effects of BMI on ventilation and outcomeS in COVID–19 ARDS

René Schavemaker, Marcus J. Schultz, Wim K. Lagrand, Eline R. van Slobbe–Bijlsma,

Ary Serpa Neto, Frederique Paulus for the PRoVENT–COVID Collaborative group

Summary

Background

We describe the practice of ventilation and mortality rates in invasively ventilated normal-weight (18.5 ≤ BMI ≤ 24.9 kg/m²), overweight (25.0 ≤ BMI ≤ 29.9 kg/m²), and obese (BMI > 30 kg/m²) COVID-19 ARDS patients in a national, multicenter observational study, performed at 22 intensive care units in the Netherlands.

Methods

The primary outcome was a combination of ventilation variables and parameters over the first four calendar days of ventilation, including tidal volume, positive end–expiratory pressure (PEEP), respiratory system compliance, and driving pressure in normal–weight, overweight, and obese patients. Secondary outcomes included the use of adjunctive treatments for refractory hypoxaemia and mortality rates.

Results

Between 1 March 2020 and 1 June 2020, 1122 patients were included in the study: 244 (21.3%) normal-weight patients, 531 (47.3%) overweight patients, and 324 (28.8%) obese patients. Most patients received a tidal volume < 8 mL/kg PBW; only on the first day was the tidal volume higher in obese patients. PEEP and driving pressure were higher, and compliance of the respiratory system was lower in obese patients on all four days. Adjunctive therapies for refractory hypoxemia were used equally in the three BMI groups. Adjusted mortality rates were not different between BMI categories.

Conclusions

The findings of this study suggest that lung-protective ventilation with a lower tidal volume and prone positioning is similarly feasible in normal-weight, overweight, and obese patients with ARDS related to COVID-19. A patient’s BMI should not be used in decisions to forgo or proceed with invasive ventilation.

Full list of collaborators

(in alphabetic order) J.P. van Akkeren; A.G. Algera; C.K. Algoe; R.B. van Amstel; O.L. Baur; P. van de Berg; D.C.J.J. Bergmans; D.I. van den Bersselaar; F.A. Bertens; A.J.G.H. Bindels; M.M. de Boer; S. den Boer; L.S. Boers; M. Bogerd; L.D.J. Bos; M. Botta; J.S. Breel; H. de Bruin; S. de Bruin; C.L. Bruna; L.A. Buiteman–Kruizinga; O. Cremer; R.M. Determann; W. Dieperink; D.A. Dongelmans; H.S. Franke; M.S. Galek Aldridge; M.J. de Graaff; L.A. Hagens; J.J. Haringman; N.F.L. Heijnen; S.Hiel; S.T. van der Heide; P.L.J. van der Heiden; L.L. Hoeijmakers; L. Hol; M. W. Hollmann; M.E. Hoogendoorn; J. Horn; R. van der Horst; E.L.K. Ie; D. Ivanov; N.P. Juffermans; E. Kho; E.S. de Klerk; A.W.M. Koopman; M. Koopmans; S. Kucukcelebi; M.A. Kuiper; D.W. de Lange; N. van Mourik; S.G. Nijbroek; M. Onrust; E.A.N. Oostdijk; F. Paulus; C.J. Pennartz; J. Pillay; L. Pisani; I.M. Purmer; T.C.D. Rettig; J.P Roozeman; M.T.U. Schuijt; M.J. Schultz; A. Serpa Neto; M.E. Sleeswijk; M.R. Smit; P.E. Spronk; W. Stilma; A.C. Strang; A. M. Tsonas; P.R Tuinman; C.M.A. Valk; F.L. Veen; A.P.J. Vlaar; L.I. Veldhuis; P. van Velzen; W.H. van der Ven; P. van Vliet; P. van der Voort; H.H. van der Wier; L. van Welie; H.J.F.T. Wesselink; B. van Wijk; T. Winters; W.Y. Wong; A.R.H. van Zanten.