Routine Blood Tests in Paediatric Intensive Care Unit ( PICU ) - Standard Operating Procedure

Publication: 18/11/2014  
Next review: 01/01/2025  
Standard Operating Procedure
ID: 4030 
Approved By: Trust Clinical Guidelines Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2022  


This Standard Operating Procedure is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.

Routine Blood Tests in PICU

Every Drop Counts

Children in PICU do need blood tests, but not all of them need all tests every day!

Please follow this decision making tool and think if the result of the test is going to influence the management of the patient.

This tool has helped us reduce the cost and number of blood tests by nearly 20%. This can save £25,000 per year and improve patient experience. Let’s keep up the good work.


Patient group

Support level

Haematology Tests

Biochemistry Tests


On Admission

All patients admitted to PICU, irrespective of level of support

FBC, clotting,
Cross match

U&E, Mg/Ca/ PO4 and LFT’s.

PCT if suspected infection

On admission if not done in the preceding 6 hours or if there are significant changes since

Red group:


Ventilation + 2 or more inotropes
Ventilation + Nitric oxide
CVVH + inotrope or ventilation
Neuroprotection with unstable ICP

FBC, clotting

U&E, Mg/ Ca/PO4

12 hourly



Once daily

Blue group:


High Support Level:
HFOV +/- 1 inotrope
Ventilation + 1 inotrope
CVVH if stable and no other organ failure
Neuroprotection with stable ICP
Patients who had surgery in the preceding 48 hours

FBC, clotting

U&E, Mg/ Ca/PO4

Once daily



On Consultant request

Yellow group:


Ventilation only
NIV +/- 1 inotrope
Self-ventilating / Vapotherm on 1 inotrope




Once daily for first 2 days.

Twice weekly once stable and on enteral feeds

Green group:


HDU level:
Stable on Vapotherm
Patients on no organ support
And tolerating more than 50% enteral feeds

These patients don’t need routine blood tests,EXCEPT for:

- patients who had surgery in the preceding 48 hours - Blue group

- patients tolerating less than 50% enteral feeds - check daily U/E

White group:

Long term stable patients:

Stable on PICU > 14 days on single organ support

These patients don’t need routine blood tests

Request tests as clinically indicated

Patient on PN

Minimum testing frequency. If patient needs more frequent testing based on support level please follow guidance for the appropriate group

See PN Monitoring guideline for patients on PN beyond 4 weeks


U&E, Mg, PO4, Ca

Once daily if abnormal. Twice weekly once stable



Twice weekly



Once weekly

Patients admitted following liver / kidney transplantation

Please follow liver / renal transplantation protocol for frequency of blood tests

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Record: 4030

To reduce variation of practice in requesting blood tests for patients admitted to PICU and decrease unnecessary tests being routinely ordered.

Clinical condition:
Target patient group: All children admitted to PICU
Target professional group(s): Secondary Care Doctors
Secondary Care Nurses
Adapted from:

Evidence base

Not supplied

Approved By

Trust Clinical Guidelines Group

Document history

LHP version 1.0

Related information

Not supplied

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