Perioperative Cardiac Damage in Vascular Surgery Patients

BackgroundPatients undergoing vascular surgery are at increased risk for developing cardiac complications. Majority of patients with perioperative myocardial damage are asymptomatic. Our objective is to review the available literature addressing the prevalence and prognostic implications of perioperative myocardial damage in vascular surgery patients.MethodsAn Internet-based literature search was performed using MEDLINE to identify all published reports on perioperative myocardial damage in vascular surgery patients. Only those studies published from 2000 to 2010 evaluating myocardial damage using troponin I or T, with or without symptoms of angina pectoris were included.ResultsThirteen studies evaluating the prevalence of perioperative myocardial ischaemia or infarction were included in the study. The incidence of perioperative myocardial ischaemia ranged from 14% to 47% and the incidence of perioperative myocardial infarction ranged from 1% to 26%. In addition, 10 studies evaluating the prognostic value of perioperative myocardial ischaemia towards postoperative mortality or the occurrence of major adverse cardiac events were included. In the retrieved studies, hazard ratios varied from 1.9 to 9.0.ConclusionThe high prevalence and asymptomatic nature of perioperative myocardial damage, combined with a substantial influence on postoperative mortality of vascular surgery patients, underline the importance of early detection and adequate management of perioperative myocardial damage.This article provides an extended overview regarding the prevalence and prognostic value of perioperative myocardial ischaemia and infarction in vascular surgery patients. In addition, treatment options to reduce the risk of perioperative myocardial damage are provided based on the current available literature.     

Renal Function After Cardiac Surgery: Adverse Effect of Furosemide

Renal failure is a frequent event after cardiopulmonary by-pass. Hemodynamic alterations that occur during surgery, as well as factors depending on the host, are the main risk factors for renal dysfunction. To evaluate the frequency and risk factors for renal dysfunction in this setting, a cohort of fifty patients with preoperative serum creatinine under 1.5 mg/dL, submitted to cardiac surgery with cardiopulmonary by-pass was analyzed. Variables related to preoperative patient condition, intraoperative and postoperative periods were recorded. Renal function was assessed by clearances of creatinine, urea and free water, also by fractional excretion of sodium (FENa), at baseline, at anesthetic induction and during postoperative period. Patients were arbitrarily divided in two groups, according to the serum creatinine (S_Cr) value at the end of the postoperative period: Group I: S_Cr <2 mg/dL (n = 44 patients (88.5%)) and Group II: S_Cr >2 mg/dL (n = 6 patients (11.5%)). A decrease of renal function was observed in all patients: creatinemia raised from 1.04 ± 0.2 to 1.55 ± 0.4 mg/dL (33%), associated with a rise in FENa. Differences between group I and group II using univariate analysis were: baseline serum creatinine (1.01 ± 0.23 mg/dL vs. 1.26 ± 0.19 mg/dL, p = 0.03), FENa (0.99 ± 0.8 vs. 2.2 ± 2.1, p = 0.04), furosemide dose during surgery normalized to body surface area (93.2 ± 23 mg/1.73 m² BSA vs. 135 ± 38 mg/1.73 m² BSA, p<0.001), and hemodilution index (17.3 ± 4.3% vs. 22.8 ± 3.2%, p<0.01). In the multiple regression model, baseline creatinemia and furosemide dose were associated to renal dysfunction.     

Perioperative Short-Term Outcome in Super-Super-Obese Patients Undergoing Bariatric Surgery

Background

Prevalence of obesity is increasing with a pandemic magnitude worldwide. Incidence of super-super-obesity (>?60 kg/m²) is expanding by the same means. While bariatric surgery is the only approach with proven long-term results, surgical outcome in super-super-obesity is still discussed controversially.

Objective

This retrospective study examined bariatric surgery patients’ short-term outcome in relation to their degree of obesity.

Setting

Data collection was performed in a German university medical center between March 2010 and November 2013.

Methods

This study analyzes a cohort of 715 patients in a single institution. Patients were subdivided into three groups, obese (≤?49.9 kg/m²), super-obese (≥?50 kg/m²), and super-super-obese (≥?60 kg/m²), and evaluated regarding perioperative outcome.

Results

Three hundred eighty-one patients were included into obese (O); 225 patients, into super-obese (SO); and 109 patients, into super-super-obese (SSO) cohort. There were no significant differences regarding patient characteristics including quantity of comorbidities and perioperative outcome. BMI was significantly lower in patients with complications, compared to patients without complications (p?<?0.05), whereas patients’ age was significantly higher (p?<?0.05) in complication cohort. One SSO patient died of a septic multiorgan failure. Thus, the 30-day overall mortality was 0.14%. The BMI showed an inverse correlation to the patients’ age at surgery (p?<?0.05).

Conclusion

Super-super-obesity should not be considered as a limiting factor for bariatric surgery outcome; however, the patients’ age, surgeries prior to the bariatric procedure, and comorbidities must be considered prior to bariatric surgical treatment.

     

N-Terminal Pro-brain Natriuretic Peptide Identifies Patients at High Risk for Adverse Cardiac Outcome after Vascular Surgery

Background: Preoperative N-terminal pro-BNP (NT-proBNP) is independently associated with adverse cardiac outcome but does not anticipate the dynamic consequences of anesthesia and surgery. The authors hypothesized that a single postoperative NT-proBNP level provides additional prognostic information for in-hospital and late cardiac events.

Methods: Two hundred eighteen patients scheduled to undergo vascular surgery were enrolled and followed up for 24-30 months. Logistic regression and Cox proportional hazards model were performed to evaluate predictors of in-hospital and long-term cardiac outcome. The optimal discriminatory level of preoperative and postoperative NT-proBNP was determined by receiver operating characteristic analysis.

Results: During a median follow-up of 826 days, 44 patients (20%) experienced 51 cardiac events. Perioperatively, median NT-proBNP increased from 215 to 557 pg/ml (interquartile range, 83/457 to 221/1178 pg/ml; P < 0.001). The optimum discriminate threshold for preoperative and postoperative NT-proBNP was 280 pg/ml (95% confidence interval, 123-400) and 860 pg/ml (95% confidence interval, 556-1,054), respectively. Adjusted for age, previous myocardial infarction, preoperative fibrinogen, creatinine, high-sensitivity C-reactive protein, type, duration, and surgical complications, only postoperative NT-proBNP remained significantly associated with in-hospital (adjusted hazard ratio, 19.8; 95% confidence interval, 3.4-115) and long-term cardiac outcome (adjusted hazard ratio, 4.88; 95% confidence interval, 2.43-9.81).