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Newer Techniques in Evaluation of Injured Patients
Symposium on New Skills in Surgery
Newer Techniques in Evaluation of Injured Patients
Robert J. Baker, M.D. *
The incidence of civilian trauma in the United States has steadily increased in the past 20 years. Accidents are now the commonest cause of death between one and 35 years of age, and are fourth in all deaths reported, exceeded only by cardiac disease, cancer, and stroke. Despite the lower national speed limits imposed, a significant reduction in motor vehicle deaths has not been realized. Overall, more than 110,000 accidental deaths from all causes are reported, although 11 million Americans are hospitalized annually as a result of trauma, a truly staggering figure. It has been estimated that 22 million patient bed days are required in this group at a net medical-hospital cost of over three billion dollars annually.8. 9.12 The National Safety Council, the National Research Council, and a newly formed national organization, the American Trauma Society, have joined forces with regional and other national safety groups to combat the upward trend in this public health problem. Increasing population density, outdated highway systems, and myriad other factors have seemingly combined to limit any serious inroads into accident propensity in our population. The prospects for improving accident incidence statistics have brightened somewhat with the American Trauma Society activities, analogous to those of the American Heart Association and American Cancer Society in their respective spheres of interest. Nevertheless, it would appear that stringent, perhaps federally-supported, programs and legislation will be required. Since this is the case, those interested in management of the injured must apply themselves even more vigorously to improving methods of evaluating, treating, and rehabilitating the accident victim. Some basic techniques have been modified and improved, and newer techniques have been introduced to aid in evaluation and support of these patients, particularly in monitoring the critically ill and injured and in recognition of specific organ damage. -'Professor of Surgery, The Abraham Lincoln School of Medicine, University of Illinois at the Medical Center; Dean, Cook County Graduate School of Medicine Chicago, Illinois Surgical Clinics of North America- Vol. 55, No.1, February 1975
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EVALUATION OF TRAUMA MANAGEMENT A "trauma registry," or computerized evaluation of data pertaining to the injured, has been established in several trauma centers, including the Trauma Registry ofthe University of Illinois and the Cook County Hospital Trauma Unit. 2 This registry was designed to assess the mechanism of injury, method of transfer to a facility of choice, and nature and effectiveness of the final care delivery system. The National Research Council recognized the need for such a data-gathering device, and federal support for the several systems currently in use was forthcoming. It is anticipated that regionalization or'the U.S. will be required for significant data collection, specifically to obtain a broader spectrum of information about wounding agents, transportation problems, and "primary care" effectiveness. The Trauma Registry, designed by Boyd, employs computer-card tabulation for the primary collection process. Information sought includes epidemiologic considerations, anatomic damage incurred, type of treatment, and results. Although too comprehensive for routine use at this time, considering the necessary computer hardware and data-retrieving personnel required, expansion of this system will certainly benefit all practitioners concerned with care of the injured. The only requirement for data retrieval and interpretation is a request to the computer facility for information which is immediately forthcoming in all or several of the following categories: (1) computerized patient record, (2) clinical summaries of the injury, (3) treatment regime results, (4) risk factors (time, initial care), (5) morbidity-mortality data, (6) space-personnel requirements (logistic), and (7) cost projections. Ongoing investigative projects in specific areas, e.g., colon wound management and posttraumatic pulmonary insufficiency, can be surveyed by direct computer questioning. All information retrieval is by remote-terminal video screen readout in selected centers or by standard computer printout when query is made from other sites by telephone or mail. Despite the sometimes awe-inspiring complexity of such a system, this one has proved to be both workable and utilitarian and as such should be a major consideration in all trauma centers which contemplate service to their medical community and to injured patients.
GENERAL PRINCIPLES OF EVALUATION The conflict in Northern Ireland, at this writing, represents the only active military operation resulting in significant numbers of casualties. Several principles have evolved from that and previous concentrated experiences in assessing injured patients. Firstly, in active trauma centers, a senior physician interested in trauma should be in the Emergency Room or Trauma Unit around the clock. Obviously, there must be adequate numbers of injured patients to warrant such a manpower expenditure, but use of interns or relatively inexperienced physicians ignores the fact that mature judgment is
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needed to decide who is most seriously injured and what the priority of management of those injuries should be. This triage process has traditionally been left to the most junior and least experienced house officer, usually to the detriment of the patient.is Secondly, resuscitation of the critically ill and injured requires special knowledge, expertise, and judgment. It is anticipated now that a new specialist is on the horizon, one who will be expert in triage and resuscitation. Some efforts have been expended in this direction with the development of Emergency Room Physician or Emergency Medicine training programs, now appearing in numerous centers. However, care must be exercised that such individuals are sufficiently trained so that judgment in application of monitoring-resuscitation techniques will be sound under all circumstances. The "calm and collected" attitude must prevail in a new emergency center; "don't panic" is a principle that should be part of the basic training of all medical and paramedical personnel occupied with the care of the injured. Evaluating critically injured patients can best be approached as follows (Table 1): 1. Airway assessment can most rapidly be accomplished with the stethoscope and visual inspection of the chest wall. If breath sounds heard over the trachea are free of wet rales and rhonchi, the trachea is Inidline at the sternal notch, and adequate breath sounds are heard over both lung fields anteriorly and posteriorly, life-threatening airway damage can be ruled out. On the other hand, if the trachea is shifted to one side and breath sounds are diminished on the contralateral side, a needle thoracentesis should be quickly performed in the third interspace anteriorly. If blood and/or air are obtained, a chest tube should be inserted at the same level. The danger inherent in aspirating the chest in a lower interspace or in the Inidaxillary line is that the needle or thoracostomy catheter may penetrate a high diaphragm and enter a solid viscus; also, rupture of the diaphragm wi~h ·traumatic diaphragmatic hernia may be encountered and lower thoracentesis sites may yield gastric or colon content. Such accidents can be avoided if the third anterior interspace site is used. 2. An intra-arterial line is placed in all patients with chest injuries, Table 1. Evaluation of Injured Patients 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
Assess the airway Insert intravenous line Urinary catheter (or cystostomy) Infusion pyelogram Central venous pressure catheter Pulmonary artery, pulmonary artery wedge pressure catheters Arterial pH, Po" and Peo, Serum osmolality Paracentesis, sinography Visceral radionuclide scanning Angiography Frequent clinical observation
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all patients in shock refractory to immediate resuscitative efforts, and all patients with severe remote trauma who demonstrate persistent tachypnea or unexplained tachycardia. The usual site for such catheter insertion is the radial artery, although the brachial and femoral arteries are also employed. The appropriate catheter is one designed for intra-arterial use, constructed of polyethylene or polytetrafluoroethylene tubing,with a central metal trocar-tipped stylet. The advantage of this design lies in the fact that the trocar tip makes an arterial entry wound smaller than the catheter; when the catheter is advanced and the trocar removed, the catheter plugs the hole and makes a blood-tight fit, so that no periarterial hematoma results. The disadvantage with use of radial and brachial arteries is that these are small but vital vessels; if clot occludes the vessel, it may be necessary to operate upon the patient to reopen the channel. More satisfactory results have been obtained with cannulation of the femoral artery or the superficial temporal artery. The femoral artery is the largest channel considered for this purpose, and the easiest to cannulate. Further, protracted use of the vessel is extremely unlikely to cause obstruction even after several days. In instances where the patient is obese, or if the femoral pulse on either or both sides is weak or absent, the femoral artery should not be used. The superficial temporal artery, anterior to the ear, is readily approached by a simple, vertical cutdown incision 1 cm anterior to the tragus. The artery is ligated distally, and a fine polyethylene catheter is inserted 2 cm into the proximal vessel. It can be held in place by a single ligature. The end of the catheter is fitted with an adapter and a 3-way stopcock; a small syringe is connected to each limb of the stopcock. One syringe is empty, and is used for drawing blood samples; the second syringe contains 500 units of heparin in 5 ml of saline, 1.5 ml of which is used to fill the catheter after each blood sample is drawn. All blood samples are drawn via the intra-arterial catheter: P aH, P a02, P aC02' hematocrits, chemistries, osmolalities, etc. This obviates the need for venipuncture, and insures availability of blood for gas tensions and acid-base evaluation as often as is necessary. Superficial temporal artery cannulation is done through an incision which is hidden when the hair shaved for the cutdown grows back. There is little chance that an irrational or agitated patient in partial restraints will dislodge it, and prolonged catheterization with resultant thrombosis of the vessel will not result in tissue loss. The stopcock-syringe arrangement, although somewhat cumbersome, can be secured with a loosely applied roller bandage about the head. Although not ordinarily indicated, the catheter in any of the arteries can be connected to a strain gauge, transducer, and recorder and intra-arterial pressure readings obtained as often as desired. Blood pressure in traumatized patients is seldom of great moment, but if an element of myocardial insufficiency is present, such monitoring can be of considerable benefit, especially if alpha-receptor stimulator drugs are used. 3. Characteristically, critically ill surgical patients have urinary catheters placed as soon as feasible, frequently within the first few
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minutes in the hospital. The desire to monitor hourly urine output is based on the observation that adequate renal parenchymal blood flow will result in minimal flow rates of 0.5 ml urine secretion per minute, or 30 ml urine output per hour. Further, when oliguria occurs, steps must be taken to increase urinary flow by correcting oligemia, forcing diuresis with mannitol or furosemide, or recognizing and treating trauma to the urinary tract. Under certain circumstances, the injured male may suffer inestimable harm to the lower tract by the insertion of a urethral catheter. With serious pelvic fractures, 15 per cent of patients will sustain damage to the bladder or urethra. Of these, 60 per cent will have urethral trauma, 30 per cent bladder injury, and 10 per cent combined lesions. The classic signs of urethral injury are: a. Prostate is not 'palpable on rectal examination (the prostate floats free with high posterior urethral transection). b. Urethral bleeding is encountered or blood seen at the urethral meatus. c. The conscious patient cannot void, although the bladder is palpable on abdominal examination. d. Bloody urine is passed, but clears terminally. If catheterization is attempted with a ruptured upper urethra, a false passage will be made, or the tear in the urethra will be made worse, or perhaps periurethral urine will be obtained, leading to a significant delay in diagnosis. The contamination of the periurethral tissues which occurs when the catheter is mechanically introduced from below is the most serious consequence. Such infection prevents effective reconstruction of the severed urethra immediately, or even at a later date, and makes severe upper urethral stricture virtually a certainty. To forestall this possibility, any suggestion of urethral injury or of serious pelvic fracture requires that a retrograde urethrogram be done prior to other manipulation of the urinary tract. a. 4 A small Foley catheter is placed into the distal urethra, the balloon is gently inflated with air, and 20 to 25 ml of water-soluble dye (25 per cent diatrizoate) is injected slowly into the urethra from a sterile syringe. Oblique and lateral x-ray views are helpful in detecting small tears. If urethral damage is observed on the x-ray, urethral instrumentation is contraindicated and cystostomy must be performed. If no damage is seen, the catheter may be advanced into the bladder and cystography is then carried out. Urethrographic films must be studied prior to the performance of cystography, since extraperitoneal extravasation of dye from a ruptured bladder is not readily distinguishable from high posterior urethral rupture. Dye from this injury frequently enters the perivesical space. 4. Infusion pyelography has become almost routine in abdominal trauma or in patients with multiple injuries. Unless there is a history of dye sensitivity, 100 to 150 ml of 50 per cent diatrizoate is administered in the first liter of intravenous fluid infused. As soon as the patient is resuscitated, plain films of the abdomen are obtained to visualize the nephrographic phase. Renal enlargement on one side may indicate intraparenchymal hematoma or edema, whereas a localized nephrographic defect suggests an ischemic area or a laceration of the parenchyma. Extravasa-
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tion of contrast material from a pelvicalyceal tear is usually perinephric in location, although it may be subcapsular or intrarenal,14 When no visualization occurs on one side, there is generally vascular pedicle interruption or massive disruption of the kidney. With no opacification of either kidney, there is probably inadequate renal perfusion; rarely, bilateral renal vein thrombosis may also result in such a finding. Under any circumstances, atypical, abnormal, or absent visualization makes radionuclide study or angiography essential in further management. 5. Central venous pressure measurements have been widely used in the past 10 years with variable results. As originally described, hypovolemia resulted in low central venous pressure reading (below 3 cm of saline) and any type of fluid overload caused high central venous pressure (above 10 cm of saline). After several years of extensive clinical trial, two facts became evident: first, low central venous pressure has no practical clinical significance, as normovolemic patients may have a central venous pressure of zero; second, several entities may cause elevation of the central venous pressure, independent of blood volume. Myocardial disease, myocardial infarction, pulmonary hypertension, pericardial effusion, and colloid overload all have been noted to increase central venous pressure. More important, rapid crystalloid overinfusion, specifically with Ringer's lactate or saline, may result in pUlmonary edema although the central venous pressure remains normal. 6 The most reliable measurement for assessing intravascular volume is the left ventricular end diastolic, or filling, pressure. 16 Unfortunately, measurement of this parameter is not mechanically feasible. Other rightsided cardiac pressure measurements have proven to be suitable substitutes, far surpassing central venous pressure in reliability and accuracy. The most frequently employed of these are pulmonary artery end diastolic pressure and pulmonary artery wedge pressure. Both require the use of a balloon-tipped catheter, the Swan-Ganz, Elecath, or some similar device. These are introduced by cutdown into an antecubital or external jugular vein, and guided into position by portable fluoroscope or by electrocardiographic pattern change at the catheter tip as the catheter is introduced. The catheter, once placed in the pulmonary artery, is connected to a strain gauge transducer and recording deviceY Pressures are determined as often as necessary, frequently every 500 to 1000 ml fluid turnover. Pulmonary artery wedge pressure is measured by advancing the catheter and inflating the balloon to occlude a small radicle of the pulmonary artery. This modality is advantageous in that it is directly related to left atrial pressure when pulmonary vascular resistance is abnormally elevated, as is the case with the "shock lung" or interstitial edema syndromes. Routine use of capillary wedge pressure has been associated with peripheral lung ischemia, frank pulmonary infarction, embolism, and other mishaps.7 For this reason, pulmonary artery end diastolic' (or mean) pressure is frequently used and is of considerable value. Normal pulmonary capillary wedge pressure is 4 to 8 mm Hg, while normal pulmonary artery end diastolic pressure is 4 to 10 mm Hg. Increase in pulmonary capillary wedge pressure results from:
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a. Excessive intravenous fluid administration (colloid or crystalloid) b. Congestive heart failure c. Myocardial infarction d. Mitral valvular disease e. Interstitial edema Similarly, increase in mean pulmonary artery pressure results from: a. Pulmonary hypertension, primary or secondary b. Severe hypoxemia c. Severe acidosis d. Interstitial edema e. Excessive intravenous fluid administration f. Pulmonary embolism These catheters must be kept open with continuous intravenous fluid infusion, in a fashion similar to central venous pressure catheters, but generally with small amounts of heparin added to the infusate (0.1 mgm per ml of fluid) and with the rate of flow adjusted to a desirable level. 6. Arterial pH, Po 2 , and Pco 2 have become routine measurements in all seriously injured patients in the last few years. Automatic administration of large amounts of sodium bicarbonate to all traumatized patients has given way to cautious administration of buffer, the general rule calling for 89 mEqs of sodium (l00 ml of 7.5 per cent sodium bicarbonate) for every 0.1 pH unit fall below the normal of 7.38 to 7.42. Since alkalosis alters the oxygen dissociation curve (Bohr effect) with decreased oxyhemoglobin dissociation in the tissues, it is important to prevent excessive pH rise, either from injudicious alkali administration or by allowing the P aC02 to fall to extremely low levels. It would appear that administration of small amounts of carbon dioxide might be helpful if the P aC02 were to fall below 20 mm Hg. The adverse effect of low CO 2 tension on oxyhemoglobin dissociation is not related to the Bohr effect. Hypoxia, manifested by a fall in P a02 below 70 mm Hg, must be overcome. Further, it is unrewarding to measure arterial oxygen saturation with the patient lying in bed breathing room air. A tight-fitting rubber mask should be applied to the patient's face and oxygen administered at 12 liters per minute for 10 minutes prior to arterial blood sampling. The P a02 then assumes great importance, and all necessary therapeutic maneuvers should be utilized to keep the P a o 2 at an acceptable level, above 70 mm Hg. These include the use of the volume-controlled ventilator, endotracheal intubation, positive end-expiratory pressure and, under unusual circumstances, oxygen concentration in the inspired air in excess of 50 per cent. 7. Serum osmolality determination has proven to be extremely useful in critically injured and shock patients in the past few years.1 Recently developed instruments are inexpensive and reliable, making frequent and repeated measure of osmolality practical. Major trauma results in numerous metabolic changes, most of which cause the release of abnormal metabolites from intracellular sites to the extracellular fluid. The magnitude of increase of these metabolites is of great prognostic significance, since protracted, unremitting osmolality increase is associated with high mortality or extreme morbidity.
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Direct measurement and quantitation of the abnormal metabolites is not practical, but the overall increase in their osmotic effect is an excellent clinical approximation of the severity of the metabolic derangement. Normal serum osmolality can be calculated by the formula: . BUN Glucose Calculated Osmolality = Na+ (1.86) + ~ + 18
In injured patients, simultaneous determination of sodium, BUN, and glucose permits comparison of the calculated osmolality with the osmolality measured by the osmometer. If the difference (the measured always exceeds the calculated) is greater than 50 milliosmoles, significant amounts of abnormal substances have accumulated in the extracellular fluid. As treatment proceeds, the measured osmolality would be expected to fall toward the calculated value if the metabolic derangement is improving. If not, subcellular structure deterioration must be presumed to be progressive and other therapeutic efforts should be exerted (e.g., steroids in large doses, cardiotonic agents, alpha receptor blockers, etc.). 8. The use of abdominal paracentesis in trauma has been widely accepted. Needle aspiration of the peritoneal cavity is recommended if the patient is unconscious or intoxicated, if he has sustained spinal cord injury or has elevated serum or urine amylase, or if there is an unexplained fall in hematocrit. Paracentesis should not be used if there is an obvious indication for operation, tympanitic distention is present, or a pulsatile mass is felt. When gross blood or purulent fluid (microscopic examination) is obtained, operation is necessary. Peritoneal lavage is a particularly useful form of paracentesis when needle aspiration is not productive of diagnostic material. A peritoneal dialysis catheter is introduced under local anesthesia just inferior to the umbilicus, is secured with a pursestring suture, and 500 ml of buffered Ringer's lactate solution is introduced into the peritoneal cavity. The patient is gently turned from side to side, and the fluid is then allowed to return by gravity. The major problem with this technique is that of slightly bloody fluid return in blunt abdominal trauma patients. As previously described, 2 to 3 ml of blood in the 500 ml will cause a grossly bloody appearance, but should not make operation mandatory. When the returned fluid is bloody and the color depth is such that newsprint cannot be read through it, the test should be considered strongly positive and operation undertaken.tO Most important, neither negative needle aspiration nor lavage paracentesis with normal fluid return absolutely rules out significant intra-abdominal damage. Sinography has been advocated in the management of abdominal stabwounds to detect peritoneal penetration. 5 Since current management of stabwounds is based on the presence of physical signs of intra-abdominal injury, not on the demonstration of a traumatic peritoneal defect, this technique is no longer utilized. 9. Radionuclide scanning of various organs has been remarkably successful in demonstrating relatively symptomless injury, as well as in accurately delineating the extent of severe trauma. The noninvasive character of isotope-scanning techniques is obviously an attractive one,
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particularly in patients with multiple and complicating coexistent injuries. Older scanning devices made the procedure tedious and overlong, but the advent of rapid scanners and the gamma camera has obviated the delay and markedly increased accuracy. Brain scan has been widely used in head injury, and has been much more effective with the availability of 99mTc0 4 , the utilizable form of 99technetium. The scan shows increased uptake in certain traumatic lesions, specifically cerebral contusion, cerebral laceration, subdural hematoma, and epidural hematoma. Unfortunately, scalp ecchymoses and lacerations may confuse the interpretation, as the scalp is extremely vascular and collections of radioactivity may simulate intracranial lesions when none exist. With gamma camera scanning, four views may be "taken," as with skull x-rays; in addition, oblique or vertex views are sometimes obtained. 8 This technique is particularly valuable to exclude contrecoup lesions, when bilateral angiography might be undesirable. When the brain scan is positive, cerebral angiography is customarily employed for verification and precise localization of the lesion. Spleen scanning can be performed with 198Au or 99mTc-sulfur colloid. A scintillation scanner is quite satisfactory, but 99mTc-S-C coupled with gamma camera scanning appears to be the most rapid and reliable method. Anterior, posterior, left anterior oblique, and left posterior oblique views are obtained with the gamma camera. '8 Blurring of the margins of the spleen suggests subcapsular hematoma, whereas linear or wedge-shaped intrasplenic filling defects are seen with parenchymal laceration. If operation is not otherwise indicated, or if the blurred margin on scan suggests subcapsular hemorrhage, angiography should be done for confirmation. Liver scanning in trauma preceded other visceral scan procedures by almost a decade, but in many ways has proven to be the least valuable radionuclide study in the injured. Crushing abdominal injuries are often associated with major lobar destruction, but patients sustaining such injuries are seldom able to tolerate the time and manipulation necessary for a successful study. If the abdominal injury permits such a study, the liver disruption may be minimal, and the decision to operate will still be based on other findings. Further, when central right lobar damage has occurred, with occult necrotic areas within the liver parenchyma, the usual scintillation scanner study will not be helpful, and gamma camera serial tomographic sections of the liver will be required. Such scans can be obtained within 10 minutes after injection of 99mTc-sulfur colloid. 8 This latter technique is also particularly helpful in detecting parahepatic collections of pus, blood, or bile, and serial daily scans after repair of hepatic injury can be invaluable. Renal scanning has been the most widely applied scanning technique for detecting clinically important trauma. 197Hg chlormerodrin is the isotope now used most frequently, and the scan can be completed within 1 hour of injection." The scan is most helpful in the following circumstances: (a) if the infusion pyelogram shows no visualization on one side, the scan will demonstrate th~ presence of a kidney on the side in question, ruling out the possibility of congenital absence; (b) if the
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pyelogram shows no visualization on one side, and there is delayed or decreased uptake, arterial occlusion or segmental devascularization of the kidney is presumed; (c) when pyelographic dye extravasation is seen, the scan will delineate the site of injury. As a general rule, if the scan is normal, arteriography is not necessary, since the scan is quite reliable in surveying the traumatized kidney. Incidentally, when renal arterial repair is performed, an isotope bolus has been effectively used postoperatively to assess renal perfusion and the integrity of the vascular anastomosis. The overview of scanning techniques discussed illustrates the need for expensive and sophisticated radionuclide detection systems. Also, an experienced radiologist with a deep interest in emergency scanning procedures is a must. At this time, enthusiasm for the techniques must be tempered by the cost considerations; it is unlikely that more than one or two institutions in a given community will be able to support the personnel and equipment required. 10. Angiography in trauma is a well established and practical method for determining patency of major vascular channels as well as investigating the extent of injury to certain solid viscera. Unlike scanning, the technique is invasive, sometimes hazardous, and requires an experienced operator. On the other hand, equipment needs are simpler, less expensive, and much more widely available. Advantage can frequently be taken of the rapidity with which the films can be viewed; once performed, the results are available in minutes and a decision as to definitive treatment can be made on the spot. General considerations include the need to monitor the patient with multiple organ injury during the performance of the angiogram. If the patient is shipped off to the angiographic unit without an adequate team to carry out any type of required resuscitation, catastrophe is likely to follow. The hospital trauma team concept is most helpful here, since the physician doing the angiogram need not concern himself with the patient's general condition during the actual procedure. 13 Obviously, angiography is contraindicated if the patient is in shock or prior to effective resuscitation. The delay required to stabilize the cardiovascular system, develop an effective airway, immobilize fractures, and otherwise make the patient comfortable is time necessarily spent. Cerebral angiography has been extensively developed in various forms of intracranial disease, and has been extremely useful in all forms of cerebral trauma. Detection of a space occupying lesion is commonplace, and the absence of angiographic evidence of displacement with narrowing of distal arterial channels substantiates the presence of cerebral edema. The angiographic route to be used for dye introduction is conveniently percutaneous carotid puncture or catheter archogram via the brachial artery. A considerable advantage of the catheter archogram is that studies of abdominal viscera or arteries in any location can be performed by appropriate positioning of the catheter at or near the major vessels involved at the same time that cerebral angiography is obtained. Arteriography of peripheral vessels is necessary in nonpenetrating arterial trauma with weakness or loss of pulses distal to the injury. This
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study not only delineates the site of intramural dissection or transection of the vessel, but also demonstrates the patency of the outflow vessels, or "runoff." A strong case should be made for arteriography in any situation where a pulse deficit is detected. The concept of "spasm" as a cause of distal pulse weakness must be abandoned, as it occurs rarely, if at all. Compression of a vessel by hematoma and constricting fascia does occur, but the delay necessary to obtain the arteriogram is more than compensated for by the superior diagnostic accuracy. Diffuse, smooth narrowing of a vessel in an extremity seen on the arteriogram would definitely make fasciotomy the operation of choice. With penetrating wounds, arteriography often reveals arteriovenous fistula or false aneurysm, either of which are urgent indications for operation. Thoracoabdominal angiography is a valuable technique for detecting rupture of the thoracic aorta, abdominal aorta, spleen, liver, kidney, mesenteric vessels and may be helpful in locating bleeding sites in retroperitoneal hemorrhage of a massive type. The latter example is especially important if major pelvic fracture is the cause of the bleeding. Selective angiographic study of solid viscera can be extraordinarily explicit, and the site and extent of damage determined in advance of the operation. Particularly with liver and kidney, preoperative information can be infinitely more helpful than the operative findings. The angiographic operator must be experienced in selective catheterization techniques, however, since flush aortography is useless with liver injury and will be of no use in mesenteric or pelvic injury. Venography is not particularly helpful in acute trauma, and is seldom used.
SUMMARY Effective management of the severely injured requires an experienced, knowledgeable, and thoughtful physician who has a rational approach to both evaluation and treatment firmly in mind. When in doubt, access to a Trauma Registry (computerized) can be exceedingly valuable to assist in selecting the most effective treatment for a given clinical problem. The evaluation of the patient centers about general metabolic considerations, including acid-base disequilibrium, respiratory insufficiency, fluid volume monitoring, tissue perfusion (urine output), and osmolality. Diagnostic efforts to identify organ injury include infusion pyelography, paracentesis, radionuclide scanning, and angiography. The most critical diagnostic evaluation, however, remains frequent, careful examination of the injured patient, meticulously noting and interpreting all changes in physical findings.
REFERENCES 1. Boyd, D. R., Addis, H. M., Chilimindris, C., Lowe, R J., Folk, F. A., and Baker, R J.: Utilization of osmometry in critically ill surgical patients. Arch. Surg., 102:363-372, 1971. 2. Boyd, D. R, Lowe, R J., Baker, R J., and Nyhus, L. M.: Trauma registry, new computer method for multifactorial evaluation of a major health problem. J .A.M.A., 223 :422-428, 1973.
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3. Brosman, S. A., and Fay, R: Diagnosis and management of bladder trauma. J. Trauma, 13:687-694,1973. 4. Clark, S. S., and Prudencio, R F.: Lower urinary tract injuries associated with pelvic fractures. SURG. CLIN. N. AM., 52: 183-201, 1972. 5. Cornell, W. P., Ebert, P. A., Greenfield, L. J., and Zuidema, G. D.: A newnonoperative technique for the diagnosis of penetrating injuries to the abdomen. J. Trauma, 7:307-314, 1967. 6. DeLaurentis, D. A., Hayes, M., Matsumoto, T., and Wolferth, C. C.: Does central venous pressure accurately reflect hemodynamic and fluid volume patterns in the critical surgical patient? Am. J. Surg., 126:415-418, 1973.. 7. Foote, G. A., Schabel, S. I., and Hodges, M.: Pulmonary complications of the flow-directed balloon-tipped catheter. N. Eng. J. Med., 290:927-931, 1974. 8. Freedman, G. S.: Radionuclide imaging of the injured patient. RADIOL. CLIN. N. AM., 11:461-477,1973. 9. Glazier, W. H.: The task of medicine. Sci. Amer., 228:3-17, 1973. 10. Lowe, R J., Boyd, D. R, Folk, F. A., and Baker, R J.: The negative laparotomy for abdominal trauma. J. Trauma, 12:853-861, 1972. 11. Morse, T. S., and Harris, B. H.: Nonpenetrating renal vascular injuries. J. Trauma, 13:497501, 1973. 12. National Academy of Sciences, National Research Council, Committee on Trauma and Committee on Shock: Accidental Death and Disability: The Neglected Disease of Modern Society. Washington, NAS-NRC, 1966. 13. Osborn, D. J., Glickman, M. G., Grnja, V., and Ramsby, G.: The role of angiography in abdominal nonrenal trauma. RADIOL. CLIN. N. AM., 11 :579-592, 1973. 14. Richter, M. W., Lytton, B., Myerson, D., and Grnja, V.: Radiology of genitourinary trauma. RADIOL. CLIN. N. AM., 11 :593-638, 1973. 15. Rutherford, W. H.: Advances in traumatic surgery. Practitioner, 211 :427-433, 1973. 16. Sharefkin, J. B., and MacArthur, J. D.: Pulmonary arterial pressure as a guide to the hemodynamic status of surgical patients. Arch. Surg., 105:699-704, 1972. 17. Swan, H. J., Ganz, W., Forrester, J., Marcus, H., Diamond, G., and Chonette, D.: Catheterization of the heart in man with use of a flow-directed balloon-tipped catheter. N. Eng. J. Med., 283:447-451,1970. 18. Witek, J. T., Spencer, R. P., Pearson, H. A., and Touloukian, R J.: Diagnostic spleen scans in occult splenic injury. J. Trauma, 14:197-199, 1974.
The Abraham Lincoln School of Medicine University of Illinois at the Medical Center P.O. Box 6998 Chicago, Illinois 60680
Newer Techniques in Evaluation of Injured Patients
Robert J. Baker, M.D. *
The incidence of civilian trauma in the United States has steadily increased in the past 20 years. Accidents are now the commonest cause of death between one and 35 years of age, and are fourth in all deaths reported, exceeded only by cardiac disease, cancer, and stroke. Despite the lower national speed limits imposed, a significant reduction in motor vehicle deaths has not been realized. Overall, more than 110,000 accidental deaths from all causes are reported, although 11 million Americans are hospitalized annually as a result of trauma, a truly staggering figure. It has been estimated that 22 million patient bed days are required in this group at a net medical-hospital cost of over three billion dollars annually.8. 9.12 The National Safety Council, the National Research Council, and a newly formed national organization, the American Trauma Society, have joined forces with regional and other national safety groups to combat the upward trend in this public health problem. Increasing population density, outdated highway systems, and myriad other factors have seemingly combined to limit any serious inroads into accident propensity in our population. The prospects for improving accident incidence statistics have brightened somewhat with the American Trauma Society activities, analogous to those of the American Heart Association and American Cancer Society in their respective spheres of interest. Nevertheless, it would appear that stringent, perhaps federally-supported, programs and legislation will be required. Since this is the case, those interested in management of the injured must apply themselves even more vigorously to improving methods of evaluating, treating, and rehabilitating the accident victim. Some basic techniques have been modified and improved, and newer techniques have been introduced to aid in evaluation and support of these patients, particularly in monitoring the critically ill and injured and in recognition of specific organ damage. -'Professor of Surgery, The Abraham Lincoln School of Medicine, University of Illinois at the Medical Center; Dean, Cook County Graduate School of Medicine Chicago, Illinois Surgical Clinics of North America- Vol. 55, No.1, February 1975
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EVALUATION OF TRAUMA MANAGEMENT A "trauma registry," or computerized evaluation of data pertaining to the injured, has been established in several trauma centers, including the Trauma Registry ofthe University of Illinois and the Cook County Hospital Trauma Unit. 2 This registry was designed to assess the mechanism of injury, method of transfer to a facility of choice, and nature and effectiveness of the final care delivery system. The National Research Council recognized the need for such a data-gathering device, and federal support for the several systems currently in use was forthcoming. It is anticipated that regionalization or'the U.S. will be required for significant data collection, specifically to obtain a broader spectrum of information about wounding agents, transportation problems, and "primary care" effectiveness. The Trauma Registry, designed by Boyd, employs computer-card tabulation for the primary collection process. Information sought includes epidemiologic considerations, anatomic damage incurred, type of treatment, and results. Although too comprehensive for routine use at this time, considering the necessary computer hardware and data-retrieving personnel required, expansion of this system will certainly benefit all practitioners concerned with care of the injured. The only requirement for data retrieval and interpretation is a request to the computer facility for information which is immediately forthcoming in all or several of the following categories: (1) computerized patient record, (2) clinical summaries of the injury, (3) treatment regime results, (4) risk factors (time, initial care), (5) morbidity-mortality data, (6) space-personnel requirements (logistic), and (7) cost projections. Ongoing investigative projects in specific areas, e.g., colon wound management and posttraumatic pulmonary insufficiency, can be surveyed by direct computer questioning. All information retrieval is by remote-terminal video screen readout in selected centers or by standard computer printout when query is made from other sites by telephone or mail. Despite the sometimes awe-inspiring complexity of such a system, this one has proved to be both workable and utilitarian and as such should be a major consideration in all trauma centers which contemplate service to their medical community and to injured patients.
GENERAL PRINCIPLES OF EVALUATION The conflict in Northern Ireland, at this writing, represents the only active military operation resulting in significant numbers of casualties. Several principles have evolved from that and previous concentrated experiences in assessing injured patients. Firstly, in active trauma centers, a senior physician interested in trauma should be in the Emergency Room or Trauma Unit around the clock. Obviously, there must be adequate numbers of injured patients to warrant such a manpower expenditure, but use of interns or relatively inexperienced physicians ignores the fact that mature judgment is
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needed to decide who is most seriously injured and what the priority of management of those injuries should be. This triage process has traditionally been left to the most junior and least experienced house officer, usually to the detriment of the patient.is Secondly, resuscitation of the critically ill and injured requires special knowledge, expertise, and judgment. It is anticipated now that a new specialist is on the horizon, one who will be expert in triage and resuscitation. Some efforts have been expended in this direction with the development of Emergency Room Physician or Emergency Medicine training programs, now appearing in numerous centers. However, care must be exercised that such individuals are sufficiently trained so that judgment in application of monitoring-resuscitation techniques will be sound under all circumstances. The "calm and collected" attitude must prevail in a new emergency center; "don't panic" is a principle that should be part of the basic training of all medical and paramedical personnel occupied with the care of the injured. Evaluating critically injured patients can best be approached as follows (Table 1): 1. Airway assessment can most rapidly be accomplished with the stethoscope and visual inspection of the chest wall. If breath sounds heard over the trachea are free of wet rales and rhonchi, the trachea is Inidline at the sternal notch, and adequate breath sounds are heard over both lung fields anteriorly and posteriorly, life-threatening airway damage can be ruled out. On the other hand, if the trachea is shifted to one side and breath sounds are diminished on the contralateral side, a needle thoracentesis should be quickly performed in the third interspace anteriorly. If blood and/or air are obtained, a chest tube should be inserted at the same level. The danger inherent in aspirating the chest in a lower interspace or in the Inidaxillary line is that the needle or thoracostomy catheter may penetrate a high diaphragm and enter a solid viscus; also, rupture of the diaphragm wi~h ·traumatic diaphragmatic hernia may be encountered and lower thoracentesis sites may yield gastric or colon content. Such accidents can be avoided if the third anterior interspace site is used. 2. An intra-arterial line is placed in all patients with chest injuries, Table 1. Evaluation of Injured Patients 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
Assess the airway Insert intravenous line Urinary catheter (or cystostomy) Infusion pyelogram Central venous pressure catheter Pulmonary artery, pulmonary artery wedge pressure catheters Arterial pH, Po" and Peo, Serum osmolality Paracentesis, sinography Visceral radionuclide scanning Angiography Frequent clinical observation
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all patients in shock refractory to immediate resuscitative efforts, and all patients with severe remote trauma who demonstrate persistent tachypnea or unexplained tachycardia. The usual site for such catheter insertion is the radial artery, although the brachial and femoral arteries are also employed. The appropriate catheter is one designed for intra-arterial use, constructed of polyethylene or polytetrafluoroethylene tubing,with a central metal trocar-tipped stylet. The advantage of this design lies in the fact that the trocar tip makes an arterial entry wound smaller than the catheter; when the catheter is advanced and the trocar removed, the catheter plugs the hole and makes a blood-tight fit, so that no periarterial hematoma results. The disadvantage with use of radial and brachial arteries is that these are small but vital vessels; if clot occludes the vessel, it may be necessary to operate upon the patient to reopen the channel. More satisfactory results have been obtained with cannulation of the femoral artery or the superficial temporal artery. The femoral artery is the largest channel considered for this purpose, and the easiest to cannulate. Further, protracted use of the vessel is extremely unlikely to cause obstruction even after several days. In instances where the patient is obese, or if the femoral pulse on either or both sides is weak or absent, the femoral artery should not be used. The superficial temporal artery, anterior to the ear, is readily approached by a simple, vertical cutdown incision 1 cm anterior to the tragus. The artery is ligated distally, and a fine polyethylene catheter is inserted 2 cm into the proximal vessel. It can be held in place by a single ligature. The end of the catheter is fitted with an adapter and a 3-way stopcock; a small syringe is connected to each limb of the stopcock. One syringe is empty, and is used for drawing blood samples; the second syringe contains 500 units of heparin in 5 ml of saline, 1.5 ml of which is used to fill the catheter after each blood sample is drawn. All blood samples are drawn via the intra-arterial catheter: P aH, P a02, P aC02' hematocrits, chemistries, osmolalities, etc. This obviates the need for venipuncture, and insures availability of blood for gas tensions and acid-base evaluation as often as is necessary. Superficial temporal artery cannulation is done through an incision which is hidden when the hair shaved for the cutdown grows back. There is little chance that an irrational or agitated patient in partial restraints will dislodge it, and prolonged catheterization with resultant thrombosis of the vessel will not result in tissue loss. The stopcock-syringe arrangement, although somewhat cumbersome, can be secured with a loosely applied roller bandage about the head. Although not ordinarily indicated, the catheter in any of the arteries can be connected to a strain gauge, transducer, and recorder and intra-arterial pressure readings obtained as often as desired. Blood pressure in traumatized patients is seldom of great moment, but if an element of myocardial insufficiency is present, such monitoring can be of considerable benefit, especially if alpha-receptor stimulator drugs are used. 3. Characteristically, critically ill surgical patients have urinary catheters placed as soon as feasible, frequently within the first few
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minutes in the hospital. The desire to monitor hourly urine output is based on the observation that adequate renal parenchymal blood flow will result in minimal flow rates of 0.5 ml urine secretion per minute, or 30 ml urine output per hour. Further, when oliguria occurs, steps must be taken to increase urinary flow by correcting oligemia, forcing diuresis with mannitol or furosemide, or recognizing and treating trauma to the urinary tract. Under certain circumstances, the injured male may suffer inestimable harm to the lower tract by the insertion of a urethral catheter. With serious pelvic fractures, 15 per cent of patients will sustain damage to the bladder or urethra. Of these, 60 per cent will have urethral trauma, 30 per cent bladder injury, and 10 per cent combined lesions. The classic signs of urethral injury are: a. Prostate is not 'palpable on rectal examination (the prostate floats free with high posterior urethral transection). b. Urethral bleeding is encountered or blood seen at the urethral meatus. c. The conscious patient cannot void, although the bladder is palpable on abdominal examination. d. Bloody urine is passed, but clears terminally. If catheterization is attempted with a ruptured upper urethra, a false passage will be made, or the tear in the urethra will be made worse, or perhaps periurethral urine will be obtained, leading to a significant delay in diagnosis. The contamination of the periurethral tissues which occurs when the catheter is mechanically introduced from below is the most serious consequence. Such infection prevents effective reconstruction of the severed urethra immediately, or even at a later date, and makes severe upper urethral stricture virtually a certainty. To forestall this possibility, any suggestion of urethral injury or of serious pelvic fracture requires that a retrograde urethrogram be done prior to other manipulation of the urinary tract. a. 4 A small Foley catheter is placed into the distal urethra, the balloon is gently inflated with air, and 20 to 25 ml of water-soluble dye (25 per cent diatrizoate) is injected slowly into the urethra from a sterile syringe. Oblique and lateral x-ray views are helpful in detecting small tears. If urethral damage is observed on the x-ray, urethral instrumentation is contraindicated and cystostomy must be performed. If no damage is seen, the catheter may be advanced into the bladder and cystography is then carried out. Urethrographic films must be studied prior to the performance of cystography, since extraperitoneal extravasation of dye from a ruptured bladder is not readily distinguishable from high posterior urethral rupture. Dye from this injury frequently enters the perivesical space. 4. Infusion pyelography has become almost routine in abdominal trauma or in patients with multiple injuries. Unless there is a history of dye sensitivity, 100 to 150 ml of 50 per cent diatrizoate is administered in the first liter of intravenous fluid infused. As soon as the patient is resuscitated, plain films of the abdomen are obtained to visualize the nephrographic phase. Renal enlargement on one side may indicate intraparenchymal hematoma or edema, whereas a localized nephrographic defect suggests an ischemic area or a laceration of the parenchyma. Extravasa-
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tion of contrast material from a pelvicalyceal tear is usually perinephric in location, although it may be subcapsular or intrarenal,14 When no visualization occurs on one side, there is generally vascular pedicle interruption or massive disruption of the kidney. With no opacification of either kidney, there is probably inadequate renal perfusion; rarely, bilateral renal vein thrombosis may also result in such a finding. Under any circumstances, atypical, abnormal, or absent visualization makes radionuclide study or angiography essential in further management. 5. Central venous pressure measurements have been widely used in the past 10 years with variable results. As originally described, hypovolemia resulted in low central venous pressure reading (below 3 cm of saline) and any type of fluid overload caused high central venous pressure (above 10 cm of saline). After several years of extensive clinical trial, two facts became evident: first, low central venous pressure has no practical clinical significance, as normovolemic patients may have a central venous pressure of zero; second, several entities may cause elevation of the central venous pressure, independent of blood volume. Myocardial disease, myocardial infarction, pulmonary hypertension, pericardial effusion, and colloid overload all have been noted to increase central venous pressure. More important, rapid crystalloid overinfusion, specifically with Ringer's lactate or saline, may result in pUlmonary edema although the central venous pressure remains normal. 6 The most reliable measurement for assessing intravascular volume is the left ventricular end diastolic, or filling, pressure. 16 Unfortunately, measurement of this parameter is not mechanically feasible. Other rightsided cardiac pressure measurements have proven to be suitable substitutes, far surpassing central venous pressure in reliability and accuracy. The most frequently employed of these are pulmonary artery end diastolic pressure and pulmonary artery wedge pressure. Both require the use of a balloon-tipped catheter, the Swan-Ganz, Elecath, or some similar device. These are introduced by cutdown into an antecubital or external jugular vein, and guided into position by portable fluoroscope or by electrocardiographic pattern change at the catheter tip as the catheter is introduced. The catheter, once placed in the pulmonary artery, is connected to a strain gauge transducer and recording deviceY Pressures are determined as often as necessary, frequently every 500 to 1000 ml fluid turnover. Pulmonary artery wedge pressure is measured by advancing the catheter and inflating the balloon to occlude a small radicle of the pulmonary artery. This modality is advantageous in that it is directly related to left atrial pressure when pulmonary vascular resistance is abnormally elevated, as is the case with the "shock lung" or interstitial edema syndromes. Routine use of capillary wedge pressure has been associated with peripheral lung ischemia, frank pulmonary infarction, embolism, and other mishaps.7 For this reason, pulmonary artery end diastolic' (or mean) pressure is frequently used and is of considerable value. Normal pulmonary capillary wedge pressure is 4 to 8 mm Hg, while normal pulmonary artery end diastolic pressure is 4 to 10 mm Hg. Increase in pulmonary capillary wedge pressure results from:
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a. Excessive intravenous fluid administration (colloid or crystalloid) b. Congestive heart failure c. Myocardial infarction d. Mitral valvular disease e. Interstitial edema Similarly, increase in mean pulmonary artery pressure results from: a. Pulmonary hypertension, primary or secondary b. Severe hypoxemia c. Severe acidosis d. Interstitial edema e. Excessive intravenous fluid administration f. Pulmonary embolism These catheters must be kept open with continuous intravenous fluid infusion, in a fashion similar to central venous pressure catheters, but generally with small amounts of heparin added to the infusate (0.1 mgm per ml of fluid) and with the rate of flow adjusted to a desirable level. 6. Arterial pH, Po 2 , and Pco 2 have become routine measurements in all seriously injured patients in the last few years. Automatic administration of large amounts of sodium bicarbonate to all traumatized patients has given way to cautious administration of buffer, the general rule calling for 89 mEqs of sodium (l00 ml of 7.5 per cent sodium bicarbonate) for every 0.1 pH unit fall below the normal of 7.38 to 7.42. Since alkalosis alters the oxygen dissociation curve (Bohr effect) with decreased oxyhemoglobin dissociation in the tissues, it is important to prevent excessive pH rise, either from injudicious alkali administration or by allowing the P aC02 to fall to extremely low levels. It would appear that administration of small amounts of carbon dioxide might be helpful if the P aC02 were to fall below 20 mm Hg. The adverse effect of low CO 2 tension on oxyhemoglobin dissociation is not related to the Bohr effect. Hypoxia, manifested by a fall in P a02 below 70 mm Hg, must be overcome. Further, it is unrewarding to measure arterial oxygen saturation with the patient lying in bed breathing room air. A tight-fitting rubber mask should be applied to the patient's face and oxygen administered at 12 liters per minute for 10 minutes prior to arterial blood sampling. The P a02 then assumes great importance, and all necessary therapeutic maneuvers should be utilized to keep the P a o 2 at an acceptable level, above 70 mm Hg. These include the use of the volume-controlled ventilator, endotracheal intubation, positive end-expiratory pressure and, under unusual circumstances, oxygen concentration in the inspired air in excess of 50 per cent. 7. Serum osmolality determination has proven to be extremely useful in critically injured and shock patients in the past few years.1 Recently developed instruments are inexpensive and reliable, making frequent and repeated measure of osmolality practical. Major trauma results in numerous metabolic changes, most of which cause the release of abnormal metabolites from intracellular sites to the extracellular fluid. The magnitude of increase of these metabolites is of great prognostic significance, since protracted, unremitting osmolality increase is associated with high mortality or extreme morbidity.
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Direct measurement and quantitation of the abnormal metabolites is not practical, but the overall increase in their osmotic effect is an excellent clinical approximation of the severity of the metabolic derangement. Normal serum osmolality can be calculated by the formula: . BUN Glucose Calculated Osmolality = Na+ (1.86) + ~ + 18
In injured patients, simultaneous determination of sodium, BUN, and glucose permits comparison of the calculated osmolality with the osmolality measured by the osmometer. If the difference (the measured always exceeds the calculated) is greater than 50 milliosmoles, significant amounts of abnormal substances have accumulated in the extracellular fluid. As treatment proceeds, the measured osmolality would be expected to fall toward the calculated value if the metabolic derangement is improving. If not, subcellular structure deterioration must be presumed to be progressive and other therapeutic efforts should be exerted (e.g., steroids in large doses, cardiotonic agents, alpha receptor blockers, etc.). 8. The use of abdominal paracentesis in trauma has been widely accepted. Needle aspiration of the peritoneal cavity is recommended if the patient is unconscious or intoxicated, if he has sustained spinal cord injury or has elevated serum or urine amylase, or if there is an unexplained fall in hematocrit. Paracentesis should not be used if there is an obvious indication for operation, tympanitic distention is present, or a pulsatile mass is felt. When gross blood or purulent fluid (microscopic examination) is obtained, operation is necessary. Peritoneal lavage is a particularly useful form of paracentesis when needle aspiration is not productive of diagnostic material. A peritoneal dialysis catheter is introduced under local anesthesia just inferior to the umbilicus, is secured with a pursestring suture, and 500 ml of buffered Ringer's lactate solution is introduced into the peritoneal cavity. The patient is gently turned from side to side, and the fluid is then allowed to return by gravity. The major problem with this technique is that of slightly bloody fluid return in blunt abdominal trauma patients. As previously described, 2 to 3 ml of blood in the 500 ml will cause a grossly bloody appearance, but should not make operation mandatory. When the returned fluid is bloody and the color depth is such that newsprint cannot be read through it, the test should be considered strongly positive and operation undertaken.tO Most important, neither negative needle aspiration nor lavage paracentesis with normal fluid return absolutely rules out significant intra-abdominal damage. Sinography has been advocated in the management of abdominal stabwounds to detect peritoneal penetration. 5 Since current management of stabwounds is based on the presence of physical signs of intra-abdominal injury, not on the demonstration of a traumatic peritoneal defect, this technique is no longer utilized. 9. Radionuclide scanning of various organs has been remarkably successful in demonstrating relatively symptomless injury, as well as in accurately delineating the extent of severe trauma. The noninvasive character of isotope-scanning techniques is obviously an attractive one,
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particularly in patients with multiple and complicating coexistent injuries. Older scanning devices made the procedure tedious and overlong, but the advent of rapid scanners and the gamma camera has obviated the delay and markedly increased accuracy. Brain scan has been widely used in head injury, and has been much more effective with the availability of 99mTc0 4 , the utilizable form of 99technetium. The scan shows increased uptake in certain traumatic lesions, specifically cerebral contusion, cerebral laceration, subdural hematoma, and epidural hematoma. Unfortunately, scalp ecchymoses and lacerations may confuse the interpretation, as the scalp is extremely vascular and collections of radioactivity may simulate intracranial lesions when none exist. With gamma camera scanning, four views may be "taken," as with skull x-rays; in addition, oblique or vertex views are sometimes obtained. 8 This technique is particularly valuable to exclude contrecoup lesions, when bilateral angiography might be undesirable. When the brain scan is positive, cerebral angiography is customarily employed for verification and precise localization of the lesion. Spleen scanning can be performed with 198Au or 99mTc-sulfur colloid. A scintillation scanner is quite satisfactory, but 99mTc-S-C coupled with gamma camera scanning appears to be the most rapid and reliable method. Anterior, posterior, left anterior oblique, and left posterior oblique views are obtained with the gamma camera. '8 Blurring of the margins of the spleen suggests subcapsular hematoma, whereas linear or wedge-shaped intrasplenic filling defects are seen with parenchymal laceration. If operation is not otherwise indicated, or if the blurred margin on scan suggests subcapsular hemorrhage, angiography should be done for confirmation. Liver scanning in trauma preceded other visceral scan procedures by almost a decade, but in many ways has proven to be the least valuable radionuclide study in the injured. Crushing abdominal injuries are often associated with major lobar destruction, but patients sustaining such injuries are seldom able to tolerate the time and manipulation necessary for a successful study. If the abdominal injury permits such a study, the liver disruption may be minimal, and the decision to operate will still be based on other findings. Further, when central right lobar damage has occurred, with occult necrotic areas within the liver parenchyma, the usual scintillation scanner study will not be helpful, and gamma camera serial tomographic sections of the liver will be required. Such scans can be obtained within 10 minutes after injection of 99mTc-sulfur colloid. 8 This latter technique is also particularly helpful in detecting parahepatic collections of pus, blood, or bile, and serial daily scans after repair of hepatic injury can be invaluable. Renal scanning has been the most widely applied scanning technique for detecting clinically important trauma. 197Hg chlormerodrin is the isotope now used most frequently, and the scan can be completed within 1 hour of injection." The scan is most helpful in the following circumstances: (a) if the infusion pyelogram shows no visualization on one side, the scan will demonstrate th~ presence of a kidney on the side in question, ruling out the possibility of congenital absence; (b) if the
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pyelogram shows no visualization on one side, and there is delayed or decreased uptake, arterial occlusion or segmental devascularization of the kidney is presumed; (c) when pyelographic dye extravasation is seen, the scan will delineate the site of injury. As a general rule, if the scan is normal, arteriography is not necessary, since the scan is quite reliable in surveying the traumatized kidney. Incidentally, when renal arterial repair is performed, an isotope bolus has been effectively used postoperatively to assess renal perfusion and the integrity of the vascular anastomosis. The overview of scanning techniques discussed illustrates the need for expensive and sophisticated radionuclide detection systems. Also, an experienced radiologist with a deep interest in emergency scanning procedures is a must. At this time, enthusiasm for the techniques must be tempered by the cost considerations; it is unlikely that more than one or two institutions in a given community will be able to support the personnel and equipment required. 10. Angiography in trauma is a well established and practical method for determining patency of major vascular channels as well as investigating the extent of injury to certain solid viscera. Unlike scanning, the technique is invasive, sometimes hazardous, and requires an experienced operator. On the other hand, equipment needs are simpler, less expensive, and much more widely available. Advantage can frequently be taken of the rapidity with which the films can be viewed; once performed, the results are available in minutes and a decision as to definitive treatment can be made on the spot. General considerations include the need to monitor the patient with multiple organ injury during the performance of the angiogram. If the patient is shipped off to the angiographic unit without an adequate team to carry out any type of required resuscitation, catastrophe is likely to follow. The hospital trauma team concept is most helpful here, since the physician doing the angiogram need not concern himself with the patient's general condition during the actual procedure. 13 Obviously, angiography is contraindicated if the patient is in shock or prior to effective resuscitation. The delay required to stabilize the cardiovascular system, develop an effective airway, immobilize fractures, and otherwise make the patient comfortable is time necessarily spent. Cerebral angiography has been extensively developed in various forms of intracranial disease, and has been extremely useful in all forms of cerebral trauma. Detection of a space occupying lesion is commonplace, and the absence of angiographic evidence of displacement with narrowing of distal arterial channels substantiates the presence of cerebral edema. The angiographic route to be used for dye introduction is conveniently percutaneous carotid puncture or catheter archogram via the brachial artery. A considerable advantage of the catheter archogram is that studies of abdominal viscera or arteries in any location can be performed by appropriate positioning of the catheter at or near the major vessels involved at the same time that cerebral angiography is obtained. Arteriography of peripheral vessels is necessary in nonpenetrating arterial trauma with weakness or loss of pulses distal to the injury. This
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study not only delineates the site of intramural dissection or transection of the vessel, but also demonstrates the patency of the outflow vessels, or "runoff." A strong case should be made for arteriography in any situation where a pulse deficit is detected. The concept of "spasm" as a cause of distal pulse weakness must be abandoned, as it occurs rarely, if at all. Compression of a vessel by hematoma and constricting fascia does occur, but the delay necessary to obtain the arteriogram is more than compensated for by the superior diagnostic accuracy. Diffuse, smooth narrowing of a vessel in an extremity seen on the arteriogram would definitely make fasciotomy the operation of choice. With penetrating wounds, arteriography often reveals arteriovenous fistula or false aneurysm, either of which are urgent indications for operation. Thoracoabdominal angiography is a valuable technique for detecting rupture of the thoracic aorta, abdominal aorta, spleen, liver, kidney, mesenteric vessels and may be helpful in locating bleeding sites in retroperitoneal hemorrhage of a massive type. The latter example is especially important if major pelvic fracture is the cause of the bleeding. Selective angiographic study of solid viscera can be extraordinarily explicit, and the site and extent of damage determined in advance of the operation. Particularly with liver and kidney, preoperative information can be infinitely more helpful than the operative findings. The angiographic operator must be experienced in selective catheterization techniques, however, since flush aortography is useless with liver injury and will be of no use in mesenteric or pelvic injury. Venography is not particularly helpful in acute trauma, and is seldom used.
SUMMARY Effective management of the severely injured requires an experienced, knowledgeable, and thoughtful physician who has a rational approach to both evaluation and treatment firmly in mind. When in doubt, access to a Trauma Registry (computerized) can be exceedingly valuable to assist in selecting the most effective treatment for a given clinical problem. The evaluation of the patient centers about general metabolic considerations, including acid-base disequilibrium, respiratory insufficiency, fluid volume monitoring, tissue perfusion (urine output), and osmolality. Diagnostic efforts to identify organ injury include infusion pyelography, paracentesis, radionuclide scanning, and angiography. The most critical diagnostic evaluation, however, remains frequent, careful examination of the injured patient, meticulously noting and interpreting all changes in physical findings.
REFERENCES 1. Boyd, D. R., Addis, H. M., Chilimindris, C., Lowe, R J., Folk, F. A., and Baker, R J.: Utilization of osmometry in critically ill surgical patients. Arch. Surg., 102:363-372, 1971. 2. Boyd, D. R, Lowe, R J., Baker, R J., and Nyhus, L. M.: Trauma registry, new computer method for multifactorial evaluation of a major health problem. J .A.M.A., 223 :422-428, 1973.
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3. Brosman, S. A., and Fay, R: Diagnosis and management of bladder trauma. J. Trauma, 13:687-694,1973. 4. Clark, S. S., and Prudencio, R F.: Lower urinary tract injuries associated with pelvic fractures. SURG. CLIN. N. AM., 52: 183-201, 1972. 5. Cornell, W. P., Ebert, P. A., Greenfield, L. J., and Zuidema, G. D.: A newnonoperative technique for the diagnosis of penetrating injuries to the abdomen. J. Trauma, 7:307-314, 1967. 6. DeLaurentis, D. A., Hayes, M., Matsumoto, T., and Wolferth, C. C.: Does central venous pressure accurately reflect hemodynamic and fluid volume patterns in the critical surgical patient? Am. J. Surg., 126:415-418, 1973.. 7. Foote, G. A., Schabel, S. I., and Hodges, M.: Pulmonary complications of the flow-directed balloon-tipped catheter. N. Eng. J. Med., 290:927-931, 1974. 8. Freedman, G. S.: Radionuclide imaging of the injured patient. RADIOL. CLIN. N. AM., 11:461-477,1973. 9. Glazier, W. H.: The task of medicine. Sci. Amer., 228:3-17, 1973. 10. Lowe, R J., Boyd, D. R, Folk, F. A., and Baker, R J.: The negative laparotomy for abdominal trauma. J. Trauma, 12:853-861, 1972. 11. Morse, T. S., and Harris, B. H.: Nonpenetrating renal vascular injuries. J. Trauma, 13:497501, 1973. 12. National Academy of Sciences, National Research Council, Committee on Trauma and Committee on Shock: Accidental Death and Disability: The Neglected Disease of Modern Society. Washington, NAS-NRC, 1966. 13. Osborn, D. J., Glickman, M. G., Grnja, V., and Ramsby, G.: The role of angiography in abdominal nonrenal trauma. RADIOL. CLIN. N. AM., 11 :579-592, 1973. 14. Richter, M. W., Lytton, B., Myerson, D., and Grnja, V.: Radiology of genitourinary trauma. RADIOL. CLIN. N. AM., 11 :593-638, 1973. 15. Rutherford, W. H.: Advances in traumatic surgery. Practitioner, 211 :427-433, 1973. 16. Sharefkin, J. B., and MacArthur, J. D.: Pulmonary arterial pressure as a guide to the hemodynamic status of surgical patients. Arch. Surg., 105:699-704, 1972. 17. Swan, H. J., Ganz, W., Forrester, J., Marcus, H., Diamond, G., and Chonette, D.: Catheterization of the heart in man with use of a flow-directed balloon-tipped catheter. N. Eng. J. Med., 283:447-451,1970. 18. Witek, J. T., Spencer, R. P., Pearson, H. A., and Touloukian, R J.: Diagnostic spleen scans in occult splenic injury. J. Trauma, 14:197-199, 1974.
The Abraham Lincoln School of Medicine University of Illinois at the Medical Center P.O. Box 6998 Chicago, Illinois 60680