REID E T AL.: PHENOL INJECTION OF T H E SYMPATHETIC CHAIN 45

PHENOL INJECTION OF THE SYMPATHETIC CHAIN BY WILLIAM REID, J. KENNEDY WATT, AND THOMAS G . GRAY

GLASGOW ROYAL INFIRMARY AND THE PERIPHERAL VASCULAR UNIT, BELVIDERE HOSPITAL

SUMMARY An account is given of the technique of phenol

sympathetic block and its value in the treatment of ischaemic rest pain, gangrene, intermittent claudica- tion, Paget’s disease of bone, tip necrosis of fingers, hyperhidrosis, poliomyelitis with chilblains and severe ulceration, and pain associated with chronic pancreatitis and carcinoma of pancreas.

The only complication which occurs with any frequency is the development of neuritic pain which is usually self-limiting. Other complications are infrequent and the safety of the method in experi- enced hands is undoubted.

majority persistent pain leads to a decision to ampu- tate or the patient may demand amputation.

In this type of case, phenol injection of the sympa- thetic chain has its greatest value and has been found to abolish rest pain in many cases.

During 1952-60, 189 male patients presented with ischaemic rest pain associated with trophic changes, cyanosis, oedema, ulceration, or minimal tissue

IN peripheral vascular disease, successful reconstruc- tive surgery can restore normal blood-flow to the limb. Unfortunately the arterial lesion is not amen- able to surgery in the majority of cases and other methods of treatment have to be considered. In our hands phenol injection of the sympathetic chain has proved to be of great value in relieving ischaemic rest pain, in averting or limiting tissue necrosis, and in the partial or complete relief of other disabling symptoms.

This paper discusses our experience and the results obtained in more than 5000 injections. The number of patients treated by this method is increasing annually, and 1042 injections were performed in Belvidere Hospital alone during 1967 and 1968.

Following Mandl’s experiments in 1946 on the effects of phenol on the sympathetic chain of cats (Mandl, 1947), Haxton (1949) published the results of injection of the lumbar sympathetic chain with 10 per cent phenol in cases of occlusive arterial disease. Also in 1949, Boyd, Ratcliffe, Jepson, and James discussed the use of 10 per cent phenol in the treatment of this type of patient and considered it to be of value.

Independently, one of us (W. R.), being also stimulated by Mandl’s work, began to use phenol injection in 1950. Initially a solution of phenol in oil was used, but this was ineffective because phenol is inactivated by oil. As phenol is soluble in water in a dilution of I : 13, a solution of I : 15 (6.7 per cent) in water was prepared and this concentration has been used to the present time.

INDICATIONS FOR PHENOL INJECTION I. Ischaemic Rest Pain.-When ischaemia is

severe and viability of the limb is threatened, rest pain interferes with or prevents sleep. Relief may be obtained by dependency, but continued dependency produces oedema and stasis which may precipitate tissue necrosis and establish gangrene. Spon- taneous improvement in the collateral circulation gives relief of rest pain in a few cases, but in the 4

FIG. this elderly patient presented with ischaemic rest pain and minimal tissue necrosis of the left second toe. His pain was relieved by phenol injection and the toe gradually healed. Two years later he presented with an identical lesion in the right second toe and this responded to phenol injection and healed with minimal loss of tissue.

necrosis (Fig. I). Phenol injection was carried out in all cases and 145 (76.7 per cent) were relieved of rest pain. Ganglionectomy was performed in 3 patients with relief of pain, and the remaining 41 (21.7 per cent) showed no improvement and required amputation.

One hundred and thirty of the 148 patients who obtained relief of rest pain were followed up in 1962 and 56 were found to have died (coronary throm- bosis, 34; cerebral vascular disease, 9; other causes, 13). The mean survival time was 2.2 years, and 6 had developed gangrene of the same leg and 3 of the opposite leg.

Of the 74 patients still alive, 8 developed recur- rence of symptoms in the same leg within z years and required amputation and the remaining 66 had remained free from further incidents in the treated leg (mean duration of freedom 4‘25 years). However, 9 developed ischaemic rest pain in the opposite leg and were relieved by phenol injection to the lumbar

46 BRIT. J. SURG., 1970, Vol. 57, No. I, JANUARY

sympathetic chain and I developed gangrene of the opposite leg and required amputation.

In summary, of the original 189, 41 required early amputation, 14 derived some benefit from phenol injection but had a further occlusive incident and developed gangrene of the same leg, 4 subsequently developed gangrene of the opposite leg, and 18 were not traced. One hundred and twelve (59-3 per cent) were known to have been relieved of rest pain from the time of phenol injection until they died or were seen at follow-up.

3. Intermittent C1audication.-Assessment of the value of treatment of this symptom is difficult, but we have no doubt that many patients with inter- mittent claudication do benefit from phenol injection.

In 1961 (Reid, Watt, and Gray, 1961) a survey of 223 claudicating patients treated by phenol injection showed that 30-40 per cent of superficial femoral and femoropopliteal occlusions responded well but only 11 per cent of aorto-iliac occlusions did so. Sub- sequent observation has confirmed these findings and has shown that treatment of unilateral common iliac, superficial femoral, short adductor, and short popli- teal occlusions gives very good results whereas in other aorto-iliac lesions, extensive femoropopliteal, tibial, and multiple occlusions the response is un- certain and often marginal.

A retrospective analysis of 264 patients with inter- mittent claudication owing to femoropopliteal

FIG. 2.-This non-diabetic patient presented with severe rest pain and necrosis of the toes of the right foot. Phenol injection of the lumbar sympathetic chain relieved his rest pain and the necrotic toes separated leaving a healthy foot.

2. Established Gangrene.-When gangrene is confined to the toes and does not extend on to the dorsum of the foot, phenol injection frequently relieves pain and allows demarcation and separation of the necrotic tissue (Fig. 2) .

When major amputation is inevitable owing to exten- sive tissue necrosis, phenol injection has permitted successful below-knee amputation in approximately 50 per cent of our cases.

In 1960-5, 121 non-diabetic patients required amputation for arteriosclerotic gangrene. Nineteen male patients had bilateral amputation, so that 140 primary lower limb amputations were performed. There were 16 postoperative deaths. In the 105 survivors of amputation, 79 below-knee and 42 above- knee amputations were originally performed. Of these, 62 below-knee stumps (78.5 per cent) healed (4 after revision of the stump) and 37 above-knee stumps (88 per cent) healed (3 after revision of the stump). Below-knee amputation failed in 17 cases and these were converted to above-knee amputation. The final level of amputation was 62 below-knee amputations and 59 above-knee amputations.

The introduction of the new lightweight lower- limb prosthesis has been of great value to these amputees. The elderly man or woman with a single below-knee prosthesis enjoys a freedom of movement denied to the patients with a mid-thigh amputation and, for this reason, the achievement of a satisfactory below-knee stump is a valuable gain.

occlusions treated by phenol injection was undertaken to determine which cases might reasonably have been treated by arterial surgery. Patients under 60 years of age with no gross cardiac lesion, in whom there was a unilateral adductor occlusion of 10 cm. or less, with patent tibial vessels and no lesion in the opposite leg, were considered ideally suitable for surgery. There were 24 such cases (9 per cent). Following phenol injection, 6 of these had no claudication; 10 were able to walk I mile or more without stopping; and in 4 cases the claudication distance was + mile, 300 yd., zoo yd., and 50 yd. respectively. Four cases were not traced. Four members of this group had a subsequent occlusive vascular incident in the other leg.

One of the best indications of the value of phenol in intermittent claudication is seen in patients with bilateral occlusion. These patients often complain of unilateral claudication which develops in the more severely ischaemic limb before the exercise tolerance of the other leg is reached. After phenol injection, reversal of symptoms is quite common and the patient complains of claudication in the previously symptomless leg. Phenol injection of the second side will then give a second reversal of symptoms restoring the original symptom pattern, and with this sequence the patient experiences a gratifying improvement in his overall walking distance.

4. Osteitis Deformans (Paget’s Disease of Bone).-Paget’s disease of bone can cause severe

REID E T AL.: PHENOL INJECTION O F T H E SYMPATHETIC CHAIN 47

pain which is difficult to relieve. Phenol injection of the sympathetic chain at appropriate levels in 14 patients has been shown to relieve pain for periods of 6-8 years (Reid, 1960). Treatment was consistently successful when the limbs were affected but was not effective in patients with disease of the spine or pelvis.

5. Tip Necrosis of Fingers.-In the treatment of Raynaud’s disease, surgical sympathectomy gives disappointing long-term results. For this reason, phenol injection of the sympathetic chain is not used

TECHNIQUE The injection of local anaesthetic solution in the

paravertebral region is safe and the addition of hyaluronidase, which aids diffusion, will produce a maximum effect on the sympathetic chain even if the needle is not accurately sited. The injection of phenol solution, on the other hand, is potentially dangerous and the avoidance of complications depends on the accurate siting of the needle.

The technique of paravertebral injection described in standard textbooks is not suitable for the injection

FIG. 3.-This 21-year-old fenale patient presented with Raynaud‘s disease which had caused trophic changes in the pulp of the fingers and a small but very painful ischaemic ulcer in the middle finger. Phenol injection of the dorsal sympathetic chain at D.2 relieved her rest pain and the finger healed.

unless severe trophic changes are present. Where tip necrosis and rest pain have developed, phenol injection at D.2 or D.3 can give relief of pain and permit healing of the affected finger (Fig. 3). This has been used in 27 patients.

Because of the relatively high incidence of pneumo- thorax with phenol injection at this level surgical sympathectomy may be preferable in fit patients.

6. Hyperhidrosis.-This is a rare condition caused by sympathetic hyperactivity and severe hyperhidrosis can interfere with work and be a grave social embarrassment. Phenol injection of the sympathetic chain is as effective as surgical sympa- thectomy in abolishing the excessive perspiration and has been used successfully in 3 patients.

7. Poliomyelitis.-Patients who have a weak or paralysed cold leg as a result of poliomyelitis may develop painful chilblains with superficial necrosis. Phenol injection has given relief of pain and healing of the skin lesions in 16 such cases, and the resultant improvement in the colour of the cyanosed limb suggests that treatment produces a more active flow rather than a loss of vasoconstrictor tone.

Bilateral injection has been avoided in young boys because of the possibility of producing sterility and only one injection of 2 ml. phenol at L.4 is normally given.

8. Pancreatitis.-The severe pain, vomiting, and shock of acute pancreatitis can be relieved by the paravertebral injection of lignocaine and the patient’s general condition thereafter improves.

Because of the efficacy of local anaesthetic solution, phenol is unnecessary in acute pancreatitis, but phenol injection at D.8 and D.9 has been used successfully to relieve the pain associated with chronic pancreatitis and pancreatic carcinoma in 7 cases.

00

FIG. 4.-Diagram to show the relationship of the lumbar sympathetic chain to the vertebral body and psoas fascia. The injecting needle must be entered laterally 10-12 cm. from the midline to reach the sympathetic chain.

of phenol around the sympathetic chain. Labat’s (1922) description of paravertebral block in which he recommends that the needle be entered 3 cm. from the midline is widely quoted, but reference to Labat’s original work reveals that he was describing paravertebral block of the lumbar plexus, not the sympathetic chain. When skin puncture is made too near the midline, the needle cannot negotiate the curve of the vertebral body and reach the sympathetic chain which lies in front of the body. A lateral punc- ture 10-12 cm. from the midline (in the lumbar region) outflanks the transverse processes and allows accurate siting of the needle (Fig. 4).

A premedication of 50 mg. pethidine or 4 gr. Omnopon (papaveretum) is given 20 min. before the phenol injection* is undertaken. For nervous patients

The phenol is dissolved in the required quantity of sterile distilled water. This solution is filtered through a No. 3 porosity sintered glass filter into a Clinbritic bottle and sterilized by heating at 100’ C. for 45 minutes.

48

this is supplemented by 25 mg. of Sparine (proma- zine hydrochloride).

Chain.-The patient lies in the lateral position with the side for injection uppermost, the head being supported on one pillow ( F ~ . 5 ) . A ro-ml. syringe

BRIT. J. SURG., 1970, Vol. 57, No. I , JANUARY

The stylet is partly withdrawn and a drop of phenol solution is placed on the butt of the needle before

I. Injection of the Lumbar Sympathetic complete withdrawal of the stylet. If the drop is sucked in, the needle may have entered the pleural cavity. If the drop is extruded, this is due to punc- ture of the aorta, vena cava, a lumbar vessel, or, in rare instances, a prolongation of the subarachnoid space. Injection is delayed for 20 seconds to exclude

FIG. 5.-Photograph of patient with needle in situ. The iliac crest, 12th rib, and lumbar spinous processes are marked.

FIG. 6.-The 10-cm., 13-cm., and 15-cm. needles used for phenol injection.

is filled with I per cent lignocaine and skin weals are made at two sites 10-12 cm. from the midline opposite the bases of the 3rd and 4th lumbar spinous processes. A few millilitres of solution are infiltrated to a depth of 4-5 cm. and the skin is punctured with a needle of wider bore than that used for phenol idjection, so that skin-resistance to the latter needle is minimal.

A 13-cm. Howard Jones needle with a short bevel and stylet (Fig. 6) is entered and directed medially to reach the side of the vertebral body whose charac- teristic bone resistance is easily recognized. The needle is then withdrawn several centimetres and directed more laterally to clear the anterolateral aspect of the vertebral body (Fig. 4). An elastic resistance at this stage is due to penetration of the anterior longitudinal ligament and indicates that the needle is too close to bone. Approximately I cm. beyond the crest of the body the slight resistance of psoas fascia is encountered and penetration of this layer brings the needle point into close relation to the sympathetic chain. In heavily built patients a 15-cm. needle may be required (Fig. 6).

FIG. 7.-This radiograph shows the spread of 3 ml. 76 per cent urografin injected by the technique used for phenol block. This was performed subsequent to aortography and the left ureter is outlined by the excreted dye.

the latter. Occasionally, penetration of the renal pelvis or ureter will yield urine.

If the drop of solution remains stationary, the syringe containing phenol is attached and aspiration performed. If there is no yield, 0.5-1 ml. of I : 15 phenol solution is injected. This should meet no resistance, the pressure required being equivalent to that in intravenous injection. Aspiration and injection are continued until 3 ml. have been injected, and the procedure is repeated at the second site.

Although the phenol solution does not diffuse, it tends to spread if injected in the correct layer (Fig. 7 ) , and a successful injection opposite L.3 and L.4 pro- duces results equivalent to that of surgical sympa- thectomy.

Preliminary Novocaine (procaine) injection of the sympathetic chain is never used since this may dilute or partially inactivate the phenol solution.

2. Injection of the Upper Dorsal Sympathetic Chain.-The lateral position is used as described above with the head slightly flexed and the shoulder

REID E T AL.: PHENOL INJECTION O F THE SYMPATHETIC CHAIN 49

allowed to fall forwards to pull the scapula outwards. Following infiltration with local anaesthetic, injection is made through a point 7 cm. from the midline opposite the tip of the spinous process of the second dorsal vertebra, the needle passing above the second rib. The needle used is 10 cm. long (Fig. 6) and, as the possibility of pleural puncture is high, it is kept close to the vertebral body at all times. The correct depth is less than I cm. beyond the crest of the vertebral body where a definite loss of resistance is felt. It is essential to place a drop of solution on the butt of the needle and, if it is rapidly sucked in, the needle must be withdrawn immediately. If the drop remains static for 20 seconds, 2 ml. of I : 15 phenol solution are injected carefully after aspiration as described above.

Injection at this level (D.2) produces a warm, dry, sympathectomized hand without, as a rule, causing a Horner’s syndrome. If an effect in the face or neck is desired, injection is made opposite D.1, but a Horner’s syndrome is produced by injection at this level.

Effect of Phenol Injection.-With successful injection, the hand or foot becomes warm and dry as after surgical sympathectomy and the effect may be maintained for years. The temperature increase is equivalent to or better than that obtained by the reflex vasodilatation test of Gibbon and Landis (1932), and the rate at which the effect develops depends on the state of the myocardium and the efficiency of the collateral circulation. In a healthy patient with a short arterial occlusion and excellent collaterals the foot may be warm at the conclusion of injection but, where the collaterals are poor, the response may be delayed for several hours. A temporary drop in blood-pressure of less than 20 mm. Hg can occur but this does not usually produce symptoms.

In some cases the improvement in circulation is such that a previously absent posterior tibia1 pulse can be palpated on the day following phenol injection.

Successful injections are not routine. The initial success rate may be less than 50 per cent but, as experience is gained, the proportion of successful injections should be about 75 per cent and the incidence of complications will diminish.

Bilateral phenol injections are not undertaken at one session. The normal practice is to inject one side and allow a month’s interval for the collateral circula- tion to become established before the other side is injected. In an elderly patient with a poor myo- cardium and severe ischaemia of both legs, phenol injection of the lumbar sympathetic chain will give a relative advantage to the circulation of the leg on that side. This advantage may be lost if the lumbar sympathetic chain on the other side is subsequently injected.

Mode of Action of Phenol Injection.-Although the subsequent vasodilatation and anhidrosis of the limb is evidence of interruption of the sympathetic outflow, the exact mode of action of phenol on the sympathetic chain is not known.

In experiments on rabbits the sympathetic chain was surgically exposed and bathed in I : 15 phenol, and subsequent histology showed that the ganglion cells remained intact. There have been occasional opportunities to study this in man when surgical sympathectomy was performed following phenol

injection. In these cases the paravertebral tissues were densely fibrosed and ganglia were present, but the ganglionic chain was attenuated. The action of phenol would therefore appear to be due to inter- ference with conduction through the sympathetic nerve-fibres.

It also appears probable that afferent pain-fibres are interrupted as phenol injection at appropriate levels is very effective in relieving the pain of Paget’s disease of bone (Reid, 1960) and of chronic pancrea- titis. This suggests that some factor additional to the vasodilatation effect contributes to the success of the procedure.

Advantages of Phenol Injection of the Sympa- thetic Chain.-An adequate ‘ sympathectomy ’ effect with relief or amelioration of symptoms is obtained by a short simple method which obviates the risks of operation. Full activity is resumed within an hour of injection, thus avoiding the tendency to throm- bosis which is associated with bed-rest after operation under general anaesthesia. The patient can return to work on the following day, a distinct economic advantage, and a large turnover of patients is possible with economy in bed space.

COMPLICATIONS These are few and transient when the technique

is carefully applied using I : 15 phenol in water.

Table I.-~OMPLICATIONS OF PHENOL INJECTION OF

INJECTIONS) LUMBAR SYMPATHETIC CHAIN I N 1028 PATIENTS (1666

No. of Cases

Death I Paraplegia 0 Hypotensive collapse I Renal or ureteric involvement 5 Intrapleural injection 6 Neuritis of groin or thigh 1 so

Complicarions

I. Death.-One death has occurred during the past 10 years due to paravertebral injection of phenol solution. At the conclusion of an apparently success- ful lumbar injection cardiac arrest occurred and the patient could not be resuscitated. Post-mortem examination showed no cause for death, a coinci- dental finding being pyonephrosis of one kidney.

Another case of cardiac arrest occurred after an injection of 2 ml. phenol at the level of D.3 in a patient with angina at rest. This responded to external cardiac massage and the patient survived the incident.

I t is surprising that deaths have not been more frequent as many of these patients are poor surgical risks and some have died from coronary thrombosis or cerebral vascular incidents prior to admission, or, in some cases, after admission but before phenol injection.

2. Neuritis.-In a follow-up of 1028 patients who were given 1666 injections of phenol solution to the lumbar sympathetic chain (some bilateral), the only common complication, occurring in 9 per cent of injections (14.6 per cent of patients), was burning numbness in the groin or the adductor region of the thigh (Table I ) . Occasionally, the outer side of the thigh was affected. In the upper dorsal region a similar type of pain affects the chest wall and the inner aspect of the upper arm.

5 0 BRIT. J. SURG., 1970, Vol. 57, No. I, JANUARY

The pain is intensified by contact with clothing but is seldom severe and rarely persists for more than 6-8 weeks although numbness may remain. The pain usually responds to simple analgesics, e.g., aspirin or codeine, and the patient can be reassured that it is neither serious nor permanent and is due to overspill of the solution to sensory pathways.

3. Pulmonary.-Pneumothorax is a frequent complication when injection is performed in the upper dorsal region and is a rare complication of high lumbar injection. It appears to be due to puncture of the lung rather than aspiration of air as it may not become evident until an hour after the injection. Full re- expansion has been obtained in all cases, although I patient required insertion of a catheter with a water- seal drain. Haemoptysis has occurred on a few occasions without untoward sequelae.

4. Renal.-Puncture of the kidney sometimes occurs and is recognized by a pendulum swing of the needle or by the escape of urine through the needle. The presence of peri-ureteric fibrosis at subsequent ganglionectomy has occasionally been seen and it is possible that urinary symptoms may occur owing to ureteric damage.

Injury of kidney or ureter may produce haema- turia, renal colic, or dysuria, but in most cases the symptoms are transient and full recovery results.

5. Intravascular Injection.-Although penetra- tion of the aorta, inferior vena cava, or lumbar veins can occur, intravascular injection is rare. To avoid this complication, it is essential to aspirate gently before the injection of each 0.5 ml. of phenol solution, as the position of the point of the needle can change with respiratory movement and penetration of a vein may not be detected unless repeated aspiration is performed.

Intravascular injection causes severe tinnitus and flushing within a few seconds but recovery is rapid and complete.

6. Hypotensive Collapse.-Hypotensive collapse might be expected when the collateral circulation in the leg of an elderly patient dilates after injection. Fortunately, such collapse is uncommon (Table I ) and it responds to elevating the foot of the bed.

Premedication with pethidine has been a more frequent cause of hypotension than phenol injec- tion. 7. Horner’s Syndrome.-Horner’s syndrome of

miosis and enophthalmos follows injection at the level of D.I and may occur with injection at D.2 if too much phenol solution is injected. This complication has been rare since the volume of phenol solution injected at D.2 was limited to 2 ml.

8. Sterility.-Bilateral injection in the lumbar region in men causes loss of ejaculation, although

impotence does not occur and the patient is not necessarily sterile. This is rarely a cause for concern in older patients, but in young patients the improve- ment likely to be obtained by phenol injection must be carefully balanced against the possibility of producing sterility.

Bilateral injection in women does not appear to affect fertility or prevent conception.

9. Paraplegia.-Paraplegia has not occurred in this series although cerebrospinal fluid has been tapped on three or four occasions. If the needle has been accurately sited and an interval of 20 seconds is allowed before injection of phenol solution, it is unlikely to occur.

DISCUSSION Sympathetic block with phenol is a controversial

method of treatment which is potentially dangerous. With an appreciation of its dangers and mastery of the technique, phenol block is safe and efficacious in a variety of conditions in which other measures are less successful.

The effect produced appears to be equivalent to that of surgical sympathectomy, there being an increased blood-flow to the limb owing to dilatation of the smaller vessels and sweating is abolished. The relief of pain in Paget’s disease and chronic pancrea- titis, however, suggests that it may have an additional action by interruption of afferent pain pathways mediated through the sympathetic nervous system, although there is no available evidence to confirm this view.

Phenol block is not superior to direct arterial surgery when this is possible, but it is invaluable in the treatment of the numerous cases where surgery is contra-indicated or not technically feasible.

Acknowledgements.-We wish to express our sincere thanks to Sir Ian Fraser for his helpful criticism and to Mrs. M. Baird for her valued secretariaf services and her efficiency in tracing so many patients.

REFERENCES BOYD, A. M., RATCLIFFE, A. H., JEPSON, R. I?., and JAMES,

G. W. H. (rg@),J. BoneJt Surg., 31B, 325. GIBBON, J. H., and LANDIS, E. M. (1932),J. clzn. Invest.,

I I , 1019. HAXTON, H. A. (1949)~ Br. med.J., I , 1026. LABAT, G. (1922), Regional Anesthesia, p. 240. Philadel-

phia and London: Saunders. MANDL, F. (1947), Paravertebral Block in Diagnosis, Prog-

nosis and Therapy: Minor Sympathetic Surgery (trans. KALLNER, G.). New York: Grune & Stratton.

REID, W. (1960)~ Scot. med. J., 5, 71. -- WATT, J. K., and GRAY, T. (1961), Zbid., 6, 228.