Spinal Cord Stimulation for SeverelyIschemic Limbs

CARLOS TULIO SAMPERE. JORGE ALBERTO GUASCH, GARLOS MARIAPALADINO. MANUEL S A N C H E Z G A S A L O N G U E , andBENJAMIN ELENGWAJG

From the Department of Vascular Surgery, Cardiovascular School Cosme Argerich Hospital,Buenos Aires, Argentina.

SAMPERE, C.T., ET AL.: Spinal cord stimulation for severely ischemic limbs. Severe atherosclerosis ofthe lower limbs causes rest pain, skin ulcerations and gangrene. In such situations and when standardsurgical treatment had failed or it is impossible to employ, spinal cord stimulation (SCSJ seems to he ofvalue. Since April 1985, we have used this technique on 19 patients. The results have been beneficial in70.6% of the cases and have shown some evidence of increasing cutaneous flow. However, randomizedseries are required before accepting it as having a special place in the fight against atherosclerotic disease.(PACE, Vol. 12, February 1989}

atherosclerosis, severe ischemic, spinal cord stimulation

Introduction

The rate of blood flow to the tissues of anypart of the body is determined by the head ofpressure driving blood through it and the sum ofthe resistances of the vasculature of tbe part. Thefollowing formula from Pouiseuille's law ex-presses tbese relationsbips in a simple formwhere Q is the flow. Pa and Pv tbe arterial andvenous pressures, Rf and Rp the functional andpatbological resistances.'

Q =P a - P v

Rf + Rp

Any tberapeutic measure to be effective musteither increase the pressure gradient perfusingthe iscbemic part or decrease the resistances. Tbeformer is achieved easily with a successful bypassand the latter may be obtained witb sympathec-tomy, vasodilator drugs and more recently withspinal cord stimulation (SCS).̂

Address for reprints: Dr, C.T. Sampere. Cosme Argerich Hospi-tal, Alte. Brown 240 (1155) Buenos Aires. Argentina.

Received October 7. 1988; accepted October 10, 1988.

This technique has been employed in angio-spastic diseases or in atherosclerosis when thereare obstacles for direct revascularization.^ •* Tbepurpose of tbis article is to present preliminaryobservations on 19 patients who received SCS.

Material and Methods

From April 1985 to July 1987, 19 patientswere selected to be treated by SCS (Tables I and IIsummarize the clinical data). Tbe average age was69 and tbere were 17 men and two women. All ofthem had a severe chronic iscbemia due to atb-erosclerotic symptomatic disease. Nine were dia-betics, four bad coronary disease, and tbree badsuffered cerebrovascular disorders. All of the pa-tients complained of either intermittent or perma-nent rest pain. Moreover, they suffered from skinlesions in several forms and sizes (Table II). Insome cases skin lesions were small (#3, 6, 8, 13,15, 16) but in others (#7, 9, 10, 11, 12, 18) lesionsspread over a wide area of soft tissues and fourcases (#2, 4, 7, 12) had digital gangrene.

All patients bad signs and symptoms that sta-bilized at least 6 months before tbe study. All butone patient had given up smoking. Angiograms

PACE. Vol. 12 February 1989 273

SAMPERE, ET AL.

PatientNumber

2346789

10111213141516171819

Age

5674618054797777706457706471115585

Patients

Sex

MM

LJ.

MMMFMMMMMFMMMM

Table 1.

Treated with SCS

Diabetes

YesYesYesYesNoNoYesNoYesYesNoYesNoNoNoNoNo

Previous V.Surgery (N")

23

——1

——1

—13

——112—

VascularOcclusion

f.p.t.f.p.t.t.f.p.t.f.p.tf.p.t.f.p.tt.f.p.t.f.p.t.f.p.t.f.p.t.f.p.t.f.p.t.f.p.t.f.p.t.f.p.t.

f.p.t.: femoro popliteal tibialt.: tibial

were performed in all of them; in 17 patients vas-cular surgery was considered impossible and intwo the prognosis was poor. Prior direct vascularsurgery had failed in nine patients, three of whomhad had lumbar sympathectomy.

Systolic blood pressures ofthe first toe, ankleand arm were measured by Doppler technique.

When possible, walking time was assessed ona treadmill at 2 mph up a 12% grade. These stud-ies were repeated every 3 months during the pe-riod of follow-up. Last year we began to use laserDoppler velocimetry. The probe was placed on atoe and capillary flow was continuously recordedduring 3 to 5 hours. Furthermore, changes during"gasp" and Valsalva maneuver were investi-gated.^ Capillary pulse reappearance was also as-sessed after 3 minutes occlusion by a cuff justbelow the knee.

The stimulator implant (Itrel, TM; Medtronic,Minneapolis, MN, USA.) was carried out in twostages separated by a trial period: (a) Lead im-plant: it was inserted percutaneously and a moni-toring cable was left connected to a temporarypacemaker. The trial period usually lasted from 3

to 7 days and the decision to internalize was basedupon the extent of pain relief, signs of flow in-crease, if any, and patient acceptance of stimula-tion; (b) Internalization: the pulse generator wasplaced in a subcutaneous pouch. There was nopain relief in two cases during the trial period andthe pulse generator was not implanted (#1 and 5).The follow-up ranged from 2 to 27 months.

Results

We classified the SCS results as: (a) null; (b)good or (c) excellent. We define these terms as:null: when there is neither pain relief nor lesionimprovement; good: when symptoms decrease75% and skin lesions improve; excellent: whensymptoms and signs disappear.

In five patients the results were null (TableIII], three of them underwent major amputationsduring the follow-up period and in one patient asaphenous bypass to an isolated popliteal arterywas performed successfully as a last resource forlimb salvage. The last one died from a stroke.Nine patients had good results (Table IV). Two

274 February 1989 PACE, Vol. 12

SPINAL CORD STIMULATION

Patient

234

6

7

8

910

11

12

13141516171819

Rest Pain

IntermittentPermanentPermanent

Permanent

Permanent

Permanent

PermanentPermanent

Intermittent

Permanent

PermanentIntermittentIntermittentIntermittentPermanentPermanentPermanent

N

(3)(2)(2)(1)

(3)

0)(1)

(3)

( - )

(1)(1)(1)(1)

Table II.

Characteristics of the Patients

Ulcers

1.4. 12.91.40.1

—

0.33,0.53611.51. 1.5

61510.1

—30

—

Gangrene

Vtoe—

Ill toe

—

II toeIII toe + Mt.

—

——

—

IV toeV toe + Mt.

——————

1 toe

B.P. toe

25—40

20

—

20

40

—

45

30505045———

A/AI

0.350.310.35

0.61'*'

0.30

0.61***

0.300.35

0.37

0.35

0.360.400.430.30

—0.410.27

Photop.Waves

YesNoNo

No

No

No

NoNo

No

Yes

YesNoYesNoNoYesNo

B.P. toe: blood pressure toe; A/A I: ankle/arm index; ('): calcified arteries; Mt.: metatarsal; Photop. Waves:Photopletismographic waves.

died from cardiac disease, and one after colonicsurgery. The results were excellent in three cases(Table V) including one who suffered the ampu-

tation of two toes. In four patients walking timeincreased 5 to 8 minutes over the preceding dura-tion.

Patient

7

91 0 "

11

12

Pain Relief

25-50%

0-25%50-75%

25-50%

0-25%

Table III.

"Null" Results

Ulcer Gangrene

•

*

^^ •

Follow Up (months)

Above knee 2Amputation+ Stroke 3Above knee 7AmputationIsolated popliteal 5BypassAbove knee 2Amputation

no change* progressed to femoropopliteal occlusion

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SAMPERE, ET AL.

Patient

3468

1 3 "14171819

Pain Relief

75-100%75-100%75-100%75-100%75-100%75-100%75-100%75-100%75-100%

Table IV.

"Good" Results

Ulcer Gangrene

healing —healing *healing —healing —healing —healing —

— —healing —

*

Follow Up (months)

+ Myocardial infarct. 14+ Arrhythmias

AliveAliveAliveAlive

+ Colonic surgeryAliveAlive

3181788332

no change' redo 6 months

There were no changes of the ankle, arm andtoe pressure. Two out of four limbs where photo-plethismographic waves were able to be obtainedshowed a slight increase in this measurement.These results were best recorded from the contra-lateral limb that was usually less affected (Fig. 1).

No variation was registered with laserDoppler velocimetry (#16,17,19) neither in capil-lary flow nor during "gasp" and Valsalva maneu-ver, however, increase in capillary pulse reap-pearance time was observed in these three casesafter 20-30 days of SCS (Fig. 2). This new testseems to be of value, although further research isneeded before accepting it as reliable.

Discussion

SCS was beneficial in 70.6% of the cases, andthese results are similar to those of Augustinson.^Although SCS was not useful in the remaining29.4% of the patients, we can expect a decrease,

because according to Broseta'* we now indicatethis procedure to patients whose ulcers are lessthan 3 cm^ and whose digital gangrene is limitedto one or two toes.

One of the main demonstrated advantages ofSCS has been pain relief^ •"'" while healing of le-sions by vasodilation occurs slowly in atherio-sclerotic patients^ •* as was observed in our cases.

It is not known whether the pain relief andautonomic effects are due to the same mechanismor if they are two different actions.^ We couldshow some evidence of flow increase as wasmentioned above. In angiospastic disorders andvasculitis the results are better.^•''•'"

In 1986, we treated a Martorell ulcer by thisprocedure.^' The patient is in his 25th month offollow-up and recurrence of the lesion bas notoccured.

SCS may improve blood perfusion through (a)sensory masking, (b) vasoconstrictor blockage, or(c) antidromic vasodilation. Prostagiandin release

276

Patient

2

1516

* healing

Pain Relief

100%

75-100%100%

Table V.

"Excellent" Results

Ulcer Gangrene

— IV-V toeResection"

healed —healed —

February 1989

Follow Up

Alive

AliveAlive

(months)

26

66

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SPINAL CORD STIMULATION

a.

M b *

Ml*.

F.R. (2t

b .

without tUmulatlon

Uff

Figure 1. Increase of pholoplethismographic waves, a) Affected iimb; h) Contralaterai Jimb.

may play a role in skin blood flow but the sympa-thetic trunk is not essential for arterial dilation.^^The decrease of photoplethismographic waveswhile voltage output is increased, as found inthree cases would support the first theory (a)(Fig. 3).

Recently a very interesting article by Riverset al." has shown in a similar group of patients(without measuring the ankle, toe and arm pres-sure) healing of lesions and sustained improve-ment over long periods only with conservativetreatment. We agree with them because we have

PACE, Vol. 12 February 1989 277

SAMPERE, ET AL.

27/1/87 preoperatlve

v.O. 3*1 3.5'

B.L (16)

•4

V.O.- vascular occlusion

Figure 2. Capillary pulse reappearance time (Laser Doppier).

Figure 3. The decrease of pbotopletismographic waves while voltage output is increased.

observed several of these cases and because ofthis we waited for 6 months as it is previouslymentioned.

So SCS may allow patients to live withoutpain while waiting for the disease to run itscourse.

We look forward to randomized controlledseries in which the new treatment would becompared in a series of patients some of whom

References

1. Strandness DE, Summer D. Hemodynamics forSurgeons. New York, Grune and Stratton. 1975,pp. 290-291.

2. Myklebust }B, Cusik J, Zyvdoskyi M. Muscle blood

would receive no treatment and where theywould be categorized according to the Committeeon Reporting Standards (I.S.C.S.).̂ "

Based on the reasons given above, we thinkthat SCS has a special place in the fight againstvasospastic and atherosclerotic disease of thelimbs. We believe it is promising in patients withsevere ischemia where other procedures havefailed or cannot be employed.

flow alteration with spinal cord stimulation. Pro-ceed. 14th Meeting of Neuroelectric Society,Athens, June 1985.

3. Augustinsson L. Epidural spinal electrical stimu-

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SPINAL CORD STIMULATION

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Sampere CT, Cuasch |A, Paladino C. et al. La esti-mulacion electrica epidural en la isquemiacronica de los miembros inferiores. AmericanChapter International Society for CardiovascuiarSurgery. Uruguay, Punta del Este, Decembre,1986.Sampere CT, Cuasch JA, Paladino C, et al. La ul-cera isquemica hipertensiva. Un nuevo enfoqueterapeutico. Rev Arg Cir 1986; 51:207-209.Dooley D. Kasprak M. Modification of blood flowto the extremities by electrical stimulation of thenervous system. So Med ] 1976; 60(10):1309-1311.Rivers SP, Veith EJ, Ascer E, et al. Successful con-servative therapy of severe iimb-threatening isch-emia: The value of non-sympathectomy. Surgery1986; 99:759-762.Rutherford RB, Elanigan DP, Gupta SK, et al. Sug-gested standards for reports deaiing with lowerextremity ischemia. Vase Surg 1986; 4:80-94.

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