Who Cares to Know: Defining Neonatal Critical Laboratory Values

Theodora Stavroudis, MDJohns Hopkins University

tstavro1@jhmi.edu

October 28, 2007

American Academy of Pediatrics

Council on Clinical Information Technology

I have no relevant financial relationships with the manufacturer(s) of any commercial product(s) and/or provider(s) of commercial services discussed in this CME activity.

Background

• Medical errors are common in the NICU– NICU patients are eight more times likely to experience a

medication error with the potential to cause harm than adults (Kaushal et al 2001)

– Ten percent of medical errors result from either error or delay in diagnosis, delay in treatment, or in responding to an abnormal test (Suresh et al 2004)

• In adults, information technology solutions have been shown to help prevent these errors

Alerting Systems & Algorithms

• Clinical information systems can generate alert messages using a variety of media– Phone calls, computer terminal messages, e-mails,

flashing lights, alpha-numeric pages, SMS messages

• Problems: – Resource-intensive

– Signal-to-Noise Ratio

Signal-to-Noise Ratio

• White Blood Cell Count 35,000– Do you care to be paged?

• Yesterday’s WBC was 37,000– Do you still care?

Signal-to-Noise Ratio

• Total Bilirubin 10 mg/dl– Do you care to be paged?

• Patient is a five day old term infant– Do you still care?

Aims & Hypothesis

Aims

1) To define what constitutes critical laboratory values (CLV) in the NICU.

MUST KNOW vs. MUST KNOW NOW

2) To determine if definitions of CLV vary among health care providers in the NICU.

Hypothesis

Definitions of CLV do not vary among health care providers in the NICU.

Methods

Study Type

• Survey at a tertiary medical center conducted in 2006

CLV Evaluated:

• WBC, ANC, CRP, hematocrit, platelets, sodium, potassium, bicarbonate, calcium, creatinine, triglycerides

Population Studied

• Senior residents, fellows and attendings in the NICU

Analysis

• Descriptive statistics, chi-square

Sample Survey Question

The current hematocrit is 65. In the last 24 hours, there has not been a hematocrit level ≥ 65.

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

What hematocrit do you prefer to be paged about?

Lab Value Scenario Is this important information to know?

Circle only one number

Would you like to be paged with this lab

value?Circle only one number

Yes Uncertain No Yes Uncertain

No

Results

Provider Surveyed Responded

  n n %

Attendings 15 10 67

Fellows 6 6 100

Residents 54 31 57

Results - Attendings

Critical Laboratory Value

Platelets < 50 1.5 2.3

Absolute Neutrophil Count < 501 1.8 2.6

Potassium >7 2.5 3.3

Hematocrit < 23 2.3 3.6

Bands >20% 2.3 4.6

White Blood Cell Count < 5,000 2.6 4.6

Bicarbonate < 15 2.8 4.6

Triglycerides > 200 3.0 4.8

Ionized Calcium 0.8 3.0 4.9

Hematocrit > 65 3.3 4.9

Sodium < 129 2.8 5.1

Creatinine > 1.5 2.9 5.3

White Blood Cell Count > 30,000 3.1 5.5

Sodium > 145 2.9 5.6C-reactive Protein > 4 3.6 4.9

Important to KnowAverage

Important to PageAverage

Results - Fellows

Critical Laboratory Value

Bicarbonate < 15 1.2 1.2

Hematocrit > 65 1.5 1.3

Absolute Neutrophil Count < 501 1.5 2

Sodium > 145 2 2

White Blood Cell Count < 5,000 1.8 2.3

Triglycerides > 200 2 2.3

Sodium < 129 2.2 2.8

Potassium >7 2.3 3

C-reactive Protein > 4 2 3.3

Platelets < 50 2.2 3.3

White Blood Cell Count > 30,000 3 3.3

Creatinine > 1.5 3.2 3.3

Ionized Calcium 0.8 2.5 3.8

Hematocrit < 23 3 4.5

Bands >20% 2.8 4.6

Important to KnowAverage

Important to PageAverage

Results - ResidentsCritical Laboratory Value

White Blood Cell Count < 5,000 2.4 2.4

Bicarbonate < 15 1.8 2.6

Absolute Neutrophil Count < 501 2 2.8

Bands >20% 2.1 2.8

Hematocrit > 65 2.3 3.2

Triglycerides > 200 2.6 3.3

White Blood Cell Count > 30,000 2.6 3.5

C-reactive Protein > 4 2.7 3.6

Platelets < 50 2.6 3.7

Sodium > 145 2.8 3.8

Potassium >7 3.5 4.1

Sodium < 129 3.2 4.3

Hematocrit < 23 3.6 5.3

Ionized Calcium 0.8 3.6 5.3

Creatinine > 1.5 3.9 6.6

Important to KnowAverage

Important to PageAverage

CLV Residents Fellows Attendings P-value

ITK Page ITK Page ITK Page ITK Page

ANC<501 86 64 83 50 88 88 0.98 0.30

Bands>20% 93 78 100 83 88 50 0.66 0.25

Bicarb<15 69 43 83 50 75 43 0.76 0.95

CRP>4 59 36 67 50 75 29 0.68 0.72

Cr>1.5 93 79 67 40 75 38 0.14 0.04

iCa<0.8 93 89 100 100 63 38 0.04 0.002

K>7 97 86 100 100 88 50 0.47 0.03

Hct<23 83 68 83 67 100 50 0.45 0.64

Hct>65 86 56 100 83 75 38 0.42 0.23

Plt<50 90 71 100 100 100 88 0.46 0.24

Na<129 55 21 83 67 88 13 0.14 0.05

Na>145 72 46 100 83 100 13 0.09 0.03

Trig>200 50 19 50 50 75 38 0.44 0.21

WBC>30,000 86 64 67 50 75 38 0.47 0.37

WBC<5,000 76 57 83 83 88 50 0.75 0.41

Conclusions

• Significant differences exist by role on what CLV should be paged to health care providers.

• Differences are not related to perceived importance of the data.

• Future studies are needed to determine the reasons behind the differences in desires to be paged by health care providers.

Future Directions• Conduct a national survey of providers to promote national

adoption of CLV among neonates• Create further algorithms for CLV and links to other

clinical decision support systems– Culture results– Blood gas results– Oxygen requirements– Fluid status (cc/kg/day, urine output)– Drug levels– Central line placement duration– Medication alerts

• Implement alpha-numeric pagers using CLV discovered in this study– Measure physician response time to therapy for CLV– Measure prevention of adverse consequences from this

intervention

Study is Underway!

Acknowledgements

• Collaborators:

– Anusha Hemachandra Streubel, MD, MPH

– Christoph U. Lehmann, MD

• Johns Hopkins senior residents, NICU fellows, and NICU attendings

• Johns Hopkins Quality and Safety Research Group

CLV All Residents Fellows Attendings P-value

ITK Page ITK Page ITK Page ITK Page ITK Page

ANC<501 86 67 86 64 83 50 88 88 0.98 0.30

Bands>20% 93 73 93 78 100 83 88 50 0.66 0.25

Bicarb<15 72 44 69 43 83 50 75 43 0.76 0.95

CRP>4 63 37 59 36 67 50 75 29 0.68 0.72

Cr>1.5 86 66 93 79 67 40 75 38 0.14 0.04

iCa<0.8 88 81 93 89 100 100 63 38 0.04 0.002

K>7 95 81 97 86 100 100 88 50 0.47 0.03

Hct<23 86 64 83 68 83 67 100 50 0.45 0.64

Hct>65 86 56 86 56 100 83 75 38 0.42 0.23

Plt<50 93 79 90 71 100 100 100 88 0.46 0.24

Na<129 65 26 55 21 83 67 88 13 0.14 0.05

Na>145 81 45 72 46 100 83 100 13 0.09 0.03

Trig>200 55 27 50 19 50 50 75 38 0.44 0.21

WBC>30,000 81 57 86 64 67 50 75 38 0.47 0.37

WBC<5,000 79 60 76 57 83 83 88 50 0.75 0.41