420

THE AN/ESTHETIST'S ROLE IN DIAGNOSIS AND THERAPEUTICS.

By DOUGLAS WILSON (LondondelTy).

A S anaesthetists, we are all conscious of the improvements in the technique of administration of amestheties in the theatre, but are we equally aware of the methods at our disposal by which we can

be of the greatest assistance to our medical and surgical colleagues? I refer to the value of the diagnostic and therapeutic applications of" ana~thesia, and I thought it would be appropriate to review with you some of the facts, with a few personal experiences.

The Auto~wmic Nervous System. Undoubtedly, diseases of the autonomic nervous system form a large

section upon which the anaesthetist can apply his specialised knowledge. To do this requires an understanding of its anatomy and physiology.

The autonomic or involuntary nervous system is arranged on exactly the same lines as the somatic spinal reflex. I t has, therefore, three components, viz., an afferent neurone, connector cell and neurone, and an exeitor neurone.

The afferent neurone proceeds from an internal organ to its nutrient cell, which lies in the posterior root ganglion, whence it emits a central process to the lateral horn of the grey matter. Here it synapses with the connector cell and neurone.

The connector cell is situated in the lateral horn, and with its neurone connects the afferent with the excitor neurone, the latter supplying the viscera and the smooth muscle of vessels. It must be noted that the exeitor cells, where the connector neurone terminates, have migrated without the C.N.S. to form masses of cells situated peripherally. Con- sequently, the connector fibres leave the C.N.S. to reach these cells, and are called "preganglionic, medullated, white rami communieantes "

The excitor cells lie peripherally, either as isolated groups of cells or as definite ganglia. From these cells the excitor fibres arise as non- medullated, postganglionic, grey rami communicantes. One connector neurone can synapse with numerous excitor cells.

Connector fibres arise in the following regions: 1. In the brain, in connection with the nuclei of 3rd, 7th, 9th,

10th cranial nerves. 2. in the whole of the thoracic region. 3. In the 1st, 2nd, and possibly 3rd lumbar segments. 4. In the 2nd, 3rd, and 4th sacral segments.

The cranial plus the sacral autonomic systems constitute the para- sympathetic, while the thoracicolumbar outflow (connector plus exeitor fibres) make up the sympathetic proper.

With reference to the sympathetic system, it will be seen, therefore, that the vasoconstrictor fibres emerge from the lateral horn of the cord as white rami, to relay in the ganglia of the sympathetic chain. Here

* Communication to Section of Anaesthetics, March 14th, 1951

THE AN2ESTHETIST'S ROLE IN DIAGNOSIS 421

the axons of the next relay arise and travel as grey rami to the spinal nerves, together with which they are distributed to the periphery, send- ing off branches to the smooth muscle of the arteries throughout their length. It is important to note that the sympathetic system exhibits the characteristic of a diffuse discharge, owing to the fact that a single preganglionic axon synapses with numerous postganglionic neurones.

There are no white rami above T1 or below L2, and all preganglionic fibres are given off between these two levels.

Head and Neck. The fibres for this region run upwards in the sympathetic chain for several segments to reach the cervical ganglia, where the postganglionic fibres arise.

Arm. Bareroft and Hamilton, 1 who did much to clarify the sympathetic supply of the upper limb, concluded that the sympathetic supply to this area arises in the upper thoracic cord, and passes by white rami to the 2nd and 3rd thoracic sympathetic ganglia. In these two ganglia the next relay arises and passes up the sympathetic chain to the stellate ganglion. They emphasise the point that, while some fibres of this relay end in the stellate ganglion, the greater number pass through. From the stellate, fibres pass direct to the upper part of the axillary artery and others are distributed to the vessels of the arm via the brachial plexus.

Quite often a small branch from the 2nd thoracic ganglion, glorified by the name of the nerve of Kuntz, '~ runs direct to the lowest trunk of the brachial plexus. It is therefore logical, when it is necessary to paralyse the entire constrictor supply of the arm and thereby obtain the maximum vasodilatation, to block the 1st and 2nd thoracic sympathetic ganglia.

I f the stellate alone is blocked, the nerve of Kuntz escapes; if the brachial plexus alone is blocked, the fibres going direct to the axillary artery escape.

Leg. Preganglionic fibres to this part arise from the lower thoracic and upper lumbar cord. A few pass as white rami to the 2nd and 3rd lumbar ganglia, whence the postganglionic fibres arise and run to the vessels of the thigh; the majority, however, end in ganglia below L2, which they reach by passing down the sympathetic chain, as there are no white rami in this area. Postganglionic fibres arise from the lower lumbar sympathetic ganglia, and pass to the vessels of the leg via the spinal nerves, in main the sciatic.

An effective block of the 2nd and 3rd lumbar ganglia will interfere with all vasoconstrictor fibres to the lower limb.

Bearing in mind these anatomical and physiological facts relevant to the sympathetic system, we are now in a position to consider some of the more common conditions and the appropriate steps which can be taken by the anmsthetist in diseases of this system.

Vazospasm. From the anmsthetist's point of view, sympatheetomy can be divided into two groups, viz., (a) permanent and surgical (very occasionally chemical), and (b) chemical and temporary.

There are many peripheral vascular disorders, in which the lesion is chiefly due to spasm of the arteries, and can be improved or cured by a permanent sympathectomy. In these cases, the anaesthetist can perform two important duties : firstly, he can forecast with fair accuracy by his

422 IRISH JOURNAL OF MEDICAL SCIENCE

chemical sympathectomy the probable result of surgery, and secondly, after the surgical sympathectomy, he can furnish the surgeon with information regarding the completeness of his operation, and at a later date, if need be, ascertain whether there has been any sympathetic regeneration. 3

Instances of such diseases are Raynaud's disease, intermittent claudica- tion, hyperhidrosis, acrocyanosis and hypertension.

When an artery is organically occluded, there will, of course, be little or no response to the therapeutic sympathectomy.

The second group of chemical or temporary sympathectomy is of far greater interest and importance to the anaesthetist for, by its appropriate and timely application, he can save many a patient from permanent crippling (white leg) or even loss of a limb.

The slightest degree of trauma can cause reflex arteriolar spasm, or, as Leriche, 4 0 c h s n e r and DeBakey 5, e pointed out in their classical experiments on venous thrombosis, that in thrombophlebitis, vasocon- strictor appliances are initiated from the affected segment of vein and are carried over the sympathetic nervous system, producing spasm of the arterioles in the homolateral extremity. This reflex spasm, which is so easily arrested by a single or repeated sympathetic block, if untreated, can cause a dangerous vicious circle.

Vasospasm Vasoconstriction

Pressure

Deficient oxygenation of tissues (pain)

L Damage to capillary endo~holium t

I ~Oedema

I should like to describe three typical cases referred to me.

CASE 1.--D. S., ~et. 37 years, has been gett ing " cold feet " for last l l years. Right foot very much worse than left, with symptoms of in te rmi t ten t claudication. Call only walk about 100 yards, when he has to stop with pain in r ight foot. Toes of right foot blueish. No pulsations felt in r ight posterior tibial and dorsaIis podia arteries. Referred to me on August, 1950 for r ight paravertebral block, which I did, using 40 o.e. 1 per cent. procaine. Immediate flushing of toes, and was sent for half-mile walk up hill without return of symptoms of intermit tent elaudieation. The t reatment was repeated on August 4th and 7th, 1950, when he was seen in conjunction with his surgeon and was told to report if he thought he was not improving. To this date he is doing well.

CASE 2 . - -A young naval officer, ~et. 25 years, reported with the history that he was playing golf one evening and awakened next morning with a most painful, swollen, blue left hand. He was seen by his surgeon, who sent him to me with a diagnosis of deep vein thrombosis of the axillary vein, ? traumatic. On examination hfs hand was codematous, blue and finger movements nil. Radial pulse not palpable. .

I performed a left paravertebral block of T1-2, using 30 c.e. 1 per cent. procaine, with the most satisfying result.

Within 10 minutes the arm and hand were flushed, there was a feeling of warmth, and within 20 minutes there was full recovery of finger movements. I=~e was given a sling, and by the next day all the codema had disappeared and the hand appeared normal. He returned to full du ty in 48 hours with complete and permanent recovery.

This case proved two points : - - 1. The efficacy of a sympathet ic block done in good time. 2. That the naval officer understood the principles of golf by working his left

hand.

THE ANAESTHETIST'S ROLE IN DIAGNOSIS 423

CASE 3.--E. B., mr. 25 years, had a normal delivery of a 6½ lb. baby on April 4th, 1950, and until April l l t h puerperium continued withou~ event. On April 12th, she was referred to me by th~ obstetr ician with a painful, swollen right leg, movements nil, temperature 103 ° F. and pulse 104. There w~s a palpable vein in the right calf with an accentuated Honan"s sign. Arterial pulsations not palpable in foot.

I performed a right paravertebral block with 40 c.c. 1 per cent. procaine, after which heparin therapy was started. Within 15 minutes there was an almost complete relief of symptoms. Satisfactory progress wa~ maintained and she was discharged on April 23rd, 1950.

The points of interest in a case of thrombophlebitis, such as this, are that concomitant with the relief of the vasospasm there is also relief of pain, subsidence of the fever, and disappearance of the ¢edema.

Ochsner ~ has proved that the cedema is due to the occlusion of the vein not by the thrombus, but by the accompanying vasospasm. He demonstrated the fact that surgical ligation of a vein will not produce ~edema, and that by temporary chemical sympathectomy the cedema subsides, although the thrombus still remains. The fever, he says, probably abates owing to the fact that there is more rapid resolution of the inflammatory process in the wall of the vein, resulting from the increased vascularisation.

Technique af Sympathetic Release.

There are several methods of obtaining a sympathetic block, but the most commonly used are:

1. The posterior approach of Kappis, bearing in mind the fact that the sympathetic trunk in the thoracic region is more lateral than anterior, while in the lumbar region it is more anterior than lateral, in relation to the bodies of the vertebrae.

2. Paravertebral block is by far the most common method employed. It is worth noting that the paravertebral space is in reality a lateral continuation of the epidural space, where there exists a negative pressure. Consequently, when a needle is placed correctly in the paravertebral space, and later when aspiration is performed through a syringe contain- ing the solution, air bubbles are extracted. This is known as the " aspiration bubbles '.' test of Kerr2

I would also like to point out that it is advisable, when performing a sympathetic block for venous thrombosis, to do it before any anti- coagulant therapy is started, and, if the latter has been commenced, to use as few puncture sites as possible. There is the very real danger of a h~ematoma developing. A retroperitoneal h~ematoma is not an uncommon complication in these cases. According to Ochsner, ~ 90 per cent. of the eases of thrombophlebitis are cured after the first injection, while the remaining 10 per cent. need a second injection.

3. Subarachnaid block. Sarnoff, Arrowood and co-workers, 1°-1'~ con- centrating on hypertensive patients, have devised a technique of differential spinal block by using a sufficiently dilute solution of 0"2 per cent. procaine hydrochloride in 0-85 per cent. solution of sodium chloride. This causes paralysis of the vasomotor, sudomotor and pilomotor fibres, and leaves other fibres untouched.

4. Caudal block. Ruben, TM at the instigation of Waters, determined tho weakest concentration of local analgesic agent which, when placed in the epidural space, would consistently block sympathetic vasocon-

424 IRISH JOURNAL OF MEDICAL SCIENCE

stricter impulses. He has reported 27 cases of successful block for peripheral vascular disease using 20 c.c. of Amethocaine 0-02 per cent. injected at regular intervals through a ureteric catheter in the caudal canal.

He has also had success in 45 cases using 0"1 per cent. solution procaine similarly. In none of these ambulatory patients was there interference with micturition, def~ecation, locomotion or sensory loss.

IntestinaZ Dyskinesi~. I would like to pass now to a brief consideration of the intestinal

dyskinesire, with particular reference to Hirschsprung's disease. There are several conditions, such as cardiospasm, mega-cesophagus,

Hirschsprung's disease, and the postoperative paralytic ileus, in which the evidence suggests that the temporary but complete paralysis of the sympathetic supply to the affected parts, the sympathetic being inMbi- tory to the gut, may, as Hewer ~7 says, bring the two halves of the autonomic nervous system once more into step.

From the anaesthetist's point of view, there are two recognised methods of attack on Hirsehsprung's disease:

1. Bilateral splanchnic blovk, as recommended by Seholefield and Chivers, 18 with which they reported an 80 per cent success rate.

2. High spinal to the level of T5. The block may have to be repeated. Motor activity of the bowel should be encouraged by enemata following the block, and it is stated that it may take 10 to 14 days after the block before the bowel recovers its tone.

CAg~ 1 . - - I recall the ease of a boy, 8 years old, admit ted to hospital on December 23rd, 1948. He had had attacks of umbilical pain and vomiting, on and off since t h e ago of 2 years, and these had become far worse during the last year, with incontinence of solid f~eces. I~e spent the summer in the Nervou~ Diseases Hospital, from w h e r e he was discharged with the label of a " nervous child." The surgeon's notes read : " Hard masses along right side of abdomen.? Enlarged colon with f~eces. P . R . - - masses of solid f~eees in spite of recent bowel evacuation. Barium enema confirms megacolon.' '

On December, 29th, 1948, under cover of a basal narcosis with rectal paraldehyde, I gave him a high spinal, using Howard Jones ' formula of P D--4, with 11 e.c. of 1/1500 nupercaine. After this, with daily enemata, he recovered bowel tone and was dis- charged on January, 10th, 1949.

All went well until February, 1949, when he had an at tack of tonsillitis which set him back with less of bowel tone once again. He was readmit ted to hospital on March 17th, the t reatment repeated, and was discharged on March 28th. To this day he is well and regular in his bowel habit.

CASE 2 . - - In 1944, I had a soldier at death 's door with paralytic ileus following an appendieectomy for a perforated appendix with general peritonitis. All hope of his survival had been given up, when I was asked by the surgeon whether I would give him a high spinal. With nothing to lose and everything to gain, I consented to this rather terrifying ordeal with, I am glad to say, a gratifying result. There was an almost immediate evacuation of flatus with fluid fmcal matter: Thereafter, the tone of his gut, although poor for a few days, was maintained. I-Ie recovered completely. He was given continuous oxygen, not only for his poor condition, but in the hope th at it would help to relieve the distended gut.

The modern literature suggests that in such a case it may be beneficial, using the differential spinal technique of Sarnoff and Arrowood, to maintain a continuous spinal block with 0"2 per cent. procaine and thus produce the necessary "sympathetic release effect " without affecting the somatic motor nerves.

There are numerous other instances where blocking the appropriate

THE ANAESTHETIST'S ROLE IN DIAGNOSIS 425

sympathetic pathway may prove of therapeutic or diagnostic value. I quote, for instance:

1. Blocks of the stellate or upper thoracic ganglia) ~ which have been used in :

a. Mdni~re's syndrome, where the symptoms may be due to vaso- spasm of the internal auditory branch of the anterior inferior eerebellar artery.

b. Restoration of vision, due to spasm of the retinal artery, due to thrombosis of one of its branches.

c. Angina pectoris, which may be relieved by a left-sided para- vertebral block of T1-4; the vasoconstrictor fibres passing through these ganglia, and the pain pathway through the corresponding posterior spinal roots.

d. So also the pain of a thoracic aneurysm. (T1-4.) e. Paroxysmal tvxhycardia. f. Asthma, with varying results by alleviating the bronchospasm. g. Certain pathological conditions of the arm and hand, e.g., causal-

gia, reflex sympathetic dystrophy, subdeltoid bursitis, and in particular the " shoulder-hand syndrome"

Friedman 2° divides the progress of the shoulder-hand syn- drome into three stages:

1. Pain and limitation of movement in the shoulder, with pain and swelling of the hand.

2. Relief of pain and diminution of swelling. 3. Irreversible stage of atrophy, contracture and osteoporosis

of fingers. If these cases are treated early in Stage 1, excellent results

are guaranteed. h. Acute pulmonary embolism, 2~ when the block is done on the side

of the maximum pain. Reflexes initiated by the embolus can cause serious cardiac distur-

bances, including arterial and bronchospasm in all parts of both lungs. Abajian 22 concludes that some of these reflexes have their afferent path- ways over the sympathetics and the efferents over the vagus, while others have both afferent and efferent pathways over the sympathetics, and advises blocking the stellate ganglion.

2. In the trunk, a bilateral paravertebral block of T12 and L1 has proved a useful method of relieving the reflex vasospasm of the arteries of the renal cortex, which Trueta 23 and others demonstrated occurs in such conditions as crush syndrome, incompatible transfusion, yellow fever, tox~emia of pregnancy, Wiel's disease, and after operation on the urogenital tract.

A similar block (T12-L2) on the affected side will bring amazing relief to a patient, agonised with pain from renal colic, by releasing the spasm of the smooth muscle of the ureter.

right-sided P.V. block of T8-11 (inc.), will abolish pain due to gall-bladder disease.

Terminal Cancer. The prevention of pain is the anmsthetist's most important duty, and his services may be invaluable in making the closing days of a doomed patient tolerable. The terminal stages of a pelvic or abdominal cancer may be marked by intolerable pain, upon which the

426 IRISH JOURNAL OF MEDICAL SCIENCE

most potent pain-relieving drugs have little or no action. In such eases an intrathecal injection of absolute alcohol may have to be con- sidered. The injection is made at the appropriate level, the dose injected is 1 e.c. and it takes about two minutes to complete the injection. Absolute alcohol is hypobaric.

Kenny 24 has reported success in this field using caudal proetocaine in doses of 40-60 c.c., and it is a method for which I have preference.

White and Smithwick 25 have advocated repeated splanchnic blocks or surgical resection of the splanchnic nerves for such cases.

Crymotherapy, or therapy by cold, is not new. Such agents as C02 snow, ethyl chloride spray, cold compresses and cool sponging have had a recognised place in treatment for many years. Lake 2s stimulated interest in the application of cold as a possible therapeutic measure in cases of trench foot.

Allen 27 has aroused further interest in this subject in more recent years. He showed that refrigeration analgesia was an excellent technique for the amputation of limbs in poor risk patients, e.g., diabetic and arteriosclerotic gangrenes, and, in cases where survival rather than removal of tissue is the objective, crymotherapy, by lowering the metabolism of tissues which have a deficient blood supply, helps to keep the tissues alive while a collateral circulation develops.

Muscle Relaxants. With the introduction of the muscle relaxants, a new therapeutic field has been opened. They are used extensively to soften the fits of eleetroconvulsive therapy, for which purpose Bennett first used curare. Various nervous disordel~ associated with spasticity have been kept in cheek, and the prognosis for tetanus has improved considerably by the usage of these drugs. 2g, 29, 3o

Intravenous Therapy. Numerous methods of intravenous therapy have been used, but the most publicised during recent years is that of intravenous procaine. This I will not discuss, as I am sure all anaes- thetists must have given it their full consideration.

One technique worthy of note, however, is that of the use of 7"5 per cent. ethyl alcohol, 5 per cent. protein hydrolysate and 5 per cent. dex- trose solution to provide the calorific requirements of a patient under basal conditions together with analgesia. 31 It is one which I feel may get great attention in the future, as the only complication encountered is inebriation due to rapid administration ; which is of minor significance. 200 c.c. are given initially in 25-30 minutes and the remaining 800 c.c. are given over 4 hours. To intensify the analgesic properties of the solution, 1 gramme of procaine hydrochloride to 1,000 c.c. may be added if required.

There are numerous other therapeutic and diagnostic measures, too lengthy to mention now, which are used by the anaesthetist, but I trust that in this cursory review I have been successful in refreshing your memories of how we, as anaesthetists, can play an important role outside the operating theatre.

I would like to t hank m y surgical colleagues and friends, ltiessrs. J . G. Pyper, H. M. Bennet t , and S. W. Liggett for all the co-operation they have given me, and my resident anaesthetist Dr. J. C. Clarke, for keeping m y records.

References. 1. Barcroft, H. & Hamilton, G. T .C . LanceS, 1 ; 441. (1948). 2. Woolmer, R. P.R.S.M., 42 ; 3 : 123. (1949).

ELECTROCARDIOGRAPHIC CHANGES 427

3. Barcroft, I-I. and Hamil ton, G. T. C. Lancet, 1 ; 441. (1948). 4. Leriche, R. J . Internat. d~ Chit., 3; 585-598. (1938). 5. Oehsner, A. and DeBakey, M. Surgery, 5; 491-497. (1939). 6. Ochsner, A. and DeBakey, M. J. Amer. Med. Assoc., 114 ; 117-124. (1940). 6. Ochsner, A. and DeBakey, M. J. Amer. Med. Assoc., 114 ; 117-124. (1940), 8. Kerr , G. 1~I. P.R .S .M. , 42; 3 ; 133. (1949). 9. Ochsner, A. and DeBakey, M. J. Amer. Med. Assoc., 114 ; 117-124. (1940).

10. Sarnoff, S. J. and Arrowood, J . G . Surgery, 20 ; 150. (1946). 11. Sarnoff, S . J . J . Clin. Invest., 26; 203. (1947). 12. Sarnoff, S. J. J. Neurophyslol., 10; 205. (1947). 13. Sarnoff, S. J. and Chapman, W. P. Surg. Gyn. Obst., 86; 571. (1948). 14. Sarnoff, S. J. and .~Lrrowood, J . G . Anesthesiology, 9 ; 614. (1948). 15. Arrowood, J . G . P.R .S .M. , 43; 11; 919. (1950). 16. Ruben, g. E. Anesth. and Analg., 29; 296-297. (1950). 17. Hewer, (3. L. Recent Advances in Anesthesia, p. 190. (1944). 18. Sholefield, J. and Chivers, E. Brit. J. Ances., 20 ; 84. (1947). 19. Woolmer, 1%. P.R .S .M. , 42; 3 ; 124. (1949). 20. Fr iedman, H. If., e t al. Anesth. and Analg., 27; 273-278. (1948). 21. Anderson, R. i~I., e t al. Ancsth. and Analg., 29 ; 315-329. (1950). 22. Abajian, J. Anesth. and Analg., 29; 323. {1950). 23. Trueta , J. , e t al. Lancet, 2; 237. (1946). 24. Kenny, M. Brit. Med. J., 2 ; 862. (1947). 25. ~Vhite, J . C. and Smithwiek, R. The Autonomic Nervous System. New York.

The Macmillan Company. (1945). 26. Lake, N . C . Lancet, 2 ; 557. (1917). 27. Allen, F. l~I. Anesth. and Anal9., 24; 51-65. (1945). 28. Hunte r , A. R. and Waterfall , J. ]~f. Lancet, 1 ; 366. (1948). 29. Belfrage, D . H . Lancet, 11; 889. (1947). 30. Keir, R. Brit. Med. J . , 2 ;; 984. {1950). 31. Grabill, F. J., Hackmuth , L., Tuohy, E . B . Anesth. and Analg., 29 ; 211-216.

(1950).

ELECTROCARDIOGRAPHIC CHANGES F O L L O W I N G MITRAL VALVULOTOMY. ~

By S~.XN P. 0'TOOLE.

T H E electrocardiographic pattern in mitral stenosis largely depends on hypertrophy and enlargement of the left atrium and right ventricle. In some cases in which enlargement of these chambers

is minimal, the electrocardiogram may be normal or at most may show slight P wave abnormalities and right axis deviation.

In the more advanced cases with severe pulmonary hypertension the changes are more marked, and signs of right ventricular hypertrophy and strain become apparent. Cardiac catheterisation studies by Bayliss et al. (1950) have shown that there is a striking correlation between the presence of a very high pulmonary arterial pressure and electrocardio, graphic evidence of right ventricular hypertrophy.

The purpose of this report is to present the electrocardiographic features of four patients who were subjected to mitral valvulotomy and to point out the changes which occurred following operation. The serial tracings are shown in Figures 1, 2, 3 and 4, and the significant changes which occurred are outlined in Figure 5.

° F r o m the Cardiac D e p a r t m e n t , Wes te rn Regiona l S a n a t o r i u m .