Blood and blood product transfusion practices in critically ill patients: A prospective observational study

Introduction

Transfusion of blood and blood products is a common intervention in the intensive care unit (ICU). In the face of haemodynamic instability, anaemia, coagulopathy, or bleeding, the decision to transfuse is often made in real time. However, variability exists in practicedue to differing patient-specific factors, availability of blood products, and clinician preferences. Critically ill patients often develop anaemia due to frequent blood sampling, underlying inflammation, and bleeding, increasing the likelihood of transfusion.

Various authors have reported inconsistent adherence to the currently available evidence-based guidelines.

While blood products can be life-saving, their use may contribute to adverse outcomes, increased length of ICU stay, and complications such as transfusion reactions, volume overload, and immunomodulation. Evaluating current practices through the lens of thresholds and clinical reasoning is essential to identify the gaps between evidence and clinical practice.

This study aims to assess blood and blood product transfusion practices in the ICU setting, with focus on component-specific utilisation, thresholds and reasons for transfusion.

Research question

Blood and blood product transfusion practices in the ICU in terms of thresholds and reasons for the same

P: All adult patients admitted to the Main ICU

E: Blood and/or blood product transfusion

O: Thresholds and reasons for the decision to transfuse

T: Duration of ICU stay

Objectives

Primary outcome: Thresholds and reasons for transfusion of various blood products.

Secondary outcomes:

Consistency of transfusion practices with available guidelines.

Association of transfusion with clinical outcomes (LOS in ICU, days of mechanical ventilation, requirement of RRT, vasopressor requirement, ICU mortality) and TRALI and TACO (as diagnosed by the clinical team).

Incidence of anaemia in critically ill patients. (Hb 12-14gm/dl for females and 14-16gm/dl for males)

Average Hb in critically ill patients adjusted for the number of PRBC units transfused and duration of ICU stay.

Volume of blood sampled each day (routine and on-demand) and its correlation with the incidence of anaemia.

Frequency of reports of laboratory investigations (Hmg and coagulogram) within normal range.

 Study Design: Prospective, observational study

Setting: Main ICU, PGIMER, Chandigarh

Duration Of Study: One year from date of Ethics Committee approval and CTRI registration (200 patients)

Inclusion criteria: All adult patients admitted to Main ICU will be enrolled on the day of admission. These will be the medically critically ill patients.

Exclusion Criteria:

Patients with duration of stay < 48 hours

Patients with known haemotological disorder (malignancy etc.)

Refusal to participate

 Methodology

Data Collection:

Baseline parameters

Demographic data (age, gender, body weight, height)

Provisional diagnosis

APACHE II score on Day 1

Charlson Comorbidity index (CCI)

SOFA score on Day 1

Daily Hb and coagulogram

Transfusion-related data

Blood and blood product transfusion: day of admission

Type and volume of blood product transfused

Threshold and reason for transfusion

Day-wise blood sampling volume (routine or on-demand)

Use of haematinics/iron/EPO (daily)

Any bleeding episode

Normal reports of laboratory investigations (haemogram and coagulogram)

Clinical outcome data

Length of stay (LOS) in ICU

Days of mechanical ventilation

Daily number of inotropes

Requirement of renal replacement therapy (RRT)

ICU mortality

LOS in hospital

In-hospital mortality

 Sample size calculation:

In the previous year, the Main ICU admitted 326 patients. We plan to recruit 200 patients consecutively over the duration of the study (1 year).

Data Analysis:

Descriptive analysis will be done, the categorical variables will be expressed as frequencies and percentages, and continuous variables will be expressed as mean ± SD or median and Inter-quartile range.

Predefined subgroups identified will be patients undergoing transfusion or not, according to each blood product, patient comorbidity profile and organ dysfunction at the time of admission.

Comparison between various subgroups will be done using t-test, Fisher’s exact test, Mann-Whitney test, etc., as appropriate.