Zdeněk Šilhart

Vascular Graft Infection - A Single Centre Analysis

Though the frequency of vascular graft infections is very low, its consequences are too serious. The paper aims at the vascular graft infection causes analysis in a single centre. Results achievable by means of several approaches have been discussed and a possible way of lowering the vascular graft infection rate has been tested. Material and methods: A population of 2812 patients having implanted an artificial vascular graft in 2000-2010 were prospectively followed up. Upon the analysis of risk factors, the control group of 653 patients operated on during 2011-2013 were followed up. Results: Number of vascular graft infections was 28 (1,0%). Amputation rate was 19% (5 patients) and the overall mortality 14% (4 patients). Leading signs of the infection were local findings in 88%. All patients with the infection had two or more co-existing independent risk factors picked out by chi-square statistics. It was obesity, repeated interventions and emergency surgery (p<0,001). Gender (men), co-existing infection, diabetes and too long bypass were also significant (p<0,01). There was not MRSA infection at all. After adoption of risk factors reducing approach, there was not proven decreased infection occurrence in patients with implanted artificial grafts. However, during the control period, a higher share of autologous grafts and endovascular methods were used. Thus the overall infection rate was reduced from 0,43 to 0,31%. Conclusion: The graft infection is not a matter of resistant bacteria, but the infection in general. An accumulation of more than two independent risk factors according to local situation should be avoided. As the infection treatment is very demanding with uncertain results, patient’s wish should be taken into account as well. In all primaries, the use of the artificials ought to be minimized and endovascular procedures should be preferred, where appropriate. Emergency surgery should be avoided by in time indication to revascularization.

Myocardial injury in patients after an elective abdominal aortic aneurysm repair

BACKGROUND The aim of the study was to study the frequency of cTnI release in patients undergoing an elective abdominal aortic aneurysm repair (AAA) and examine the relationship between an early perioperative myocardial injury, as detected by an increased serum levels of cTnI, and a clinical outcome (postoperative cardiac and non-cardiac complications, mortality). METHODS A prospective observational study of 90 patients undergoing an elective AAA repair. SETTING University hospital. Blood samples were obtained from 90 patients for cTnI assays, 8 and 24 hours after surgery. RESULTS 74.5 % of patients faced a high and medium perioperative risk (ASA III-IV). Peak postoperative cTnI concentrations above the lower detection limit of the immunoassay occurred in 22 patients. 15 of these patients (cTnI levels: 0.2-10.2 ng/ml) displayed symptoms of clinically significant complications. 9 patients (cTnI levels: 0.48-10.2 ng/ml) had serious complications (3x MI, 3x heart failure, 2x bronchopneumonia - respiratory failure, 1x sepsis), one patient died. Only 5.8 % of patients without cTnI increase had postoperative complications. A Chi-square analysis revealed a significant association between cTi elevation and postoperative complications (chi-square 38.737, p<0.0001). CONCLUSIONS A quarter of the patients who underwent an elective aortic surgery suffered from myocardial necrosis. A cTnI rise was associated with clinically significant events in 68 %; patients with cTnI release were at a significantly higher risk of cardiac and non-cardiac complications. These data confirm that patients with a postoperative rise in cTnI levels would be classified as patients at a higher risk of complications and a specific cardioprotective treatment, invasive monitoring and a longer ICU stay could be required in these cases (Tab. 6, Ref. 24).

Perioperative haemodynamic monitoring by oesophageal Doppler improves outcome of patients with abdominal aortic aneurysm repair

BACKGROUND AAA repair is associated with high rate of mortality and morbidity. Oesophageal Doppler (OED) can offer a less invasive cost-effective tool for intraoperative monitoring of haemodynamic changes. The aim of the study was to confirm the benefits of haemodynamic optimisation in patients undergoing AAA repair using OED monitoring. We assumed that haemodynamic parameters of patients with OED would be better optimised; they would probably get more fluids during the operation, and their ICU and hospital stay would be shorter as a result of having fewer postoperative complications and lower mortality. METHODS Seventy patients (Doppler group) who underwent AAA operation in 2003-2008 were matched with 70 patients (control group) operated on AAA in 1998-2002. OED was used to estimate the cardiac output, its variations and fluid management. The administered fluids, length of ICU and hospital stay, frequency of postoperative complications and mortality were compared in Doppler and control groups (Mann-Whitney test, Fishers exact test). RESULTS No statistically significant difference was found in preoperative parameters. The Doppler group was administered significantly more crystalloids (p<0.001), colloids (p<0.001), sum-up of fluids (4000 ml vs. 3000 ml; p<0.001) in the perioperative period. The Doppler group had a lower incidence of major serious complications (8 vs. 21; p=0.034) and shorter ICU (4 vs. 6 days; p<0.001) and hospital stay (10 vs. 11 days; p=0.012). CONCLUSIONS The haemodynamic monitoring by oesophageal Doppler can improve the outcome of patients with AAA repair (fewer major complications, shorter ICU and hospital stay) (Tab. 4, Fig. 4, Ref. 25).