Liver and GI Flashcards
NPO guidelines
In “healthy patients” liberal fasting guidelines can be followed
No chewing gum or candy after midnight
Clear liquids up to 2 hours before OR
Breast milk up to 4 hours before OR
Light meal, milk, formula up to 6 hours before OR
Sip of water or liquid pre-med up to 1 hour before OR
Who are aspiration risks?
Age extremes 70 yr Ascites (ESLD) Collagen vascular disease, metabolic disorders (Diabetes obesity, ESRD, hypothryoid) Hiatal Hernia/GERD/Esophageal surgery Mechanical obstruction (pyloric stenosis, intestinal obstru) Prematurity Pregnancy Neurologic diseases
Who is at greatest risk for aspiration and what is the treatment
Pregnant morbidly obese hiatal hernia patients Pre-operative anxiety Treatment includes H2 receptor antagonists Sodium Citrate (Bicitra) Metoclopramide Omeprazole
What are the H2 antagonists?
Cimetidine Zantac and Famotodine (best result)
Act as competitive antagonists of histamine binding to H2 receptors on gastric parietal cells
Reduces acid secretion
Best if given the night before and repeated 45-60 minutes before surgery
What is Metoclopramide and how does it work?
dopamine antagonists increases the pressure of the lower esophageal sphincter which speeds gastric emptying
Prevents or alleviates nausea and vomiting
Contraindicated in the presence of an obstruction
How dies Sodium Citrate work?
Non-particulate antacid
Customary dose of 30 mls to raise gastric ph
Increases gastric volume
Give 15 minutes before surgery and lasts 1-3 hours
What is Mendelson Syndrome and how does it manifest?
Aspiration Pneuomitis Characterized according to pH Volume Gastric material aspirated Risk factors for aspiration sequelae include Gastric volume of 0.4ml/kg (25ml/70kg) pH less than 2.5 Manifests as resp distress with bronchospasm cyanosis, tachycardia and dyspnea from irritating action of hydrochloric acid and particulate material which are damaging to the lungs
What are the s/s of Barrett’s Esophagus and what is the treatment?
H2 Blockers Proton Pump Inhibitors Nissen fundoplication Signs & Symptoms Dysphagia Reflux Esophagitis Retrosternal pain or heartburn LES dystonia Weight loss
What is a Hiatal Hernia and s/s?
Protrusion of a portion of the stomach through the hiatus of the diaphragm upward into the thoracic cavity
Surgical repair may be recommended
Signs & Symptoms: Retro-sternal discomfort, Burning after meals
Who is at risk for PUD?
Men and Women age 45-60 Chronic use of NSAIDS ETOH Steroids Epigatric pain Vomiting Hematemesis or melena (this may be acute hemorrhage) Abdominal tenderness and rigidity Perforation
What is PUD and treatment?
Ulcerations in the GI mucosa
Most commonly the duodenal bulb or antrum of stomach
H. Pylori –Cause
Treatment: H2 antagonists Proton pump inhibitors Antimicrobial therapy Antacids
S/S of Gastric Ulcers?
Pain
Anorexia
Weight loss
Metabolic derangements
What are Malabsorption Syndromes?
Clinically significance deficits in mineral, vitamins and electrolytes Small Bowel perforation or obstruction Small Intestine Celiac Sprue Fat Malabsorption Protein Malabsorption
What are your Malabsorption Syndromes s/s?
Signs & Symptoms Unexplained wt. loss Steatorrhea Diarrhea Anemia Fatigue Deficiency in Vitamin K Bleeding dyscrasia Edema/ascites
What is Chron’s Disease?
Distal ileum and large colon
Deficiency in magnesium, B12, Phosphorus, Folic acid, Zinc, Iron potassium,
Protein Loss decreased plasma albumin
Anemia
What is Ulcerative Colitis?
Distal Colon and rectum Intermittent bloody diarrhea Fever/ malaise anorexia/wt. loss Abdominal pain Associated with risk of colon cancer
What is Carcinoid Syndrome?
Site of origin is in the GI tract (appendix, pancreas or bronchi)
Most symptoms are produced by the effects of hormones and substances secreted in the GI tract and systemic circulation
Bradykinin
Histamine
Serotonin
Dopamine
What are the S/S of Carcinoid Syndrome?
Cutaneous flushing Diarrhea Palpitations Bronchospasm dyspnea Hypotension Hypertension Orthostasis Pre-op test are guided by physical findings
What are general preoperative considerations for the GI Patient?
Airway management and prevention of aspiration Fluid and Electrolyte Balance Skin Peripheral circulation Heart rate Blood pressure Urine output Kidney function Orthostasis
Useful Labs and Monitoring?
Useful Lab values: Hematocrit Serum electrolytes BUN Serum albumin Monitoring : Does patient need invasive lines CVP or PAP monitoring Aline
What is malnutrition associated with?
prolonged hospital stay Wound infection Abscess Respiratory failure death
What is the serum albumin level associated with?
Less than 3.5 in the general surgical population is accurate predictor of malnutrition
Less than 2.1 major predictor of morbidity in veterans undergoing non-cardiac surgery
What are the physiologic function of the liver?
Vital reservoir of blood represents 10-15% total blood volume Maintains normal clotting Mediator of endocrine functions Bilirubin excretion Metabolism Synthesis of proteins Immunologic Function Pharmacokinetics
What are the risks factors and symptoms associated with chronic liver disease
History of jaundice, Prior blood transfusions Recreational drugs/Alcohol Current medications includng herbals Family history of jaundice and liver disease Travel history Occupational history ROS: easy bruising, anorexia, weight loss or gain N&V, pain, pruritus, GI bleeding
How do you grade prep liver dysfunction?
MELD Score Child-Turcotte -Pugh Score Encephalopathy Ascites Bilirubin Albumin PT (INR) Primary biliary cirrhosis
What are abs to assess liver function?
AST and ALT Alkaline phosphatase 5’Nucleotidase GGT Serum bilirubin Prothrombin Time Albumin (normal 3.5-5.0 g/dl) Complete CBC Coagulation studies Serum electrolytes and glucose levels Serum ammonia levels Platelet count >100,000 Toxicology
What CV things should you look for or expect?
Increased levels of endogenous vasodilators such as vasoactive intestinal peptide High cardiac output Decreased systemic vascular resistance Hyperdynamic circulatory state Arteriovenous shunting Portal hypertension Pre-operative EKG is warranted
What respiratory and fluid balance things should you look for?
Respiratory:
Ascites impairs the movement of the diaphragm resulting in decreased FRC
Right to left shunting secondary to arterivenous shunting
Fluid balance:
Ascites and edema offer evidence of derangement in fluid status
Correction of volume status with attention to central filling pressures
What is this cholestatic disease?
Cholestatic disease predisposes towards Vitamin K deficiency
Biliary obstruction coagulopathy results from a deficiency of factors dependent on Vitamin K (II,VII, IX, X)
Absorption of Vitamin K depends on Bile Salt excretion into GI tract
Long term biliary obstruction can cause liver dysfunction interfering with protein synthesis
What is the treatment of cholestatic disease?
Treatment is to correct with parental Vitamin K
FFP is necessary if emergent surgery or presence of hepatic injury
Expected findings
Increased peripheral vasodilation
Increased CO
Increased portal venous pressure
Decreased portal venous blood flow
What should the preoperative assessment focus on with the patient with acute or chronic hepatitis?
Preoperative evaluation should focus on signs and symptoms of encephalopathy, bleeding, jaundice ascites, and hemodynamics)
Lab findings
Electrolytes, BUN, creatinine, serum glucose, H/H, liver enzymes, bilirubin, coagulation studies, and abg
What is non-alchoholic fatty liver disease?
Most common cause of chronic liver disease
Fat accumulation in the liver exceeding 5%
Risk factors include NIDDM and obesity
Asymptomatic but elevated liver enzymes (AST & ALT) found on physical exam
Produces some degree of hepatocyte necrosis which promotes the accumulation of inflammatory cells in liver
Leads to cirrhosis
Weight loss (even 5 lbs) can reverse the elevated liver enzymes
Alcoholic liver disease s/s
malaise nausea anorexia Weakness abdominal discomfort hepatomegaly jaundice
Results in:
Steatosis (fatty liver)
Alcoholic hepatitis (precursor Cirrhosis)
Cirrhosis
What are characteristics of DTs
Within 6-8 hours of ETOH withdrawal patient may become tremulous
Alcohol hallucinosis and grand mal seizures occur within 24 hours
DTs usually appear within 72 hours of withdrawal and are preceded by tremulousness, hallucinations or seizures
Treatment is with benzodiazepines
What are s/s of cirrhosis?
Anorexia weakness nausea vomitting abd pain hepatomegaly ascites jaundice spider nevi metabolic encephalopathy Hyperdynamic circulation high CO low PVR Gastroesophageal variceal Intrapulmonary shunting Ventilation Perfusion mismatch Arterial hypoxemia due to Intra-pulmonary vascular dilations (IPVD) Ascites and Edema Coagulation disorders Endocrine disorders Hepatic encephalopathy Portal Hypertension
What are the three abnormalities you have related ti clotting and platelet function?
Hemostasis
Coagulation
Fibrinolysis
What are the coagulation disorders?
Disorders of coagulation rapidly develop in patients with severe liver failure
Factors II, V, VII, IX, X all reduced in liver failure
PT and INR elevated
Thrombocytopenia
Abnormal fibrinogen
What are platelet disorders?
Abnormal platelet function
Decreased platelet function
Increased bleeding time
What are disorders of clotting factors?
Vitamin K deficiency
Coumadin Therapy
Heparin Therapy
Vitamin K helps make what factors?
Vitamin K is necessary for the hepatic synthesis of Factors II, VII, IX, X, and Protein S and Protein C
Vitamin K deficiency develops in what type of patients?
Vitamin K deficiency develops in patients on parenteral nutrition, biliary obstruction, pancreatic insuff, malabsorption, GI obstruction and rapid GI transit
Effects of Vitamin K deficiency include prolonged PT, PTT
