Electronic crossmatch is not available in all United Kingdom hospitals potentially leading to a large number of manual serological crossmatches relative to the number of red cell units actually transfused. In 2011 it was observed that there was a high Red Cell crossmatch to transfusion ratio (C:T ratio) at a large London teaching hospital (St George’s Healthcare NHS Trust serves a population of 1.3 million across South West London and includes services such as cardiothoracic surgery, and renal transplantation).

An initial activity to reduce the C:T ratio was the introduction of a Maximum Surgical Blood Ordering Schedule (MBOS) that gives pre-operative guidance on how many red cell units should be crossmatched for each procedure. Over corresponding 5 month periods in 2011 and 2012 there was a decrease of 200 units ordered pre-operatively, and a drop in C:T ratio from 5:1 to 4:1. There was also a decrease in the ordering of red blood cell stock of 200 units/month which equates to a cost saving of £24,600 (US$ 41,532) per month.

Re-audit in 2014 showed the improved C:T ratio was maintained but still too high at 4:1. A survey showed a lack of awareness of the MBOS, poor access to the MBOS because it is buried in an Intranet with large amounts of content, and 28% pre-operative anaemia. Furthermore, strict limits on junior doctor working hours led to loss of continuity of care with blood test results not being looked at in a timely manner, potentially leading to unnecessary transfusion. This was discussed at the London Regional Transfusion Committee (RTC) (with members from 90 hospitals) and it was agreed that a smartphone Application (‘App’) would stimulate further improvement.


Two RTC members and one St George’s representative jointly developed an iOS App called ‘MBOS Master’. Significant time was spent writing a detailed software specification to clarify the required functions of the App and how these functions would operate. Subsequently a prototype was demonstrated to key stakeholders, including staff in the pre-operative clinics and the London RTC through its regular meetings.


Stakeholder feedback was used to improve the user interface and functionality. Comments were made about the convenience of the MBOS in this format for both clinical and laboratory teams, how it would support communication between the different areas, and allow consistency of information to users. Improvements were made to the display of information to increase visibility of essential information. MBOS Master was enhanced by the addition of functions that support the handover of a list of blood tests taken pre-operatively (hopefully to improve continuity of care).

MBOS Master allows:

  1. The RTC to send messages to all MBOS Master users within the region, such as blood product warnings, and upcoming meetings

  2. The local hospital to upload its own customised MBOS just for users within that hospital

  3. The local hospital to upload information that is tailored to its local users, such as important phone numbers, and hospital transfusion committee meetings

  4. Easy navigation of the MBOS with the opportunity for individual users to store a Favorites list of frequently used recommendations

  5. The user to make multiple lists of patient hospital numbers and set reminders to chase results of pending blood tests, or to email the lists to colleagues.


This project illustrates the importance of clearly defining the aim and functions of an App methodically, hands on development of the App by health professionals who are in touch with day to day transfusion practice, and the iterative process of testing with future users to maximise the ease of use and functionality of an App for healthcare purposes.

The pre-release version is undergoing further testing by key stakeholders and is anticipated to be available in autumn 2014 through Apple’s App Store, with an Android version soon to follow. Ordering of red cells in relation to the MBOS will be reaudited 6 months after the App is launched to assess its impact on C:T ratio.

In future the App will be assessed in terms of impact on the C:T ratio, blood stocks, and early treatment of pre-operative anemia.


No relevant conflicts of interest to declare.

Author notes


Asterisk with author names denotes non-ASH members.