Outcomes of Patient Blood Management in Severely Anemic Patients

The goal of this observational cohort study is to compare patients with very low red blood counts who receive different therapy. Its main question\[s\] it aims to answer are:

* Which group of patients dies more frequent: Patients who receive patient blood management only, patients who receive patient blood management and transfusions or patients who receive only transfusions?
* Among these groups: which group of patients has more complications during hospital stay? Patients will either receive patient blood management, which is the management of anemia, bleeding and coagulation problems, will receive transfusions, that is, blood from other people, or a mix of both.

Background:

There seems to be a clear relationship between hemoglobin level and inhospital morbidity and mortality. To mitigate negative effects of lower hemoglobin levels, that is, anemia, transfusions are given when the hemoglobin level of the patient reaches a point deemed detrimental by the treating health care personnel. Patient Blood Management (PBM) adds to the armamentarium of anemia therapy, starting typically well before transfusions are given, and sometimes beyond this point. PBM utilizes medical strategies to enhance the patients own red cell mass and to alleviate the ill effects of disease and bleeding on hematopoesis and homeostasis.

Objective:

The objectives of the present study is to investigate the effects of 2 different management strategies of severe anemia, namely PBM exclusively or PBM with transfusion therapy, and compare them to standard transfusion therapy as regards inhospital mortality and morbidity.

Hypothesis: It is hypothesized that severely anemic participants who received a combination of PBM and restrictive transfusion regime would have a lower mortality and less complications than participants receiving a liberal transfusion therapy without PBM, while participants not being transfused at all will have increased mortality and morbidity.

Setting: The study will be performed at HELIOS Klinikum Gotha (HKG) and Helios Klinikum Erfurt (HKE) which are two neighboring hospitals with overlapping personnel, purchasing, IT departments and standard operating procedures. Both hospitals offer basic, advanced and specialist care to their communities. HKG offers PBM to their patients, while HKE does not.

Data sources: Data will be sourced from the hospital information systems of HKG and HKE.

Diseases are coded with the ICD-10-GM (International Code of Diseases, Version 10, Germany) and procedures using the OPS code (Procedure Key, analogous to the International Code of Procedures).

Participants: All adult patients treated between 1.6.2008 and 31.12.2020 in HKG and HKE will be eligible for enrollment when they were treated by a specialty that both hospitals offer and suffer from severe anemia, defined as a nadir hemoglobin of \< 8 g/dL.

Interventions:

Study group 1: Participants in this group received full PBM measures as clinically appropriate, but were not transfused at all.

Study group 2: Participants in this group received convenience measures of PBM and were transfused as deemed necessary in an environment where a restrictive transfusion strategy is encouraged.

Control:

The control group was treated without systematic PBM offered to patients and transfusions were the only standard of care for severely anemic patients.

Outcome:

Primary outcome is inhospital mortality. Secondary outcomes are morbidity measures, such as acute myocardial infarction, blood stream infection, cerebrovascular accident, transfusion complications, readmission rates, etc.

Study design:

This is a dual-center, retrospective observational cohort study. Reporting of results will be performed in line with the REporting of studies Conducted using Observational Routinely-collected health Data (RECORD) statement extension of the STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement.

The study will be guided by a study protocol with an attached statistical analysis plan.

Eligibility Criteria:
Inclusion Criteria:

* adult
* nadir hemoglobin \< 8 g/dL

Exclusion Criteria:

* treatment in a non-comparable specialty
* transfer from hospital in the first 6 h after arrival
* requesting PBM / transfusion-free therapy but not offered