- Email: [email protected]
Postoperative Obstruction and Ileus
Postoperative Obstruction and Ileus BENTLEY P. COI;COCK
THE danger of postoperative obstruction of the gastrointestinal tract is inherent in every laparotomy. Nausea or vomiting associated with some abdominal pain, or slight distention of the abdomen, poses a most disturbing problem in any patient who has had an abdominal operation. It may simply indicate mild postoperative ileus of the stomach and bowel. It can be the first indication of a marked gastric dilatation which will be followed by signs and symptoms of shock. It may be due to kinking of a loop of small intestine with the onset of partial obstruction. The surgeon knows that if this partial obstruction is not relieved it may progress rapidly to complete obstruction which will require another operation. It may be even more serious and represent the first sign of small bowel obstruction associated with strangulation. In such instances, even a few hours' delay in reoperating on the patient can result in a fatality. Few postoperative complications make a greater demand on the judgment of the surgeon than obstruction following an abdominal operation. Every piece of evidence for or against this diagnosis must be carefully noted and evaluated. Frequently, the patient's life will depend upon the accuracy of the surgeon's decision in regard to the complication within the abdomen and the promptness and manner with which he corrects the situation.
GENERAL CONSIDERATIONS
The surgeon must be alert for the development of obstruction in patients who have had more than one laparotomy. In such cases obstruction is particularly likely to occur if there has been a previous operation for intestinal obstruction, or if many adhesions were found at the time of the recent operative procedure. An inflammatory process such as that surrounding a perforated carcinoma of the stomach or colon predisposes the patient to the development of inflammatory adhesions of the small intestine which may give rise to obstruction during the postoperative course. Patients in whom it has not been possible to reperitonealize the operative field should be carefully watched for the development of postoperative obstruction. It is in this group of patients that subsequent obstruction of the small intestine may be prevented by the introduction 719
Bentley P. Colcock
720
of a Miller-Abbott or Harris tube well down into the small intestine either before or during the operative procedure. Unfortunately, none of the many substances that have been recommended for the prevention of postoperative obstruction has stood the test of time. Drugs such as prostigmin are useful in promoting the early return of peristalsis following the relief of the obstruction by operation. They have no place in the treatment of unrelieved postoperative obstruction. There is no evidence that their routine use following abdominal laparotomy will prevent obstruction. The avoidance of soiling of the peritoneal surface during the operative procedure, the reperitonealization of all raw surfaces whenever possible, and the intubation of the small bowel are the measures that must be depended upon to prevent postoperative intestinal obstruction. SIGNS AND SYMPTOMS
Pain. Some degree of pain is present following every laparotomy. An increase in that pain on the second, third or fourth postoperative day is significant and may represent the onset of an intra-abdominal complication such as obstruction. Obstruction should be suspected particularly if the pain is cramplike in nature and tends to increase in severity. if the obstruction is associated with incarceration, the pain may become steady and localized to a definite area of the abdomen. If these findings are associated with localized tenderness, strangulation with early peritonitis may be present. Nausea and Vomiting. Some degree of gastric dilatation and retention is so common after major abdominal procedures that at the first indication of nausea or vomiting a tube should be introduced into the stomach if one is not already in place. The character and the amount of the gastric drainage will help to determine whether the nausea or vomiting is due to simple gastric dilatation or to obstruction of the small intestine. Distention. Generalized abdominal distention may indicate simple ileus of the small bowel or it may be due to a mechanical obstruction of the distal jejunum, ileum or colon. The absence of distention does not rule out obstruction of the small bowel, for a patient may have a complete block of a high jejunal loop with little or no abdominal distention. Peristalsis. Frequently, valuable information can be obtained by auscultation of the abdomen. Normal peristalsis is evidence against small bowel obstruction, although peristalsis may be present in the lower part of the abdomen if the obstruction is high in the jejunum. Hyperactive, high-pitched sounds are frequently associated with mechanical obstruction of the small bowel. The absence of peristalsis may indicate simple postoperative ileus or it may mean ileus secondary to peritonitis. ::Fever and Leukocytosis. These will not be helpful early in the postoperative period when some degree of elevated temperature and increased
Postoperative Obstruction and Ileus
721
white cell count may be present as a result of the operative procedure itself. An increase in fever or in the white blood cell count indicates an inflammatory reaction such as that associated with an ileus secondary to peritonitis or obstruction due to a strangulated loop of small bowel. ROENTGENOLOGIC EXAMINATION
A roentgenogram of the abdomen may be most helpful in establishing the diagnosis of postoperative obstruction when the diagnosis is indefinite. The presence of gas-filled loops of small intestine, particularly when associated with fluid levels shown on the upright film, is typical of obstruction of the small intestine. Moderate distention of small intestinal loops with absence of gas in the colon is suggestive of early obstruction of the small bowel. The possibility of incarceration and strangulation is increased if there is marked localized distention of one or two loops of small intestine. Marked distention of the entire colon, particularly of the cecum, is found in obstruction of the distal colon and may be followed by perforation of the cecum if it is not corrected. OBSTRUCTION AFTER OPERATIVE PROCEDURES ON THE GASTROINTESTINAL TRACT
The physician must be particularly alert for development of obstruction in patients who have had operative procedures on the stomach, small intestine or colon. The nature of the pathologic changes present, or the type of operative procedure that has been carried out will suggest definite possibilities, each of which must be carefully considered. Any operative procedure in which an anastomosis has been made between a portion of the stomach and the duodenum or jejunum may be followed by obstruction at the site of the anastomosis. This is characterized by prolonged drainage of large amounts of gastric fluid following intubation of the stomach. Pain and any distention which might have been present should be promptly relieved by a tube introduced through the nose into the stomach. Peristaltic sounds will be normal, and a roentgenogram of the abdomen shows no distention of the small bowel. The possibility of a high jejunal obstruction which may occur following subtotal gastrectomy and gastrojejunostomy must also be kept in mind. The distended jejunal loop may be demonstrated by a flat film of the abdomen. This complication may be association with the rapid onset , of strangulation of the jejunum and perforation. * If this is not promptly relieved by intubation or if signs of peritoneal irritation develop, immediate operation is imperative. Pathologic conditions of the small intestine such as multiple adhesions, or an acute inflammatory condition such as regional ileitis, may result in postoperative obstruction. It is in such cases that the introduction of a * Colcock, B. P.: Internal herniation following subtotal gastrectomy. Lahey Clin. Bull. 8: 233-237 (Apr.) 1956.
722
Bentley P. Colcock
long intestinal tube into the small bowel either before or during the operative procedure may splint the bowel sufficiently to prevent acute angulation and obstruction. Following resection of the small bowel, I prefer an end-to-end anastomosis, but postoperative obstruction at the site of the anastomosis may occur unless the surgeon is careful not to produce excessive inversion at the suture line. Suction through a long intestinal tube will keep the proximal segment of small bowel decompressed until the anastomosis is functioning. For the same reason I intubate the small intestine before resecting the right colon for carcinoma. With a tube well down into the jejunum or ileum, the area of the anastomosis between the terminal ileum and transverse colon can be decompressed until nor~al peristalsis and the passage of gas by rectum indicate that the anastomosis is functioning normally. The use of interrupted sutures and the inversion of a minimal amount of tissue will lessen the danger of postoperative obstruction at the anastomosis following resection of the colon. Division of the bowel with a knife rather than with the cautery, and the excision of all tissue crushed by the clamps will permit minimal inversion of the bowel wall at the site of the anastomosis. This is particularly important following resection of the sigmoid colon when the relatively narrow descending colon has been anastomosed to the rectum. Obstruction of the colon is characterized by increasing abdominal discomfort and distention. Nausea and vomiting may be completely absent in the early stages. If the ileocecal valve remains competent, marked distention of the colon may occur even to the point of perforation of the cecum before the small bowel becomes distended. A roentgenogram of the abdomen will establish the diagnosis and reveal the degree of distention of the cecum and colon. A barium enema examination will determine the exact point of the obstruction and often will indicate its nature. OBSTRUCTION FOLLOWING OPERATIONS ON THE RECTUM
In addition to the possibility of small bowel obstruction, which may follow any laparotomy, patients who have had an abdominoperineal resection for cancer of the rectum occasionally develop obstruction from herniation of a loop of small bowel through the newly reconstructed pelvic floor or from herniation of the small bowel along the left lumbar gutter lateral to the colostomy. Adequate mobilization of the peritoneum from the surface of the bladder and from the lateral pelvic walls will permit the construction of an intact, though relaxed, pelvic floor. The left lumbar gutter can be closed by suture of the peritoneum of the mesentery of the terminal colon to the lateral parietal peritoneum up to the laparotomy incision. It should be emphasized that if this is done it must be done carefully and well, otherwise a relatively large aperture may be converted into a small one and the danger of a strangulating obstruction of the small bowel will be increased.
Postoperative Obstruction and Ileus
723
TREATMENT
Fluids. A daily fluid balance chart is an essential part of the care of any patient with postoperative obstruction. An indwelling bladder catheter is necessary to determine accurately the amount of urine excreted in 24 hours. Accurate measurement of the amount of fluid withdrawn by nasal suction is also essential in determining fluid replacement. Fluid and electrolyte replacement in these patients forms a vital part of their treatment throughout the course of their complication whether they require reoperation or are treated by intubation. It should be under the care of one individual and the needs of each patient should be re-evaluated daily. Intubation. If the stomach has been intubated either before or during the operative procedure the tube should be irrigated at regular intervals to make certain that 'it is patent. If an indwelling tube is not already in place, it should be introduced promptly if the patient complains of epigastric fullness, distress or nausea. Gastric dilatation may have an insidious onset, with symptoms of shock being the first obvious indication of its presence. Obstruction at the gastrojejunal anastomosis is rare and when it does occur is usually due to edema. Decompression of the stomach over a period of days will control this situation until the edema subsides and the gastric contents empty spontaneously into the jejunum. A long intestinal tube, such as the Miller-Abbott tube, should be introduced promptly in any patient with small bowel obstruction. This can usually be accomplished within 24 to 36 hours by the use of mercury in the balloon plus correct alignment of the tube under fluoroscopic guidance. Intubation should be carried out for any patient with generalized ileus of the small bowel due either to the operative procedure or to peritonitis. Intubation of the small intestine cannot be depended upon to decompress a markedly distended colon. If the tube cannot be introduced into the small intestine or if the signs and symptoms of obstruction persist despite introduction of the tube, immediate operation should be considered. Operation must be carried out promptly if there is any evidence of peritoneal irritation with a mechanically obstructed bowel, for this probably indicates strangulation. OPERATION
Although use of the long intestinal tube, such as the Miller-Abbott or Harris tube, combined with Wangensteen suction represents a tremendous advance in the treatment of postoperative obstruction, its misuse carries a very grave risk. Any patient in whom there is reason to suspect possible strangulation should of course be operated on immediately. Even in the absence of signs or symptoms of strangulation, if intubation of the small bowel fails to relieve the symptoms within a reasonable period of time, operation should be performed. What constitutes a reasonable period of time will depend upon a number of factors such as
724
Bentley P. Colcock
the progress of the tube through the stomach into the small intestine, the type and severity of the patient's symptoms, and particularly, whether or not progress is being made in relieving the obstruction. In operating for postoperative obstruction, the surgeon rarely has reason to feel that the operation was unnecessary. He is much more likely to wish that he had operated earlier.
THE danger of postoperative obstruction of the gastrointestinal tract is inherent in every laparotomy. Nausea or vomiting associated with some abdominal pain, or slight distention of the abdomen, poses a most disturbing problem in any patient who has had an abdominal operation. It may simply indicate mild postoperative ileus of the stomach and bowel. It can be the first indication of a marked gastric dilatation which will be followed by signs and symptoms of shock. It may be due to kinking of a loop of small intestine with the onset of partial obstruction. The surgeon knows that if this partial obstruction is not relieved it may progress rapidly to complete obstruction which will require another operation. It may be even more serious and represent the first sign of small bowel obstruction associated with strangulation. In such instances, even a few hours' delay in reoperating on the patient can result in a fatality. Few postoperative complications make a greater demand on the judgment of the surgeon than obstruction following an abdominal operation. Every piece of evidence for or against this diagnosis must be carefully noted and evaluated. Frequently, the patient's life will depend upon the accuracy of the surgeon's decision in regard to the complication within the abdomen and the promptness and manner with which he corrects the situation.
GENERAL CONSIDERATIONS
The surgeon must be alert for the development of obstruction in patients who have had more than one laparotomy. In such cases obstruction is particularly likely to occur if there has been a previous operation for intestinal obstruction, or if many adhesions were found at the time of the recent operative procedure. An inflammatory process such as that surrounding a perforated carcinoma of the stomach or colon predisposes the patient to the development of inflammatory adhesions of the small intestine which may give rise to obstruction during the postoperative course. Patients in whom it has not been possible to reperitonealize the operative field should be carefully watched for the development of postoperative obstruction. It is in this group of patients that subsequent obstruction of the small intestine may be prevented by the introduction 719
Bentley P. Colcock
720
of a Miller-Abbott or Harris tube well down into the small intestine either before or during the operative procedure. Unfortunately, none of the many substances that have been recommended for the prevention of postoperative obstruction has stood the test of time. Drugs such as prostigmin are useful in promoting the early return of peristalsis following the relief of the obstruction by operation. They have no place in the treatment of unrelieved postoperative obstruction. There is no evidence that their routine use following abdominal laparotomy will prevent obstruction. The avoidance of soiling of the peritoneal surface during the operative procedure, the reperitonealization of all raw surfaces whenever possible, and the intubation of the small bowel are the measures that must be depended upon to prevent postoperative intestinal obstruction. SIGNS AND SYMPTOMS
Pain. Some degree of pain is present following every laparotomy. An increase in that pain on the second, third or fourth postoperative day is significant and may represent the onset of an intra-abdominal complication such as obstruction. Obstruction should be suspected particularly if the pain is cramplike in nature and tends to increase in severity. if the obstruction is associated with incarceration, the pain may become steady and localized to a definite area of the abdomen. If these findings are associated with localized tenderness, strangulation with early peritonitis may be present. Nausea and Vomiting. Some degree of gastric dilatation and retention is so common after major abdominal procedures that at the first indication of nausea or vomiting a tube should be introduced into the stomach if one is not already in place. The character and the amount of the gastric drainage will help to determine whether the nausea or vomiting is due to simple gastric dilatation or to obstruction of the small intestine. Distention. Generalized abdominal distention may indicate simple ileus of the small bowel or it may be due to a mechanical obstruction of the distal jejunum, ileum or colon. The absence of distention does not rule out obstruction of the small bowel, for a patient may have a complete block of a high jejunal loop with little or no abdominal distention. Peristalsis. Frequently, valuable information can be obtained by auscultation of the abdomen. Normal peristalsis is evidence against small bowel obstruction, although peristalsis may be present in the lower part of the abdomen if the obstruction is high in the jejunum. Hyperactive, high-pitched sounds are frequently associated with mechanical obstruction of the small bowel. The absence of peristalsis may indicate simple postoperative ileus or it may mean ileus secondary to peritonitis. ::Fever and Leukocytosis. These will not be helpful early in the postoperative period when some degree of elevated temperature and increased
Postoperative Obstruction and Ileus
721
white cell count may be present as a result of the operative procedure itself. An increase in fever or in the white blood cell count indicates an inflammatory reaction such as that associated with an ileus secondary to peritonitis or obstruction due to a strangulated loop of small bowel. ROENTGENOLOGIC EXAMINATION
A roentgenogram of the abdomen may be most helpful in establishing the diagnosis of postoperative obstruction when the diagnosis is indefinite. The presence of gas-filled loops of small intestine, particularly when associated with fluid levels shown on the upright film, is typical of obstruction of the small intestine. Moderate distention of small intestinal loops with absence of gas in the colon is suggestive of early obstruction of the small bowel. The possibility of incarceration and strangulation is increased if there is marked localized distention of one or two loops of small intestine. Marked distention of the entire colon, particularly of the cecum, is found in obstruction of the distal colon and may be followed by perforation of the cecum if it is not corrected. OBSTRUCTION AFTER OPERATIVE PROCEDURES ON THE GASTROINTESTINAL TRACT
The physician must be particularly alert for development of obstruction in patients who have had operative procedures on the stomach, small intestine or colon. The nature of the pathologic changes present, or the type of operative procedure that has been carried out will suggest definite possibilities, each of which must be carefully considered. Any operative procedure in which an anastomosis has been made between a portion of the stomach and the duodenum or jejunum may be followed by obstruction at the site of the anastomosis. This is characterized by prolonged drainage of large amounts of gastric fluid following intubation of the stomach. Pain and any distention which might have been present should be promptly relieved by a tube introduced through the nose into the stomach. Peristaltic sounds will be normal, and a roentgenogram of the abdomen shows no distention of the small bowel. The possibility of a high jejunal obstruction which may occur following subtotal gastrectomy and gastrojejunostomy must also be kept in mind. The distended jejunal loop may be demonstrated by a flat film of the abdomen. This complication may be association with the rapid onset , of strangulation of the jejunum and perforation. * If this is not promptly relieved by intubation or if signs of peritoneal irritation develop, immediate operation is imperative. Pathologic conditions of the small intestine such as multiple adhesions, or an acute inflammatory condition such as regional ileitis, may result in postoperative obstruction. It is in such cases that the introduction of a * Colcock, B. P.: Internal herniation following subtotal gastrectomy. Lahey Clin. Bull. 8: 233-237 (Apr.) 1956.
722
Bentley P. Colcock
long intestinal tube into the small bowel either before or during the operative procedure may splint the bowel sufficiently to prevent acute angulation and obstruction. Following resection of the small bowel, I prefer an end-to-end anastomosis, but postoperative obstruction at the site of the anastomosis may occur unless the surgeon is careful not to produce excessive inversion at the suture line. Suction through a long intestinal tube will keep the proximal segment of small bowel decompressed until the anastomosis is functioning. For the same reason I intubate the small intestine before resecting the right colon for carcinoma. With a tube well down into the jejunum or ileum, the area of the anastomosis between the terminal ileum and transverse colon can be decompressed until nor~al peristalsis and the passage of gas by rectum indicate that the anastomosis is functioning normally. The use of interrupted sutures and the inversion of a minimal amount of tissue will lessen the danger of postoperative obstruction at the anastomosis following resection of the colon. Division of the bowel with a knife rather than with the cautery, and the excision of all tissue crushed by the clamps will permit minimal inversion of the bowel wall at the site of the anastomosis. This is particularly important following resection of the sigmoid colon when the relatively narrow descending colon has been anastomosed to the rectum. Obstruction of the colon is characterized by increasing abdominal discomfort and distention. Nausea and vomiting may be completely absent in the early stages. If the ileocecal valve remains competent, marked distention of the colon may occur even to the point of perforation of the cecum before the small bowel becomes distended. A roentgenogram of the abdomen will establish the diagnosis and reveal the degree of distention of the cecum and colon. A barium enema examination will determine the exact point of the obstruction and often will indicate its nature. OBSTRUCTION FOLLOWING OPERATIONS ON THE RECTUM
In addition to the possibility of small bowel obstruction, which may follow any laparotomy, patients who have had an abdominoperineal resection for cancer of the rectum occasionally develop obstruction from herniation of a loop of small bowel through the newly reconstructed pelvic floor or from herniation of the small bowel along the left lumbar gutter lateral to the colostomy. Adequate mobilization of the peritoneum from the surface of the bladder and from the lateral pelvic walls will permit the construction of an intact, though relaxed, pelvic floor. The left lumbar gutter can be closed by suture of the peritoneum of the mesentery of the terminal colon to the lateral parietal peritoneum up to the laparotomy incision. It should be emphasized that if this is done it must be done carefully and well, otherwise a relatively large aperture may be converted into a small one and the danger of a strangulating obstruction of the small bowel will be increased.
Postoperative Obstruction and Ileus
723
TREATMENT
Fluids. A daily fluid balance chart is an essential part of the care of any patient with postoperative obstruction. An indwelling bladder catheter is necessary to determine accurately the amount of urine excreted in 24 hours. Accurate measurement of the amount of fluid withdrawn by nasal suction is also essential in determining fluid replacement. Fluid and electrolyte replacement in these patients forms a vital part of their treatment throughout the course of their complication whether they require reoperation or are treated by intubation. It should be under the care of one individual and the needs of each patient should be re-evaluated daily. Intubation. If the stomach has been intubated either before or during the operative procedure the tube should be irrigated at regular intervals to make certain that 'it is patent. If an indwelling tube is not already in place, it should be introduced promptly if the patient complains of epigastric fullness, distress or nausea. Gastric dilatation may have an insidious onset, with symptoms of shock being the first obvious indication of its presence. Obstruction at the gastrojejunal anastomosis is rare and when it does occur is usually due to edema. Decompression of the stomach over a period of days will control this situation until the edema subsides and the gastric contents empty spontaneously into the jejunum. A long intestinal tube, such as the Miller-Abbott tube, should be introduced promptly in any patient with small bowel obstruction. This can usually be accomplished within 24 to 36 hours by the use of mercury in the balloon plus correct alignment of the tube under fluoroscopic guidance. Intubation should be carried out for any patient with generalized ileus of the small bowel due either to the operative procedure or to peritonitis. Intubation of the small intestine cannot be depended upon to decompress a markedly distended colon. If the tube cannot be introduced into the small intestine or if the signs and symptoms of obstruction persist despite introduction of the tube, immediate operation should be considered. Operation must be carried out promptly if there is any evidence of peritoneal irritation with a mechanically obstructed bowel, for this probably indicates strangulation. OPERATION
Although use of the long intestinal tube, such as the Miller-Abbott or Harris tube, combined with Wangensteen suction represents a tremendous advance in the treatment of postoperative obstruction, its misuse carries a very grave risk. Any patient in whom there is reason to suspect possible strangulation should of course be operated on immediately. Even in the absence of signs or symptoms of strangulation, if intubation of the small bowel fails to relieve the symptoms within a reasonable period of time, operation should be performed. What constitutes a reasonable period of time will depend upon a number of factors such as
724
Bentley P. Colcock
the progress of the tube through the stomach into the small intestine, the type and severity of the patient's symptoms, and particularly, whether or not progress is being made in relieving the obstruction. In operating for postoperative obstruction, the surgeon rarely has reason to feel that the operation was unnecessary. He is much more likely to wish that he had operated earlier.