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Extension of Subdiaphragmatic Disease Processes into the Thoracic Cavity
Extension of Subdiaphragmatic Disease Processes into the Thoracic Cavity HERBERT D. ADAMS, M.D.
ANATOMICALLY, the diaphragm acts as an effective partition between the thorax and the abdomen. We have already discussed the results of defects (herniation) in this structure but it is also important to point out that the diaphragm is not an entirely effective barrier to the extension of infection and tumor from the abdomen to the thorax. Extension of infection or tumor from the organs beneath the diaphragm, such as the liver, biliary tract, stomach or pancreas, to or through the diaphragm does occasionally occur. Liver abscess or subdiaphragmatic abscess, if not adequately drained, will perforate the diaphragm. The incidence of such abscesses has been materially reduced by the widespread use of antibiotics, although they have not been entirely eliminated by chemotherapy. In some instances the use of antibiotics has obscured the true status and progress of the abscess has led to further and more serious complications. Since these abscesses still exist, even though at present their frequency is greatly reduced, it is well to review the present status of the management and treatment of such disease processes. Infection beneath the diaphragm or in relation to the several surfaces of the liver is most commonly a postoperative complication following many types of abdominal operations. In the postoperative period, if clinical signs of obscure infection develop and when the more common sources of such infection, such as a residual abscess in the operative field, the wound, urinary tract or respiratory system, have been ruled out, attention must be focused on the subdiaphragmatic region for residual or possible extension of infection. If there has not been any antecedent abdominal operation or known source of intra-abdominal infection, a primary pyogenic abscess of the liver or a secondarily infected echinococcus or amebic abscess may involve the diaphragm. Pyogenic liver abscess or more commonly multiple liver abscesses are usually the sequelae of pyelophlebitis. With clinical signs of progressive sepsis in which the source is obscured, a focus of 847
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infection in the liver may not become apparent until signs of diaphragmatic involvement develop. Frequently it is possible to localize the infection in this general region, but the accurate differentiation from (1) basal pleural infection, (2) sUbdiaphragmatic or perihepatic infection, (3) intrahepatic or liver abscess, and (4) subhepatic, perirenal, perisplenic or pancreatic infection may be extremely difficult. The diagnosis and localization of such abscesses, however, may be accomplished by careful clinical observation, roentgenographic studies, diagnostic aspiration and, if necessary, by exploratory operation. The diagnostic procedure of greatest value is roentgenographic examination. Roentgenograms are taken with the patient in three positions: anteroposterior, sitting up; anteroposterior, lying on the side (lateral decubitus) with the affected side up, and a lateral film with the patient sitting up. These three views in these positions will frequently demonstrate a shifting collection of gas beneath the diaphragm which would be obscure in routine films taken with the patient lying on his back. Even when a shifting collection of gas cannot be demonstrated and the roentgenograms show a diaphragm elevated and obscured by a basal pleural reaction, a subphrenic abscess may still be present. Basal empyema and intrahepatic or even subhepatic abscess, such as in the bed of the gallbladder or Morison's pouch, will often give identical x-ray pictures. Localization of an abscess under the left diaphragm by roentgenography is even more difficult. Owing to the anatomical relation of the left lobe of the liver, the stomach and the spleen to the diaphragm, an abscess is more likely to dissect around or between these structures rather than to present a major part of its surface to the diaphragm, such as it does over the dome of the right lobe of the liver. As a result, little reaction may be demonstrable above the diaphragm, or the presence of a shifting collection of gas below the diaphragm may not be apparent on the roentgenogram. The most valuable diagnostic finding on the left side is an abnormal displacement or distortion of the air bubble in the fundus of the stomach. This detail should be carefully observed at fluoroscopy and the films should be taken at different angles. If a shifting gas bubble cannot be demonstrated on properly-taken films, diagnostic aspiration should be considered. In most instances the diaphragm rises high and the costophrenic pleural angles are obliterated so that aspiration is usually safe from pleural contamination. This procedure is warranted especially if the patient is extremely ill and his condition demands immediate localization of the infection and adequate surgical drainage. Another practical point with reference to diagnostic aspiration is the fact that pus, presumably obtained from the pleural cavity during thoracentesis for what appears to be a basal empyema, may actually be aspirated from beneath a high, obscure diaphragm, and an erroneous localization be assumed. If this happens the patient will invariably complain of pain at the top of his shoulder as the needle en-
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counters the diaphragm. If pus is aspirated before such a diaphragmatic reference of pain is elicited, the infection is in the pleural cavity; if pus is aspirated after diaphragmatic pain is elicited, the infection is below the diaphragm. Therefore, it is essential that the surgeon be alert to this helpful localizing diagnostic sign. Finally, surgical exploration of the subphrenic region is justified in cases in which decline is rapid as a result of obscure infection and when roentgenography and attempted aspiration have failed to yield evidence for a definite diagnosis even though there is reasonably positive clinical and x-ray evidence that subdiaphragmatic infection exists. Exploration can readily be performed under local anesthesia with virtually no risk to the patient, and this may well be a life-saving measure. The surgical approach for drainage of a subdiaphragmatic abscess in the posterior inferior subphrenic space is through one of two routes. The first approach is through the bed of the resected twelfth rib i by blunt dissection retroperitoneally and extrapleurally (Fig. 1, a) the subdiaphragmatic space it involves is broken into and drained. This has the advantage of avoiding the pleura and possible contamination of this space in most cases, but has the disadvantage that a much greater amount of tissue must be traversed from this lower level to reach these invariably high collections of pus under the diaphragm and a much longer and less direct drainage tract must be maintained. In addition, it is well to remember that owing to anatomical variations the pleural reflection will be encountered as low as the twelfth rib in 30 to 40 per cent of the cases. Therefore, we favor the second, more direct route at a higher level, electively crossing the lower costophrenic reflections of the pleura. A posterior segment of the eleventh rib is resected and a corresponding length of its intercostal bundle removed to enlarge the exposed surface of the parietal pleura. Care must be taken at this point not to open the pleura to avoid contamination and pneumothorax. If the costophrenic pleural reflection has not been obliterated by the inflammatory process, which can readily be determined by the appearance of the pleura and observing the two surfaces sliding free on each other or being held apart by fluid, one of two methods of obliterating the costopleural angle must be carried out. A firm gauze pack placed against the exposed parietal pleura and left in place for 48 hours will effectively seal off the pleura. This has the distinct disadvantage of requiring a two stage procedure with several days' delay before the final drainage is accomplished and the patient relieved of marked signs of infection. If the time element because of the patient's condition is important-which is usually the case-the costophrenic pleural surfaces can be sutured together with fine interrupted sutures placed around the entire periphery of the exposed pleura (Fig. 1, b); the pleura and diaphragm beneath it are opened directly into the abscess by an incision in the center of this isolated
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Fig. 1. a, Drainage of a subdiaphragmatic abscess in bed of the eleventh rib. b, Method of obliterating the costophrenic pleural reflection.
section of parietal and diaphragmatic pleura without fear of contamination of the pleural cavity. The abscess can readily be reached through this approach and excellent and direct drainage obtained. The drainage is maintained by inserting a soft rubber chest tube or cigarette drain with a small catheter for irrigation and instillation of the proper antibiotic agent. Anterior space and subhepatic infections can be drained satisfactorily through a subcostal incision several inches to the right of the xiphoid process, carrying the dissection upward close to the under surface of the costal margin in order to keep within the walled-off area and to avoid opening the general peritoneal cavity. If the surgical management as outlined above of subdiaphragmatic and liver abscess is successfully carried out and supplemented with specific antibiotic coverage established by culture and sensitivity studies of the organism involved, a cure can be expected. In liver abscess, however, it is important to continue with antibiotic therapy for many months because of the tendency toward chronicity and recurrence.
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Fig. 2. Subdiaphragmatic abscess with perforation into the pleural space. (From H. D. Adams: Pleurobiliary and bronchobiliary fistulas, Journal of Thoracic Surgery 30: 255, Sept., 1955.)
Neglected or improperly managed subdiaphragmatic infection, however, may lead to perforations through the diaphragm, with widespread pleural involvement if the lung is not adherent to the diaphragm at the point of perforation (Fig. 2). If this complication does occur, immediate and adequate drainage of both the pleural cavity and the primary focus of infection beneath the diaphragm is essential. If the lung is adherent over the diaphragm, the perforation will rapidly penetrate the adjacent lung and communicate with a basal bronchus (Fig. 3). We have reported a number of cases in which a bronchobiliary fistula was produced from subdiaphragmatic collections associated with strictures of the common duct. 2 These patients required emergency drainage of the subdiaphragmatic space. This should be accomplished by the method described above and should be carried out under local anesthesia with the patient sitting up in order to prevent widespread bilateral pulmonary infection in the form of a necrotizing bronchitis and pneumonitis. Subsequent pulmonary resection may be necessary if a residual bronchiectasis develops in the segment involved in the fistulous tract.
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Fig. 3. Subdiaphragmatic abscess with perforation through the diaphragm and into the bronchus. (From H. D. Adams: Pleurobiliary and bronchobiliary fistulas, Journal of Thoracic Surgery 30: 255, Sept., 1955.)
Since we have observed that infections of this type may involve and penetrate the diaphragm, it is likewise possible for subdiaphragmatic tumors to follow the same path of extension. We have reported cases of primary carcinoma (hepatoma) of the liver which penetrated the diaphragm to involve the base of the lung. I • 3 When there is clinical and x-ray evidence of such involvement, a thoraco-abdominal approach is indicated and resection should be carried out if possible. Each case of diaphragmatic involvement or extension of infection or tumor into the thorax represents a special problem of diagnosis and special considerations anatomically of the thoraco-abdominal, cavitary and visceral relationships involved, and must be managed with considerable care and judgment. REFERENCES 1. Adams, H. D.: Intrathoracic extension of hepatic tumors. S. CLIN. NORTH AMERICA 28: 679-683 (June) 1948. 2. Adams, H. D.: Pleurobiliary and bronchobiliary fistulas. J. Thoracic Surg. 30: 255-262 (Sept.) 1955. 3. Adams, H. D.: Hepaticobiliary involvement of the thorax. S. CLIN: NORTH AMERICA 38: 611-617 (June) 1958.
ANATOMICALLY, the diaphragm acts as an effective partition between the thorax and the abdomen. We have already discussed the results of defects (herniation) in this structure but it is also important to point out that the diaphragm is not an entirely effective barrier to the extension of infection and tumor from the abdomen to the thorax. Extension of infection or tumor from the organs beneath the diaphragm, such as the liver, biliary tract, stomach or pancreas, to or through the diaphragm does occasionally occur. Liver abscess or subdiaphragmatic abscess, if not adequately drained, will perforate the diaphragm. The incidence of such abscesses has been materially reduced by the widespread use of antibiotics, although they have not been entirely eliminated by chemotherapy. In some instances the use of antibiotics has obscured the true status and progress of the abscess has led to further and more serious complications. Since these abscesses still exist, even though at present their frequency is greatly reduced, it is well to review the present status of the management and treatment of such disease processes. Infection beneath the diaphragm or in relation to the several surfaces of the liver is most commonly a postoperative complication following many types of abdominal operations. In the postoperative period, if clinical signs of obscure infection develop and when the more common sources of such infection, such as a residual abscess in the operative field, the wound, urinary tract or respiratory system, have been ruled out, attention must be focused on the subdiaphragmatic region for residual or possible extension of infection. If there has not been any antecedent abdominal operation or known source of intra-abdominal infection, a primary pyogenic abscess of the liver or a secondarily infected echinococcus or amebic abscess may involve the diaphragm. Pyogenic liver abscess or more commonly multiple liver abscesses are usually the sequelae of pyelophlebitis. With clinical signs of progressive sepsis in which the source is obscured, a focus of 847
848
HERBERT
D.
ADAMS
infection in the liver may not become apparent until signs of diaphragmatic involvement develop. Frequently it is possible to localize the infection in this general region, but the accurate differentiation from (1) basal pleural infection, (2) sUbdiaphragmatic or perihepatic infection, (3) intrahepatic or liver abscess, and (4) subhepatic, perirenal, perisplenic or pancreatic infection may be extremely difficult. The diagnosis and localization of such abscesses, however, may be accomplished by careful clinical observation, roentgenographic studies, diagnostic aspiration and, if necessary, by exploratory operation. The diagnostic procedure of greatest value is roentgenographic examination. Roentgenograms are taken with the patient in three positions: anteroposterior, sitting up; anteroposterior, lying on the side (lateral decubitus) with the affected side up, and a lateral film with the patient sitting up. These three views in these positions will frequently demonstrate a shifting collection of gas beneath the diaphragm which would be obscure in routine films taken with the patient lying on his back. Even when a shifting collection of gas cannot be demonstrated and the roentgenograms show a diaphragm elevated and obscured by a basal pleural reaction, a subphrenic abscess may still be present. Basal empyema and intrahepatic or even subhepatic abscess, such as in the bed of the gallbladder or Morison's pouch, will often give identical x-ray pictures. Localization of an abscess under the left diaphragm by roentgenography is even more difficult. Owing to the anatomical relation of the left lobe of the liver, the stomach and the spleen to the diaphragm, an abscess is more likely to dissect around or between these structures rather than to present a major part of its surface to the diaphragm, such as it does over the dome of the right lobe of the liver. As a result, little reaction may be demonstrable above the diaphragm, or the presence of a shifting collection of gas below the diaphragm may not be apparent on the roentgenogram. The most valuable diagnostic finding on the left side is an abnormal displacement or distortion of the air bubble in the fundus of the stomach. This detail should be carefully observed at fluoroscopy and the films should be taken at different angles. If a shifting gas bubble cannot be demonstrated on properly-taken films, diagnostic aspiration should be considered. In most instances the diaphragm rises high and the costophrenic pleural angles are obliterated so that aspiration is usually safe from pleural contamination. This procedure is warranted especially if the patient is extremely ill and his condition demands immediate localization of the infection and adequate surgical drainage. Another practical point with reference to diagnostic aspiration is the fact that pus, presumably obtained from the pleural cavity during thoracentesis for what appears to be a basal empyema, may actually be aspirated from beneath a high, obscure diaphragm, and an erroneous localization be assumed. If this happens the patient will invariably complain of pain at the top of his shoulder as the needle en-
Extension oj Subdiaphragmatic Disease Processes
849
counters the diaphragm. If pus is aspirated before such a diaphragmatic reference of pain is elicited, the infection is in the pleural cavity; if pus is aspirated after diaphragmatic pain is elicited, the infection is below the diaphragm. Therefore, it is essential that the surgeon be alert to this helpful localizing diagnostic sign. Finally, surgical exploration of the subphrenic region is justified in cases in which decline is rapid as a result of obscure infection and when roentgenography and attempted aspiration have failed to yield evidence for a definite diagnosis even though there is reasonably positive clinical and x-ray evidence that subdiaphragmatic infection exists. Exploration can readily be performed under local anesthesia with virtually no risk to the patient, and this may well be a life-saving measure. The surgical approach for drainage of a subdiaphragmatic abscess in the posterior inferior subphrenic space is through one of two routes. The first approach is through the bed of the resected twelfth rib i by blunt dissection retroperitoneally and extrapleurally (Fig. 1, a) the subdiaphragmatic space it involves is broken into and drained. This has the advantage of avoiding the pleura and possible contamination of this space in most cases, but has the disadvantage that a much greater amount of tissue must be traversed from this lower level to reach these invariably high collections of pus under the diaphragm and a much longer and less direct drainage tract must be maintained. In addition, it is well to remember that owing to anatomical variations the pleural reflection will be encountered as low as the twelfth rib in 30 to 40 per cent of the cases. Therefore, we favor the second, more direct route at a higher level, electively crossing the lower costophrenic reflections of the pleura. A posterior segment of the eleventh rib is resected and a corresponding length of its intercostal bundle removed to enlarge the exposed surface of the parietal pleura. Care must be taken at this point not to open the pleura to avoid contamination and pneumothorax. If the costophrenic pleural reflection has not been obliterated by the inflammatory process, which can readily be determined by the appearance of the pleura and observing the two surfaces sliding free on each other or being held apart by fluid, one of two methods of obliterating the costopleural angle must be carried out. A firm gauze pack placed against the exposed parietal pleura and left in place for 48 hours will effectively seal off the pleura. This has the distinct disadvantage of requiring a two stage procedure with several days' delay before the final drainage is accomplished and the patient relieved of marked signs of infection. If the time element because of the patient's condition is important-which is usually the case-the costophrenic pleural surfaces can be sutured together with fine interrupted sutures placed around the entire periphery of the exposed pleura (Fig. 1, b); the pleura and diaphragm beneath it are opened directly into the abscess by an incision in the center of this isolated
850
HERBERT
D.
ADAMS
Fig. 1. a, Drainage of a subdiaphragmatic abscess in bed of the eleventh rib. b, Method of obliterating the costophrenic pleural reflection.
section of parietal and diaphragmatic pleura without fear of contamination of the pleural cavity. The abscess can readily be reached through this approach and excellent and direct drainage obtained. The drainage is maintained by inserting a soft rubber chest tube or cigarette drain with a small catheter for irrigation and instillation of the proper antibiotic agent. Anterior space and subhepatic infections can be drained satisfactorily through a subcostal incision several inches to the right of the xiphoid process, carrying the dissection upward close to the under surface of the costal margin in order to keep within the walled-off area and to avoid opening the general peritoneal cavity. If the surgical management as outlined above of subdiaphragmatic and liver abscess is successfully carried out and supplemented with specific antibiotic coverage established by culture and sensitivity studies of the organism involved, a cure can be expected. In liver abscess, however, it is important to continue with antibiotic therapy for many months because of the tendency toward chronicity and recurrence.
Extension of Subdiaphragmatic Disease Processes
851
Fig. 2. Subdiaphragmatic abscess with perforation into the pleural space. (From H. D. Adams: Pleurobiliary and bronchobiliary fistulas, Journal of Thoracic Surgery 30: 255, Sept., 1955.)
Neglected or improperly managed subdiaphragmatic infection, however, may lead to perforations through the diaphragm, with widespread pleural involvement if the lung is not adherent to the diaphragm at the point of perforation (Fig. 2). If this complication does occur, immediate and adequate drainage of both the pleural cavity and the primary focus of infection beneath the diaphragm is essential. If the lung is adherent over the diaphragm, the perforation will rapidly penetrate the adjacent lung and communicate with a basal bronchus (Fig. 3). We have reported a number of cases in which a bronchobiliary fistula was produced from subdiaphragmatic collections associated with strictures of the common duct. 2 These patients required emergency drainage of the subdiaphragmatic space. This should be accomplished by the method described above and should be carried out under local anesthesia with the patient sitting up in order to prevent widespread bilateral pulmonary infection in the form of a necrotizing bronchitis and pneumonitis. Subsequent pulmonary resection may be necessary if a residual bronchiectasis develops in the segment involved in the fistulous tract.
852
HERBERT
D.
ADAMS
Fig. 3. Subdiaphragmatic abscess with perforation through the diaphragm and into the bronchus. (From H. D. Adams: Pleurobiliary and bronchobiliary fistulas, Journal of Thoracic Surgery 30: 255, Sept., 1955.)
Since we have observed that infections of this type may involve and penetrate the diaphragm, it is likewise possible for subdiaphragmatic tumors to follow the same path of extension. We have reported cases of primary carcinoma (hepatoma) of the liver which penetrated the diaphragm to involve the base of the lung. I • 3 When there is clinical and x-ray evidence of such involvement, a thoraco-abdominal approach is indicated and resection should be carried out if possible. Each case of diaphragmatic involvement or extension of infection or tumor into the thorax represents a special problem of diagnosis and special considerations anatomically of the thoraco-abdominal, cavitary and visceral relationships involved, and must be managed with considerable care and judgment. REFERENCES 1. Adams, H. D.: Intrathoracic extension of hepatic tumors. S. CLIN. NORTH AMERICA 28: 679-683 (June) 1948. 2. Adams, H. D.: Pleurobiliary and bronchobiliary fistulas. J. Thoracic Surg. 30: 255-262 (Sept.) 1955. 3. Adams, H. D.: Hepaticobiliary involvement of the thorax. S. CLIN: NORTH AMERICA 38: 611-617 (June) 1958.