Interesting Case Rounds

Rebecca Burton-MacLeod

R4, Emergency Medicine

Aug 3, 2006

History

• 81M• CC: numbness in left arm and SOBOE• HPI: symptoms started suddenly while pt

was swimming 4hrs earlier– “clumsiness” in L arm– Diaphoretic, dizzy– 2d hx of SOBOE– No specific chest pain

History cont’d

• No palpitations

• No headache

• Normal left leg function, normal speech/ vision

• No previous similar symptoms

PMHx

• Paroxysmal Afib• Pacemaker x 10yrs• Angina 20yrs prior• CHF• Scrotal hernia• BPH and TURP

• Meds:– Lasix

– Warfarin

– Fosinopril

– Bisoprolol

– Taking all meds regularly

On exam:• Vitals: Afebrile, P 105 irreg, BP (R arm) 152/80, R

23, sats 92% r/a• Normal HS, no murmurs• JVP ~3cm ASA, mild bilateral pitting edema to LE• Lungs—dec A/E to R base• Abdo—soft, non-tender• Neuro—CN normal, normal tone, power, reflexes;

sl decreased sensation entire L arm• MSK—no bony tenderness L arm, full ROM

Any thoughts ?

Investigations ?

• CBC, lytes, Cr, INR/PTT, TNT (4hour)

• EKG

• CXR

Test results

• Normal CBC

• Normal lytes, Cr

• TNT negative

• INR 1.2

• EKG—Afib, T wave inversion in V4-6 (new compared to previous EKG)

CXR

Any further thoughts ?

Management ?

Case cont’d

• No signif improvement

• Continues to c/o “clumsiness” in L arm

CT head

Re-examine pt

• C/o coolness in L arm

• Decreased radial/brachial pulses in L arm

• Pt had presented to ED ~1mo ago with epistaxis– Nose packed– Vit K given to reverse warfarin (INR >9)

CT angio

• “saddle-like” intraluminal filling defect in L main PA with extension filling L upper lobe arterial branches

CT angio 14.5cm L distal axillo-brachial artery occlusion

Problem list

• CHF

• Afib

• PE

• L ischemic arm

• Low INR

Management

• Pt admitted to Vascular service

• Heparinization started

• Pt underwent L brachial embolectomy the following day

• Long term anticoagulation (with close monitoring to ensure therapeutic INR !)

Acute upper limb ischemia

Acute upper limb ischemia

• Is far more uncommon than lower limb ischemia– Upper extremity has good collateral circulation and low

rate of atherosclerosis

• Responsible for ~15% of vascular procedures for ischemic limbs

• Of all embolization sites, upper extremity cases accounts for only 8%

• Functional limb impairment occurs in ¾ of cases if left untreated

Upper extremity anatomy

Causes • Main causes of upper limb ischemia:

– Thromboembolic disease– Traumatic injuries– Aortic dissection – Atherosclerosis and chronic limb ischemia– Subclavian steal s/o– Thoracic outlet s/o– Iatrogenic causes

Upper limb ischemia

Ali, T et al. Vasc Surg. 2001.

Thromboembolic events

• 62% of pts have associated Afib

• 84% have associated CAD

Differentiation of Thrombus vs. Embolus

• Embolus– Usual identifiable source

for embolus (Afib)

– Rarely hx of claudication

– Few findings suggestive of occlusive disease

– Sharp demarcation of ischemia

– Minimal atherosclerosis, sharp cutoff, few collaterals on arteriography

• Thrombus– Less common to find

identifiable source for embolus

– Often hx of claudication– Often findings suggestive of

occlusive disease (contralateral limb pulses diminished/absent)

– Diffuse ischemia– Diffuse atherosclerosis,

tapered irregular cutoff, well-developed collaterals on arteriography

Rosen’s. Ch 82.

Diagnosis

• 5 P’s:– Pain– Pallor– Pulselessness– Paresthesias– Paralysis

Rutherford ClassificationRutherford Classification

____CompleteCompleteCompleteCompleteAbsentAbsentPrimary Primary amputation req.amputation req.

IrreversibleIrreversibleIIIIII

AudAud__PartialPartialPartialPartialSlow/absentSlow/absentSalvagableSalvagable if if treated treated emergentlyemergently

ThreatenedThreatenedIIbIIb

AudAud__PartialPartial--Intact/slowIntact/slowSalvagableSalvagable if if treatedtreated

ThreatenedThreatenedIIaIIa

AudAudAudAud----IntactIntactNot immediately Not immediately threatenedthreatened

ViableViableII

VVAASensory Sensory lossloss

ParalysisParalysisCap. refillCap. refillDescriptionDescriptionCategoryCategory

DopplerDoppler

Acute limb ischemia

Management

• For limb-threatening ischemia:– Emergency Fogarty catheter embolectomy– +/- vascular bypass grafting if in situ

thrombosis as cause of ischemia– If above measures fail, then primary amputation

Heparin ?

• Should be started immediately

• 80U/kg IV bolus, then 18U/kg/h maintenance infusion

• Minimizes clot propagation and obviates further embolism

• No formal studies done to establish beneficial role

GP IIb-IIIa antagonist ?

• Pilot trial randomized 70 pts to urokinase + abciximab vs. urokinase + placebo– Amputation-free survival at 90d was 96% with

GP IIb-IIIa group vs. 80% with placebo– More rapid thrombolysis in first group, but also

higher rate of non-fatal major bleeding

Thrombolysis ?

• May be considered in non-limb-threatening ischemia (takes 6-72h for effect)

• Therefore, most useful if known thrombosis

• IV thrombolysis initially used, but now mostly replaced by catheter-directed thrombolysis

Thrombolysis ?

• One trial comparing IA streptokinase, IA rt-PA, and IV rt-PA– Angiographic success rates 80% vs. 100% vs.

45%– 30 day limb salvage rates 60% vs. 80% vs. 45%

respectively

• Comparison of rt-PA with urokinase showed faster lysis with rt-PA but 24h and 30d clinical success rates were similar

Clogett GP et al. Chest. Sept 2004.

Surgery vs. thrombolysis

• Cochrane Review 2006.– 5 trials with 1283 participants– No signif difference in limb salvage or death at

30d, 6mos, 1yr– Thrombolysis was significantly associated with

higher stroke rates (1.3%), major hemorrhage (8.8%), distal embolization (12.4%)

– Concluded insufficient evidence to advocate for universal initial treatment

Case conclusion

• Pt felt to have developed thromboembolic disease resulting in L ischemic arm and PE– Likely due to subtherapeutic INR– ? Due to epistaxis and vitamin K administration

Vitamin K to reverse anticoagulation

DeLoughery TJ et al. Crit Care Clin. July 2005.

Questions ?