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Diaphragmatic Hernia in Infancy and Childhood
Diaphragmatic Hernia in Infancy and Childhood STUART A. THOMSON, M.D.*
THE outward obscurity of the diaphragm contributes to the delay and difficulty in diagnosing congenital and traumatic herniae. Congenital diaphragmatic hernia is an uncommon condition which has been emphasized repeatedly in the literature. Until about fifteen years ago the operative mortality in the first year of life was close to 50 per cent. In 1942 Stuart Harrington reported a series of 304 cases of diaphragmatic hernia of which 21 were in children 12 years of age or less. There were 4 deaths in the 21 children operated upon. According to Harrington, the various types of diaphragmatic hernia have the following order of incidence: ADULTS
1. 2. 3. 4.
Oesophageal hiatus Traumatic Subcostosternal Pleuroperitoneal
CHILDREN
1. Pleuroperitoneal 2. Congenital absence of posterior third 3. Oesophageal hiatus 4. Traumatic
The commonest childhood hernia of the diaphragm, the pleuroperitoneal, is an infrequent finding in adults because over 75 per cent of the children suffering from it die if not operated upon before they are a year old. This high mortality in the unoperated cases is due to the fact that the newborn child has not developed a sufficient degree of compensatory cardiac or respiratory reserve to maintain function. Therefore, in an infant with cardiac or respiratory difficulty, the thorax should be examined and x-rayed immediately. Since this type of congenital hernia is recognizable at birth and is a threatening menace to life, immediate operative repair should be carried out. EMBRYOLOGY OF THE DIAPHRAGM
The diaphragm is one of the most complex structures of the body from the standpoint of development. It first appears in the cervical region as * Attending Surgeon, Hospital for Sick Children; Associate in Surgery, University of Toronto, Toronto, Ontario, Canada. 997
998
Stuart A. Thomson
the septum transversum in the first month of fetal life. It immediately begins a rapid descent and is followed by the stomach and elongating oesophagus. During this phase there is a continuous canal behind the septum transversum which connects the pleural and peritoneal coeloms. This dorsal canal is divided in two by the developing dorsal mesentery which includes the oesophagus and stomach. The two canals are then called the pleuroperitoneal canals. During the second intrauterine month the pleuroperitoneal canals are closed by proliferation of the dorsal mesentery and the Wolffian ridge. This is what Dunhill speaks of as the "membranous stage" because the diaphragm is now a complete membrane and a hernia developing at this stage will be a true one with a sac. During the third fetal month a muscle mass followed by the phrenic nerve invades the membranous diaphragm. The posterior part and finally the crus are the last to be transformed into muscle and hence most of the congenital defects occur in these areas. Although the embryology of the diaphragm is very complex, a little knowledge of it helps to explain why some herniae have no sac and others do and again why a large portion of the diaphragm may be absent. The fact that the phrenic nerve is the sole motor supply of the diaphragm seems to make its complex origin doubtful, but this is counteracted by the fact that the muscle mass with its nerve appears after the membranous diaphragm is formed. It would be strange if a structure as complicated in its origin as the diaphragm did not sometimes fail to develop perfectly. It is not surprising that fusion occasionally is less than perfect. The strains to which the diaphragm is subjected in early life are likely to manifest any weakness. ANATOMY
The normally developed diaphragm is a musculo-aponeurotic partition between the thorax and abdomen. It is attached on each side by fleshy digitations to the back of the xiphoid process and the inner surfaces of the lower six costal cartilages and posteriorly from the vertebral column and lumbocostal arches. The vertebral attachments constitute the crura which unite in the midline in front of the aorta. Muscular deficiencies on each side of the xiphoid attachment are filled with areolar tissue and covered ",ith pleura and peritoneum. The superior deep epigastric vessels pass through this space. They are known as the foramina of Morgagni. The aorta passes behind rather than through the diaphragm. The oesophagus passes through an arbour of decussating muscle fibres whereas the caval opening is in the tendinous portion. PATHOLOGY
From the foregoing brief notes on embryology it becomes evident that a hernia will not have a sac if it develops before the end of the second fetal
Diaphragmatic Hernia in Infancy and Childhood
999
month. If development is normal to the second fetal month, then the membranous diaphragm is complete and a subsequent· hernia will have a sac. Herniation through the left diaphragm is four to six times more frequent than through the right side. Massive protection is given to the right side by the right lobe of the liver. Furthermore, the structures in the left hypochondrium are very mobile and thus afford a ready phalanx for a breach. However, exactly the same defects may be found in the right side as are found in the left diaphragm, though o(course the invading structures will differ.
Fig. 254.
Fig. 255.
Fig. 254. Absent posterior third, right diaphragm and most likely the left third as well. Thick pleural sac filled with mediastinal connective tissue and stomach. Fig. 255. Anteroposterior view showing bilateral subcostosternal defect containing transverse colon.
Some of the congenital herniae behave not unlike the acquired adult hernia of the oesophageal hiatus type, as for example, where there was a failure of development of the crural part of the diaphragm (Fig. 254). Here (as in the hiatus cases) the fundus of the stomach had behaved as a sliding hernia and passed up into the posterior mediastinum and then bulged into the right pleural cavity. In the more advanced stage of this type the stomach drags after it the transverse colon, omentum and occasionally the spleen. In our series, the true or sacculated herniae were limited to the cases of congenital absence of the posterior part. The right-sided herniae usually contain stomach, as noted above, or transverse colon, as in the case of the subcostosternal defects (Fig. 255). However, a typical triangular-shaped defect in the posterior leaf of the.
Stuart A. Thomson
1000
right diaphragm may contain all the ileum, caecum, ascending and part of the transverse colon (Fig. 256). Of interest is the fact that bilateral herniation may occur with a large substernal defect (Fig. 255). Herniae through the left leaf of the diaphragm commonly contain varying amounts of small bowel and occasionally all of it (Fig. 257). Adhesions are not common but may occur between the margins of the hernia and the viscera, and occasionally between bowel and lung. In
Fig. 256. Right-sided pleuroperitoneal defect containing most of the ileum, caecum, ascending and part of the transverse colon.
the presence of one congenital anomaly others are liable to occur, such as failure to complete rotation of large bowel. There may also be malformation of the mesentery of both large and small bowel. Awareness of these various pathological states will help in the choice of the surgical approach for repair. SIGNS AND SYMPTOMS
Diaphragmatic hernia in infancy may be confused with any other condition which produces cyanosis, such as cerebral haemorrhage, congenital heart disease, and tracheo-oesophageal fistula. It is important to have the chest examined and to make a flat x-ray plate, because most
Diaphragmatic Hernia in Infancy and Childhood
1001
children with hernia, without a sac, die in the first few hours of life from cardiorespiratory embarrassment. Later in life the symptoms may become quite complex owing to the changeable contents of the hernia with various body positions, and also owing to the health of those viscera within the hernia. An oesophageal hiatus hernia with only part of the fundus of the stomach involved may give rise to more symptoms than a congenital hernia with the entire
Fig. 257.
Fig. 258.
Fig. 257. Left-sided pleuroperitoneal defect through which had passed all the small bowel, filling the entire pleural cavity. Mediastinum and heart appear to be occupying the right pleural cavity. Fig. 258. Same case two weeks after operation shows expansion of left lung and normal restoration of heart and mediastinum.
pleural cavity full of abdominal viscera. Thus, as Harrington has stated, the condition may be termed "the masquerader of the upper abdomen." On the other hand, the symptoms may be quite latent, as in one case where an accident revealed the presence of a congenital defect in the left diaphragm with a recent additional tear (Fig. 259). Intestinal obstruction may occur due to constriction at the neck of the hernia, and occasionally due to adhesions. DIAGNOSIS
For the infant, struggling for its life, a thin barium meal is unnecessary and probably dangerous. For the older patients with occasional
Stuart A. Thomson
1002
bouts of dyspnoea, cyanosis or vomiting, a barium meal is a helpful adjunct to clinical examination and fiat x-ray of the chest. The type of hernia can usually be diagnosed and often the shadow of a sac is seen (Fig. 254). X-rays taken in both horizontal and upright positions help to tell how mobile the hernial contents may be. Anteroposterior and lateral views readily differentiate the substernal type from the posterior group. Dextrocardia may be considered in the diagnosis (Fig. 257). Mediastinal cyst can be a confusing possibility, unless a barium meal is given.
Fig. 259.
Fig. 260.
Fig. 259. Left-sided pleuroperitoneal defect with added traumatic tear. Fig. 260. Same patient one month after operation.
A careful physical examination will usually lead to the correct diagnosis. The important chest findings are tympany, borborygmi, shift of the mediastinum, and distant breath sounds. In the past thirty-two years 39 cases have been found in the Hospital for Sick Children. The ages of the patients ranged from 3 hours to llYz years. Twenty-seven of these were admitted in the last thirteen years and operated upon. TREATMENT
From a review of Table 1 it is obvious that there is nothing to recommend the nonoperative or even delayed treatment of congenital diaphragmatic hernia. In the nonoperative cases there was a mortality of 66.6 per cent with all but one patient dying before 2 months of age. The cases in Table 1 occurred prior to fifteen years ago. Of the 30 patients operated upon, 10 died. In an earlier report of
1003
Diaphragmatic Hernia in Infancy and Childhood
cases seen prior to the end of 1946, 14 patients had been operated upon with only 2 deaths, a mortality of 14.2 per cent. In the last seven years 16 patients have been operated upon with a mortality of 50 per cent. As far as one can determine this recent increase in mortality rate is due to several factors, as follows: (1) Greater awareness of this anomaly and earlier diagnosis. As a Table 1 NON OPERATIVE CASES (Age 6 days to 1172 years) Site of hernia Pleuroperitoneal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Subcostosternal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Congenital absence of posterior third (left) ................ Oesophageal hiatus (left) ................................ TOTAL .................................................. Result Death before 2 months of age ............................. Death at 8 months of age ......................... ········ Apparently alive but could not be traced ..................
6 1 1 1 9 5 1 3
TOTAL .................................................. 9 Table 2
OPERATIVE CASES (Age 3 hours to 1172 years) SITE OF HERNIA
NO. OF CASES
Pleuroperitoneal (none with sac) ..................... ..
17
Congenital absence of posteterior third (all with sac except 3) ..................
9
Foramen of Morgagni ....... Traumatic .................. Para-oesophageal ............ TOTAL ....................
REMARKS
fl
right-sided
RESULT
6 deaths
(I partially traumatic
f7
left
4 deaths
(I right 1 2
1
Bilateral Left-sided Left-sided
- - - - - ---------,---- -----30
result, in these last 16 cases all but 4 patients were under 10 days of age. In this age group diaphragmatic hernia is often attended with other complications and is the greatest challenge. (2) Congenital atelectasis with inability to expand the lung at operation. (3) A wider surgical interest has been attracted so that in this group a larger number of surgeons performed the operation for the first time. Also a much larger number of anaesthetists participatecl, using more varied anaesthetic agents. .
1004-
Stuart A. Thomson
In the past fifteen years, most of the defects in the diaphragm have been repaired with interrupted heavy silk (00 Deknatal). The edges have been slightly overlapped without scarifying so as to allow a double closure. Phrenic nerve crush has not been found necessary in the past ten years. The abdominal approach is best for all left-sided herniae and probably best for most right-sided ones. When using the abdominal approach a long paramedian rectus muscle-splitting incision is made. A high kidney
rest or bolster under the 12th rib offers an excellent exposure (Fig. 261). After reduction and repair of the hernia, the kidney rest is lowered and the abdomen is repaired. A secure closure is best accomplished with stainless steel figure-of-8 buried sutures. This precludes any risk of eventration, makes the nursing care easier and increases the comfort of the patient. Preoperative and postoperative gastric suction for several days is essential. Intratracheal ether anaesthesia is by far the safest and best agent. This anaesthetic may be carried to an apnoeic stage with controlled respirations if necessary. If this does not produce satisfactory relaxation the addition of succinylcholine yvill help. It is a new shorter-acting drug
Diaphragmatic Hernia in Infancy and Childhood
1005
and therefore more desirable than the longer-acting curare, which was occasionally used in the past. If the lung cannot be expanded and remains a solid liver-like mass, the prognosis is grave. Furthermore, if the closure of the abdomen requires a struggle with intestines then one may expect a serious outcome. Immediate postoperative positive pressure pneumothorax must be avoided. Careful closure over an expanded lung and an early postoperative x-ray will prevent this complication. Harrington insists on an x-ray before the patient leaves the operating room. CONCLUSIONS
1. Diaphragmatic hernia is "the masquerader of the upper abdomen" (Harrington). The symptoms may resemble malfunction of the heart, lungs or gastrointestinal system. 2. Physical signs in the chest are often so confusing that the diagnosis may be missed if an x-ray is not taken. 3. About 74 per cent of untreated patients die in the first few weeks of life. 4. Diaphragmatic hernia should be suspected in a newborn infant with respiratory or cardiac decompensation. 5. A trained surgical and anaesthetic team should deal with this condition. Acknowledgment The author wishes to thank the University of Toronto Press for their kind permission to reproduce many of the illustrations. REFERENCES Dunhill, T.: Brit. J. Surg. 22: 475,1935. Harrington, S.: Ann. Surg. 115: 705, 1942. Keith, A.: Human Embryology and Morphology. 5th Ed. London, Arnold, 1933. Ladd, W. E. and Gross, R. E.: New England J. Med. 223: 917, 1940. Orr, T. G. and Neff, F. C. J.: Thoracic Surg. 5: 434,1936. Thomson, S. A.: Essays in Surgery. University of Toronto Press, 1950, pp. 240257. 330 Medical Arts Building 170 St. George Street Toronto 5, Ontario, Canada
THE outward obscurity of the diaphragm contributes to the delay and difficulty in diagnosing congenital and traumatic herniae. Congenital diaphragmatic hernia is an uncommon condition which has been emphasized repeatedly in the literature. Until about fifteen years ago the operative mortality in the first year of life was close to 50 per cent. In 1942 Stuart Harrington reported a series of 304 cases of diaphragmatic hernia of which 21 were in children 12 years of age or less. There were 4 deaths in the 21 children operated upon. According to Harrington, the various types of diaphragmatic hernia have the following order of incidence: ADULTS
1. 2. 3. 4.
Oesophageal hiatus Traumatic Subcostosternal Pleuroperitoneal
CHILDREN
1. Pleuroperitoneal 2. Congenital absence of posterior third 3. Oesophageal hiatus 4. Traumatic
The commonest childhood hernia of the diaphragm, the pleuroperitoneal, is an infrequent finding in adults because over 75 per cent of the children suffering from it die if not operated upon before they are a year old. This high mortality in the unoperated cases is due to the fact that the newborn child has not developed a sufficient degree of compensatory cardiac or respiratory reserve to maintain function. Therefore, in an infant with cardiac or respiratory difficulty, the thorax should be examined and x-rayed immediately. Since this type of congenital hernia is recognizable at birth and is a threatening menace to life, immediate operative repair should be carried out. EMBRYOLOGY OF THE DIAPHRAGM
The diaphragm is one of the most complex structures of the body from the standpoint of development. It first appears in the cervical region as * Attending Surgeon, Hospital for Sick Children; Associate in Surgery, University of Toronto, Toronto, Ontario, Canada. 997
998
Stuart A. Thomson
the septum transversum in the first month of fetal life. It immediately begins a rapid descent and is followed by the stomach and elongating oesophagus. During this phase there is a continuous canal behind the septum transversum which connects the pleural and peritoneal coeloms. This dorsal canal is divided in two by the developing dorsal mesentery which includes the oesophagus and stomach. The two canals are then called the pleuroperitoneal canals. During the second intrauterine month the pleuroperitoneal canals are closed by proliferation of the dorsal mesentery and the Wolffian ridge. This is what Dunhill speaks of as the "membranous stage" because the diaphragm is now a complete membrane and a hernia developing at this stage will be a true one with a sac. During the third fetal month a muscle mass followed by the phrenic nerve invades the membranous diaphragm. The posterior part and finally the crus are the last to be transformed into muscle and hence most of the congenital defects occur in these areas. Although the embryology of the diaphragm is very complex, a little knowledge of it helps to explain why some herniae have no sac and others do and again why a large portion of the diaphragm may be absent. The fact that the phrenic nerve is the sole motor supply of the diaphragm seems to make its complex origin doubtful, but this is counteracted by the fact that the muscle mass with its nerve appears after the membranous diaphragm is formed. It would be strange if a structure as complicated in its origin as the diaphragm did not sometimes fail to develop perfectly. It is not surprising that fusion occasionally is less than perfect. The strains to which the diaphragm is subjected in early life are likely to manifest any weakness. ANATOMY
The normally developed diaphragm is a musculo-aponeurotic partition between the thorax and abdomen. It is attached on each side by fleshy digitations to the back of the xiphoid process and the inner surfaces of the lower six costal cartilages and posteriorly from the vertebral column and lumbocostal arches. The vertebral attachments constitute the crura which unite in the midline in front of the aorta. Muscular deficiencies on each side of the xiphoid attachment are filled with areolar tissue and covered ",ith pleura and peritoneum. The superior deep epigastric vessels pass through this space. They are known as the foramina of Morgagni. The aorta passes behind rather than through the diaphragm. The oesophagus passes through an arbour of decussating muscle fibres whereas the caval opening is in the tendinous portion. PATHOLOGY
From the foregoing brief notes on embryology it becomes evident that a hernia will not have a sac if it develops before the end of the second fetal
Diaphragmatic Hernia in Infancy and Childhood
999
month. If development is normal to the second fetal month, then the membranous diaphragm is complete and a subsequent· hernia will have a sac. Herniation through the left diaphragm is four to six times more frequent than through the right side. Massive protection is given to the right side by the right lobe of the liver. Furthermore, the structures in the left hypochondrium are very mobile and thus afford a ready phalanx for a breach. However, exactly the same defects may be found in the right side as are found in the left diaphragm, though o(course the invading structures will differ.
Fig. 254.
Fig. 255.
Fig. 254. Absent posterior third, right diaphragm and most likely the left third as well. Thick pleural sac filled with mediastinal connective tissue and stomach. Fig. 255. Anteroposterior view showing bilateral subcostosternal defect containing transverse colon.
Some of the congenital herniae behave not unlike the acquired adult hernia of the oesophageal hiatus type, as for example, where there was a failure of development of the crural part of the diaphragm (Fig. 254). Here (as in the hiatus cases) the fundus of the stomach had behaved as a sliding hernia and passed up into the posterior mediastinum and then bulged into the right pleural cavity. In the more advanced stage of this type the stomach drags after it the transverse colon, omentum and occasionally the spleen. In our series, the true or sacculated herniae were limited to the cases of congenital absence of the posterior part. The right-sided herniae usually contain stomach, as noted above, or transverse colon, as in the case of the subcostosternal defects (Fig. 255). However, a typical triangular-shaped defect in the posterior leaf of the.
Stuart A. Thomson
1000
right diaphragm may contain all the ileum, caecum, ascending and part of the transverse colon (Fig. 256). Of interest is the fact that bilateral herniation may occur with a large substernal defect (Fig. 255). Herniae through the left leaf of the diaphragm commonly contain varying amounts of small bowel and occasionally all of it (Fig. 257). Adhesions are not common but may occur between the margins of the hernia and the viscera, and occasionally between bowel and lung. In
Fig. 256. Right-sided pleuroperitoneal defect containing most of the ileum, caecum, ascending and part of the transverse colon.
the presence of one congenital anomaly others are liable to occur, such as failure to complete rotation of large bowel. There may also be malformation of the mesentery of both large and small bowel. Awareness of these various pathological states will help in the choice of the surgical approach for repair. SIGNS AND SYMPTOMS
Diaphragmatic hernia in infancy may be confused with any other condition which produces cyanosis, such as cerebral haemorrhage, congenital heart disease, and tracheo-oesophageal fistula. It is important to have the chest examined and to make a flat x-ray plate, because most
Diaphragmatic Hernia in Infancy and Childhood
1001
children with hernia, without a sac, die in the first few hours of life from cardiorespiratory embarrassment. Later in life the symptoms may become quite complex owing to the changeable contents of the hernia with various body positions, and also owing to the health of those viscera within the hernia. An oesophageal hiatus hernia with only part of the fundus of the stomach involved may give rise to more symptoms than a congenital hernia with the entire
Fig. 257.
Fig. 258.
Fig. 257. Left-sided pleuroperitoneal defect through which had passed all the small bowel, filling the entire pleural cavity. Mediastinum and heart appear to be occupying the right pleural cavity. Fig. 258. Same case two weeks after operation shows expansion of left lung and normal restoration of heart and mediastinum.
pleural cavity full of abdominal viscera. Thus, as Harrington has stated, the condition may be termed "the masquerader of the upper abdomen." On the other hand, the symptoms may be quite latent, as in one case where an accident revealed the presence of a congenital defect in the left diaphragm with a recent additional tear (Fig. 259). Intestinal obstruction may occur due to constriction at the neck of the hernia, and occasionally due to adhesions. DIAGNOSIS
For the infant, struggling for its life, a thin barium meal is unnecessary and probably dangerous. For the older patients with occasional
Stuart A. Thomson
1002
bouts of dyspnoea, cyanosis or vomiting, a barium meal is a helpful adjunct to clinical examination and fiat x-ray of the chest. The type of hernia can usually be diagnosed and often the shadow of a sac is seen (Fig. 254). X-rays taken in both horizontal and upright positions help to tell how mobile the hernial contents may be. Anteroposterior and lateral views readily differentiate the substernal type from the posterior group. Dextrocardia may be considered in the diagnosis (Fig. 257). Mediastinal cyst can be a confusing possibility, unless a barium meal is given.
Fig. 259.
Fig. 260.
Fig. 259. Left-sided pleuroperitoneal defect with added traumatic tear. Fig. 260. Same patient one month after operation.
A careful physical examination will usually lead to the correct diagnosis. The important chest findings are tympany, borborygmi, shift of the mediastinum, and distant breath sounds. In the past thirty-two years 39 cases have been found in the Hospital for Sick Children. The ages of the patients ranged from 3 hours to llYz years. Twenty-seven of these were admitted in the last thirteen years and operated upon. TREATMENT
From a review of Table 1 it is obvious that there is nothing to recommend the nonoperative or even delayed treatment of congenital diaphragmatic hernia. In the nonoperative cases there was a mortality of 66.6 per cent with all but one patient dying before 2 months of age. The cases in Table 1 occurred prior to fifteen years ago. Of the 30 patients operated upon, 10 died. In an earlier report of
1003
Diaphragmatic Hernia in Infancy and Childhood
cases seen prior to the end of 1946, 14 patients had been operated upon with only 2 deaths, a mortality of 14.2 per cent. In the last seven years 16 patients have been operated upon with a mortality of 50 per cent. As far as one can determine this recent increase in mortality rate is due to several factors, as follows: (1) Greater awareness of this anomaly and earlier diagnosis. As a Table 1 NON OPERATIVE CASES (Age 6 days to 1172 years) Site of hernia Pleuroperitoneal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Subcostosternal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Congenital absence of posterior third (left) ................ Oesophageal hiatus (left) ................................ TOTAL .................................................. Result Death before 2 months of age ............................. Death at 8 months of age ......................... ········ Apparently alive but could not be traced ..................
6 1 1 1 9 5 1 3
TOTAL .................................................. 9 Table 2
OPERATIVE CASES (Age 3 hours to 1172 years) SITE OF HERNIA
NO. OF CASES
Pleuroperitoneal (none with sac) ..................... ..
17
Congenital absence of posteterior third (all with sac except 3) ..................
9
Foramen of Morgagni ....... Traumatic .................. Para-oesophageal ............ TOTAL ....................
REMARKS
fl
right-sided
RESULT
6 deaths
(I partially traumatic
f7
left
4 deaths
(I right 1 2
1
Bilateral Left-sided Left-sided
- - - - - ---------,---- -----30
result, in these last 16 cases all but 4 patients were under 10 days of age. In this age group diaphragmatic hernia is often attended with other complications and is the greatest challenge. (2) Congenital atelectasis with inability to expand the lung at operation. (3) A wider surgical interest has been attracted so that in this group a larger number of surgeons performed the operation for the first time. Also a much larger number of anaesthetists participatecl, using more varied anaesthetic agents. .
1004-
Stuart A. Thomson
In the past fifteen years, most of the defects in the diaphragm have been repaired with interrupted heavy silk (00 Deknatal). The edges have been slightly overlapped without scarifying so as to allow a double closure. Phrenic nerve crush has not been found necessary in the past ten years. The abdominal approach is best for all left-sided herniae and probably best for most right-sided ones. When using the abdominal approach a long paramedian rectus muscle-splitting incision is made. A high kidney
rest or bolster under the 12th rib offers an excellent exposure (Fig. 261). After reduction and repair of the hernia, the kidney rest is lowered and the abdomen is repaired. A secure closure is best accomplished with stainless steel figure-of-8 buried sutures. This precludes any risk of eventration, makes the nursing care easier and increases the comfort of the patient. Preoperative and postoperative gastric suction for several days is essential. Intratracheal ether anaesthesia is by far the safest and best agent. This anaesthetic may be carried to an apnoeic stage with controlled respirations if necessary. If this does not produce satisfactory relaxation the addition of succinylcholine yvill help. It is a new shorter-acting drug
Diaphragmatic Hernia in Infancy and Childhood
1005
and therefore more desirable than the longer-acting curare, which was occasionally used in the past. If the lung cannot be expanded and remains a solid liver-like mass, the prognosis is grave. Furthermore, if the closure of the abdomen requires a struggle with intestines then one may expect a serious outcome. Immediate postoperative positive pressure pneumothorax must be avoided. Careful closure over an expanded lung and an early postoperative x-ray will prevent this complication. Harrington insists on an x-ray before the patient leaves the operating room. CONCLUSIONS
1. Diaphragmatic hernia is "the masquerader of the upper abdomen" (Harrington). The symptoms may resemble malfunction of the heart, lungs or gastrointestinal system. 2. Physical signs in the chest are often so confusing that the diagnosis may be missed if an x-ray is not taken. 3. About 74 per cent of untreated patients die in the first few weeks of life. 4. Diaphragmatic hernia should be suspected in a newborn infant with respiratory or cardiac decompensation. 5. A trained surgical and anaesthetic team should deal with this condition. Acknowledgment The author wishes to thank the University of Toronto Press for their kind permission to reproduce many of the illustrations. REFERENCES Dunhill, T.: Brit. J. Surg. 22: 475,1935. Harrington, S.: Ann. Surg. 115: 705, 1942. Keith, A.: Human Embryology and Morphology. 5th Ed. London, Arnold, 1933. Ladd, W. E. and Gross, R. E.: New England J. Med. 223: 917, 1940. Orr, T. G. and Neff, F. C. J.: Thoracic Surg. 5: 434,1936. Thomson, S. A.: Essays in Surgery. University of Toronto Press, 1950, pp. 240257. 330 Medical Arts Building 170 St. George Street Toronto 5, Ontario, Canada