Imaging of abdominal complications following cardiac surgery

Acute bowel ischemia after heart operations

Acute bowel ischemia is a perioperative complication that is frequently unrecognized as a cause of death after cardiac surgical procedures, with an in-hospital mortality of 50% to 100%. In recent years, controversy regarding the most appropriate approach to resolve clinical or laboratory suspicion and the limited therapeutic options have led to very little improvement in patient prognosis. This article reviews the related literature examining the actual prevalence, pathophysiologic mechanisms, predisposing factors, diagnostic tests, and therapeutic approaches providing a glance at new promising tools in diagnostic workup.

Iatrogenic Injury to the Spleen—CT Appearance

Splenic injury is a well-known but rare complication of various abdominal surgical and invasive procedures, and even of cardiac surgery. The true incidence of iatrogenic splenic trauma is, however, difficult to assess and is probably underestimated. Overt injuries diagnosed during surgery are usually immediately treated by splenectomy without imaging. This review focuses on missed splenic injuries that are diagnosed on imaging following surgery or an invasive procedure.

Risk factors and outcomes of pancreatitis after open heart surgery

BACKGROUND

We sought to analyze the risk factors and natural history associated with post-cardiac surgery acute pancreatitis.

METHODS

Retrospective analysis of all patients having undergone cardiac surgery at our hospital between January 1, 1992, and October 1, 2001.

RESULTS

A total of 10,249 cardiac operations were performed. Thirty-nine (0.4%) patients developed postoperative pancreatitis. There was a higher incidence during the period spanning 1992 through 1996 than 1997 through 2001 (0.6% versus 0.2%, P< .05). Patients with pancreatitis had longer postoperative length of stay (51+/-5 days versus 10+/-1 days, P<.05) and a greater in-hospital mortality rate (28% versus 4%, P<.05) than patients who did not develop pancreatitis. A history of alcohol abuse, cardiac surgery performed during 1992 to 1996, increased cardiopulmonary bypass time, and increased cross-clamp time were independent risk factors for the development of pancreatitis. Multiple-organ failure was an independent predictor for death among patients with pancreatitis.

CONCLUSIONS

Although the frequency of post-cardiac surgery pancreatitis is diminishing, it is still associated with significant mortality.

Accuracy of diagnostic laparoscopy for early diagnosis of abdominal complications after cardiac surgery

BACKGROUND

In the early postoperative period after major cardiac surgery using extracorporal circulation, abdominal complications can have serious consequences with a mortality rate of up to 70%. Early diagnosis and the timely institution of therapy are the most important factors to improve the outcome; however, clinical evaluation of the abdomen is difficult in these patients. Diagnostic laparoscopy is a minimally invasive procedure with low procedure-associated morbidity, even in critically ill patients. The aims of our study were to investigate the safety of laparoscopy in critically ill patients suspected to have intraabdominal pathology following cardiac surgery and to evaluate the accuracy of diagnostic laparoscopy compared to laparotomy in this setting.

METHODS

A total of 17 patients were included (13 male, four female, age 52-80 years) in the early (3-30 days) postoperative period after cardiac surgery using extracorporal circulation (10 ACVB, four valve replacement, one aorto-coronary-venous-bypass (ACVB)+ valve replacement, two cardiac transplantation). Clinical and laboratory findings included distended abdomen (17 of 17), elevated white blood cells (12 of 17), elevated C-reactive protein (CRP) (13 of 17), and elevated lactate levels (11 of 17). The decision to perform laparotomy was taken in all patients on the basis of their clinical condition. Diagnostic laparoscopy was always performed immediately before laparotomy. The laparoscopic findings were then compared to the laparotomy findings.

RESULTS

In one patient, laparoscopy showed no abnormal findings, this was confirmed on laparotomy. Five patients were found to have massive distension of the large bowel without ischemia on both laparoscopy and laparotomy. Colonic ischemia of the right hemicolon was found laparoscopically in six patients, which was confirmed in all cases by open resection and histological workup. Three patients suffered from acute cholecystitis, which was correctly diagnosed by laparoscopy in all cases. In one patient, laparoscopy revealed fibrinous peritonitis without other findings. Open exploration failed to identify the cause of the peritonitis in this patient. Laparoscopy showed no pathological findings in one patient, but laparotomy then revealed necrotizing pancreatitis confined to the lesser sac. There was one laparoscopy-associated intraoperative complication (6%) in this series.

CONCLUSIONS

Diagnostic laparoscopy is a minimally invasive procedure that can be performed at low intraoperative risk in critically ill patients and has a high sensitivity (94%) for the correct diagnosis of intraabdominal complications after major cardiac surgery. These results suggest that bedside laparoscopy should be considered for all patients with equivocal abdominal symptoms in this setting.

Unexpected subdiaphragmatic findings on CT of the chest in septic patients after cardiac surgery

AIM

to draw the attention to upper abdominal abnormalities, which may be revealed incidentally in patients referred for a chest computed tomography (CT) after cardiac surgery.

MATERIALS AND METHODS

We reviewed prospectively and retrospectively the CT results of all patients referred for a chest CT, with suspected sternal infection or for other reasons, after cardiac surgery, to assess possible upper abdominal disease as visualized on lower cuts of the chest CT with abdominal windows.

RESULTS

Out of a total of 205 patients in the study 39 (19%) had unexpected abdominal abnormalities. The organs involved in decreasing order of frequency were the spleen (n = 18), gallbladder (n = 15), pancreas (n = 9), kidneys (n = 6) and bowel (n = 3). Many patients had involvement of more than one organ. The lesions were mainly ischaemic and/or infectious in origin. These findings led to interventional procedures in 13 (33%) of the patients with a good outcome.

CONCLUSIONS

We found a relatively high prevalence of abdominal abnormalities on CT of the chest in patients referred with suspected thoracic problems after cardiac surgery. Major findings on CT led to changes in the management of these patients. We recommend therefore viewing lung bases with abdominal windows as well as adding sections through the upper abdomen in patients who are referred for a chest CT after cardiac surgery with suspected thoracic problems.

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.