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Original article

Vol. 152 No. 2526 (2022)

Critical care staffing ratio and outcome of COVID-19 patients requiring intensive care unit admission during the first pandemic wave: a retrospective analysis across Switzerland from the RISC-19-ICU observational cohort

  • Marie-Madlen Jeitziner
  • André Moser
  • Pedro D Wendel-Garcia
  • Matthias Thomas Exl
  • Stefanie Keiser
  • Reto A. Schuepbach
  • Urs Pietsch
  • Sara Cereghetti
  • Filippo Boroli
  • Julien Marrel
  • Anne-Aylin Sigg
  • Hatem Ksouri
  • Peter Schott
  • Alexander Dullenkopf
  • Isabelle Fleisch
  • Antje Heise
  • Jean-Christophe Laurent
  • Stephan M. Jakob
  • Matthias P. Hilty 
  • Yok-Ai Que
DOI
https://doi.org/10.4414/SMW.2022.w30183
Cite this as:
Swiss Med Wkly. 2022;152:w30183
Published
20.06.2022

Summary

STUDY AIM: The surge of admissions due to severe COVID-19 increased the patients-to-critical care staffing ratio within the ICUs. We investigated whether the daily level of staffing was associated with an increased risk of ICU mortality (primary endpoint), length of stay (LOS), mechanical ventilation and the evolution of disease (secondary endpoints).

METHODS: We employed a retrospective multicentre analysis of the international Risk Stratification in COVID-19 patients in the ICU (RISC-19-ICU) registry, limited to the period between March 1 and May 31, 2020, and to Switzerland. Hierarchical regression models were used to investigate crude and adjusted effects of the critical care staffing ratio on study endpoints. We adjusted for disease severity and weekly caseload.

RESULTS: Among the 38 participating Swiss ICUs, 17 recorded staffing information. The study population included 437 patients and 2,342 daily assessments of patient-to-critical care staffing ratio. Median of daily patient-to-nurse ratio started at 1.0 [IQR 0.5–1.5; calendar week 9] and peaked at 2.4 (IQR 0.4–2.0; calendar week 16), while the median of daily patient-to-physician ratio started at 4.0 (IQR 2.1–5.0; calendar week 9) and peaked at 6.8 (IQR 6.3–7.3; calendar week 19). Neither the patient-to-nurse (adjusted OR 1.28, 95% CI 0.85–1.93; doubling of ratio) nor the patient-to-physician ratio (adjusted OR 1.07, 95% CI 0.87–1.32; doubling of ratio) were associated with ICU mortality. We found no association of daily critical care staffing on the secondary endpoints in adjusted models.

CONCLUSION: We found no association of reduced availability of critical care staffing resources in Swiss ICUs with overall ICU length of stay nor mortality. Whether long-term outcome of critically ill patients with COVID-19 have been affected remains to be studied.

References

  1. Wendel Garcia PD, Fumeaux T, Guerci P, Heuberger DM, Montomoli J, Roche-Campo F, et al.; RISC-19-ICU Investigators. Prognostic factors associated with mortality risk and disease progression in 639 critically ill patients with COVID-19 in Europe: initial report of the international RISC-19-ICU prospective observational cohort. EClinicalMedicine. 2020 Aug;25:100449. https://doi.org/10.1016/j.eclinm.2020.100449
  2. Kleinpell R, Ferraro DM, Maves RC, Kane Gill SL, Branson R, Greenberg S, et al. Coronavirus Disease 2019 Pandemic Measures: Reports From a National Survey of 9,120 ICU Clinicians. Crit Care Med. 2020 Oct;48(10):e846–55. https://doi.org/10.1097/CCM.0000000000004521
  3. Wahlster S, Sharma M, Lewis AK, Patel PV, Hartog CS, Jannotta G, et al. The Coronavirus Disease 2019 Pandemic’s Effect on Critical Care Resources and Health-Care Providers: A Global Survey. Chest. 2021 Feb;159(2):619–33. https://doi.org/10.1016/j.chest.2020.09.070
  4. Bruyneel A, Gallani MC, Tack J, d’Hondt A, Canipel S, Franck S, et al. Impact of COVID-19 on nursing time in intensive care units in Belgium. Intensive Crit Care Nurs. 2021 Feb;62:102967. https://doi.org/10.1016/j.iccn.2020.102967
  5. Cammarota G, Ragazzoni L, Capuzzi F, Pulvirenti S, De Vita N, Santangelo E, et al. Critical Care Surge Capacity to Respond to the COVID-19 Pandemic in Italy: A Rapid and Affordable Solution in the Novara Hospital. Prehosp Disaster Med. 2020 Aug;35(4):431–3. https://doi.org/10.1017/S1049023X20000692
  6. Lefrant JY, Fischer MO, Potier H, Degryse C, Jaber S, Muller L, et al.; French ICU study investigators group. A national healthcare response to intensive care bed requirements during the COVID-19 outbreak in France. Anaesth Crit Care Pain Med. 2020 Dec;39(6):709–15. https://doi.org/10.1016/j.accpm.2020.09.007
  7. Uppal A, Silvestri DM, Siegler M, Natsui S, Boudourakis L, Salway RJ, et al. Critical Care And Emergency Department Response At The Epicenter Of The COVID-19 Pandemic: new York City’s public health system response to COVID-19 included increasing the number of in-tensive care units, transferring patients between hospitals, and supplementing critical care staff. Health Aff (Millwood). 2020 Aug;39(8):1443–9. https://doi.org/10.1377/hlthaff.2020.00901
  8. Federal Office of Public Helath FOPH. COVID-19 Switzerland [Internet]. 2021 Jul. Available from: www.covid19.admin.ch
  9. Jeitziner MM, Jenni-Moser B, Yok-Ai Q, Thurnheer Zrcher MC, Furrer H, Jakob S. Im-portance of critical care staffing and standard intensive care therapy in the COVID-19 era: a de-scriptive study of the first epidemic wave at a Swiss tertiary intensive care unit. Swiss Med Wkly [Internet]. 2021 Jun 25 [cited 2021 Aug 18]; Available from: https://doi.emh.ch/smw.2021.20529
  10. Primmaz S, Le Terrier C, Suh N, Ventura F, Boroli F, Bendjelid K, et al. Preparedness and Reorganization of Care for Coronavirus Disease 2019 Patients in a Swiss ICU: Characteristics and Outcomes of 129 Patients. Crit Care Explor. 2020 Jul;2(8):e0173. https://doi.org/10.1097/CCE.0000000000000173
  11. Swiss Society of Intensive Care Medicine. 2021. Available from: www.sgi-ssmi.ch/de/coivd19.html
  12. Aiken LH, Sloane DM, Bruyneel L, Van den Heede K, Griffiths P, Busse R, et al.; RN4CAST consortium. Nurse staffing and education and hospital mortality in nine European countries: a retrospective observational study. Lancet. 2014 May;383(9931):1824–30. https://doi.org/10.1016/S0140-6736(13)62631-8
  13. Needleman J, Buerhaus P, Pankratz VS, Leibson CL, Stevens SR, Harris M. Nurse staffing and inpatient hospital mortality. N Engl J Med. 2011 Mar;364(11):1037–45. https://doi.org/10.1056/NEJMsa1001025
  14. Rae PJ, Pearce S, Greaves PJ, Dall’Ora C, Griffiths P, Endacott R. Outcomes sensitive to critical care nurse staffing levels: A systematic review. Intensive Crit Care Nurs. 2021 Dec;67(Jul):103110. https://doi.org/10.1016/j.iccn.2021.103110
  15. Neuraz A, Guérin C, Payet C, Polazzi S, Aubrun F, Dailler F, et al. Patient Mortality Is Associated With Staff Resources and Workload in the ICU: A Multicenter Observational Study. Crit Care Med. 2015 Aug;43(8):1587–94. https://doi.org/10.1097/CCM.0000000000001015
  16. West E, Barron DN, Harrison D, Rafferty AM, Rowan K, Sanderson C. Nurse staffing, medical staffing and mortality in Intensive Care: an observational study. Int J Nurs Stud. 2014 May;51(5):781–94. https://doi.org/10.1016/j.ijnurstu.2014.02.007
  17. Shekelle PG. Nurse-patient ratios as a patient safety strategy: a systematic review. Ann Intern Med. 2013 Mar;158(5 Pt 2 5_Part_2):404–9. https://doi.org/10.7326/0003-4819-158-5-201303051-00007
  18. Lasater KB, Sloane DM, McHugh MD, Cimiotti JP, Riman KA, Martin B, et al. Evaluation of hospital nurse-to-patient staffing ratios and sepsis bundles on patient outcomes. Am J Infect Control. 2021 Jul;49(7):868–73. https://doi.org/10.1016/j.ajic.2020.12.002
  19. Xi J, Zeng L, Li S, Ai Y, He X, Kang Y, et al. COVID-19 mortality in ICUs associated with critical care staffing. Burns Trauma. 2021 Apr;9:tkab006. https://doi.org/10.1093/burnst/tkab006
  20. Wendel Garcia PD, Aguirre-Bermeo H, Buehler PK, Alfaro-Farias M, Yuen B, David S, et al.; RISC-19-ICU Investigators. Implications of early respiratory support strategies on disease progression in critical COVID-19: a matched subanalysis of the prospective RISC-19-ICU cohort. Crit Care. 2021 May;25(1):175. https://doi.org/10.1186/s13054-021-03580-y
  21. Harrell FE. Regression Modeling Strategies: With Applications to Linear Models, Logistic and Ordinal Regression, and Survival Analysis [Internet]. Cham: Springer International Publishing; 2015 [cited 2021 Aug 18]. (Springer Series in Statistics). Available from: http://link.springer.com/10.1007/978-3-319-19425-7
  22. Austin PC, Rothwell DM, Tu JV. A Comparison of Statistical Modeling Strategies for Analyz-ing Length of Stay after CABG Surgery. Health Serv Outcomes Res Methodol. 2002;3(2):107–33. https://doi.org/10.1023/A:1024260023851
  23. Lasater KB, Aiken LH, Sloane DM, French R, Martin B, Reneau K, et al. Chronic hospital nurse understaffing meets COVID-19: an observational study. BMJ Qual Saf. 2021 Aug;30(8):639–47. https://doi.org/10.1136/bmjqs-2020-011512
  24. Aiken LH, Clarke SP, Sloane DM, Sochalski J, Silber JH. Hospital nurse staffing and patient mortality, nurse burnout, and job dissatisfaction. JAMA. 2002 Oct;288(16):1987–93. https://doi.org/10.1001/jama.288.16.1987
  25. Needleman J, Buerhaus P, Mattke S, Stewart M, Zelevinsky K. Nurse-staffing levels and the quality of care in hospitals. N Engl J Med. 2002 May;346(22):1715–22. https://doi.org/10.1056/NEJMsa012247
  26. Bergman L, Falk A, Wolf A, Larsson I. Registered nurses’ experiences of working in the inten-sive care unit during the COVID ‐19 pandemic. Nurs Crit Care. 2021 May 10;nicc.12649.
  27. Griffiths P, Ball J, Drennan J, Dall’Ora C, Jones J, Maruotti A, et al. Nurse staffing and patient outcomes: strengths and limitations of the evidence to inform policy and practice. A review and discussion paper based on evidence reviewed for the National Institute for Health and Care Excellence Safe Staffing guideline development. Int J Nurs Stud. 2016 Nov;63:213–25. https://doi.org/10.1016/j.ijnurstu.2016.03.012
  28. Taccone FS, Goethem NV, De Pauw R, Van Beckhoven D, Meyfroidt G, Blot K. Organization-al characteristics: Effect on outcome of ICU COVID-19 patients in Belgium – Authors’ reply. Lancet Reg Health - Eur. 2021 Apr;3:100070.
  29. Bravata DM, Perkins AJ, Myers LJ, Arling G, Zhang Y, Zillich AJ, et al. Association of Intensive Care Unit Patient Load and Demand With Mortality Rates in US Department of Veterans Affairs Hospitals During the COVID-19 Pandemic. JAMA Netw Open. 2021 Jan;4(1):e2034266. https://doi.org/10.1001/jamanetworkopen.2020.34266
  30. Blackwood B, Alderdice F, Burns K, Cardwell C, Lavery G, O’Halloran P. Use of weaning protocols for reducing duration of mechanical ventilation in critically ill adult patients: Cochrane systematic review and meta-analysis. BMJ. 2011 Mar 11;342(jan13 2):c7237–c7237.
  31. Hugonnet S, Uçkay I, Pittet D. Staffing level: a determinant of late-onset ventilator-associated pneumonia. Crit Care. 2007;11(4):R80. https://doi.org/10.1186/cc5974
  32. Musy SN, Endrich O, Leichtle AB, Griffiths P, Nakas CT, Simon M. The association between nurse staffing and inpatient mortality: A shift-level retrospective longitudinal study. Int J Nurs Stud. 2021 Aug;120:103950. https://doi.org/10.1016/j.ijnurstu.2021.103950
  33. Musy SN, Endrich O, Leichtle AB, Griffiths P, Nakas CT, Simon M. Longitudinal Study of the Variation in Patient Turnover and Patient-to-Nurse Ratio: Descriptive Analysis of a Swiss University Hospital. J Med Internet Res. 2020 Apr;22(4):e15554. https://doi.org/10.2196/15554
  34. Wozniak H, Benzakour L, Moullec G, Buetti N, Nguyen A, Corbaz S, et al. Mental health outcomes of ICU and non-ICU healthcare workers during the COVID-19 outbreak: a cross-sectional study. Ann Intensive Care. 2021 Jul;11(1):106. https://doi.org/10.1186/s13613-021-00900-x
  35. Horby P, Lim WS, Emberson JR, Mafham M, Bell JL, Linsell L, et al.; RECOVERY Collaborative Group. Dexamethasone in Hospitalized Patients with Covid-19. N Engl J Med. 2021 Feb;384(8):693–704. https://doi.org/10.1056/NEJMoa2021436
  36. Axfors C, Schmitt AM, Janiaud P, Van’t Hooft J, Abd-Elsalam S, Abdo EF, et al. Mortality outcomes with hydroxychloroquine and chloroquine in COVID-19 from an international collaborative meta-analysis of randomized trials. Nat Commun. 2021 Apr;12(1):2349. https://doi.org/10.1038/s41467-021-22446-z
  37. Greenland S. Ecologic versus individual-level sources of bias in ecologic estimates of contextual health effects. Int J Epidemiol. 2001 Dec;30(6):1343–50. https://doi.org/10.1093/ije/30.6.1343
  38. Wakefield J. Multi-level modelling, the ecologic fallacy, and hybrid study designs. Int J Epidemiol. 2009 Apr;38(2):330–6. https://doi.org/10.1093/ije/dyp179
  39. Greenland S. A review of multilevel theory for ecologic analyses. Stat Med. 2002 Feb;21(3):389–95. https://doi.org/10.1002/sim.1024

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