Telephoning of Critical Results

In the hospital, all results will be telephoned 24 hours a day if they meet the criteria stated below. All GP results meeting the telephone criteria will be telephoned during the normal working day.  Please refer to the discipline-specific sections for detailed information.

Haematology

In-patients:

All Haematology results meeting the criteria in the table below will be phoned to the requesting clinician, except where the results are persistently abnormal. In these cases, only a change to results that may affect patient management will be phoned.

Analyte Critical Limit(s)
Hb <70g/l  or >200g/l
Platelet count <50 x 109/l or >1000 x 109/l
Suspected leukaemia Blasts,high WBC,etc.
Neutrophils <1.0 x 109/l  or >30 x 109/l
Glandular fever screen Positive
Malaria screen Positive
Emergency Sickle Screen Positive or negative
INR >5.0
APTT Ratio >4.5
Fibrinogen <1.5g/l or >11g/l
DDimer >20.0ug/ml

GP Results:

Results phoned to the out-of-hours service should also be phoned to the GP surgery the following morning to verify that action has been taken. All Haematology results meeting the criteria in the table below will be phoned to the requesting clinician, or the out-of-hours service, except where the results are persistently abnormal. In these cases, only a change to results that may affect patient management will be phoned.

In all cases, if there is concern that the patient’s condition may result in the patient being contacted by an on-call clinician, this should be made clear to the patient during their appointment.

Analyte Critical Limit(s)
Hb <80g/l  or >200g/l
Platelet count <50 x 109/l or >1000 x 109/l
Suspected leukaemia Blasts,high WBC,etc.
Neutrophils <1.0 x 109/l  or >30 x 109/l
Malaria screen Positive
Emergency Sickle Screen Positive or negative
INR >5.0
APTT Ratio >4.5
Fibrinogen <1.5g/l or >11g/l
DDimer Any result >=0.5ug/ml

Additional considerations

In addition to contacting the requesting clinician, the following cases will be promptly referred to a Consultant Haematologist for direct clinical liaison and advice:

• Newly presented leukaemias
• Newly presented malaria infection
• Positive sickle haemoglobin screen in patients about to undergo anaesthesia
• Any low factor assay result for patients undergoing an emergency procedure.
• Persistently prolonged isolated APTT or PT result where there is an acute bleeding risk to the patient (when the patient is not on anticoagulant therapy).

Chemical Pathology

In-patients:

In the hospital, all results in the below table will be telephoned 24 hours a day if they meet the criteria stated in the table below.

GP Results:

The below table identifies the arrangements for telephoning GP results out-of-hours, indicating whether the results are telephoned to the GP out-of-hours service, or whether they are telephoned to the GP practice the following working day.

Therapeutic drug monitoring results will be telephoned (as specified below) if they are significantly outside the therapeutic range.  It must be stressed, however, that the patient and not the biochemistry result should be treated as therapeutic ranges are only guides and there is wide inter-individual variation.

ANALYTELOWER LIMIT (and below)HIGHER LIMIT (and above)GP Telephoning Out of HoursSource
Sodium  (mmol/L)120
<130 if <16yrs
150GP Out of Hours ServiceRCPath 2017
RCPath 2017 for children as particular concern of risk of death in children with hypoNa
Potassium  (mmol/L)2.56.5GP Out of Hours ServiceRCPath 2017
Potassium  (mmol/L)
Heart Failure Nurses**
3.95.4GP Out of Hours ServiceBarnsley and Rotherham local agreement
Potassium  (mmol/L)
GP Patients†
6.0
When AKI >1
GP Out of Hours ServiceRCPath 2017
On new occurrences
Glucose  (mmol/L)2.525
(>15 if <16 years)
GP Out of Hours ServiceRCPath 2017
State 30mmol/L for GP known DM patients
Glucose results < 2.5 may be less crucial to phone immediately
Urea  (mmol/L)30
(>10 if <16 years)
GP Out of Hours ServiceRCPath 2017
Creatinine  (umol/L)350
(>200 if <16 years)
GP Out of Hours ServiceRCPath 2017 (actually states 354 umol/L)  higher thresholds for known CKD or pt on dialysis.
Need specific local points for babies.
AKILevel of 2 or aboveGP Out of Hours ServiceAll new occurrences
AKI†
GP Patients
1
When Potassium >6.0
GP Out of Hours ServiceRCPath 2017
All new occurrences
Serum Bicarbonate10Next Working DayRCPath 2017
GP only
Calcium - Adj  (mmol/L)1.83GP Out of Hours ServiceBarnsley and Rotherham local agreement
PO4  (mmol/L)0.3GP Out of Hours ServiceRCPath 2017
Urgent inpatient, GP urgent, if OOH within 24 hours
Mg  (mmol/L)0.4GP Out of Hours ServiceRCPath 2017
CK  (U/L)5000 unless ?MIGP Out of Hours ServiceRCPath 2017
ALT (U/L)735GP Out of Hours ServiceRCPath 2017
AST (U/L)510GP Out of Hours ServiceRCPath 2017
Amylase  (U/L)590GP Out of Hours ServiceRCPath 2017
Lipase (U/L)265GP Out of Hours ServiceBarnsley and Rotherham local agreement
Bilirubin  (umol/L)300Next Working DayBarnsley and Rotherham local agreement
Conjugated Bilirubin  (umol/L)25Next Working DayNeonates only
RCPath 2017
Triglyceride  (mmol/L)20Next Working DayRCPath 2010
Ammonia  (umol/L)AllNext Working DayBarnsley and Rotherham local agreement
Bile Acids  (umol/L)14Next Working DayBarnsley and Rotherham local agreement
Iron  (umol/L)55Next Working DayBarnsley and Rotherham local agreement
Uric Acid/Urate (umol/L)340Next Working DayAnte-natal only RCPath 2017
CRP  (mg/L)300GP Out of Hours ServiceRCPath 2017
Troponin I High Sensitivity (ng/L)120GP Out of Hours ServiceRCPath 2017, Local agreement
GP Troponin I High Sensitivity (ng/L)>3
advise to call duty Biochemist for advice
GP Out of Hours ServiceBarnsley and Rotherham local agreement
Cortisol (nmol/L)50 unless part of O/N Dexamethasone suppression testNext Working DayRCPath 2017
Cortisol (nmol/L) (SST 30 minutes)250Next Working DayRCPath 2017 – To be phoned by Biochemistry Consultant authorising the DFT
fT4  (pmol/L)530Next Working DayBarnsley and Rotherham local agreement
In patient within 2 hours
GP/ Out pt next working day
fT310 if FT4 normal with suppressed TSHNext Working DayBarnsley and Rotherham local agreement
In patient within 2 hours
GP/ Out pt next working day
TSH  (mIU/L)50 for 1st timeNext Working DayBarnsley and Rotherham local agreement
In patient within 2 hours
GP/ Out pt next working day
Paracetamol  (mg/L)If detectedGP Out of Hours ServiceBarnsley and Rotherham local agreement
Salicylate  (mg/L)If detectedGP Out of Hours ServiceBarnsley and Rotherham local agreement
Phenytoin  (mg/L)25Next Working DayRCPath 2017
Carbamazepine  (mg/L)25Next Working DayRCPath 2010
Theophylline  (mg/L) 25Next Working DayRCPath 2017
Digoxin  (ug/L)2.5GP Out of Hours ServiceRCPath 2017
Lithium  (mmol/L)1.5GP Out of Hours ServiceRCPath 2017
Phenobarbitone  (mg/L)70Next Working DayRCPath 2010
Valproate  (mg/L)150 for 1st timeNext Working DayBarnsley and Rotherham local agreement
PBGPositiveNext Working DayBarnsley and Rotherham local agreement
Ethanol (mg/L)DetectedNext Working DayBarnsley and Rotherham local agreement
Osmolality (mosm/kg)270300Next Working DayBarnsley and Rotherham local agreement
Hba1c (mmol/mol)120GP Out of Hours ServiceSY&B local Agreement for first-time HbA1c results without a glucose requested / not known diabetic
Blood GasAllNext Working DayBarnsley and Rotherham local agreement

**Rotherham Heart failure patients that have been identified with a sticker on the request card are phoned at different potassium limits.