THE WESTERN Journal of Medice
Refcr to: Levin PM, Shore EH, Treiman RL, et al: Ruptured abdominal aortic aneurysms-Surgic4l treatment. West J Med 123:431-435, Dec 1975
Ruptured Abdominal
Aortic
Aneurysms
Surgical Treatment PHILLIP M. LEVIN, MD; ERNEST H. SHORE, MD; RICHARD L. TREIMAN, MD, and ROBERT F. FORAN, MD, Los Angeles
The records of 62 consecutive patients with ruptured abdominal aortic aneurysms were analyzed to determine what factors contribute to lower mortality. Survival was directly related to the immediate preoperative hemodynamic status of the patients. In 18 cases in which operation was carried out with patients stable, 83 percent of the patients survived. Even if shock was present by the time of operation (37 cases), a 68 percent survival rate was achieved. Cardiac arrest occurred before obtaining aortic control in seven patients and one survived. Survival rates were increased if certain preoperative, operative and postoperative guidelines were followed. Since the combined operative mortality and late graft failure rate in 125 elective aneurysmectomies done during the same decade was under 5 percent, all abdominal aortic aneurysms with few exceptions should be surgically treated before rupture occurs. RUPTURED ABDOMINAL AORTIC ANEURYSMS are associated with high mortality rates. Despite modern surgical techniques, the operative mortality reported for patients undergoing repair of this condition during the last decade has ranged from 40 to 80 percent.1'-13 The experience of DeBakey,14 Mannick15 and more recently Chiariello'6 indicates that a higher rate of survival can be obtained. We have reviewed our experience with ruptured abdominal aortic aneurysms to determine what clinical and technical factors contribute to lower mortality and what areas of management require further improvement. From Cedars-Sinai Medical Center, Los Angeles. Submitted July 14, 1975. Reprint requests to: Phillip M. Levin, MD, Vascular Surgery Associates Medical Group, 435 North Bedford Drive, Beverly Hills, CA 90210.
Clinical Data From October 1964 to October 1974 the authors operated upon 62 patients with ruptured abdominal aortic aneurysms. During the same period 125 elective aneurysmectomies were done. All ruptured aneurysms were infrarenal in location with extravasation of blood into the retroperitoneal tissues or into the free peritoneal cavity. There were no ruptures into either the inferior vena cava or lumen of the bowel. Patients with acutely expanding aneurysms or with dissecting aneurysms involving the abdominal aorta were not included. There was one patient with a false aneurysm of a previously placed aortic homograft. The series included 52 men and 10 women. The average age at time of rupture was 70 years, with THE WESTERN JOURNAL OF MEDICINE
431
RUPTURED ABDOMINAL AORTIC ANEURYSMS
the oldest patient being 85 and the youngest 58. Age distribution by decade is shown in Table 1. Initial symptoms of rupture customarily included sudden severe back pain or abdominal pain, often accompanied by nausea and vomiting. When pain radiated to the flank, groin or scrotum, confusion as to the correct diagnosis frequently resulted. The correct diagnosis was promptly established when a combination of back or abdominal pain (or both), mild or severe shock, and a pulsatile abdominal mass was recognized. The duration of symptoms before admission to hospital is indicated in Table 2. In several cases the diagnosis was obscure because the patients had a history of several days to weeks of back or abdominal pain without evidence of shock or of a pulsatile mass. In many patients the initial period of weakness and shock was followed by a variable period (several hours to several weeks) of recovery of cardiovascular stability before final exsanguinating-type hemorrhage occurred. In others, with massive extravasation of blood, shock was profound from the onset of symptoms and never spontaneously regressed. The sequence of retroperitoneal hemorrhage, tamponade and rebleeding determines the immediate preoperative hemodynamic status of the patients with ruptured abdominal aortic aneurysms (Table 3). Eighteen patients were considered stable at the time of operation, while 37 patients were in shock, and 7 patients sustained a cardiac arrest before obtaining aortic control. Thirteen patients in the series had a known diagnosis of abdominal aortic aneurysm before admission to hospital. The distinct borders that one may palpate in intact aneurysms are often obliterated after rupture. The resulting diffuse and vague outline of the pulsatile mass makes diagnosis more difficult especially in obese patients, where diffuse tenderness may be the principal abdominal finding.
Results The effect of the patient's immediate preoperative hemodynamic status upon survival is shown in Table 3. In 18 cases in which operation was carried out with patients stable, 83 percent of the patients survived. If shock was present by the time of operation (37 cases), a 68 percent survival rate was achieved. Cardiac arrest occurred before obtaining aortic control in seven patients; there was one survivor. During the same decade 432
DECEMBER 1975
* 123 * 6
TABLE 1.-Age Distribution Percent
2 11 6 1
80 and above .......... 7 70-79 ................. 29 60-69 ................. 23 3 50-59 .................
TABLE 2.-Duration
of
Survival 71 62 74 67
Died
Patients
Age
Symptoms
Before
Admission
to Hospital Patients
Time
5 .16 9
Weeks.. 1-6 days . More than 12 hours. Less than 12 hours .17
TABLE 3.-Relationship of Preoperative Hemodynamic Status to Survival Preoperative
Ruptured ........... Cardiac arrest ....... Shock ........... Stable ........... Elective ...........
Percent Survival
Died
Patients
Hemodynamic Status
66
21 6 12 3 5
62 7 37 18 125
14 68 83 96
TABLE 4.-Mode of Management Percent
Survived
Died
Surviv al
Immediate operation . 36 Delay for diagnostic studies or medical
29
7
81
26
14
12
54
Patients
treatment or both
96 percent of 125 patients having elective aneu-
rysmectomies survived. The survival of patients with ruptured abdominal aortic aneurysms as related to their ages at the time of rupture is shown in Table 1. Seventyone percent of the seven patients aged 80 and above survived surgical operation, while 62 percent of those patients in their 70's were able to leave the hospital. Seventy-four percent of patients in their 60's survived, and two of the three patients in their 50's had a successful outcome. The general mode of management in this series of patients is shown in Table 4. When the diagnosis of a ruptured abdominal aortic aneurysm was made without delay, the patient was immediately taken to the operating room. All preoperative preparations were carried out in the operating suite before the induction of anesthesia. Of the 36 patients who received immediate operative treatment 81 percent survived. When diagnosis remained obscure (26 patients), various diagnostic tests or prolonged attempts to improve hemodynamic status were carried out before
RUPTURED ABDOMINAL AORTIC ANEURYSMS
recognition of the ruptured abdominal aortic aneurysm. Under these circumstances, there were 14 survivors (54 percent). The postoperative complications encountered are listed in Table 5. Respiratory insufficiency and renal failure were the most common complications and frequently resulted in postoperative mortality. All patients with renal failure underwent acute hemodialysis and there were 11 tracheotomies done on patients with either pneumonitis or acute respiratory insufficiency. In four patients, jaundice developed in the early postoperative period but this complication never proved fatal. The incidence of myocardial infarction, cerebral-vascular accident and congestive heart failure was quite low. One patient had to be returned to the operating room because of postoperative bleeding. Pancreatic injury, ureteral injury, postoperative small bowel obstruction and perforated duodenal ulcer were infrequent isolated complications encountered in this series.
Discussion The survival rate of 66 percent in a series of 62 patients with ruptured abdominal aortic aneurysms over the past decade is better than that found in many previous reports.'-'3 If those patients are excluded who had sustained a cardiac arrest before aortic control, the survival rate improves to 73 percent. Spontaneous tamponade of retroperitoneal hemorrhage results in a stable preoperative hemodynamic status. Under these circumstances survival (83 percent) approaches that of elective aneurysmectomy. These figures indicate that a more optimistic prognosis is possible for patients with ruptured abdominal aortic aneurysm if certain guidelines of preoperative, operative and postoperative management are followed.
Preoperative This series clearly shows that early diagnosis followed by immediate operation is the essential factor if improved survival rates are to be obtained. This requires a high index of suspicion on the part of internists and general practitioners, as well as surgeons, when an elderly patient presents with a history of acute back or abdominal pain and signs of circulatory instability. Unnecessary and potentially harmful diagnostic studies must be avoided. When immediate operation was un-
TABLE 5.-Complications Associated Type
Number Patients
Pneumonitis respiratory insufficiency 11 Renal failure .......... ......... 7 Jaundice ....................... 4 Myocardial infarction ...... ..... 1 Cerebral-vascular accident ..... ... 2 Congestive heart failure ..... ..... 1 Pancreatic injury ........ ........ 1 Ureteral injury .......... ........ 1 1 Postoperative hemorrhage ........ Small bowel obstruction .....1..... Perforated duodenal ulcer ..... 1...
with Mortality
Postoperativ e
5 4 0 1 1 0 0 0
1 0 0
dertaken in 36 patients, 29 (81 percent) survived. This contrasts with 26 other patients in whom surgical operation was delayed, resulting in a decreased survival rate of only 54 percent. It is noteworthy that 13 patients in this series had a known prior history of an abdominal aortic aneurysm before they presented with rupture. In eight of these patients an early diagnosis was made and operation was undertaken immediatelywith seven survivors. However, among the five other patients the correct diagnosis was not established despite the knowledge of an aneurysm being present. Various diagnostic tests were undertaken before the patient reached the operating room and four of these patients died. As soon as the diagnosis is established the patient should be taken to the operating room and all further preparations made there. Restoration of normovolemia by rapid infusion of blood or colloid frequently results in renewed hemorrhage. Therefore, except for patients in danger of cardiac arrest from exsanguination, massive fluid administration should be withheld until infrarenal aortic control has been obtained. Anesthesia should not be induced until the surgeons are in total readiness, for general anesthesia will frequently deepen shock or precipitate acute collapse in a seemingly compensated patient. The insertion of bladder catheters, central venous pressure monitoring lines and venous cutdowns, and the obtaining of blood for typing and cross-matching must not delay operation but should be carried out concurrently, as rapid control of the aorta followed by restoration of circulatory volume are the immediate requirements for a successful outcome. When an operating room is not immediately available, a circumferential G-suit may temporarily control intraabdominal bleeding.'7 In addiTHE WESTERN JOURNAL OF MEDICINE
433
RUPTURED ABDOMINAL AORTIC ANEURYSMS
tion, the external counterpressure provided by a G-suit may increase arterial pressure from nondiscernible to low-normal levels, allowing more time for preparation of the operating room.
Operative Management The technique of resection of a ruptured abdominal aortic aneurysm has not changed in the past decade. Immediate control of the infrarenal aorta, limited anterior resection of the aneurysm and wrapping the aneurysm wall over the prosthetic graft as a protective cover was practiced in all of these cases. Deliberate left thoracotomy or suprarenal occlusion for aortic control has not been necessary. These methods are frequently ineffective and have been associated with unnecessary complications. Rapid but careful finger dissection in the retroperitoneal hematoma with visual identification of the infrarenal aorta is the best method for obtaining aortic control. Insertion of balloon catheters into the proximal aorta has not been necessary and may cause renal complications by forcing atheromatous material or clot into the renal arteries. Immediately before achieving aortic control the patient is heparinized and blood replacement is started along with the infusion of mannitol. Although controversy still exists regarding the eAlcacy of mannitol in preventing renal shutdown after aortic operation, there is considerable experimental evidence that mannitol does increase renal perfusion during hypotension.'820 If restoration of normovolemia and infusion of mannitol do not achieve diuresis during the operation, furosemide (Lasix®) is also administered. During the operative procedure, several factors tend to produce hypothermia. Profound hypothermia can be avoided by placing a large heating blanket beneath the patient before operation and by running all intravenous fluids through heating units. In addition, heat loss from the peritoneal cavity can be diminished by irrigating the abdomen with warm solutions. Two technical points that deserve emphasis are the secure control of retroperitoneal bleeding and bypass of associated iliac occlusive disease when encountered. Only one patient in this series had to be returned to the operating room for postoperative hemorrhage and this complication was contributory to the patient's death. If massive transfusion has been necessary, the use of protamine sulfate alone may not be sufficient to establish normal coagulation. Fresh whole blood, fresh
434
DECEMBER 1975 * 123 * 6
frozen plasma and platelet packs should be appropriately administered if a coagulopathy has developed. However, careful exploration and the secure control of all bleeding points must be accomplished before continued oozing is attributed to a coagulation defect. Survival is not influenced by the type of prosthetic graft employed. Woven dacron grafts are preferred over knitted dacron because of reduced bleeding through the interstices. There does not appear to be any difference in survival if either a tube or bifurcated graft is used. Of more importance is the decision to bypass significant iliac artery disease if it is present. Aortofemoral bypass should be done whenever necessary rather than attempting anastomosis of a graft limb to an unsuitable iliac artery. The additional operating time required is inconsequential compared to reoperation for an ischemic limb on a critically ill patient. Postoperative Management During the immediate postoperative period continuous assisted ventilation with a volume respirator is almost always necessary and has been extremely helpful in preveniting early postoperative respiratory insufficiency. Assisted ventilation by either oral or nasotracheal tubes should be continued if the patient's arterial blood gas measurements reflect hypoventilation. If respiratory support is still necessary after two or three days, tracheostomy is indicated. Tracheostomy during the early postoperative period may ultimately improve chances of survival because it permits better tracheal toilet and avoidance of the depressive medications which are required to keep the patient on an endotracheal tube. Almost all patients recovering from hypovolemic shock secondary to aneurysmal rupture have at least some mild degree of acute tubular necrosis. If the use of intravenous colloid and furosemide during the early postoperative phase does not result in an appropriate diuresis or if urinary function continues to decline, the patient should receive hemodialysis to avoid the generalized complications of uremia. The anticoagulation required for dialysis does not usually pose a bleeding problem in the patient three to four days following aortic surgery. It is clear on the basis of this experience that early diagnosis and operation are the most important factors in increasing survival following rupture of an abdominal aortic aneurysm. Con-
RUPTURED ABDOMINAL AORTIC ANEURYSMS
trary to some reports, advanced age is not per se a deterrent to achieving survival in this group of patients.2' Certain technical factors contribute to survival as described above. Early use of tracheostomy and hemodialysis can lead to improved survival if postoperative respiratory insufficiency or renal failure has developed. The ratio of ruptured to unruptured abdominal aortic aneurysms is still too high in our experience and reflects a reluctance on the part of some physicians to recommend elective surgical operation for patients with an abdominal aortic aneurysm. Since the combined operative mortality and late graft failure rate with elective aneurysmectomy is under 5 percent, all abdominal aortic aneurysms with few exceptions should be surgically treated before rupture occurs. REFERENCES 1. Hardin ('A: SuLrvival and complications after 121 surgically treated abdominal aneurysms. Surg Gyneco/Obstet 118:541-544, 1964 2. Sanger PW, Robicsek F, Taylor FT, et al: Ruptured aneurysin of the abdominal aorta. North Carolina Med J 25:501-506, 1964 3. Martin P: Ruptured abdominal aortic aneurysm. Proc Royal Coll Surg Eng 867-868, 1965 4. Tracy GD, Reeve TS: Mortality factors in aortic aneurysms. Aust New Zeal J Surg 35:85-93, 1965
5. Lawrence MS, Crosby VG, Ehrenhaft JL: Ruptured abdominal aortic aneurysm. Ann Thorac Surg 2:159-165, 1966 6. Szilagyi DE, Smith RF, DeRusso FJ, et al: Contributions of abdominal aortic aneurysmectomy to prolongation of life-Twelveyear review of 480 cases. Ann Surg 164:678-699, 1966 7. Kouchoukos NT, Levy JF, Butcher HR Jr: Mortality from ruptured abdominal aortic aneurysm. Am J Surg 113:232-235, 1967 8. Graham AL, Najafi H, Dye WS, et al: Ruptured aortic aneurysm. Arch Surg 97:1024-1031, 1968 9. Gwinn CB, Oury JH: A review of abdominal aneurysms at the Naval Hospital, San Diego, California. Am Surg 34:142-144, 1968 10. Berne TV, Wilkinson G: Ruptured abdominal aortic aneurysm. Am Surg 35:36-39, 1969 11. Van Hecckeren DW: Ruptured abdominal aortic aneurysm. Am J Surg 119:402-407, 1970 12. Darling RC: Ruptured arteriosclerotic abdominal aortic aneurysm. Am J Surg 119:397-401, 1970 13. Alpert J, Brief DK, Parsonnet V: Surgery for ruptured abdominal aortic aneurysm. JAMA 212:1355-1359, 1970 14. DeBakey ME, Crawford ES, Cooley DA, et at: Aneurysms of abdominal aorta-Analysis of graft replacement therapy 1-11 years after operation. Ann Surg 160:622-638, 1964 15. Mannick TA, Brooks JW, Bosher LH Jr, et al: Ruptured aneurysm of the abdominal aorta. N Engl J Med 271:915-920, 1964 16. Chiariello L, Reul GJ Jr, Wukasch DC, et al: Ruptured abdominal aortic aneurysm-Treatment and review of 87 patients. Am J Surg 128:735-738, 1974 17. Ludewig RM, Wangensteen SL: Aortic bleeding and the effect of external counterpressure. Surg Gyneco/Obstet 128:252258, 1969 18. Beall AC Jr, Holman MR, Morris GC Jr, et al: Mannitolinduced osmotic diuiresis during vascular surgery-Renal hemodynamic effects. Arch Surg 86:34-42, 1963 19. Peters G, Brunner H: Mannitol diuresis in hemorrhagic hypotension. Am J Physiol 204:553-562, 1963 20. Powers SR Jr, Boba A, Hostnik W, et al: Prevention of postoperative acute renal failure with mannitol in 100 cases. Surgery 55:15-22, 1964 21. Edmunds LH: Resection of abdominal aortic aneurysm in octogenarians. Ann Surg 165:453-456, 1967
Medical Treatment of Duodenal Ulcer By taking antacid one and three hours after a meal (if the patient will take the medicine), gastric acidity is maintained at low level for some three to four hours after a meal. I must emphasize, though, that while this is possible to do in a hospital, it is difficult with patients when they return home. Generally speaking, patients do not take antacids when they are prescribed to them over long periods. Some data: Roth and Burger in 1960 studied patients in hospital who had antacids prescribed for them (generally the amount of antacid ordered was eight ounces per day); when they analyzed how much was taken by the patient, it was only about 31/2 ounces per day, or about 42 percent of that which was prescribed. This was in a hospital and if that happens in a hospital, I am sure it is much worse at home. I want to emphasize, however, that I think with the proper kind of doctor-patient relationship and with proper instruction and emphasis to the patient, we can do much better than that, but this remains to ...
be proved.
-JOHN S. FORDTRAN, MD, Dallas Extracted from Audio-Digest Internal Medicine, Vol. 22, No. 4, in the Audio-Digest Foundation's subscription series of taperecorded programs. For subscription information: 1930 Wilshire Blvd., Suite 700, Los Angeles, CA 90057.
THE WESTERN JOURNAL OF MEDICINE
435
Refcr to: Levin PM, Shore EH, Treiman RL, et al: Ruptured abdominal aortic aneurysms-Surgic4l treatment. West J Med 123:431-435, Dec 1975
Ruptured Abdominal
Aortic
Aneurysms
Surgical Treatment PHILLIP M. LEVIN, MD; ERNEST H. SHORE, MD; RICHARD L. TREIMAN, MD, and ROBERT F. FORAN, MD, Los Angeles
The records of 62 consecutive patients with ruptured abdominal aortic aneurysms were analyzed to determine what factors contribute to lower mortality. Survival was directly related to the immediate preoperative hemodynamic status of the patients. In 18 cases in which operation was carried out with patients stable, 83 percent of the patients survived. Even if shock was present by the time of operation (37 cases), a 68 percent survival rate was achieved. Cardiac arrest occurred before obtaining aortic control in seven patients and one survived. Survival rates were increased if certain preoperative, operative and postoperative guidelines were followed. Since the combined operative mortality and late graft failure rate in 125 elective aneurysmectomies done during the same decade was under 5 percent, all abdominal aortic aneurysms with few exceptions should be surgically treated before rupture occurs. RUPTURED ABDOMINAL AORTIC ANEURYSMS are associated with high mortality rates. Despite modern surgical techniques, the operative mortality reported for patients undergoing repair of this condition during the last decade has ranged from 40 to 80 percent.1'-13 The experience of DeBakey,14 Mannick15 and more recently Chiariello'6 indicates that a higher rate of survival can be obtained. We have reviewed our experience with ruptured abdominal aortic aneurysms to determine what clinical and technical factors contribute to lower mortality and what areas of management require further improvement. From Cedars-Sinai Medical Center, Los Angeles. Submitted July 14, 1975. Reprint requests to: Phillip M. Levin, MD, Vascular Surgery Associates Medical Group, 435 North Bedford Drive, Beverly Hills, CA 90210.
Clinical Data From October 1964 to October 1974 the authors operated upon 62 patients with ruptured abdominal aortic aneurysms. During the same period 125 elective aneurysmectomies were done. All ruptured aneurysms were infrarenal in location with extravasation of blood into the retroperitoneal tissues or into the free peritoneal cavity. There were no ruptures into either the inferior vena cava or lumen of the bowel. Patients with acutely expanding aneurysms or with dissecting aneurysms involving the abdominal aorta were not included. There was one patient with a false aneurysm of a previously placed aortic homograft. The series included 52 men and 10 women. The average age at time of rupture was 70 years, with THE WESTERN JOURNAL OF MEDICINE
431
RUPTURED ABDOMINAL AORTIC ANEURYSMS
the oldest patient being 85 and the youngest 58. Age distribution by decade is shown in Table 1. Initial symptoms of rupture customarily included sudden severe back pain or abdominal pain, often accompanied by nausea and vomiting. When pain radiated to the flank, groin or scrotum, confusion as to the correct diagnosis frequently resulted. The correct diagnosis was promptly established when a combination of back or abdominal pain (or both), mild or severe shock, and a pulsatile abdominal mass was recognized. The duration of symptoms before admission to hospital is indicated in Table 2. In several cases the diagnosis was obscure because the patients had a history of several days to weeks of back or abdominal pain without evidence of shock or of a pulsatile mass. In many patients the initial period of weakness and shock was followed by a variable period (several hours to several weeks) of recovery of cardiovascular stability before final exsanguinating-type hemorrhage occurred. In others, with massive extravasation of blood, shock was profound from the onset of symptoms and never spontaneously regressed. The sequence of retroperitoneal hemorrhage, tamponade and rebleeding determines the immediate preoperative hemodynamic status of the patients with ruptured abdominal aortic aneurysms (Table 3). Eighteen patients were considered stable at the time of operation, while 37 patients were in shock, and 7 patients sustained a cardiac arrest before obtaining aortic control. Thirteen patients in the series had a known diagnosis of abdominal aortic aneurysm before admission to hospital. The distinct borders that one may palpate in intact aneurysms are often obliterated after rupture. The resulting diffuse and vague outline of the pulsatile mass makes diagnosis more difficult especially in obese patients, where diffuse tenderness may be the principal abdominal finding.
Results The effect of the patient's immediate preoperative hemodynamic status upon survival is shown in Table 3. In 18 cases in which operation was carried out with patients stable, 83 percent of the patients survived. If shock was present by the time of operation (37 cases), a 68 percent survival rate was achieved. Cardiac arrest occurred before obtaining aortic control in seven patients; there was one survivor. During the same decade 432
DECEMBER 1975
* 123 * 6
TABLE 1.-Age Distribution Percent
2 11 6 1
80 and above .......... 7 70-79 ................. 29 60-69 ................. 23 3 50-59 .................
TABLE 2.-Duration
of
Survival 71 62 74 67
Died
Patients
Age
Symptoms
Before
Admission
to Hospital Patients
Time
5 .16 9
Weeks.. 1-6 days . More than 12 hours. Less than 12 hours .17
TABLE 3.-Relationship of Preoperative Hemodynamic Status to Survival Preoperative
Ruptured ........... Cardiac arrest ....... Shock ........... Stable ........... Elective ...........
Percent Survival
Died
Patients
Hemodynamic Status
66
21 6 12 3 5
62 7 37 18 125
14 68 83 96
TABLE 4.-Mode of Management Percent
Survived
Died
Surviv al
Immediate operation . 36 Delay for diagnostic studies or medical
29
7
81
26
14
12
54
Patients
treatment or both
96 percent of 125 patients having elective aneu-
rysmectomies survived. The survival of patients with ruptured abdominal aortic aneurysms as related to their ages at the time of rupture is shown in Table 1. Seventyone percent of the seven patients aged 80 and above survived surgical operation, while 62 percent of those patients in their 70's were able to leave the hospital. Seventy-four percent of patients in their 60's survived, and two of the three patients in their 50's had a successful outcome. The general mode of management in this series of patients is shown in Table 4. When the diagnosis of a ruptured abdominal aortic aneurysm was made without delay, the patient was immediately taken to the operating room. All preoperative preparations were carried out in the operating suite before the induction of anesthesia. Of the 36 patients who received immediate operative treatment 81 percent survived. When diagnosis remained obscure (26 patients), various diagnostic tests or prolonged attempts to improve hemodynamic status were carried out before
RUPTURED ABDOMINAL AORTIC ANEURYSMS
recognition of the ruptured abdominal aortic aneurysm. Under these circumstances, there were 14 survivors (54 percent). The postoperative complications encountered are listed in Table 5. Respiratory insufficiency and renal failure were the most common complications and frequently resulted in postoperative mortality. All patients with renal failure underwent acute hemodialysis and there were 11 tracheotomies done on patients with either pneumonitis or acute respiratory insufficiency. In four patients, jaundice developed in the early postoperative period but this complication never proved fatal. The incidence of myocardial infarction, cerebral-vascular accident and congestive heart failure was quite low. One patient had to be returned to the operating room because of postoperative bleeding. Pancreatic injury, ureteral injury, postoperative small bowel obstruction and perforated duodenal ulcer were infrequent isolated complications encountered in this series.
Discussion The survival rate of 66 percent in a series of 62 patients with ruptured abdominal aortic aneurysms over the past decade is better than that found in many previous reports.'-'3 If those patients are excluded who had sustained a cardiac arrest before aortic control, the survival rate improves to 73 percent. Spontaneous tamponade of retroperitoneal hemorrhage results in a stable preoperative hemodynamic status. Under these circumstances survival (83 percent) approaches that of elective aneurysmectomy. These figures indicate that a more optimistic prognosis is possible for patients with ruptured abdominal aortic aneurysm if certain guidelines of preoperative, operative and postoperative management are followed.
Preoperative This series clearly shows that early diagnosis followed by immediate operation is the essential factor if improved survival rates are to be obtained. This requires a high index of suspicion on the part of internists and general practitioners, as well as surgeons, when an elderly patient presents with a history of acute back or abdominal pain and signs of circulatory instability. Unnecessary and potentially harmful diagnostic studies must be avoided. When immediate operation was un-
TABLE 5.-Complications Associated Type
Number Patients
Pneumonitis respiratory insufficiency 11 Renal failure .......... ......... 7 Jaundice ....................... 4 Myocardial infarction ...... ..... 1 Cerebral-vascular accident ..... ... 2 Congestive heart failure ..... ..... 1 Pancreatic injury ........ ........ 1 Ureteral injury .......... ........ 1 1 Postoperative hemorrhage ........ Small bowel obstruction .....1..... Perforated duodenal ulcer ..... 1...
with Mortality
Postoperativ e
5 4 0 1 1 0 0 0
1 0 0
dertaken in 36 patients, 29 (81 percent) survived. This contrasts with 26 other patients in whom surgical operation was delayed, resulting in a decreased survival rate of only 54 percent. It is noteworthy that 13 patients in this series had a known prior history of an abdominal aortic aneurysm before they presented with rupture. In eight of these patients an early diagnosis was made and operation was undertaken immediatelywith seven survivors. However, among the five other patients the correct diagnosis was not established despite the knowledge of an aneurysm being present. Various diagnostic tests were undertaken before the patient reached the operating room and four of these patients died. As soon as the diagnosis is established the patient should be taken to the operating room and all further preparations made there. Restoration of normovolemia by rapid infusion of blood or colloid frequently results in renewed hemorrhage. Therefore, except for patients in danger of cardiac arrest from exsanguination, massive fluid administration should be withheld until infrarenal aortic control has been obtained. Anesthesia should not be induced until the surgeons are in total readiness, for general anesthesia will frequently deepen shock or precipitate acute collapse in a seemingly compensated patient. The insertion of bladder catheters, central venous pressure monitoring lines and venous cutdowns, and the obtaining of blood for typing and cross-matching must not delay operation but should be carried out concurrently, as rapid control of the aorta followed by restoration of circulatory volume are the immediate requirements for a successful outcome. When an operating room is not immediately available, a circumferential G-suit may temporarily control intraabdominal bleeding.'7 In addiTHE WESTERN JOURNAL OF MEDICINE
433
RUPTURED ABDOMINAL AORTIC ANEURYSMS
tion, the external counterpressure provided by a G-suit may increase arterial pressure from nondiscernible to low-normal levels, allowing more time for preparation of the operating room.
Operative Management The technique of resection of a ruptured abdominal aortic aneurysm has not changed in the past decade. Immediate control of the infrarenal aorta, limited anterior resection of the aneurysm and wrapping the aneurysm wall over the prosthetic graft as a protective cover was practiced in all of these cases. Deliberate left thoracotomy or suprarenal occlusion for aortic control has not been necessary. These methods are frequently ineffective and have been associated with unnecessary complications. Rapid but careful finger dissection in the retroperitoneal hematoma with visual identification of the infrarenal aorta is the best method for obtaining aortic control. Insertion of balloon catheters into the proximal aorta has not been necessary and may cause renal complications by forcing atheromatous material or clot into the renal arteries. Immediately before achieving aortic control the patient is heparinized and blood replacement is started along with the infusion of mannitol. Although controversy still exists regarding the eAlcacy of mannitol in preventing renal shutdown after aortic operation, there is considerable experimental evidence that mannitol does increase renal perfusion during hypotension.'820 If restoration of normovolemia and infusion of mannitol do not achieve diuresis during the operation, furosemide (Lasix®) is also administered. During the operative procedure, several factors tend to produce hypothermia. Profound hypothermia can be avoided by placing a large heating blanket beneath the patient before operation and by running all intravenous fluids through heating units. In addition, heat loss from the peritoneal cavity can be diminished by irrigating the abdomen with warm solutions. Two technical points that deserve emphasis are the secure control of retroperitoneal bleeding and bypass of associated iliac occlusive disease when encountered. Only one patient in this series had to be returned to the operating room for postoperative hemorrhage and this complication was contributory to the patient's death. If massive transfusion has been necessary, the use of protamine sulfate alone may not be sufficient to establish normal coagulation. Fresh whole blood, fresh
434
DECEMBER 1975 * 123 * 6
frozen plasma and platelet packs should be appropriately administered if a coagulopathy has developed. However, careful exploration and the secure control of all bleeding points must be accomplished before continued oozing is attributed to a coagulation defect. Survival is not influenced by the type of prosthetic graft employed. Woven dacron grafts are preferred over knitted dacron because of reduced bleeding through the interstices. There does not appear to be any difference in survival if either a tube or bifurcated graft is used. Of more importance is the decision to bypass significant iliac artery disease if it is present. Aortofemoral bypass should be done whenever necessary rather than attempting anastomosis of a graft limb to an unsuitable iliac artery. The additional operating time required is inconsequential compared to reoperation for an ischemic limb on a critically ill patient. Postoperative Management During the immediate postoperative period continuous assisted ventilation with a volume respirator is almost always necessary and has been extremely helpful in preveniting early postoperative respiratory insufficiency. Assisted ventilation by either oral or nasotracheal tubes should be continued if the patient's arterial blood gas measurements reflect hypoventilation. If respiratory support is still necessary after two or three days, tracheostomy is indicated. Tracheostomy during the early postoperative period may ultimately improve chances of survival because it permits better tracheal toilet and avoidance of the depressive medications which are required to keep the patient on an endotracheal tube. Almost all patients recovering from hypovolemic shock secondary to aneurysmal rupture have at least some mild degree of acute tubular necrosis. If the use of intravenous colloid and furosemide during the early postoperative phase does not result in an appropriate diuresis or if urinary function continues to decline, the patient should receive hemodialysis to avoid the generalized complications of uremia. The anticoagulation required for dialysis does not usually pose a bleeding problem in the patient three to four days following aortic surgery. It is clear on the basis of this experience that early diagnosis and operation are the most important factors in increasing survival following rupture of an abdominal aortic aneurysm. Con-
RUPTURED ABDOMINAL AORTIC ANEURYSMS
trary to some reports, advanced age is not per se a deterrent to achieving survival in this group of patients.2' Certain technical factors contribute to survival as described above. Early use of tracheostomy and hemodialysis can lead to improved survival if postoperative respiratory insufficiency or renal failure has developed. The ratio of ruptured to unruptured abdominal aortic aneurysms is still too high in our experience and reflects a reluctance on the part of some physicians to recommend elective surgical operation for patients with an abdominal aortic aneurysm. Since the combined operative mortality and late graft failure rate with elective aneurysmectomy is under 5 percent, all abdominal aortic aneurysms with few exceptions should be surgically treated before rupture occurs. REFERENCES 1. Hardin ('A: SuLrvival and complications after 121 surgically treated abdominal aneurysms. Surg Gyneco/Obstet 118:541-544, 1964 2. Sanger PW, Robicsek F, Taylor FT, et al: Ruptured aneurysin of the abdominal aorta. North Carolina Med J 25:501-506, 1964 3. Martin P: Ruptured abdominal aortic aneurysm. Proc Royal Coll Surg Eng 867-868, 1965 4. Tracy GD, Reeve TS: Mortality factors in aortic aneurysms. Aust New Zeal J Surg 35:85-93, 1965
5. Lawrence MS, Crosby VG, Ehrenhaft JL: Ruptured abdominal aortic aneurysm. Ann Thorac Surg 2:159-165, 1966 6. Szilagyi DE, Smith RF, DeRusso FJ, et al: Contributions of abdominal aortic aneurysmectomy to prolongation of life-Twelveyear review of 480 cases. Ann Surg 164:678-699, 1966 7. Kouchoukos NT, Levy JF, Butcher HR Jr: Mortality from ruptured abdominal aortic aneurysm. Am J Surg 113:232-235, 1967 8. Graham AL, Najafi H, Dye WS, et al: Ruptured aortic aneurysm. Arch Surg 97:1024-1031, 1968 9. Gwinn CB, Oury JH: A review of abdominal aneurysms at the Naval Hospital, San Diego, California. Am Surg 34:142-144, 1968 10. Berne TV, Wilkinson G: Ruptured abdominal aortic aneurysm. Am Surg 35:36-39, 1969 11. Van Hecckeren DW: Ruptured abdominal aortic aneurysm. Am J Surg 119:402-407, 1970 12. Darling RC: Ruptured arteriosclerotic abdominal aortic aneurysm. Am J Surg 119:397-401, 1970 13. Alpert J, Brief DK, Parsonnet V: Surgery for ruptured abdominal aortic aneurysm. JAMA 212:1355-1359, 1970 14. DeBakey ME, Crawford ES, Cooley DA, et at: Aneurysms of abdominal aorta-Analysis of graft replacement therapy 1-11 years after operation. Ann Surg 160:622-638, 1964 15. Mannick TA, Brooks JW, Bosher LH Jr, et al: Ruptured aneurysm of the abdominal aorta. N Engl J Med 271:915-920, 1964 16. Chiariello L, Reul GJ Jr, Wukasch DC, et al: Ruptured abdominal aortic aneurysm-Treatment and review of 87 patients. Am J Surg 128:735-738, 1974 17. Ludewig RM, Wangensteen SL: Aortic bleeding and the effect of external counterpressure. Surg Gyneco/Obstet 128:252258, 1969 18. Beall AC Jr, Holman MR, Morris GC Jr, et al: Mannitolinduced osmotic diuiresis during vascular surgery-Renal hemodynamic effects. Arch Surg 86:34-42, 1963 19. Peters G, Brunner H: Mannitol diuresis in hemorrhagic hypotension. Am J Physiol 204:553-562, 1963 20. Powers SR Jr, Boba A, Hostnik W, et al: Prevention of postoperative acute renal failure with mannitol in 100 cases. Surgery 55:15-22, 1964 21. Edmunds LH: Resection of abdominal aortic aneurysm in octogenarians. Ann Surg 165:453-456, 1967
Medical Treatment of Duodenal Ulcer By taking antacid one and three hours after a meal (if the patient will take the medicine), gastric acidity is maintained at low level for some three to four hours after a meal. I must emphasize, though, that while this is possible to do in a hospital, it is difficult with patients when they return home. Generally speaking, patients do not take antacids when they are prescribed to them over long periods. Some data: Roth and Burger in 1960 studied patients in hospital who had antacids prescribed for them (generally the amount of antacid ordered was eight ounces per day); when they analyzed how much was taken by the patient, it was only about 31/2 ounces per day, or about 42 percent of that which was prescribed. This was in a hospital and if that happens in a hospital, I am sure it is much worse at home. I want to emphasize, however, that I think with the proper kind of doctor-patient relationship and with proper instruction and emphasis to the patient, we can do much better than that, but this remains to ...
be proved.
-JOHN S. FORDTRAN, MD, Dallas Extracted from Audio-Digest Internal Medicine, Vol. 22, No. 4, in the Audio-Digest Foundation's subscription series of taperecorded programs. For subscription information: 1930 Wilshire Blvd., Suite 700, Los Angeles, CA 90057.
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