Surgical Management of Abdominal Emergencies

Surgical Management of Abdominal Emergencies

Surgical Management of Abdominal Emergencies William D. DeHoff, D.V.M., M.S.* Richard W. Greene, D.V.M.** Thomas P. Greiner, D.V.M.*** The range of ...

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Surgical Management of Abdominal Emergencies

William D. DeHoff, D.V.M., M.S.* Richard W. Greene, D.V.M.** Thomas P. Greiner, D.V.M.***

The range of abdominal emergencies requiring surgical intervention varies widely according to cause, organ systems involved, clinical judgment, and point in time. Basically, this range includes those nonelective surgical procedures demanded for the preservation of life. This report will include those conditions we consider surgical emergencies and the treatment we currently employ. Because of the dynamics of the body and the effects of interruptions to its equilibrium, the point in time is an important consideration. Such interruptions can develop over a considerable period, as in pyometras, so that emergency surgery is required on presentation. Initially, insult may occur without threatening life; however, the animal's condition may deteriorate very rapidly, necessitating emergency surgery. Another generalized type of emergency condition includes those most often associated with trauma, where the animal is normal one moment and hemorrhaging the next. The other important consideration in emergency care is clinical judgment. The time factor is important here as well-whether there is time to take a good history, do a thorough examination, and undertake extensive diagnostic studies. With reference to the 'abdomen, one must determine whether exploratory laparotomy is required or whether the animal should be stabilized, have further diagnostic tests performed, and then be reevaluated. These questions must be weighed in evaluating the emergency patient until a judgment is made as to whether surgical intervention is indicated. If surgery has been elected, whether the diagnosis is definitive or not, a few general principles and guidelines will benefit the eventual result. The goal of emergency surgery is to gain and then retain control of the animal's vital functions. This requires detailed planning and preparation before the emergency arises. The surgical instrument set should be complete and ready at all times, along with the anesthetic equipment, intravenous catheter, fluids and other ther-

The authors thank Mrs. Mary B. Brown, Miss Deena Wolfson, and Mrs. Nancy Stur~e for their assistance in the preparation of the manuscript. *Head of Surgery, The Animal Medical Center, New York. **Staff Surgeon, Section of General Surgery, The Animal Medical Center, New York. ***Staff Surgeon, Section of General Surgery, The Animal Medical Center, New York.

Veterinary Clinics of North America- Vol. 2, No.2 (May, 1972).

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apeutic agents, and a shock treatment tray. Monitoring equipment for urine production, central venous pressure, temperature, and heart sounds can quickly and easily be made operational. The animal's skin should be widely prepared and draped so that anything necessary beyond what is expected or planned can be carried out aseptically. We include suction and cautery with every surgical set-up because we have found that they add to our preparedness. The value of an exploratory laparotomy must be appreciated. Under emergency conditions, there is no dividing line between diagnostics and therapeutics. If the animal's condition becomes progressively worse, and if there are diagnostic indications for abdominal surgery such as continued abdominal hemorrhage, the time required for further diagnostic tests may severely jeopardize the final outcome, and an exploratory laparotomy is considered diagnostic and, hopefully, therapeutic. We perform all exploratory laparotomies and emergency surgery using a ventral midline incision because of its versatility; exposure is wide, and retraction and manipulation of tissue are facilitated. The abdomen should be explored in a planned, systematic manner, ensuring that all organ systems are thoroughly examined. Findings are occasionally negative, but such findings can be considered a positive step in diagnostic determination. Detailed descriptions of the pathophysiologic changes occurring with each condition requiring emergency abdominal surgery are beyond the scope of this paper. However, an awareness of the necessity for fully understanding the effects of such changes within the entire body and the application of basic surgical principles greatly improve the chance of a successful surgical result. "Chance favors the firepared mind."- Louis Pasteur

DIAPHRAGMATIC HERNIAS Diaphragmatic hernias should be treated as emergencies because of their effect on respiratory function. If they are not causing serious interference with respiration at the time of presentation, the herniated portion may enlarge, and the condition may become life-threatening at any time. Diaphragmatic hernia in the dog is'not usually associated with abdominal pain or with symptoms typical of the acute abdomen syndrome, but it is of concern in emergency surgery of the abdomen because of the content of the herniated organs and because we recommend an abdominal approach for its correction. It is also important to recognize that the condition is present before abdominal surgery is undertaken as the presence of the hernia will disturb respiratory function, and death may result. The most common type of diaphragmatic hernia encountered follows traumatic rupture. The sudden increase in abdominal pressure that may occur with a sharp blow or fall is part of the force that ruptures the diaphragm, but factors such as muscular contraction and fixation contribute as well. The resulting tear may be unilateral or bilateral. It may be straight or L-shaped, and often begins at one of the hiatuses. We often encounter costal tears where the diaphragm is torn on one side or the other, and it may be torn trans-sternally; these particular tears are most easily approached for correction through the abdomen. The contents of the hernia vary with the type and location of the tear; depending on the size of the tear and the position of the animal, the contents may remain lodged in the chest or slide back and forth through the tear. Clinical Signs and Diagnosis Clinically, the outstanding sign of a traumatic diaphragmatic hernia is dyspnea. In the acute situation, traumatic shock may mask the symptoms. If the tear

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is large enough to allow the viscera to move back and forth, then dyspnea may be intermittent. In these patients, elevation of the forequarters will effect relief and may suggest the diagnosis. When the viscera are displaced into the chest, the symptoms vary, depending on the amount of thoracic space lost to lung function, and dyspnea is more evident on stress. On auscultation of the thorax, respiratory sounds are mufHed or absent. Peristaltic sounds may be heard if the intestine has herniated, and the heart may be displaced. Hydrothorax is present with displacement of the liver, the degree depending on the amount of strangulation of the liver. An increased area of resonance is apparent on percussion of the thorax when the bowel becomes distended with gas. The diagnosis of diaphragmatic hernia is based on history, clinical signs, and radiographic findings. A history of trauma, such as an automobile accident or fall, along with the above clinical signs, is suggestive of diaphragmatic hernia, and demonstration of the abdominal viscera in the thoracic cavity is diagnostic. The absence of the stomach and spleen on abdominal radiographs can also be used to confirm the diagnosis. Lobes of the liver, spleen, and loops of gasfilled bowel can easily be demonstrated in the thoracic cavity on lateral radiographs, and craniodorsal displacement of the heart, lungs, and trachea may be seen. In the ventrodorsal projection, a soft tissue mass is seen in the posterior thorax, or the mediastinum is displaced to one side if the hernia is unilateral. The outstanding radiographic feature is alteration of the diaphragmatic line or shadow. Contrast radiographs made after a barium swallow reveal portions of the alimentary tract that may be displaced into the thorax. Pneumothorax, hemothorax, hydrothorax, and chylothorax must be considered in the difi'erential diagnosis. Intrathoracic neoplasms, abscesses, and lung torsion also should be considered. Treatment

Emergency treatment is aimed at controlling shock and stabilizing respiratory function. Measures such as thoracic drainage to relieve pneumothorax, if present, and placing the animal in an oxygen cage with the forequarters elevated often relieve the animal until surgical correction can be performed. We prefer to repair the hernia as soon as the animal is believed able to tolerate anesthesia. We prefer the abdomi.nal approach to correction of diaphragmatic hernia unless it is contraindicated by a specific diagnosis of the location of the rupture or by anticipation of additional abdominal injuries. The advantages of the abdominal approach are as follows: 1. Localization of the herniated side is not essential prior to surgery. 2. Bilateral hernia can be corrected through one incision. 3. The involved abdominal viscera can be replaced more accurately. 4. Secondary problems associated with traumatic rupture ofthe diaphragm often occur in the abdomen and can be dealt with effectively. If necessary, the incision can be extended into the thoracic cavity (this has rarely been necessary to date). In deep-chested animals the abdominal approach is relatively difficult, and if the animal's condition permits, further diagnostic studies to localize the lesion are preferred so that a thoracic approach can be used. Positive pressure ventilation is essential and can be accomplished via a positive pressure respirator or manual inflation of the lungs approximately 10 to 15 times per minute with the use of a rebreathing bag. Regardless of means, positive pressure should commence following induction of anesthesia. Surgical Technique. A ventral midline incision is made extending from the xyphoid cartilage to between the umbilicus and pubis. A self-retaining Balfour abdominal retractor is then placed to afford good exposure of the liver and diaphragm. The abdominal viscera should be examined carefully as injury to these

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organs is often associated with diaphragmatic hernias. The tear in the diaphragm should then be identified and its extent determined. If the hernia contains abdominal viscera, a careful examination must be carried out to determine the extent of damage. Splenectomy may be indicated if the spleen is damaged. Evaluation of herniated liver lobes is more difficult. Torsion and strangulation of the liver are common in ventral and costal diaphragmatic tears. Complete strangulation can cause intrahepatic necrosis, leading to severe postoperative complications if the necrotic lobe is not removed. After the liver is replaced in its normal anatomic position in the abdominal cavity, relatively normal color and consistency should return in a reasonable period of time, or the necrotic portion should be removed. Laparotomy pads moistened with warm saline should be used to pack off the abdominal viscera from the diaphragm. Stay sutures of 00 silk or Allis tissue forceps are then used to grasp the edges of the torn diaphragm and hold them in apposition for suturing. We use nonabsorbable suture material, preferably 0 or 00 silk, depending on the size of the animal; chromic catgut of comparable size may be used. A variety of suture patterns may be used, depending on the individual. For straight or V-shaped tears in the muscular or membranous part of the diaphragm, we prefer a layer of simple interrupted mattress sutures, oversewing the edges with a simple continuous pattern to form a seal. Costal tears are sutured with a double layer, continuous suture pattern following the costal arch. We prefer to circumscribe the rib with the first row of sutures. Just before closure is complete, the lungs should be inflated to their full capacity, tying the last suture at the height of inspiration to remove as much air as possible from the thoracic cavity. This eliminates the necessity of a thoracic drain in most cases. If the diaphragm has been severely traumatized or a portion is missing, making apposition of the edges or closure impossible, then a fascial implant or an implant of a synthetic such as Marlex or Arachne mesh may be used to close the defect. The optimal site for obtaining fascia is the tensor fascia lata; the femur is approached laterally, and the desired piece of fascia is removed. The fascia or synthetic is then conformed to and sutured into the defect, using a simple interrupted suture pattern. After the hernia has been corrected, the abdominal incision is closed in a routine manner. When there has been severe trauma, so that an airtight seal on the diaphragm cannot be guaranteed, or when trauma within the thoracic cavity has been significant, a thoracic drain should be employed until all fluid or air has been removed and the thorax appears clear radiographically.

THE LIVER AND GALLBLADDER Emergency surgery involving the liver includes two broad categories: correction of traumatic rupture of the liver and surgery of the biliary tract.

THE LIVER

Blunt trauma to the abdomen often results in injury to the liver. In many cases, mortality rates can be decreased with rapid diagnosis and correction.

Clinical Signs and Diagnosis Rupture of the liver must be suspected in all cases with a history of trauma and signs of abdominal tenderness, hemorrhage, shock, and coma. Blunt hepatic trauma is usually associated with signs of intra-abdominal hemorrhage, detected

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by signs of hypovolemic shock and the presence of blood in fluid removed by abdominal paracentesis. Abdominal paracentesis should be performed using the four-quadrant technique, but absence of blood does not rule out hepatic rupture. Another useful sign of intra-abdominal hemorrhage is the transient relief of shock and hypotension 15 to 20 minutes following the intravenous administration of a balanced electrolyte solution and high doses of corticosteroids. If intra-abdominal hemorrhage has been.considerable or continuous, hypotension often returns shortly after completion of the infusion. · On radiographs of the abdomen, free fluid is suggested by the presence of a uniform density throughout the abdominal cavity, causing poor visualization of the bowel loops and organs. The diagnosis is confirmed by exploratory laparotomy. Treatment

Treatment of hepatic rupture varies according to the degree of injury. Simple hepatic lacerations or perforations which do not continue to bleed are best treated by drainage alone. Four one-half-inch Penrose drains.are placed in the anterior ventral abdomen. They should be placed qn both sides between the liver and the diaphragm and between the liver and stomach and brought to the outside approximately 1 inch from the midline. As a general rule, they should remain in place until there is only minimal drainage of serous fluid; the time may vary from three to seven days. When hepatic lacerations are large or when hemorrhage continues at the time of laparotomy, suture and drainage should be employed. Before these mattress sutures are placed, an attempt should be made to isolate and ligate the bleeding vessels to prevent intrahepatic hemorrhage. Sutures of 0 or 00 chromic catgut using swaged needles with tapered points are placed in a horizontal mattress pattern 1.5 em. from the wound edge on each side, penetrating deeply into the liver. If the edges of the wound cannot be apposed without undue tension, then large ventral mattress sutures on each side of the wound should suffice. We avoid the use of Surgicel, Gelfoam, and similar material because it may cause necrosis, leading to formation of abscesses and peritonitis. Omental tags may be sutured over the laceration for added strength. After the laceration is closed, abdominal drainage is again employed. The most serious injury is the explosive or bursting type of rupture, requiring excision of the involved portion and sometimes even an entire lobe. Hemorrhage may be controlled temporarily by direct pressure with gauze sponges at the site of hemorrhage or by identifying the epiploic foramen of the greater omentum and occluding the celiac artery and portal vein. After the hemorrhage is controlled, the traumatized tissue is removed by the "finger fracture" technique. The liver tissue is crushed between two fingers (Fig. 1), and ligatures are placed around the vessels as they are encountered before they are cut. The fragmentation should follow a line across the liver lobe. After excision of the fragments, the omentum should be placed over the cut surface, the abdomen thoroughly flushed with saline solution, and good abdominal drainage provided. In all of the injury types described above, some bile will escape into the peritoneal cavity. Bacteria of the coliform and, more frequently, proteus types are often present in bile; therefore, appropriate antibiotics should be administered postoperatively.

THE GALLBLADDER

Emergency surgical procedures involving the gallbladder and bile ducts must be performed occasionally. When traumatic rupture of the gallbladder and

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Figure l. Finger fragmentation of the liver ; the ligatu re is p laced around th e crushed portion.

bile d ucts occurs, it is usually associa ted with other h epatic trau ma . Rupture of the gallbladder may also result from calculi and abscessation as an aftermath of cholecystitis. Acute traumatic rupture of the gallbladder or bile duct is usually an incidental findin g on exploration of the abdome n for intra-abdo minal hemorrhage. Rupture as a result of calculi or abscessation presents a clinical picture of peritonitis, and the prognosis is mo re guarded than for traumatic rupture. Because of the branching of the bile duct system, when one of the d ivisional bile ducts is ruptured it can be ligated , and bile will flow satisfactorily through other ducts in the system. 12 Acute Rupture

When acute rupture of the gallbl:'ldde r as a result o f trauma is diagnosed early, the clinical signs are shock, anterior abdominal pain , and indications of intra-abdominal he morrhage. A greenish dischar ge may be a ppa re nt o n abdominal par acentesis, but it is usually masked b y hemorr hage. The diagnosis is confirmed by exploratory laparotomy. The treatment d epends o n where the rupture is located. If o ne of the divisional ducts is ruptured, and if the tear is small, an attempt should be made to suture the torn edges with 5-0 to 6- 0 chromic catgu t in a simple interrupted pattern. If the rent is not accessible for suturing, the n the duct should be ligated on both sides using 00 silk sutures. Bile from the affected lobe will d rain through the auxiliary duct system to a nother divisional duct. Small tears in the gallbladder can be treated by suturing, but cholecystectomy is required for large r tears. A ventral midline incision extending from the xyphoid cartilage to below the umbilicus usually provides wide e nou gh exposure, but a paracostal incision (an incision paralleling the costal arch) can be used in conjunction with th e midline incisio n to facilitate exposure . Placing a moist laparotomy pad between the liver a nd dia phragm also assists in exposure. T he visceral peritoneum is then incised, and the gallbladder is bluntly dissected away from its fossa . T he dissection should be carried to th e entrance of the cystic duct into the common duct. T he three-forceps technique of ligation sh ould then be employed o n the cystic duct, using ligatu res of 00 or 0 silk. An effort should be made to control h emorrhage from the gallbladder fossa.

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Figure 2. Gall bladder perforated by two la rge calculi.

Rupture Due to Obstruction

In the dog, the gallbladder (Fig. 2) also ruptures following obstruction due to calculi or to abscessation. It has occurred in four cases at our hospital in the past four years. Clinical signs include an elevated body temperature, rapid respir ation, deh ydration, and tucking up the abdomen with tenderness on palpation. These signs resulted from peritonitis. In all cases, a greenish-brown, somewhat viscid exudate was re moved by abdo minal paracentesis. On abdominal radiographs, a uniform d e nsity obscuring detail of other organs and free fluid were seen in all cases, and occasionally there was intestinal ileus. Cholecystectomy is r equired for treatment. After removal of the gallbladder, a No . 4 French catheter is passed into the common duct, and gentle irrigation is employed to dislodge a ny calculi that might be present. The cystic duct should be ligated as d escribed previously. The abdomen is then thoroughly irrigated with warm saline solution, and four Penrose drains are placed in the ventral abdomen . Postoperatively, the a nimal should be treated with the a ppropriate antibiotics for peritonitis.

THE PANCREAS Occasio nally, the pancreas is injured by blunt trau ma or a penetrating wound. The pancreas should be examined in all cases of abdominal trauma where an exploratory la par oto m y is performed. The early clinical signs reflect hemorrhage and shock a nd the later signs peritonitis. T he dangers of a ruptur ed pancreas a re intra-abdo minal he morrhage a nd the escape of digestive enzymes. Fr ee pancreatic e nzymes in the abdominal cavity cau se fat necr osis, producing toxemia. Clinically, th e animal has sign s of peritonitis and toxemia. T he diagnosis is confirmed on exploratory la parotomy. Surgical treatment through a midline abdomin al incision is aimed at controlling capilla r y h emorrhage and leakage of enzymes a nd providing good ventral drainage. Ver y small lacerations may be repaired by suturin g the capsule with silk sutures. Catgut sutures ar e subject to enzym e digestion and should not be u sed.

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Large rents are best treated by excision of the affected portion. Mattress sutures of 00 silk are placed through the pancreas at the interlobular septa and tied. The affected portion is then excised, and an attempt is made to close the capsule over the end with a continuous suture pattern of 0000 silk. Excision in a wedge fashion facilitates closure. Care must be taken to preserve the gastroduodenal artery as it runs along the duodenum, as well as the major ducts draining the pancreas into the duodenum. The omentum should not be placed over the repaired surfaces, as the enzymes will again cause fat necrosis. The area should then be thoroughly irrigated and good ventral drainage provided.

THE STOMACH Several conditions involving the stomach must be treated surgically, or death will follow rapidly. Perforation of the stomach and the gastric torsion-dilatation complex are the two most important emergencies, and for eign bodies sometimes pose a problem. Perforation of the stomach usually is caused by penetrating foreign bodies (Fig. 3), but perforation can also have an external source such as a knife or gunshot wound. On rare occasions, invasion of gastric tumors can lead to perforation. We have rarely seen perforation due to gastric ulcers or following an automobile accident. Gastric foreign bodies rarely lead to acute emergencies or surgical problems unless they cause chronic debilitation or complete pyloric blockage. The gastric torsion-dilatation complex should always be considered an emergency and in many cases surgery should take precedence over extensive diagnostic testing. Prolonged dilatation .Jeads to shock and vascular damage to the stomac h which may be irreversible.

Figure 3.

Perforation of the stomach by a stick that had been ingested.

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Clinical Signs and Diagnosis Signs of gastric foreign bodies vary from mild to acute, depending on the nature of the foreign body, the duration of time it has been present, and whether perforation has occurred. The most consistent clinical findings of gastric perforation are vomiting, abdominal tenseness, pain, and increasing shock. The history is of little value unless the owner saw the animal ingest a foreign body or noticed a significant external wound. Radiographically, if a foreign body has caused perforation, free air is seen and peritonitis is evident, and contrast studies demonstrate free contrast media in the abdomen. Gastric tumors causing emergency problems are rare in the dog unless they have ulcerated or penetrated. Contrast radiographs are necessary to demonstrate neoplasms. The most common emergency of the stomach is the gastric torsion-dilatation complex. The gastric torsion is always associated with and is probably preceded by gastric dilatation, but gastric dilatation may occur as a separate entity; however, the clinical signs are very similar. The problem usually occurs in large, deep-chested dogs. The history usually indicates that the dog consumed a large meal two to six hours before showing acute signs of abdominal distention. The dogs are presented with abdominal distention, dyspnea due to anterior displacement of the stomac h , nonproductive vomiting, and excessive salivation. Depending on the duration of the condition, shock is mild to severe. Radiographs should be made only if they do not stress the dog. Then the stomach is usually found to be enlarged and gas-filled and displaced into the anterior abdomen. If gastric torsion is diagnosed, the owner should be advised of its serious nature and that the prognosis is guarded . Treatment Once surgery has been decided on, the proper preoperative fluid therapy, antibiotics and laboratory workup must be performed to aid in success. Anesthe-

Figure 4. the stomach.

Gastrotomy incision, demonstrating correct placement of stay sutures in

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sia with assisted respiration should be administered and carefully regulated throughout the procedure. Gastric Foreign Body. To remove gastric foreign bodies surgically, a ventral midline abdominal incision extending from the xyphoid cartilage to the umbilicus is adequate. The stomach should be exteriorized and packed off with moist laparotomy pads to prevent contamination of the abdominal cavity. After palpating the foreign body, two stay sutures of 00 chromic catgut are placed in the area of the intended incision midway between the greater and lesser curvatures in the least vascular area, to help stabilize the stomach (Fig. 4). The incision is made between the stay sutures, and the foreign body is removed. Suction should be used to remove the gastric contents and prevent abdominal contamination. Any areas of perforation or necrosis are excised at this time. The stomach is closed with two layers of 000 chromic catgut. The first layer should be a continuous Cushing or Connell pattern, with an overlying continuous Lembert pattern. If perforation has occurred or if the abdominal cavity is contaminated, the abdomen should be flushed several times with saline solutions, and abdominal drains placed l inch lateral to the incision. Monofilament stainless steel wire is preferred for abdominal closure if the cavity has been contaminated. Any external wound should be debrided and treated as a contaminated wound. The Gastric Torsion-Dilatation Complex. When the diagnosis of the gastric torsion-dilatation complex has been established, a definite plan of treatment should be followed. 7 Extensive diagnostic tests are often unnecessary and waste valuable time or stress the animal needlessly. Electrolyte imbalance, respiratory embarrassment, vascular hypotension, and gastric mucosal devitalization due to prolonged dilatation are among the secondary problems associated with gastric torsion-dilatation complex and must be considered in developing the plan of treatment. A large-gauge stomach tube should be passed in an attempt to relieve the gas accumulation. Many animals tolerate this without tranquilization, but some may require anesthesia. If anesthesia is necessary, care should be taken to position the head below the body to prevent inhalation pneumonia. An endotracheal tube also should be used. If the tube passes easily without resistance, the gas will be relieved, and the stomach should be flushed with saline to remove all of the contents to help prevent further gas accumulation. If gastric dilatation recurs, a gastropharyngostomy tube can be used, or an exploratory laparotomy should be performed. If the stomach tube cannot be passed, if dilatation recurs, or if other problems such as a twisted spleen are associated with the disease, we strongly recommend surgical intervention. A more conservative approach is recommended by Funkquist8 but in our hands surgery has given the best results. Before the abdomen is explored, a jugular catheter is inserted to enable fluid administration and monitoring of central venous pressure. The cardiopulmonary system should be monitored, and supportive therapy for shock is essential. After induction of anesthesia, positive pressure ventilation is instituted utilizing a cuffed endotracheal tube. A ventral midline incision is employed, extending from the xyphoid cartilage to midway between the umbilicus and the pubis. On the initial incision, care must be taken not to incise the already dilated stomach. The stomach can usually be repositioned by counterclockwise rotation, since the torsion usually is clockwise for 90° to 360°, with the pylorus ventral to the stomach. Ideally, paracentesis should be avoided, but when necessary a needle connected to a suction device is used to avoid abdominal contamination. Repositioning is easier after the air and stomach contents have been removed. After the stomach and spleen are repositioned, the stomach tube is passed,

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the remainder of the stomach contents are removed, and the stomach is flushed with saline solution. The stomach wall is examined for necrosis, and if the color does not return appropriate portions are resected. Splenectomy is performed if the splenic vessels appear thrombosed or if damage appears irreversible. Gastropexy is recommended by some,4 but we have not found it useful in preventing recurrence of torsion. We recommend a pyloroplasty in all cases, since abnormal pyloric function is believed to be part of the etiology. 7 We recommend the Fredet-Ramstedt or Heineke Mikulicz procedure, both of which can be performed in less than five minutes, thereby stressing the animal as little as necessary. We prefer to do the pyloroplasty at the time of initial surgery, but it also can be performed later as a prophylactic measure on an elective basis, especially when dilatation is chronic. If the abdomen has been contaminated, it is flushed with saline, antibiotics are instilled, and Penrose drains are placed lateral to the incision, which should be closed with monofilament stainless steel wire. Postoperatively, intestinal antibiotics are administered orally for two to three days, especially in animals that had perforations. Fluids and antibiotics should be used for five to seven days, especially where peritonitis is suspected. Oral administration of soft food can begin within 24 hours. The Penrose drains are removed when there is no more abdominal discharge. The owners should be made aware that early treatment is essential and that the gastric torsion-dilatation complex may recur.

THE SPLEEN The most common surgical emergency involving the spleen is splenic rupture, due to either tumor or trauma. The most common tumors causing bleeding are hemangiosarcoma and hemangioma. The trauma may be blunt, as from an automobile accident, or penetrating, as from a knife or gunshot wound. Other conditions that could be considered emergencies usually involve disruption of the blood supply to the spleen by blocking or tearing. During the gastric torsion-dilatation complex, the splenic pedicle may become twisted, with the stomach causing acute venous obstruction and thrombosis and massive splenic infarction. Immediate surgical intervention is essential in order to reverse the condition.

Clinical Signs and Diagnosis A ruptured spleen usually is accompanied by a history of trauma, and the signs vary with the degree of damage to the spleen. A small subcapsular hematoma can form on the surface of the spleen and cause no noticeable signs other than mild discomfort. A completely severed spleen, on the other hand, can cause abdominal hemorrhage and signs of hemorrhagic shock, such as pale mucous membranes, excessive salivation, dyspnea, and increased heart rate. There is usually pain in the anterior abdomen, and palpation often reveals a soft enlargement due to a hematoma or large clot formation. The abdomen is distended, and free fluid can also be felt in the abdomen. Blood is often removed via abdominal paracentesis, but the four abdominal quadrants should be explored before the diagnosis is confirmed. The diagnosis of a ruptured spleen cannot be overlooked if blood is not withdrawn when all the other signs are present. On abdominal radiographs, varying amounts of free fluid and intestinal ileus are seen. Following splenic rupture, a clot develops during the acute phase, only to give rise to another hemorrhagic crisis several days later as the clot contracts.

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A ruptured hemangiosarcoma produces varying amounts of free abdominal blood. In most cases, there is no history of trauma, and the dog usually is over l 0 years old. In most cases there has been a gradual weight loss and a gradual onset of clinical signs. There is often a history of a nemia, dyspnea, weakness of the hindlimbs, and abdominal distention. A large, firm mass can be palpated in the anterior abdomen and can be demonstrated radiographically. Thoracic metastases are often demonstrated radiographicall y; therefore, thoracic radiographs are very important in evaluating the patient. Splenic torsion usually occurs in the deep-chested dog following an attack of gastric dilatation or torsion. There is usually pain in the anterior abdomen, a variable degree of shock, and absence of free blood on abdominal paracentesis. The spleen can be palpated easily. Radiographically, the spleen is very enlarged and the abdominal outline is clear, indicating absence of free blood . Treatment

After the animal has been evaluated medically and stabilized with fluids, blood, and corticosteroids, surgery can be performed with less risk. Anesthetics must be administered carefully, and cardiac monitoring is important. A lar ge midline incision is made from the xyphoid cartilage to below the umbilicus to allow proper exposure and exploration of the abdome n for othe1· evidence of trauma or tumor m etastasis. The spleen is exteriorized and held in place with moist laparotomy pads. The abdomen should be explored for evidence of metastasis if a tumorous spleen is to be removed. At this time , a decision should be made as to whether splenectomy is necessary, or whether more conservative measures can be employed. Since most of these cases are surgical emergencies, speed is very important. If splenectomy is elected, mass double clamping of several small vessels, as close to the body of the spleen as possible, is the quickest way of completing the surgery. When all the vessels have been clamped, they are incised between the hemostats, and the spleen is removed. The vessels on the gastric side (Fig. 5) are

Figure 5.

Hemostat used for mass ligation of the splenic pedicle.

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then ligated with either 000 silk or 000 chromic catgut. Care must be taken to preserve the left gastroepiploic artery and vein, which supply the greater curvature of the stomach. After careful examination of all ligatures for seepage, closure is routine. A technique for partial splenectomy has been reported; 14 it may be indicated in some instances when the hematologic effects of splenectomy are of importance or when the benign lesion or rupture involves only a small part of the spleen. The site of partial splenectomy is chosen and is prepared by squeezing the spleen between the fingers. A Doyen clamp is applied to the site, and the blood vessels to the part being excised are isolated and ligated. Two other Doyen forceps are applied to either side of the original clamp, and the spleen is severed at the distal clamp. The pulp is trimmed away, and the cut surface of the spleen is closed with 000 chromic catgut suture in a continuous pattern. If seepage occurs, slight pressure should be applied until it is controlled. A more conservative method of handling a fragmented spleen is placing Surgicel or Gelfoam over the ruptured area and applying digital pressure until the bleeding subsides. This method should not be used if there is any abdominal contamination, since there is the possibility of abscess formation in the clotted material. Postoperative care is routine for the critically ill patient; antibiotics and fluids are administered, and urine output and central venous pressure are monitored. Hemorrhage is rare, but careful observation must be employed during the early postoperative period. Gastric and pancreatic necrosis, increasedincidence of Haemobartonella canis, and hematologic problems have all been considered as postoperative problems of total splenectomy. 5 • 14 For these reasons, greater emphasis might be placed on partial splenectomy. THE SMALL INTESTINE Emergency surgery of·the small intestine usually is performed on animals in which the electrolyte and metabolic balances have been altered. A number of complications often accompany disease conditions such as intussusception, neoplasia, volvulus, incarceration, obstruction, and rupture; these must be treated along with the primary disease. Damage to the intestinal wall and moderate to severe ileus usually are present. If the damage is so severe that rupture occurs, the resulting peritonitis must be treated. There is often insufficient time before surgery to determine and stabilize such imbalances, and the chance for a successful outcome depends on corrective surgery being performed as soon as possible. In such cases, supportive therapy must be instituted immediately, as it will help arrest the progressive deterioration of the animal's condition. Monitoring of the urine output, central venous pressure, and electrocardiograms will provide an indication to the animal's response. Obstructive Foreign Bodies

Obstructive foreign bodies such as a rubber ball or a corncob usually are found in the lower two-thirds of the jejunum and in the ileum. If a foreign body can pass through the pylorus, it usually passes through the duodenum and the first one-third of the jejunum before the intestinal diameter narrows sufficiently to retard its passage. At this point, not only is the patency of the intestinal lumen obstructed, but local occlusion of the mesenteric blood supply of the intestinal wall also begins. First, the capacity for venous absorption is reduced, causing the

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intestinal wall to become edematous, and eventually the arterial blood supply is disrupted, causing necrosis. The intestine proximal to the obstruction becomes distended with fluid and gas, also compromising tissue viability. As a foreign body passes through the duodenum, bowel sounds are increased. The foreign body moves slowly, but forward and reversed peristalsis are stimulated by stretching of the intestinal lumen, often causing vomiting and diarrhea; however, similar signs are seen with simple enteritis. As the passage of the foreign body slows, the intestinal wall becomes edematous· and the lumen narrowed, restricting the passage of the foreign body. As the changes within the involved intestinal segment continue, peristaltic stimulation is blocked, and peristaltic sounds are absent. If the foreign body enters the colon before this occurs, it is usually able to pass. If it has not, surgical removal is required. As the cycle of pathologic changes within the intestinal tract continues, a surgical emergency anses. Clinical Signs and Diagnosis. The outstanding clinical signs of intestinal obstruction are depression, anorexia, abdominal pain, vomiting, and dehydration. If peritonitis is present, body temperature and white blood count are elevated. Progressive circulatory collapse and shock follow if the disease condition remains untreated. High intestinal obstruction, above the jejunum, causes a more acute syndrome than does a lower obstruction. Palpation of an abdominal mass is suggestive of the diagnosis. Radiographic examination may be necessary to reach a definitive diagnosis. The object is visible on plain radiographs if it is radiopaque. Diagnosis of the presence of radiolucent foreign bodies is more difficult, but recognizable changes are present on abdominal radiographs. On the lateral projection, the small intestine is distended proximal to the obstruction and appears as S-shaped coils. Intraperitoneal fluid may accumulate due to transudation from the intestine, obscuring detail of the other abdominal organs. If plain radiographs fail to suggest a diagnosis, oral contrast material such as barium sulfate should be employed to demonstrate the obstructed area. Treatment. The animal is given the necessary fluid and respiratory support during anesthesia. A ventral midline incision is made and the abdominal cavity explored. As a rule, the entire intestinal tract should be examined if one foreign body is found. The intestine should be handled gently with sponges moistened with warm saline. The mass of intestines should be kept inside the abdomen or wrapped in a towel, keeping it warm and moist, and its blood supply must not be traumatized. It is desirable to exteriorize the intestinal portion involved, gently pack off the area, and restrict the areas proximal and distal to the foreign body, preferably with the aid of an assistant. This maneuver is recommended to prevent the fluids accumulated in this area from grossly contaminating the surgical site. If the intestinal segment in which the foreign body is lodged is necrotic, the area to be resected is isolated, and preparation is made for an intestinal anastomosis. If the viability of this area is in question, and if the foreign body is movable, it should be moved into a longitudinal incision on the antemesenteric border, distal to the site of obstruction, for removal. It is important that the incision be large enough to prevent further damage by tearing the intestinal wall during removal. During removal of the foreign body, the segment should be watched closely to ensure that its blood supply is not compromised by its position outside the abdominal wall. After the foreign body has been removed, the viability of a segment is determined by an intact blood supply, warmth, contraction, and continuously improving color. If the segment is viable, then the enterotomy is closed. If it is not viable, it must be resected and an anastomosis performed.

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Nonobstructive Foreign Bodies

The most common nonobstructive surgical problem of the small intestine is the string foreign body, found most often in the cat. The string commonly catches in the mouth or stomach. In the mouth it gets caught around the tongue or over a tooth, or it is attached to a needle lodged in the oropharyngeal cavity. In the stomach it usually knots and cannot pass through the pylorus. If it passes through the pylorus, string or thread passing through the intestinal tract causes enteritis, but there is no serious surgical problem until the string becomes lodged. If it becomes lodged, it begins to cut through the intestine, and complications ensue rapidly. Clinical Signs and Diagnosis. The clinical signs associated with a partially obstructing foreign body are similar to those mentioned for complete obstruction. Depression, anorexia, dehydration, and vomiting are the usual clinical signs. If the string perforates the small intestine, signs of peritonitis and shock will follow. Abdominal palpation usually reveals a gathering of the small bowel into the mid-to-anterior region of the abdominal cavity. Radiographs may be necessary to confirm the diagnosis. On plain radiographs, isolated gas pockets are seen within the intestinal loops, convolutions in the intestinal tract are accentuated, and the small intestine appears plicated in the mid-anterior abdominal region. The plications are better outlined on contrast radiographs. If peritonitis is present, a hazy density in the abdomen tends to obscure detail of the previously mentioned signs. Treatment. The treatment for string foreign bodies is aimed at removing the string with as few enterotomy incisions as possible, thus reducing trauma to the intestine and further perforation by the string. When the string has lodged, the mesenteric border of the intestine is perforated due to peristalsis. Perforation is often incomplete, but the involved area is devitalized. When perforation has not occurred, the string is removed through enterotomy incisions beginning at the duodenum and proceeding distally; incisions are made on the antemesenteric border wherever the string seems to be lodged. Undue tension must not be placed on the string because of the risk of perforation. The enterotomy incisions are closed with 000 chromic catgut in a simple interrupted pattern. If perforation has occurred, the devitalized area should be debrided minimally and sutured with 000 chromic catgut in a simple interrupted pattern. Care must be taken to avoid excess narrowing of the lumen, as strictures may occur. The omentum may be sutured over the perforated area to help prevent intestinal leakage. Intussusception

Numerous causes are implicated in intussusception. Gastroenteritis alone may be responsible, or it may arise secondary to parasites, distemper, neoplasia, or previous intestinal surgery. Intestinal intussusception is an involution of the proximal protion of the intestine into the area immediately distal. This occurs because the proximal portion is smaller owing to a contraction and is then pushed into a dilated distal area. This situation is also encouraged if an end-to-end anastomosis is performed between segments of unequal diameter. The intussusception enlarges by reverse peristaltic action of the distal intestinal segment over the involuted portion. The degree of enlargement is limited by the length of mesentery available. The mesenteric vessels are constricted initially, causing congestion of the venous return which leads to edema of the involved segment. The involuted portion adheres to the distal enveloping segment. Depending on the severity and duration, occlusion of the arterial blood flow eventually leads to necrosis of the intes-

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tina! wall. The necrotic tissue is often contained within the intussuscepted portion, but leakage into the peritoneal cavity can cause peritonitis. Intussusception occurs most commonly at the ileocolic junction. Single or multiple lesions may be found throughout the ileum and jejunum, and double and triple intussusception may occur at one site. Clinical Signs and Diagnosis

The condition presents a variety of clinical signs. It is usually seen in young animals, and the signs are generally those of gastrointestinal obstruction. A tubular mass is usually palpable in the mid-abdomen or right sublumbar area. The abdomen is often tucked up if peritoneal irritation is present. Radiographs may be necessary to reach a definitive diagnosis. Plain radiographs show a cylindrical soft tissue density. An accumulation of air anterior to the mass is evident in the intestinal lumen. Treatment

As in all gastrointestinal tract surgery, thorough inspection of the entire tract is necessary. When the intussusception has been located, manual reduction is attempted by applying gentle continuous pressure at the distal end of the lesion, pushing the intussusception apart. One hand holds the ensheathing layer (the intussuscepiens) and at the same time gently pushes the intussusception proximally. Pulling on the intussusception may rupture the nonviable portions of the intestine. This will slowly break the adhesions and reduce the telescoped area. It is sometimes beneficial to cut the outer serosal layer, permitting the tissue to expand. Once reduced, the intestine is examined for viability. If the area is not viable, then resection and anastomosis are performed. Volvulus

Volvulus of the intestine is rare but does constitute an emergency abdominal condition requiring surgical intervention. There is no breed, age, or sex predisposition. It must be considered in the differential diagnosis in animals with gastric distention. The usual signs are a slow, progressive abdominal distention of the entire abdomen. The animal becomes progressively weak with rapid breathing and poor capillary refill, the beginning of progressive shock. To differentiate volvulus or twisting of the mesenteric root from gastric distention, abdominal distention is easily relieved after passage of a stomach tube if it is due to gastric dilatation. Radiographically, it is demonstrated by large, gas-distended loops of small bowel filling the entire abdominal cavity. Treatment consists of rotating the intestinal tract back to its normal position and inspecting the involved segment of jejunum and ileum for viability. It is important to give endotoxic shock therapy prior to releasing the twisted vessels to help counteract the massive release of toxins into the vascular system. If the intestine is not viable, then resection and anastomosis are required. The prognosis is always guarded, and if resection is required, it is extremely grave. Often a large portion must be removed, and attempts should be made to salvage the ileocolic valve. Over 50 per cent of the small bowel can be resected if the ileocolic valve remains intact, and function will be within accepted limits of normal. Incarceration of the Intestine

Incarceration of the intestine can occur with any hernia: hernias through the mesentery, longstanding or post-traumatic umbilical or inguinal hernias, thoracic, femoral, ventral, abdominal, or diaphragmatic hernias. The clinical signs are similar to those of any abdominal problem that becomes an emergency if the involved portion is devitalized or ruptured. Although the traumatized tis-

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sues surrounding any hernia should be allowed to stabilize before surgical intervention, an exploratory laparotomy must be performed immediately if an incarcerated intestine is diagnosed. The small segment of intestine involved is usually not viable, and anastomosis must be performed.

TECHNIQUE OF ANASTOMOSIS AND ENTEROTOMY The anastomotic and enterotomy technique we employ is aimed at restoration of bowel function as rapidly as possible. More important than the actual technique i~ the surgeon's awareness of the necessity for gentle, atraumatic handling of the intestines. The intestines must be kept warm and moist, and their blood supply mustremain unrestricte d within the abdominal cavity. The area of the intestinal lumen to be opened is gently packed off to prevent gross contamination of the peritoneal surfaces. If an assistant is available, the preferred technique is to have him hold the intestine with warm, saline-moistened sponges just tight enough to prevent spillage of their contents, but not so tight as to impair circulation to the intestinal wall. Sponging of the intestinal incision should be limited; instead , washing with warm saline solution is preferred. This is all d on e in an effort to decrease postoperative ileus, thereby encouraging a rapid return to normal function. The anastomotic technique includes incising the ends to be anastomosed at a 60° angle from the mesenteric border to ensure a g-ood blood supply to the antemesenteric border. The tissues and vessels bordering the mesentery should not be dissected away from the cut edges. A simple interrupted approximating suture pattern of 4-0 chromic catgut with a swaged cutting needle is used. The first suture is placed at the mesenteric border and tie d . The second suture is placed at the antemesenteric border, which now divides the circumference of the intestine into two equal halves. To complete the anastomosis, the remaining sutures are placed about 4 mm. away from the cut edges and should penetrate all layers. They are tied tightly enough to approximate the tissue but not so tightly as to obstruct the associated blood supply. Eight to 12 interrupted sutures usually are sufficient (Fig. 6). Whether an anastomosis or enterostomy is performed , the area of suturing

figu re 6.

l'lacerncnt of silk sutures in a simple interrupted pattern for anastomosis.

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should not be discolored due to trauma to the incised edges at the completion of the technique. The same suture pattern and technique apply to closure of an enterostomy incision. All incisions for an enterostomy should be made longitudinally and at the antemesenteric border. Postoperatively, oral intestinal antibiotics are administered for three days. Small amounts of food and water are made available immediately on recovery from anesthesia. URINARY TRACT The structures of the urinary tract requiring emergency abdominal surgery include the kidneys, the ureters, the bladder, and the pelvic portion of the urethra.

THE KIDNEY

About 20 per cent of all dogs involved in accidents have some kidney trauma. 15 This can vary from mild contusion to the more severe "shattered" kidney13 (Fig. 7). The capsule and peritoneal covering of the kidney form a tough covering which is not easily ruptured except by either direct trauma or compression against the lumbar vertebrae. Only the most severe traumatic lesions such as "shattered" kidney require surgery. Renal and perirenal abscesses can develop from a traumatic hematoma, or pyelonephritis may occur, but the incidence of these lesions has decreased with the wide use of urinary antibiotics. Clinical Signs and Diagnosis When clinical signs of abdominal bleeding follow trauma, rupture of the spleen, liver, or kidney is often suspected, and radiographs are necessary

Figure 7.

Trauma to the kidney, demonstrating capsular rupture and hemorrhage.

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because the clinical signs are similar in all instances. There is anterior abdominal pain and distention, mild to severe shock, and with kidney rupture, varying degrees of hematuria. Bloody fluid is often withdrawn by abdominal paracentesis, but none may be found if the hemorrhage is retroperitoneal. Radiographically, free blood appears as a uniform density obscuring detail throughout the abdomen. Since the affected kidney may not be well defined, the damage is difficult to estimate without an intravenous pyelogram. In some cases, the organs may be clearly defined, indicating absence of free blood, but a large sublumbar density may indicate retroperitoneal hemorrhage. Surgery of the kidney should never be performed without an intravenous pyelogram to evaluate the lesion and the remaining function of the urinary tract. Renal and perirenal abscesses usually cause pain over the lumbar area, elevated temperature, polyuria, and polydipsia, and blood and urine analyses usually indicate infection. Radiographs must be made to differentiate these abscesses from pyometra, with which they can be confused clinically. A good radiographic evaluation is essential before surgery can be performed with any degree of success. If one kidney is affected, the function of the other kidney should be evaluated. Adequate preoperative laboratory tests such as white blood cell count, determination of creatinine and blood urea nitrogen levels, and urinalysis should be performed. Treatment

Supportive fluid therapy should be administered via a jugular venous catheter before induction of anesthesia. A wide midline incision should be used, rather than the flank incision described by some,! so that the entire abdomen can be evaluated properly. Use of an abdominal retractor greatly aids in exposing the kidney. The left kidney is exposed by using the colon and mesocolon to isolate the abdominal viscera. The right kidney is exposed by using the descending duodenum to isolate the abdominal contents. A moist laparotomy pad can also be used to help expose the kidney. The left kidney is easier to approach because of its posterior position and ease of exposure. If the kidney is severely damaged or abscessed, and if the other kidney is functioning normally, a total nephrectomy is performed. The kidney is isolated laterally (retroperitoneally) by blunt digital dissection carried medially over the peritoneal surface. The peritoneum is easily removed and is freed, along with the associated fat, exposing the hilus of the kidney and the renal pedicle. When the peritoneum has been reflected and the vessels exposed, the kidney is easily mobilized. The renal vessels should be carefully isolated to prevent the ligatures from slipping. Using the three-forceps technique, the artery and then the vein should be ligated, each with a transfixing silk suture. The vessels must be ligated with great care, because the renal artery arises directly from the aorta, and the renal vein enters the vena cava directly, and there is a good possibility of each having branches. After the vessels have been doubly ligated, the ureter is similarly ligated. The kidney is then removed. If the abdomen was contaminated during removal of the kidney, it is flushed with warm saline solution and antibiotics, and Penrose drains are placed lateral to the incision. The ligated kidney pedicle should always be examined for hemorrhage. Closure is then routine. Partial nephrectomy using a guillotine technique has been described by Archibald, et aJ.'l This technique can be employed only when at least 50 per cent of the renal parenchyma is healthy; therefore it is useful only when one pole of the kidney is affected. The major complications of the technique as described were secondary hemorrhage, renal atrophy, and formation of urinary fistulas. In most cases, there is only mild damage to the kidney following trauma, and little surgery is necessary. If there is a small tear in the parenchyma, it can be closed using 3-0 chromic catgut sutures in an interrupted mattress pattern. Gel-

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foam can be used to stop small hemorrhages, but its use is discouraged when the abdomen has been contaminated because of the danger of abscess formation: Subcapsular hematomas are treated by incising the capsule, removing the hematoma, and closing the capsule with 3~0 chromic catgut sutures in an interrupted mattress pattern. If only minor contusions or hematomas are found on laparotomy, surgery on the kidney is not necessary, and high dosages of antibiotics are administered to prevent abscess formation.

THE URETER

There are few indications for emergency surgery of the ureter. The most common is traumatic rupture of the ureter in the area of the kidney or in the pelvis-bladder area. Most ruptures seen in our clinic occur in the area of the bladder in association with a fractured pelvis. Ureteral rupture in the kidney area usually is associated with kidney trauma. Ureteral calculi, passing from the kidney, also indicate emergency surgery in rare instances. Clinical Signs and Diagnosis The clinical signs of ureteral rupture are nearly identical to those of lesions of the kidney. Ureteral calculi can elicit signs similar to those of intervertebral disk lesions; therefore disk disease must be included in the differential diagnosis. Dogs usually do not exhibit the intense pain associated with ureteral calculi in man. The blood urea nitrogen level is usually elevated. Radiographs may show a ureteral calculus, but in most cases an intravenous pyelogram is necessary to identify the lesion and to determine. whether blockage is partial or complete. Surgery should not be undertaken without at least a tentative diagnosis, and kidney function should be evaluated carefully. Treatment The surgical technique employed depends on the animal's condition, the location of the lesion, and the extent of damage. The technique also depends on the function of the kidney on the affected side. If trauma to the ureter is severe or if it is blocked with calculi, causing hydronephrosis, a nephrectomy as previously described is indicated. A nephrectomy can be performed safely if the other kidney has good function. Because of its relative simplicity and lack of postoperative complications, nephrectomy is often preferred to specific surgery on the ureter. Ureteral calculi often pass with medical treatment and are usually associated with calculi of the kidney or bladder. We have been able to flush most calculi into the bladder by passing a No.4 French catheter into the pelvis of the kidney and ureter through a nephrolithotomy incision. When the calculus has passed into the bladder, it can be removed via a cystotomy. If it cannot be removed in this manner, a small longitudinal incision is made in the ureter over the calculus, and it is removed. The incision in the ureter can be handled by either stenting or stenting and suturing. For stenting, a No. 4 French catheter or a small polyethylene tube is passed retrograde from the bladder to the kidney and forward from the bladder out the urethra; it is sutured externally. The ureteral wound can be left open to heal as long as the catheter remains in place and there is adequate abdominal drainage. The ureter can also be sutured with the ureteral catheter in place, using 5-0 chromic catgut in an interrupted pattern. The catheter should be removed in seven to ten days. If there is a complete rupture of the ureter, anastomosis can be performed, but the incidence of stricture is high. To accomplish anastomosis, the ureteral

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ends are trimmed to healthy tissue and spatulated, and a catheter is passed across the site from the bladder to the kidney and out the urethra. The anastomosis is completed using 6-0 chromic catgut sutures in an interrupted pattern around the entire circumference of the ureter. The ends of the ureter should be apposed without tension; this may necessitate mobilizing the kidney and ureter as previously described. The catheter must remain in place for five to ten days before being withdrawn to lessen the chance of stricture. An anastomosis should be used in middle tears of the ureter, but transplantation is the technique of choice when the ureter is torn near the bladder. If the ureter will not reach the bladder, the kidney and ureter are mobilized to gain length of the ureter. The ureter is trimmed to healthy tissue and two 6-0 silk stay sutures are placed in the end. A cystotomy incision is made on the ventral aspect of the bladder, and a subserosa! tunnel is made in the bladder wall, puncturing the mucosa through the bladder lumen. The stay sutures in the ureter are grasped through the tunnel by forceps in the bladder lumen, and the ureter is pulled into the lumen of the bladder. The subserosa! tunnel acts as a valve, preventing reflux of urine from the bladder into the ureter. The distal end of the ureter is spatulated and sutured to the bladder mucosa with 5-0 or 6-0 chromic catgut sutures in an interrupted pattern. The cystotomy and abdominal incision are closed routinely, and abdominal drainage is instituted.

THE BLADDER

Urethral obstruction due to calculi with resulting enlargement of the bladder and traumatic or iatrogenic rupture of the bladder are the most common conditions requiring emergency surgery. Other conditions such as tumors or cystitis can cause acute signs, but emergency surgery rarely is required. Cystic calculi rarely cause an emergency; they can be removed through a cystotomy on an elective basis. Calculi obstructing the urethra require immediate attention but are considered in anot!J.er section of this report. Clinical Signs and Diagnosis Traumatic rupture of the bladder following an automobile accident is often overlooked initially; the animal seems to recover partially before deteriorating on the second or third day. The outstanding clinical signs are abdominal tenderness, depression, elevated temperature, and vomiting due to increasing uremia. Bladder rupture is often associated with pelvic rupture. Acidosis may cause panting and dryness of the mucous membranes. In many cases, bloody urine is passed, so that lack of urination cannot be considered the cardinal sign of a ruptured bladder. Radiographically, there is loss of detail of the bladder, peritonitis, and intestinal ileus. On retrograde urography, contrast material is seen throughout the abdomen. An intravenous pyelogram should always be performed when traumatic bladder rupture is diagnosed to determine the status of the rest of the urinary tract. The most common lesion of the bladder following trauma is a simple contusion; the resulting hematuria responds rapidly to conservative medical treatment. Treatment A midline incision should be made from the umbilicus posteriorly to the brim of the pelvis. Suction is necessary to remove the urine from the abdomen. The bladder is exteriorized and packed off with moist laparotomy pads. After the rupture is located, the ureters and the blood supply to the bladder are examined to ensure that they are intact. In many cases, resection of a large portion of the bladder may be required. The edges of the bladder wall are debrided to

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areas of healthy tissue, and the tear is closed in a double layer of 000 chromic catgut sutures in a continuous inverting pattern. Care should be taken not to place any sutures through into the lumen, as they may act as nidi for formation of calculi. In closing the tear, the ureters must not be occluded. The abdomen is then flushed with warm saline solution, and Penrose drains are placed lateral to the incision. An orthopedic procedure may also be required to repair a fractured pelvis. It should be pointed out that a dog can live for several days with urine in its abdominal cavity, but the cat must be operated on immediately if the bladder is ruptured.

THE URETHRA

Urethral rupture can follow trauma, obstruction by calculi, or improper catheterization. The location of the rupture determines the need for emergency surgery. Clinical Signs and Diagnosis Obstruction by urethral calculi, the most common emergency involving the urinary tract in both the dog and the cat, is more common in the male of both species. Signs vary from stranguria to anuria, depending on the degree of blockage and its duration. Age is not a diagnostic clue, as we have seen the condition in several young puppies. If a urethral catheter is passed, resistance usually is met just posterior to the os penis in the dog. The signs of urethral rupture are identical to those described for rupture of the bladder if the rupture is in the pelvic urethra. Other ruptures are usually manifested by swelling, pain, and tenderness due to extravasation of urine into the surrounding tissue. Treatment Since most calculi obstruct the urethra rather than the bladder, cystotomy is rarely necessary to relieve the abstruction. In most instances, the urethral blockage can be removed by retrograde flushing from the urethra, forcing the calculus into the bladder, and relieving the emergency. This procedure should be performed under tranquilization, or in some cases, anesthesia. An indwelling catheter can be left in place, and cystotomy can be performed on an elective basis. If flushing does not relieve the obstruction, and if obstruction or rupture is in the external urethra, a cystotomy in the female or a urethrostomy in the male should be performed. One of three types of urethrostomy can be performed in the male-prepubic, scrotal, or perineal. The prepubic urethrostomy, performed midway between the end of the os penis and scrotum, and the perineal urethrostomy may be either temporary or permanent, whereas the scrotal technique is permanent. A description of these techniques is not within the scope of this report. The urolithiasis syndrome in cats becomes a surgical emergency when the obstruction cannot be relieved or when the urethra is ruptured during attempts to relieve the obstruction. Urethrostomy should be performed immediately. If the laceration is in the pelvic urethra, a laparotomy and symphysiotomy may be necessary to expose the urethra. If a small laceration is present, it can be sutured with 000 chromic catgut in an interrupted pattern. If a complete rupture is present, an anastomosis can be performed with an indwelling catheter in place, using a similar technique as for anastomosis of the ureter.

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AFTERCARE FOR ALL URINARY SURGERY

Following surgery of the urinary tract, the administration of appropriate fluid and antibiotic therapy is extremely important. Abdominal drains should be removed when drainage ceases, usually within two or three days. Indwelling ureteral catheters should be removed in five to seven days. Careful observation for hematuria is essential for the first few postoperative days. Analysis of the calculi removed is important so that specific prophylactic treatment can be initiated to prevent recurrence.

THE MALE REPRODUCTIVE TRACT Conditions of the male genital system that produce acute abdominal signs and require immediate surgical intervention are limited to testicular torsion and abscess of the prostate gland.

THE TESTES

When testicular torsion occurs in the dog, the testis is usually retained in the abdomen. The clinical signs associated with the condition are similar to those of conditions causing the acute abdomen syndrome. The animal stands with an arched back and cries out in pain intermittently. There is marked tenderness in the posterior abdomen, and the animal is reluctant to allow palpation. A mass may be palpable in the posterior abdomen. Absence of one or both testes from the scrotum should be noted. The diagnosis is confirmed on exploratory laparotomy. The torsion may occur in conjunction with a tumor of the testis, which could predispose to torsion. Grossly, the testis appears as a mass engorged with blood, but on exploration the structures can be isolated and identified. The goal of surgical treatment is removal of the testis. The vas deferens and spermatic vessels should be isolated and ligated. If the opposite testis is retained, it should be removed at th.is time.

THE PROSTATE

Most disease conditions of the prostate do not require emergency surgery or cause signs referable to an acute abdominal problem. The exceptions to this are prostatic abscesses, obstructing neoplasms, and trauma to the prostate gland. Prostatic Trauma

Trauma to the prostate gland occurs infrequently and usually is associated with a fractured pelvis. Rupture of the prostatic urethra and trauma to the bladder usually occur with prostatic trauma. Prostatic trauma is confirmed only on exploratory laparotomy because the signs exhibited clinically are referable to a ruptured bladder or urethra. When the condition is diagnosed, treatment is aimed at restoration of the urinary tract. It is not essential to remove the gland or suture the capsule. Hemorrhage should be controlled by ligation, and good ventral abdominal drainage should be provided. Neoplasms

Neoplasms of the prostate gland occasionally present signs referable to an acute abdominal condition. The clinical signs arise because the neoplasm ob-

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structs the ureters, with resultant hydronephrosis and uremia. Before this occurs, signs of debilitation and tenesmus should be apparent, as obstruction of the ureter usually occurs in the terminal stages. The diagnosis can be made by palpation of the obstructing mass in the pelvic canal, along with cystourethrography and an intravenous pyelogram. Surgical treatment of neoplasms of the prostate is unrewarding unless they are diagnosed at a very early stage. Prostatic and Paraprostatic Abscesses

Prostatic abscesses are usually associated with an acute inflammatory reaction and present signs of pain referable to the posterior abdomen. We prefer to divide prostatic abscesses into two groups: those actually involving the gland and those situated around the gland. In the first group, the abscess foci may be disseminated throughout the gland, or there may be one large cavity. The abscess cavity frequently connects with the urethra. In the latter group, the abscess lies on the anterior pole of the prostate gland and may have extensions posteriorly along the rectum. Clinically the signs are similar in both types of abscesses and include an acute inflammatory reaction (high fever, lethargy, and anorexia), as well as posterior abdominal pain and tenesmus. In abscesses involving the parenchyma, hematuria and pyuria may be present, with the blood and pus being excreted at the end of urination. Palpation of the gland per rectum causes pain, and the gland usually is soft, fluctuating, and warm to the touch. In paraprostatic abscesses, a large mass is usually palpable in the abdomen, and an extension along the rectum frequently can be palpated. The diagnosis of prostatic abscess is based on radiographic and clinicopathologic findings. Leukocytosis usually is present, and the blood urea nitrogen level is elevated. Numerous white and red blood cells are found in the urine; this sign usually is not present in the paraprostatic type. Both plain and contrast radiographic studies of the urethra and bladder should be performed. A para prostatic abscess appears as a large circular density impinging on the bladder and extending into the pelvic canal. Contrast material in the bladder will outline its extent. Radiographic diagnosis of an abscess involving the gland itself is more difficult; the condition can easily be confused with benign prostatic hypertrophy. However, with abscess the urethra is frequently dilated at the opening from the prostate gland, and contrast material can be seen diffusing into the gland. The two conditions can be differentiated with the history, clinical signs, and laboratory examinations, since benign prostatic hypertrophy does not present an acute inflammatory reaction. Occasionally the abscess will rupture and the signs are then those of an acute peritonitis. The prognosis in such cases depends on the speed with which treatment is instituted. Surgical treatment of these abscesses varies according to the type of abscess and the animal's condition. We prefer to treat abscesses involving the prostate by total prostatectomy, utilizing the technique described previously. 2 We do not aspirate the abscess because of the high incidence of recurrence and the danger of contamination of the abdominal and pelvic cavities. In those animals that are extremely debilitated or toxic, we recommend fluid therapy to correct dehydration or nutritional deficiency, and high levels of antibiotics to combat the infectious process. The extensive surgical procedure can then be tolerated within approximately 48 hours. Periprostatic abscesses are treated by marsupialization. A ventral midline prepubic incision is made, and the abscess is isolated and packed off with laparotomy pads. A purse-string suture is then placed in the capsule of the prostatic

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abscess surrounding the abscess at a point where it can be placed against the ventral abdominal wall lateral to the midline incision. A small incision is then made in the abscess, and a suction tip is inserted into the abscess while the purse-string suture is tied. After aspiration of the abscess, it is thoroughly irrigated with an antiseptic solution. A 2- to 3-cm. incision is then made in the abdominal wall lateral to the midline incision, and the incised portion of the capsule of the prostate abscess is brought through the incision. The capsule is then sutured to the abdominal fascia and skin using 0000 stainless steel wire in an interrupted pattern, and a Penrose drain is placed in the lumen of the abscess cavity and sutured in place. The ventral abdominal incision is closed with stainless steel wire after irrigation of the peritoneal cavity with an antiseptic solution. Postoperatively, the abscess cavity should be flushed with an antiseptic solution via the Penrose drain for five to seven days. The drain is removed only when drainage is minimal, eight to ten days after surgery. Fluid therapy and antibiotics should also be administered. Rupture of a prostatic abscess requires emergency surgical intervention. The abdominal cavity is explored, irrigated with an antiseptic solution, and drained. Paraprostatic abscesses can be marsupialized; however, rupture of an abscess within the gland presents a more difficult problem. If it does not communicate with the urethra, excision of the diseased tissue, irrigation with antibiotics, and abdominal drainage will be sufficient. When the abscess communicates with the urethra, a urethral catheter should be placed in the urethra and good ventral abdominal drainage provided until the animal can tolerate a total prostatectomy. In all the procedures described, intensive postoperative treatment must be provided. Acute renal shutdown is a common sequela to prostatic surgery. Continuous fluid therapy and monitoring ofthe central venous pressure are necessities. Intravenous Mannitol at the rate of l ml. per pound body weight usually will stimulate the kidneys to produce urine. High doses of corticosteroids during and after surgery are beneficial in combating surgical shock. High doses of antibiotics are also important.

THE UTERUS Disease conditions of the uterus often require emergency surgery. Traumatic injuries resulting from blunt trauma or penetrating wounds are uncommon but do occur. More common conditions are rupture of a uterine horn containing a fetus and rupture of a pyometra. Torsion of a uterine horn can also occur, and usually is associated with pregnancy or pyometra. Pyometra and dystocia should always be evaluated carefully, because emergency surgery may be required.

Trauma and Rupture Injuries to the uterus resulting from blunt trauma and penetrating wounds present variable signs, depending on the portion injured. The signs of rupture or perforation of a uterine vessel are internal hemorrhage and shock, whereas disruption of the uterine wall with displacement of the contents may produce signs of peritonitis. Rupture of the uterus in the gravid state may cause the fetus to be displaced abdominally, resulting in fatal peritonitis if the condition is not detected. Perforations of the uterus following the use of obstetric equipment are not uncommon, but may not be detected until signs of acute peritonitis develop. The history and clinical signs of such perforation are suggestive of the diagnosis, but an exploratory laparotomy usually is required for a definitive diagnosis. Treatment depends on the cause and type of uterine injury encountered.

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Treatment for shock and hemostasis should be instituted immediately. Small tears or perforations in the uterus can be sutured effectively in the absence of a serious peritonitis. Where a large portion of the uterus has been devitalized, or when peritonitis is severe, we prefer performing an ovariohysterectomy and providing good ventral drainage with Penrose drains after thorough irrigation of the abdominal cavity with an antiseptic solution. The prognosis is good if the condition is detected early. Pyometra

When pyometra is diagnosed, the animal should be carefully evaluated for the need for emergency surgery. The condition often develops so gradually that the early stages pass unnoticed, and the animal is not presented until it is toxemic. The sooner surgery is performed under these circumstances, the lower the mortality rate. It is not within the scope of this report to give a detailed account of the etiologic factors and clinical findings associated with pyometra. The syndrome will be discussed only asit relates to emergency surgical treatment. The outstanding clinical feature of pyometra can be divided into two stages-the early stage and the toxemic stage. It is in the toxemic phase that the condition can become a surgical emergency. The toxemic phase is characterized by anorexia, emesis, excessive thirst, dehydration, and extreme depression. The onset usually is sudden. When the cervix is closed, the toxic signs are more severe, and the animal may have a pear-shaped abdominal enlargement when viewed posteriorly. Clinicopathologic findings include a hemogram with a typically moderate to severe leukocytosis ranging from 25,000 to 100,000 cu.mm., pronounced neutrophilia, and many immature neutrophils. The extremely high neutrophil count usually occurs with the nondischarging pyometras. The blood urea nitrogen level may be markedly elevated in the toxic animal as a result of renal failure. The diagnosis is based on the history and on signs of toxicity, vaginal discharge, and uterine enlargement occurring within a few weeks after estrus. In some cases, a hemogram and radiographic examination may be necessary to reach a definite diagnosis. Treatment

It is in the toxemic stage of pyometra that emergency surgery is necessary. Before surgery is performed, renal function should be evaluated carefully and treatment instituted to correct any malfunction. A routine urinalysis and blood urea nitrogen and serum creatinine levels should be determined prior to beginning treatment and contemplating surgery. A continuous intravenous infusion of saline solution and 5 per cent dextrose should be started prior to and during surgery. Massive doses of corticosteroids administered at the time of surgery are beneficial for shock prevention and therapy. The amount of intravenous fluids to be administered can arbitrarily be 10 to 15 mi. per pound of body weight, but the central venous pressure should be monitored continuously. Fluids should be discontinued if the central venous pressure rises above 12 mm. H 2 0. In the event of anuria or renal shutdown, we prefer intravenous Mannitol at a dosage of 0.5 to l mi. per pound of body weight to restore urine output. Surgical Technique. The choice of anesthetic depends on the degree of toxicity exhibited by the animal. Surgery of the extremely toxic or comatose animal is best performed under local anesthesia, supplemented by nitrous oxide and oxygen administered via mask. Induction of anesthesia with a volatile anesthetic such as halothane or methoxyflurane, in conjunction with nitrous oxide

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and oxygen administered via mask, also can be used. In the less toxic animal, induction with an ultra short-acting barbiturate with maintenance on a volatile anesthetic maybe employed safely. An ovariohysterectomy should be performed for correction of the condition. An account of the surgical technique can be found in most surgical textbooks. We prefer to close the abdominal incision with monofilament stainless steel wire because of the risk of evisceration in the toxic, debilitated animal. Ruptured pyometras occur frequently and always require emergency surgery. The clinical signs are similar to those of toxemia, as well as those of peritonitis and shock. Many animals become comatose shortly after rupture occurs, and the speed with which surgery can be performed will determine the outcome. Abdominal exploration and irrigation along with an ovariohysterectomy should be performed. Good abdominal drainage is very important. Treatment for control and prevention of peritonitis should be given.

CESAREAN SECTION

With the exception of a few planned cesarean sections on animals with known anatomic defects, the delivery of feti by hysterotomy should be considered an emergency, because delay only worsens the already toxic state of the animal; particularly important, delay decreases the chance of delivery of live feti. The primary indications for cesarean section are uterine inertia and obstruction of the birth canal. Less common indications are rupture of the uterus as a result of oxytocics and perforation by obstetric instruments. It is not within the scope of this report to present a detailed account of the diagnosis and treatment for dystocia, so our remarks will be limited to the criteria we use to determine indications and the surgical technique employed. An accurate history should be obtained concerning the breeding date, age, and previous breeding history. It is important to know when the first signs of labor were noticed. When dystocia is diagnosed, we recommend a cesarean section when the bitch is exhibiting strong signs of labor and fails to deliver a fetus in 30 to 35 minutes or when weak and infrequent labor fails to be productive after four or five hours. When a bitch has produced one or more feti and then stops, we use oxytocics. lf there is no response to the oxytocic in 45 minutes, we then remove the feti by cesarean section. Surgical Technique. A number of anesthetic combinations can be used successfully, varying from inhalation to epidural agents. We prefer to induce the animal with nitrous oxide and maintain it on ftuothane after intubation. This is a safe anesthetic for the toxic animal, and it causes very little respiratory embarrassment to the feti. A continuous intravenous infusion of saline solution with 5 per cent dextrose added is beneficial, as are massive doses of corticosteroids to prevent shock during the surgery. A posterior ventral midline incision is made from the umbilicus to the brim of the pelvis. The uterus is then exteriorized and packed off with saline-moistened laparotomy pads. An incision is made on the dorsal surface of each horn, and the feti are removed. The incisions are then closed with a double layer of 00 chromic catgut in a right-angle Cushing pattern. After the feti are removed, the uterus should be evaluated carefully. If it appears necrotic and friable, we recommend ovariohysterectomy at this time. After the uterus is removed, the abdominal cavity is irrigated with an antiseptic solution. We do not advocate the use of abdominal drains following cesarean section because of the mammary development. Monofilament stainless steel wire is recommended for closing the linea alba if the feti are allowed to nurse postoperatively.

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AORTIC EMBOLISM IN THE CAT Aortic embolus in the cat has been the object of many studies in the past which have attempted to determine the actual cause-and-effect mechanisms involved. The treatment has been widely discussed and involves a number of different problems. The final treatment of choice has yet to be determined, and is dependent on a full understanding of the pathophysiology of the disease . process in its entirety. Clinical Signs and Diagnosis The most consistent clinical signs of aortic embolism in the cat are sudden pain, paraplegia, loss of femoral pulse, coldness of the rear extremities, and swelling of the quadriceps and gastrocnemius muscles. These signs occur when an embolus is lodged at the bifurcation of the aorta, disrupting the central blood supply to the hindlimbs. The prognosis is always guarded. Aortograms of cats with saddle emboli show occlusion of vessels to the hindlimbs, including the collateral circulation. An interesting fact is that if the same area is occluded artificially, for example by ligatures, the syndrome does not occur. 9 However, it has been demonstrated experimentally that the hindlimb paralysis, muscle damage, and severe vasoconstriction of the central and collateral circulation associated with aortic emboli can be reproduced by injecting the supernatant of lysed red blood cells between two ligatures so placed as to simulate a clinically occurring saddle embolus. 6 All the information gathered to date helps to confirm the theory that emboli lodging in the saddle area, reducing the actual blood flow to the hindlimbs, and the breakdown products of the emboli, causing further vasoconstriction, constitute the most probable mechanism causing the clinical signs. With these things in mind, it is reasonable to conclude that if the embolus were removed early, the course of the disease could be altered beneficially. Treatment If embolectomy is contemplated, certain considerations must be made. The heart is believed to be the source of obstructing material; this has been confirmed in some cases. 10 Major vessels branching from the aorta also may be involved. Therefore the heart, major vessels, and lungs must be evaluated when determining the feasibility of surgery. The heart should be evaluated by auscultation, electrocardiogram, and radiographs to determine the severity of the heart disease, and supportive therapy should be instituted if indicated. The kidneys and intestine also should be examined. If the kidneys are painful on palpation and enlarged, and if the small bowel shows signs of gaseous distention on radiographs, then emboli must be suspected in arteries supplying these areas, and the prognosis is grave. When an animal is presented within six hours after the bnset of signs of paraplegia associated with saddle embolus and has no palpable femoral pulse, a treatable heart condition, and no signs of emboli in the mesenteric or renal arteries, we recommend immediate embolectomy. For embolectomy, a posterior ventral midline approach is used, extending from just above the umbilicus to the brim of the pelvis. The renal and mesenteric arteries can then be visualized anteriorly, and the iliac arteries can be exposed posteriorly. The bladder and colon should be retracted and packed off. The peritoneum and associated fatty tissues are freed, exposing the ventral surface of the distal aorta. Dissection is then continued posteriorly around the iliac arteries until they

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are fully exposed. By palpating the aorta, the proximal portion of the obstruction can be located according to decreased pulsation and a slight firmness of the aorta. Moistened umbilical tapes are placed under the aorta just anterior to the obstruction and around the aorta at the bifurcation of the external iliac arteries. The anteriorly-positioned tape is held up, constricting the aorta, while a No. ll scalpel blade is used to make a stab incision in the aorta. The area between the tapes on the aorta's ventral surface is then incised. The embolus usually protrudes into the opening and can be freed gently with a tissue forceps or sponge. Suction should be used to remove the blood that flows back into the wound from the arteries branching from the aorta. The iliac arteries should be massaged in a retrograde manner to remove any remaining clot. The posterior tape is then tightened to prevent the backflow of blood. The anterior tape is temporarily released so that any emboli in the anterior aorta can be removed. The renal and mesenteric arteries are then examined; if they are also obstructed they are also manipulated retrograde, pushing the emboli into the aorta so that they can be removed through the aortic incision. To close the small incision, which is usually about J em. long, 5-0 or 6-0 silk sutures lubricated with a sterile lubricant such as Vaseline should be used to prevent sawing of tissue. A simple continuous suture pattern placed close to the wound edges is adequate. It is important to take only small bites of tissue to prevent stricture. The aorta must be handled very gently to prevent vasospasm. After the aortic incision is closed, the posterior tape is released, allowing blood to fill the incised segment. The tapes can be removed if there is no leakage of blood. If leakage occurs, a moistened sponge is placed over the suture line, and gentle digital compression is applied while the anterior tape is released. After five minutes of compression, the sponge is removed gently. If leakage continues, compression is applied for an additional five minutes. If there is still leakage along the suture line, a simple interrupted suture should be placed through the area. Postoperative Care The legs become wa'rm, and the femoral pulse returns immediately. Three weeks may be required for full recovery. Supportive therapy should include digitalis glycosides if congestive heart failure is present, steroids for the treatment of shock, vasodilators to prevent vascular spasm, and oxygen to aid respiratory function. 11 The prognosis is guarded to poor, as the condition may recur from days to years after the initial attack. CONCLUSION Emergency surgery of the abdomen, as has been shown, encompasses a variety of clinical problems, many of which have not been considered in this report. Over the past several years, the mortality rate for emergency abdominal surgery has decreased significantly in our clinic. This suggests that therapy has improved, perhaps due in part to the understanding and correct use of fluid and electrolyte therapy and to improved diagnostic procedures. In general, immediate surgery is mandatory when there is evidence of rapid and continued blood loss, when the patient's condition deteriorates rapidly during supportive medical therapy, and when gastrointestinal contents, bile, urine, or pus is removed by abdominal paracentesis. For emergency surgery to be successful, it is necessary to have a plan, make a decision, and act.

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REFERENCES

J. and Allen, A.: An Atlas of Canine Surgery. Philadelphia, Lea and Febiger, 1967. Archibald, J.: Canine Surgery, I st Archibald ed. Santa Barbara, American Veterinary Publications, Inc., 1965. Archibald, .J., Pulman, R. W., and Sumner-Smith, G.: Part.ial nephrectomy-a technique . .J. Sm. Animal Pract., 10:415-417, 1969. Berg, P.: Gastric torsion. In: Kirk, R. W., ed.: Current Veterinary Therapy IV. Philadelphia, W. B. Saunders Company, 1971. Brodie, R. S.: Spleen. In Canine Surgery, 1st Archibald ed., Santa Barbara, American Veterinary Publications, Inc., 1965, 697-713. Butler, H. C.: An investigation into the relationship of an aortic embolus to posterior paralysis in the cat. J. Sm. Animal Pract., 12: 141-158, 1971. DeHoff, W., and Greene, R. W.: Gastric dilatation and the gastric torsion complex. Vet. Clin. North America, Vol. 2, No. I, 1972. Funkquist, B.: Gastric torsion in the dog: non-surgical reposition. J. Sm. Animal Pract., 10:507-511, 1969. Imhoff, R. K.: Nature (London) 192:979, 1961. Imhoff, R. K. and Tashjian, R. ].: Diagnosis of aortic embolism by aortography . .J.A.V.M.A., 139:203-208, 1961. Schwartz, A.: Aortic embolism in the cat. Presented at The Animal Medical Center, New York, 1968. Sleight, D. R., and Thomford, N. R.: Gross anatomy of the blood supply and biliary drainage of the canine liver. Anat. Rec., 166: No.2, 153-160, 1970. Spence, H. M., Baird, S. S., and Ware, E. W.: Management of kidney injuries . .J.A.V.M.A., 154:198-202, 1954. Sumner-Smith, G., and DeBaer, .J.: Partial splenectomy: a technique . .J.A.A.H.A., 7:21-26, 1971. Uberreiter, 0.: Die stumpfen verietzungen der bauchhurle beim hunde. Hanover, M. and H. Schaper, 1930.

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