DeVirgilio

Question 1

1. Subclavian steal syndrome

2. Leriche syndrome

Answer 1

1. arteriosclerotic plaque in left subclavian artery, proximal to vertebral branching
   when arm is exercised, blood flow in vertebral reverses (Steals blood from posterior circulation) –> Decreased blood to brain –> claudication of arm (numbness, tingling, muscle pain) AND posterior neurologic signs (confusion, dysarthria, blindness, vertigo, ataxia)
   - bruit above clavicle
   - duplex scanning shows reversal
   - tx is bypass surgery
2. Leriche syndrome - occlusion of infrarenal aorta seen in smokers
   - butt and thigh claudication
   - absent femoral pulses
   - impotence
   no ischemic rest pain (limb threatening ischemia) due to collaterals

Question 2

AAA

1. Location
2. Mgmt
3. Signs of rupture vs leak
4. Complications of AAA surgical repair

Answer 2

1. Pulsatile abdominal mass, associated with atherosclerosis, SMOKING, male, older age
   - diabetes is protective
   - usually infrarenal, above aortic bifurcation
   - one-time US for men 65-75 who have ever smoked
   - degeneration of medial layer
2. Mgmt
   3-4 cm - observe
   >5 cm or >1 cm growth/year - elective repair
3. Rupture into left retroperitoneum (IVC is on the right)- abdominal pain, pulsatile abdominal mass, hypotension
   *as opposed to aortic dissection – tearing chest pain radiating to back
   Leak - sudden onset back pain –> retroperitoneal hematoma *needs surgery ASAP
   can stretch ureters and refer pain to testicles
4. Complications - MI!
   - ischemia (IMA) –> ischemic colitis - presents dats after with bloody diarrhea
   - aortoenteric fistula (bw duodenum) - can present months after with brisk GI bleeding
   - erectile dysfunction (sympathetic venous plexus)
   - graft infection (S. aureus, epidermidis)
   - anterior spinal syndrome (Adamkiewicz) - loss of pain/temp, preservation of vibration and proprioception

Question 3

1. P’s of acute arterial occlusion / limb ischemia + what is first affected
2. Diff between AAO and compartment syndrome
3. MC site of atherosclerotic occlusion in lower extremities

Answer 3

1. Acute arterial occlusion - usually emboli from common femoral artery (due to afib), or acute thrombosis (eg of a previous graft), vascular trauma 
Pain
Pulseless
Paresthesia
Paralysis - worst prognosis
Poikilothermia (cold)
Pallor
*do IV heparin / IVF + doppler / CTa then surgery (bypass or embolectomy)

muscle first affected (4 hrs), then nerve (8hrs), fat (13 hrs), skin (24 hrs)

2. compartment syndrome - 5 P’s but pts still have weak pulse (pulse loss is late sign, pain is early)
   normal pressure is 5-10
   needs bedside fasciotomy
3. superficial femoral artery in Hunter’s canal (Adductor canal on middle 1/3 of medial thigh) –> supply calf muscles

Question 4

1. DDx for amaurosis fugax
2. Carotid artery embolus
3. Carotid sheath

Answer 4

1. CRAO, retinal vein occlusion, orthostatic hypotension (diabetics), giant cell, retinal detachment, open angle glaucoma, papilledema, optic neuritis, Carotid artery embolus
2. Carotid artery embolus - suspect with carotid bruit, see Hollenhurst plaques (cholesterol microemboli)
   - CEA for >50% stenosis in symptomatic
   >60% stenosis in asymptomatic
   - otherwise given ASA, statin, clopidogrel
3. Carotid sheath - carotid artery, internal jugular vein, vagus nerve, deep cervical lymph nodes

Question 5

1. PVD/PAD signs
2. arterial vs venous ulcers
3. Medical treatment
4. PAD definition

Answer 5

1. PVD - absent pulses, bruits, decreased hair growth, muscle atrophy, thick toenails, tissue necrosis/ulcers, prolonged capillary refill time

2A. arterial ulcers - punched out ulcers with demarcated borders, on tibia toes (sites of pressure)
- ischemia –> shiny skin, absent pulses, hair loss
- dependency, claudication
B. venous stasis - shallow ulcer with fibrinous base, irregular, on medial malleolus
- due to chronic venous insufficiency –> stasis dermatitis, limb heaviness, varicose veins, dependent edema, can lead to SSC (marjolin ulcer)

3. PACE
   Pentoxifylline (PDE inhibitor that deforms RBCs and makes them more flexible)
   Aspirin (inhibits COX –> platelet aggregation)
   Cessation of smoking
   Exercise
4. PAD = ABI < 0.9
   <0.8 - claudication –> medical management
   <0.4 - ischemic rest pain - red foot, pain relieved by dangling feet (dependency) –> surgery

Question 6

Causes and symptoms of:

1. Mesenteric ischemia - chronic
2. Acute mesenteric ischemia
3. ischemic colitis
4. Median arcuate ligament syndrome

Answer 6

1. Chronic intestinal ischemia from long-term occlusion of intestinal (mesenteric) arteries due to atherosclerosis
   Sx - weight loss, food fear, heme occult +, n/v
   - can hear abdominal bruit
   - pts with atherosclerosis, embolic source (afib, infective endocarditis)
   - do duplex, angiography
2. AMI - acute onset due to emboli from heart (Due to MI, Afib, endocarditis) to SMA or thrombus of long-standing atherosclerotic plaque
   - associated with digitalis
   - surgical emergency! do angiography then embolectomy
   - high WBC, metabolic acidosis, high amylase and Hb
   - pain out of proportion to physical exam, no peritoneal signs until necrosis, vomiting/diarrhea
3. Ischemic colitis - pts with atherosclerosis and low blood flow –> watershed areas (eg splenic flexure) affected
   - blood diarrhea! WBC, lactic acidosis
   - ulcerations and cyanotic mucosa with sharp transition from affected to unaffected
   - can be due to AAA repair –> loss of IMA –> left and sigmoid colon affected
4. Median arcuate ligament syndrome - composed of fibers from diaphragm hiatus, compresses celiac artery and nerves

Question 7

Splenic aneurysm

1. Causes
2. Risk factors

Popliteal aneurysm

Answer 7

Splenic aneurysm
1. Causes
women - medial dysplasia
men - atherosclerosis
2. Risk factors - pregnancy

Popliteal aneurysm - repair if >2cm
75% have other aneurysms, 50% in aorta

Question 8

Postop fever causes and timeline

Answer 8

Wind - POD 1-2 - PNA, aspiration, due to atelectasis
Water - POD 3-5 - UTI
Wound - POD 5-7 - SSI, abscess
Walking - POD 5+ - DVT, PE
Wonder - any time - drug reactions, IV line infections

Question 9

Abdominal trauma

1. Penetrating eg GSW
2. Stab
3. Blunt

Answer 9

Abdominal trauma
1. Penetrating GSW - exlap + tetanus ppx

2. Stab -
   - if stable - digital examination, FAST or DPL
   - unstable or + FAST - exlap
3. Blunt
   - peritoneal –> ex lap
   - Hemodynamically unstable:
   FAST (+) –> ex lap
   FAST (-) –> DPL

• hemodynamically stable (systolic > 90) –> FAST
  i. FAST positive or FAST normal but high risk features (AMS, pelvic fracture, anemia, local tenderness) –> CT A/P
  ii. FAST negative - repeat in 30 min, serial abdominal exams
  iii. FAST unequivocal – diagnostic peritoneal lavage
• 2L fluid challenge, if no response then 1:1 PRBC:FFP (massive transfusion protocol - give blood early to prevent dilutional coagulopathy) –> need to ID and stop bleeding
• any penetrating injury below the nipples has potential to involve abdomen via diaphragm

Question 10

Differential for groin mass

Answer 10

MINT *most commonly enlarged lymph nodes

Malformation - hernias, undescended testicle

Infectious/inflammatory - mono, abscess, lymphogranuloma venereum, LAD - reactive, diffuse nontender (TB, sarcoid)

Neoplastic- LAD - local nontender (mets from melanoma anal or genital cancer), lymphoma

Traumatic - hematoma, femoral aneurysm

Question 11

1. Define sentinal node
2. When do you do axillary node dissection?
3. Compare DCIS and LCIS

Answer 11

1. Sentinel node - first node from which the lymphatics of the breast drain
   remove and determine if cancer has spread
2. ALND - if 2+ sentinel nodes positive or if pt has mastectomy –> used to stage breast cancer
3. DCIS - linear microcalcifications on mammo, comedo central necrosis, IS premalignant higher incident of concurrent + subsequent invasive cancer –> needs to be excised (lumpectomy to negative margins)

LCIS - incidental finding, malignant epithelial cells of lobules; NOT premalignant but 2x risk of concurrent or subsequent invasive cancer later on in either breast, give tamoxifen

*breast ca mets to spine pedicles (bone, lungs, brain, liver)

Question 12

Breast masses

1. Fibroadenomas
2. Cystosarcoma phyllodes
3. Mammary dysplasia
4. Intraductal papilloma

Answer 12

1. Fibroadenomas - young women, firm rubbery mass that moves easily; do FNA or US, remove
2. Cystosarcoma phyllodes - late 20s, growing mass that distorts breast but is not fixed; do core biopsy and remove
3. Mammary dysplasia - in 30s and 40s, b/l tenderness related to menstruation, lumps that come and go
   - do mammo if no lumps, aspirate cysts and if mass persists, do biopsy
4. Intraductal papilloma - 20s to 40s with bloody nipple discharge
   - mammogram, galactogram, surgical resection

Question 13

Things that keep fistulas open

DDx for chest pain

Answer 13

FRIENDS
Foreign body
Radiation 
Inflammation - granulomatous
Epithelialization 
Neoplasm
Distal obstruction
SteroidsChest pain: 

ACS (UA, NSTEMI, STEMI)
Aortic Dissection 
Coronary vasospasm (Prinzmetal)
Pericarditis
PE
Diffuse esophageal spasm 
Esophageal perf
Pneumothorax

Question 14

1. Best conduit for CABG

2. Describe AS and explain why chest pain, dyspnea in aortic stenosis

Answer 14

1. internal mammary coming of left subclavian –> attach to LAD (most commonly affected coronary vessel - changes in V2,3,4) with graft from R saphenous vein
2. AS - midsystolic crescendo-decrescendo murmur heard loudest at right upper sternal border + S4 –> LVH, syncope + angina + dyspnea, pulses parvus et tardus
   A. Chest pain - increased myocardial 02 demand (due to high wall tension, LVH) and decreased diastolic coronary blood flow –> angina
   B. Dyspnea - stiff ventricle requires higher filling pressures to maintain EDV –> increased pulmonary venous pressures and sensation of SOB

Question 15

DDx for adrenal nodule

Workup

Answer 15

Adrenal nodule:

• Cushing’s (hypercortisol) - pituitary adenoma (Cushing disease), iatrogenic, adrenal adenoma, NSCLC
• Conn’s (hyperaldosterone)
• Pheo - 24 hr plasma free metanephrines
• Hyperandrogen
• Benign, nonfunctional adrenocortical adenoma most common
• Adrenocortical carcinoma - if >6cm, hormonally active –> do open adrenalectomy
• Mets (lung, breast, melanoma, lymphoma)

Workup - do NOT biopsy adrenal mases – do biochemical workup

• free urine cortisol, measure ACTH (iatrogenic or adrenal tumor)
• low dose dexamethasone suppression (pituitary e.g. Cushing disease)
• high dose (ectopic e.g. SCLC)

Question 16

1. DDx hypercalcemia
2. Symptoms of Hypercalcemia
3. Primary vs secondary vs tertiary hyperPTH

Answer 16

1. Hypercalcemia:
   immobility, iatrogenic, ca supplementation, primary hyperPTH, hyperthyroid, milk-alkali, paget, addison’s, acromegaly, PTHrP, ZE syndrome, sarcoid, increased vitamin A/D, familial hypocalciuric hypercalcemia
2. (kidney) stones, (aching) bones eg osteitis fibrosa cystica, (abdominal) groans, (psych) overtones e.g. fatigue, impaired memory, depression
3. Primary hyperPTH - increased PTH and Ca, low P04; due to adenoma or hyperplasia
   Secondary - increased PTH, low Ca, high P04; due to renal osteodystrophy
   Tertiary - high PTH, high Ca; refractory after renal transplant

Question 17

Pheochromocytoma
5 Ps
diagnosis
treatment

Answer 17

• pheo - catecholamine producing tumor from chromaffin cells in adrenal medulla / organ of zuckerlandl (epi) or in sympathetic ganglia (norepi dominant)

5 P’s: pressure, pallor, perspiration, pain, palpitation - classic presentation is pt with newly discovered hTN and episodes of headache, flushing, palpitations

• elevated Hct, hyperglycemia
• triggers of HTN crisis - anesthesia, changes in blood flow, tumor necrosis, tyramine, surgery
• associated with MEN2A and B
• rule of 10s
• diagnose via 24 hour elevated urine (specific) and plasma-free (sensitive) metanephrines, plasma chromogranin A –> then CT A/P
• treatment - alpha blockade, beta blockade, adrenalectomy
• address pheo before other MEN2 tumors

Question 18

DDx thyroid mass

workup

Answer 18

Thyroid mass:

• thyroglossal duct cyst - elevates with swallowing, must excise
• MNG - due to childhood iodine deficiency
• benign follicular nodule
• toxic adenoma - hot nodule, hyperthyroid
• Graves
• Hashimoto
• Postpartum - painless
• Subacute - painful, transient
• Riedel - painless, firm
• Cancer - painless, cold nodules
• -> papillary - MC type; from follicular cells
• -> medullary (MEN2A,B) - of C cells (calcitonin)–> diarrhea, flushing
• -> follicular - spreads hematogenously
• -> anaplastic - lethal

workup - do TSH:

• low –> RAIU for hot nodule (RAI or excise)
• normal –> FNA

Question 19

1. sliding inguinal hernia
2. Richter hernia
3. femoral hernia

Answer 19

1. sliding inguinal hernia - type of indirect inguinal hernia where posterior wall of hernia sac is a retroperitoneal organ (bladder, colon) and is thickened; higher risk of colonic injury during repair
2. Richter hernia - only one wall of hernia protrudes into sac, prone to incarceration and strangulation but does not lead to clinical signs or radiologic evidence
   - do not manually reduce
3. Femoral hernia - in femoral canal empty space so medial to femoral nerve, artery, vein and lateral to lymphatics (NAVEL)
   - F»M, esp multigravida
   - highest risk of strangulation

post-hernia repair, could get ischemic orchitis due to damage to pampiniform plexus –> no doppler signal

Question 20

Head & Neck

1. MC site of malignant lesions of the larynx?
2. Biggest risk factor
3. MEts
4. MCC laryngitis

Answer 20

1. Glottis (squamous cell ca)
2. Tobacco use - chemicals cause inflammation –> increased cell turnover –> dysplasia
   - alcohol is not in and of itself a risk factor but is compounded
3. Mets –> MC is to the lungs
4. Laryngitis = dysphonia (hoarse voice), MCC is viral infection leading to edema of vocal cords that self-resolves within 1-2 weeks
   need ENT consult if >2 weeks

Question 21

Head & Neck

1. roles of eustachian tube
2. otitis media with effusion
3. acute otitis media
4. otomycosis

Answer 21

1. roles of eustachian tube
   - maintain gas pressure homeostasis in the ear
   - prevent infection of middle ear and reflux contents from nasopharynx
   - clear middle ear secretions
2. otitis media with effusion - kid presents with hearing problems, devlpt regression
   - MCC is acute otitis media or eustachian tube dysfunction
   - highest prevalence from ages 2-6 yo
   - risk factors - black male, smoke exposure, lower SES
   - immobile tympanic membrane with air fluid levels –> conductive hearing loss due to fluids in middle ear space
   - usually self-resolves so observe for 3 months
3. acute otitis media - otalgia (ear pain), bulging and red tympanic membrane with decreased mobility and opacification
   - <3 weeks duration
   - MCC - strep pneumo, H flu, moraxella
   - tx with abx
4. otomycosis - fullness, pruritus of ear, gray exudate and normal tympanic membrane
   - MCC - Aspergillus niger
   - risk factors - AML, DKA

Question 22

1. Acute cholecystitis
   - diagnosis
   - antibiotics
2. Cholangitis
   - causes
   - tx
3. Gallstone ileus
   - tx

Answer 22

1. Acute cholecystitis
   A. diagnose via gallbladder wall thickened > 4 mm and pericholecystic fluid
   - also look for CBD thickness (>6mm considered dilated), presence of stones
   - do chole w/in 48 hours
   B. Abx - cefoxitin (2nd gen), unasyn (amp/sulbactam)
2. Cholangitis - obstruction of CBD –> ascending infection of biliary tract
   - RUQ pain, fever, jaundice (bili >2.5)
   - + AMS, hypotension –> obstructive cholangitis
   A. Causes - gallstones MCC, strictures, parasites (ascaris, clonorchis), ERCP, stents
   B. Tx - do ERCP to decompress biliary tract, resolve sepsis, then lap chole
3. Gallstone ileus
   - remove impacted gallstone from ileocecal valve and leave gallbladder alone

Question 23

SIRS criteria

sepsis

Answer 23

SIRS 
Temperature <96.8 or >101.4
Heart rate > 90 bpm
Respiratory rate >20 or ventilated or C02 < 32
WBC <4 or >12 

sepsis - meets >2 SIRS criteria + suspected source of infection

Question 24

Pancreatitis

• diagnosis
• pathophys
• complications

Answer 24

Pancreatitis
A. diagnosis - clinical, 2/3 of the following:
- severe, persistent epigastric pain radiating to back
- findings on imaging (enlarged pancreas, sentinel loops, colon cutoff signs –> due to local ileus)
- amylase/lipase >3x ULN
*do NOT need CT scan on admission, do after 3 days if pts dont improve

B. pathophys

• gallstones impacted temporarily in CBD –> increased pressure and reflux of bile into pancreatic duct -> activation of pancreatic enzymes –> inflammation (intra, then extrapancreatic)
• vasodilation and permeability lead to fluid sequestration / leakage
• early chole for mild pancreatitis, delayed (weeks) for severe
• alcohol leads to pancreatic hypoxia and oxidative damage

c. complications
- left-sided pleural effusion (inflammation obstructs lymph drainage) –> strongly associated with severe pancreatitis
- first week is systemic (SIRS)
- w/in 3-4 weeks is local: abscess, pseudocyst (MCC death is hemorrhaging due to artery erosion)

Question 25

Pancreatitis

Ranson criteria

Answer 25

Severe - APACHE 8+, Ranson 3+, organ failure, or pancreatic complications (necrosis, abscess, pseudocyst)

Ranson 
A. Admission - GA LAW
Glucose >200
Age >55
LDH >350 
AST> 250 
WBC >16

B. After 48 hours - C. HOBBS
Calcium <8 (due to saponification)
Hct decreases 10%
O Pa02 <60
BUN increases 5
Base deficit >$
Sequestration >6L

Question 26

DDx for lower GI bleed

Answer 26

lower GI bleed: HDRAIN

Hemorrhoids
Diverticulosis
Radiation colitis
Angiodysplasia
Infections/ischemic/IBD
Neoplasm/polyps

Question 27

5 Fs of abdominal distension

Answer 27

Fat 
Fecal impaction
Fetus
Flatus (ileus or obstruction)
Fluid (ascites)

Question 28

LBO

• causes
• clinical

Answer 28

LBO
A. MCC is left-sided colon cancer (R side is IDA), then diverticulitis, then volvulus
B. Clinical - more pronounced distension, late onset vomiting, obstipation, decreased bowel sounds, feculent vomiting
- IV fluids, foley
- untwist sigmoid volvulus then sigmoidectomy if uncomplicated, go straight to resection if ischemic/perforated or a cecal volvulus (contrast enema can sometimes untwist volvulus)

Question 29

NEXUS criteria for determining who needs cervical spine xrays (AP, lateral, open mouth)

Answer 29

NSAID

Neurologic deficit
Spinal tenderness
AMS
Intoxicated
Distracting injury

Question 30

[Ortho]
Classic nerve injuries associated with fractures and what is affected: 
1. humeral head 
2. midshaft humerus
3. supracondylar
4. distal radius
5. hip fracture
6. fibular head

Answer 30

1. humeral head - axillary –> arm abduction
2. midshaft humerus - radial –> elbow, wrist extension
3. supracondylar - anterior interosseus (median) –> handgrip (no sensory problems)
4. distal radius - median –> thumb opposition
5. hip fracture - sciatic (peroneal) –> knee flexion
6. fibular head - fibular / peroneal –> foot drop, dorsiflexion, eversion

Question 31

[Ortho]

1. most important determinant of severity for open fracture
2. abx coverage
3. greatest risk hemorrhagic shock
4. what to worry about crush injuries

Answer 31

1. energy imparted to the wound
2. abx coverage -
   Grade I and II - Gram + –> 1st gen cephalosporin
   Grade III - ceph + aminoglycoside
   continue for 24 hours after wound closure
   if wound has dirt/soil - Clostridium –> PCN, Tetanus immunoglobulin (for dirty wounds, if <3 vaccine doses; don’t give for clean wounds), tetanus toxoid vaccine (if last dose was >5 years ago for dirty or >10 for clean)
3. greatest risk hemorrhagic shock - pelvic fracture
4. crush injuries –> compartment syndrome, rhabdo, AKI

Question 32

[Ortho]

1. Froment sign
2. treatment of carpal tunnel
3. what is CTS associated with
4. distinguishing prox from distal median nerve injury

Answer 32

1. Froment sign - test of ulnar nerve, thumb adductor in which examiner can pull the paper from pt’s hand
   - low ulnar lesion has severe ulnar claw
2. CTS - splinting wrist, injection of corticosteroids, then surgical (cutting of transverse carpal ligament)
   - unless there is thenar atrophy - indication for surgery
3. carpal tunnel - hypothyroidism
4. distinguishing prox from distal median nerve injury - palmar cutaneous branch of median nerve, runs above carpal tunnel –> spared in distal injury

Question 33

[Peds]

1. Congenital diaphragmatic hernia - how it leads to NRDS
2. mgmt of NRDS
3. what is duodenal atresia associated with

Answer 33

1. CDH –> pulmonary hypoplasia –> high resistance in pulmonary arterial bed (pulmonary hypertension), does not reverse as it should when infant takes its first breath –> hypoxemia, acidosis, hypotension –> pulmonary vasoconstriction *directly correlated with survival
   - most commonly on left, posterolateral
2. Mgmt - intubate ASAP
   - place orogastric tube, take CXR –> tracheoesophageal fistula, CDH, choanal atresia
3. duodenal atresia - (double bubble sign on Xray) - down syndrome, cardiac defects, annular pancreas

Question 34

[Peds]

Mgmt of bilious vomiting in babies

Answer 34

Bilious vomiting - green or yellow, obstruction after ampulla of vater

IVF, NGT
A. stable –> Xray –>
prox obstruction (min bowel gas) –> UGI contrast study to look for malrotation, if negative consider hernia, adhesions, Hirschsprung
distal obstruction (lots of bowel loops) –> abdominal US to look for intussusception
B. unstable –> Abx and OR for ex lap, suspect malrotation with midgut volvulus (failure of normal 270 rotation around SMA –> closed loop obstruction)
*midgut volvulus most commonly has normal Xray findings

Question 35

[Skin]

1. implication of culturing Clostridium septicum from wound?
2. hard signs of NSTI

Answer 35

1. Clostridium septicum - associated with occult malignancies esp colon cancer
2. NSTI hard signs - hemodynamic instability, crepitus, bullae, skin necrosis
   - acute onset pain, swelling, erythema
   - clinical diagnosis –> needs surgical debridement and second look surgery

Question 36

DDx for postop bleeding

TRALI vs ARDS

transfusion rxns 
A. febrile nonhemolytic
B. acute hemolytic
C. allergic
D. anaphylactic

Answer 36

• surgical (artery/vein)
• medications (anticoags)
• inherited eg vW, hemophilia
• liver failure (Reduced clotting factors) –> FFP
• renal failure (uremia impairs platelet function) –> desmopressin and dialysis
• DIC

TRALI - blood transfusion related acute lung injury

• leading cause of fatalities, non-cardiogenic pulm edema
• donor Ab attack recipient WBCs –> complex aggregates in lung vasculature –> inflammation –> pulmonary edema
• requires fluid resuscitation, pressors

ARDS:

• b/l fluffy white infiltrates on CXR
• normal PCWP < 18 (means its not cardiac)
• Pa02 / Fi02 < 200

transfusion rxns
A. febrile nonhemolytic - min to hours, due to cytokines, give tylenol
B. acute hemolytic - within 24 hrs, due to ABO mismatch –> fever, low BP, flank pain, hemoglobinuria, jaundice
C. allergic - due to plasma in donor blood, give antihistamine (diphenhydramine)
D. anaphylactic - IgA deficiency, give epi

Question 37

normal urine output and assessing volume status

Answer 37

normal urine output = 50-100 mL / hour

oliguria = <0.5-1 ml/kg/hour OR <400-500 mL in 24 hours

first make sure foley is not clogged, flush it
then review all meds and dose adjust renally excreted drugs, then fluid challenge (500 mL bolus NS in 30 min) –> urine output will increase if oliguria is due to hypovolemia
if not:
- put in central line –> CVP (nl 8-12) will help assess volume status
- if oliguric after normal CVP is reached –> consider postrenal and and intrinsic renal etiologies

oliguria normal in the first 24 hours postop due to increased aldosterone and ADH

Question 38

1. difference non-cardiogenic and cardiogenic pulmonary edema
2. PE lab values

Answer 38

1A. Cardiogenic - acute cardiac event eg MI, LVF, arrhythmia
S3 gallop, JVD, crackles + cool extremities
elevated PCWP >18
tx - reduce preload and afterload, pressors
on POD3 can be due to third spacing, IVF goes back to vasculature and overwhelms the heart

B. Non-cardiogenic - PNA, ARDS, pulm contusion, fat emboli
due to increased permeability 2/2 cytokine signaling / inflammation; wide A-a gradient
tx - ventilatory support

2. PE – start heparin, do CTa, b/l leg doppler + V/Q scan
   respiratory alkalosis, hypoxemia, and increased A-a gradient
   EKG - sinus tach, S1Q3T(inverted)3 - due to RV strain
   normal CXR usually
   can be low-risk, submassive (RV strain), massive (hypotension)

Question 39

[Trauma]
1. Describe types of shock and effects on PWCP (preload), CO, SVR (Afterload)

2. Neurogenic vs spinal shock

Answer 39

1. Shock - PCWP ~ LAP

A. Hypovolemic (trauma, burn) - low PCWP, low CO, high SVR

B. Cardiogenic (MI, HF, arrhythmia) - high PCWP, low CO, high SVR

C. Obstructive (tamponade, tension pneumo, PE) - decreased preload

D. Distributive - low PCWP, low SVR

i. neurogenic - dry skin, low CO
ii. sepsis, anaphylaxis - warm skin, high CO

2A. Neurogenic shock - SNS outflow through spinal cord disrupted –> vasodilation, bradycardia, hypotension

B. Spinal shock - temporary syndrome with flaccid paralysis below level of injury with loss of all reflexes, urinary and rectal tone

Question 40

[Trauma]

1. 5 major sources of blood loss in trauma
2. how much blood loss to be tachycardic? hypotensive?
3. DDx for pulsating mass
4. DDx narrowed pulse pressure?

Answer 40

1. chest, abdomen, pelvis, long bones, external
2. Tachycardic (100+) - 750-1.5L blood loss
   Hypotensive (SBP < 90) - 1.5-2L blood loss
3. Pulsating mass - AV fistula, aneurysm, pseudo-aneurysm (full thickness injury that is temporarily tamponaded by surrounding soft tissue, pulsating is due to blood being pumped into cavity)
4. narrow PP = <30 mmHg –> compromised stroke volume *worry when diastolic p starts rising
   DDx - pericardial tamponade, hypovolemic shock, cardiogenic shock

Question 41

[Trauma]
Neck injury –
A & B. Hard vs soft signs
C. Mgmt of penetrating, stab, blunt trauma based on zones

Answer 41

Neck injury
A. Hard signs –> expanding hematoma, shock, hematemesis, neuro deficit, airway compromise –> OR stat
B. soft signs –> subQ air, dysphagia, chest tube air leak

C. Mgmt

Zone 3 (above mandible)
penetrating - aortagram, triple endoscopy 
stab - observe

Zone 2 (mandible to cricoid)
penetrating - doppler maybe surgery
stab - observe 

Zone 3 (below cricoid) 
penetrating eg GSW - aortogram, esophogram, bronchoscopy 

blunt –> do lateral or CT cervical spine

Question 42

[Trauma]
Lethal 6 injuries of thoracic trauma

Hidden 6 injuries

Answer 42

Lethal:

1. airway obstruction - stridor, gurgling, hematoma
2. tension pneumo - tracheal shift away, unilateral absent breath sounds + JVD + hypotension + dyspnea + tachypnea
3. open pneumo - open injury
4. massive hemothorax - total whiteout of lung field
5. flail chest - 2+ fracture sites in 2+ consecutive ribs
6. cardiac tamponade - beck’s triad (JVD, hypotension, muffled heart sounds)

Hidden:

1. Blunt aortic injury - deceleration injury, trachea deviates right
2. esophageal injury - penetrating injury, subQ air
3. tracheobronchial injury
4. diaphragmatic rupture - on L side, see bowel in chest
5. blunt cardiac injury
6. pulmonary contusion (lungs white out on CXR)

Question 43

[Trauma]
1. levels of burn injuries + how to determine severity
2. alkali vs acidic vs electrical
3. fluid use
Parkland formula for fluid resuscitation in burn victims
4. Topical abx

Answer 43

1. Burns
   First degree - superficial (epidermis) - dry, red painful
   Second degree - partial thickness - warm, blistered
   superficial = painful while deep = painless
   Third degree - full thickness (epidermis + dermis) - painless, leathery, do not blanch
   severity = total body surface area of 2nd or 3rd degree burns
2. alkali worse than acidic bc they penetrate tissues deeper
   acidic –> coagulation necrosis
   alkali –> liquefactive necrosis
   electrical –> do EKG, monitor
   *if pt has myglobinuria - check K+ due to rhabdo
3. use LR bc use of NS will lead to hyperchloremic metabolic acidosis
   watch for hyponatremia, hyperkalemia
   Parkland =4 * weight in kg * TBSA
4. Topical abx
   - silver sulfadiazeine - standard, causes leukopenia
   - silver nitrate - causes hypoK and hypo Na
   - mafenide - for deep burns bc penetrates eschar, hurts like hell
   - triple abx - for eyes

Question 44

[GI]

1. DIfference acute vs chronic gastritis
2. Mgmt of variceal UGIB
3. intestinal vs diffuse gastric cancer

Answer 44

1A. Acute gastritis - erosive, superficial inflammation of lining of stomach due to NSAIDs, alcohol, steroids, uremia

B. Chronic gastritis - non-erosive inflmmation of mucosa

• fundus dominant - pernicious anemia
• antral dominant (most common) - H pylori

2. Variceal bleed - abx ppx, somatostatin (octreotide)
   endoscopic band ligation
   propanolol to prevent future GI bleeds

3A. intestinal - well-differentiated, decreasing incidence as H pylori decreases, due to environmental factors
B. diffuse - infiltrative, generalized hypertrophy and leads to linitis plastica

Question 45

Fluids

1. NS vs LR
2. maintenance fluids + rate
3. Correcting hypernatremia vs hyponatremia
4. Correcting hypokalemia and metabolic alkalosis

Answer 45

1. LR - hypotonic to plasma (Na = 130), physiologic K and Cl; can lead to metabolic alkalosis
   NS - hypertonic to plasma (Na = 154), low pH and high Cl load can cause metabolic acidosis
2. maintenance = 1/2NS + 20KCl (if peeing)
   rate per day = 1500 mL + [(kg - 20kg) x 20 ml/kg/day]
   e.g. for 60 kg –> 1500+ (40x20) = 2300 ml/day

3A. Hypernatremia - every 3 meq/L above 140 –> 1 L water lost

• replete with D5 1/2NS
• if acute –> use more diluted fluid eg D5 or D51/3NS

B. Hyponatremia -

• increased volume (CHF, nephrotic cirrhosis) - fluid restrict, diuretics, hypertonic saline IF <110 or sympomatic
• nl volume e.g. SIADH –> fluid restriction
• decreased volume e.g. pt losing GI fluids and forced to retain water –> isotonic fluids

4A. Hypokalemia - IV K at 10 meq/hr, monitor renal fx
B. Alkalosis - KCl bw 5-10 mEq/hr

Question 46

1. Contraindications to surgery
2. Most important predictors of perioperative mortality (Goldman’s index) and what you should check preop
3. meds to stop prep

Answer 46

1. Contraindications to surgery
   - absolute - DKA
   - poor nutrition - albumin < 3, transferrin < 200, weight loss < 20%; do enteral feedings
   - liver - PT > 16, ammonia >15, bili > 2
   - smoker - stop 8 weeks before surgery
2. predictors of periop mortality
   - CHF –> check EF if <35% –> no surgery
   - MI (in last 6 mos) surrogate for cardiovascular status –> do EKG –> stress test –> Cath lab for reperfusion (stent, CABG)
   - arrhythmia
   - age > 70
   - aortic stenosis
   - CKD - worry if BUN > 100 bc of uremic platelet dysfunction –> normal platelets but risk of bleeding
3. Meds to stop
   - aspirin, NSAIDs, Vit E (2 weeks preop)
   - warfarin (5 days) - INR <1.5
   - metformin - risk of lactic acidosis

Question 47

Ventilator settings

1. Assist control
2. Pressure support
3. CPAP
4. PEEP

What to do if:

1. Pa02 too low
2. PaC02 too low (pH high)

Answer 47

1. Assist control - Set tidal volume and respiratory rate but if patient takes breath, vent gives volume
2. Pressure support - patient controls rate but vent gives some tidal volume; important for weaning
3. CPAP - patient has sufficient respiratory drive but continuous positive pressure so alveoli stay open
4. PEEP - used in ARDS or CHF, positive pressure at end of exhalation

If…

1. Pa02 too low –> increase Fi02
2. PaC02 too low (pH high) –> decreased RR or TV (TV is better bc you’re not dead space ventilating as with RR)

Question 48

Chest trauma tx

1. Pneumothorax - tension, open
2. Hemothorax
3. Flail chest

Answer 48

1. Pneumothorax
   - tension - absent breath sounds, tracheal deviation away, JVD (think tension or tamponade), subQ emphysema; one-way valve due to lung injury –> needle in midclavicular 2nd intercostal space, then chest tube
   - open - sucking chest wound –> leads to tension
   - small spontaneous - 100% 02, avoid PEEP
2. Hemothorax - absent breath sounds, dullness to percussion
   - chest tube –> if >1.5L immediately or >600 mL in 6 hours –> go to OR for VATS
3. Flail chest - 2+ fractures in 2+ consecutive ribs
   - give 02 and nerve block for pain control *NOT opiates (decrease RR)
   - underlying pulm contusion (whiteout on CXR) –> give diuretics bc sensitive to fluid overload

Question 49

1. Which types of abscesses do you NOT drain as first line tx?

Answer 49

Normally I&D abscesses

1. do NOT do that for lung abscesses - tx with abx, IV clinda or PCN
   - surgery if abscess > 6 cm, abx fail, or empyema
2. Liver abscesses caused by Entamoeba histolyica
   - give metronidazole
   * bacterial liver abscesses (ecoli, bacteroides, enterococcus) – drain and IV abx