Beth Israel Deaconess Medical Center Laboratory Manual

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Critical Values are laboratory results which indicate a condition likely to require prompt clinical intervention.  It is the responsibility of the laboratory to communicate these results immediately to a health care provider.

Note:  Additional results, although not critical, may be considered significant or unusual and will be communicated to the patient’s provider at the discretion of the Laboratory Director. Click here to view the critical value policy.

This list was approved by the MEC (Core Clinical Services Committee) on 1/27/2009.

Go directly to: Chemistry , Blood Bank , Hematology , Microbiology

Test Name	Critical Value		Frequency (If not each time)
Acetaminophen		High: > 50 µg/mL
Bicarbonate	Low: < 15 mmol/L	High: > 40 mmol/L
Bilirubin (in neonate)		High: > 16 mg/dL
Calcium, free	Low: < 1.00 mmol/L	High: > 1.45 mmol/L
Calcium, total (serum)	Low: < 6.0 mg/dL	High: > 13.0 mg/dL
Carbamazepine (Tegretol)		High: > 13.5 µg/mL
Carboxyhemoglobin		High: > 15 %
Chloride	Low: < 80 mmol/L	High: >120 mmol/L
Digoxin		High: > 2.5 ng/mL
Gentamicin		High: > 12.0 µg/mL
Glucose	Low: < 50 mg/dL	High: > 450 mg/dL
Lactate		High: > 4.0 mmol/L	No repeat calls for critical values within same day
Lithium		High: > 2.0 mmol/L
Magnesium (serum)	Low: < 1.0 mg/dL	High: > 4.5 mg/dL
Methemoglobin		High: >5%
Osmolality	Low: < 250 Osm/kg	High: > 326 Osm/kg
pCO 2 (arterial)	Low: < 20 mm Hg	High: > 60 mm Hg	New Value No repeat calls for critical values within same day.
pH (arterial)	Low: < 7.26	High: > 7.55	New Value No repeat calls for critical values within same day.
pO 2 (arterial)	Low: < 60 mm Hg	High: > 600 mm Hg	New Value No repeat calls for critical values within same day.
Phenobarbital		High: > 60 µg/mL
Phenytoin (Dilantin)		High: > 25 µg/mL
Phosphate (serum)	Low: < 1.0 mg/dL
Potassium (serum)	Low: < 3.0 mmol/L	High: > 5.9 mmol/L
Procainamide (Pronestyl)		High: > 12 µg/mL
Quinidine		High: > 10 µg/mL
Salicylate		High: > 30 mg/dL
Sodium	Low: < 125 mmol/L	High: > 150 mmol/L
Theophylline		High: > 22 µg/mL
Tobramycin		High: > 12 µg/mL
Troponin T		High: >0.10 ng/mL	New Value No repeat calls for critical values within same day.
Valproic acid (Depakene)		High: > 125 µg/mL
Vancomycin		High: > 45 µg/mL

Test Name	Critical Value	Frequency (If not each time)
Antibody screen / crossmatch	Positive antibody screen or incompatible crossmatch following emergency release of blood or urgent request for crossmatched blood.
Direct anti-globulin test (in neonate)	Positive
Heparin antibody test	Positive
Antibody screens	Positive (Labor and Delivery only)	First time positive

Test Name	Critical Value		Frequency (If not each time)
Leukemic cells	Presence of any leukemic cells in blood or body fluid		Hematology physician will call new results after smear review.  No repeat calls for critical values within 3 months unless prior result was normal and new result is critical.
CSF cell count		High: WBC’s > 20/µL
Fibrinogen	Low: < 100 mg/dL For OB patients between the ages 14 and 52: < 200 mg/dL
Hematocrit	Low: < 15 % (inpatients)          <25 % (outpatients)	High: >60 % (outpatients)	New Value No repeat calls for critical values within 3 months unless prior result was normal and new result is critical. (no calls to Hem/Onc)
Malaria smear	Positive		Initial Detection
Platelet count	Low: < 10K/µL (inpatients) <50K/µL (outpatients) <50K/µL (NICU patients)	High: >999 K/µL	New Value No repeat calls for critical values within 3 monthsunless prior result was normal and new result is critical. (no calls to 11R, 7F, Hem/Onc)
INR		>=5.0 (corresponds to a PT of 44.6. seconds)
Partial thromboplastin time		>50 secs   (outpatients) >100 secs (inpatients)
White blood cell count	Low: < 5.0 K/µL (neonate) < 2.0 K/µL (outpatients)	High: >30.0 K/µL (outpatients)	New Value   No repeat calls for critical values within 3 months unless prior result was normal and new result is critical.  (no calls to Hem/Onc)

Test Name	Critical Value	Frequency (If not each time)
Acid fast smear	Positive	Initial Detection No repeat calls for critical values within two weeks.
Bacterial antigens (CSF)	Positive
Blood culture	Positive	Initial Detection of organism by Gram stain No repeat calls for critical values within one week.
C. difficile toxin	Positive	Initial Detection No repeat calls for critical values within one week.
Cerebrospinal fluid	Positive Gram stain, fungal stain or culture
CMV Antigenemia	Positive	Initial Detection No repeat calls for critical values within one month.
CMV Viral Load	Positive	Initial Detection No repeat calls for critical values within one month
Cryptococcal antigen (CSF or Blood)	Positive	Initial Detection No repeat calls unless significant increase (4 fold)
Malarial antigen	Positive
Mycobacterium tuberculosis	First positive and Multi-drug resistant	Initial Detection No repeat calls for critical values within two weeks.
Other Mycobacterium species	First positive	Initial detection; each source
Respiratory Viral Antigen Screen, DFA	Positive Called on inpatients ONLY
Tissue and Sterile fluids as specified	Gram Stains: Positive gram stains:      Tissues except foot      Sterile fluids:  joint, pericardial, peritoneal, pleural &          vitreous fluids will be called Cultures: Corresponding positive cultures will be called only if gram stain negative	Initial Detection of organism by Gram stain and/or culture. No repeat calls for critical values within one week.

Additional results, although not critical, may be considered significant or unusual and will be communicated to the patient's provider at the discretion of the Laboratory Director.

Reviewed/Revised  10/28/2009