Surgery E2: Vascular/Adrenal

What is the role of the adventitia (outer layer) of blood vessels?

provides structural support and shape

What is the role of the middle layer (tunica media) of blood vessels?

composed of elastic and muscular tissue to regulate the diameter

What is the role of the inner layer (tunica intima) of blood vessels?

composed of endothelial lining to allow frictionless movement of blood

What are arteries made up of?

elastic tissue and less smooth muscle

What are arterioles made up of?

smooth muscle

What are capillaries made up of?

thin-walled → single endothelial layer

What occurs in the venules?

exchange of oxygen and nutrients

What are veins made of?

less smooth muscle and less elastic; bigger ones have valves

What are RF for ASCVD?

hypercholesterolemia, HTN, DM, smoking, obesity, M > 45 yo, F > 55 yo, strong FH

What are sx of ASCVD?

angina, CP, exertional dyspnea, syncope, LE edema, orthopnea

Unstable plaques that rupture can cause what?

MI or CVA

How do you screen of PAD?

doppler to measure ABI

What is the gold standard dx test for CAD?

cardiac cath

*FFR <0.75 is associated w/ myocardial ischemia

What does a CCTA coronary computed measure?

calculates Coronary calcium scores and location of blockages

What is the tx for ASCVD?

lifestyle: cease smoking, wt loss, healthy diet

pharm: statins, ACEI, ARBs, diuretics, BB, CCB

surg: PCI or CABG

How is a PCI done?

access via femoral or radial artery → cath advanced to ascending aorta → IV contrast is introduced to visualize the anatomy → can implant stent if needed

Which type of PCI removes the blockage by cutting or laser (followed by balloon and stent)?

atherectomy

What type of PCI uses pulsatile mechanical energy to break up the plaque deposit?

shockwave lithotripsy

What is a CABG for?

bypasses blocked coronary arteries to restore blood flow to ischemic myocardium

What conduits are used as bypass grafts?

L internal mammary arter (LIMA), saphenous vein graft (SVG), R internal mammary artery (RIMA), radial artery, gastroepiploic artery

What are the 2 types of CABG?

On-pump: bypass circuit to stop heart, allows for a bloodless field

Off-pump: beating heart surgery, uses sternotomy approach

What characterizes a true aortic aneurysm?

all 3 layers of the vessel wall are involved (> 1.5x normal size)

What is the MC aortic aneurysm?

infrarenal AAA

What are RF for aortic aneurysms?

smoking, advanced age, M > F, HTN, hypercholesterolemia, CTD (Marfan’s, Ehlers Danlos)

When surgery done for aortic aneurysms in pts w/ Marfan’s?

earlier than 5 cm

What is a Saccular (berry) aortic aneurysm?

outpouching; affects part of the arterial circumference

*higher risk of rupture!!

What is a Fusiform aortic aneurysm?

diffusely dilated; symmetrical enlargement involving the whole circumference of the artery

What is a pseudo aneurysm?

only involves the outer layer (adventitia)

What are sx of aortic aneurysms?

asx found incidentally, non-tender pulsatile abd mass, ± flank, abd, back pain

*rupture is life-threatening!!

What testing is done for aneurysms?

US for screeing; CT abd/pelvis or MRI

When is surgery recommended for aortic aneurysms?

M: 5.5 cm, F: 5 cm OR inc in size or sx

rapidly enlarging (>0.5 cm over 6 months or 1 cm in 12 months)

What is the preferred surgical approach for aortic aneurysm?

Endovascular approach via femoral artery

What are the disadvantages of open repair for aortic aneurysms?

dec pulm function post-op, renal & intestinal ischemia, more difficult access to intraperitoneal contents, higher mortality rate

What is the standard of repair for most aneurysms?

Endovascular grafting (introduced via femoral artery)

What are advantages of endovascular grafting?

dec peri-op mortality, dec blood loss, dec hospital stay, more rapid return to normal activity

What are disadvantages to endovascular grafting?

need for regular follow up, graft may need surgical correction, inc renal dysfunction secondary to contrast dyes used

What causes aortic dissection?

tear in intimal layer allows blood to enter between the intima and media → dissects the layers and a flap develops

What are the mortality rates w/ emergent open repair of aortic dissections?

40-70%

*survivors have inc rate of renal dysfunction, MI, CVA

What are sx of aortic dissection?

sudden midabd/flank pain, severe acute “tearing” CP, shock, pulsatile abd mass, syncope, hypovolemia, wide pulse pressure

What would be seen on a CXR or abd-XR of an aortic dissection?

widened mediastinum, ± pleural effusion, esophageal deviation, tracheal deviation

What imaging is used to evaluate aortic dissection?

CXR, CTA or MRA (used to plan surgery), US

spiral CT w/ contrast → can quickly detect location (CT or MRI w/ 3D imaging is most precise)

What is the tx for aortic dissection?

aggressive IV fluid & blood resuscitation, maintain systolic BP ~70-80 mmHg

EMERGENCT surgical repair

What are RF for PAD?

hypercholesterolemia, HTN, cigarette smoking, DM

What are sx of aortoiliac dz?

pain occurs in thigh and buttock muscles

What are sx of femoropopliteal dz?

occurs below the inguinal ligament → pain occurs in calf muscles

*MC site is distal superficial femoral artery

What are the sx of tibial occlusive dz?

occurs below popliteal trifurcation → loss of pulses, pallor, cool, cyanotic, muscle atrophy, loss of hair

Who is tibial occlusive dz common in?

DM, ESRD, advanced age

What is Buerger’s sign?

*indicates PAD

reactive hyperemia after dangling a pt’s foot

What is an abnormal ABI?

*ABI = ankle systolic / brachial systolic

< 0.9

0.5-0.8: moderate; < 0.5 = severe

What is a normal ABI?

1-1.4

Who does Leriche syndrome occur in?

men w/ aortoiliac disease

What are sx of Leriche syndrome?

claudication of thigh & buttock muscles, impotence, dec or absent femoral pulses, possible transient numbness of extremity

What is the tx for PAD?

manage RF, inc exercise, foot care, pharmacy: ASA or clopidogrel, for intermittent claudication: Pentoxifylline, Cilostazol

What is the surgical tx for PAD?

endovascular sugergy: PTA, percutenous atherectomy, arterial bypass

*gangrenous tissue → amputation

What causes acute arterial occlusion?

thrombosis from preexisting PAD, arterial emboli from another site, penetrating & blunt trauma, thrombosis of a pre-existing arterial aneurysm

What are sx of acute arterial occlusion?

6 P’s -pallor, pain, paresthesia, paralysis, pulselessness, poikilothermia

*occurs distal to the occlusion

What is the tx for acute arterial occlusion?

IV heparin, STAT thrombo or embolectomy, endarterectomy, surgical bypass, fasciotomy

What makes up the majority of strokes?

85% ischemic -MCC arteriosclerotic heart disease

What are RF for CVA?

HTN, Afib, DM, smoking, obesity, drug use

What is the workup for a CVA?

STAT non-contrast head CT

US for carotid

ECHO to find etio

What is the tx for CVA?

IV tPA (alteplase) w/in 4.5 hrs

*carotid bifurcation → carotid endarterectomy w/ stent

How do DVTs present?

u/l edema, pain, + Homan’s

How much does surgery inc risk of DVT

21-fold

What workup is needed for a DVT?

duplex US, D-dimer, PT/INR, PTT

What is the tx for DVT?

prevention: compression devices, early ambulation

Pharm: LMWH, Factor Xa inhibitors, unfractionated Heparin

What are primary varicose veins?

superficial vein involvement only, genetic or developmental defects in the vein wall

What are secondary varicose veins?

arise from destruction/dysfunction of valves d/t: trauma, DVT, AV fistula, nontraumatic proximal venous obstruction (pregnancy, pelvic tumor)

What are RF for varicose veins?

F, pregnancy, FH, prolonged standing -job, hx phlebitis

What are sx of varicose veins?

leg heaviness & fatigue after prolonged standing, night cramps, ± ankle edema, itching skin discoloration

What is the workup for varicose veins?

duplex US

What is the tx for varicose veins?

nonsurg 1st: leg elevation, elastic support hose, regular exercise

What are indications for surgery tx of varicose veins?

persistent or disabling pain, recurrent superficial thrombophlebitis, erosion of overlying skin, manifestations of chronic venous insufficiency

What are the ablation techniques for varicose veins?

Thermal: radiofreauency ablation, endovenous laser tx

Chemical: injection sclerotherapy

What causes chronic venous insufficiency?

direct result of venous HTN

*deep vein valve incompetence, venous obstruction, reflux

What are sx of chronic venous insufficiency?

chronic edema, hyperpigmentation, venous ulceration (malleoli), liperodermatosclerosis (end stages)

What workup is done for chronic venous insufficiency?

venous duplex US, MRI or CT venogram

What is the tx for chronic venous insufficiency?

leg elevation, regular exercise, elastic compression stockings

Surgery: not 1st line d/t high recurrence → valvuloplasty, sclerotherapy, endovenous thermal ablation

Which ports are external?

PICC lines, central venous catheters (Hickman), Prosthetic grafts

What ports are internal?

AV fistula, peritoneal dialysis catheter, implanted ports

What are PICC ports for?

give IV meds, draw blood for labs

*in upper arm, vein just about antecubital space, guided into chest

What should you get after placing external ports?

CXR

What are complications of placing external ports?

pneumothorax, hemothorax, arterial injury, bleeding, nerve injury, thrombosis, infections

What are prosthetic grafts?

SQ placed prosthetic material necessary in pts w/ poor peripheral veins

*complications: hemorrhage, thrombosis, occlusion, infection

What are AV fistulas?

connections btwn arteries and veins for hemodialysis

*complications: failure to mature (enlarge to usable diameter), aneurysms, thrombosis

What are peritoneal dialysis catheters?

placed for peritoneal dialysis

*advantages: include pt mobility and pt satisfaction, few dietary restrictions, no system anticoagulation

What are CI for peritoneal dialysis catheter?

obliteration space from previous surgery, inadequate peritoneal clearance, lack of diaphragmatic integrity

What type of needle do Implanted venous access (lumen) ports require?

Huber needle

What are indications for an adrenalectomy?

adrenal tumors, Cushing’s (MCC pituitary adenoma), Pheochromocytoma

What are sx of a Pheochromocytoma?

HA, tachy, palpitations, diaphoresis, CP, anxiety, HTN

What intra-op meds are need during an adrenalectomy for pheochromocytomas to avoid a HTN crisis?

alpha blockade (phenoxybenzamine) THEN beta blockade (phentolamine)