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402
P. Thosani
– Arteriography (use brachial puncture if femo-
ral pulses absent)
– 2-D echocardiogram (should not delay treat-
ment for this)
• Labs
– Include CBC, electrolytes, type and screen,
coagulation studies, and CPK, BUN, creatinine, troponin, and lactate levels (make sure
patient doesn’t develop rhabdomyolysis or
renal failure)
(e) Nonoperative treatment
• All patients are started on heparin with bolus
loading
– Heparin bolus dosing 60–80units/kg
– Followed by initial heparin infusion of
12–18units/kg/h
• IV hydration
– In preparation for the contrast load patient will
likely get from imaging (CTA) and/or
angiogram
• Stabilizing any active cardiac issues should take
precedence
(f) Operative management
• If limb is not viable, proceed with amputation as
the nerve and tissue damage is irreversible at this
point
• If limb is viable and H&P is concerning for an
embolic event, proceed with embolectomy
– Book a hybrid suite if available
– Can be performed under regional or local
anesthesia
– Prep the abdomen, bilateral groin, and circum-
ferential legs
In case the need to access the aorta/iliacs,
or make additional incisions elsewhere for
extension of clot into more distal
locations
Or harvest saphenous vein for
reconstruction
– Get proximal and distal control of the artery
along with other branches
Should administer heparin prior to clamping vessels (ACT >250)
– Perform proximal and distal embolectomy
with Fogarty balloons
Ensure strong inow and backbleeding
Be cautious with forcefully passing the
Fogarty catheters into vessels as they can
cause dissection
– Do not forget a completion angiogram
If more clots noted distally, may need additional incision distally or could give intraarterial thrombolytic agent (10mg tPA)
If concern for vasospasm, could administer
intra-arterial vasodilator (nitroglycerin or
papaverine)
If concerned for dissection ap, may need
angioplasty and/or stenting
If embolectomy fails, may need to consider
bypass procedure (although it is rarely
needed in purely embolic events)
– Check pulses post-op
• If limb is viable, and H&P is unclear for etiology,
proceed with angiography
– May need mechanical thrombolysis and/or
catheter-directed thrombolysis
Continue low-dose heparin infusion to
maintain catheter patency
Give 10mg of tPA followed by 0.5–1mg/h
infusion
Monitor brinogen, PTT every 6h
– Make sure to screen patients for any contrain-
dication to thrombolytic administration
Should perform an ECHO prior to administering thrombolytic agents systemically if
an intra-cardiac etiology is suspected due to
high risk of stroke or other embolic events
– If thrombolysis fails, may need to consider
bypass procedure
• Consider four-compartment fasciotomies for ischemia time>6h
Common Curveballs
• Recent bypass surgery
– Should investigate the graft, may need revision of
proximal or distal anastomosis.
• Post-op compartment syndrome
– Should perform prophylactic fasciotomy with longer
ischemia time.
– Should perform serial compartment checks.
– Do not delay fasciotomy if post-op development of
compartment syndrome.
• Post-op rhabdomyolysis
– Should check post-op urine myoglobin and CPK.
– Treat with IV hydration.
• Post-op acidosis, hyperkalemia from reperfusion injury
– Treat with IV hydration and calcium gluconate.
– May need HD if underlying renal disease/failure or
decreased creatinine clearance.
– Intra-op, should alert anesthesia for close monitoring.
• Know how to do fasciotomies.
• Embolus from an aortic source will need an extra-
anatomic bypass.
• Young patient will need evaluation for dissection.
117 Acute Extremity Ischemia
403
Clean Kills
• Trying to avoid the OR
– Deteriorating patients get explored.
• Not taking a fresh post-op back to the OR
– Prepare to revise or replace the graft.
• Forgetting to anticoagulate pre-op, intra-op, and post-op.
• Forgetting to check pulses pre-op.
• Forgetting to check pulses and completion angiography
post-op.
Bonus Points: Treatment Based onLocation
ofanEmbolus
• Bilateral femoral pulses absent
– Explore bilateral groins for saddle embolus.
– Prep infraclavicular area for possible extra-anatomic
bypass (axillary-bifemoral bypass).
• Unilateral femoral pulse absent
– Iliac origin (embolism or stent occlusion).
– Unilateral groin exploration.
– Prep bilateral groins to be able to perform angiogram
from contralateral side.
• Popliteal pulse absent
– Unilateral groin exploration.
– May need to expose popliteal artery for continuing dis-
tal thrombus.
• Pre-existing SFA disease
– Fem-pop is the treatment of choice.
• Previous bypass
– Prepare to expose both anastomosis.
– Likely need to revise distal anastomosis if recent.
– Vein graft may need to be replaced.
• Upper extremity
– Rarely limb threatening.
– Expose brachial artery, generally at level of anticubital
fossa.
– Low threshold for surgical exploration.
Words ofWisdom
• Acute extremity ischemia is an acute event characterized
by the “6 Ps”: pain, paresthesias, pulselessness, pallor,
paresis, and poikilothermy. Severity of symptoms often
correlates with severity of ischemia with only 6–8 h
before irreversible ischemic changes if untreated.
• One needs to act quickly to avoid having to do fascioto-
mies (will likely have to describe anyway). Pulses should
be checked bilaterally at all levels. It is critical in determining the level of the likely occlusion and planning your
operative management.
Bibliography
Fischer JE, Ellison EC, Henke PK, Hochwald SN, Tiao GM.Fischer’s
mastery of surgery. Philadelphia: Wolters Kluwer; 2019.
Porrett PM, Atluri P, Karakousis GC, Roses RE, Drebin JA.The sur-
gical review: an integrated basic and clinical science study guide.
Philadelphia: Wolters Kluwer; 2016.
Carotid Stenosis
KhaledNoueihed
118
Way Question May BeAsked?
A 53-year-old female, seen in the emergency department for
transient ischemic attack (TIA), which resolved in a few
hours after presentation, is later referred to your ofce for
evaluation of a left-sided bruit.
How toAnswer?
History
• Myocardial infarction (MI) or cardiac catheterization
• Hypertension
• Diabetes mellitus
• Hypercholesterolemia
• PAD
• History of TIA/CVA (including amaurosis fugax)
• Other sources
– Arrhythmia
– Ataxia, gait disturbances, bilateral lower extremity
weakness
– Vertebrobasilar ischemia
– Intracranial physiology
Physical Exam
• Signs of peripheral vascular disease (PVD)
• Neuro-exam to localize side
• Bruits, may have bilateral disease
• Blood pressure in both arms (to rule out aortic arch
disease)
Testing
• Noninvasive
• Carotid duplex ultrasound (US) (rst-line imaging)
K. Noueihed (*)
Department of Surgery, Thomas Jefferson University Hospital,
Philadelphia, PA, USA
• EKG
• CT or MRI head/brain (stroke)
• CTA/MRA of the neck and brain for preoperative
planning
Medical Treatment
• Focuses on management of hypertension, hyperlipidemia,
and counseling about risk factors.
• Medical management will help both lower the risk of
stroke and the operative risks if surgery is pursued.
• Management includes:
– Medical agents such as beta-blockers, antiplatelet,
statins, or other cholesterol management agents
– Counseling: blood pressure control (SBP <160), smok-
ing cessation, diabetic control, excess weight loss
Indications for Surgery
• Asymptomatic patients:
– >70% stenosis
• Symptomatic patients:
– 1 Cerebrovascular accident (CVA) or>1 TIA
50% stenosis or greater
• 100% occlusion: Do not operate.
• Timing: should be performed within 2 weeks of event
(stroke/TIA) to prevent further injury.
Stenting Considerations (Carotid Artery Stenting (CAS))
• Based on comorbidities
• Life expectancy <5years
• MI in prior 4weeks, CABG within 6months
• Congestive heart failure (CHF) with ejection fraction
(EF) <30%
• Dialysis dependence
• Severe COPD with FEV1<1.0L
• Anatomically high lesions
• Radiation-induced stenosis (CAS preferred over CEA)
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2025
M. Neff et al. (eds.), Passing the General Surgery Oral Board Exam, https://doi.org/10.1007/978-3-031-78244-2_118
405
406
K. Noueihed
Surgical Management
• Operative approach for carotid endarterectomy (CEA)
– Patient in recumbent position with head turned to
opposite side.
– Gentle prepping of the neck.
– Oblique incision along anterior border of sternocleido-
mastoid muscle.
– Divide facial vein as it comes across the level of the
bifurcation.
– Dissect out common carotid along medial border to
avoid the vagus nerve.
– Expose common carotid, internal carotid, and external
carotid to areas devoid of hard plaque.
– Determine the need for shunting (awake monitoring,
cerebral monitoring, carotid stump pressure).
– Heparin bolus before clamping.
– Clamp in disease-free areas, internal carotid artery
rst. Order of clamping should be internal carotid,
common carotid, and external carotid (ICE).
– Select shunt (safest choice on oral boards to shunt all
patients and perform under general anesthesia).
– Begin arteriotomy on common carotid artery in verti-
cal fashion and extend onto internal carotid artery.
– Back bleed shunt to free air/debris.
– Lift artery away from plaque.
– Check for loose aps; if necessary, tack with double-
arm 6-0 polypropylene with knots on the outside of the
vessel.
– Close vessel with vein patch or Hemashield patch.
– Flush all vessels before closing patch.
– Release internal carotid artery to ush debris and then
reclamp.
– Release external carotid artery rst to prevent debris/
air from entering ICA distribution.
– Drains and heparin are physician-dependent.
• The patient will have had a recent stroke (check CT brain:
if no stroke, heparin and CEA in 1week; if stroke is present, CEA in 6weeks).
• The patient will present with restenosis after CEA.
• Patient suffers postoperative MI and develops neurologic
decit in recovery room, headache, or bradycardia in
recovery room.
• The patient will have acute stroke in your follow-up of an
asymptomatic lesion
– Do not rush to operate.
– TPA if <3h from onset of symptoms.
– Administer aspirin; initiate physical therapy and CEA
in 6weeks if after 3h from onset of symptoms.
• Expanding hematoma in neck postoperatively.
• Plaque continues into the base of the skull.
• No appropriate vein to harvest.
• Postoperative hypotension/hypertension
– Nitroglycerin/nitroprusside/nicardipine drip.
– Volume and dopamine drip.
• Patient presents with nerve injury (e.g., recurrent
laryngeal).
• Management of crescendo TIAs (go to OR!).
• Patient with three-vessel heart disease and 90% stenosis
(CEA+CABG).
Clean Kills
• Not being clear on preoperative indications.
• Not discerning from vertebra-basilar ischemia.
• Operating on fresh CVA (stroke).
• Not getting cardiac workup, CTA/MRA pre-op.
• Performing blind endarterectomy (need to visualize endpoints of plaque).
• Not being able to describe methods to minimize internal
carotid artery (ICA) debris.
Common Curveballs
• Complete occlusion of common carotid artery.
• The patient will have a post-op stroke
– Examinee should obtain a stat US—likely a dissection.
• The patient will have 68% stenosis and be
asymptomatic.
• The patient will have 49% stenosis and be
symptomatic.
• The patient will present with ulcerated plaque.
Bonus Points
• Carotid endarterectomies are procedures with small
details that are important to mention when describing
operative technique.
• Steps like systemic heparinization, need for shunting, and
the order of clamping and unclamping are key details that
if not mentioned can have severe associated complications (stroke).
• Being thorough when going over the operative approach
can prevent many of the curveballs in the prior section.
118 Carotid Stenosis
407
• Many of these patients will have concomitant heart disease. If a patient needs a coronary artery bypass graft
(CABG) and has simultaneous symptomatic carotid
artery stenosis, they should undergo CEA before or concomitant with CABG.
Words ofWisdom
One common trap in these cases has to do with laterality and
localization of the injury. If a patient is found to have stenosis in the contralateral side of their stroke, this would count
as asymptomatic stenosis. These key distinctions and details
can be easily missed but can have drastic changes in the
management of the patient (medical vs surgical). Likewise,
attention to a full workup is imperative. One will be presented to a patient with a diagnosed stroke or similar cardiovascular event, but a full workup must still be performed to
ensure to rule out other causes of stroke in the evaluation of
the patient.
Important trials to review: North american symptomatic
carotid endarterectomy trial (NASCET), european carotid
surgery trial (ECST), asymptomatic carotid atherosclerosis
study (ACAS), asymptomatic carotid surgery trial (ACST),
carotid revascularization endarterectomy versus stenting
trial (CREST).
Bibliography
Brott TG, Hobson RW, Howard G, Roubin GS, Clark WM, Brooks W,
etal. Stenting versus endarterectomy for treatment of carotid-artery
stenosis. N Engl J Med. 2010;363:11–23.
European Carotid Surgery Trialists’ Collaborative Group. Randomised
trial of endarterectomy for recently symptomatic carotid stenosis:
nal results of the MRC European carotid surgery trial (ECST).
Lancet. 1998;351:1379–87.
Ferguson GG, Eliasziw M, Barr HW, Clagett GP, Barnes RW, Wallace
MC, et al. The North American symptomatic carotid endarterec-
tomy trial. Stroke. 1999;30:1751–8.
Grotta JC.Carotid stenosis. N Engl J Med. 2013;369:1143–50.
Halliday A, Bulbulia R, Bonati LH, Chester J, Cradduck-Bamford A,
Peto R, etal. Second asymptomatic carotid surgery trial (ACST-2):
a randomised comparison of carotid artery stenting versus carotid
endarterectomy. Lancet. 2021;398:1065–73.
Walker MD, Marler JR, Goldstein M.Endarterectomy for asymptom-
atic carotid artery stenosis. J Am Med Assoc. 1995;273:1421.
Visceral Artery Aneurysms
JacobWoodroof
119
Way Question May BeAsked?
Example 1 A 30-year-old pregnant female (gravida 3, para
2) presents with vague upper abdominal pain with hypotension initially that has resolved with uids. She is evaluated in
the emergency department and imaging shows 2.5cm splenic
artery aneurysm.
Example 2 A 65-year-old male with history of peripheral
artery disease presents with abdominal pain radiating into
his back; computed tomography arteriogram of the abdomen
and pelvis obtained for suspected AAA instead reveals a
1.5cm SMA aneurysm.
Example 3 For a 50-year-old female patient, you perform
an open repair of a 3 cm splenic artery aneurysm with
reversed saphenous vein graft. On postoperative day 7, she is
experiencing left upper quadrant abdominal pain and signs
of sepsis. How would you approach this patient to evaluate
for complications related to your operation?
How toAnswer?
As always, start with a thorough history and physical exam.
In terms of the patient’s presenting symptoms, most true
visceral aneurysms are asymptomatic and found incidentally
on imaging. Pseudoaneurysms, however, are generally
always symptomatic. Abdominal pain is usually nonspecic,
though pain may also present similarly to ruptured AAA
with radiation into the back. The classic presentation for ruptured splenic artery aneurysm is the “double rupture” phenomenon with rst rupture into lesser sac with subsequent
stabilization followed by a second rupture into peritoneal
cavity resulting in an acute abdomen. Superior mesenteric
J. Woodroof (*)
Department of Surgery, Thomas Jefferson University Hospital,
Philadelphia, PA, USA
e-mail: Jacob.Woodroof@jefferson.edu
artery (SMA) aneurysms may show mesenteric angina.
VAAs may also erode into the gastrointestinal tract or hepatobiliary system resulting in hematemesis, hematochezia, or
hemobilia. Conditions causing increased portal blood ow
(multiparity, portal hypertension) result in higher risk of
rupture.
• The patient in Example 1 could remain stable for complete workup and intervention, but they should be closely
monitored for “double rupture” symptomatology (acute
abdomen and signs of shock/end-organ dysfunction from
vessel target).
– It is important to be aware of rupture rates and mortal-
ity rates for splenic artery aneurysm in this patient
population (mortality with rupture is generally
10–25%, but in pregnant patients rupture mortality rate
is ~70% and fetal mortality rate is ~90%).
• The patient in Example 2 could develop subsequent
embolus to the small intestine resulting in ischemia or
perforation and ultimately require either small bowel
resection or second-look surgery.
– Understand that even though this aneurysm does not
meet the size cutoff for splenic artery aneurysms, it
still requires xation for two reasons: (1) the presence
of symptoms and (2) SMA origin.
• For the patient in Example 3, be sure to perform an interval history and physical exam, obtain vitals/labs, and
order computed tomography arteriography of the abdomen and pelvis to evaluate for splenic abscess, infected
graft, splenic infarct, or pancreatic leak.
Surgical Management
• Be familiar with the common open surgical and endovascular techniques.
– Open surgical intervention may include aneurysm
exclusion with proximal and distal ligation ± resection
of aneurysm sac. It is critical to evaluate the supplied
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2025
M. Neff et al. (eds.), Passing the General Surgery Oral Board Exam, https://doi.org/10.1007/978-3-031-78244-2_119
409
410
J. Woodroof
end organ for ischemia and perform distal revascularization when indicated.
– Endovascular options may be used if the aneurysm is
easily accessible. Methods include coil embolization
(can be used if end-organ perfusion is sufcient) or
stent grafting for exclusion of aneurysm.
• In the hemodynamically unstable patient or patient with
ruptured VAA, you should approach the patient similar to
those with AAA rupture.
– Focused history and physical exam, rapid OR
preparation.
– Permissive hypotension to allow tamponade of the
bleed.
– Type and screen; ensure adequate large bore IV access;
place urinary catheter and arterial line.
– O-negative blood, cryoprecipitate, fresh frozen plasma
to OR.
– Prep from the neck to knees.
– Can use aortic balloon for tamponade if patient is rap-
idly deteriorating.
– ICU monitoring after OR.
• Open surgical repair of splenic artery aneurysm:
– Left subcostal or chevron incision; may also use mid-
line incision.
– Access and clamp the subphrenic aorta and hepatoduo-
denal ligament if rapidly deteriorating.
– Can also use aortic occlusion balloon.
– Access lesser sac via gastrohepatic ligament.
– Expose the celiac artery and its branches.
– Obtain proximal and distal control of aneurysm.
– Enter aneurysm sac and perform bypass grafting (e.g.,
reversed saphenous vein graft) or aneurysmorrhaphy.
– Check spleen for viability.
– Evaluate for hemostasis and close in layers.
Clean Kills
• Not ruling out cardiac pathology at presentation
• Not taking a patient to the OR for an indicated VAA
repair
• Attempting endovascular therapy for ruptured
aneurysm
• Not prepping widely enough (need neck to knees)
• Not gaining appropriate proximal/distal control
• Not evaluating the supplied end organ for ischemia (e.g.,
small bowel, spleen)
• Not recognizing postoperative complications (e.g., pancreatic leak, splenic infarct/abscess)
Bonus Points
• Can approach splenic artery aneurysm from anterior or
lateral approach.
– Anterior approach via gastrocolic or gastrohepatic lig-
ament provides good exposure for proximal one-third
of splenic artery.
– Lateral approach provides good exposure for middle
and distal one-third of splenic artery.
– Lateral retroperitoneal approach after medial visceral
rotation provides good splenic artery exposure.
• Left or right medial visceral rotation may be helpful for
exposure of celiac or SMA aneurysms.
• In the rare case of an intra-organ VAA, partial resection of
that organ may be required (e.g., partial liver resection,
splenectomy, pancreatic tail resection, Whipple
procedure).
Words ofWisdom
Curveballs
• Could give you a small size (<2cm) but would need to
know which small aneurysms meet indication for repair.
• Any attempt at endovascular therapy would likely be
unsuccessful on oral board scenarios, so be prepared to
perform open repair.
• Could give multiple different aneurysms and need to gure out which you need to x.
• Could try to lead you down the path of ruptured AAA, so
it is important to have contrast imaging if able.
• For a more obscure/rare example, they could present a
large aneurysm causing compression of local structures
(e.g., celiac artery aneurysm causing compression leading
to abdominal pain, cholestasis, jaundice, or even gastric
outlet or small bowel obstruction).
• Incidence rates by aneurysm type:
– Splenic: 60%
– Hepatic: 20%
– SMA: 6%
– Celiac: 4%
– Gastric: 4%
– Jejunal, ileal, and colic: 3%
– Pancreaticoduodenal: 2%
– Gastroduodenal: 2%
• Rupture rates by aneurysm type:
– Gastroepiploic: 90%
– Hepatic: 60–80%
– Gastroduodenal and pancreaticoduodenal: 55–65%
– Splenic: 2% (25–50% during pregnancy)
– SMA: 40%
– Celiac artery: 7%
119 Visceral Artery Aneurysms
411
Bibliography
Hoballah J, Scott-Conner C, Sen Chong H.Operative dictations in gen-
eral and vascular surgery. 3rd ed. Springer; 2017.
Juntermanns B, Bernheim J, Karaindros K, Walensi M, Hoffmann
JN.Visceral artery aneurysms. Gefasschirurgie. 2018;23:19–22.
Kassem MM, Gonzalez L. Splenic artery aneurysm. In: StatPearls.
StatPearls Publishing; 2023.
Obara H, Kentaro M, Inoue M, Kitagawa Y. Current management
strategies for visceral artery aneurysms: an overview. Surg Today.
2020;50:38–49.
SCORE. https://www.surgicalcore.org/modulecontent.
aspx?id=263873.
Deep Vein Thrombosis
AmyYoung andLindseyL.Perea
Clinical Scenario 1
A 64-year-old female presents to the hospital with abdominal
pain and is found to have pneumoperitoneum on a CT scan.
She is peritoneal on exam, and you take her to the operating
room for an exploratory laparotomy and nd a sigmoid mass
with perforation and feculent peritonitis. Her pathology
results indicate colonic adenocarcinoma. On postoperative
day 3, she develops right lower extremity swelling.
120
charged. I would place the patient on 3months of therapeutic
anticoagulation for this provoked embolic event.
Prevention ofDeep Vein Thrombosis
DVT in hospitalized patients is often asymptomatic, so we
cannot rely on early diagnosis in order to prevent its complications. Therefore, prophylaxis is the best strategy to
approach the treatment of deep vein thrombosis. First we
have to understand the risk factors for DVT.
How toAnswer Scenario 1?
On this postoperative patient with risk factors for venous
thromboembolism including recent surgical intervention and
active carcinoma, I would have high suspicion for right lower
extremity deep vein thrombosis (DVT). I would take a thorough history and ask the patient if they have any history of
blood clots or easy bleeding. I would perform a thorough
physical examination including inspection of the lower
extremities, palpation of pulses, assessment for warmth and
pitting edema, and evaluation of Homan’s sign. I would order
a venous ultrasound of the right lower extremity to assess for
major venous clot. If there is evidence of venous thromboembolism, I would place the patient on therapeutic anticoagulation, starting with a heparin drip and progressing to oral
anticoagulation like apixaban or rivaroxaban once she is dis-
A. Young
Department of Surgery, Philadelphia College of Osteopathic
Medicine, Philadelphia, PA, USA
e-mail: Amyyo@pcom.edu
L. L. Perea (
Department of Surgery, Philadelphia College of Osteopathic
Medicine, Philadelphia, PA, USA
Division of Trauma and Acute Care Surgery, Department of
Surgery, Penn Medicine, Lancaster General Hospital,
Lancaster, PA, USA
e-mail: lindsey.perea@pennmedicine.upenn.edu
*)
• Obesity, major medical illness, cancer, age >60, pro-
longed immobilization, lower limb paralysis, use of hormonal therapy, stroke, congestive heart failure, or recent
MI, inherited coagulopathies including protein C or S
deciency and factor V mutation, antiphospholipid antibody syndrome.
• Major surgeries including orthopedic surgery of the lower
limbs, surgery for cancer, and neurosurgery, acute spinal
cord injury, and multi-trauma.
There is a risk stratication system for patients undergo-
ing surgery based on age and presence of other risk factors.
Incidence
of fatal PE
(%)
Level of
risk Dening factor
Low Minor surgery in
patient <40
without risk
factors
Moderate Minor surgery in
patient with risk
factors
Minor surgery in
patients 40–59
without risk
factors
Major surgery in
patients <40
without risk
factors
Incidence
of DVT
(%)
2.5 0.2 0.002
12–25 1–2 0.1–0.4
Incidence
of PE (%)
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2025
M. Neff et al. (eds.), Passing the General Surgery Oral Board Exam, https://doi.org/10.1007/978-3-031-78244-2_120
413
414
A. Young and L. L. Perea
Incidence
Level of
risk Dening factor
High Minor surgery in
patients >60
Major surgery in
patients >40
with risk factors
Highest Major surgery in
patients >60
Major
orthopedic
surgery
Spinal cord
surgery
Trauma
Source: O’Donnell and Weitz (2003), Canadian Journal of Surgery
of DVT
(%)
25–50 2–4 0.4–1.0
50–70 4–10 0.2–5.0
Incidence
of PE (%)
Incidence
of fatal PE
(%)
Based on this risk stratication system, low-risk patients
do not require prophylaxis other than early mobilization.
Moderate- to high-risk patients can be given unfractionated
heparin or low molecular weight heparin and should get
intermittent pneumatic compression.
Methods ofProphylaxis
• There is evidence to show that there is no signicant difference between 3 and 6 months of therapeutic
anticoagulation.
VTE Prophylaxis and Colon Adenocarcinoma
• While hospitalized, patients with colon adenocarcinoma
should receive enoxaparin standard dosing of 40mg daily
as is standard in postoperative patients.
• Patients with colon adenocarcinoma should be given a
28-day prophylactic regimen of 40mg enoxaparin daily
upon discharge from the hospital (Perrotti etal. 2020).
• The patient in our scenario is covered with her oral anticoagulation that she received for her provoked DVT.
• Ensure appropriate dosing for morbidly obese patients
with BMI >40 at 40mg BID of enoxaparin.
Clinical Scenario 2
A 36-year-old male presents to the trauma bay after an
MVC.He is diagnosed with fractures of his right-sided ribs
3–8. On hospital day 4, his pain is still uncontrolled. You
determine that the patient is an appropriate candidate for rib
plating. Describe strategies to control his pain perioperatively and how these strategies would affect any anticoagulation the patient may have.
Mechanical
• Compression stockings
• Intermittent pneumatic compression
– Should be used on all patients during surgical case if
possible
Chemical
• Unfractionated heparin (Anderson etal. 2019)
– Lowers dose of DVT from 25% to 8% (O’Donnell and
Weitz 2003)
– Contraindications: active bleeding, heparin-induced
thrombocytopenia (HIT)
• Low molecular weight heparin
– Similar reduction of DVT
– Lower risk of HIT
– More expensive
– Contraindications: active bleeding, HIT, epidural cath-
eter, intracranial pressure monitor, external ventricular
drain (Rumbaugh and Schmidt 2018)
– Should not be used in patients with renal failure
Treatment of Venous Thromboembolism (Kearon and
Akl 2014)
• The duration of treatment for a rst-time, provoked calf
DVT is 3months of therapeutic anticoagulation.
• If anticoagulation is stopped before the 3-month course is
complete, the patient is at a high risk of recurrent DVT.
How toAnswer?
This is a trauma patient with a signicant injury; therefore
he meets criteria for DVT prophylaxis while he is admitted to
the hospital. I would place him on prophylactic enoxaparin
daily for deep vein thrombosis. For his pain, I would start
with PRN opiates like morphine or Dilaudid. I could progress to a Dilaudid PCA if the as-needed medications are not
controlling his pain. Before his rib plating, I would ask anesthesia to place a thoracic epidural catheter. For this, the
Lovenox prophylaxis must be held for at least 12h before the
procedure; however I would confer with my anesthesia colleagues and hold the prophylaxis for 24h if possible.
DVT Prophylaxis andDosing
• This patient is at high risk for DVT given his medical
comorbidities and current inammatory condition.
• You would recommend placing the patient on either
weight-based subcutaneous heparin every 8h or weightbased low molecular heparin once daily (Rumbaugh and
Schmidt 2018).
– Heparin dosing: 5000units q8hr