Visual analytical tool for evaluation of 10-year perioperative transfusion practice at a children's hospital

Abstract

Children are a vulnerable population in the operating room, and are particularly at risk of complications from unanticipated hemorrhage. The decision to prepare blood products prior to surgery varies depending on the personal experience of the clinician caring for the patient. We present the first application of a data visualization technique to study large datasets in the context of blood product transfusions at a tertiary pediatric hospital. The visual analytical interface allows real-time interaction with datasets from 230 000 procedure records. Clinicians can use the visual analytical interface to analyze blood product usage based on procedure- and patient-specific factors, and then use that information to guide policies for ordering blood products.

Keywords: anesthesiology; clinical decision support; maximum surgical blood order schedule; pediatric; transfusion; visual analytics.

Figure 1

The American Society of Anesthesiologists (ASA) physical status categories describe patients as: (1) healthy (n1=63 315; n1E=4521); (2) mild systemic disease (n2=89 524; n2E=4430); (3) severe systemic disease (n3=56 459; n3E=3805); (4) severe systemic disease that is a constant threat to life (n4=6306; n4E=1943); (5) moribund, not expected to survive without surgery (n5=65; n5E=263); (6) declared brain dead, organ donor (n6=15; n6E=19)¹⁵. The ‘E’ modification indicates emergency surgery. We used the ASA physical status as a primary filter to identify patients who received blood transfusions within each ASA group. The incidence and proportion of patients receiving blood transfusions at each classification increases with severity of disease and emergency surgery.

Figure 2

The user interface allows selection of any number of filters. The ‘Transfusion’ section denotes patients who received any blood product or patients who did not receive any blood products during surgery. The ‘Age Grouper’ allows selection of predefined age categories. The ‘ASA Status’ allows selection of any American Society of Anesthesiologists (ASA) classification. The ‘Oper. Room Area’ allows selection of procedures based on the location within the hospital. On the right side of the screen, the ‘DX’ code represents the International Classification of Disease (ICD)-9 codes and the ‘CPT (Current Procedural Terminology) Description’ allows selection of specific procedures. Both the DX and CPT sections allow free-text search. The histograms displayed represent data distribution of individual variables. The vertical lines represent the average (red) and 1SD (gray). The top left histogram represents weight, top right is age in days, bottom left is the total blood product volume transfused in mL divided by the patient's weight (mL/kg), and the bottom right represents the surgery time (in min). The histograms update automatically when filters are applied.

Figure 3

A real use case based on a clinical inquiry for transfusion requirements for neonates and infants younger than 6 months undergoing resection of a sacrococcygeal teratoma. This condition is usually present at birth and typically requires large transfusion volumes. The initial Current Procedural Terminology (CPT) filter retrieved 43 patients (age 0 days to 6 months), of which 21 received blood transfusions. The mean (SD) weight for the patients in this selection was 3.1 (1.4) kg, age was 19 (39.7) days, and transfusion requirement was 43.9 (81.20) mL/kg. For reference, the circulating blood volume in a term newborn is ∼90 mL/kg. ICD, International Classification of Disease.