ABSTRACT
BACKGROUND: Efforts to determine the suitability of low-grade pancreatic injuries for nonoperative management have been hindered by the inaccuracy of older computed tomography (CT) technology for detecting pancreatic injury (PI). This retrospective, multicenter American Association for the Surgery of Trauma-sponsored trial examined the sensitivity of newer 16- and 64-multidetector CT (MDCT) for detecting PI, and sensitivity/specificity for the identification of pancreatic ductal injury (PDI). METHODS: Patients who received a preoperative 16- or 64-MDCT followed by laparotomy with a documented PI were enrolled. Preoperative MDCT scans were classified as indicating the presence (+) or absence (-) of PI and PDI. Operative notes were reviewed and all patients were confirmed as PI (+), and then classified as PDI (+) or (-). As all patients had PI, an analysis of PI specificity was not possible. PI patients formed the pool for further PDI analysis. As sensitivity and specificity data were available for PDI, multivariate logistic regression was performed for PDI patients using the presence or absence of agreement between CT and operative note findings as an independent variable. Covariates were age, gender, Injury Severity Score, mechanism of injury, presence of oral contrast, presence of other abdominal injuries, performance of the scan as part of a dedicated pancreas protocol, and image thickness < or =3 mm or > or =5 mm. RESULTS: Twenty centers enrolled 206 PI patients, including 71 PDI (+) patients. Intravenous contrast was used in 203 studies; 69 studies used presence of oral contrast. Eight-nine percent were blunt mechanisms, and 96% were able to have their duct status operatively classified as PDI (+) or (-). The sensitivity of 16-MDCT for all PI was 60.1%, whereas 64-MDCT was 47.2%. For PDI, the sensitivities of 16- and 64-MDCT were 54.0% and 52.4%, respectively, with specificities of 94.8% for 16-MDCT scanners and 90.3% for 64-MDCT scanners. Logistic regression showed that no covariates were associated with an increased likelihood of detecting PDI for either 16- or 64-MDCT scanners. The area under the curve was 0.66 for the 16-MDCT PDI analysis and 0.77 for the 64-MDCT PDI analysis. CONCLUSION: Sixteen and 64-MDCT have low sensitivity for detecting PI and PDI, while exhibiting a high specificity for PDI. Their use as decision-making tools for the nonoperative management of PI are, therefore, limited.
Subject(s)
Pancreas/injuries , Tomography, Spiral Computed/instrumentation , Wounds, Nonpenetrating/diagnostic imaging , Wounds, Penetrating/diagnostic imaging , Administration, Oral , Adolescent , Adult , Contrast Media/administration & dosage , Female , Humans , Infusions, Intravenous , Injury Severity Score , Laparotomy , Male , Middle Aged , Pancreas/surgery , Pancreatic Ducts/diagnostic imaging , Pancreatic Ducts/injuries , Pancreatic Ducts/surgery , Retrospective Studies , Sensitivity and Specificity , United States , Wounds, Nonpenetrating/surgery , Wounds, Penetrating/surgery , Young AdultABSTRACT
PURPOSE OF THE STUDY: Atrial fibrillation after cardiac surgery is still a frequent encountered complication and has been associated with increased hospital length of stay and numerous postoperative complications. The pathogenesis of atrial fibrillation involves an overall sequence of perioperative events, collectively termed as ischemia-reperfusion injury. Heat-shock proteins have been found to provide increased protection during ischemia-reperfusion as well as increased postischemic cardiac functional recovery. We sought to determine whether preoperative atrial heat shock levels were correlated with the appearance of postoperative atrial fibrillation. BASIC METHODS: Preoperative atrial myocardial samples obtained just before cannulation from 101 patients were used to detect immunohistochemically the expression of heat-shock proteins. The derived results were compared statistically with the incidence of postoperative atrial fibrillation, its time of appearance, duration and resistance to administered antiarrhythmics. PRINCIPAL FINDINGS: The overall incidence of postoperative atrial fibrillation was 22.3%. Of these patients, 58.3% had no detectable heat shock proteins in their cytoplasm, in sharp contrast with 100% of the patients with no atrial fibrillation who were positive for heat shock proteins (p<0.01). Four percent of our patient group had prolonged atrial fibrillation (defined as duration >48 h). These patients had significantly less (p<0.01) nuclear heat shock protein expression compared with the non-atrial fibrillation group. However, the difference of the heat shock protein expression between the prolonged atrial fibrillation and the rest of the atrial fibrillation patients was not significant (p=0.891). CONCLUSIONS: Our results indicate that patients with low preoperative atrial heat shock protein expression have a significantly greater incidence of postoperative atrial fibrillation. Heat shock protein expression did not, however, correlate with the onset of atrial fibrillation and the resistance to administered medications. Heat shock protein preoperative induction as a measure of myocardial preconditioning may potentially decrease the incidence of postoperative atrial fibrillation.
