Acute Limb Ischemia Flashcards
Classic signs of ALI
6 P’s:
Pain
Pallor
Pulselessness
Paralysis
Paraesthesia
Perishingly cold
Rutherford classification
I: viable
II: threatened
a (marginal): minimal sensory
b (immediate): sensory + motor deficit
III: irreversible
Parameters of Rutherford classification
Capillary refill
Sensory Loss
Muscle paralysis
Doppler sign
Embolic causes of ALI
Cardiac:
-AF
-post MI mural thrombus
-CRHD
Atherosclerotic plaque
Proximal aneurysms
Thrombotic causes of ALI
Atherosclerosis
Popliteal aneurysm
Bypass graft occlusion
Stent occlusion
Thrombotic conditions
Other (non-embolic/thrombotic) causes of ALI
Trauma/Iatrogenic
Aortic dissection
Drug use
Popliteal entrapment
Cystic adventitial disease
External compression
Compartment syndrome
TOPAS trial
Multicenter RCT comparing Surgery vs intra-arterial thrombolysis in acute lower limb ischemia
NO difference in amputation free survival (6m, 1y) and overall survival
Evidence of surgery vs intra-arterial thrombolysis
New York study
TOPAS
STILE
Conclusion: both effective
Indications for intra-arterial thrombolysis
Acute lower limb ischemia
Bypass graft thrombosis
Endovascular complications
Contraindications for IAT
Active bleeding (absolute)
Known pregnancy
Stroke/TIA within 2 months
Craniotomy within 2months
Vas/abd surgery within 2 weeks
Puncture of non-compressible vessel/bx within 10 days
Previous GIB
Trauma within 10 days
Agents for IAT
Urokinase
r-TPA (tissue plasminogen activator)
Streptokinase (rarely used due to anaphylaxis)
Predictors of failure for IAT
Multilevel disease
DM
Age
Female
Failure of guide wire traversal
Management for compartment syndrome
Emergency double incision fasciotomy
Landmarks for double incision lower limb fasciotomy
Anterolateral incision: 2cm anterior to fibular shaft
Posteromedial: 2cm posterior to medial border of tibia
Ischemic-reperfusion injury
1) pathophysiology
2) toxic metabolites
3) manifestation
1) bloodstream carries toxic metabolites to the parts of body
2) K, PO4, Lactic acid, Myoglobin, CK
3) AKI, DCI, SIRS
Treatment of myoglobinuria in ischemic repercussion injury
NaHCO3 for alkalinization of urine
Emergency hemodialysis
Modifiable risks for atherosclerosis
Smoking
DM/Glycemic control
HT
HL
Renal disease
High homocysteine levels
Hypercoagulability
Non-modifiable risks for atherosclerosis
Age
Gender
Ethnicity
Definition of Peripheral arterial disease (PAD)
atherosclerosis leads to arterial stenosis and occlusion of major vessels supplying the lower extremities
Intermittent claudication
Reproducible ischemic muscle discomfort in lower limb by exercise, and relieved by rest within 10 minutes
Pre-operative preparation for embolectomy
- Rehydration
- O2 therapy
- Heparin injection
- 5000 units or 80 units/ kg
- LA under MAC
- Prep:
- Heparin saline
- Fogarty catheter (Fr3,4,5)
- Radiolucent XR table
- Doppler USG
What is the incision for embolectomy?
Vertical incision directly over femoral pulse at midpoint between pubic symphysis and ASIS
How to perform a femoral embolectomy?
- Vertical incision over groin centered over CFA
- Double sling CFA, SFA, PFA
- Transverse arteriotomy in origin of CFA just above PFA
- Fogarty ballon Fr 4/5 for proximal trawl, Fr 3 / 4 for distal trawl until good flow and back bleeding
What are potential problems with just femoral approach?
- Anterior tibial artery clots missed
- May need popliteal exploration for three lower limb vessels
What type of sutures are used for vascular repair?
Monofilament
Synthetic (Non-absorbable)
Double-armed
