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Selective Gastric Vagotomy
Selective Gastric Vagotomy CHARLES A. GRIFFITH, M.D., F.A.C.S.*
There is geographically scattered enthusiasm for selective vagotomy and pyloroplasty for duodenal ulcer. Reports are largely still at the anumerical testimonial stage and the majority of surgeons are watching the returns with caution. There is no evidence that this technically more tedious operation, with its threat of incomplete section, is superior to total vagectomy.-EIsEMAN (1965) It is to be hoped that the current interest in "selective vagotomy" will not provide a shelter for those surgeons who are unable to find and resect the right vagus.-MOORE (1963) Observation and study over a prolonged period of time will be necessary before one can determine whether or not selective vagotomy is followed by a lower incidence of such an infrequent sequela as diarrhea, and at the same time is not accompanied by an increased incidence of incomplete gastric vagotomy and recrudescent peptic ulcer.-WooDWARD AND EISENBERG (1965) Finally, although proponents of selective vagotomy have emphasized that the completeness of gastric denervation is more certain in the selective teehnique, enough doubt exists to prevent widespread use of this more difficult operation, regardless of the proposed advantages of this procedure.-BALDwIN, ALBO, JAFFE AND SILEN (1965)
In view of these criticisms against selective gastric vagotomy, the rebuttal will be stated at the outset. Selective gastric vagotomy poses two entirely separate and unrelated issues: (1) the safe and successful achievement of complete gastric vagotomy, and (2) the effects of hepatic and celiac vagotomy upon viscera other than the stomach. Of these two issues, the first is clearly the more important. Consequently, of primary concern are the criticisms that selective gastric vagotomy will prove technically too difficult and hazardous, and that it will increase the rate of incomplete gastric vagotomy. So far as I know, these criticisms come only from surgeons who have never evaluated the selective technique. In my experience, however, learnFrom the Department of Surgery, University of Washington School of Medicine, Seattie, Washington * Clinical Associate Professor of Surgery
367
368
CHARLES
A.
GRIFFITH
ing the anatomic principles of selective gastric vagotomy has been synonymous with learning the anatomic principles of complete gastric vagotomy. Furthermore, depending upon the specific operative circumstances, these anatomic principles may be applied in performing either selective gastric or total abdominal vagotomy. In either case, consistently successful results of complete gastric vagotomy have been achieved to date. This experience is by no means unique. In personal discussions with other surgeons who have also evaluated the selective technique in this country and in Great Britain, I have found unanimous agreement concerning the cardinal advantage of achieving complete gastric vagotomy. The advantage of the selective technique in assuring complete gastric vagotomy is best appreciated by comparing the selective technique with conventional techniques. The essential difference is that the selective technique applies constant anatomic landmarks, whereas conventional techniques do not.
CONVENTIONAL TECHNIQUES
The evolution of Dragstedt's operation has been summarized by Dragstedt II (1961). I shall therefore quote liberally from his account. When Dragstedt introduced vagotomy, the complications of gastric stasis were unknown. He performed only vagotomy per se, and chose the transthoracic approach because it "afforded an excellent exposure of the vagus nerves and made it possible to transect them before they had bifurcated extensively at the esophageal hiatus." When the need for gastric drainage became apparent, Dragstedt switched to the transabdominal approach in order to perform a concomitant drainage procedure. Transabdominal vagotomy was performed at the esophageal hiatus, and entailed an attempt to transect all vagal fibers as they emerged through the hiatus. However, the rate of incomplete vagotomy "rose substantially over what it had been when the transthoracic approach was used. This occurred because the vagus nerves branch widely just above the esophageal hiatus, and hence many small fibers were overlooked." Consequently, Dragstedt devised his present technique of transabdominal supradiaphragmatic vagotomy. From within the abdomen he incises the diaphragm just anterior to the hiatus, and through this counterincision of the diaphragm encircles the esophagus and vagi above the hiatus. "In this manner the vagus nerves can be identified and transected while they are still in two main trunks." The Problem of Incomplete Vagotomy
In evaluating Dragstedt's technique, Woodward (1959) concluded, "The major disadvantage is the unavoidably rather high incidence of in-
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complete vagotomy." The obvious difficulty is that the vagus nerves do not always exist as two main trunks at or above the hiatus. As described by Dragstedt (1962), "In about 50 per cent of cases, only two large trunks are seen; in the remaining 50 per cent, the anterior vagus nerve may be represented by two or more branches and in a small number the right or posterior vagus may be found as two or more trunks." Consequently, instead of conducting the operation with confidence that two and only two main trunks are present, we actually have no confidence whatsoever as to how many trunks there are or where they are. We transect only those we can find, and are left wondering if we have found them all. This, as I see it, is the real problem of incomplete vagotomy. In order to solve this problem-and it can be solved-we must first recognize the vagal system as a system independent of the diaphragm.
The Fallacy of the Diaphragm as the Anatomic Landmark From the left and right vagus nerves below the pulmonary plexus to the abdominal viscera, the vagal system consists of three constant components: (1) the esophageal plexus, which varies from a few large fibers in its simplest form to many small fibers in its most complex form; (2) two and only two main trunks, one anterior and one posterior; and (3) four truncal divisions, the hepatic, the celiac, and the anterior and posterior gastric divisions. This system has no anatomic relationship with the diaphragm, but descends through the hiatus in the form of anyone of its three constant components. The variable occurrence of the vagal system at the hiatus as the esophageal plexus or the trunks or the truncal divisions explains the variable occurrence of multiple nerves at the hiatus (Fig. 1). Two additional points pertain. First, full appreciation of the anatomic concept diagrammed in Figure 1 requires many dissections of the vagal system as a system in continuity from the thorax through the hiatus to the abdomen. It is an anatomic impossibility to recognize the vagal system as the esophageal plexus or the trunks or the truncal divisions in dissections confined to the hiatus or just above the hiatus. Second, and not readily apparent in Figure 1, the positions of the fibers of the esophageal plexus and the trunks and the truncal divisions are extremely variable at and above the hiatus. Not only may they lie in any of the 360 degrees around the circumference of the esophagus, but they may lie in variable positions away from the esophagus as well. In point of fact, above the hiatus some fibers may be closer to the aorta and mediastinal pleura than to the esophagus, and at the hiatus some fibers may be closer to the hiatal margins and aorta than to the esophagus.
The Unavoidable Pitfall At and Above the Hiatus Dragstedt has repeatedly emphasized the importance of a meticulous disseetion that lays bare the longitudinal muscle of the encircled esophagus in search of small nerves that may be lurking within the esophageal muscu-
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Right
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GRIFFITH
Left
nerve
A
Figure 1. The Vagal System and the Hiatus. A. The vagal system descends through the hiatus at A as the esophageal plexus, at B as the 2 trunks, and at C as the 4 truncal divisions.
B
Hepatic division
C
Celiac division
laris or fascia propria. However, despite this meticulous search (and despite complete transection of the esophagus in animals), incomplete vagotomy may still occur, and it occurs because the dissection does not guarantee identification and encirclement of all vagal fibers with the encircled esophagus. In dissections confined to the region of the hiatus, as is the case with either the conventional transabdominal technique or the transabdominal supradiaphragmatic technique, we are always confronted by an unknown component of the vagal system consisting of unknown numbers of nerves in unknown positions. Under these circumstances, in the attempt to encircle with the esophagus all vagal fibers that may be present, the encircling finger may blindly exclude one or more fibers, and thus completely displace them out of the surgical field. With emphasis upon finding and transecting all nerves in only the tissue that has been encircled with the esophagus, the nerves excluded from the encircled tissue are never looked for and never transected-at least not at the first operation. At the second operation however, performed by the technique to be described shortly, large intact nerves are found lying in virgin tissue well outside the operative scar around the esophagus. It is inconceivable that any experienced surgeon could overlook such large fibers, provided that he encircled these fibers with the esophagus and brought them into his surgical field at the first operation. The crux of the matter is this: no anatomic landmarks are available to prevent or recognize the error of excluding one or more vagal fibers when they are encircled at or above the hiatus. Thus a variable but certain occurrence of incomplete vagotomy is indeed unavoidable with conventional techniques.
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THE HEPATIC AND CELIAC VAGAL DIVISIONS: KEYS TO ENCIRCLEMENT OF ALL VAGAL FIBERS TO THE STOMACH
The hepatic and celiac divisions are the only two constant landmarks in the entire vagal system below the pulmonary plexus that may be applied to guarantee complete encirclement of all vagal fibers to the stomach. The third constant landmark is the angle of His-i.e., the crotch between the left aspect of the esophagus and the right aspect of the fundic dome of the stomach. By using these three landmarks, the operation starts not at the level of the hiatus but at a level well below it-namely, the gastric cardia. At this lower level of the cardia, and only at this lower level, do all gastric vagal fibers gather to innervate the stomach along its lesser curve. The hepatic vagal division is the landmark on the patient's right. It
can always be seen, even in obese patients, when the lesser omentum is stretched out by upward retraction of the left lobe of the liver and downward retraction of the stomach. The clearest view is obtained by visualizing the caudate lobe of the liver through the stretched-out fat-free transparent lesser omentum, and seeing the gray opaque hepatic fibers within the lesser omentum contrasted against the dark background of the caudate lobe. By incising the lesser omentum in its avascular area below the hepatic division and to the right of the gastric cardia, we can be certain of including all gastric vagal fibers on the right. No fibers reach the stomach to the right of this incision in the lesser omentum. * The landmark on the patient's left is the angle of His. By snipping the peritoneum over this angle, and introducing the finger into the crotch between the esophagus and gastric fundus, we can be certain of including all gastric vagal fibers on the left. No gastric fibers reach the fundus to the left of this incision in the peritoneum at the angle of His. By working through the incision in the lesser omentum below the hepatic vagal division on the right, and through the incision in the peritoneum at the angle of His on the left, we feel for the posterior landmarkthe posterior vagal trunk and its continuation as the celiac division. Although the position of the celiac division varies in the dorsal-ventral plane between the left gastric artery and right diaphragmatic crus, we can always identify it by palpation, particularly when it is stretched out and rendered tense by downward retraction of the stomach. The celiac division is always a large cord, readily felt and traced by palpation to its constant destination at the celiac plexus. By dissecting the finger through the tissue posterior to the celiac division, we encircle the celiac division with the esophagus. In
* Fibers of the hepatic vagal division go to the porta hepatis, where they enter the autonomic hepatic plexus. Dissections in some but not all cadavers demonstrate small fibers from the hepatic plexus descending with the right gastric vessels to the most distal antrum, pylorus and proximal duodenum. The function of these fibers is unknown. Their electric stimulation in dogs does not elicit any gastric contraction. When these fibers are left intact in patients with selective vagotomy and pyloroplasty, insulin hypoglycemia does not elicit free acid. Their function is most probably afferent sensory.
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Hepatic division
Celiac division
Figure 2. The Encirclement of All Vagal Fiber8 to the Stomach. As indicated by the arrow, all gastric vagal fibers may be encircled at once or, if preferred, in stages-first, the anterior fibers for anterior vagotomy, and second, the posterior fibers with the esophagus for posterior vagotomy.
this manner we may and perhaps often do exclude posteriorly some small celiac fibers to the bowel and pancreas, but we always include all fibers to the stomach. No gastric fibers lie in a position posterior to the celiac division (Fig. 2). By means of this technique, we gain positive anatomic assurance that the finger encircles all gastric vagal fibers with the esophagus. Furthermore, in my hands at least, encircling all gastric vagal fibers by this technique is just as easy and quick and safe as the conventional transabdominal technique at the hiatus, and is easier and quicker and safer than the transabdominal supradiaphragmatic technique above the hiatus. A soft rubber catheter or drain next replaces the encircling finger to maintain exposure. The operation now proceeds according to the choice of selective gastric or total abdominal vagotomy.
SELECTIVE GASTRIC VAGOTOMY OR TOTAL ABDOMINAL VAGOTOMY
Elsewhere in this symposium our Guest Editor, Dr. Ballinger, discusses the effects of hepatic and celiac vagotomy upon viscera other than the stomach. I believe these effects are important, particularly when both hepatic and celiac vagotomy are complete. As incomplete gastric vagotomy may occur, so may incomplete hepatic and incomplete celiac vagotomy occur. Unfortunately, we have no tests for completeness of hepatic and celiac vagotomy, and therefore are more or less thwarted in our efforts to study this problem. Although the evidence is still controversial, I believe that hepatic and celiac vagotomy is neither necessary nor desirable, and therefore perform selective gastric vagotomy whenever operative circumstances permit.
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Anatomic and technical details of selective vagotomy have been previously published (Griffith, 1962, 1964). Rather than repeat these details I shall discuss the issue of technical difficulty. Selective gastric vagotomy requires a more extensive and meticulous dissection than total abdominal vagotomy. In my initial experience I therefore selected thin patients undergoing elective operation, and did not encounter any particular difficulties or hazards. As experience increased I gradually extended the operation to include more obese patients, and have continued to do so. However, total abdominal vagotomy is often the wiser choice for some obese or poor-risk patients.
Anterior Vagotomy Anterior selective vagotomy entails transection of all tissue anterior to the esophagus-from the incision in the lesser omentum beneath the hepatic division on the right, to the incision in the peritoneum at the angle of His on the left. This tissue contains all anterior gastric vagal fibers plus small branches of the esophageal vessels, and therefore is transected between clamps. This dissection lays bare the entire anterior surface of the esophagus. Anterior selective vagotomy is usually technically easy. Three circumstances may occasionally pose difficulties. The first is adhesions plastering the stomach to the under surface of the liver. The second is the occurrence (10 to 15 per cent) of a large accessory or replacing left hepatic artery from the left gastric artery. When present, this aberrant left hepatic artery runs just below and very close to the hepatic vagal division in the lesser omentum to the porta hepatis. Third, in some patients the fibers of the hepatic division arise quite low, just above the cardia, and care must be taken to preserve them. Although they may be preserved, total anterior vagotomy is easier because the tissue anterior to the esophagus may be transected without regard for low lying hepatic fibers.
Posterior Vagotomy The performance of posterior selective vagotomy requires positive identification of the posterior trunk and celiac division. This requirement is all-important, for it eliminates the most common error resulting in incomplete vagotomy-namely, missing the posterior trunk. As previously described, the posterior trunk and celiac division may be identified by palpation when the vagal fibers are initially encircled with the esophagus. However, this maneuver becomes easy only by doing it. If not initially identified and encircled, the posterior trunk and celiac division must be located after anterior vagotomy is completed (Legend, Fig. 2). Location of the posterior trunk and celiac division in the surgical field following anterior selective vagotomy is much easier than in the more limited field following anterior total vagotomy. Posterior selective vagotomy entails transection of all tissue between
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the posterior vagal trunk and celiac division on the right, and the esophagus and proximal lesser curve of the stomach on the left. Because some posterior gastric vagal fibers reach the stomach via the left gastric artery in some patients (Jackson, 1948), the left gastric artery must be transected and ligated adjacent the lesser curve. For surgeons experienced in gastric resection, posterior selective vagotomy is usually not particularly hazardous or difficult. However, as with gastric resection we must protect an aberrant left hepatic artery. Posterior selective vagotomy obviously requires a more extensive dissection than posterior total vagotomy, particularly in the obese patient. Dissection of the Esophagus
Selective gastric vagotomy essentially entails transection of all tissue that has been encircled except the hepatic and celiac divisions and the esophagus. Total abdominal vagotomy leaves only the esophagus. Although not diagrammed in Figure 1, small gastric vagal fibers may occasionally arise not from their respective truncal divisions but independently from the trunks or esophageal plexus above. These small independent gastric fibers usually lie in the esophageal fascia propria, and are transected by a final dissection that lays bare the longitudinal muscle of the esophagus. Fibers occasionally felt within the esophageal muscle are esophageal fibers, I believe, and therefore need not be transected by dissections that violate the integrity of the esophageal muscle.
ADEQUATE AND INADEQUATE INCOMPLETE GASTRIC VAGOTOMY
Although the rates of recurrent ulcer and incomplete vagotomy vary from series to series, the rate of incomplete vagotomy is always higher than the rate of recurrent ulcer. In studying patients with incomplete vagotomy by means of the insulin and histamine tests, the positive responses of gastric acid vary in degree from weakly to strongly positive. Patients with strongly positive responses are the ones who develop recurrent ulcer, and therefore their incomplete vagotomy is inadequate. Patients with weakly positive responses may not develop recurrent ulcer, and therefore their incomplete vagotomy is adequate. This discrepancy of different physiologic degrees of incomplete vagotomy is most probably due to different anatomic types of incomplete vagotomy. Vagotomy does not obey the all-or-none phenomenon. Failure to transect a large fiber of the esophageal plexus or an entire trunk or an entire gastric division is quite different from failure to transect a small independent gastric fiber supplying only a small portion of stomach. Furthermore, the amount of vagal reinnervation by sprouting (Murray, 1959) most probably is influenced by the anatomic type of incomplete vagotomy. In Dragstedt's recent experience (1962), he reports a 2 per cent rate of
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inadequate incomplete vagotomy. This exceedingly low rate is in the hands of the master, however, and in less expert hands the rate is notoriously higher. I am convinced that this high rate of inadequate incomplete vagotomy may be significantly lowered by encircling all fibers to the stomach as previously described, because in doing so there is a minimal or even no chance of missing a large branch of the esophageal plexus or a large trunk or an entire gastric division.
THE COMPLEMENTARY PROCEDURE
Exclusive of ulcerogenic pancreatic tumor, Dragstedt propounds that the ulcer will heal, and remain healed, if (1) gastric vagotomy is adequate, and (2) gastric drainage is adequate. The only real challenge to this thesis is that by Kay (1962), who proposes that a few patients with adequate vagotomy and adequate drainage will develop recurrent ulcer due to unusual potential of the retained antrum and parietal cell mass. Only time will prove or disprove the validity of Kay's proposal. At the present time, all other available experimental and clinical evidence indicates that Dragstedt's thesis is standing the test of time and is correct. Dragstedt (1962) performs Weinberg's modification of the HeinekeMikulicz pyloroplasty or, if pyloroplasty appears hazardous, gastrojejunostomy in the antrum 4 to 6 cm. from the pylorus, and with a stoma not greater than 1.5 cm. (to minimize dumping). These two drainage procedures are not infallible in preventing gastric stasis. In point of fact, in Dragstedt's current experience gastric stasis is a more common cause of recurrent ulcer than incomplete vagotomy. Drainage of the vagotomized stomach by pyloroplasty is not only influenced by the size of the stoma in relation to the size of the duodenal lumen, but is also influenced by the position of the stoma in relation to the most dependent portion of the stomach as well. Although there is as yet no clear-cut clinical evidence indicating the superiority of one pyloroplasty over all others, the Finney pyloroplasty seems superior,. because when performed as described by Finney, it is the only drainage procedure that can drain the dependent portion of the stomach in the patient's upright position, and at the same time maintain gastroduodenal continuity. The basis for this advantage is that the incision for the Finney pyloroplasty is considerably longer than other pyloroplasties. It extends along the greater curve to the most dependent portion of the greater curve, which then is anastomosed to the side of the duodenal loop. Shorter incisions of other pyloroplasties do not reach the most dependent portion of the greater curve, and so may not provide adequate drainage in the upright position. Four technical details of the Finney pyloroplasty merit comment. First, the entire loop of the duodenum and head of the pancreas must be mobilized by the method of Kocher so that the pyloroplasty lies without
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tension and is not obstructed by torsion or angulation of the duodenum immediately distal to the pyloroplasty. Finney considered this mobilization of the duodenum to be the most important detail of his operation. Second, the length of the incision varies from patient to patient, and is a compromise between an incision long enough to drain the most dependent portion of the stomach and an incision short enough to avoid kinking the duodenum when the duodenum is swung over to approximate the stomach. Obviously the incision of the duodenum must be long enough to go beyond the ulcer in order to avoid obstruction at the ulcer. Third, the incision across the pylorus and onto the stomach must be close to the greater curve so that the posterior wall of the anastomosis does not prolapse into the stoma. Fourth, the technique of suturing must avoid excessive inversion so that obstruction does not occur from creating a diaphram of inverted tissue at the stoma. By fulfilling these requirements, the completed Finney pyloroplasty lies without any tension whatsoever and admits at least three fingertips with ease. In my experience, consistently successful results of adequate gastric drainage have been achieved with this technique. However, even the Finney pyloroplasty may not drain the most dependent portion of a large J-shaped or fishhook stomach. In these patients hemigastrectomy may prove to be the superior and necessary drainage procedure. In providing ample drainage with the wide stoma of the Finney pyloroplasty, dumping occurs in some patients. However the incidence and severity of dumping is significantly less than that following hemigastrectomy.
THE PLACE OF A VAGOTOMY THAT IS COMPLETE PLUS A DRAINAGE PROCEDURE THAT DRAINS
Experience in our Department has evolved through subtotal gastric resection, hemigastrectomy plus total vagotomy, hemigastrectomy plus selective vagotomy, and finally selective vagotomy plus pyloroplasty. In evaluating these operations from the standpoints of morbidity and mortality, gastrointestinal dysfunction and recurrent ulcer, our views are as follows. MORTALITY. We recognize that either subtotal resection or hemigastrectomy plus vagotomy may be performed without undue hazard upon patients of good operative risk undergoing elective operation. However, for patients with the emergencies of hemorrhage and perforation, and for patients of poor operative risk from other causes, resection with or without vagotomy is often a hazardous procedure. Vagotomy plus simple drainage, being an operation of much less magnitude, is preferable. GASTROINTESTINAL DYSFUNCTION. The incidence and severity of dumping, weight loss, anemia and so on with vagotomy plus pyloroplasty
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is considerably less than with either subtotal resection or hemigastrectomy plus vagotomy. In addition, it is our distinct clinical impression that the refinement of selective gastric vagotomy eliminates gastrointestinal dysfunction due to hepatic and celiac vagotomy. RECURRENT ULCER. With the advantages of the least mortality and the least gastrointestinal dysfunction, vagotomy plus pyloroplasty would clearly be the operation of choice were it not for the factor of recurrent ulcer. By eliminating the occurrence of incomplete vagotomy and gastric stasis with the techniques of vagotomy and pyloroplasty as previously described, no ulcer has recurred to date. However, personal experience is limited to only some 60 patients operated upon since 1963. Thus more time and more patients are obviously required for valid evaluation of Dragstedt's thesis that no ulcer recurs when both vagotomy and drainage are adequate. CONCLUSION. In order to take advantage of the least mortality and the least gastrointestinal dysfunction by vagotomy plus pyloroplasty, and at the same time eliminate recurrent ulcer from incomplete vagotomy and gastric stasis, my current operation of choice is selective gastric vagotomy plus Finney pyloroplasty.
REFERENCES 1. Baldwin, J. N., Albo, R., Jaffe, B. and Silen, W.: Metabolic effects of selective and total vagotomy. Surg. Gynec. & Obst. 120: 777-783 (April) 1965. 2. Dragstedt, L. R.: Section of the vagus nerves to the stomach and the treatment of duodenal ulcer. In Surgery of the Stomach and Duodenum (H. N. Harkins and L. Nyhus, Eds.). Boston, Little, Brown & Co., 1962, pp. 461-472. 3. Dragstedt, L. R., II: Vagotomy and gastroenterostomy or pyloroplasty: Present technique. S. CLIN. NORTH AMERICA 41: 23-26 (Feb.) 1961. 4. Eiseman, B.: What's New in Surgery: Gastrointestinal and biliary tract surgery. Surg. Gynec. & Obst. 120: 272-274 (Feb.) 1965. 5. Griffith, C. A.: Selective gastric vagotomy, Parts I and II. West. J. Surg. Obst. & Gynec. 70: 107-118, 175-180 (May-June and July-Aug.) 1962. 6. Griffith, C. A.: A new anatomic approach to the problem of incomplete vagotomy. S. CLIN. NORTH AMERICA 44: 1239-1252 (Oct.) 1964. 7. Kay, A. W.: Gastro-intestinal surgery and human physiology. J. Roy. CoIl. Surg. Edin. 7: 275-288 (July) 1962. 8. Moore, F. D.: Surgery in search of a rationale. Am. J. Surg. 105: 304-312 (March) 1963. 9. Murray, J. G.: The consequences of injury and disease of nervous tissue: Recent advances in knowledge. J. Roy. CoIl. Surg. Edin. 4: 199-217 (April) 1959. 10. Woodward, E. R.: Peptic ulceration of the stomach and duodenum. S. CLIN. NORTH AMERICA 39: 1195-1204 (Oct.) 1959. 11. Woodward, E. R. and Eisenberg, M. M.: Gastric physiology with reference to gastric and duodenal ulcers. S. CLIN. NORTH AMERICA 45: 327-343 (April) 1965. 1041 116th Street, N. E. Bellevue, Washington 98004
There is geographically scattered enthusiasm for selective vagotomy and pyloroplasty for duodenal ulcer. Reports are largely still at the anumerical testimonial stage and the majority of surgeons are watching the returns with caution. There is no evidence that this technically more tedious operation, with its threat of incomplete section, is superior to total vagectomy.-EIsEMAN (1965) It is to be hoped that the current interest in "selective vagotomy" will not provide a shelter for those surgeons who are unable to find and resect the right vagus.-MOORE (1963) Observation and study over a prolonged period of time will be necessary before one can determine whether or not selective vagotomy is followed by a lower incidence of such an infrequent sequela as diarrhea, and at the same time is not accompanied by an increased incidence of incomplete gastric vagotomy and recrudescent peptic ulcer.-WooDWARD AND EISENBERG (1965) Finally, although proponents of selective vagotomy have emphasized that the completeness of gastric denervation is more certain in the selective teehnique, enough doubt exists to prevent widespread use of this more difficult operation, regardless of the proposed advantages of this procedure.-BALDwIN, ALBO, JAFFE AND SILEN (1965)
In view of these criticisms against selective gastric vagotomy, the rebuttal will be stated at the outset. Selective gastric vagotomy poses two entirely separate and unrelated issues: (1) the safe and successful achievement of complete gastric vagotomy, and (2) the effects of hepatic and celiac vagotomy upon viscera other than the stomach. Of these two issues, the first is clearly the more important. Consequently, of primary concern are the criticisms that selective gastric vagotomy will prove technically too difficult and hazardous, and that it will increase the rate of incomplete gastric vagotomy. So far as I know, these criticisms come only from surgeons who have never evaluated the selective technique. In my experience, however, learnFrom the Department of Surgery, University of Washington School of Medicine, Seattie, Washington * Clinical Associate Professor of Surgery
367
368
CHARLES
A.
GRIFFITH
ing the anatomic principles of selective gastric vagotomy has been synonymous with learning the anatomic principles of complete gastric vagotomy. Furthermore, depending upon the specific operative circumstances, these anatomic principles may be applied in performing either selective gastric or total abdominal vagotomy. In either case, consistently successful results of complete gastric vagotomy have been achieved to date. This experience is by no means unique. In personal discussions with other surgeons who have also evaluated the selective technique in this country and in Great Britain, I have found unanimous agreement concerning the cardinal advantage of achieving complete gastric vagotomy. The advantage of the selective technique in assuring complete gastric vagotomy is best appreciated by comparing the selective technique with conventional techniques. The essential difference is that the selective technique applies constant anatomic landmarks, whereas conventional techniques do not.
CONVENTIONAL TECHNIQUES
The evolution of Dragstedt's operation has been summarized by Dragstedt II (1961). I shall therefore quote liberally from his account. When Dragstedt introduced vagotomy, the complications of gastric stasis were unknown. He performed only vagotomy per se, and chose the transthoracic approach because it "afforded an excellent exposure of the vagus nerves and made it possible to transect them before they had bifurcated extensively at the esophageal hiatus." When the need for gastric drainage became apparent, Dragstedt switched to the transabdominal approach in order to perform a concomitant drainage procedure. Transabdominal vagotomy was performed at the esophageal hiatus, and entailed an attempt to transect all vagal fibers as they emerged through the hiatus. However, the rate of incomplete vagotomy "rose substantially over what it had been when the transthoracic approach was used. This occurred because the vagus nerves branch widely just above the esophageal hiatus, and hence many small fibers were overlooked." Consequently, Dragstedt devised his present technique of transabdominal supradiaphragmatic vagotomy. From within the abdomen he incises the diaphragm just anterior to the hiatus, and through this counterincision of the diaphragm encircles the esophagus and vagi above the hiatus. "In this manner the vagus nerves can be identified and transected while they are still in two main trunks." The Problem of Incomplete Vagotomy
In evaluating Dragstedt's technique, Woodward (1959) concluded, "The major disadvantage is the unavoidably rather high incidence of in-
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complete vagotomy." The obvious difficulty is that the vagus nerves do not always exist as two main trunks at or above the hiatus. As described by Dragstedt (1962), "In about 50 per cent of cases, only two large trunks are seen; in the remaining 50 per cent, the anterior vagus nerve may be represented by two or more branches and in a small number the right or posterior vagus may be found as two or more trunks." Consequently, instead of conducting the operation with confidence that two and only two main trunks are present, we actually have no confidence whatsoever as to how many trunks there are or where they are. We transect only those we can find, and are left wondering if we have found them all. This, as I see it, is the real problem of incomplete vagotomy. In order to solve this problem-and it can be solved-we must first recognize the vagal system as a system independent of the diaphragm.
The Fallacy of the Diaphragm as the Anatomic Landmark From the left and right vagus nerves below the pulmonary plexus to the abdominal viscera, the vagal system consists of three constant components: (1) the esophageal plexus, which varies from a few large fibers in its simplest form to many small fibers in its most complex form; (2) two and only two main trunks, one anterior and one posterior; and (3) four truncal divisions, the hepatic, the celiac, and the anterior and posterior gastric divisions. This system has no anatomic relationship with the diaphragm, but descends through the hiatus in the form of anyone of its three constant components. The variable occurrence of the vagal system at the hiatus as the esophageal plexus or the trunks or the truncal divisions explains the variable occurrence of multiple nerves at the hiatus (Fig. 1). Two additional points pertain. First, full appreciation of the anatomic concept diagrammed in Figure 1 requires many dissections of the vagal system as a system in continuity from the thorax through the hiatus to the abdomen. It is an anatomic impossibility to recognize the vagal system as the esophageal plexus or the trunks or the truncal divisions in dissections confined to the hiatus or just above the hiatus. Second, and not readily apparent in Figure 1, the positions of the fibers of the esophageal plexus and the trunks and the truncal divisions are extremely variable at and above the hiatus. Not only may they lie in any of the 360 degrees around the circumference of the esophagus, but they may lie in variable positions away from the esophagus as well. In point of fact, above the hiatus some fibers may be closer to the aorta and mediastinal pleura than to the esophagus, and at the hiatus some fibers may be closer to the hiatal margins and aorta than to the esophagus.
The Unavoidable Pitfall At and Above the Hiatus Dragstedt has repeatedly emphasized the importance of a meticulous disseetion that lays bare the longitudinal muscle of the encircled esophagus in search of small nerves that may be lurking within the esophageal muscu-
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CHARLES
Right
nerve
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GRIFFITH
Left
nerve
A
Figure 1. The Vagal System and the Hiatus. A. The vagal system descends through the hiatus at A as the esophageal plexus, at B as the 2 trunks, and at C as the 4 truncal divisions.
B
Hepatic division
C
Celiac division
laris or fascia propria. However, despite this meticulous search (and despite complete transection of the esophagus in animals), incomplete vagotomy may still occur, and it occurs because the dissection does not guarantee identification and encirclement of all vagal fibers with the encircled esophagus. In dissections confined to the region of the hiatus, as is the case with either the conventional transabdominal technique or the transabdominal supradiaphragmatic technique, we are always confronted by an unknown component of the vagal system consisting of unknown numbers of nerves in unknown positions. Under these circumstances, in the attempt to encircle with the esophagus all vagal fibers that may be present, the encircling finger may blindly exclude one or more fibers, and thus completely displace them out of the surgical field. With emphasis upon finding and transecting all nerves in only the tissue that has been encircled with the esophagus, the nerves excluded from the encircled tissue are never looked for and never transected-at least not at the first operation. At the second operation however, performed by the technique to be described shortly, large intact nerves are found lying in virgin tissue well outside the operative scar around the esophagus. It is inconceivable that any experienced surgeon could overlook such large fibers, provided that he encircled these fibers with the esophagus and brought them into his surgical field at the first operation. The crux of the matter is this: no anatomic landmarks are available to prevent or recognize the error of excluding one or more vagal fibers when they are encircled at or above the hiatus. Thus a variable but certain occurrence of incomplete vagotomy is indeed unavoidable with conventional techniques.
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THE HEPATIC AND CELIAC VAGAL DIVISIONS: KEYS TO ENCIRCLEMENT OF ALL VAGAL FIBERS TO THE STOMACH
The hepatic and celiac divisions are the only two constant landmarks in the entire vagal system below the pulmonary plexus that may be applied to guarantee complete encirclement of all vagal fibers to the stomach. The third constant landmark is the angle of His-i.e., the crotch between the left aspect of the esophagus and the right aspect of the fundic dome of the stomach. By using these three landmarks, the operation starts not at the level of the hiatus but at a level well below it-namely, the gastric cardia. At this lower level of the cardia, and only at this lower level, do all gastric vagal fibers gather to innervate the stomach along its lesser curve. The hepatic vagal division is the landmark on the patient's right. It
can always be seen, even in obese patients, when the lesser omentum is stretched out by upward retraction of the left lobe of the liver and downward retraction of the stomach. The clearest view is obtained by visualizing the caudate lobe of the liver through the stretched-out fat-free transparent lesser omentum, and seeing the gray opaque hepatic fibers within the lesser omentum contrasted against the dark background of the caudate lobe. By incising the lesser omentum in its avascular area below the hepatic division and to the right of the gastric cardia, we can be certain of including all gastric vagal fibers on the right. No fibers reach the stomach to the right of this incision in the lesser omentum. * The landmark on the patient's left is the angle of His. By snipping the peritoneum over this angle, and introducing the finger into the crotch between the esophagus and gastric fundus, we can be certain of including all gastric vagal fibers on the left. No gastric fibers reach the fundus to the left of this incision in the peritoneum at the angle of His. By working through the incision in the lesser omentum below the hepatic vagal division on the right, and through the incision in the peritoneum at the angle of His on the left, we feel for the posterior landmarkthe posterior vagal trunk and its continuation as the celiac division. Although the position of the celiac division varies in the dorsal-ventral plane between the left gastric artery and right diaphragmatic crus, we can always identify it by palpation, particularly when it is stretched out and rendered tense by downward retraction of the stomach. The celiac division is always a large cord, readily felt and traced by palpation to its constant destination at the celiac plexus. By dissecting the finger through the tissue posterior to the celiac division, we encircle the celiac division with the esophagus. In
* Fibers of the hepatic vagal division go to the porta hepatis, where they enter the autonomic hepatic plexus. Dissections in some but not all cadavers demonstrate small fibers from the hepatic plexus descending with the right gastric vessels to the most distal antrum, pylorus and proximal duodenum. The function of these fibers is unknown. Their electric stimulation in dogs does not elicit any gastric contraction. When these fibers are left intact in patients with selective vagotomy and pyloroplasty, insulin hypoglycemia does not elicit free acid. Their function is most probably afferent sensory.
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Hepatic division
Celiac division
Figure 2. The Encirclement of All Vagal Fiber8 to the Stomach. As indicated by the arrow, all gastric vagal fibers may be encircled at once or, if preferred, in stages-first, the anterior fibers for anterior vagotomy, and second, the posterior fibers with the esophagus for posterior vagotomy.
this manner we may and perhaps often do exclude posteriorly some small celiac fibers to the bowel and pancreas, but we always include all fibers to the stomach. No gastric fibers lie in a position posterior to the celiac division (Fig. 2). By means of this technique, we gain positive anatomic assurance that the finger encircles all gastric vagal fibers with the esophagus. Furthermore, in my hands at least, encircling all gastric vagal fibers by this technique is just as easy and quick and safe as the conventional transabdominal technique at the hiatus, and is easier and quicker and safer than the transabdominal supradiaphragmatic technique above the hiatus. A soft rubber catheter or drain next replaces the encircling finger to maintain exposure. The operation now proceeds according to the choice of selective gastric or total abdominal vagotomy.
SELECTIVE GASTRIC VAGOTOMY OR TOTAL ABDOMINAL VAGOTOMY
Elsewhere in this symposium our Guest Editor, Dr. Ballinger, discusses the effects of hepatic and celiac vagotomy upon viscera other than the stomach. I believe these effects are important, particularly when both hepatic and celiac vagotomy are complete. As incomplete gastric vagotomy may occur, so may incomplete hepatic and incomplete celiac vagotomy occur. Unfortunately, we have no tests for completeness of hepatic and celiac vagotomy, and therefore are more or less thwarted in our efforts to study this problem. Although the evidence is still controversial, I believe that hepatic and celiac vagotomy is neither necessary nor desirable, and therefore perform selective gastric vagotomy whenever operative circumstances permit.
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Anatomic and technical details of selective vagotomy have been previously published (Griffith, 1962, 1964). Rather than repeat these details I shall discuss the issue of technical difficulty. Selective gastric vagotomy requires a more extensive and meticulous dissection than total abdominal vagotomy. In my initial experience I therefore selected thin patients undergoing elective operation, and did not encounter any particular difficulties or hazards. As experience increased I gradually extended the operation to include more obese patients, and have continued to do so. However, total abdominal vagotomy is often the wiser choice for some obese or poor-risk patients.
Anterior Vagotomy Anterior selective vagotomy entails transection of all tissue anterior to the esophagus-from the incision in the lesser omentum beneath the hepatic division on the right, to the incision in the peritoneum at the angle of His on the left. This tissue contains all anterior gastric vagal fibers plus small branches of the esophageal vessels, and therefore is transected between clamps. This dissection lays bare the entire anterior surface of the esophagus. Anterior selective vagotomy is usually technically easy. Three circumstances may occasionally pose difficulties. The first is adhesions plastering the stomach to the under surface of the liver. The second is the occurrence (10 to 15 per cent) of a large accessory or replacing left hepatic artery from the left gastric artery. When present, this aberrant left hepatic artery runs just below and very close to the hepatic vagal division in the lesser omentum to the porta hepatis. Third, in some patients the fibers of the hepatic division arise quite low, just above the cardia, and care must be taken to preserve them. Although they may be preserved, total anterior vagotomy is easier because the tissue anterior to the esophagus may be transected without regard for low lying hepatic fibers.
Posterior Vagotomy The performance of posterior selective vagotomy requires positive identification of the posterior trunk and celiac division. This requirement is all-important, for it eliminates the most common error resulting in incomplete vagotomy-namely, missing the posterior trunk. As previously described, the posterior trunk and celiac division may be identified by palpation when the vagal fibers are initially encircled with the esophagus. However, this maneuver becomes easy only by doing it. If not initially identified and encircled, the posterior trunk and celiac division must be located after anterior vagotomy is completed (Legend, Fig. 2). Location of the posterior trunk and celiac division in the surgical field following anterior selective vagotomy is much easier than in the more limited field following anterior total vagotomy. Posterior selective vagotomy entails transection of all tissue between
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the posterior vagal trunk and celiac division on the right, and the esophagus and proximal lesser curve of the stomach on the left. Because some posterior gastric vagal fibers reach the stomach via the left gastric artery in some patients (Jackson, 1948), the left gastric artery must be transected and ligated adjacent the lesser curve. For surgeons experienced in gastric resection, posterior selective vagotomy is usually not particularly hazardous or difficult. However, as with gastric resection we must protect an aberrant left hepatic artery. Posterior selective vagotomy obviously requires a more extensive dissection than posterior total vagotomy, particularly in the obese patient. Dissection of the Esophagus
Selective gastric vagotomy essentially entails transection of all tissue that has been encircled except the hepatic and celiac divisions and the esophagus. Total abdominal vagotomy leaves only the esophagus. Although not diagrammed in Figure 1, small gastric vagal fibers may occasionally arise not from their respective truncal divisions but independently from the trunks or esophageal plexus above. These small independent gastric fibers usually lie in the esophageal fascia propria, and are transected by a final dissection that lays bare the longitudinal muscle of the esophagus. Fibers occasionally felt within the esophageal muscle are esophageal fibers, I believe, and therefore need not be transected by dissections that violate the integrity of the esophageal muscle.
ADEQUATE AND INADEQUATE INCOMPLETE GASTRIC VAGOTOMY
Although the rates of recurrent ulcer and incomplete vagotomy vary from series to series, the rate of incomplete vagotomy is always higher than the rate of recurrent ulcer. In studying patients with incomplete vagotomy by means of the insulin and histamine tests, the positive responses of gastric acid vary in degree from weakly to strongly positive. Patients with strongly positive responses are the ones who develop recurrent ulcer, and therefore their incomplete vagotomy is inadequate. Patients with weakly positive responses may not develop recurrent ulcer, and therefore their incomplete vagotomy is adequate. This discrepancy of different physiologic degrees of incomplete vagotomy is most probably due to different anatomic types of incomplete vagotomy. Vagotomy does not obey the all-or-none phenomenon. Failure to transect a large fiber of the esophageal plexus or an entire trunk or an entire gastric division is quite different from failure to transect a small independent gastric fiber supplying only a small portion of stomach. Furthermore, the amount of vagal reinnervation by sprouting (Murray, 1959) most probably is influenced by the anatomic type of incomplete vagotomy. In Dragstedt's recent experience (1962), he reports a 2 per cent rate of
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inadequate incomplete vagotomy. This exceedingly low rate is in the hands of the master, however, and in less expert hands the rate is notoriously higher. I am convinced that this high rate of inadequate incomplete vagotomy may be significantly lowered by encircling all fibers to the stomach as previously described, because in doing so there is a minimal or even no chance of missing a large branch of the esophageal plexus or a large trunk or an entire gastric division.
THE COMPLEMENTARY PROCEDURE
Exclusive of ulcerogenic pancreatic tumor, Dragstedt propounds that the ulcer will heal, and remain healed, if (1) gastric vagotomy is adequate, and (2) gastric drainage is adequate. The only real challenge to this thesis is that by Kay (1962), who proposes that a few patients with adequate vagotomy and adequate drainage will develop recurrent ulcer due to unusual potential of the retained antrum and parietal cell mass. Only time will prove or disprove the validity of Kay's proposal. At the present time, all other available experimental and clinical evidence indicates that Dragstedt's thesis is standing the test of time and is correct. Dragstedt (1962) performs Weinberg's modification of the HeinekeMikulicz pyloroplasty or, if pyloroplasty appears hazardous, gastrojejunostomy in the antrum 4 to 6 cm. from the pylorus, and with a stoma not greater than 1.5 cm. (to minimize dumping). These two drainage procedures are not infallible in preventing gastric stasis. In point of fact, in Dragstedt's current experience gastric stasis is a more common cause of recurrent ulcer than incomplete vagotomy. Drainage of the vagotomized stomach by pyloroplasty is not only influenced by the size of the stoma in relation to the size of the duodenal lumen, but is also influenced by the position of the stoma in relation to the most dependent portion of the stomach as well. Although there is as yet no clear-cut clinical evidence indicating the superiority of one pyloroplasty over all others, the Finney pyloroplasty seems superior,. because when performed as described by Finney, it is the only drainage procedure that can drain the dependent portion of the stomach in the patient's upright position, and at the same time maintain gastroduodenal continuity. The basis for this advantage is that the incision for the Finney pyloroplasty is considerably longer than other pyloroplasties. It extends along the greater curve to the most dependent portion of the greater curve, which then is anastomosed to the side of the duodenal loop. Shorter incisions of other pyloroplasties do not reach the most dependent portion of the greater curve, and so may not provide adequate drainage in the upright position. Four technical details of the Finney pyloroplasty merit comment. First, the entire loop of the duodenum and head of the pancreas must be mobilized by the method of Kocher so that the pyloroplasty lies without
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tension and is not obstructed by torsion or angulation of the duodenum immediately distal to the pyloroplasty. Finney considered this mobilization of the duodenum to be the most important detail of his operation. Second, the length of the incision varies from patient to patient, and is a compromise between an incision long enough to drain the most dependent portion of the stomach and an incision short enough to avoid kinking the duodenum when the duodenum is swung over to approximate the stomach. Obviously the incision of the duodenum must be long enough to go beyond the ulcer in order to avoid obstruction at the ulcer. Third, the incision across the pylorus and onto the stomach must be close to the greater curve so that the posterior wall of the anastomosis does not prolapse into the stoma. Fourth, the technique of suturing must avoid excessive inversion so that obstruction does not occur from creating a diaphram of inverted tissue at the stoma. By fulfilling these requirements, the completed Finney pyloroplasty lies without any tension whatsoever and admits at least three fingertips with ease. In my experience, consistently successful results of adequate gastric drainage have been achieved with this technique. However, even the Finney pyloroplasty may not drain the most dependent portion of a large J-shaped or fishhook stomach. In these patients hemigastrectomy may prove to be the superior and necessary drainage procedure. In providing ample drainage with the wide stoma of the Finney pyloroplasty, dumping occurs in some patients. However the incidence and severity of dumping is significantly less than that following hemigastrectomy.
THE PLACE OF A VAGOTOMY THAT IS COMPLETE PLUS A DRAINAGE PROCEDURE THAT DRAINS
Experience in our Department has evolved through subtotal gastric resection, hemigastrectomy plus total vagotomy, hemigastrectomy plus selective vagotomy, and finally selective vagotomy plus pyloroplasty. In evaluating these operations from the standpoints of morbidity and mortality, gastrointestinal dysfunction and recurrent ulcer, our views are as follows. MORTALITY. We recognize that either subtotal resection or hemigastrectomy plus vagotomy may be performed without undue hazard upon patients of good operative risk undergoing elective operation. However, for patients with the emergencies of hemorrhage and perforation, and for patients of poor operative risk from other causes, resection with or without vagotomy is often a hazardous procedure. Vagotomy plus simple drainage, being an operation of much less magnitude, is preferable. GASTROINTESTINAL DYSFUNCTION. The incidence and severity of dumping, weight loss, anemia and so on with vagotomy plus pyloroplasty
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is considerably less than with either subtotal resection or hemigastrectomy plus vagotomy. In addition, it is our distinct clinical impression that the refinement of selective gastric vagotomy eliminates gastrointestinal dysfunction due to hepatic and celiac vagotomy. RECURRENT ULCER. With the advantages of the least mortality and the least gastrointestinal dysfunction, vagotomy plus pyloroplasty would clearly be the operation of choice were it not for the factor of recurrent ulcer. By eliminating the occurrence of incomplete vagotomy and gastric stasis with the techniques of vagotomy and pyloroplasty as previously described, no ulcer has recurred to date. However, personal experience is limited to only some 60 patients operated upon since 1963. Thus more time and more patients are obviously required for valid evaluation of Dragstedt's thesis that no ulcer recurs when both vagotomy and drainage are adequate. CONCLUSION. In order to take advantage of the least mortality and the least gastrointestinal dysfunction by vagotomy plus pyloroplasty, and at the same time eliminate recurrent ulcer from incomplete vagotomy and gastric stasis, my current operation of choice is selective gastric vagotomy plus Finney pyloroplasty.
REFERENCES 1. Baldwin, J. N., Albo, R., Jaffe, B. and Silen, W.: Metabolic effects of selective and total vagotomy. Surg. Gynec. & Obst. 120: 777-783 (April) 1965. 2. Dragstedt, L. R.: Section of the vagus nerves to the stomach and the treatment of duodenal ulcer. In Surgery of the Stomach and Duodenum (H. N. Harkins and L. Nyhus, Eds.). Boston, Little, Brown & Co., 1962, pp. 461-472. 3. Dragstedt, L. R., II: Vagotomy and gastroenterostomy or pyloroplasty: Present technique. S. CLIN. NORTH AMERICA 41: 23-26 (Feb.) 1961. 4. Eiseman, B.: What's New in Surgery: Gastrointestinal and biliary tract surgery. Surg. Gynec. & Obst. 120: 272-274 (Feb.) 1965. 5. Griffith, C. A.: Selective gastric vagotomy, Parts I and II. West. J. Surg. Obst. & Gynec. 70: 107-118, 175-180 (May-June and July-Aug.) 1962. 6. Griffith, C. A.: A new anatomic approach to the problem of incomplete vagotomy. S. CLIN. NORTH AMERICA 44: 1239-1252 (Oct.) 1964. 7. Kay, A. W.: Gastro-intestinal surgery and human physiology. J. Roy. CoIl. Surg. Edin. 7: 275-288 (July) 1962. 8. Moore, F. D.: Surgery in search of a rationale. Am. J. Surg. 105: 304-312 (March) 1963. 9. Murray, J. G.: The consequences of injury and disease of nervous tissue: Recent advances in knowledge. J. Roy. CoIl. Surg. Edin. 4: 199-217 (April) 1959. 10. Woodward, E. R.: Peptic ulceration of the stomach and duodenum. S. CLIN. NORTH AMERICA 39: 1195-1204 (Oct.) 1959. 11. Woodward, E. R. and Eisenberg, M. M.: Gastric physiology with reference to gastric and duodenal ulcers. S. CLIN. NORTH AMERICA 45: 327-343 (April) 1965. 1041 116th Street, N. E. Bellevue, Washington 98004