Surgery Flashcards
What agent is given to patients with extreme hypotension (low BP) during heart surgery that eventually requires bypass?
Methylene Blue
MOA: inhibits guanylate cyclase and production of cGMP –> reduced responsiveness of vasodilators (nitric oxide)
Internal vs External Carotid resistance via Doppler?
*External: when not using somatic (muscles) parts of body, the blood vessels are vasoconstricted to restrict blood flow when it’s not needed there. This is why high initial pressure on doppler followed by sharp drop-off. (picked up on doppler)
Supplies face muscles (somatic areas)
*Internal: blood flow to visceral organs needs to be high at all times. This is why there is high (loud) diastolic phase during doppler b/c blood flow is still high (picked up on doppler)
These vessels feed important organs (brain, kidney) and will have high flow
During carotid endarterectomy, where do you clamp vessels?
When closing up, what order do you release the vessels to assess for bleeding?
Clamp proximal and distal to place of operating (common carotid and both internal & external carotids)
1) Open distal artery first (common carotid portion furthest from head) to assess for any bleeding from suture site
2) Then release the external carotid artery –> if there is any residual gunk/plaque, you don’t want it going to the brain and stroking the patient. Going down the external carotid to face is less damaging.
3) Release internal carotid artery last!!
What can be given to prevent contrast-induced nephropathy in people w/ renal insufficiency?
What 2 things should be avoided?
Aceytlcysteine w/ plenty of IV fluids
Avoid volume depletion and NSAIDs
How many days before surgery do you need to d/c Warfarin?
3-4 days pre-op
*Switch from warfarin to either heparin/LMWH until surgery than start either again 12 hrs post-op and maintained until INR >2
How long before a surgery should you stop smoking?
at least 4 weeks pre-op (6-8 weeks)
Cause of fever immediately after initiation of anesthesia?
Malignant hyperthermia
Tx: Dantrolene, 100% O2, cooling blankets
Common cause of fever post-op day 0-1?
Atelectasis or pneumonia
Patient post-op develops a fever on post-op day #1 and it persists for 2-3 days?
Pneumonia
Fever presenting post-op day 3-5?
Post-op UTI
UTI: 3 letters - 3rd days after see fever
DVT: V is roman numeral for 5 - 5 days after see fever
Wound: W for week (1)
Deep Abscess: 4 letters + 9 letters = 13 (9-13 days)
How many days after operation do you see fever from wound infection?
5-8 days
Maintenance fluid calculation?
4-2-1 rule
or
wt (kg) + 40 = mL/hr
Adequate urine output?
0.5 mL/kg/hr (30mL/hr)
Maintenance IV fluid of choice for adults? children?
Adults: D5 1/2 NS + 20 mEq KCl/L
Children: D5 1/4 NS + 20 mEq KCl/L
Composition of 0.9 NS?
Na: 154 K: 0 Osm: 308 pH: 6.0 Cl: 154
Composition of extracellular fluid?
Osm: 290 Na: 140 K: 4.5 Cl: 108 pH: 7.4 Lactate: 5
Composition of LR?
Osm: 273 Na: 130 K: 4 Cl: 110 HCO3: 27 Ca: 3 pH: 6.5 Lactate: 28
Composition of D5W?
Osm: 252 Na: 0 K: 0 Glucose: 50g/L pH: 4.5
Composition of D5 1/2 NS?
Osm: 450 Na: 77 K: 0 Cl: 77 Glu: 50
Composition of PlasmaLyte?
Osm: 294 Na: 140 K: 5 Cl: 98 pH: 7.4
Name for chronic leg discoloration from chronic venous insufficiency?
Lipodermatosclerosis or venous stasis dermatitis
What are better for moisture retention and delivery of medications - creams or ointments?
Ointments
What is Leriche syndrome?
Aortoiliac occlusive disease –> form of peripheral artery disease involving bifurcation of abdominal aorta
Triad:
1) B/L hip/buttock/thigh claudication (worse w/ walking)
2) Decreased/absent femoral pulses
3) **Impotence –> if not present, not Leriche!
What is Leriche syndrome?
Aortoiliac occlusive disease –> form of peripheral artery disease involving bifurcation of abdominal aorta
Triad:
1) Buttock/thigh claudication
2) Decreased/absent femoral pulses
3) Impotence
6 P’s of Compartment Syndrome?
Pain, Pallor, Paresthesia, Paralysis, Poiklothermia, Pulseless
Daily protein needs for TPN?
25 kcal/kg/day or 1-1.5 g/kg/day
3 common causes of appendicitis?
Bowel fecalith
Lymphoid hyperplasia (viral infection) - children
Tumor
Testing modality for children w/ suspected appendicitis? Women? Men?
Children and women –> Ultrasound
Most adults over 50 –> CT scan
2 pre-op treatments for appendicitis?
Crystalloid fluid
Abx: cefazolin + metronidazole
First step in appendectomy?
Ligate appendicular artery (branch off of ileocecal from SMA)
Borders of inguinal canal?
Roof: fibers of internal oblique & transversus abdominus
Floor: inguinal ligament
Anterior: external oblique aponeurosis
Posterior: transversalis fascia
Borders of Hasselbach’s triangle?
Lateral border of rectus abdominus
Inferior epigastric artery
Inguinal ligament
What congenital defects allows indirect inguinal hernias to occur?
Patent processus vaginalis
Borders of femoral canal?
Anterior: inguinal ligament
Posterior: Cooper’s ligament (periosteum of superior pubic ramus)
Medial: lacunar ligament
Lateral: femoral vein
3 stages of hernia progression?
Reducible
Incarcerated (non-reducible –> leads to lymphatic and venous obstruction in the loop of bowel –> overtime leads to compression and obstruction of arterial flow to loop of bowel)
Strangulated (ischemic/necrotic bowel from lack of blood supply)
Drug commonly avoided due to Sphincter of Oddi spasm?
Morphine (tested but not practiced)
Term for air located in the gallbladder?
Emphysematous Cholecystitis
Charcot’s triad?
Reynold’s pentad?
1) Fever & chills
2) RUQ pain
3) Jaundice
* Also see increased ALP
* *Seen in acute ascending cholangitis**
Charcot triad + hypotension & mental status changes
What is triangle of Calot?
Area where ligation of cystic artery and duct occur for gallbladder removal
“3 C’s”
1) Cystic duct
2) Common hepatic duct (BEFORE cystic duct joins)
3) Cystic artery
Common feature of R-sided colon cancer?
Fe-def anemia
*Microcytic anemia in older adult (>50) = colorectal cancer until proven otherwise (also think GI bleed)
Common feature of L-sided colon cancer?
Bowel changes
Pencil-thin stools, constipation, diarrhea
Best initial test for colorectal cancer?
DRE –> if (+) then to colonoscopy
In adults, 3 most common causes for small bowel obstruction?
Adhesions (prior abdominal surgery)
Hernias
Tumors (suspect w/ no prior abd surgeries or hernias)
How do gallstones get into the small bowel and cause obstruction?
Cholecystoenteric FISTULA forms (b/w gallbladder and small bowel) and allows passage of large gallstones into bowel –> obstruct the ileocecal valve
X-ray findings for gallbladder fistula?
Air in biliary tree
Possible radio-opaque mass in RLQ
2 common causes for large bowel obstruction?
Tumors
Volvulus
Bilious vomiting in newborn?
Malrotation of midgut volvulus until proven otherwise!
Causes for bowel obstruction in children?
Volvulus, intussusception, hernias
If they don’t pass meconium:
At all = CF
During initial 24 hrs = Hirschsprung’s disease
Common complication of bowel obstruction?
Vomiting –> hypokalemic, hypochloremic metabolic alkalosis
Hypokalemic b/c the alkalosis causes H+ to efflux from cells for buffer –> K+ moves into cells as H+ moves out –> drop in K+ level
X-ray findings for small bowel obstruction?
Dilated loops of small bowel
“Step-ladder” appearance –> air-fluid levels
Treatment for SBO?
“Suck & Drip”
1) NPO
2) NG tube to suck out all gas in GI tract
3) Aggressive IV hydration w/ IV crystalloid
4) Foley placed to monitor urine output for hydration status
5) Correct electrolyte imbalances
*Surgery is only needed w/ complete obstruction or clinical/radiographic signs of ischemia, necrosis, or perforation
Most common area for AAA?
Best method of testing?
Below renal artery bifurcation (no vasa vasorum causes weakening in arterial wall)
CT scan
What size do AAA become surgical candidates?
> 5.5cm diameter
Femoral triangle?
Lateral border: sartorius muscle
Medial border: adductor longus muscle
Superior border: inguinal ligament
Treatment for large bowel obstruction?
Enema, decompression w/ rectal tube, colonoscopy
Name for acute colonic pseudo-obstruction causing dilation of colon without any actual mechanical obstruction?
Once this is diagnosed, what is treatment?
Ogilvie syndrome (often in elderly w/ extra-abdominal surgery)
Tx: Neostigmine (potent cholinesterase (-) & parasympathetic agonist that stimulates colonic contraction and subsequent decompression of the bowel)
What is blood supply of internal & external hemorrhoids and which are painful?
Internal: dilated superior rectal plexus located ABOVE dentate line and NOT painful
External: dilated inferior rectal plexus loctated BELOW dentate line and YES are painful
Management of hemorrhoids?
Conservative (sitz baths, stool softeners, high fiber diet)
Surgical management:
Internal: rubber band ligation
External: hemorrhoidectomy
What condition should you suspect w/ an anal fissure, perianal abscess, or anorectal fistula fail to heal?
Crohn’s disease
What is Goodsall’s rule of anorectal fistulas?
Anterior fistulas connect w/ rectum in a straight line
Posterior fistulas go towards a midline internal opening in the rectum
During organ transplantation, in what organ are antigenic reactions (acute, hyper acute, delayed) not very common?
What is most common complication?
Liver
*Most common cause of early functional deterioration is technical problems w/ biliary & vascular anastomoses –> if they appear normal, then do liver biopsies to confirm organ rejection
Risk factors for squamous cell carcinoma of the mouth? Common precursor lesions?
Smoking & alcohol
Erythroplakia & leukoplakia
Firm, non-tender mass in front of L ear present for 4 months w/ limited mobility and not fixed to deep tissues or to overlying skin. FNA is done, but indeterminate. What do you suspect? Next best step?
Parotid tumor (pleomorphic adenoma or adenoid cystic tumor)
Next step: superficial parotidectomy w/ sparing of facial nerve
*Repeat biopsies are NOT advised b/c of potential damage to facial nerve from scar tissue formation
Fever, perineal pain, irritative urinary symptoms, very tender prostate on exam? Tx?
Acute Prostatitis
Tx: Fluoroquinolones 4-6 weeks (broad G(-) & (+) coverage)
R hip pain radiating down femur to the knee. Hx Crohn’s w/ recent flair controlled w/ prednisone for 2 weeks. Pain worse on exertion & relieved w/ NSAIDs. Limited ROM w/ R hip, especially w/ external rotation. X-ray shows dulling of femoral head only. What is next step in diagnosis?
Avascular necrosis of femoral head secondary to exogenous steroid use!
*Femoral head especially at risk due to poor blood supply (medial fem circumflex via profunda femoris)
What is a Pringle maneuver?
Hemostats used to clamp the Portal Triad in hepatoduodenal ligament to control possible liver bleeding.
If done and bleeding still persists in RUQ –> think hepatic vein or IVC behind the liver
In someone with epidural hematoma that suddenly becomes unresponsive, what is the definitive management?
Surgical evacuation of the hematoma
Elderly at risk for what types of fractures? Why? Best initial test?
Femoral fractures (hip fracture due to FALLS! - underlying cormorbidities also)
Diag test –> X-ray of hip/femur
What is an absolute indication for CT scan to the head?
Loss of consciousness secondary to head trauma
WITHOUT contrast - contrast reserved for mass lesions in the brain
When is contrast used for head CT’s?
Suspecting mass lesions in head
Method for eliminating pyogenic liver abscess?
Amebic liver abscess?
Pyogenic abscess –> percutaneous drainage (Abx won’t touch it!)
Amebic abscess –> metronidazole (E. histolytica) & then percutaneous drainage if no resolution w/ Abx
Pt w/ recent pituitary surgery for prolactinoma develops lethargy, confusion, and becomes comatose. Her urine output is elevated and is receiving modest IV fluids. What is the cause? Treatment?
Central diabetes insipidus –> damage to other parts of anterior/posterior pituitary & their hormones
- Lack of ADH = massive/rapid water loss via kidneys causes hypernatremia (causes CNS symptoms) - Tx: IV fluids and desmopressin (ADH-analouge)
Patient is actively bleeding per rectum. A NG tube is placed & aspiration reveals clear, green fluid w/o blood. How does this help you identify location of GI bleed?
If aspirate is clear = bleed is DISTAL to Ligament of Trietz (where duodenum becomes jejunum)
X-ray findings of SBO + air in biliary tree (pneumobilia) is indicative of what?
Gallstone ileus in ileocecal valve from gallbladder-small bowel fistula
Common sequela after acute cholecystitis
2 complications of femoral fractures. What signs do you see with each?
Fat emboli –> usually several days after fracture and see respiratory failure
Hypovolemic shock –> massive blood loss into thigh cavities
Common complication after acute pancreatitis seen w/ high fevers and leukocytosis?
Pancreatic abscess
CT scan of abdomen to locate abscess for drainage
What is cause for pneumaturia (peeing bubbles) and fecaluria?
What test would confirm?
What are 3 most common causes?
Colovesical fistula (colon & bladder)
CT scan to confirm
1) Diverticulitis 2) Sigmoid cancer 3) Bladder cancer
Someone vomiting bright red blood. What is first step in management? Second? Third?
1) Examine mouth & nose –> r/o epistaxis!!!
2) Lavage gastric contents via NG tube
3) Upper Endoscopy
Best treatment for acute ascending cholangitis?
1st: supportive care + broad-spectrum Abx
2nd: ERCP
Evaluates biliary obstruction & is both diagnostic & therapeutic (decompression of dilated common bile ducts)
Best treatment for acute ascending cholangitis?
ERCP –> evaluates biliary obstruction & is both diagnostic & therapeutic (decompression of dilated common bile ducts)
What nerves are at risk for damage in inguinal hernia repairs?
Iliohypogastric, ILIOINGUINAL, genitofemoral (genital branch), lateral femoral cutaneous
5 indications for surgery on GI tract?
1) Bleeding
2) Perforation
3) Obstruction
4) Retractable symptoms
5) Neoplasm
Triad of lab findings indicating the need for a Damage Control Situation (stopping operation to stabilize patient for several hrs before returning to surgery)?
1) Hypothermia (5mmol)
2) Coagulopathy (increased PT/INR & PTT)
3) Acidosis (low pH & lactate >5mmol)
Most common malignant tumor in appendix?
Carcinoid tumor
Purpose of the large colon?
Water absorption
Aside from niacin deficiency, what condition causes diarrhea, dermatitis, dementia?
Carcinoid syndrome (from decreased niacin production)
What are the signs of carcinoid syndrome?
“Be FDR”
Bronchospasm
*Flushing (skin - early & frequent)
Diarrhea
R-sided heart failure (valve failure - tricuspid)
What lab test is used for carcinoid tumors?
Treatment for carcinoid?
5-hydroxyindolacetic acid (HIAA)
Tx: octreotide (somatostatin analogue)
2 most common causes for fistula formation?
Diverticulosis & cancer
Newly-developed Fe-deficiency anemia in postmenopausal woman or older man?
Colorectal cancer
Triad often seen w/ diverticulitis?
Fever
LLQ pain/diffuse abd pain
Leukocytosis
What tests are contraindicated in suspected diverticulitis?
Barium enema, colonoscopy –> risk of perforation
Consider this diagnosis in patient w/ atypical chest pain (normal cardiac exam) and symptoms of GERD?
Hiatal hernia
What unique structure is found in males inguinal canal? females inguinal canal?
Males: spermatic cord w/ vas deferens
Females: round ligament of uterus
Why is shoulder pain a common complaint post-laparoscopy?
CO2 used for insufflation can irritate the diaphragm (direct pressure or cell death from temp changes) –> referred pain via phrenic nerve
What abdominal test/procedure is strictly therapeutic?
ERCP
24 yo woman who recently gave birth presents w/ extreme rectal pain when defecating and bright red blood on toilet paper. She feels pain when coughing and it’s relieved when standing. Where is most common location of this lesion?
Anal fissure –> Posterior midline BELOW dentate line
In a person w/ claudication, what disease process are thinking and what is next best test? What limit denotes disease?
Peripheral vascular disease (arterial occlusive disease)
*Ankle-brachial index (ABI) –> measures systolic BP in ankle divided by brachial artery via Doppler
ABI
In a person w/ claudication, what disease process are thinking and what is next best test?
Peripheral vascular disease (arterial occlusive disease)
*Ankle-brachial index (ABI) –> measures systolic BP in ankle divided by brachial artery via Doppler
Allogenic bone marrow graft to someone results in fever, diarrhea, generalized rash, cough, jaundice, and intestinal bleeding. What is the cause and complication of the marrow transplant?
Graft-vs-host disease (GVHD)
T lymphocytes (cytotoxic T cells & NK cells) of the donor tissue attacks the immunocompromised host! Symptoms in stem are classic
CT scan shows small bowel thickening w/ air in the bowel wall (pneumatosis intestinalis/coli) w/ hx of CHF, CAD. What is it?
Non-occlusive mesenteric ischemia (NOMI) –> vasoconstriction of mesenteric vessels OR hypoperfusion (shock) in stenosed vessels
What 2 broad categories must you consider w/ CT scan of small bowel inflammation w/ air in abdominal wall?
Mesenteric ischemia & infection (gas-producing organism)
What trauma situation warrants an exploratory laparotomy?
Gunshot wound to abdomen
3 complications of AAA repair?
1) Renal failure (atherosclerotic emboli of renal arteries, contrast-induced nephropathy, occlusion of renal arteries w/ graft)
2) Ischemic bowel (occlusion of IMA by graft-stent)
3) Spinal cord ischemia (disruption of artery of Adamkiewicz @ T12 –> causes anterior cord syndrome or paralysis of legs)
2 days post-op AAA repair, man develops abdominal pain w/ bloody diarrhea w/ falling Hgb & rising WBC count. Next best step? What is it?
Next step: urgent colonoscopy (gold standard to visualize cyanotic or shedding mucosa)
Ischemic colitis: complication of AAA repair b/c origin of IMA is covered by aortic graft. Don’t have adequate collateral circulation via Marginal artery of Drummond from SMA
- Ischemia of descending and sigmoid colon (rectum spared b/c of different arterial supply than IMA) * *Blood diarrhea w/ leukocytosis in this setting = mesenteric ischemia
Next step in management for a person who sustains a closed fracture w/ weakened but present pulses?
CT angiogram –> have to assess possibility for VASCULAR injury
“Hard” signs indicating vascular injury and warranting immediate surgical exploration?
Active hemorrhage Expanding hematoma Pulse absence Bruit or thrill Distal ischemia (arteiral insufficiency --> pain, pallor, poikilothermia, paresthesias, paralysis, pulseless)
1 week hx of mass in scrotum that is painless, smooth, nonindurated and located above the testicle. Ultrasound reveals a cystic lesion w/o internal echoes in R epididymus. What is next best step?
No further management needed –> if asymptomatic, nothing else needed
Either spermatocele or epididymal cyst
Man feels a new budge in his groin that is causing him pain. He has a fever (100.4) and has mild R-sided erythema. A tender mass is felt at internal inguinal ring that is unaffected by cough or strain. What is next appropriate step?
Emergent surgical repair –> need to save the bowel or debride necrotic tissue
Hernia’s are rarely painful
Painful, red, fever = incarcerated hernia
Most common cause of post-op decreasing urine output? What test helps confirm?
Hypovolemia (procedure w/ large blood loss) –> immediately after surgery the patient will “3rd space” the fluids given to them –> need about 3x as much fluid to maintain BP and urine output
Fluid challenge –> if hypovolemic, will have increased BP and urine output; if not, renal failure it is
A solitary thyroid nodule (2cm) w/ normal TSH levels is found. What is the next best step?
Fine needle aspiration (FNA) –> most thyroid nodules are BENIGN, but need to r/o cancer anyway
“Rule of 9’s” for adult burn patients?
Estimated percentage of body surface area affected by the burn: Anterior trunk: 18% Posterior trunk: 18% L leg (entire): 18% R leg (entire): 18% L arm (entire): 9% R arm (entire): 9% Head (entire): 9%
What is common cause of death in burn patients?
CO poisoning from inhaled smoke
*If unexpected neurologic symptoms occur –> get arterial carboxyhemoglobin level b/c pulse oximetry can be falsely elevated.
Pain on radial side of wrist & first dorsal compartment. Pain is reproduced by having patient hold their thumb inside their closed fist and forcing wrist into ulnar deviation. What is most likely diagnosis?
de Quervain’s tenosynovitis –> tenosynovitis of extensor pollicus braves and abductor pollicus longus
- Pain on radial side of wrist & first dorsal compartment
- Pain reproduced by Finkelstein test (hold thumb inside closed fist and ulnar deviate hand)
Dysphagia starting w/ meat –> then other solids –> then soft foods –> liquids –> saliva. Smoking and drinking are risk factors?
Squamous cell carcinoma of esophagus
Smoking & drinking = squamous
72 yo woman w/ femoral neck fracture & affected leg appearing shorter and externally rotated. What is next best step in mgmt?
Replace femoral head w/ metal prosthesis
*The femoral head is tenuous & can easily develop avascular necrosis of femoral head
What is Nissen fundoplication and indications for performing this surgery?
Laparoscopic procedure that wraps the fundus of the stomach 360 degrees around the GE junction to “replace” or strengthen the lower esophageal sphincter.
Indications:
- GE reflux causing damage to lower esophagus (esophagitis) - Refractory symptoms despite medical therapy - Long term medical therapy is undesirable to younger patients
*Treatment of choice for pts w/ normal length and motility of esophagus
Complication of Billroth II procedure w/ severe diarrhea, wt loss, and severe halitosis?
What other gastric compliant usually associated w/ this?
Gastrojejunocolic fistula –> fecal contamination of gastric contents (halitosis!)
*Fistula develops from an UNTREATED marginal ULCER that develops in the antecolic anastomosis –> if left untreated, will eventually erode into jejunum allowing feces to pass back into stomach (halitosis & diarrhea)
Complication of Billroth II procedure w/ severe diarrhea, wt loss, and severe halitosis?
What other gastric compliant usually associated w/ this?
Gastrojejunocolic fistula –> fecal contamination of gastric contents (halitosis!)
*Fistula develops from an UNTREATED marginal ULCER that develops in the antecolic anastomosis –> if left untreated, will eventually erode into jejunum allowing feces to pass back into stomach (halitosis & diarrhea)
Posterior duodenal ulcers can cause massive bleeding from what vessel?
Gastroduodenal artery (lies posterior to duodenum)
What is Billroth II procedure?
What are the indications?
Greater curvature of stomach is connected to first part of jejunum in side-to-side manner. Often involves resection of antrum of stomach.
Indications:
1) Refractory peptic ulcer disease 2) Gastric adenocarcinoma