Flashcards in Gen Surg Deck (144):
What percentage of body weight does blood account for in an adult?
What is normal daily water loss through urine in an adult?
1200mL - 1500mL
After primary closure when should the dressing be removed from wound?
Post op day 2 - pt can take shower after post op day 2.
What reverses the deleterious effects of steroids on wound healing?
How can you tell if the pleura is sealing off a chest tube?
Check for Tidling - Take Pleuravac off suction and look at water seal chamber: should be moving w respiration
pleura blocking = decreased/cease in tidling
How do you determine diameter from
2. Gauge size
1. Divide by pi (3.14)
2. 14 gauge = 1/14 of an inch
What is Calot's triangle
Area bordered by
Common hepatic duct
what separates R and L lobes of liver
-Line drawn from IVC just left of the gallbladder fossa
A triangle where more that 90% of gastrinomas are located? borders?
1. Jxn of second and third portions of the duodenum
2. cystic duct
3. Pancreatic neck
What is the vein that overlies the pylorus?
Vein of Mayo
What are layers of the abominal wall?
2. Campers fascia (debatable)
3. Scarpa's fascia, then more fat
4. External oblique
5. Internal oblique
6. Transversus abdominis
what is the common maintenance fluid in an adult?
adult: D5 1/2 NS w 20 mEq KCl/L
ped: D5 1/4 NS w 20 mEq KCl/L
How is 24 hr maintenance fluid calculated?
100 mL/kg for first 10 kg
50 mL/kg for next 10 kg
20 mL/kg for every kg over 20kg
What is the minimal urine output for an adult on maintenance IV?
when should aspirin be discontinued preoperatively
1 week (platelets live 7 to 10 days)
--clinical judgement for stroke or MI pt
Which abx is associated w cholestasis?
- can lead to cholestatic hepatitis
How fast should you lower the sodium level in hypernatremia?
What is the major complication of lowering sodium too fast?
less than 12 mEq/L per day
major complication: Seizures (correcting HYPOnatremia too fast causes Central pontine myelinolysis)
What are signs of Central Pontine myelinolysis
2. Spastic Quadriplegia
3. Horizontal gaze paralylsis
What are causes of Hypercalcemia?
Calcium supplement IV
Hyperparathyroidism (primary, tertiary)
Immobility, Iatrogenic (thiazide)
Mets, Milk alkali syndrome
Paget's dz (usually normal levels of Ca)
Excess Vit D
Excess Vit A
What are ECG findings of hypercalcmia
Shortened PR, QT
What is the acute treatment of hypercalcemic crisis?
Volume expansion w NS
diuresis w Furosemide (Not thiazides)
What are surgical causes of Hypocalcemia?
Short bowel syndrome
Vit D deficiency
what are ECG findings of Hypocalcemia
Prolonged QT and ST syndrome
peaked T-waves are possible (like hyperkalemia)
What platelet count is a/w spontaneous bleeding?
What should the count be before surgery?
Spontaneous bleeding = <20,000
before surgery >50,000
How is myoglobinuria treated?
Hydration w IV fluids
Alkalization of urine w IV Bicarb
How is TBSA calcuated in adults for burns?
Each Upper Limb = 9%
Each Lower Limb = 18%
Ant + Post Trunk Each = 18%
Head + Neck = 9%
Genitalia = 1%
How is TBSA calculated in children for burns?
Ant + Post Trunk Each = 18%
Each Upper limb = 9%
Each Lower Limb = 14%
Genitalia = 1%
What is the Parkland formula?
Estimated volume of crystalloid needed for the INITIAL resuscitation of burn patient
V = TBSA(%) x Weight (kg) x 4
-half given first 8 hrs, rest given next 16 hrs
What type of IVF is contraindicated in burn patient in the first 24 hrs of burn?
glucose containing IVF
-pts serum glucose will be elevated on its own b/c of stress response
What is the fluid management of burn patients?
Initial resuscitation = parkland formula = (TBSA)(kg)(4)
in crystalloid for first 24 hrs
Post 24 hrs = Colloid of D5W + 5% albumin at 0.5 cc/kg/% TBSA of burn
What comprises normal saline?
154 mEq of Cl-
154 mEq of Na+
What comprises D5W?
5% dextrose (50g) in H20
What is the minimal urine output for burn patients? (adults and children)
Adults >0.5 cc/kg/hr
Children 1-2 cc/kg/hr
What kind of GI intervention is often needed in patient with >20% TBSA burn?
--Pts w >20% TBSA burn usually develop a paralytic ileus = vomiting = aspiration risk = pneumonia
What stress prophylaxis must be given to burn patients?
H2 blocker - to prevent burn stress ulcer (Curling's ulcer)
How are minor burns dressed? First + Second degree
Gentle cleaning w nonionic detergent
debride of loose skin, broken blisters
Burn is dressed w topical + sterile dressing
First degree = Keep clean + Neosporin(Neomycin)
Second degree = clean + Silver Sulfadiazene,
--Biobrane (silicone epidermis), or Silverlon
How are major burns dressed?
Cleansing + application of topical Abx (Eschar is avascular = systemic abx will not be delivered)
Eschar is excised withing first week + Split thickness skin grafting
With which abx must serum levels be determined?
What is the use of Ancef in the surgical setting?
Cefazolin - first gen cephalosporin
--Surgical prophylaxis for skin flora
What is the use of Cefoxitin in the surgical setting?
--mixed aerobic/anaerobic infections
--effecve against Bacteroides fragilis
what is the coverage of clindamycin?
Strong against Gram negative Anaerobe (ie B. fragilis)
Adequate gram positive activity
What is the coverage of Gentamicin? notable features?
--gram negative bacteria,
-got to monitor blood peak/trough levels
What is the coverage of metronidazole?
-Serious anaerobic infections (diverticulitis)
--pts should abstain from alcohol during therapy
What is the common use for nafcillin?
Antistaphylococcal penicillin commonly used for cellulitis
What is the "stress dose" for steroids?
100 mg of hydrocortisone IV every 8 hrs then taper (adults)
What are the boundaries of the axilla for LN dissection in breast cancer?
Superior: Axillary V
Posterior: Long thoracic N
Lateral: Latissimus dorsi
Medial: Lat, Deep, or Med to Pec minor depending on level of nodes taken
What 4 Nerves should the surgeon be aware of during axillary dissection?
1. LONG THORACIC N.
2. THORACODORSAL N.
3. Medial pectoral N
4. Lateral pectoral N
What is the preoperative staging workup in a patient with breast cancer?
1. Bilateral mammogram
2. CXR (check for lung mets)
3. LFTs (check for liver mets)
4. Serum calcium level, alkaline phosphatase
---check for bone mets/"bone pain" = bone scan
5. Other tests depending on sx (ie head CT if pt has focal neuro deficit)
what are indications for modified radical postmastectomy radiation therapy?
1. >4 lymph nodes
2. Chest wall involvement by tumor
What breast tumors are candidates for lumpectomy and radiation?
Stage I and Stage II (tumors <5cm)
Where are drains placed in a modified radical mastectomy?
When are they removed?
2. Chest wall (breast bed)
removed when drainage <30cc/day or POD 14 (which ever comes first)
What type of chemotherapy is usually used for breast Ca?
1. CMF (Cyclophosphamide, Methotrexate, 5-FU)
2. CAF (Cyclophosphamide, Adriamycin, 5-FU
What make a breast tumor "High risk"
1. >2cm in size
2. Lymphatic/vascular invasion
3. High nuclear grade
4. S phase( high)
5. ER negative
What are mammmographic findings of DCIS? how is dx made?
dx'd w core or open biopsy
what is thrombophlebitis of superficial breast veins called?
What is the dx modality of fibrocystic dz?
dx: exam, hx, aspirated cysts (straw-colored, green fluid)
tx: Stop caffeine, NSAIDs, Vit E
danazol, OCP as last resort
What prophylactic measures can be taken for DVT/PE?
1. LMWH (Lovenox) 40 mg SQ QD or 30 mg SQ BID
2. SQ heparine (5000 units/8 hrs) - start POST op
+ early ambulation
What do you do of pt has high NGT output?
Check abdominal xray:
if NGT in duodenum, pull back into stomach
what is short bowel syndrome?
Malabsorption/diarrhea from extensive bowel resection
(approx <120 cm small bowel remaining)
Tx: TPN early, small meals chronically
When can a pt be fed through a J tube?
12-24 post op hrs (Small bowel recovers from ileus first)
--then stomach, then colon.
when do post operative MI's usually occur? How do they present usually?
Often w/o chest pain, Dyspnea (new onset CHF), Dysrhythmia
2/3 preset on POD 2-5
What is the formula for FENa?
"YOU NEED PEE" = U-N-P
(UNa x PCr)/(UCr x PNa)
With massive bladder distention from retention, how much urine can you drain immediately?
Most would clamp after 1 L then drain rest over time to avoid vasovagal reaction
Why give supplemental oxygej to a patient w a pneumothorax?
Pneumothorax is almost completely nitrogen = increasing oxygen in alveoli increases nitrogen gradient = faster absorption of the pneumothorax
what is the normal daily dietary requirement for adults:
1. 1 g/kg/day
2. 30 kcal/kg/day
what is the caloric conten of the following substances:
1. fat = 9 kcal/g
2. protein = 4 kcal/g
3. carbohydrate = 4 kcal/g
what is respiratory quotient (RQ)?
what is normal?
how do you decrease RQ?
RQ = ratio of CO2 produced to O2 consumed
normal = 0.8
Decrease RQ = more fat, less carbohydrates
--ie in a patient whom CO2 retention is a concern
What is the color of bile usually in chronic cholecystitis?
What is it called? what does it imply
white/clear bile fluid = Hydrops
--implies severe liver damage, bad prognosis.
What is refeeding syndrome?
Decreased serum: K, Mg, PO3 after refeeding a starving pt
What is the major nutrient of the small bowel?
What is the major nutrient of the colon?
Butyrate and other short chain fatty acids
What is the best parameter to check nutritional status?
what are other labs?
Best = prealbumin (T1/2 is 2-3 days) = acute changes in nutrition status
Albumin - Chronic determination
What are the classes of Hypovolemic shock? (volume lost, sx)
Class I: <15%, 750cc, mild anxiety, normal vitals
Class II: 15-30%, 750-1500cc, normal SBP, decreased pulse pressure, tachycardia/pnea
Class III: 30-40%, 1500-2000, DECREASED SBP, HR >120, RR > 35)
Class IV: >40%, >2000cc, decrease SBP, HR >140, RR> 35
Decrease pulse pressure b/c vasoconstriction elevated DBP
what are associated lab findings of septic shock? (early, late)
Early: hyperglycemia, glycosuria, respiratory alkalosis, hemoconcentration, leukopenia
Late: leukocytosis, acidosis, elevated lactic acid
what is mendelson's syndrome?
Chemical pneumonitis secondary to aspiration of stomach contents
What are signs of central line infection? what infusion increases risk of central line infection?
mental status change
tachycardia - shock
pus, erythema at central line site
Hyperal (TPN) - increase risk of central line infection
What is a "complete" post op fever work up?
Physical exam (look at wound)
What are some causes of post operative fevers before 24 hrs?
2. b-hemolytic streptococcal or clostridial wound infections
3. Anastomotic leak
what treatment provides protection from
1. ETOH withdrawal
2. Wernicke's encephalopathy
1. Chlordiazepoxide (Librium)
2. Rally Pack aka Banana Bag (Thiamine, folate, magnesium)
What C-spine XR views are used to rule out bony injury?
AP, lateral, Open mouth odontoid views
What are rare physical findings that are possible with pancreatitis?
Cullens - periumbilical ecchymosis
Grey turner's sign
Retroperitoneal Hemorrhagic pancreatitis
why does a cholecystectomy sometimes relieve reflux symptoms
CCK slows gastric motility
what are the normal calibers of the small bowel, transverse colon, cecum?
3, 6, 9 rule
Small bowel <3cm
Transverse colon <6cm
What is the rule of 3s for the small bowel?
1. bowel wall should be less than 3 mm thick
2. bowel folds should be less than 3 mm thick
3. bowel diameter should be less than 3 cm wide
What can simulate free air on upright x-ray?
Chilaiditi's sign - Transverse colon over the liver
What is the normal diameter of the common bile duct WITH gallbladder present?
<4mm until age 40, then add 1 mm per decade (ie 7 mm at age 70)
what is the normal common bile duct diameter after removal of the gallbladder?
8 to 10 mm
What are contraindications of the depolarizing agent succinylcholine?
Increased intracranial pressure
Why doesnt lidocaine work in an abscess?
Lidocaine does not work in an acidic environment
--Lidocaine is acidic, can add sodium bicarbonate to decrease burning sensation
What are some contraindications to nitrous oxide?
Nitrous oxide is poorly soluble in serum - expands into any air-filled body pockets
--avoid in pts w:
Middle ear occlusions
Small bowel obstruction
What is a fear side effect of bupivacaine
Cardiac dysrhythmia after intravascular injection - leads to fatal refractory dysrhythmia
What are side effects of morphine? alternatives (situations)?
2. respiratory failure
3. hypotension (histamine release)
4. SPASM OF SPHINCTER OF ODDI
--Use DEMEROL: pancreatitis and biliary surgery
5. Decreased cough reflex
What are side effects of Demerol? Contraindication medication?
--MAOi - contraindication to Demerol
side fx: Tachycardia, Seizures (caused by metabolite, Normeperidine)
What must remain in place until AFTER epidural catheter is removed?
Foley Cath - if removed before, can cause urinary retention
what are early signs of lidocaine toxicity?
large overdose sx?
large overdose: Seizures, coma, respiratory arrest, Loss of consciousness, Apnea
What is a venous stasis ulcer?
Skin ulceration on MEDIAL MALLEOLUS caused by venous stasis of a lower extremity
What is a Dieulafoy's ulcer?
Pinpoint gastric mucosal defect bleeding from underlying arterial vessel malformation
What are the 3 most common cancers in women?
lung is most common cause of death
What are the 3 most common cancers in Men?
lung is most common cause of death
What is a an mucosal ulcer seen in Crohn's disease called?
what stomach cells produce bicarbonate mucus?
Mucous neck cells
Where are most of the bile acids reabsorbed in the gut?
What are inhibitors of gallbladder emptying?
Where is calcium absorbed?
Where is iron absorbed?
What are the main constituents of bile?
Which electrolytes does the colon actively absorb?
Which electrolytes does the colon actively and passively secrete? implications?
-Diarrhea causes normal anion gap acidosis
What is the blood supply to the liver?
75% - Portal V - rich in digestion products
25% - Hepatic A - rich in O2
each provide 50% of O2
What conditions can mask abdominal pain?
Steroids - masks inflammation symptoms
What are lab test ordered to evaluate a patient with an acute abdomen
CBC w differential
HCG in women
How is free air ruled out in a patient that cannot stand?
Left lateral decubitus
--free air collects over the liver
When can appendicitis present with pain in RUQ?
How does gastroenteritis present classically?
Pain usually AFTER vomiting
What endocrine problems can cause abdominal pain?
What is the glycemic control goal in ICU patients?
-decreased risk of infection (Nice Sugar study)
--study showed control <110 had more hypoglycemic events
What is the cutoff point before blood transfusion
normal pt: <7Hb
CHF pt: <10 Hb
Actively bleeding pt: < 9Hb
What are U/S findings a/w acute cholecystitis?
1. Gallstones impacted stone in gallbladder neck
2. thickened gallbladder wall (>3mm)
3. Distended Gall bladder (>4cm A-P)
4. Pericholecystic fluid
What level of total serum bilirubin does one start to get jaundice?
where does jaundice first appear on the body?
Greater than 2.5mg/dL
--first appears under the tongue
What causes itching in obstructive jaundice?
Bile salts in the dermis
What is a cholangiocarcinoma at the junction of the right and left hepatic ducts?
Klatskin tumor - Adenocarcinoma
What are indications for cholecystectomy in the asymptomatic cholelithiasis patients?
1. Sickle-cell disease
2. Calcified gallbladder (porcelain gallbladder)
3. The patient is a child
4. Heart and lung transplant pts b/c morbidity of acute cholecystitis is severe
What are the mucosal folds at the gallbladder/cystic duct junction called?
Valves of Heister
What is referred right subscapular pain of biliary colic called?
What is it called when a stone is impacted in the gallbladder neck or cystic duct compresses the common hepatic duct resulting in bile duct obstruction and jaundice?
Type I - compression of hepatic by stone
Type II - Cholecystocholedochal fistula from stone erosion into hepatic duct
Gallstone impaction in pylorus or duodenum resulting in symptoms of gastric outlet obstruction
--gallstone ileus from cholecystenteric fistula
what medical treatment can be effective for cholesterol gallstones?
Chenodeoxycholic acid - reduces the ratio of cholesterol to bile salt
--use for small <10mm noncalcified cholesterol stones
what type of surgery is usually performed for an acute case of diverticulitis w a complication (perforation, obstruction)
Hartmann's procedure: resection of involved segment w end colostomy - reanastamosis of colon usually after 2-3 postoperative months.
When is it safe to get a colonoscopy or barium enema/sigmoidoscopy after flare up of diverticulitis?
6 weeks after inflammation resolves to rule out colon cancer (risk of perforation)
Most common fistula w diverticulitis?
Colovesical fistula (to bladder)
What are contents of the inguinal canal?
1. Spermatic cord (panpiniform plexus, Vas deferens, cremasteric fibers, Testicular A, genital branch of genitofemoral N.)
2. Ilioinguinal N
What is a hernia called where the hernia sac contains the appendix?
What is a hernia called where the hernia sac contains a Meckel diverticulum??
What is the approximate daily insensible fluid loss in adults?
(skin - 75%, respiratory exchange - 25%)
what are cardiovascular effects of a pneumoperitoneum during laparoscopic surgery?
CVP, PCWP - Elevated
What is a possible cause of post laparoscopic surgery shoulder pain?
Referred pain from CO2 on diaphragm
What are indications for emergent thoracotomy for hemothorax?
1. >1500 cc of blood on initial placement of chest tube
2. Persistent > 200 cc of bleeding via chest tube per hour x 4 hours
What is the GCS score for a patient in a coma?
GCS less than or equal to 8
What must be documented in a rectal exam in the setting of a trauma assessment?
1. Sphincter tone - spinal cord injury
2. Presence of blood - colon/rectal injury
3. Prostate position - urethral injury
What are the common trauma labs?
1. CBC - hematocrit with be normal (no time to equilibrate)
5. Lactic acid
7. Type and cross match
How is the anatomy of neck trauma defined?
Zone III: Angle of mandible and up
Zone II: Angle of mandible to cricoid cartilage
Zone I: Below cricoid cartilage
How much blood can be lost into the thigh with a closed femur fracture?
1.5 L of blood
what intraabdominal injuries are associated with seatbelt use?
small bowel injuries