*! version 1.2 18 Aug 2024

Title

pelod2 -- a command to calculate the Pediatric Logistic Organ Dysfunction 2 (PELOD-2) score

Syntax

pelod2 newvar
[if] [in]
,
map(varname) lactate(varname) pupils(varname)
gcs(varname) mv(varname) pco2(varname) wbc(varname)
creatinine(varname) plt(varname)
[fio2(varname) pao2(varname) pfratio(varname)]
[age(varname) dob(varname) doa(varname)]
[options]

Cardiovascular
map(varname) mean arterial pressure

lactate(varname) lactate level (default: mg/dL)

Neurologic
pupils(varname) pupil reaction (0=reactive, 1=fixed)

gcs(varname) Glasgow Coma Scale score

Respiratory
mv(varname) mechanical ventilation status (0=no, 1=yes)

pco2(varname) PaCO2 level (mmHg)

fio2(varname) fraction of inspired oxygen (FiO2) (0.21 - 1.0)

pao2(varname) partial pressure of oxygen (PaO2) (mmHg)

----- or -----
pfratio(varname) PaO2/FiO2 ratio

Renal
creatinine(varname) creatinine level (default: mg/dL)

Hematologic
wbc(varname) white blood cell count (default: cells/mm3)

plt(varname) platelet count (default: cells/mm3)

Age
age(varname) age category (0-5)

----- or -----
dob(varname) date of birth

doa(varname) date of admission

Additional Options
rawscore(newvar) specify variable name for the raw PELOD-2 score

si use SI units for lactate and creatinine

pltunit(#) specify platelet count unit (default: 1)

wbcunit(#) specify white blood cell count unit (default: 1)

Debugging Options
noimputation treat missing values as missing

novalidation skip out-of-range data checks

trace turn on trace for debugging

Description

pelod2 calculates the Pediatric Logistic Organ Dysfunction 2 (PELOD-2) score. The scores is an outcome prognostication tools that has been used
extensively in clinical care and research to calculate the expected mortality and control for illness severity in pediatric intensive care units.

See Citation for proper attribution.

Options

For all required variables, if there is data missing you will receive a warning. The calculation will still be performed using normal values for the age group.

Cardiovascular

map(varname) specifies the name of the mean arterial pressure variable in mmHg.

lactate(varname) specifies the name of the lactate level variable. Default unit is mg/dL; use the si option for mmol/L.

Neurologic

pupils(varname) specifies the name of the pupillary reaction to light. The variables must be coded as: 0 = reactive | 1 = both fixed

gcs(varname) specifies the name of the Glasgow Coma Scale score variable.

Respiratory

mv(varname) specifies the name of the mechanical ventilation status variable. The variable must be coded as 0 = No | 1 = Yes.

pco2(varname) specifies the name of the PaCO2 level variable in mmHg.

You can specify either the PaO2/FiO2 ratio directly, or the PaO2 and FiO2 variables
separately and the ratio will be calculated.

fio2(varname) specifies the name of the fraction of inspired oxygen (FiO2) variable. It can be entered as 0.21-1.0 or 21-100.

pao2(varname) specifies the name of the partial pressure of oxygen (PaO2) variable in mmHg.

pfratio(varname) specifies the name of the PaO2/FiO2 ratio variable.

Hematologic

wbc(varname) WBC variable in cells/mm3.

plt(varname) Platelet Count variable in cells/mm3.

Renal

creatinine(varname) specifies the name of the creatinine level variable. Default unit is mg/dL; use the si option for μmol/L.

Age

Age can be specified as either a categorical variable (0-5) or as date of birth
and admission date.

age(varname) specifies the name of the age category variable (0-5). See the remarks

dob(varname) specifies the name of the date of birth variable (in Stata date format).

doa(varname) specifies the name of the date of admission variable (in Stata date format).

Options

rawscore(varname) specifies the name of a variable to hold the raw PELOD-2 score.

noimputation calculated score will be set to missing if any of the included variables are missing. The default is to use normal physiological values for age when values are missing.

novalidation specifies that out-of-range data checks should be skipped.
The default is to treat out-of-range values as missing.

wbcunit(numeric) If not specified, it defaults to cells/mm3 - wbcunit(1). If data is in 1000 * cells/mm3 specify wbcunit(1000).

pltunit(numeric) If not specified, it defaults to cells/mm3 - pltunit(1). If data is in 1000 * cells/mm3 specify pltunit(1000).

si specifies that lactate and creatinine values are provided in SI units (mmol/L for lactate, μmol/L for creatinine). Otherwise, conventional units (mg/dL) are used.

trace turns on trace for debugging purposes.

Remarks

Age can be specified either as a categorical variable (0-5) or by providing the date of birth and date of admission. If both are provided, the command will use the categorical age variable. The age categories are defined as follows:

0: 0-30 days

1: 31-365 days

2: 366-730 days

3: 731-1825 days

4: 1826-4380 days

5: >4380 days

For the respiratory dysfunction, you can provide either the PaO2/FiO2 ratio directly or the PaO2 and FiO2 separately. If both are provided, the command will use the directly provided ratio.

By default, the command performs data validation and imputes missing values with normal physiological values for age. These behaviors can be modified using the novalidation and noimputation options.

References

[1] Leteurtre S, Duhamel A, Salleron J, Grandbastien B, Lacroix J, Leclerc F. PELOD-2. Crit Care Med. 2013;41(7):1761–73.

Citation

Please cite this command as:

Azamfirei R, Mennie C, Fackler J, Kudchadkar SR. Pediatric Critical Care Illness Severity Toolkit: Stata Commands for Calculation of Pediatric Index of Mortality and Pediatric Logistic Organ Dysfunction Scores. JCCM. 2024;10(1):16-18. | DOI: 10.2478/jccm-2023-0033

Authors

Razvan Azamfirei | Email: stata@azamfirei.com

Colleen Mennie

James Fackler

Sapna R. Kudchadkar

License

Copyright 2023 Razvan Azamfirei

Licensed under the Apache License, Version 2.0 (the"License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at:

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the License for the specific language governing permissions and limitations under the License.

Also see

pim3, prismscore, pccmtoolkit