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The Therapeutic Use of Procaine Hydrochloride Injection
The Therapeutic Use of Procaine Hydrochloride Injection GEORGE P. WHITELAW, M.D.*
THIS subject is one of interest to the general practitioner, internist and surgeon alike. Each one frequently encounters problems that might be successfully treated by the utilization of procaine injection. In certain instances, temporary alleviation of symptoms by such methods may point toward more definitive surgical measures, and, in this way, the therapeutic use of procaine is inevitably closely linked with its diagnostic use. However, we will limit this discussion to therapy insofar as possible. Traditionally, surgeons and anesthetists have performed these maneuverso The more complicated procedures should obviously be limited to experienced hands. Nevertheless, there is no reason why internists and general practitioners should not become skilled in their use. For the most part, these injections can be carried out in the office. While primarily general surgeons, Dr. R. H. Smithwick and the surgical group associated with him in the Medical Associates of the Massachusetts Memorial Hospitals have been interested in vascular and sympathetic nervous system surgery. For this reason, a rather wide experience with problems relating to the sympathetic nervous system has accumulated during the past 20 years. A segment of this material will be used as a basis for our discussion of the therapeutic use of procaine injection. During the past three years, we have performed approximately 400 injections of various kinds, both in the office and in the hospital, and approximately 75 per cent have been in relation to the stellate or lumbar sympathetic ganglia. Though procaine blocks are applied more generally to portions of the sympathetic nervous system, other indications for blocking maneuvers have arisen, as will be apparent in the discussion which follows. From the Department of Surgery, Massachusetts Memorial Hospitals and The Boston University School of Medicine, Boston.
* Visiting Surgeon, Massachusetts Memorial Hospitals; Associate Professor of Surgery, Boston University School of Medicine. 1503
George P. Whitelaw
1504 PAIN
While injection therapy has been performed in a few instances for such conditions as cerebral thrombosis, Meniere's disease and Bell's palsy, the symptom of pain is the most common indication for treatment by injection of local anesthetic agents. By definition, painful states are purely a sUbjective phenomenon. To gain objective data during an attack or after its relief is extremely difficult. Although we can utilize skin resistance studies, skin temperatures, plethysmography, electrocardiograms and step tests for preoperative and postoperative treatment evaluation, nevertheless, for the most part one can gain only an estimate of the severity of symptoms before treatment and the effect of any procedure from what the patient himself says. In this type of study, it is recognized that a large margin for error is present in such evaluation and that psychogenic factors may play a role. Analysis of therapeutic results by the statistical method would be almost meaningless in most of these painful conditions. Hence, the evaluation of certain procedures in alleviation of symptoms can best be gained from the composite experience and resultant impressions of a number of individuals. The following discussion will deal with our opinion regard1ng indications, technique and results of those procedures with which we have had experience. Statistical analyses will not be attempted. The efficacy of blocking procedures in certain of the conditions to be discussed are as yet extremely doubtful, some are in the stage of evaluation, while in other conditions the value of this procedure is cleal'-cut and generally accepted. Nerve blocking therapy has been advocated in some conditions for which the indications and rationale are somewhat difficult to discern. An example of this is the use of stellate blocks in Raynaud's disease or hyperhidrosis. Unless the patient's conviction of the efficacy of upper dorsal sympathectomy requires the demonstration of a block during a period of vasospasm, or marked perspiration, one might better proceed with the sympathectomy when clearly indicated. However, this is a relatively new field and procedures which may seem irrational from a physiological standpoint at this time may be found to have a sound basis for their use as our knowledge of etiological mechanisms in some of the disorders broadens. As Bonica1 has mentioned, "It is important to realize that the nerveblock method of managing intractable pain is not completely innocuous and unless one is ready to admit that analgesic blocking has certain limitations, is replete with certain disadvantages, and is not infrequently attended by failure, the results will be disappointing to both patient and physician." SAFEGUARDS IN THE USE OF BLOts:KING AGENTS
Although, in our own experience, we have been fortunate in not encountering a major catastrophe foYowing any blocking procedure, we
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have this possibility constantly in mind and take every precaution to avoid adverse reactions. Potential dangers exist with injection therapy because of the introduction of the needle itself and because of the reaction to the drug used. Even in the most experienced hands, certain reactions may occur to blocking procedures with any drug. The more alarming of these are (1) blood vessel injection, (2) pneumothorax and (3) subarachnoid injection. We have had one partial pneumothorax due to introduction of the needle into the pleura during a stellate block, and three cases of unilateral recurrent laryngeal nerve paralysis. Several reactions have occurred to the procaine itself. Adriani, Parmley and Ochsner2 state that reactions to procaine may be of two varieties, depressive and convulsive, and that barbiturates are helpful in avoiding the convulsive type of reaction. We have had no instances of the convulsive type but have had several depressive reactions with dizziness, lowering of blood pressure and rapid pulse. While Adriani et al. do not feel that barbiturates are helpful in avoiding the depressive reaction, we routinely use 120 mg. (2 grains) of Luminal Sodium subcutaneously prior to any injection in which more than 5 cc. of procaine is to be used. Since this routine has been adopted, the reaction to procaine has practically disappeared. Because of the potential danger of subarachnoid injection, Rovenstine3 advocates that a kit containing the usual resuscitative agents be close at hand when any block is performed. We agree with this advice. Though not completely infallible in avoiding such a calamity, frequent aspirations should be made to determine whether or not the needle tip is in the subarachnoid space when near the intervertebral foramen. This routine should always be observed to avoid the introduction of procaine into a blood vessel as well. As Adriani et a1. 2 have mentioned, an excellent way to determine whether the needle point has been introduced into the pleura is to place a drop or two of the blocking agent into the hub of the needle when disconnecting the syringe. If the patient takes a deep breath, the fluid will either rapidly disappear or be rapidly expelled. This is not infallible either but should be observed when introducing needles near the pleura. STELLATE GANGLION BLOCK
Because of its anatomical relationship to the sympathetic nerve supply of the head, neck and upper extremities, the stellate ganglion is the most important structure to be considered in the over-all use of blocking procedures. Further emphasis has been placed on the importance of this structure since a book, encompassing it as the sole subject, has been published by Moore. 4 As in all portions of the sympathetic nervous system, anatomical variation can occur. Martinez 5 made a special study of the stellate ganglion in this respect and found it may migrate slightly superiorly or
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inferiorly. Having observed the anatomical position of this ganglion on somewhat over 300 different occasions, it is our impression this structure is one of the least variable of all the ganglia. It lies directly anterior to the inner aspect of the first rib near its articulation with the transverse process of the first thoracic vertebra. It is a large structure and may reach a length of 2 cm. The stellate ganglion is a result of fusion of the inferior cervical and first thoracic ganglia and is one single structure of varying shapes. It may be dumbbell in form, cone-shaped or actually stellate. As stated by White, Smithwick and Simeone,6 "Usually there is a distinct isthmus between the two halves, the upper component giving off rami to the three lowest cervical nerves, while the lower is connected to the first thoracic nerve by a large and a smaller ramus communicans." It is important to remember that, except in most unusual occasional variations, no further central connections occur above the first thoracic ramus; hence, in blocking the stellate ganglion, the sympathetic supply to the head and upper extremity will be completely interrupted. A variety of methods has been proposed for introducing a needle into, or in the vicinity of, the stellate ganglion. These may be divided into the anterior, anterolateral, lateral and posterior approaches. The champions of each give good reasons for the method they use. We have used both the posterior and anterolateral approach, the latter being utilized in over 90 per cent of our stellate blocks. This is essentially the method described by Ochsner and DeBakey.7 They called it anterior but it is actually anterolateral as the location of the point of entry of the needle in the true anterior approach is considerably more medial. Techniques. Figures 224 and 225 show the two techniques we have found most useful. In the ANTEROLATERAL approach, a point on the skin approximately 4.5 cm. lateral to the midline and 4.5 cm. above the superior margin of the clavicle is selected. In piercing the skin 4.5 cm. above the clavicle, the needle point must be directed slightly inferiorly and medially. This necessary angulation is an additional safeguard against entry into the subarachnoid space. The needle is directed so that it will traverse the tissues just posterior and lateral to the carotid artery and internal jugular vein, piercing the anterior scalene muscle to touch on the most medial aspect of the first rib in the vicinity of the stellate ganglion. When the rib is felt, the needle is withdrawn about 2 mm. and 5 to 10 cc. of 1 per cent procaine is introduced. In the POSTERIOR approach, the needle is introduced approximately 4 cm. from the midline at the level of C6 spinous process in a medial and inferior direction toward the first rib. After contact with themedial aspect of the first rib, the skin marker is adjusted to a distance of 3.5 cm. This will bring the needle tip in the immediate vicinity of the stellate ganglion, when introduced this additional distance. As in all these blocking techniques, careful anesthetization of the skin and the tract to be followed by the needle will enable the procedure to be carried out with almost no discomfort. For the tip of the needle to reach its desired destination, the angulation of the needle from the point of its introduction through the skin is the most important consideration. The location of the head of the first rib must be kept in mind the target. If it is missed on the first introduc-
as
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tion, the needle may be withdrawn and reintroduced at a slightly different angle without any difficulty. If the needle tip is too far lateral and one of the cords of the brachial plexus is struck by it, typical pain radiation will divulge this fact. In utilizing the anterolateral approach, we have had only one instance in which a Horner's syndrome has not been produced.
Painful Upper Extrelllity Syndrollle
Causalgias, post-traumatic syndrome, reflex dystrophy, painful phantom limb and shoulder-hand syndrome can be placed in this general group.
6.<1.""",'" V.
w.~.1/IIII
Fig. 224. Anterolateral approach for stellate ganglion block.
These apparently all have in common some disturbance of the vasomotor system. To those not particularly familiar with this syndrome, patients manifesting these symptoms appear to have a. predisposing underlying psychogenic component. However, it is generally agreed by all who have studied and treated these cases that the so-called psychogenic factor is a result, rather than a cause, of the syndrome and, when the pain is relieved, these manifestations disappear. Mayfield and Devine s state that the personality changes always present during the painful stages are secondary to the pain. There was no evidence in their cases that a predisposing constitutional factor was present.
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An essential feature of the pain of causalgia is its intensification by various stimuli that activate the sympathetic nervous system. This can be manifested by vasoconstriction or vasodilatation. All authors who discuss this syndrome agree that early treatment is imperative. The longer treatment is delayed, the less successful are the results. Trophic changes, atrophy of bones, stiffness of fingers and joints must not be
STELLATE GANGLION
!SiRill
Fig. 225. Posterior approach for stellate ganglion block.
allowed to develop. Procaine block of the sympathetic supply to the extremity is the most valuable initial procedure. In mild cases, one or several blocks may cure the disorder. In the case of recurrence or lessened effect following several blocks, sympathectomy has been found to produce good results in approximately 75 per cent of the cases. For the most part, the various post-traumatic syndromes, other than causalgia, can be lumped into one category and are mostly due to a nonpenetrating injury without an obvious peripheral nerve lesion. Smithwick 9 is of the opinion that these patients are more likely to
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respond to repeated blocks than is the group with causalgia. We recently had a case of this type with excruciating pain of four to five months' duration, following ankle sprain, which was not relieved by lumbar sympathetic block but was relieved by lumbar sympathectomy. However, for the most part, the blocking procedures will give an indication as to the result that may be expected from sympathectomy. Of all the conditions for which treatment by blocking maneuvers have been advocated, this group is one in which it is universally agreed that this therapy is indicated. Cerebral Thrombosis and Embolism
In most of the conditions remaining to be discussed, the efficacy of blocking procedures has strong proponents and opponents. Controversy is particularly sharp regarding the effectiveness of blocking procedures for cerebral thrombosis and embolism. Leriche,lO Searles and N owill, 11 Adams,12 Amyes and Perry,13 Pereira,14 Ruben and Mayer,15 and N affsiger and Adams16 are all strong advocates of the effectiveness of stellate ganglion block for cerebral thrombosis. Denny-Brown17 and Miliken, Lundy and Smith18 believe that blocks for this purpose are ineffective and have no good physiological basis. Controversy centers around the importance of the vasomotor factor in the intracranial vessels. There are conflicting experimental findings on this subject. Such vasomotor component as does exist should be effectively blocked by procainization of the stellate ganglion, as the sympathetic supply carried to the intracranial vessels along the vertebral and internal carotid arteries would be interrupted. Cobb 19 . 20 clearly showed that the cerebral arteries have an autonomic nerve supply in the deep as well as the superficial vessels. However, as Cobb stated, proving that the vasomotor system exists in the brain does not prove that it normally has an important function. How important this mechanism may be to normal function has not yet been determined but the repeated demonstration of a cerebral vasomotor system certainly makes vascular spasm seem a reasonable clinical possibility under pathological conditions, according to Cobb. He also believes that emotional stress may be an important factor in the etiology of cerebrovascular symptoms. Syncope, migraine and convulsions may all be emotionally precipitated; the exact mechanisms are as yet unknown. It is well recognized that spontaneous improvement occurs following cerebral thrombosis and embolism as part of the natural history of the disease. The difficulty in evaluation of a sympathetic nerve blocking procedure of this type is in obtaining control data. One can observe indirect effects of vasodilatation after blocking an extremity and evaluate the procedure partially on this basis. This cannot be done as well with intracranial vessels. We have carried out a number of stellate blocks in this disorder. It is our impression that this procedure is a worthwhile adjunct in certain
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cases in combination with other therapeutic measures commonly employed. One would not expect a good result following block if the occlusion was in the internal carotid or one of the other major arteries any more than one would expect a good result from lumbar sympathetic block in a patient with severe occlusive disease of the femoral or iliac artery in whom adequate collateral circulation was not established in the lower extremity. In other words, there must be a sufficient source of blood to the involved area so that relief of vasospasm may produce an increase of the blood supply. Presumably, in many cases, the vasospastic factor may not be very prominent and in others collateral circulation may not be of sufficient magnitude so that increase in circulation can be obtained after block. Nevertheless, we believe it reasonable to utilize a procedure as innocuous as stellate block as one of the various measures used in the treatment of this disorder until its effectiveness has been definitely disproved. We utilize blocks of 1 per cent procaine on the same side as the cerebral involvement one day apart for two blocks. If these blocks are not followed by increased motor function, by the patient's own evaluation, there is no reason for continuing. If, however, the blocks are apparently effective, continued daily blocks should be used until the maximal effect has been obtained. Some authors have believed that contralateral blocking was helpful in conjunction with ipsilateral blocking. We have done this a few times, but noted no favorable effect from the contralateral block. This procedure is not indicated for treatment in cases of intracranial hemorrhage. Vascular Occlusion with Spasm
In the upper extremity, as is well known, the necessity of therapy for either arterial or venous disease is considerably more infrequent than in the lower extremities. In cases of Raynaud's disease, Buerger's disease and hyperhidrosis, in which there is clearly an indication for interruption of the sympathetic nervous system, stellate ganglion blocks, while occasionally helpful diagnostically, are not indicated therapeutically. Time, money and false hopes can be better saved by proceeding with a dorsal sympathectomy. However, there are instances of vascular disease in which stellate blocks may be extremely helpful in improving the circulation by overcoming the acute vasospastic phenomenon until collateral channels are better established or the affected main vessel relieved of its obstruction. Rarely, thrombosis of the subclavian or brachial artery may occur. Though dorsal sympathectomy, and occasionally amputation, may be the eventual outcome in some instances, stellate block may be an excellent interim therapeutic measure, and in some cases definitive, in conjunction with the usual other measures utilized for relief of arterial occlusion. In instances of embolus of the brachial artery, particularly when accom-
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panied by marked sensory and motor deficiency of the involved extremity, stellate block may be limb saving when combined with embolectomy. When brachial plexus block is elected as an anesthesia, stellate blocks are not necessary as the secondary vasospasm initiated by the primary insult is relieved by paralysis of the vasomotor fibers in conjunction with the regional anesthesia. 21 • 22 For this reason, where not contraindicated, brachial plexus blocks should be utilized more often in conditions requiring operation and accompanied by possible damaging vasospasm in the upper extremity. This principle also holds for spinal anesthesia in treating similar conditions involving the lower extremity. Ochsner and DeBakey23 have been the foremost proponents of the principle of sympathetic block to overcome vasospasm secondary to thrombophlebitis. Occasionally thrombophlebitis with swelling and/or vasospasm may occur in the upper extremity and in such instances the same principles of therapy as enunciated for the lower extremity should be carried out. Various viewpoints concerning the utilization of blocks in conjunction with anticoagulant therapy have been expressed. Hohf, Dye and Julian24 reported two instances of retroperitoneal hemorrhage which they believed were caused by lumbar sympathetic block concomitantly with controlled anticoagulant therapy. Ruben25 also sees a danger in repeated nerve blocking while giving anticoagulant therapy. Pratt,26 on the other hand, does not find any contraindication to concomitant use of anticoagulants and sympathetic nerve blocks in the treatment of vascular lesions. It is his opinion that blocks done correctly, even in the presence of anticoagulant drugs, would not produce dangerous hemorrhage. It has been our practice for a number of years to use intermittent intravenous heparin for anticoagulant therapy and to perform the appropriate sympathetic block about an hour prior to the time for the next intravenous heparin injection. We believe that heparin is a more effective anticoagulant drug than Dicumarol or related agents. According to the severity of the disease process and the sensitivity of the patient to heparin, the time interval of the heparin dose is adjusted, usually either every six hours or every eight hours. The initial dose is usually 75 mg., a sensitivity curve being run after the first dose. The blocks can thereby be adjusted so that danger from hemorrhage will be avoided. Usually blocks are performed every other, or every third day for a series of five or six. Often times two or three blocks will suffice. It has been our feeling that the post phlebitic syndrome can be avoided, or at least lessened, particularly insofar as the swelling is concerned, if blocking procedures l\re carried out during the active phase of the disease in those cases in which vasospasm and/or swelling is present. We would be very loathe to perform blocks on patients who were receiving anticoagulant therapy by mouth or continuous intravenous therapy. Insofar as we are aware, in utilizing the technique of intermittent intravenous
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heparin over a period of seven years, there have been no instances of post-block hemorrhage. There were a few instances of upper extremity involvement demanding sympathetic block in addition to anticoagulant therapy but over 95 per cent of the cases were for involvement of the lower extremity. Meni~re's Disease
The treatment of this disease by interference with the sympathetic nervous system can definitely be said to be in the investigative phase. Johnson et al.2 7 have discussed this matter. Garnett-Passe 28 has reported favorably on his results with sympathectomy for this disease. His results would indicate that upper dorsal sympathectomy is an effective method of treatment. We have treated a number of cases mostly for relief of the symptoms of tinnitus by stellate ganglion blocks and a few by upper dorsal sympathectomy. Although the results have not yet been fully evaluated, it is our impression that further trial should be given this method of therapy if an intensive medical regimen has failed. With the exception of the operation reported by Rosen,29 stellate ganglion blocks and/or upper dorsal sympathectomy are much less extensive and disabling procedures than other methods of surgical therapy. The intracranial operation as advocated by Dandy30 is an operation of considerable magnitude and labyrinthotomy31 is a destructive maneuver followed by deafness on the operated side. The rationale for the sympathetic nervous system approach is based on the theory that the symptoms of Meniere's disease result entirely or partially from vascular disturbance to the inner ear. Should this prove to be the important mechanism in a high percentage of cases, stellate block or upper dorsal sympathectomy would be helpful in certain cases. The same question as pertains to the validity of stellate ganglion block for cerebral thrombosis or embolism might be asked; namely, what amount of sympathetic activity exists in the internal auditory artery and how much of such vasomotor phenomenon, if it is present, can be relieved by blocking sympathetic impulses at the stellate ganglion? We plan to continue investigation of this matter and to treat such cases as are indicated by stellate blocks. Those who obtain relief from multiple blocks will be considered as candidates for upper dorsal sympathectomy, with its more permanent effect, after the entire rationale and possible results have been explained to them. Lewin, in discussing Lathrop's paper32 on the management of Meniere's disease, is in agreement with our views on this matter. Bell's Palsy
Park and Watkins33 have an excellent article on seventh nerve paralysis and comment on their experience in 500 cases. These authors make
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no mention of stellate ganglion block in the treatment of this disease. Swan34 reports two cases thought to be helped by stellate ganglion blocks. Ferris and Martin36 treated seven cases of Bell's palsy by stellate block. Two patients showed no improvement after blocks. Spontaneous recovery has been said to occur in approximately 80 per cent of cases of Bell's palsy. However, in analyzing the recovery factor further, Park and Watkins showed the end result to be related to the time of the initial return of function. Of the 126 patients in whom initial return occurred prior to the third week of the disease, 95 per cent had complete recovery with the remainder being scored as good. Of the 33 patients who had initial return during the fourth to sixth week, 58 per cent had complete recovery, 39 per cent were rated as good and 3 per cent were rated as fair. Of the 43 patients with initial return during the third month, none had complete recovery, 72 per cent were rated good, 23 per cent rated fair and 5 per cent were poor. No patient who waited longer than six months for initial return of function had a satisfactory end result. Residual stigmas were observed in 103 patients. These authors also emphasized that the reaction of degeneration by electrical test gives an estimation of the duration of the paralytic phase of the disease. While 42 patients gave a history of exposure to drafts or colds, Park and Watkins thought that in only one was the exposure of certain significance. However, it is our impression, and the impression of others writing on this subject, that exposure to cold as an exciting cause in the development of this paralysis was elicited in the history more often than would be coincidental. If the paralysis results from swelling of the nerve in its sheath or bony canal and this is accompanied by vasomotor phenomenon, it would seem reasonable to modify this factor by stellate blocks and hence reduce the time interval in which the grotesque disfiguration is present, and possibly thereby bring about more complete final recovery. Multiple stellate blocks two to three times weekly during the initial phases of the paralysis would seem to be a reasonable procedure but not until many more cases are treated can it be fairly evaluated. We have treated only two cases and have been favorably impressed with the results. LUMBAR SYMPATHETIC BLOCKS
Although somewhat more difficult to carry out effectively, and without discomfort, lumbar sympathetic block is performed for conditions of vasomotor imbalance involving the lower extremities similar to those already discussed in the upper extremity for which stellate ganglion block is employed. In the painful lower extremity syndrome, which includes causalgia, post-traumatic syndrome, reflex dystrophy and painful phantom limb, lumbar sympathetic block may be very effective. Cases
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of vascular occlusion with spasm, both arterial and venous, in the lower extremity are treated like similar conditions in the upper extremity. Technique. In the performance of lumbar sympathetic blocks, we use only two needles (Fig. 226). The first is placed approximately 4 cm. from the midline, at the level of the superior border of the spinous process. Following its introduction) direct contact will be made with the transverse process of the second lumbar vertebra. Then the rubber marker is adjusted to a distance of 3.5 cm. from the skin and the tip of the needle is angulated so that it will pass just above the transverse process in a medial direction toward the anterolateral
Fig. 226. Block set for stellate and lumbar ganglia. Gloves, sponge for skin preparation, NOB. 26 and 22 needles for intradermal and subcutaneous injection and two No. 22 needles with skin markers are necessary along with a 2 cc. syringe for introducing procaine in the path to be followed by the needle and a 10 cc. syringe for use when the needle is in place. A ruler is helpful in placing the rubber markers on the needle in the lumbar sympathetic blocks. aspect of the body of the vertebra. Following the introduction of 8 to 10 cc. of 1 per cent procaine, the needle is brought back to the subcutaneous level and redirected so that it now passes just below the second lumbar transverse-process. A similar procedure is carried out with one needle at the third lumbar transverse process (Fig. 227).
In this manner, a high percentage of successful blocks will be accomplished as the chances are increased for effective blockade of an anomalous second lumbar ganglion by this technique. The great anatomical variation of the lumbar sympathetic ganglia is well known. Yeager and Cowley8G have discussed this matter. Only infrequently do central connections exist below the second lumbar outflow; hence, allowing for anatomical variations in the location of the second lumbar ganglion as
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well as the occasional central third lumbar connection, the use of two needles is adequate and effective in blocking the vasomotor outflow to the lower extremity. Crossed connections from right to left or vice versa, is an interesting anatomical variant that must be very rare. This is discussed by KleinSympathetic Chain
M.
If.CI4My"'''''''.
Fig. 227. Lumbar sympathetic block. Each needle is introduced 4 cm. from the midline to the level of L2 and L3 transverse processes. The direction is then changed, and the tip of both needles passed an additional 3.5 cm. in a medial direction both superiorly and inferiorly to the transverse process of L2 and L3.
man37 and mentioned by Yeager and Cowley as accounting for occasional failures following lumbar sympathetic block or sympathectomy. SOMATIC NERVE BLOCKS
We have had no experience in blocking cranial nerves as these procedures should in our opinion be confined to the field of neurosurgery. We have done intercostal nerve block for painful incisions following transthoracic maneuvers. We have also performed these blocks during transthoracic operations in order to prevent the occurrence of painful wounds when portions of the sympathetic system are removed, and have
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employed various techniques of injection of some of the long-lasting agents such as Dolamine, Nupercaine-in-Oil, Efocaine and 5 per cent tannic acid, which generally proved unsatisfactory for this purpose. Our results indicate that neuritis following operations involving removal of portions of the sympathetic nervous system is a more frequent occurrence than after a similar operation without removal of a portion of the sympathetic nervous system. For example, neuritis follows lumbar sympathectomy more frequently than removal of a retroperitoneal tumor in the lumbar region through a similar incision. The explanation of this is obscure although it may be due to some phenomenon connected with sympathetic nerve denervation following operation. Recently we have
NEEDLE INSERTED 7108 CM. FROM MID-LINE
Fig. 228. Intercostal nerve block. A No. 22 needle is inserted approximately 7 to 8 cm. from the midline posteriorly until the rib isfelt. It is then redirected inferiorly just below the rib to an additional distance of 2 to 3 mm.
removed the entire intercostal nerve below the rib resected in the transthoracic approach, and this seems to be helpful in diminishing postoperative pain according to a limited experience. The nerve is resected with the dorsal root ganglion. This is usually followed by a spinal fluid leak. By this method, the problem of regeneration and neuroma formation may be decreased. A technique for paravertebral somatic nerve block is described by Shaw. 38 Unless the posterior division of the nerve is involved, the block can be more simply performed approximately 7 to 8 cm. from the midline posteriorly (Fig. 228). In a few instances, we have noted an increase of the neuritic pain following the nerve blocking maneuver. If intercostal pain becomes intractable and unrelieved by blocking maneuvers, resection of the involved nerve or nerves intraspinally may have to be carried out.
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The use of somatic nerve blocks has been described for a great variety of indications. a9 • 40. 41 In certain cases of severe pruritus vulvae and ani, we have used subcutaneous injection of 1 per cent procaine approximately 4 cm. from the midline around the vulva and anus, confined to the side involved. This is followed by injection of Efocaine through a No. 22 needle. It is emphasized the Efocaine should be deposited in a very fine stream, withdrawing the needle slowly as the injection is started. In this way, there will be no pooling of Efocaine and hence undesirable reactions from slough and infection will be avoided. MISCELLANEOUS
On surveying the literature on this subject, one is impressed by the great variety of conditions for which different authors advocate the use of blocking procedures. Nerve blocks for these various conditions fall into one of three categories: (1) worthless, (2) deserve further investigation and trial, and (3) of definite value. The scope of this paper and our experience does not allow for a separate critique of all these conditions. A few comments will be made, however, concerning our impressions relative to some of them. Bursitis. In bursitis, particularly about the shoulder joint, we have had most satisfactory results following injection therapy into the area as determined by the point of maximal tenderness. We liave usually utilized 1 per cent procaine and approximately 1 cc. of hydrocortisone. We have not used stellate ganglion blocks for this condition but have followed unsuccessful attempts at injection therapy by x-ray treatment to the involved site. Insofar as we are aware, there have been no complications from this type of therapy. Herpes Zoster. In the severe pain of herpes zoster not controlled by the usual methods, blocking the appropriate portion of the sympathetic nervous system may be extremely helpful. In cases of longstanding postherpetic pain, however, we are not impressed with this treatment. Scalenus Anticus Syndrome. Injection therapy for the diagnosis and/or treatment of the scalenus anticus syndrome seems to be of only limited value. The proximity of the anterior scalene muscle to the stellate ganglion must be remembered, as results of injection may be attributed to the muscle infiltration when in fact it is due to sympathetic blockade. Following scalenus infiltration, the Horner's syndrome will give an indication whether or not the ganglion has been blocked in addition to the muscle. Arthritis. Our experience with the injection of procaine, followed by hydrocortisone, in or about painful arthritic joints, has met with sufficient success to cause us to utilize this procedure when the usually recognized more conservative measures have failed to control the joint pain.
George P. Whitelaw
1518 SUMMARY
Our impressions concerning the effectiveness of blocking procedures in certain conditions with which we have had experience has been discussed particularly in reference to the sympathetic nervous :system. Most of this discussion involves the relief of pain syndromes. In 1938, Cutler42 stated that "pain is the symptom that brings most patients to the doctor. There are two types of pain arising through separate mechanisms. There is somatic pain arising in relation to changes in the central nervous system and there is visceral and vascular pain, apparently having to do with changes in the autonomic nervous system. Autonomic or sympathetic pain is capricious; it occurs in a less limited field; it frequently overflows; it varies greatly in intensity with different attacks, is aggravated by the emotions and by barometric pressure and it bears a more distinct relation to the individuality of the patient." The early interest of Cutler and others in this field began to open the trail through a thick forest of ignorance. Further pursuit of this trail is in progress today though we have as yet advanced only a short way. Burdick43 best expresses our attitude toward this whole subject when he says, "It is surprising that the medical profession as a whole is so unaware of the values inherent in therapeutic nerve block procedures. Like all other branches of therapy, it has its shortcomings and its limitations and makes no panacean claims. It has proved its worth in conditions not always responsive to other methods of control. Postponement more than any other factor has mitigated against better results. Its minimal complications in experienced hands and its noninterference with other forms of treatment favor wider adoption. While accomplishment in certain instances leaves much to be desired, the really high percentage of success not only in pain alleviation but in influencing favorably the outcome of disease processes merits more serious consideration." REFERENCES 1. Bonica, J. J.: Management of Intractable Pain with Analgesic Blocks. J.A.M.A 150: 1581-1586, 1952. 2. Adriani, J., Parmley, J. and Ochsner, A.: Fatalities and Complications after Attempts at Stellate Ganglion Block. Surgery 32: 61.5--620, 1952. 3. Rovenstine, E. A. and Papper, E. M.: Therapy of Pain. S. Clin. North America 28: 484-492 (April) 1948. 4. Moore, D. C.: Stellate Ganglion Block-Techniques, Indications, Uses. Springfield, Ill., C. C Thomas, 1954. 5. Martinez, F. A.: The Anatomy of the Stellate Ganglion and Its Surgical Approach. Bull. Georgetown Univ. M. Center 7: 130-135, 1954. 6. White, J. C., Smithwick, R. H. and Simeone, F. A.: The Autonomic Nervous System. 3rd Ed. New York, The Macmillan Co., 1952. 7. Ochsner, A. and DeBakey, M.: Treatment of Thrombophlebitis by Novocaine Block of Sympathetics. Surgery 5: 491, 1939. 8. Mayfield, F. H. and Devine, J. W.: Causalgia. Surg., Gynec. & Obst. 80: 631-635, 1945. 9. Smithwick, R. H.: Post-traumatic Painful Disabling Syndrome with Associated Vasomotor Imbalance. New York State J. Med. 49: 2049-2052, 1949.
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10. Leriche, R.: Treatment of Cerebral Apoplexy and of Its Paralytical Sequelae. Presse Med. 60: 153-172, 1952. 11. Searles, P. W. and Nowill, W. K.: Cerebral Vascular Accidents: Treatment by Stellate Ganglion Blocks. South. M. J. 43: 229-234,1950. 12. Adams, J. E.: Stellate Ganglion Blocking. Surg., Gynec. & Obst. 93: 369-372, 1951. 13. Amyes, E. W. and Perry, S. M.: Stellate Ganglion Block in the Treatment of Acute Cerebral Thrombosis and Embolism. J.A.M.A. lJ,2: 15-20, 1950. 14. Pereira, DeS.: A Blocking of the Middle Cervical and Stellate Ganglia with Descending Infiltration Anesthesia. Arch. Surg. 50: 152, 1945. 15. Ruben, J. E. and Mayer, R. A.: Is Stellate Ganglion Block of Value in Stroke? J.A.M.A. 153: 1004-1007, 1953. 16. Naffsiger, H. C. and Adams, J. E.: ROle of Stellat& Block in Various Intracranial Pathologic States. Arch. Surg. 61: 286-294, 1950. 17. Denny-Brown, D.: The Treatment of Recurrent Cerebrovascular Symptoms and the Question of "Vasospasm." M. CLIN. NORTH AMERICA 85: 1457-1474 (Sept.) 1951. 18. Miliken, C. H., Lundy, J. S. and Smith, L. A.: Evalua.tion of Stellate Ganglion Block for Acute Focal Cerebral Infarcts: Preliminary Report of Obilervations on 87 Patients. J.A.M.A. 151: 43s-441, 1953. 19. Cobb, S.: The Cerebral Circulation: The Relationship of the Cervical Sympathetic Nerves to Cerebral Blood Supply. Am. J. M. Sc. 178: 528, 1929. 20. Cobb, S.: The Cerebral Circulation: Remarks on Clinical Physiology. Ann. Int. Med. 7:292,1933-1934. 21. Humphries, S. V.: Brachial Plexus Block: Report on 350 Cases. Brit. M. J. 1: 163-164,1950. 22. Solnitzky, 0.: Brachial Plexus Block: Bull. Georgetown UDiv. M. Center 7: 121-129 (March) 1954. 23. Ochsner, A. and DeBakey, M.: Treatment of Thrombophlebitis by Novocaine Block of Sympathetics. Surgery 5: 491, 1939. 24. Hohf, R. P., Dye, W. S. and Julian, O. C.: Danger of Lumbar Sympa.thetic Blocks During Anticoagulant Therapy. J.A.M.A. 152: 399-400, 1953. 25. Ruben, J. E.: The Role of Sympathetic Treatment of Chronic Phlebitis and the Postphlebitic Syndrome. Am. Pract. & Dig. Treat. 3: 569-572, 1952. 26. Pratt, G. H.: Anticoagulants and Sympathetic Nerve Blocks in the Treatment of Vascular Lesions: Effective Therapeutic Combination. J.A.M.A. 152: 903-907,1953. 27. Johnson, L. F., Whitelaw, G. P. and Strong, M. S.: Meniere's Disease: A Review, with Comments on Its Treatment by Sympathetic Nervous System Surgery. Boston M. Quart. 4: 106 (March) 1953. 28. Garnett-Passe, E. R.: Sympathectomy in Relation to Meniere's Disease, Nerve Deafness and Tinnitus: A Report on 110 Cases. Proc. Roy. Soc. Med. 44: 760-772, 1951. 29. Rosen, S.: Surgery in Meniere's Disease: A New Operation Which Preserves the Labyrinth: Report of Cases. Ann. Otol., Rhinol. & Laryngol. 60: 657-667, 1951. 30. Dandy, W. E.: Meniere's Disease: Diagnosis and Treatment. Am. J. Surg. 20: 693, 1933. 31. Da.y, K.: Symposium: Surgical Treatment of Hydrops of the Labyrinth: (a) Surgical Destruction of the La.byrinth for Meniere's Disease. Laryngoscope 62: 547-555, 1952. 32. Lathrop, F. D.: Management of Meniere's Syndrome. A.M.A. Arch. Otolaryn. 59: 639-643, 1954. 33. Park, H. W. and Watkins, A. L.: Facial Paralysis: Analysis of 500 Cases. Arch. Phys. Med. 30: 749-763, 1949. 34. Swan, D. M.: Stellate Block in Bell's Palsy. J.A.M.A. 150: 32-33, 1952. 35. Ferris, L. M. and Martin, G. H.: The Use of Sympathetic Nervous Block in the Ambulatory Patient with Special Reference to Its Use in Herpes Zoster. Ann. Int. Med. 32: 257-260, 1950. 36. Yeager, G. H. and Cowley, R. A.: Anatomical Observations on the Lumbar
1520 37. 38. 39. 40. 41.
42. 43.
George P. Whitelaw
Sympathetics in Organic Peripheral Vascular Disease. Ann. Surg. 127: 953967,1948. Kleinman, A.: Causalgia. Evidence of the Existence of Crossed Sensory Sympathetic Fibers. Am. Jour. Surg. 87: 839-841, 1954. Shaw, W. M.: Medial Approach for Paravertebral Somatic Nerve Block. J.A.M.A. 148: 742-744, 1952. Bonica, J. J.: The Management of Pain. Philadelphia, Lea & Febiger, 1953. Solnitzky, 0.: Intercostal Nerve Block. Bull. Georgetown Univ. M. Center 7: 131-141, 1954. Solnitzky, 0.: Meralgia Paresthetica and the Lateral Femoral Cutaneous Nerve. Bull. Georgetown Univ. M. Center 7: 141-145, 1954. Cutler, E. C.: The Surgical Treatment of Pain. New England J. Med. 218: 422426,1938. Burdick, D. L.: Therapeutic Nerve Block in Pain Syndromes of the Aged. Geriatrics 7: 93-98, 1952.
203 Commonwealth Avenue Boston 16, Massachusetts
THIS subject is one of interest to the general practitioner, internist and surgeon alike. Each one frequently encounters problems that might be successfully treated by the utilization of procaine injection. In certain instances, temporary alleviation of symptoms by such methods may point toward more definitive surgical measures, and, in this way, the therapeutic use of procaine is inevitably closely linked with its diagnostic use. However, we will limit this discussion to therapy insofar as possible. Traditionally, surgeons and anesthetists have performed these maneuverso The more complicated procedures should obviously be limited to experienced hands. Nevertheless, there is no reason why internists and general practitioners should not become skilled in their use. For the most part, these injections can be carried out in the office. While primarily general surgeons, Dr. R. H. Smithwick and the surgical group associated with him in the Medical Associates of the Massachusetts Memorial Hospitals have been interested in vascular and sympathetic nervous system surgery. For this reason, a rather wide experience with problems relating to the sympathetic nervous system has accumulated during the past 20 years. A segment of this material will be used as a basis for our discussion of the therapeutic use of procaine injection. During the past three years, we have performed approximately 400 injections of various kinds, both in the office and in the hospital, and approximately 75 per cent have been in relation to the stellate or lumbar sympathetic ganglia. Though procaine blocks are applied more generally to portions of the sympathetic nervous system, other indications for blocking maneuvers have arisen, as will be apparent in the discussion which follows. From the Department of Surgery, Massachusetts Memorial Hospitals and The Boston University School of Medicine, Boston.
* Visiting Surgeon, Massachusetts Memorial Hospitals; Associate Professor of Surgery, Boston University School of Medicine. 1503
George P. Whitelaw
1504 PAIN
While injection therapy has been performed in a few instances for such conditions as cerebral thrombosis, Meniere's disease and Bell's palsy, the symptom of pain is the most common indication for treatment by injection of local anesthetic agents. By definition, painful states are purely a sUbjective phenomenon. To gain objective data during an attack or after its relief is extremely difficult. Although we can utilize skin resistance studies, skin temperatures, plethysmography, electrocardiograms and step tests for preoperative and postoperative treatment evaluation, nevertheless, for the most part one can gain only an estimate of the severity of symptoms before treatment and the effect of any procedure from what the patient himself says. In this type of study, it is recognized that a large margin for error is present in such evaluation and that psychogenic factors may play a role. Analysis of therapeutic results by the statistical method would be almost meaningless in most of these painful conditions. Hence, the evaluation of certain procedures in alleviation of symptoms can best be gained from the composite experience and resultant impressions of a number of individuals. The following discussion will deal with our opinion regard1ng indications, technique and results of those procedures with which we have had experience. Statistical analyses will not be attempted. The efficacy of blocking procedures in certain of the conditions to be discussed are as yet extremely doubtful, some are in the stage of evaluation, while in other conditions the value of this procedure is cleal'-cut and generally accepted. Nerve blocking therapy has been advocated in some conditions for which the indications and rationale are somewhat difficult to discern. An example of this is the use of stellate blocks in Raynaud's disease or hyperhidrosis. Unless the patient's conviction of the efficacy of upper dorsal sympathectomy requires the demonstration of a block during a period of vasospasm, or marked perspiration, one might better proceed with the sympathectomy when clearly indicated. However, this is a relatively new field and procedures which may seem irrational from a physiological standpoint at this time may be found to have a sound basis for their use as our knowledge of etiological mechanisms in some of the disorders broadens. As Bonica1 has mentioned, "It is important to realize that the nerveblock method of managing intractable pain is not completely innocuous and unless one is ready to admit that analgesic blocking has certain limitations, is replete with certain disadvantages, and is not infrequently attended by failure, the results will be disappointing to both patient and physician." SAFEGUARDS IN THE USE OF BLOts:KING AGENTS
Although, in our own experience, we have been fortunate in not encountering a major catastrophe foYowing any blocking procedure, we
The Therapeutic Use of Procaine Hydrochloride Injection
1505
have this possibility constantly in mind and take every precaution to avoid adverse reactions. Potential dangers exist with injection therapy because of the introduction of the needle itself and because of the reaction to the drug used. Even in the most experienced hands, certain reactions may occur to blocking procedures with any drug. The more alarming of these are (1) blood vessel injection, (2) pneumothorax and (3) subarachnoid injection. We have had one partial pneumothorax due to introduction of the needle into the pleura during a stellate block, and three cases of unilateral recurrent laryngeal nerve paralysis. Several reactions have occurred to the procaine itself. Adriani, Parmley and Ochsner2 state that reactions to procaine may be of two varieties, depressive and convulsive, and that barbiturates are helpful in avoiding the convulsive type of reaction. We have had no instances of the convulsive type but have had several depressive reactions with dizziness, lowering of blood pressure and rapid pulse. While Adriani et al. do not feel that barbiturates are helpful in avoiding the depressive reaction, we routinely use 120 mg. (2 grains) of Luminal Sodium subcutaneously prior to any injection in which more than 5 cc. of procaine is to be used. Since this routine has been adopted, the reaction to procaine has practically disappeared. Because of the potential danger of subarachnoid injection, Rovenstine3 advocates that a kit containing the usual resuscitative agents be close at hand when any block is performed. We agree with this advice. Though not completely infallible in avoiding such a calamity, frequent aspirations should be made to determine whether or not the needle tip is in the subarachnoid space when near the intervertebral foramen. This routine should always be observed to avoid the introduction of procaine into a blood vessel as well. As Adriani et a1. 2 have mentioned, an excellent way to determine whether the needle point has been introduced into the pleura is to place a drop or two of the blocking agent into the hub of the needle when disconnecting the syringe. If the patient takes a deep breath, the fluid will either rapidly disappear or be rapidly expelled. This is not infallible either but should be observed when introducing needles near the pleura. STELLATE GANGLION BLOCK
Because of its anatomical relationship to the sympathetic nerve supply of the head, neck and upper extremities, the stellate ganglion is the most important structure to be considered in the over-all use of blocking procedures. Further emphasis has been placed on the importance of this structure since a book, encompassing it as the sole subject, has been published by Moore. 4 As in all portions of the sympathetic nervous system, anatomical variation can occur. Martinez 5 made a special study of the stellate ganglion in this respect and found it may migrate slightly superiorly or
George P. Whitelaw
1506
inferiorly. Having observed the anatomical position of this ganglion on somewhat over 300 different occasions, it is our impression this structure is one of the least variable of all the ganglia. It lies directly anterior to the inner aspect of the first rib near its articulation with the transverse process of the first thoracic vertebra. It is a large structure and may reach a length of 2 cm. The stellate ganglion is a result of fusion of the inferior cervical and first thoracic ganglia and is one single structure of varying shapes. It may be dumbbell in form, cone-shaped or actually stellate. As stated by White, Smithwick and Simeone,6 "Usually there is a distinct isthmus between the two halves, the upper component giving off rami to the three lowest cervical nerves, while the lower is connected to the first thoracic nerve by a large and a smaller ramus communicans." It is important to remember that, except in most unusual occasional variations, no further central connections occur above the first thoracic ramus; hence, in blocking the stellate ganglion, the sympathetic supply to the head and upper extremity will be completely interrupted. A variety of methods has been proposed for introducing a needle into, or in the vicinity of, the stellate ganglion. These may be divided into the anterior, anterolateral, lateral and posterior approaches. The champions of each give good reasons for the method they use. We have used both the posterior and anterolateral approach, the latter being utilized in over 90 per cent of our stellate blocks. This is essentially the method described by Ochsner and DeBakey.7 They called it anterior but it is actually anterolateral as the location of the point of entry of the needle in the true anterior approach is considerably more medial. Techniques. Figures 224 and 225 show the two techniques we have found most useful. In the ANTEROLATERAL approach, a point on the skin approximately 4.5 cm. lateral to the midline and 4.5 cm. above the superior margin of the clavicle is selected. In piercing the skin 4.5 cm. above the clavicle, the needle point must be directed slightly inferiorly and medially. This necessary angulation is an additional safeguard against entry into the subarachnoid space. The needle is directed so that it will traverse the tissues just posterior and lateral to the carotid artery and internal jugular vein, piercing the anterior scalene muscle to touch on the most medial aspect of the first rib in the vicinity of the stellate ganglion. When the rib is felt, the needle is withdrawn about 2 mm. and 5 to 10 cc. of 1 per cent procaine is introduced. In the POSTERIOR approach, the needle is introduced approximately 4 cm. from the midline at the level of C6 spinous process in a medial and inferior direction toward the first rib. After contact with themedial aspect of the first rib, the skin marker is adjusted to a distance of 3.5 cm. This will bring the needle tip in the immediate vicinity of the stellate ganglion, when introduced this additional distance. As in all these blocking techniques, careful anesthetization of the skin and the tract to be followed by the needle will enable the procedure to be carried out with almost no discomfort. For the tip of the needle to reach its desired destination, the angulation of the needle from the point of its introduction through the skin is the most important consideration. The location of the head of the first rib must be kept in mind the target. If it is missed on the first introduc-
as
The Therapeutic Use of Procaine Hydrochloride Injection
1507
tion, the needle may be withdrawn and reintroduced at a slightly different angle without any difficulty. If the needle tip is too far lateral and one of the cords of the brachial plexus is struck by it, typical pain radiation will divulge this fact. In utilizing the anterolateral approach, we have had only one instance in which a Horner's syndrome has not been produced.
Painful Upper Extrelllity Syndrollle
Causalgias, post-traumatic syndrome, reflex dystrophy, painful phantom limb and shoulder-hand syndrome can be placed in this general group.
6.<1.""",'" V.
w.~.1/IIII
Fig. 224. Anterolateral approach for stellate ganglion block.
These apparently all have in common some disturbance of the vasomotor system. To those not particularly familiar with this syndrome, patients manifesting these symptoms appear to have a. predisposing underlying psychogenic component. However, it is generally agreed by all who have studied and treated these cases that the so-called psychogenic factor is a result, rather than a cause, of the syndrome and, when the pain is relieved, these manifestations disappear. Mayfield and Devine s state that the personality changes always present during the painful stages are secondary to the pain. There was no evidence in their cases that a predisposing constitutional factor was present.
1508
George P. Whitelaw
An essential feature of the pain of causalgia is its intensification by various stimuli that activate the sympathetic nervous system. This can be manifested by vasoconstriction or vasodilatation. All authors who discuss this syndrome agree that early treatment is imperative. The longer treatment is delayed, the less successful are the results. Trophic changes, atrophy of bones, stiffness of fingers and joints must not be
STELLATE GANGLION
!SiRill
Fig. 225. Posterior approach for stellate ganglion block.
allowed to develop. Procaine block of the sympathetic supply to the extremity is the most valuable initial procedure. In mild cases, one or several blocks may cure the disorder. In the case of recurrence or lessened effect following several blocks, sympathectomy has been found to produce good results in approximately 75 per cent of the cases. For the most part, the various post-traumatic syndromes, other than causalgia, can be lumped into one category and are mostly due to a nonpenetrating injury without an obvious peripheral nerve lesion. Smithwick 9 is of the opinion that these patients are more likely to
The Therapeutic Use of Procaine Hydrochloride Injection
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respond to repeated blocks than is the group with causalgia. We recently had a case of this type with excruciating pain of four to five months' duration, following ankle sprain, which was not relieved by lumbar sympathetic block but was relieved by lumbar sympathectomy. However, for the most part, the blocking procedures will give an indication as to the result that may be expected from sympathectomy. Of all the conditions for which treatment by blocking maneuvers have been advocated, this group is one in which it is universally agreed that this therapy is indicated. Cerebral Thrombosis and Embolism
In most of the conditions remaining to be discussed, the efficacy of blocking procedures has strong proponents and opponents. Controversy is particularly sharp regarding the effectiveness of blocking procedures for cerebral thrombosis and embolism. Leriche,lO Searles and N owill, 11 Adams,12 Amyes and Perry,13 Pereira,14 Ruben and Mayer,15 and N affsiger and Adams16 are all strong advocates of the effectiveness of stellate ganglion block for cerebral thrombosis. Denny-Brown17 and Miliken, Lundy and Smith18 believe that blocks for this purpose are ineffective and have no good physiological basis. Controversy centers around the importance of the vasomotor factor in the intracranial vessels. There are conflicting experimental findings on this subject. Such vasomotor component as does exist should be effectively blocked by procainization of the stellate ganglion, as the sympathetic supply carried to the intracranial vessels along the vertebral and internal carotid arteries would be interrupted. Cobb 19 . 20 clearly showed that the cerebral arteries have an autonomic nerve supply in the deep as well as the superficial vessels. However, as Cobb stated, proving that the vasomotor system exists in the brain does not prove that it normally has an important function. How important this mechanism may be to normal function has not yet been determined but the repeated demonstration of a cerebral vasomotor system certainly makes vascular spasm seem a reasonable clinical possibility under pathological conditions, according to Cobb. He also believes that emotional stress may be an important factor in the etiology of cerebrovascular symptoms. Syncope, migraine and convulsions may all be emotionally precipitated; the exact mechanisms are as yet unknown. It is well recognized that spontaneous improvement occurs following cerebral thrombosis and embolism as part of the natural history of the disease. The difficulty in evaluation of a sympathetic nerve blocking procedure of this type is in obtaining control data. One can observe indirect effects of vasodilatation after blocking an extremity and evaluate the procedure partially on this basis. This cannot be done as well with intracranial vessels. We have carried out a number of stellate blocks in this disorder. It is our impression that this procedure is a worthwhile adjunct in certain
1510
George P. Whitelaw
cases in combination with other therapeutic measures commonly employed. One would not expect a good result following block if the occlusion was in the internal carotid or one of the other major arteries any more than one would expect a good result from lumbar sympathetic block in a patient with severe occlusive disease of the femoral or iliac artery in whom adequate collateral circulation was not established in the lower extremity. In other words, there must be a sufficient source of blood to the involved area so that relief of vasospasm may produce an increase of the blood supply. Presumably, in many cases, the vasospastic factor may not be very prominent and in others collateral circulation may not be of sufficient magnitude so that increase in circulation can be obtained after block. Nevertheless, we believe it reasonable to utilize a procedure as innocuous as stellate block as one of the various measures used in the treatment of this disorder until its effectiveness has been definitely disproved. We utilize blocks of 1 per cent procaine on the same side as the cerebral involvement one day apart for two blocks. If these blocks are not followed by increased motor function, by the patient's own evaluation, there is no reason for continuing. If, however, the blocks are apparently effective, continued daily blocks should be used until the maximal effect has been obtained. Some authors have believed that contralateral blocking was helpful in conjunction with ipsilateral blocking. We have done this a few times, but noted no favorable effect from the contralateral block. This procedure is not indicated for treatment in cases of intracranial hemorrhage. Vascular Occlusion with Spasm
In the upper extremity, as is well known, the necessity of therapy for either arterial or venous disease is considerably more infrequent than in the lower extremities. In cases of Raynaud's disease, Buerger's disease and hyperhidrosis, in which there is clearly an indication for interruption of the sympathetic nervous system, stellate ganglion blocks, while occasionally helpful diagnostically, are not indicated therapeutically. Time, money and false hopes can be better saved by proceeding with a dorsal sympathectomy. However, there are instances of vascular disease in which stellate blocks may be extremely helpful in improving the circulation by overcoming the acute vasospastic phenomenon until collateral channels are better established or the affected main vessel relieved of its obstruction. Rarely, thrombosis of the subclavian or brachial artery may occur. Though dorsal sympathectomy, and occasionally amputation, may be the eventual outcome in some instances, stellate block may be an excellent interim therapeutic measure, and in some cases definitive, in conjunction with the usual other measures utilized for relief of arterial occlusion. In instances of embolus of the brachial artery, particularly when accom-
The Therapeutic Use of Procaine Hydrochloride Injection
1511
panied by marked sensory and motor deficiency of the involved extremity, stellate block may be limb saving when combined with embolectomy. When brachial plexus block is elected as an anesthesia, stellate blocks are not necessary as the secondary vasospasm initiated by the primary insult is relieved by paralysis of the vasomotor fibers in conjunction with the regional anesthesia. 21 • 22 For this reason, where not contraindicated, brachial plexus blocks should be utilized more often in conditions requiring operation and accompanied by possible damaging vasospasm in the upper extremity. This principle also holds for spinal anesthesia in treating similar conditions involving the lower extremity. Ochsner and DeBakey23 have been the foremost proponents of the principle of sympathetic block to overcome vasospasm secondary to thrombophlebitis. Occasionally thrombophlebitis with swelling and/or vasospasm may occur in the upper extremity and in such instances the same principles of therapy as enunciated for the lower extremity should be carried out. Various viewpoints concerning the utilization of blocks in conjunction with anticoagulant therapy have been expressed. Hohf, Dye and Julian24 reported two instances of retroperitoneal hemorrhage which they believed were caused by lumbar sympathetic block concomitantly with controlled anticoagulant therapy. Ruben25 also sees a danger in repeated nerve blocking while giving anticoagulant therapy. Pratt,26 on the other hand, does not find any contraindication to concomitant use of anticoagulants and sympathetic nerve blocks in the treatment of vascular lesions. It is his opinion that blocks done correctly, even in the presence of anticoagulant drugs, would not produce dangerous hemorrhage. It has been our practice for a number of years to use intermittent intravenous heparin for anticoagulant therapy and to perform the appropriate sympathetic block about an hour prior to the time for the next intravenous heparin injection. We believe that heparin is a more effective anticoagulant drug than Dicumarol or related agents. According to the severity of the disease process and the sensitivity of the patient to heparin, the time interval of the heparin dose is adjusted, usually either every six hours or every eight hours. The initial dose is usually 75 mg., a sensitivity curve being run after the first dose. The blocks can thereby be adjusted so that danger from hemorrhage will be avoided. Usually blocks are performed every other, or every third day for a series of five or six. Often times two or three blocks will suffice. It has been our feeling that the post phlebitic syndrome can be avoided, or at least lessened, particularly insofar as the swelling is concerned, if blocking procedures l\re carried out during the active phase of the disease in those cases in which vasospasm and/or swelling is present. We would be very loathe to perform blocks on patients who were receiving anticoagulant therapy by mouth or continuous intravenous therapy. Insofar as we are aware, in utilizing the technique of intermittent intravenous
1512
George P. Whitelaw
heparin over a period of seven years, there have been no instances of post-block hemorrhage. There were a few instances of upper extremity involvement demanding sympathetic block in addition to anticoagulant therapy but over 95 per cent of the cases were for involvement of the lower extremity. Meni~re's Disease
The treatment of this disease by interference with the sympathetic nervous system can definitely be said to be in the investigative phase. Johnson et al.2 7 have discussed this matter. Garnett-Passe 28 has reported favorably on his results with sympathectomy for this disease. His results would indicate that upper dorsal sympathectomy is an effective method of treatment. We have treated a number of cases mostly for relief of the symptoms of tinnitus by stellate ganglion blocks and a few by upper dorsal sympathectomy. Although the results have not yet been fully evaluated, it is our impression that further trial should be given this method of therapy if an intensive medical regimen has failed. With the exception of the operation reported by Rosen,29 stellate ganglion blocks and/or upper dorsal sympathectomy are much less extensive and disabling procedures than other methods of surgical therapy. The intracranial operation as advocated by Dandy30 is an operation of considerable magnitude and labyrinthotomy31 is a destructive maneuver followed by deafness on the operated side. The rationale for the sympathetic nervous system approach is based on the theory that the symptoms of Meniere's disease result entirely or partially from vascular disturbance to the inner ear. Should this prove to be the important mechanism in a high percentage of cases, stellate block or upper dorsal sympathectomy would be helpful in certain cases. The same question as pertains to the validity of stellate ganglion block for cerebral thrombosis or embolism might be asked; namely, what amount of sympathetic activity exists in the internal auditory artery and how much of such vasomotor phenomenon, if it is present, can be relieved by blocking sympathetic impulses at the stellate ganglion? We plan to continue investigation of this matter and to treat such cases as are indicated by stellate blocks. Those who obtain relief from multiple blocks will be considered as candidates for upper dorsal sympathectomy, with its more permanent effect, after the entire rationale and possible results have been explained to them. Lewin, in discussing Lathrop's paper32 on the management of Meniere's disease, is in agreement with our views on this matter. Bell's Palsy
Park and Watkins33 have an excellent article on seventh nerve paralysis and comment on their experience in 500 cases. These authors make
The Therapeutic Use of Procaine Hydrochloride Injection
1513
no mention of stellate ganglion block in the treatment of this disease. Swan34 reports two cases thought to be helped by stellate ganglion blocks. Ferris and Martin36 treated seven cases of Bell's palsy by stellate block. Two patients showed no improvement after blocks. Spontaneous recovery has been said to occur in approximately 80 per cent of cases of Bell's palsy. However, in analyzing the recovery factor further, Park and Watkins showed the end result to be related to the time of the initial return of function. Of the 126 patients in whom initial return occurred prior to the third week of the disease, 95 per cent had complete recovery with the remainder being scored as good. Of the 33 patients who had initial return during the fourth to sixth week, 58 per cent had complete recovery, 39 per cent were rated as good and 3 per cent were rated as fair. Of the 43 patients with initial return during the third month, none had complete recovery, 72 per cent were rated good, 23 per cent rated fair and 5 per cent were poor. No patient who waited longer than six months for initial return of function had a satisfactory end result. Residual stigmas were observed in 103 patients. These authors also emphasized that the reaction of degeneration by electrical test gives an estimation of the duration of the paralytic phase of the disease. While 42 patients gave a history of exposure to drafts or colds, Park and Watkins thought that in only one was the exposure of certain significance. However, it is our impression, and the impression of others writing on this subject, that exposure to cold as an exciting cause in the development of this paralysis was elicited in the history more often than would be coincidental. If the paralysis results from swelling of the nerve in its sheath or bony canal and this is accompanied by vasomotor phenomenon, it would seem reasonable to modify this factor by stellate blocks and hence reduce the time interval in which the grotesque disfiguration is present, and possibly thereby bring about more complete final recovery. Multiple stellate blocks two to three times weekly during the initial phases of the paralysis would seem to be a reasonable procedure but not until many more cases are treated can it be fairly evaluated. We have treated only two cases and have been favorably impressed with the results. LUMBAR SYMPATHETIC BLOCKS
Although somewhat more difficult to carry out effectively, and without discomfort, lumbar sympathetic block is performed for conditions of vasomotor imbalance involving the lower extremities similar to those already discussed in the upper extremity for which stellate ganglion block is employed. In the painful lower extremity syndrome, which includes causalgia, post-traumatic syndrome, reflex dystrophy and painful phantom limb, lumbar sympathetic block may be very effective. Cases
1514
George P. Whitelaw
of vascular occlusion with spasm, both arterial and venous, in the lower extremity are treated like similar conditions in the upper extremity. Technique. In the performance of lumbar sympathetic blocks, we use only two needles (Fig. 226). The first is placed approximately 4 cm. from the midline, at the level of the superior border of the spinous process. Following its introduction) direct contact will be made with the transverse process of the second lumbar vertebra. Then the rubber marker is adjusted to a distance of 3.5 cm. from the skin and the tip of the needle is angulated so that it will pass just above the transverse process in a medial direction toward the anterolateral
Fig. 226. Block set for stellate and lumbar ganglia. Gloves, sponge for skin preparation, NOB. 26 and 22 needles for intradermal and subcutaneous injection and two No. 22 needles with skin markers are necessary along with a 2 cc. syringe for introducing procaine in the path to be followed by the needle and a 10 cc. syringe for use when the needle is in place. A ruler is helpful in placing the rubber markers on the needle in the lumbar sympathetic blocks. aspect of the body of the vertebra. Following the introduction of 8 to 10 cc. of 1 per cent procaine, the needle is brought back to the subcutaneous level and redirected so that it now passes just below the second lumbar transverse-process. A similar procedure is carried out with one needle at the third lumbar transverse process (Fig. 227).
In this manner, a high percentage of successful blocks will be accomplished as the chances are increased for effective blockade of an anomalous second lumbar ganglion by this technique. The great anatomical variation of the lumbar sympathetic ganglia is well known. Yeager and Cowley8G have discussed this matter. Only infrequently do central connections exist below the second lumbar outflow; hence, allowing for anatomical variations in the location of the second lumbar ganglion as
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well as the occasional central third lumbar connection, the use of two needles is adequate and effective in blocking the vasomotor outflow to the lower extremity. Crossed connections from right to left or vice versa, is an interesting anatomical variant that must be very rare. This is discussed by KleinSympathetic Chain
M.
If.CI4My"'''''''.
Fig. 227. Lumbar sympathetic block. Each needle is introduced 4 cm. from the midline to the level of L2 and L3 transverse processes. The direction is then changed, and the tip of both needles passed an additional 3.5 cm. in a medial direction both superiorly and inferiorly to the transverse process of L2 and L3.
man37 and mentioned by Yeager and Cowley as accounting for occasional failures following lumbar sympathetic block or sympathectomy. SOMATIC NERVE BLOCKS
We have had no experience in blocking cranial nerves as these procedures should in our opinion be confined to the field of neurosurgery. We have done intercostal nerve block for painful incisions following transthoracic maneuvers. We have also performed these blocks during transthoracic operations in order to prevent the occurrence of painful wounds when portions of the sympathetic system are removed, and have
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George P. Whitelaw
employed various techniques of injection of some of the long-lasting agents such as Dolamine, Nupercaine-in-Oil, Efocaine and 5 per cent tannic acid, which generally proved unsatisfactory for this purpose. Our results indicate that neuritis following operations involving removal of portions of the sympathetic nervous system is a more frequent occurrence than after a similar operation without removal of a portion of the sympathetic nervous system. For example, neuritis follows lumbar sympathectomy more frequently than removal of a retroperitoneal tumor in the lumbar region through a similar incision. The explanation of this is obscure although it may be due to some phenomenon connected with sympathetic nerve denervation following operation. Recently we have
NEEDLE INSERTED 7108 CM. FROM MID-LINE
Fig. 228. Intercostal nerve block. A No. 22 needle is inserted approximately 7 to 8 cm. from the midline posteriorly until the rib isfelt. It is then redirected inferiorly just below the rib to an additional distance of 2 to 3 mm.
removed the entire intercostal nerve below the rib resected in the transthoracic approach, and this seems to be helpful in diminishing postoperative pain according to a limited experience. The nerve is resected with the dorsal root ganglion. This is usually followed by a spinal fluid leak. By this method, the problem of regeneration and neuroma formation may be decreased. A technique for paravertebral somatic nerve block is described by Shaw. 38 Unless the posterior division of the nerve is involved, the block can be more simply performed approximately 7 to 8 cm. from the midline posteriorly (Fig. 228). In a few instances, we have noted an increase of the neuritic pain following the nerve blocking maneuver. If intercostal pain becomes intractable and unrelieved by blocking maneuvers, resection of the involved nerve or nerves intraspinally may have to be carried out.
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The use of somatic nerve blocks has been described for a great variety of indications. a9 • 40. 41 In certain cases of severe pruritus vulvae and ani, we have used subcutaneous injection of 1 per cent procaine approximately 4 cm. from the midline around the vulva and anus, confined to the side involved. This is followed by injection of Efocaine through a No. 22 needle. It is emphasized the Efocaine should be deposited in a very fine stream, withdrawing the needle slowly as the injection is started. In this way, there will be no pooling of Efocaine and hence undesirable reactions from slough and infection will be avoided. MISCELLANEOUS
On surveying the literature on this subject, one is impressed by the great variety of conditions for which different authors advocate the use of blocking procedures. Nerve blocks for these various conditions fall into one of three categories: (1) worthless, (2) deserve further investigation and trial, and (3) of definite value. The scope of this paper and our experience does not allow for a separate critique of all these conditions. A few comments will be made, however, concerning our impressions relative to some of them. Bursitis. In bursitis, particularly about the shoulder joint, we have had most satisfactory results following injection therapy into the area as determined by the point of maximal tenderness. We liave usually utilized 1 per cent procaine and approximately 1 cc. of hydrocortisone. We have not used stellate ganglion blocks for this condition but have followed unsuccessful attempts at injection therapy by x-ray treatment to the involved site. Insofar as we are aware, there have been no complications from this type of therapy. Herpes Zoster. In the severe pain of herpes zoster not controlled by the usual methods, blocking the appropriate portion of the sympathetic nervous system may be extremely helpful. In cases of longstanding postherpetic pain, however, we are not impressed with this treatment. Scalenus Anticus Syndrome. Injection therapy for the diagnosis and/or treatment of the scalenus anticus syndrome seems to be of only limited value. The proximity of the anterior scalene muscle to the stellate ganglion must be remembered, as results of injection may be attributed to the muscle infiltration when in fact it is due to sympathetic blockade. Following scalenus infiltration, the Horner's syndrome will give an indication whether or not the ganglion has been blocked in addition to the muscle. Arthritis. Our experience with the injection of procaine, followed by hydrocortisone, in or about painful arthritic joints, has met with sufficient success to cause us to utilize this procedure when the usually recognized more conservative measures have failed to control the joint pain.
George P. Whitelaw
1518 SUMMARY
Our impressions concerning the effectiveness of blocking procedures in certain conditions with which we have had experience has been discussed particularly in reference to the sympathetic nervous :system. Most of this discussion involves the relief of pain syndromes. In 1938, Cutler42 stated that "pain is the symptom that brings most patients to the doctor. There are two types of pain arising through separate mechanisms. There is somatic pain arising in relation to changes in the central nervous system and there is visceral and vascular pain, apparently having to do with changes in the autonomic nervous system. Autonomic or sympathetic pain is capricious; it occurs in a less limited field; it frequently overflows; it varies greatly in intensity with different attacks, is aggravated by the emotions and by barometric pressure and it bears a more distinct relation to the individuality of the patient." The early interest of Cutler and others in this field began to open the trail through a thick forest of ignorance. Further pursuit of this trail is in progress today though we have as yet advanced only a short way. Burdick43 best expresses our attitude toward this whole subject when he says, "It is surprising that the medical profession as a whole is so unaware of the values inherent in therapeutic nerve block procedures. Like all other branches of therapy, it has its shortcomings and its limitations and makes no panacean claims. It has proved its worth in conditions not always responsive to other methods of control. Postponement more than any other factor has mitigated against better results. Its minimal complications in experienced hands and its noninterference with other forms of treatment favor wider adoption. While accomplishment in certain instances leaves much to be desired, the really high percentage of success not only in pain alleviation but in influencing favorably the outcome of disease processes merits more serious consideration." REFERENCES 1. Bonica, J. J.: Management of Intractable Pain with Analgesic Blocks. J.A.M.A 150: 1581-1586, 1952. 2. Adriani, J., Parmley, J. and Ochsner, A.: Fatalities and Complications after Attempts at Stellate Ganglion Block. Surgery 32: 61.5--620, 1952. 3. Rovenstine, E. A. and Papper, E. M.: Therapy of Pain. S. Clin. North America 28: 484-492 (April) 1948. 4. Moore, D. C.: Stellate Ganglion Block-Techniques, Indications, Uses. Springfield, Ill., C. C Thomas, 1954. 5. Martinez, F. A.: The Anatomy of the Stellate Ganglion and Its Surgical Approach. Bull. Georgetown Univ. M. Center 7: 130-135, 1954. 6. White, J. C., Smithwick, R. H. and Simeone, F. A.: The Autonomic Nervous System. 3rd Ed. New York, The Macmillan Co., 1952. 7. Ochsner, A. and DeBakey, M.: Treatment of Thrombophlebitis by Novocaine Block of Sympathetics. Surgery 5: 491, 1939. 8. Mayfield, F. H. and Devine, J. W.: Causalgia. Surg., Gynec. & Obst. 80: 631-635, 1945. 9. Smithwick, R. H.: Post-traumatic Painful Disabling Syndrome with Associated Vasomotor Imbalance. New York State J. Med. 49: 2049-2052, 1949.
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10. Leriche, R.: Treatment of Cerebral Apoplexy and of Its Paralytical Sequelae. Presse Med. 60: 153-172, 1952. 11. Searles, P. W. and Nowill, W. K.: Cerebral Vascular Accidents: Treatment by Stellate Ganglion Blocks. South. M. J. 43: 229-234,1950. 12. Adams, J. E.: Stellate Ganglion Blocking. Surg., Gynec. & Obst. 93: 369-372, 1951. 13. Amyes, E. W. and Perry, S. M.: Stellate Ganglion Block in the Treatment of Acute Cerebral Thrombosis and Embolism. J.A.M.A. lJ,2: 15-20, 1950. 14. Pereira, DeS.: A Blocking of the Middle Cervical and Stellate Ganglia with Descending Infiltration Anesthesia. Arch. Surg. 50: 152, 1945. 15. Ruben, J. E. and Mayer, R. A.: Is Stellate Ganglion Block of Value in Stroke? J.A.M.A. 153: 1004-1007, 1953. 16. Naffsiger, H. C. and Adams, J. E.: ROle of Stellat& Block in Various Intracranial Pathologic States. Arch. Surg. 61: 286-294, 1950. 17. Denny-Brown, D.: The Treatment of Recurrent Cerebrovascular Symptoms and the Question of "Vasospasm." M. CLIN. NORTH AMERICA 85: 1457-1474 (Sept.) 1951. 18. Miliken, C. H., Lundy, J. S. and Smith, L. A.: Evalua.tion of Stellate Ganglion Block for Acute Focal Cerebral Infarcts: Preliminary Report of Obilervations on 87 Patients. J.A.M.A. 151: 43s-441, 1953. 19. Cobb, S.: The Cerebral Circulation: The Relationship of the Cervical Sympathetic Nerves to Cerebral Blood Supply. Am. J. M. Sc. 178: 528, 1929. 20. Cobb, S.: The Cerebral Circulation: Remarks on Clinical Physiology. Ann. Int. Med. 7:292,1933-1934. 21. Humphries, S. V.: Brachial Plexus Block: Report on 350 Cases. Brit. M. J. 1: 163-164,1950. 22. Solnitzky, 0.: Brachial Plexus Block: Bull. Georgetown UDiv. M. Center 7: 121-129 (March) 1954. 23. Ochsner, A. and DeBakey, M.: Treatment of Thrombophlebitis by Novocaine Block of Sympathetics. Surgery 5: 491, 1939. 24. Hohf, R. P., Dye, W. S. and Julian, O. C.: Danger of Lumbar Sympa.thetic Blocks During Anticoagulant Therapy. J.A.M.A. 152: 399-400, 1953. 25. Ruben, J. E.: The Role of Sympathetic Treatment of Chronic Phlebitis and the Postphlebitic Syndrome. Am. Pract. & Dig. Treat. 3: 569-572, 1952. 26. Pratt, G. H.: Anticoagulants and Sympathetic Nerve Blocks in the Treatment of Vascular Lesions: Effective Therapeutic Combination. J.A.M.A. 152: 903-907,1953. 27. Johnson, L. F., Whitelaw, G. P. and Strong, M. S.: Meniere's Disease: A Review, with Comments on Its Treatment by Sympathetic Nervous System Surgery. Boston M. Quart. 4: 106 (March) 1953. 28. Garnett-Passe, E. R.: Sympathectomy in Relation to Meniere's Disease, Nerve Deafness and Tinnitus: A Report on 110 Cases. Proc. Roy. Soc. Med. 44: 760-772, 1951. 29. Rosen, S.: Surgery in Meniere's Disease: A New Operation Which Preserves the Labyrinth: Report of Cases. Ann. Otol., Rhinol. & Laryngol. 60: 657-667, 1951. 30. Dandy, W. E.: Meniere's Disease: Diagnosis and Treatment. Am. J. Surg. 20: 693, 1933. 31. Da.y, K.: Symposium: Surgical Treatment of Hydrops of the Labyrinth: (a) Surgical Destruction of the La.byrinth for Meniere's Disease. Laryngoscope 62: 547-555, 1952. 32. Lathrop, F. D.: Management of Meniere's Syndrome. A.M.A. Arch. Otolaryn. 59: 639-643, 1954. 33. Park, H. W. and Watkins, A. L.: Facial Paralysis: Analysis of 500 Cases. Arch. Phys. Med. 30: 749-763, 1949. 34. Swan, D. M.: Stellate Block in Bell's Palsy. J.A.M.A. 150: 32-33, 1952. 35. Ferris, L. M. and Martin, G. H.: The Use of Sympathetic Nervous Block in the Ambulatory Patient with Special Reference to Its Use in Herpes Zoster. Ann. Int. Med. 32: 257-260, 1950. 36. Yeager, G. H. and Cowley, R. A.: Anatomical Observations on the Lumbar
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42. 43.
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Sympathetics in Organic Peripheral Vascular Disease. Ann. Surg. 127: 953967,1948. Kleinman, A.: Causalgia. Evidence of the Existence of Crossed Sensory Sympathetic Fibers. Am. Jour. Surg. 87: 839-841, 1954. Shaw, W. M.: Medial Approach for Paravertebral Somatic Nerve Block. J.A.M.A. 148: 742-744, 1952. Bonica, J. J.: The Management of Pain. Philadelphia, Lea & Febiger, 1953. Solnitzky, 0.: Intercostal Nerve Block. Bull. Georgetown Univ. M. Center 7: 131-141, 1954. Solnitzky, 0.: Meralgia Paresthetica and the Lateral Femoral Cutaneous Nerve. Bull. Georgetown Univ. M. Center 7: 141-145, 1954. Cutler, E. C.: The Surgical Treatment of Pain. New England J. Med. 218: 422426,1938. Burdick, D. L.: Therapeutic Nerve Block in Pain Syndromes of the Aged. Geriatrics 7: 93-98, 1952.
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