GI/Liver Flashcards
When can liberal fasting guidelines be used?
In healthy patients
How soon before surgery can a patient have a sip of water or oral liquid medication?
Up to 1 hour before surgery
People who are aspiration risks
Age extremes (70) Ascites Collagen vascular diseases Metabolic disorders (DM, hypothyroid, ESRD) Mechanical obstruction Prematurity Pregnancy Neurologic diseases
People with greatest aspiration risk
Pregnant
Morbidy obese
Hiatal hernia
Pre-op anxiety
Medications for aspiration prophylaxis
Anxiolytics
H2 receptor antagonists
Sodium citrate (Bicitra)– acts as a buffer
Metoclopramide (Reglan) - increase gastric motility and increases sphincter tone
Omeprazole (Prilosec)– will decrease acidity
H2 Antagonist that gives the best result
Famotodine (Pepcid)
Examples of H2 antagonists
Cimetidine (Tagamet)
Ranitidine (Zantac)
Famotodine (Pepcid)
How do H2 antagonists work?
Reduce acid secretion by competitively binding to H2 receptors on parietal cells.
When should H2 antagonists be given?
Night before surgery and repeated 45-60 minutes before surgery
How does metoclopramide (Reglan) prevent aspiration?
By preventing and alleviating nausea
MOA: Dopamine antagonist which increases lower esophageal sphincter tone and increases gastric emptying
When is metoclopramide (Reglan) contraindicated?
In a bowel obstruction
When do we give meds like H2 blockers, reglan, and bicitra?
If the person has risk factors for aspiration**
We do not give these meds to patients routinely
When before surgery to you give bicitra?
15 minutes before surgery, and it lasts 1-3 hours.
Increases gastric volume and can cause nausea.
When would we do Sellick’s maneuver?
During RSI (for someone at high risk of aspiration and we can’t do an awake intubation)
Complications of Sellick’s maneuver
Esophageal rupture and cricoid ring fracture
How to perform Sellick’s maneuver
Apply light downward and cephalad pressure (10N) in the awake pressure, and increase pressure as the patient drifts to sleep (20-44N).
Risk factors for aspiration pneumonitis (Mendelson Syndrome)
Gastric volume > .4mL/kg (about 25mL for a 70kg patient)
Gastric pH < 2.5
Severity of aspiration pneumonitis depends on
pH
Volume
Contents of the gastric material aspirated
S/S of aspiration pneumonitis
Resp distress with bronchospasm
Dyspnea
Cyanosis
Tachycardia
Why does Barrett’s esophagus place a person at risk for aspiration?
Because the esophagus becomes less functional, causing dysphagia. Person also obviously has very bad GERD, as this is what caused the disease in the first place.
S/S of hiatal hernia
Retro-sternal discomfort
Burning after meals
Where does peptic ulcer disease most commonly occur?
Antrum of stomach
or
Duodenal bulb
Causes/risk factors for peptic ulcers
Also s/s of peptic ulcers
H. Pylori
Age 45-60
Chronic NSAID use
Steroid use
S/S: Epigastric pain Vomiting Hematemesis or melena in acute hemorrhage Perforation Abdominal tenderness/rigidity
S/S of malabsorption syndromes
Unexplained weight loss**** Diarrhea Steatorrhea Vit. K deficiency Bleeding dyscrasias Anemia Fatigue Edema/ascites
Differences between Crohn’s and UC
Crohn’s
- Vit/mineral deficiencies (B12, mag, folic acid, zinc, iron, and potassium)
- protein loss (decreased serum albumin)
- anemia
UC
- Intermittent blood diarrhea (hooray!)
- fever/malaise
- Abd pain
- Risk of colon CA
What is carcinoid syndrome?
Carcinoid tumors (which release hormones), arising from the appendix, pancreas, or bronchi, secrete substances into the GI tract and systemic circulation, causing an array of symptoms.
S/S: Flushing Diarrhea Bronchospasm Dyspnea Hypo/hypertenion Orthostatic hypotension) Palpitations
Substances released by carcinoid tumors in carcinoid syndrome
Bradykinin
Histamine
Serotonin
Dopamine
Malnutrition is associated with these complications
Prolonged hospital stay
Wound infection/abcess
Resp failure
Death
Albumin level less than ___ in the general surgical population is indicative of malnutrition
3.5
Also weight loss greater than 10% in 6 months is also indicative of malnutrition
Albumin level less than ___ is a major predictor of morbidity
2.1
The liver is a reservoir of blood representing ___-___% of total blood volume
10-15%
Two scoring methods of liver insufficiency
MELD Score
Child-Turcotte-Pugh Score
MELD Score
For ESLD
Looks at Bilirubin, creat, INR, and if you’re on dialysis)
Child-Turcotte-Pugh Score
Looks at: Bilirubin Encephalopathy Albumin Ascites PT/INR Primary biliary cirrhosis
5-nucleotidase
A lab more specific to the biliary tract
Which liver lab can individually test liver function?
None of them! They need to be looked at together and with the patient’s condition in general
Why does cholestatic disease causing bleeding problems?
Bile salt must be secreted into the GI tract for vit K absorption. Lack of vitamin K causes a deficiency of clotting factors dependent on Vit K for synthesis.
How do you treat bleeding in someone with cholestatic disease?
Give Vit K
Give FFP if emergency surgery
Expected blood flow findings in cholestatic disease
Increased portal venous pressure and decreased flow
Peripheral vasodilation
Increased CO
This is the most common blood borne infection in the US
Hep C
Drug for Hep B
Interferon
Drugs for Hep C
Interferon
Ribavirin
Non-Alcoholic Fatty Liver Disease is defined as fat accumulation exceeding __% and can lead to ____
5%
cirrhosis
(the fat causes a degree of hapatocyte necrosis, accumulating inflammatory cells and causing cirrhosis)
Risk factors for non-alcoholic fatty liver disease
Obesity and NIDDM
Non-alcoholic fatty liver disease is asymptomatic but the person will have elevated ____
liver enzymes (AST/ALT)
What can reverse elevated liver enzymes in non-alcoholic fatty liver disease
Weight loss (even as much as only 5 pounds)
An alcoholic may become tremulous __-__ hours after their last drink
6-8 hours
Hallucinations and grand mal serizures may occur __ hours after ETOH withdrawal.
24 hours
How do you treat DTs?
Benzodiazepines
most of our anesthetics will abate most of the s/s of alcohol withdrawal
Cirrhosis is most commonly caused by
Alcoholism, Hep C, and fatty liver disease
CV changes with cirrhosis
Low SVR and high CO
(sepsis-like)
Pulmonary vessels dilate, but then become stiff, causing R heart failure
S/S of cirrhosis
Portal HTN Esophageal varices Ascites and edema Coagulation disorders Hepatic encephalopathy Endocrine disorders Intrapulmonary shunting and V:Q mismatch Hypoxemia due to intra-pulmonary vascular dilations
In liver disease, you have problems with these phases of clotting
Hemostasis
Coagulation
Fibrinolysis
(all three stages!)
These clotting factors are reduced in liver failure
2, 5, 7, 9, 10
Abnormal fibrinogen present
PT/INR are elevated
Pts have thrombocytopenia
Why are platelets fucked up in liver disease?
Normally, the liver makes thrombopoietin, which results in the formation of megakaryocytes in the BM. Also, toxins build up in the bleed, messing with plt function.
End result is decreased plts, fucked up plts, and increased bleeding time.
Vitamin K is needed for the synthesis of
Factors 2, 7, 9, & 10
Proteins C&S
Who develops Vit K deficiency?
People with: TPN Biliary obstruction Pancreatic insufficiency Malabsorption GI obstruction Rapid GI transit
These coag levels will increase due to Vit K deficiency
PT/PTT
What are coumadin and heparin used for?
Coumadin
- DVT, PE, A-fib, prosthetic valves, and MI
Heparin
- anti-coagulation for vascular cases and cardio-pulmonary bypass (CPD)
How does coumadin work?
It competes with binding sites for Vit K in the liver, resulting in the decrease of Vit-K dependent clotting factors (2,7,9,10)
How does heparin work?
Interacting with anti-thrombin III (Factor Xa) and Thrombin (factor IIa)
Normal prothrombin time (PT)
10-12 sec
Tests factors 1, 2, 5, 7, 10
Normal bleeding time
3-10 minutes (tests platelet function)
Normal PTT
25-35 seconds
Tests factors 1, 2, 5, 7, 9, 10, 11, 12
Treatments for Barrett’s esophagus
H2 Blockers
PPIs
Nissen Fundoplication
Peptic ulcers and bleeding
80% stop on their own
10% will die
Rebleeding will increase mortality 10x
Accounts for 5% of ED admissions
Gastric ulcer and peptic ulcer s/s
Gastric:
- Pain
- Anorexia
- Weight loss
- Metabolic derangements
Peptic:
- Epigastric pain
- Vomiting
- Hematemesis or melena
- Perforation
- Abdominal tenderness/rigidity
Aspiration pneumonitis is also called
Mendelson Syndrome
We see a lot of malabsorption syndromes following this type of surgery
Gastric bypass
Autoimmune hepatitis is treated with
Corticosteroids and AZT
Left untreated, fatty liver disease can lead to
cirrhosis
Usually, a ___% increase in Creatinine indicates a corresponding decrease in GFR
50%
