The Dutch Data Warehouse, a multicenter and full-admission electronic health records database for critically ill COVID-19 patients

Fleuren, Lucas M.; Dam, Tariq A.; Tonutti, Michele; de Bruin, Daan P.; Lalisang, Robbert C. A.; Gommers, Diederik; Cremer, Olaf L.; Bosman, Rob J.; Rigter, Sander; Wils, Evert-Jan; Frenzel, Tim; Dongelmans, Dave A.; de Jong, Remko; Peters, Marco; Kamps, Marlijn J. A.; Ramnarain, Dharmanand; Nowitzky, Ralph; Nooteboom, Fleur G. C. A.; de Ruijter, Wouter; Urlings-Strop, Louise C.; Smit, Ellen G. M.; Mehagnoul-Schipper, D. Jannet; Dormans, Tom; de Jager, Cornelis P. C.; Hendriks, Stefaan H. A.; Achterberg, Sefanja; Oostdijk, Evelien; Reidinga, Auke C.; Festen-Spanjer, Barbara; Brunnekreef, Gert B.; Cornet, Alexander D.; van den Tempel, Walter; Boelens, Age D.; Koetsier, Peter; Lens, Judith; Faber, Harald J.; Karakus, A.; Entjes, Robert; de Jong, Paul; Rettig, Thijs C. D.; Arbous, Sesmu; Vonk, Sebastiaan J. J.; Fornasa, Mattia; Machado, Tomas; Houwert, Taco; Hovenkamp, Hidde; Noorduijn-Londono, Roberto; Quintarelli, Davide; Scholtemeijer, Martijn G.; de Beer, Aletta A.; Cina, Giovanni; Beudel, Martijn; Herter, Willem E.; Girbes, Armand R. J.; Hoogendoorn, Mark; Thoral, Patrick J.; Elbers, Paul W. G.

doi:10.1186/s13054-021-03733-z

Critical Care

Table 2 Derived parameters in the Dutch Data Warehouse

From: The Dutch Data Warehouse, a multicenter and full-admission electronic health records database for critically ill COVID-19 patients

Parameter	Calculation	Tolerance	Comments
Basophils percentage	Basophils divided by leukocytes	1 h
Body mass index	Height divided by weight squared	/	A measurement is added for each measurement of weight, using the latest available height for the patient
Driving pressure	Plateau pressure minus peep	8 h/1 h
Driving pressure	Tidal volume divided by lung compliance static	1 h
Eosinophils percentage	Eosinophils divided by leukocytes	1 h
Glasgow coma scale total	Glasgow coma scale eye plus Glasgow coma scale motor plus Glasgow coma scale verbal	1 h
Inspiratory expiratory ratio	Inspiratory time divided by expiratory time	1 h
Lung compliance dynamic	Tidal volume divided by (peak pressure minus peep)	1 h
Lung compliance static	Tidal volume divided by (plateau pressure minus peep)	1 h/8 h/1 h
Lung compliance static	Tidal volume divided by pressure above peep	1 h
Lymphocytes percentage	Lymphocytes divided by leukocytes	1 h
Mechanical power per kg	Mechanical power divided by ideal body weight	/	Ideal body weight is calculated from the patient's gender and height
Mechanical power	(0.098 × respiratory rate measured ventilator times tidal volume times (peak pressure minus (driving pressure × 0.5)) × 0.001	1 h
Mechanical power	(0.098 × respiratory rate measured ventilator times tidal volume times (peak pressure plus peep) × 0.001	1 h
Minute volume derived	(tidal volume times respiratory rate measured) × 0.001	1 h
Monocytes percentage	Monocytes divided by leukocytes	1 h
Neutrophils percentage	Neutrophils divided by leukocytes	1 h
Pao2 over fio2	po2 arterial divided by fio2	8 h/1 h	Measurements of ‘fio2’ within 8 h before ‘po2’ are given priority over those measured within 1 h afterwards
Pco2 minus end tidal co2	pco2 arterial minus end tidal co2	8 h	Measurements of ‘end tidal co2’ within 1 h before `pco2` are given priority over those measured afterwards
Physiological dead space	pco2 minus end tidal co2 minus pco2 arterial	8 h	Measurements of ‘pco2 arterial’ within 8 h before ‘pco2 minus end tidal co2’ are given priority over those measured within 8 h afterwards
Plateau pressure	Driving pressure minus peep	8 h/1 h
Po2 unspecified over fio2	po2 unspecified divided by fio2	8 h/1 h	Measurements of ‘fio2’ within 8 h before ‘po2’ are given priority over those measured within 1 h afterwards
Rapid shallow breathing index	(Respiratory rate set divided by tidal volume) × 1000	1 h
Respiratory rate difference	Respiratory rate measured ventilator minus respiratory rate set	1 h
Tidal volume per kg	Tidal volume divided by ideal body weight	/	Ideal body weight is calculated from the patient's gender and height
Ureum over creatinine	Ureum minus creatinine	1 h
Ventilatory ratio	(minute volume times pco2 arterial) divided by (ideal body weight × 100 × 37.5)	1 h	Ideal body weight is calculated from the patient's gender and height

Overview of all derived parameters and their calculation in the data warehouse. The tolerance gives the hours that two measurements may be apart. In case multiple observations are found in that time window, the slash indicates the hierarchy. i.e., 1 h/8 h/1 h means observations are included 1 h before, otherwise 8 h before, or lastly 1 h after the other measurement

Back to article page

ISSN: 1364-8535

Contact us

Submission enquiries: journalsubmissions@springernature.com