An Active Diagnostic Approach to Blunt Abdominal Trauma

An Active Diagnostic Approach to Blunt Abdominal Trauma ROBERT J. FREEARK, M.D., F.A.C.S.* LEON LOVE, M.D., F.A.C.R.** ROBERT J. BAKER, M.D., F.A.C.S.***

Recent statistics suggest that over two million Americans will be injured in automobile accidents this year. In addition, civilian and military violence is an ever-increasing individual hazard. A significant proportion of the more serious injuries will involve the abdominal viscera; the responsibility for prompt diagnosis may rest with physicians who have limited experience with such emergencies. Newer diagnostic techniques can facilitate evaluation of the injured patient, especially when multiple injuries are encountered in a given patient. By placing the recognition of abdominal injury on a more objective basis than that provided by history and physical examination, and by interjecting additional special skills into the earfy management of accident victims, the likelihood of diagnostic omission is lessened considerably. This report is concerned with the indications for and application of several diagnostic maneuvers designed to facilitate the recognition of abdominal injuries. These techniques have been used in the management of a large number and variety of patients seen in the emergency room and on the wards of a large metropolitan hospital. It has become apparent that they constitute a valuable addition to the armamentarium of those charged with the care of the injured. From the Departments of Surgery and l;tadiology, Cook County Hospital, Northwestern University Medical School, The University of Illinois at the Medical Center, and the Hektoen Institute for Medical Research of Cook County Hospital, Chicago, Illinois *Professor of Surgery, Northwestern University Medical School; Director of Surgery, Cook County Hospital **Clinical Professor of Radiology, Chicago Medical School; Director of Diagnostic Radiology, Cook County Hospital ***AssoCiate Professor of Surgery, University of Illinois College of Medicine; Associate Director of Surgery, Cook County Hospital

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Table 1. Special Techniques Used in the Diagnosis of Abdominal Injury TECHNIQUE ABDOMINAL pARACENTESIS

SERUM AND URINE AMYLASE

FINDING

INTERPRETATION

a. Dry tap b. Nonclotting blood c. Bile stained fluid with manyWBC's d. Serous fluid with few WBC's

None Serious injury

a. Increased Early Late b. Normal (Early after injury)

PNEUMOPERITONEUM a. Air enters subphrenic spaces to outline normal diaphragm, liver and spleen b. Air fails to enter subdiaphragmatic space on one or both sides AORTOGRAPHY

a. Artery occluded b. Artery displaced c. Dye extravasated d. Organ displaced e. Organ contour disrupted f. Early venous filling (A-V fistula)

a. Dye extravasated GASTROINTESTINAL CONTRAST STUDIES b. Obstruction (duodenum) c. Coiled spring appearance d. Displacement

Probably positive

ORGAN INJURY SUSPECTED CoiTelate clinically Spleen, liver, mesenteric vessel Rupture of small intestine, biliary tract

Probably negative

CoiTelate clinically

Serious injury

Disruption of pancreas or duodenum Pancreatic pseudocyst CoiTelate clinically

Significant Pancreatic injury unlikely Negative

None detected

Positive

CoiTelate clinically (rule out previous upper abd01ninal surgery)

Traumatic thrombosis or disruption Adjacent hemorrhage, mass Organ or vessel disrupted Hematoma, mass adjacent Fracture or subcapsular hematoma Organ fractures

CoiTelate clinically

Leak Hematoma

Ruptured stomach, duodenum Duodenum

Hematoma

Duodenum

Retroperitoneal hematoma, pancreatic inflammation

Pancreas, kidney adrenal

CoiTelate clinically CoiTelate clinically CoiTelate clinically CoiTelate clinically Spleen, kidney

Trauma involving the abdominal viscera usually becomes manifest through the development of peritoneal irritation, or the signs of acute blood loss. When no other injuries exist in the alert, responsive patient, thorough and repeated examinations of the abdomen and the use of

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routine laboratory and radiologic studies should insure prompt recognition of most injuries to the solid abdominal viscera, intestine, and urinary tract. However, three additional factors may greatly complicate the situation, First, the presence of coexisting head injury or alcoholic intoxication may mask the usual clinical signs of peritonitis. Second, when the patient has sustained multiple injuries, particularly those involving the chest and bony pelvis, physical findings closely simulating intra-abdominal injuries may appear. Also, evidence of acute blood loss coexisting with the associated injuries may be confusing, and uncertainty can develop as to the source of bleeding. Finally, an increasing incidence of retroperitoneal organ injury has been recognized. These wounds are capable of producing a considerably subtler spectrum of symptoms and signs than those involving the intraperitoneal viscera. Subacute, or even chronic, conditions may occur and, in the case of injuries to organs such as the duodenum, pancreas, or adrenals, the findings of peritoneal irritation or blood loss are often minimal or absent. Consideration of these factors, and our past experience with the disastrous consequence of delay in the diagnosis and treatment of abdominal trauma, has led us to pursue a far more active diagnostic approach to the patient with abdominal injuries. Outlined in Table 1 are the findings in certain studies which we have found to be particularly useful. The choice of diagnostic study depends, of course, on the condition of the patient and the nature of the injury. The techniques currently employed and the significance of findings which they demonstrate will be discussed.

SERUM AND URINE AMYLASE DETERMINATIONS Elevation of the serum amylase may occur in patients with injury or disease of the pancreas and duodenum. Increase in the urinary level of this enzyme has been noted to persist for longer periods, and is considered more reliable, than blood level as an index of pancreatic acinar or ductal disruption. 8 Since both pancreas and duodenum are largely retroperitoneal, and difficult to evaluate by palpation or routine x-ray studies, early diagnosis is often possible by detecting abnormal amylase levels in the blood and urine. Serum lipase seems to have no advantage over amylase in terms of sensitivity or persistence of elevation, and is not used clinically in most hospitals. As a general rule, laparotomy is recommended for those patients with significant elevations of blood or urine amylase following trauma. Our experience suggests that the incidence of duodenal injury and the frequency of major disruptions of the pancreatic ductal system are sound and sufficient reasons for recommending operative exploration of the duodenum and pancreas in patients with elevated blood and/or urine levels after trauma. 5 The method by which blood or urine amylase levels are measured is far less important than knowledge of the normal values for this determination. A single sample of either blood or urine may reflect a significant elevation, but the two-hour or 24-hour urinary excretion of this

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enzyme is a more reliable method for establishing abnormalities. One or all of these urinary excretion studies should be performed in every patient with blunt abdominal trauma and the results carefully correlated with the clinical progress of the patients. We have encountered a number of patients with complete transections of the pancreas or duodenum in whom the vital signs remained stable for several days, and the abdominal findings were not suggestive of significant abdominal injury. Elevations of the blood or urine amylase levels provided objective evidence of the existence of pancreatic or peripancreatic injury and led to further diagnostic study or operative intervention. Finally, it is worth emphasizing that serial determinations of these enzymes following pancreatic trauma or surgery are occasionally helpful in the detection of complications. Persistent elevation over a period of several days to weeks suggests the development of a pancreatic pseudocyst, and possibly fistula or abscess formation.

ABDOMINAL PARACENTESIS The cautious insertion of a needle or catheter into the peritoneal cavity of those patients suspected of having sustained intra-abdominal injury has proved a safe and reliable method for the detection of injuries to the abdominal viscera. While the number and sites of insertion, type of instrument used, and timing vary in published reports, most observers record an overall accuracy of close to 90 per cent. 17 Since serious injury to the underlying intestine by the needle is rarely observed, the major reservation concerning this diagnostic technique has to do with the tendency to assume that a negative, or "dry," tap precludes the possibility of serious abdominal injury. Realization of the fact that it is sometimes impossible to aspirate free blood although hemoperitoneum is present, and that many of the most urgent injuries involve retroperitoneal organs such as the duodenum or pancreas, should serve to reinforce the truism, "Negative means nothing." If aspiration returns blood-stained fluid or nonclotting blood from the peritoneal cavity, major visceral damage requiring laparotomy has probably occurred; further observation is dangerous, and operation should be undertaken without delay. In the performance of diagnostic paracentesis, it is preferable to place the patient in the lateral decubitus position, that is, lying on the side of presumed injury. If there is no indication of its location, we prefer the left side to be down. Following careful cleansing of the skin, a short-bevel 18-gauge needle attached to a 20-ml. syringe is inserted at the level of the umbilicus just lateral to the outer border of the rectus sheath on the dependent side of the abdomen. The patient experiences slight discomfort as the needle penetrates the skin. The examiner then becomes aware of the resistance of the aponeurosis of the external oblique and other abdominal muscles.)Advancing the needle farther results in a momentary, sharp pain as it penetrates the parietal peritoneum. This is accompanied by a sensation of "give" as there is a lessened resistance to further progress of the needle. Once the needle has clearly entered the abdominal cavity, aspiration

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is begun and any return noted in the syringe. If no return is observed, the needle is slowly withdrawn, again with constant aspiration. Slow withdrawal is extremely important for, in many instances, only a thin layer of free peritoneal fluid or blood exists between viscera and abdominal wall, and, if the layer is traversed too rapidly, it will not enter the syringe. Any nonbloody material aspirated must be further evaluated as to whether it was obtained from the free peritoneal cavity or from the occasional penetration of a loop of intestine. Microscopic examination of the aspirate will yield epithelial cells and bacteria if the material was obtained from the intestinal lumen, whereas significant peritoneal fluid is loaded with polymorphonuclear leukocytes. Concem for the possibility of damage to otherwise normal viscera by needle puncture appears unwarranted. We have aspirated intestinal contents on occasion, and have seen no evidence to suggest that the patient has been harmed by penetration of normal viscera. N evertheless, we caution against paracentesis in patients with significant gaseous abdominal distention because of the slight risk of leak from a needle hole in markedly dilated intestine. The aspiration of blood which clots suggests that the needle has entered a vessel in the abdominal wall or mesentery, an event of little consequence. Bloody fluid which fails to clot is characteristic of hemoperitoneum arising from damage to the liver, spleen, mesenteric vessels or, occasionally, large retroperitoneal hematomas which escape into the free peritoneal cavity. One additional matter for concern centers around the possibility that small amounts of air may enter the peritoneal cavity during the needle paracentesis. This will result in radiologic evidence of free air, iatrogenic in origin. 16 For this reason, it is desirable to perform paracentesis after routine roentgenographic studies are completed so that the finding of pneumoperitoneum cannot be misinterpreted. The routine aspiration of all four quadrants of the abdomen has been recommended, but has not appeared to significantly increase the reliability of the technique in our hands. Similarly, the insertion of a polyethylene tube into the abdominal cavity with instillation of 1000 ml. of saline,t 4 and subsequent aspiration for chemical and microscopic study, has seemed to us to complicate needlessly the performance of an otherwise safe, simple, and reliable procedure.

VISCERAL AORTOGRAPHY Application of angiographic techniques to the study of nonpenetrating abdominal trauma has proved of real diagnostic value. Earlier reports 1 • 2 • 3 • 4 • 11 • 12 • 13 emphasized those instances in which selective injection of contrast material into the celiac, superior mesenteric or renal arteries was helpful in detection or evaluation of injuries to the spleen, liver, or kidney. In most instances, however, such injuries were strongly suspected on clinical grounds. The angiographic study proved useful in confirming the clinical impression, assessing the magnitude of injury, or establishing an appropriate course of action. In 1966, we undertook an evaluation of abdominal aortography in

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Figure I. ormal abdominal aorto1'1•, 2'1• and 5 seconds after rapid 111Jecuon of contrast material. A, ote filJing of all major visceral and parietal branches (early arterial phase). B, Dye enters smaller branches to organs such as spleen, lddney, and liver (late arterial phase). C, Opacification of organs allowmg assessment of contour, location, and dye excretion (nephrogram, splenogram phase). gram~

the detection of injuries resulting from blunt trauma. 6 Whenever feasible, patients suspected of abdominal injury were studied shortly after admission to the hospital, always following the completion of routine examination and laboratory study. Percutaneous retrograde catheterization via the femoral artery was carried out, utilizing the Seldinger technique. 15 The catheter tip was positioned fluoroscopically at the upper level of the 12th thoracic vertebrae and 50 to 75 mi. of 66.8 per cent sodium iodothalamate (Conray-400) was injected rapidly at a rate of 30 cc. per second using the Elema-Schonander casette changer. Serial films were obtained at periods of 4 per second for the next 3 seconds and 1 per second thereafter for a total of 10 seconds after injection. In contrast to the time-consuming and considerably more difficult catheterization of a specific vessel ("selective" technique), the "flush" technique is rapid, simple and provides visualization of the entire abdominal aorta and its branches (Fig. 1). By obtaining serial films following injection, a detailed study of the vessels supplying the ab-

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Figure 2. Angiographic diagnosis of splenic rupture (three patients). A, Spleen displaced (perisplenic hematoma). B, Dye extravasated (intrasplenic hemorrhage). C, Early venous filling (traumatic A- V shunt).

Figure 3. Displacement of gastroduodenal artery due to large intramural hematoma of duodenum.

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Figure 4. Traumatic arteriovenous fistula resulting from blunt trauma to kidney with hematuria. A, Arterial phase. B, Venous phase.

dominal parietes, as well as organs such as the spleen and kidney, is possible. During the later phases following injection, dense opacification of these viscera occurs, permitting an estimation of their size, location, and function. At times, the venous return from the respective organs can be noted. Finally, in the case of the kidney, the contrast material may ultimately be followed into the renal pelvis, ureters, and bladder as excretory pyelography and cystography; the films yielded are identical in quality to those obtained by the intravenous route. Aortographic evidence of major visceral damage varies with the type of injury, as well as the organ involved (Table 2; Figs. 2, 3, 4, and 5). In some instances, the findings are merely suggestive. More frequently,

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Figure 5. Postoperative aortograrn showing complete occlusion of right renal artery missed at operation for rupture of the liver. (Kidney nonsalvageable.)

• unequivocal evidence of significant organ damage, and the need for surgical treatment, are established. Indications for aortographic study (Table 3) have been extended as our experience with this technique has increased. The studies are performed by our resident staff day or night. Although operation has

Table 2. Angiographic Diagnosis of Blunt Abdominal Trauma PATIENTS STUDIED

73

Acute (first 48 hours) Late (after 48 hours)

43 30

INJURIES OBSERVED (Patients)

29

Ruptured Spleen Positive* (extravasation, AV fistula) Suggestive (displacement) Negative (no abnormality noted)

Fractured Kidney Positive (one renal artery occlusion)

Pancreatic Disruption Suspicious (displacement of pancreatoduodenal or splenic artery) Negative

Duodenal Injuries Suspicious (pancreatoduodenal artery displacements by intramural hematoma) Negative

Hepatic Injuries Suggestive (hepatic artery occlusion) Negative No INJURIES DEMONSTRATED (Aortography or Clinical)

16 8 7 1

8 8 4 2 2 2

1 1 4 1 3 54

*One additional patient was considered to have a positive angiogram for rupture of the spleen, but no abnormality was found at operation.

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Table 3. Indications for Aortography in Blunt Abdominal Trauma Possible splenic injury Multiple-injury patient (acute or delayed rupture) Stuporous or comatose patient Traumatic hematuria with suspected injury Possible retroperitoneal injury Post-traumatic masses Unexplained blood loss

been decided upon, we have found a preoperative angiogram of distinct benefit to the surgeon, as it may alert him to findings within the abdomen which might easily be overlooked. For example, decisions regarding the exploration of retroperitoneal hematomas, and whether to open the perirenal fascia in cases of kidney injury, may be expeditiously resolved by a review of the vascular pattern in the abdominal parietes, or in the renal parenchyma. The angiogram has, in effect, provided a "road map" by which the exploring surgeon may greatly increase his efficiency and improve his results. At the present time, aortography constitutes the single most reliable method for the definitive diagnosis of acute or delayed rupture of the spleen, and for the overall evaluation of traumatic hematuria. In the latter instance, both structure and function can be assessed. In addition to the follow-through pyelographic and cystographic study, it provides detailed information about the renal vasculature, and can detect thrombosis, false aneurysm, arteriovenous fistula, and preexisting vascular abnormalities. Definitive management of the injured kidney at the time of the operation is facilitated by adequate visualization of the vasculature, avoiding the vagaries of assessing such lesions by inspection and palpation alone. 9 Our experiences with angiography in abdominal trauma are summarized in Table 2. Over 70 visceral aortograms have been performed in patients with acute injuries without a major complication occurring either at the site of femoral arterial puncture or from the injection of the contrast material. While both false positive and false negative examinations have been observed, they are infrequent and occurred early in our utilization of the technique. The information obtained has more than justified any delay in operative intervention that the procedure entails, or the inconvenience or discomfort to the patient.

GASTROINTESTINAL CONTRAST STUDIES Contrast studies of the gastrointestinal tract have proved of value in many patients with abdominal injuries. This is particularly true of injuries to the pancreas and duodenum where physical findings are often minimal and are readily obscured by associated injuries. Such studies have facilitated detection of disruptions of the gastroduodenal segment, intramural hematomas of the wall of the duodenum and large retroperitoneal hematomas adjacent to these areas. 7 Injuries confined to the pancreas are often suggested by pressure defects in the duodenum, disturbed peristalsis, altered mucosal pattern, and by later development of space-occupying pseudocysts which displace stomach, duodenum, or colon in a characteristic manner.

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The choice of the contrast material employed for such studies is somewhat controversial. Where disruptions of the gastrointestinal tract may have occurred, the use of a water-soluble radiopaque material is usually recommended because of its nontoxic qualities, ready absorbability, and the possibility that extravasation into the peritoneal cavity or retroperitoneal space may occur. In practice, however, the gross disruption is usually recognized on clinical grounds and contrast studies are unnecessary. If the diagnosis is obscure, and the leak small, hence, clinically silent, the improved quality of studies performed with barium suspensions far outweighs theoretical considerations as to their toxicity or removal. Barium sulfate is an inert salt and intraperitoneal barium is of consequence only as it indicates spill of intestinal content into the peritoneal cavity. Upper gastrointestinal studies are recommended in the investigation of patients with persistent or unexplained pain or vomiting following abdominal trauma. They are performed early in the course of hospitalization in instances in which physical examination and other laboratory tests have failed to establish a clear-cut indication for surgical treatment. They can be quite useful in patients with blunt trauma who have slight or borderline elevations of the serum and urine amylase, questionable evidence of retroperitoneal air, obliteration of one psoas shadow, or occult blood loss suggesting retroperitoneal hematoma. When patients are transferred from other hospitals for observation, diagnosis, or treatment, and several days have elapsed since injury, contrast x-ray can be an invaluable means of assessing abdominal findings which were not observed during the immediate post-injury period. Obstructing hematomas in the wall of the duodenum, pancreatic pseudocysts, traumatic diaphragmatic hernias, and gastric displacement from hematomas about a ruptured spleen have been identified by this method in patients whose injury occurred one week to many months earlier. Finally, the possibility that trauma may exist with some incidental pre-existing abnormality or disease cannot be overlooked. We have recently encountered patients with cholelithiasis and empyema of the gallbladder, acute appendicitis, ruptured tubo-ovarian abscesses, and gastrointestinal neoplasms, who related the onset of their symptoms to a specific abdominal injury. In some instances, these lesions can be found by appropriate x-ray examination.

DIAGNOSTIC PNEUMOPERITONEUM The deliberate injection of air or carbon dioxide into the free peritoneal cavity has been found useful in establishing the precise location of the diaphragm and the elucidation of pathologic conditions occurring immediately above or below it. This technique has proved valuable in the diagnosis of delayed rupture of the spleen, traumatic diaphragmatic hernia, and injuries and anomalies of the liver. 10 Perhaps the greatest advantage is in the evaluation of pleural effusions following abdominal trauma or surgery, when the location of the diaphragm is obscured by collections of fluid.

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Figure 6. Diagnostic pneumoperitoneum in patient found to have a delayed rupture of the spleen and pleural effusion. Note the failure of gas to enter the left subphrenic space. (Abdominal paracentesis was negative.)

When routine roentgenography and other contrast studies have failed to confirm or reliably exclude a peridiaphragmatic process, diagnostic pneumoperitoneum is indicated. With the patient on the x-ray table, a needle is inserted under local anesthesia in the lower abdominal midline after careful preparation of the skin and emptying the bladder. Every effort is made to enter the free peritoneal cavity without entering loops of intestine, as demonstrated by the inability to aspirate intestinal content, blood or air, and the absence of discomfort upon first injecting the air. Ordinarily, 500 to 1000 ml. of room air is injected using a 50- or 100-cc. syringe and a three-way stopcock. With both the needle and patient stabilized, 500 to 1000 cc. of air is introduced over a period of five minutes, and the needle withdrawn. With careful upright positioning of the patient under fluoroscopy, the gas will rise to the superior levels of the abdomen and provide fine contrast visualization of the surface of the diaphragm, as well as the outline of the liver and spleen. Films in the upright anteroposterior, upright lateral, and supine decubitus positions are obtained. Failure of the air to enter the subphrenic spaces (Fig. 6) suggests their obliteration by an abnormal collection, such as blood, pus, or fibrinous exudate. It is important to emphasize that air embolism has occurred during the performance of diagnostic and therapeutic pneumoperitoneum. In addition, the introduction of a gas into the peritoneal cavity will occasion slight to moderate discomfort as a result of diaphragmatic irritation. The pain is usually referred to the shoulder or neck, and lasts for several hours. Also of importance is an awareness of the fact that the gaseous material will often remain in the peritoneal cavity for several days, thereby negating the value of demonstration of intra-abdominal air as a sign of a spontaneous p~thologic process. In spite of these limitations, the procedure has distinct merit in the evaluation of certain patients suspected of having major intra-abdominal injuries or disease.

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SUMMARY AND CONCLUSION As the frequency and complexity of trauma increase, more vigorous and sophisticated diagnostic efforts are required. Procedures which objectively confirm the existence of serious injury facilitate treatment and permit a planned operative approach. When abdominal injury is suspected but confirmation using routine methods is lacking, the employment of special diagnostic techniques has proved of great benefit. Diagnostic abdominal paracentesis and serum and urine amylase determinations are easily performed, but require thoughtful interpretation. Diagnostic pneumoperitoneum and contrast studies of the upper gastrointestinal tract are readily avlrllable in most hospitals and are useful in the investigation of special problems. Visceral aortography requires special radiological facilities, but offers great promise in the diagnosis of a variety of injuries to the spleen, kidney, and retroperitoneal organs.

REFERENCES 1. Baum, S., Nusbaum, M., Blakemore, W. S., and Finkelstein, A. K.: The preoperative radiographic demonstration of intra-abdominal bleeding from undetermined sites by percutaneous selective coeliac and superior mesenteric arteriography. Surgery, 58: 797-805, 1965. 2. Baum, S., Rox, R., Finkelstein, A. K., and Blakemore, W. S.: Clinical application of selective coeliac and superior mesenteric arteriography. Radiology, 84:279-295, 1965. 3. Boijsen, E., Judkins, M. P., and Simay, A.: Angiocardiographic diagnosis of hepatic rupture. Radiology, 86:66, 1966. 4. Bosniak, M. A. and Phanthumachinoa, P.: Value of arteriography in the study of hepatic disease. Amer. J. Surg., 112:348, 1966. 5. Freeark, R. J., Kane, J. M., Folk, F. A., and Baker, R. J.: Traumatic disruptions of the head of the pancreas. Arch. Surg., 91:5-13, 1965. 6. Freeark, R. J., Love, L., and Baker, R. J.: Angiographic diagnosis of blunt abdominal trauma. J. Trauma (in press). 7. Freeark, R. J., Norcross, W. J., Corley, R. 0., and Strohl, E. L.: Intramural hematoma duodenum. Arch, Surg., 92:463-475, 1966. 8. Kirshen, R., Gambill, E., and Mason, H. L.: Comparison of urinary and serum amylase values following pancreatic stimulation in patients with and without pancreatic disease. Gastroenterology, 48:579, 1965. 9. Lange, K., Nagamatsu, G., and Altman, A.: Nonpenetrating abdominal trauma as a cause of renal vascular hypertension. J.A.M.A., 198:672-4, 1966. 10. McCort, J. J.: Radiographic Examination in Blunt Abdominal Trauma. Philadelphia, W. B. Saunders Co. 1966, pp. 58-60. 11. Nortell, H.: Traumatic rupture of the spleen diagnosed by abdominal aortography. Acta Radiol. 48:449-452, 1957. 12. Olsson, 0., and Lunderpuist, A.: Angiography in renal trauma. Acta Radiol., 1:1-21, 1963. 13. Pollard, J. J., and Nebesar, R. A.: Splenic rupture demonstrated by selective splenic artery angiogram. J.A.M.A., 187:944-945, 1964. 14. Root, H. D., Hauser, C. W., McKinley, R., Lafave, R. P., and Mendiola, R. P.: Diagnostic peritoneal lavage. Surgery, 57:633, 1965. 15. Seldinger, S. 1.: Catheter replacement of needle in percutaneous artericgraphy: New technique. Acta Radiol., 39:368-376, 1953. 16. Tindel, S., and Meyerowitz, B. R.: Unusual complication of diagnostic abdominal paracentesis. J.A.M.A., 193:838, 1965. 17. Williams, R. D., and Yurko, A. A., Jr.: Controversial aspects of diagnosis and management of blunt abdominal trauma. Am. J. Surg. 111 :4 77-482, 1966. 1825 West Harrison Street Chicago, Illinois 60612