General surgical complications after cardiac surgery

Abdominal organ injury after cardiac surgery

Gastrointestinal complications occur in about 2.5% of patients undergoing cardiac surgery, are associated with a high mortality (about 33%), and account for nearly 15% (and perhaps increasing) of all postoperative deaths. The various complications and risk factors are reviewed. Splanchnic ischemia prior to, during, and especially postoperatively appears to be an important cause of these complications. In addition, splanchnic ischemia is hypothesized to be one cause of the systemic inflammatory response syndrome and multiorgan failure that may follow cardiac surgery. The physiology of splanchic perfusion and the effects of cardiac surgery, including cardiopulmonary bypass, on it are reviewed. Finally, possible methods to minimize splanchnic ischemia and reduce the incidence of abdominal complications are discussed.

Predictors and outcomes of gastrointestinal complications in patients undergoing coronary artery bypass graft surgery: A prospective, nested case-control study1 1No competing interests declared

BACKGROUND

The aim of this study was to assess risk factors and outcomes of gastrointestinal (GI) complications in patients undergoing coronary artery bypass surgery (CABG).

STUDY DESIGN

We conducted a nested case-control study from a 9-year hospitalization cohort (n = 7,345) in which data were collected prospectively. Patients developed GI complications (n = 66) and controls did not (n = 330). Cases were matched to controls 1:5 on type of surgery. We examined 16 risk factors and 14 outcomes.

RESULTS

Five risk factors proved significant in predicting GI complications. Patients were more likely to be older than age 70, to be on dialysis, to have left ventricular hypertrophy, and to be on anticoagulants; the procedure was also more likely to be urgent. There was no significant difference between the cases and controls for the remaining 11 risk factors. We also computed correlation coefficients among the significant variables; using regression analysis, we found that patients undergoing CABG had a threefold increase in the risk of GI complications if they were older than age 70 (odds ratio [OR] 1.06, 95% CI 1.03 to 0.97), if they were on dialysis (OR 1.87, 95% CI 1.98 to 1.22), and if their procedure was urgent (OR 1.91, 95% CI 1.07 to 3.4). Eleven outcomes proved significant. Patients with GI complications ran a greater risk of mortality; required more additional procedures; suffered arrhythmia that required treatment; and were more likely to have neurologic, pulmonary, renal, and sternal wound complications. They also had greater length of hospitalization, intensive care unit length of hospitalization, ventilator time, and postoperative creatine phosphokinase levels.

CONCLUSIONS

In patients undergoing CABG surgery, urgency of the procedure, age greater than 70 years, and dialysis all significantly increased the risk of a GI complication. Patients with GI complications also experienced more negative outcomes.

Effectiveness of lactulose syrup after cardiac surgery

Dutch cardiac surgery centers lack consistency in management with respect to the prevention of postoperative constipation. Although not based on any evidence, the administration of lactulose syrup is widely used. Because it often causes intestinal discomfort such as abdominal pain, bowel cramps, and feelings of distention, a study was performed in postoperative cardiac surgery patients who were given either standard care (routine administration of lactulose syrup twice daily) or laxative on indication. Postoperative constipation appeared equally frequent in both groups, and patients who received lactulose had more symptoms of intestinal discomfort. Based on these findings, it is safe to abolish the routine management of postoperative laxatives on a cardiac surgery ward.

The acute abdomen in the critically ill patient

The critically ill patient with an acute abdomen represents a great challenge for the surgeon. The physiologic derangement that is associated with the critically ill state both fuels and is fueled by acute abdominal processes. Improvements in critical care and cardiopulmonary bypass technique have allowed for a group of patients to evolve that are susceptible to the complications of prolonged flow states. This article focuses on the abdominal consequences of support of the critically ill patient, as well as, the diagnostic and therapeutic options that are available to treat these patients.

Perforated diverticulitis following extra-abdominal surgery

The peritonitis of perforated diverticular disease is a life-threatening condition. We report three cases where it occurred following unrelated extra-abdominal surgery and where surgical intervention proved to be the correct course of management. All cases were treated with a Hartmann's procedure; this is probably the safest option for purulent peritonitis in patients who are a high operative risk and have recently undergone major surgery.

The incidence of gastrointestinal symptoms in cardiac surgery patients through six weeks after discharge

OBJECTIVE

To determine the incidence and the effect of intraoperative and discharge variables on gastrointestinal (GI) symptoms after cardiac surgery during hospitalization and 2 and 6 weeks after discharge.

DESIGN

Prospective and descriptive.

SETTING

Two university-affiliated medical centers.

PATIENTS

One hundred twenty-two adult patients undergoing cardiac surgery.

OUTCOME MEASURES

Frequency of GI symptoms and level of distress caused by GI symptoms during hospitalization and 2 and 6 weeks after hospital discharge.

INSTRUMENTS

GI symptoms were measured by The Gastrointestinal Symptom Frequency and Symptom Distress Scale. Depression was measured by The Center for Epidemiologic Studies Depression Scale.

INTERVENTION

Demographic and physiologic variables were collected by chart review. Patients completed the Gastrointestinal Symptom Frequency and Symptom Distress Scale and The Center for Epidemiologic Studies Depression Scale in the hospital. Telephone interviews were used to collect 2- and 6-week data.

RESULTS

Fifty-seven percent of patients after surgery reported poor appetite, 37% lack of taste, and 34% nausea during hospitalization. The frequency of all GI symptoms decreased with time; 19% of subjects reported poor appetite, 19% lack of taste, and 10% nausea at 6 weeks after discharge. Although poor appetite occurred with the greatest frequency, patients reported the greatest distress with lack of taste. When analyzed with a logistic regression model, use of antihypertensive agents was associated with lack of taste; use of diuretic and antiarrhythmic agents was associated with nausea; and level of depression was associated with all three GI symptoms. Length of cardiopulmonary bypass time mean arterial blood pressure during surgery, mixed venous oxygen saturation during surgery, and subject age did not significantly affect the frequency of GI symptoms at any data collection point.

CONCLUSIONS

The incidence of GI symptoms after cardiac surgery is significant, but their etiology has yet to be determined.

Colorectal complications following cardiac surgery. Six-year experience

PURPOSE

This study was undertaken to assess colorectal complications following cardiopulmonary bypass surgery.

METHOD

This is a retrospective review of 5,801 patients who underwent 5,801 cardiopulmonary bypass procedures from 1985 to 1991. Patients were evaluated for type of bypass procedure, postoperative colorectal complications, age, sex, bypass time, aortic cross-clamp time, elective vs. emergency cases, uses of intra-aortic balloon pump, perioperative hypotension, and use of vasopressors. Statistical analysis was performed using chi-squared analysis and Student's t-test.

RESULTS

Nineteen of the 5,801 patients developed 19 colorectal complications, a prevalence of 0.3 percent for the initial hospital stay following bypass surgery. Mortality in those with complications was 37 percent (7/19). Of the 19 complications, 9 (47 percent) followed coronary artery bypass grafting, whereas 10 (53 percent) followed valve replacement or combined coronary artery bypass grafting with other cardiac procedures. Five (26 percent) of the complications followed emergency cases, whereas 14 (74 percent) followed elective cases. Average age of those with complications was 69.8 years, compared with 63.2 years for those without complications. Average aortic cross-clamp time for those with complications was 71 +/- 25 minutes; pump time was 106 +/- 34 minutes. That was significantly higher than in those without complications. Nine (47 percent) patients with complications required vasopressors during the perioperative period, whereas eight (42 percent) suffered prolonged hypotension (systolic blood pressure, < 90 mmHg).

CONCLUSIONS

It appears that increased age, valve replacement, or combined cardiac procedures, emergency procedures, and prolonged aortic cross-clamp and bypass pump times are risk factors for development of colorectal complications. Hypoperfusion, as suggested by prolonged pump times, clamp times, and emergency procedures may be a possible cause for development of colorectal complications.

General surgical complications can be predicted after cardiopulmonary bypass

OBJECTIVE

The authors review the general surgical complications of cardiopulmonary bypass, including newer procedures such as heart and lung transplantation, to identify patients at higher risk.

SUMMARY BACKGROUND DATA

Although rare, the general surgical complications of cardiopulmonary bypass are associated with high mortality. The early identification of patients at increased risk for these complications may allow for earlier detection and treatment of these problems to reduce mortality.

METHODS

A retrospective review was performed of 1831 patients undergoing cardiopulmonary bypass from 1991 to 1993. This was done to identify factors that significantly contributed to an increased risk of general surgical complications.

RESULTS

Factors associated with an increased risk of general surgical complications included prolonged cardiopulmonary bypass (p < 0.005) and intensive care unit stay (p < 0.002), occurrence of arrhythmias (p < 0.001), use of inotropic agents (preoperatively or postoperatively p < 0.001), insertion of the intra-aortic balloon pump (preoperatively p < 0.005, postoperatively p < 0.001), use of steroids (p < 0.001), and prolonged ventilator support (p < 0.001). Multivariate analysis identified use of the intra-aortic balloon pump (p < 0.001) as the strongest predictor of the general surgical complications of cardiopulmonary bypass. A variety of factors not contributing significantly to an increased risk also were identified.

CONCLUSIONS

Factors indicative of or contributing to periods of decreased end-organ perfusion appear to be significantly related to general surgical complications after cardiopulmonary bypass.

Imaging of abdominal complications following cardiac surgery

Ten thousand seven hundred fifty-six patients underwent cardiac bypass surgery at the Mater Hospital national cardiac unit between September 1979 and April 1993. Of this group, 49 patients were identified who had developed postoperative gastrointestinal complications leading to 16 deaths. Twenty-five patients developed gastrointestinal hemorrhage, eight patients developed gallbladder disease, five patients developed phlegmonous pancreatitis, eight patients developed bowel perforations, and three patients developed intestinal pseudoobstruction. The particular radiological features that lead to diagnosis in each case are discussed and relevant literature is briefly reviewed.

Abdominal complications following cardiac surgery

Between 1978 and 1991, 116 of 19,246 patients (0.6%) undergoing cardiac surgery developed abdominal complications (renal/hepatic failure excluded) within 30 days of their cardiac operation. Comparison with a randomly selected control group of 217 patients operated upon over the same period of time was also undertaken. Compared to the control group, the study patients were older (mean age, 63.3 +/- 12.5 years vs 57.5 +/- 21.5 years; P = 0.03), more likely to have a history of alcohol abuse (10% vs 4%; P = 0.03), and more likely to have a previous history of gastrointestinal problems (43% vs 17%; P = 0.0001). There was also a trend towards a greater number of patients having valvular surgery, particularly reoperative surgery, in the study group. Postoperatively, patients with marked low cardiac output, requiring the intra-aortic balloon pump, were more likely to develop abdominal complications. These complications included complicated peptic ulcer disease in 54 (47%), intestinal obstruction and/or perforation in 19 (16%), biliary tract disease in 13 (11%), mesenteric ischemia in 13 (11%), acute pancreatitis in 3 (3%), and miscellaneous complications in the remaining 14 (12%). Forty-three patients were treated medically and 73 patients required operative intervention. The surgical procedures performed were truncal vagotomy and drainage (12), oversewing of a perforation or a bleeding vessel (6), gastrectomy (2), intestinal resection (14), laparotomy only (14), cholecystectomy (14), and other (11). Mortality was 26% (30/116) with the mortality for medical and surgical treatment being 16% vs 32%, respectively (P = 0.112). Intestinal ischemia had the highest mortality, with a rate of 85% (11/13). Despite intensive monitoring and care of cardiac surgical patients, abdominal complications do occur, although rarely. Risk factors include older age, a positive history of gastrointestinal disease, reoperative valve surgery, and severe postoperative low cardiac output.

Acute mesenteric ischemia after cardiopulmonary bypass

Three thousand sixty-six patients underwent cardiopulmonary bypass at the Maimonides Medical Center over a 5-year period from January 1, 1987, to January 1, 1992. Of these patients, 1,890 (62%) were less than 70 years of age, 969 (32%) ranged from 70 to 79 years of age, and 207 (7%) were 80 years of age or older. The overall 30-day mortality rate was 8%. Eleven patients developed acute mesenteric ischemia from 24 hours to 12 days postoperatively. At the time of diagnosis, the majority of patients presented with late classical signs and symptoms of acute mesenteric ischemia including abdominal distension, respiratory distress, hypotension, oliguria, and sepsis. All patients underwent immediate laparotomy. Extensive bowel necrosis was found in all, and resection was possible in eight patients. All patients died as a result of this complication. Using the exact trend test, we found a statistically significant increase in the incidence of deaths due to acute mesenteric ischemia after cardiopulmonary bypass in older compared with younger patients. This fatal complication after cardiopulmonary bypass occurs more often than previously believed and is a relatively common cause of death in the elderly.

Intraabdominal complications after cardiopulmonary bypass

Thirty-three intraabdominal complications occurred in 27 patients over a 16-year period in 4,629 patients who underwent cardiopulmonary bypass (0.58% incidence). The mortality was 14.8% for the intraabdominal complication group compared with 3.4% for the control group of patients (p less than 0.01). The most common complication was gastrointestinal hemorrhage (n = 20), of which esophagitis (n = 6) was the most common cause. However, patients with duodenal ulcer (n = 4) had the highest mortality; 2 patients who underwent truncal vagotomy and pyloroplasty subsequently died. Two further patients underwent operation for perforated anterior duodenal ulcers without further morbidity. Cholecystitis developed in 5 patients and acute pancreatitis in 4; all were managed nonoperatively with no mortality. Multisystem organ failure developed in 2 patients, of whom 1 died. There was a significant correlation between intraabdominal complications and prolonged bypass time. The mean bypass time was 96.7 +/- 28.6 minutes for the patients with gastrointestinal complications, compared with 81.7 +/- 48.4 minutes for the whole group (p less than 0.01). No correlation was demonstrated for type of operation undergone or the age of the patient. In the last 5 years, 2,145 patients underwent cardiopulmonary bypass, of whom 562 received pulsatile and 1,583 nonpulsatile flow. The incidence of intraabdominal complications was 0.18% (n = 1) in the pulsatile group compared with 0.63% (n = 10) for the nonpulsatile group (p = 0.14). Intraabdominal complications, although of low incidence, carry a significantly high mortality, and the clinician must be alert in the postoperative period to institute early therapy.

Upper gastrointestinal bleeding following open heart surgery. Predominant finding of aggressive duodenal ulcer disease

We reviewed our experience with endoscopically evaluated severe upper gastrointestinal hemorrhage following open heart surgery. Of 4892 patients undergoing open heart surgery, 18 (0.4%) sustained upper gastrointestinal hemorrhage requiring endoscopic evaluation. Endoscopy identified the source of bleeding in all cases. No significant complications of endoscopy were observed. Duodenal ulcers (DUs) were found in 16 (89%) of cases and were felt to be the source of bleeding in 15 (83%). Aggressive features, such as multiplicity, large size, or distal location were associated with 13 (81%) of the DU cases. Complications necessitated endoscopic or surgical therapy in eight (44%) patients with DUs. We conclude that aggressive DU disease accounts for the majority of severe upper gastrointestinal bleeding following open heart surgery.

[Frequency of pathological changes of the upper gastrointestinal tract in patients awaiting heart surgery]

While waiting for open heart surgery, in 153 patients (104 male, 49 female, 22-76 years of age) without gastrointestinal symptoms and/or history esophago-gastro-duodenoscopy was performed. 124 patients suffered from coronary heart disease, 29 from valvular defect, aneurysm of the sinus of Valsalva or tumor of the heart. In 47.1% endoscopy revealed serious abnormal findings: in 16.3% gastric ulcer, in 20.9% erosive gastritis, duodenal ulcer and erosive duodenitis in 5.2%, respectively, 1 case of gastric carcinoma, 2 of large polyps and 3 of reflux esophagitis of higher degree (totally 3.9%). In patients with coronary artery disease, the relation of erosive and ulcerous gastric lesions as compared with those of duodenal origin was 4:1, in patients with other cardiac diseases it was 2:1, respectively (p less than 0.001). Compared with a normal population, the incidence of pathological gastric findings was 54-fold higher in our patients, and 1.7-fold concerning duodenal lesions, respectively (p less than 0.001). 51 patients on acetylsalicylic acid (160 mg/die) showed pathologic findings in 41.2%, and 96 patients without ulcer-inducing therapy in 51%. Thus, low-dose Aspirin does not seem to have serious gastric side effects. The results of the study stress the necessity of routinely performed endoscopy of the upper gastrointestinal tract in patients awaiting open heart surgery. This will lead to a lower incidence of serious gastrointestinal complications postoperatively which are known to have a high mortality.

Acute postoperative diverticulitis

Acute diverticulitis following surgery is a severe condition reported previously only after heart surgery. Four cases of diverticulitis in the early postoperative period are presented, three of them after non-cardiac procedures (tracheostomy, inguinal hernia repair and laminectomy). Advanced age, administration of morphine, treatment with steroids, postoperative constipation and intestinal mucosal ischaemia are discussed as possible aetiological factors leading to diverticular perforation. Although the diagnosis is often difficult, early treatment offers the best chance of survival.

The acute surgical abdomen after cardiac surgery involving extracorporeal circulation

From 1972 through 1984, 7140 cardiac operations were performed at one university teaching hospital; they were reviewed to elucidate common factors in patients developing an acute surgical abdomen after cardiac surgery and extracorporeal circulation. Twenty-one patients (0.29%) developed an acute surgical abdomen in the period following cardiac surgery. The abdominal surgical complications were, in general, due to complications of peptic ulcer disease, decreased intestinal blood flow, and cholecystitis. There was no correlation between preoperative history, physical examination, cardiac function, laboratory data, and the subsequent development of an acute abdomen. Mortality rate, 24% after abdominal surgery, was increased with emergency cardiac operations, combined cardiac procedures, complications of cardiac surgery, unnecessary delay of abdominal surgery, and abdominal wound complications. Major abdominal wound complications were seen in 38%. Patients undergoing cardiac surgery may develop a variety of common abdominal surgical disorders. Patients so inclined cannot be identified prior to cardiac surgery. Ulcer prophylaxis, wound management, prompt resuscitation, and timely surgery are critical.

Abdominal complications following cardiopulmonary bypass in open-heart surgery

Open-heart surgery was performed on 1686 adult patients between 1980 and 1984, with a mortality rate due to abdominal complications of 0.6%. Every operation involved the use of cardiopulmonary bypass (CPB). Abdominal complications occurred in 1.6%, with an overall mortality rate of 36%. The most frequent complication was gastrointestinal (Gl) bleeding (61%). The mortality of the patients who bled from the Gl tract was 53%. Other complications encountered were gastroduodenal ulcer, colitis, ileus, subphrenic abscess and intraperitoneal bleeding. Prolonged CPB and low output syndrome preceded multiple organ failure, which occurred in 39% of those who had abdominal complications and in 59% of those who bled. Gl bleeding after CPB did not correlate with a previous history of gastric ulcer. Reoperation because of cardiac tamponade or excessive chest tube drainage was a factor predisposing to Gl bleeding. The mortality and abdominal complication rates were significantly higher in valve surgery than in coronary revascularization.

Acute diverticulitis following cardiac surgery

Gastrointestinal complications requiring surgical correction following cardiopulmonary bypass most frequently involve the upper gastrointestinal tract. Surgical diseases of the colon are quite unusual in this setting. We recently performed cardiac surgery on three patients who developed acute diverticulitis requiring laparotomy in the early postoperative period. The presentation and management of this disorder after open heart surgery are discussed.

Hypoperfusion as a possible factor in the development of gastrointestinal complications after cardiac surgery

This study has presented the spectrum of postoperative gastrointestinal system complications after open heart surgery at the University of Washington from 1980 through 1983. The frequent necessity for operative intervention and a mortality rate of 17 percent in our study of gastrointestinal complications in patients who have undergone open heart surgery indicates the need for early diagnosis and treatment. The data suggest that bypass times approaching 100 minutes and the presence of postoperative cardiogenic shock are important risk factors in the development of such complications in elective cardiac surgery patients. An incidence of gastrointestinal complications of 8.6 percent in those undergoing repair of acute aortic dissections makes gastrointestinal complaints particularly suspicious in this subgroup.

General surgical complications after cardiopulmonary bypass surgery

In a single institution, 142 general surgical complications were found in a total of 82 patients after 5,682 cardiac procedures. There were 54 complications in 40 patients within 6 weeks of surgery and 88 complications more than 6 weeks after surgery. There were 12 deaths in the early group and one death in the late group. The incidence of these general surgical complications was low in both the early and late groups (0.9 percent and 1.6 percent, respectively). The mortality rate of general surgical complication within the early group was 23 percent. After 6 weeks the mortality rate was less than 2 percent. Mortality was higher following valve procedures than following coronary artery bypass operations in the early period. Anticoagulation and arrhythmias were both minimal management problems after general surgical operations. The anatomic area most frequently involved was the biliary tract. Documented low cardiac output preceded many of these complications in the early group.