The management of arterial emboli

The Management

of Arterial

WILLIAM J. MCCANN, M.D., New Rochelle,

From the Vascular Service, Department of Surgery, New York Medical College, Flower and Fifth Avenue Hospitals,

HE TREATMENT of an arterial embolus would appear a prime example of the surgical dictum that mechanical obstruction requires mechanical intervention. Until a reliable agent for in vivo dissolution of blood clots becomes available, surgical removal of the clot will remain the primary mode of treatment. It is not, however, the only mode of treatment; in selected cases nonoperative treatment may be the solution to the over-all management of the patient. As early as 1895, Ssabanejeff [I ] attempted the removal of an aortic embolus, but it was not until 1910 that Labey [Z] demonstrated the feasibility of this direct approach when he performed the first successful embolectomy. T

Diugnosis. The diagnosis of arterial embolus will generally be made in the presence of the typical findings of acute arterial occlusion in the absence of trauma. Pain, usually sudden in onset, is quite characteristic though in some cases it may be more insidious. Coldness, paresthesias and paresis of the affected limb are also present. Examination reveals either the lemon pallor of complete ischemia or the cyanotic mottling seen somewhat later when the associated arterial spasm has diminished. There is diminished sensation and loss of deep tendon reflexes. Arterial pulsations are absent distal to the site of lodgment. Thermal levels are easily distinguished and vary in accordance with the site of the embolus. The localization of the embolus is apparent when the pattern of thermal change and absent arterial pulsations are correlated with the knowledge that emboli become arrested at the sites of bifurcation of blood vessels. Acute arterial thrombosis can usually be differentiated by the lack of a central nidus and a more gradual onset of signs and symptoms. In the series reported by Warren [P] the origin of the emboli was evident in 86.5 per cent of the patients. In the current group a central nidus was chnically apparent in all but two patients (95.6 per cent). It might be generally stated that the patient with pre-existing peripheral arterial disease is more likely to have a thrombosis while the patient with pre-existing

MATERIAL Forty-seven patients having fifty emboli constitute the source of this report. Thirty-two embolectomies were performed on twenty-nine patients; sixteen patients were managed medically and two required no treatment. The site of lodgment of the emboli is listed in Table I. The high incidence of TABLE I LOCATION OFEMBOLI

Number

Per Cent

Aorta.. Iliac. Femoral.

3 8 22 13 4 50

6 16 44 26 8 100

Popliteal . Brachial

Total....

popliteal involvement is in conflict with that generally reported [3]. The heart is the most common Am&can

Journal

of Surgery,

Vol.

108,

Decembev

1964

New York

site of origin of peripheral arterial emboli and in this series accounted for forty-eight of the fifty emboli. The basic cardiovascular disease was thought to be rheumatic valvular disease in twentyone patients, arteriosclerotic valvular disease in fifteen and congestive failure in six. Postmyocardial infarction emboli were seen in four patients in this series. An aneurysm of the abdominal aorta was thought to be the origin of the embolus in one patient. Rhythm irregularities were present in 64.4 per cent of the patients.

New York, New York.

Site

Emboli

768

Arterial cardiac disease is more likely to have an embolus. Pseudoembolic thrombophlebitis, or phlegmasia cerulea dolans, is differentiated by the presence of edema and increased pseudomotor activity. Treatwmat. Despite the recent reports of successful results in delayed cases, speed in the initiation of treatment is still essential and the best results obtain in the patient who is treated promptly. Supportive measures in line with the patient’s general status should be instituted but should not permit a delay in the treatment of the impaired circulation. The immediate administration of an intravenous anticoagulant drug, heparin, is strongly recommended so that extension of a propagating thrombus during the preparation for definitive therapy is inhibited. The involved extremity should be exposed to room temperature. Neither heat nor cold should be applied locally. Papaverine may be used and in the postoperative course is to be preferred to the hexamethonium compounds. No intraarterial medications are administered as it is considered illogical in the presence of impaired circulation. Continuous spinal anesthesia is instituted with the aid of an indwelling catheter, as suggested by Smith [5 1. This precludes the use of repeated paravertebral blocks and the associated risk of hemorrhage in the presence of anticoagulant therapy. A similar technic described by Ansbro [S] is available should the upper extremity be involved. Despite the value of these measures in selected cases in whom the operative risk is prohibitive, surgical management is the undisputed treatment of choice and when performed early the results are good. Spinal anesthesia has been used for emboli of the trunk and lower extremities whenever the anesthetist did not have a serious objection to its use. In the poorer risk patient local anesthesia for emboli of the femoral, brachial and popliteal arteries is quite satisfactory. Transabdominal transperitoneal approach to the aortic and iliac arteries is preferred. The other vessels are approached by a longitudinal incision placed directly over the course of the vessel with the exception of the popliteal which is approached through an S-shaped incision. At times, during exploration of the femoral artery, an extension of the exposure to include the iliac vessels is desirable. In this instance a second incision is made over the lower part of the abdomen and the external oblique muscle is then detached from the ilium and the retroperitoneal

Emboli space entered. The inguinal ligament is not divided. The peritoneum and its contents are rolled upward and medially, and the entire iliac and lower aortic systems are thus exposed. When the involved vessel is exposed, proximal and distal control is obtained and the vessel opened in longitudinal fashion just distal to the site of the embolus through an uninvolved portion of the wall. The site of the embolic involvement is indicated by ecchymotic discoloration of the wall of the artery. The vis u tevgo will usually expel the clot. If not, gentle digital milking is generally sufficient to express any remaining clot. After this the proximal vessel is flushed out with a bulb syringe containing a heparin-saline solution. Effective pulsatile arterial flow into the syringe may be easily and safely demonstrated in this fashion. The proximal artery is again clamped and attention directed toward the distal end. If good back Aow is present, heparin solution is injected and the arteriotomy closed with continuous over and over fine arterial silk sutures. If back flow is absent, a second distal arteriotomy with retrograde flush, as described by Lund [7] and later advocated by Olwin, Dye and Julian [8], should be employed. In this regard, the surgeon should make every effort to clear out the distal arterial tree and multiple arteriotomies including the posterior tibia1 and dorsalis pedis vessels utilized when necessary. After the removal of an extending thrombus the proximal arteriotomy site is closed and circulation re-established so as to demonstrate pulsatile bleeding through the distal arteriotomy incision which is then closed without again interrupting the circulation. In those cases in which retrograde flush was utilized, immediate postoperative anticoagulant therapy is begun. Results. The results obtained following treatment as outlined are listed in Table II. Eighteen patients with peripheral emboli were managed without surgical intervention. The lower femoral, popliteal and brachial arteries were involved in these cases. In all cases it appeared evident at the time the patient was first seen, that collateral circulation was adequate to insure viability. Loss of functional capacity was accepted in this poor risk group as a compromise to avoid operative mortality. In two patients, however, delayed amputation for severe ischemic symptoms was required. In the remaining sixteen patients there have been variable lesser degrees of ischemic manifesta-

McCann TABLEII RESULTOFTREATMENT

Operative Early

h’onoperative

Delayed

Gangrene

Deaths

_ Aorta. Iliac. . Femoral Popliteal Brachial. Total

3 5 10

.. .

3 6 3

.. .. 2: (40%)

12 (24.0%)

-

-

tions and diminished functional capacity. This experience has suggested that surgical intervention should be more widely employed in emboli involving these vessels so that retained physical capacity and not mere viability is achieved. Thirty-two operations were performed on the remaining twenty-nine patients. Twenty operations were performed less than twentyfour hours after the onset of symptoms. The remaining twelve operations were performed between twenty-four hours and five days after symptoms began. In the group in whom early operation was carried out, circulation was restored in 85.0 per cent of the cases. There has been a recent emphasis on extension of the time interval after which surgery might be undertaken in this disease. Delayed embolectomy in our hands has not been very successful. Five of the eight patients in whom gangrene occurred were in the delayed operation group. The retrograde flush technic was utilized in all five patients. Circulation was restored in only seven (58.3 per cent) of the twelve cases in the delayed group, in contrast to 85.0 per cent of the early operative group. There were eight deaths in this series, or a mortality rate of 14.3 per cent. The mortality rate among the operated patients was 27.6 per cent. There was no mortality among the group in whom no operation was performed. (Table III.)

6 10 2

2” 3

18 (36.0%)

: (16%)

2 4 2 0 0 8 (14.3%)

The causes of death are listed in Table W. The first patient, a thirty-six year old woman, was admitted to the hospital with a transient episode of aphasia and hemiparesis. There followed two distinct iliac emboli with consecutive successful embolectomies performed thirty-six hours apart, only to be followed by a third fatal cerebral embolus less than twentyfour hours after the second embolectomy. Fatal cerebral embolization occurred in two additional patients. Death occurred in a fifty-six year old woman from a massive pulmonary embolus eight days following a mid-thigh amputation. In a second patient, an eighty-three year old woman who had had an aortic embolectomy performed for a saddle embolus and developed gangrene of the right foot postoperatively, a leg amputation was performed one week following the embolectomy and death occurred suddenly on the third postoperative day. A pulmonary embolus was considered to be the cause of death but an autopsy was not obtained. Thus in one patient, and possibly in a second patient, death was related to venous stasis thrombosis. This suggests that concomitant vein ligation at the time of amputation is logical. Anticoagulants are used freely preoperatively, at operation and postoperatively. The

TABLE TABLE III MORTALITYDATA

IV

CAUSES OFDEATH Cerebralembolus

Operative Nonoperative Over-all

32 18 48

8 0 8

Pulmonary embolus (postamputation) Probable pulmonary embolus (postamputation) Nonhemorrhagic irreversible shock Cardiac failure Coronary occlusion Total

25.0 0.0 14.3

770

3 1 1 1 1 1 8

Arterial Emboli the light of retained functional capacity and a symptom-free extremity. 3. Aggressive treatment promptly instituted offers the best chance of a favorable outcome in this disease. In this series the over-all mortality rate was 16.3 per cent and the incidence of gangrene was 16.3 per cent. Since death occurred in three of the patients who developed gangrene, the patient failure rate was 27.0 per cent. 4. Restoration of circulation was attained twice as frequently when operation was performed in the first twenty-four hours after the onset of symptoms.

use of these drugs is considered a necessity in delayed cases and when retrograde flush technic has been employed. There have been no serious untoward results with the use of these drugs concomitant with surgery. Subcutaneous ecchymosis and wound hematoma have been noted. At present, the use of thrombolytic substances in the management of arterial emboli is contraindicated as a primary therapeutic agent. When used in conjunction with embolectomy with the thought of dissolving secondary stasis thrombi, there is some logic and perhaps merit to their use. This view is supported by the observation that “clot resistance” renders the lytic agent ineffective after approximately seventy-two hours. Accordingly, the majority of arterial emboli are “over aged” at the very moment that they have become a clinical entity in the peripheral circulation. Without a satisfactory method to preselect those emboli which might be dissolved, valuable hours would be irretrievably lost in the many cases in which the blood clot was resistant to the thrombolytic substances.

REFERENCES 1.

J. Quoted by G. Murray. Canad. JI. J., 35: 61, 1936. 2. LABEY, G. Quoted by E. Key. Surg. Gynec. & Obst., 36: 309,1923. 3. MCCANN, W. J. Arterial embolism. New York J. SSABAKEJEFF,

Med., 59: 2559,1959. 4. WARREN, R., LINTON, R. and SCANNELL, J. G. Arterial embolism. Ann. Surg., 140: 311, 1954. 5. SMITH, S. M. and REES, V. L. Use of prolonged continuous spinal anesthesis to relieve vasospasm and pain in peripheral embolism. Anesthesiology, 9: 229,1948. 6. ANSBRO, F. P. A method of continuous brachial block. Am. J. Surg. 71: 716, 1946. 7. LUND, C. C. Treatment of embolism of the greater arteries. Ann. Surg., 106: 880, 1937. 8. OLWIN, J. H., DYE, W. S. and JULIAS, 0. Late peripheral arterial embolectomy. Arch. Surg., 66: 480,1953.

SUMMARY

1. A series of forty-seven patients having fifty emboli is presented. 2. Operative management is stressed as the primary mode of treatment when considered in

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