Prevalence and long-term implications of preoperative anemia in patients undergoing elective general surgery: a retrospective cohort study at a university hospital

OBJECTIVE

The aim of this retrospective study was to assess the prevalence of anaemia in a cohort of patients undergoing elective general surgery at a university hospital. Furthermore, the authors investigated the influence of anaemia on short-term and long-term postoperative outcome.

BACKGROUND

Awareness of the negative impact of preoperative anaemia on perioperative morbidity and mortality is rising. Anaemia is a potentially modifiable factor, and its therapy might improve patient outcome in elective surgery. Nevertheless, patients with preoperative anaemia frequently undergo elective surgery without receiving adequate preoperative treatment.

METHODS

In this single-centre cohort study, the authors analyzed 6908 adult patients who underwent elective general surgery. Patients undergoing day-clinic surgery were excluded. In all patients, preoperative haemoglobin concentration and haematocrit was available.

RESULTS

Of all patients analyzed, 32.9% were anaemic (21.0% mild, 11.8% moderate, 1.1% severe). Median time to last follow-up was 5.2 years. During the whole study period, 27.1% of patients died (1.2% died during the hospital stay); median time to death was 1.3 years. Patients with preoperative anaemia had significantly higher mortality rates ( P <0.001) and a higher probability of postoperative complications ( P <0.001). Likewise, receiving blood transfusions was associated with a higher risk of death ( P <0.001).

CONCLUSION

This retrospective single-centre analysis confirmed that preoperative anaemia is common, and is a significant risk factor for unfavourable postoperative outcome. As anaemia is a modifiable risk factor, the implementation of a patient blood management concept is crucial to reduce detrimental postoperative events associated with anaemia.

Incidence and outcomes of AKI in postoperative patients admitted to ICU using full KDIGO criteria - a cohort study

STUDY OBJECTIVE

Acute kidney injury (AKI) is a serious complication in postoperative ICU patients. The incidence of AKI varies substantially based on the type of surgery and definition used. This study focuses on the incidence of AKI in postoperative ICU patients using full KDIGO criteria and related outcomes regarding to different types of surgery.

DESIGN

Retrospective cohort study.

SETTING

Tertiary level university hospital, eight anaesthesiological/surgical ICUs, between 2016 and 2018.

PATIENTS

6261 adult patients.

MEASUREMENTS

Primary outcome was 28-day all-cause mortality in different stages of AKI according to complete KDIGO criteria.

MAIN RESULTS

We found 3497 (55.9%) postoperative ICU patients with AKI. The severity distribution of AKI stage 1 to 3 was 19.7%, 28.4% and 7.8%, respectively, and 235 (4%) patients received RRT. The 28-day mortality was 3% (n = 205). Increasing AKI severity was associated with increased 28-day mortality when adjusted for other variables (AKI 2°: OR 2.81; 95% CI 1.55 to 5.24; p < 0.001 and AKI 3°: OR 11.37.; 95% CI 5.91 to 22.55; p < 0.001). Besides AKI stages 2 and 3, age (OR 1.02; 95% CI 1.01 to 1.04, p < 0.001), NYHA IV (OR 2.23; 95% CI 1.03 to 4.43, p = 0.042), need for surgical reintervention within 48 h (OR 2.92; 95% CI 1.76 to 4.72, p = 0.001), urgent surgery (OR 1.78; 95% CI 1.15 to 2.71, p = 0.01), emergency surgery (OR 2.63; 95% CI 1.58 to 4.31, p = 0.001), vascular surgery (OR 2.01; 95% CI 1.06 to 3.98, p = 0.033), and orthopedic and trauma surgery (OR 3.79; 95% CI 1.98 to 7.09, p < 0.001) versus cardiac surgery was significantly associated with increased risk for 28-days mortality in multivariate analysis.

CONCLUSION

AKI based on full KDIGO criteria is very common in postoperative ICU patients and it is associated with stepwise increase in 28-days mortality.