The impact of intravenous iron supplementation in elderly patients undergoing major surgery.

BACKGROUND: Age and preoperative anaemia are risk factors for poor surgical outcome and blood transfusion. The aim of this study was to examine the effect of iron supplementation in iron-deficient (ID) elderly patients undergoing major surgery. METHOD: In this single-centre observational study, patients ≥ 65 years undergoing major surgery were screened for anaemia and ID. Patients were assigned to the following groups: A- (no anaemia); A-,ID+,T+ (no anaemia, iron-deficient, intravenous iron supplementation); A+ (anaemia); and A+,ID+,T+ (anaemia, iron-deficient, intravenous iron supplementation). RESULTS: Of 4,381 patients screened at the anaemia walk-in clinic, 2,381 (54%) patients were ≥ 65 years old and 2,191 cases were included in analysis. The ID prevalence was 63% in patients with haemoglobin (Hb) < 8 g/dl, 47.2% in patients with Hb from 8.0 to 8.9 g/dl, and 44.3% in patients with Hb from 9 to 9.9 g/dl. In severely anaemic patients, an Hb increase of 0.6 (0.4; 1.2) and 1.2 (0.7; 1.6) g/dl was detected with iron supplementation 6-10 and > 10 days before surgery, respectively. Hb increased by 0 (-0.1; 0) g/dl with iron supplementation 1-5 days before surgery, 0.2 (-0.1; 0.5) g/dl with iron supplementation 6-10 days before surgery, and 0.2 (-0.2; 1.1) g/dl with supplementation > 10 days before surgery (p < 0.001 for 1-5 vs. 6-10 days). Overall, 58% of A+,ID+,T+ patients showed an Hb increase of > 0.5 g/dl. The number of transfused red blood cell units was significantly lower in patients supplemented with iron (0 (0; 3)) compared to non-treated anaemic patients (1 (0; 4)) (p = 0.03). Patients with iron supplementation > 6 days before surgery achieved mobility 2 days earlier than patients with iron supplementation < 6 days. CONCLUSIONS: Intravenous iron supplementation increases Hb level and thereby reduces blood transfusion rate in elderly surgical patients with ID anaemia.

Definition of acute kidney injury impacts prevalence and prognosis in ACS patients undergoing coronary angiography.

BACKGROUND: Development of acute kidney injury (AKI) in invasively managed patients with acute coronary syndrome (ACS) is associated with a markedly increased mortality risk. Different definitions of AKI are in use, leading to varying prevalence and outcome measurements. The aim of the present study is to analyze an ACS population undergoing coronary angiography for differences in AKI prevalence and outcome using four established AKI definitions. METHODS: 944 patients (30% female) were enrolled in a prospective registry between 2003 and 2005 with 6-month all-cause mortality as outcome measure. Four established AKI definitions were used: an increase in serum creatinine (sCR) ≥ 1.5 fold, ≥ 0.3 mg/dl, and ≥ 0.5 mg/dl and a decrease in eGFR > 25% from baseline (AKIN 1, AKIN 2, CIN, and RIFLE definition groups, respectively). RESULTS: AKI rates varied widely between the different groups. Using the CIN definition, AKI frequency was lowest (4.4%), whereas it was highest if the RIFLE definition was applied (13.2%). AKIN 2 displayed a twofold higher AKI prevalence compared with AKIN 1 (10.2% vs. 5.3% (p < 0.001)). AKI was a strong risk factor for mid-term mortality, with distinctive variability between the definitions. The lowest mortality risk was found in the RIFLE group (HR 6.0; 95% CI 3.7-10.0; p < 0.001), whereas CIN revealed the highest risk (HR 16.7; 95% CI 9.9-28.1; p < 0.001). CONCLUSION: Prevalence and outcome in ACS patients varied considerably depending on the AKI definition applied. To define patients with highest renal function-associated mortality risk, use of the CIN definition seems to have the highest prognostic relevance.