin - decreased in CKD

• Increased gastrin can lead to increased gastric acid secretion

What are the most important nutritional factors when it comes to GI disease?

1. Water - MOST IMPORTANT

• Cold water delays gastric emptying time

2. Electrolytes

• Acute vomiting - mild hypokalemia, hypochlorite a, and either hypernatremia or hyponatremia

3. Protein - not fed in excess

• <30% dry matter for dogs and <40% for cats

• Protein digestion increase gastrin and gastric acid secretion

4. Fat - not fed in excess

• <15% dry matter for dogs and <25% for cats

5. Fiber

• <5% dry matter

• Has been shown to delay gastric emptying

• Feeding - focus on warm, moist, small, frequent meals

What is the definition of diarrhea and what are the 4 main mechanisms?

An abnormal increase in frequency, fluidity, or volume of bowel movements or stools

1. Osmotic - unabsorbed matter stays in intestines and pulls water in by osmosis (poorly digested/absorbed nutrients)

2. Altered mucosal permeability - intestinal lining is damaged/inflamed and becomes “leaky”; fluid, electrolytes, and sometimes protein/blood is lost (severe enteritis)

3. Abnormal GI motility - intestinal contents move too quickly, no time to absorb water or nutrients properly (fat)

4. Secretory diarrhea - intestinal cells actively secrete excessive electrolytes into the lumen, and water follows (some bacterial toxins stimulate chloride secretion)

What are some differences in acute and chronic diarrhea?

Acute

• Most common causes of- diet/indiscriminate eating, parasites, or infectious disease

• Symptoms usually 7-14 days

Chronic

• Common causes - maldigestion of nutrients, non-protein losing malabsorption, and protein-losing malabsorption

• Usually persists weeks to months

What are the 4 main nutritional factors for small bowel diarrhea?

1. High quality protein

2. Fatty acids

• Increasing N-3 fatty acids (EPA and DHA) decreases inflammatory response

3. Digestibility

• Protein digestibility of >87%

• Fat and carb digestibility of >90%

4. Probiotics

• Most bacteria do not survive gastric acid

What are the 6 nutritional factors for large bowel diarrhea?

1. Water - parenteral or enteral

• Most important for patients with acute cases

2. Electrolytes

• Hypokalemia is common - correct w/ fluids

• Diet should include sodium, chloride, and potassium

3. Protein

• High biologic value and digestible

4. Fat

• Low to moderate is typical - higher concentrations can be used if needed for calories

5. Fiber

• VERY IMPORTANT

• Normalizes colonic motility and transit time, buffers toxins, binds excess water, supports growth of normal GI flora, provides fuel for colonocytes, and alters viscosity of GI luminal contents

6. Fatty acids

• May decrease inflammation

What is inflammatory bowel disease and what are the 2 most common types? What are some clinical signs?

Chronic, immune-mediated group of intestinal disorders that can affect both SI and LI

1. Lymphocytic-plasmacytic enteritis (LPE)

• GSD, Shar-pei, purebred cats, basenjis, and lundehunds

• Older animals most common

2. Eosinophilic enteritis (EE)

• GSD, Dobermans, and Rottweilers

• No age predisposition

Clinical signs

• Intermittent or consistent

• Vomiting, diarrhea, ± appetite changes, lethargy, weight loss

What is the gold standard of diagnosis for IBD (inflammatory bowel disease)? What are some nutritional points?

• Gold standard - histopath of biopsy samples (endoscopy vs laparotomy)

• Energy dense food is best, monitor fats, cats can tolerate better

  • Fat: 12-15% in dogs, 15-25% in cats

  • Protein: hypoallergenic diet, high protein digestibility, and novel protein or hydrolysis protein

  • Fiber: moderate levels (7-15%) of insoluble fiber recommended, decreases energy density and digestibility

  • Vitamins: Serum cobalamin (B-12)

What is the most common cause of megacolon and the most affected species?

• Idiopathic cause

  • Can be seen secondary to orthopedic, metabolic, or neurologic pathology

• Cats more likely to be affected than dogs

What are some key differences in nutritional factors for constipation and obstipation?

Constipation

• Water is important, canned pumpkin, moist food, etc

• Increase fiber in diet

  • At least 7% DM of insoluble or mixed fiber

  • Soluble fiber can reduce availability of minerals, do not increase fecal bulk or dilute luminal toxins

Obstipation

• Water is imporant

• Be careful w/ fiber

  • No colonic motility remains

  • Fiber cannot stimulate motility, can contribute to further obstipation

  • Megacolon - no more than 5% DM crude fiber

What are the most common causes of food allergy in cats and dogs respectively? What are some clinical signs? How long must an elimination diet trial be fed?

Cats - fish, beef, and dairy

Dogs - beef, chicken, dairy, wheat, egg, lamb, and soy

1. Clinical signs - pruritis, dermatitis, otitis, pyoderma, vomiting/diarrhea

2. Fed for 6-8 weeks +, then reintroduce ingredients over 7 days if able

What is GDV? Why is it such an emergency? What are some clinical signs?

Gastric dilatation and volvulus - dilation of the stomach plus rotation to abnormal position

• Compression of vena cava - decreased venous return

• Pressure on diaphragm - respiratory distress

• Decreased blood flow through portal vein - decreased preload

• Compromised gastric circulation - ischemia

  • Ischemia - build up of toxic and vasoactive substances

• Tearing of short gastric vessels - hemorrhage

• Possible splenic involvement

• Relieving ischemia during surgery - releases toxins in blood - reperfusion syndrome

Clinical signs

• Acute onset of nonproductive retching, attempting to vomit, salivation, ± abdominal distention and collapse

How is GDV diagnosed and what is the general TX? What is one important tip for catheterization in these cases?

Diagnosis

• Right lateral radiography

  • Double bubble or Smurf hat

  • Tachycardia, tachypnea, bounding pulses, injected mucous membranes collapse, etc

• TX

  • Oxygen

  • Fluids

  • 2 large bore catheters in cephalic/jugular veins - cannot put in the caudal portion of the body since caudal vena cava is compressed, may not reach the heart properly

  • Lidocaine if ventricular arrhythmias present with: >160BPM, arrhythmia is multiform, R on T phenomenon, or if perfusion is affected

  • Pass orogastric tube to empty stomach or place a large bore catheter (trocharization)

What is the general surgical prep for any gastric emergencies?

Surgical prep should extend from the mid-thorax to caudal abdomen

What is intussusception?

When one section of the intestines slides/telescopes inside the adjacent section of intestine

• Can cause obstruction/compromised blood supply

What is AHDS? What are some clinical signs of shock and how is AHDS diagnosed? TX?

Acute hemorrhagic diarrhea syndrome - frank or digested blood in vomit/diarrhea

• Can see signs of shock - hypothermia, poor perfusion, weakness, obtunded

• DX - PCV >60% and relatively low TS (especially albumin), caused by major fluid loss from circulation into the intestinal lumen

• TX - fluids, need to decrease PCV to <55% ASAP, colloids, IV ABX, gastroprotectants

What is peritonitis? What is the most common kind and how is it diagnosed? What is the treatment?

Inflammation of peritoneum - membrane lining abdominal cavity

• Septic peritonitis is most common in dogs and cats (leakage of GI after a perf)

DX

• Cytology of effusion

• Septic peritonitis - intracellular bacteria w/in degenerate neutrophils

• Labs/imaging

TX

• Stabilize - fluids, analgesics, ABX

• Exploratory laparotomy

• Drain post-op

What are some tips concerning sucralfate?

• Works best in acidic environment

  • Give on empty stomach

  • Give at least ½ hour prior to H2 antagonist or antacids

  • Works best in a slurry

  • Separate concurrent medication administration up to 2 hours

How does fat have an effect on the body?

1. Delays gastric emptying

2. Increases gastric acid secretion

3. Increases risk of gastroesophageal reflux

Is early feeding advised in canine pancreatitis cases? How long should there be a fast?

Early feeding is not recommended; nutritional support instituted in 2-3 days

What materials are used for long term use? What constitutes short term use and what materials are best for this?

1. Polyurethane or silicone

2. <10 days; polyvinylchloride or red rubber tubes (become stiff with long term use)

How often should tubing be changed on a syringe pump if being used for parenteral feedings?

Every 24 hours to prevent bacterial growth

How long is needed for a stoma to be formed for a gastrotomy tube?

12 hours before feeding can begin, should be left in place for 7-10 days to allow a permanent stoma to form before removal

When is a jejunostomy tube indicated?

When the upper GI tract must be rested or when decreased pancreatic stimulation is desirable

What main things does plasma provide to a patient?

Coagulation factors, albumin, and globulins

What is reperfusion injury and how can lidocaine and ketamine help?

Tissue damage that happens when blood flow returns to tissues deprived of oxygen

• Oxidative stress/free radicals

• Inflammation - neutrophils activated

• Calcium overload - worsens mitochondrial/cell damage

• Endothelial injury - can cause edema and impaired microcirculation

Lidocaine has anti-inflammatory effects and can reduce neutrophil activation

Ketamine blocks NDMA which discourages excitotoxicity and calcium entry into cells

What are the 3 keys components to reperfusion injuries?

1. Cellular necrosis

2. Micro vascular injury

3. Hemorrhage