Six-Minute Walk Distance After Critical Illness: A Systematic Review and Meta-Analysis

Abstract

Background and Objectives:

Impaired physical functioning is common and long lasting after an intensive care unit (ICU) admission. The 6-minute walk test (6MWT) is a validated and widely used test of functional capacity. This systematic review synthesizes existing data in order to: (1) evaluate 6-minute walk distance (6MWD) in meters over longitudinal follow-up after critical illness, (2) compare 6MWD between acute respiratory distress syndrome (ARDS) versus non-ARDS survivors, and (3) evaluate patient- and ICU-related factors associated with 6MWD.

Data Sources:

Five databases (PubMed, EMBASE, Cumulative Index of Nursing and Allied Health Literature, PsychINFO, and Cochrane Controlled Trials Registry) were searched to identify studies reporting 6MWT after hospital discharge in survivors from general (ie, nonspeciality) ICUs. The last search was run on February 14, 2018. Databases were accessed via Johns Hopkins University Library.

Data Extraction and Synthesis:

Pooled mean 6MWD were reported, with separate linear random effects models used to evaluate associations of 6MWD with ARDS status, and patient- and ICU-related variables. Twenty-six eligible articles on 16 unique participant groups were included. The pooled mean (95% confidence interval [CI]) 6MWD results at 3- and 12-months post discharge were 361 (321-401) and 436 (391-481) meters, respectively. There was a significant increase in 6MWD at 12 months compared to 3 months (P = .017). In ARDS versus non-ARDS survivors, the mean (95% CI) 6MWD difference over 3-, 6-, and 12-month follow-up was 73 [13-133] meters lower. Female sex and preexisting comorbidity also were significantly associated with lower 6MWD, with ICU-related variables having no consistent associations.

Conclusions:

Compared to initial assessment at 3 months, significant improvement in 6MWD was reported at 12 months. Female sex, preexisting comorbidity, and ARDS (vs non-ARDS) were associated with lower 6MWT results. Such factors warrant consideration in the design of clinical research studies and in the interpretation of patient status using the 6MWT.

Keywords

intensive care critical illness physical function 6-minute walk test physical recovery

Get full access to this article

View all access options for this article.

References

Needham

Davidson

Cohen

, et al. Improving long-term outcomes after discharge from intensive care unit: report from a stakeholders’ conference. Crit Care Med. 2012;40(2):502–509.

Herridge

Tansey

Matte

, et al. Functional disability 5 years after acute respiratory distress syndrome. N Engl J Med. 2011;364(14):1293–1304.

Latronico

Herridge

Hopkins

, et al. The ICM research agenda on intensive care unit-acquired weakness. Intensive Care Med. 2017;43(9):1270–1281.

Chan

Pfoh

Denehy

, et al. Construct validity and minimal important difference of 6-minute walk distance in survivors of acute respiratory failure. Chest. 2015;147(5):1316–1326.

Moher

Liberati

Tetzlaff

Altman

. The preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. Open Med. 2009;3(3):e123–e130.

Turnbull

Rabiee

Davis

, et al. Outcome measurement in ICU survivorship research from 1970-2013: a scoping review of 425 publications. Crit Care Med. 2016;44(7):1267–1277.

Higgins

JPT

Altman

Gøtzsche

, et al. The Cochrane collaboration’s tool for assessing risk of bias in randomised trials. BMJ. 2011;343:d5928.

Wells

Shea

O’Connell

, et al. The Newcastle-Ottawa Scale (NOS) for assessing the quality of non-randomised studies in meta-analyses. http://www.ohri.ca/programs/clinical_epidemiology/oxford.asp. Accessed July 2018.

McWilliams

Atkinson

Carter

Foex

Benington

Conway

. Feasibility and impact of a structured, exercise-based rehabilitation programme for intensive care survivors. Physiother Theory Pract. 2009;25(8):566–571.

10.

Elliott

McKinley

Alison

, et al. Health-related quality of life and physical recovery after a critical illness: a multi-centre randomised controlled trial of a home-based physical rehabilitation program. Critical Care. 2011;15(3):R142–R142.

11.

Wan

Wang

Liu

Tong

. Estimating the sample mean and standard deviation from the sample size, median, range and/or interquartile range. BMC Med Res Methodol. 2014;14(1):135.

12.

Pfoh

Wozniak

Colantuoni

, et al. Physical declines occurring after hospital discharge in ARDS survivors: a 5-year longitudinal study. Intensive Care Med. 2016;42(10):1557–1566.

13.

Haines

Berney

Warrillow

Denehy

. Long-term recovery following critical illness in an Australian cohort. J Intensive Care. 2018;6:8.

14.

Dinglas

Hopkins

Wozniak

, et al. One-year outcomes of rosuvastatin versus placebo in sepsis-associated acute respiratory distress syndrome: prospective follow-up of SAILS randomised trial. Thorax. 2016;71(5):401–410.

15.

Jones

Eddleston

McCairn

, et al. Improving rehabilitation after critical illness through outpatient physiotherapy classes and essential amino acid supplement: a randomized controlled trial. J Crit Care. 2015;30(5):901–907.

16.

Denehy

Skinner

Edbrooke

, et al. Exercise rehabilitation for patients with critical illness: a randomized controlled trial with 12 months of follow-up. Crit Care. 2013;17(4):R156.

17.

Wright

Thomas

Watson

, et al. Intensive versus standard physical rehabilitation therapy in the critically ill (EPICC): a multicentre, parallel-group, randomised controlled trial. Thorax. 2018;73(3):213–221.

18.

Wang

Gao

. Assessment of 1-year outcomes in survivors of severe acute respiratory distress syndrome receiving extracorporeal membrane oxygenation or mechanical ventilation: a prospective observational study. Chin Med J (Engl). 2017;130(10):1161–1168.

19.

Viana

RCTP

Pincelli

Pizzichini

, et al. Chronic obstructive pulmonary disease exacerbation in the intensive care unit: clinical, functional and quality of life at discharge and 3 months of follow up. Rev Bras Ter Intensiva. 2017;29(1):47–54.

20.

Das Neves

Vasquez

Loudet

, et al. Symptom burden and health-related quality of life among intensive care unit survivors in Argentina: a prospective cohort study. J Crit Care. 2015;30(5):1049–1054.

21.

Connolly

Thompson

Douiri

Moxham

Hart

. Exercise-based rehabilitation after hospital discharge for survivors of critical illness with intensive care unit-acquired weakness: a pilot feasibility trial. J Crit Care. 2015;30(3):589–598.

22.

Fan

Dowdy

Colantuoni

, et al. Physical complications in acute lung injury survivors: a two-year longitudinal prospective study. Crit Care Med. 2014;42(4):849–859.

23.

Needham

Wozniak

Hough

, et al. Risk factors for physical impairment after acute lung injury in a national, multicenter study. AJRCCM. 2014;189(10):1214–1224.

24.

Needham

Dinglas

Morris

, et al. Physical and cognitive performance of patients with acute lung injury 1 year after initial trophic versus full enteral feeding. EDEN trial follow-up. AJRCCM. 2013;188(5):567–576.

25.

Denehy

Berney

Whitburn

Edbrooke

. Quantifying physical activity levels of survivors of intensive care: a prospective observational study. Phys Ther. 2012;92(12):1507–1517.

26.

Denehy

Nordon-Craft

Edbrooke

, et al. Outcome measures report different aspects of patient function three months following critical care. Intensive Care Med. 2014;40(12):1862–1869.

27.

Chiumello

Taccone

Berto

, et al. Long-term outcomes in survivors of acute respiratory distress syndrome ventilated in supine or prone position. Intensive Care Med. 2012;38(2):221–229.

28.

Alison

Kenny

King

, et al. Repeatability of the six-minute walk test and relation to physical function in survivors of a critical illness. Phys Ther. 2012;92(12):1556–1563.

29.

Aitken

Burmeister

McKinley

, et al. Physical recovery in intensive care unit survivors: a cohort analysis. Am J Crit Care. 2015;24(1):33–39; quiz 40.

30.

Herridge

Cheung

Tansey

, et al. One-year outcomes in survivors of the acute respiratory distress syndrome. NEJM. 2003;348(8):683–693.

31.

Cheung

Tansey

Tomlinson

, et al. Two-year outcomes, health care use, and costs of survivors of acute respiratory distress syndrome. AJRCCM. 2006;174(5):538–544.

32.

Wilcox

Patsios

Murphy

, et al. Radiologic outcomes at 5 years after severe ARDS. Chest. 2013;143(4):920–926.

33.

Masclans

Roca

Munoz

, et al. Quality of life, pulmonary function, and tomographic scan abnormalities after ARDS. Chest. 2011;139(6):1340–1346.

34.

Schandl

Brattstrom

Svensson-Raskh

Hellgren

Falkenhav

Sackey

. Screening and treatment of problems after intensive care: a descriptive study of multidisciplinary follow-up. Intensive Crit Care Nurs. 2011;27(2):94–101.

35.

Casanova

Celli

Barria

, et al. The 6-min walk distance in healthy subjects: reference standards from seven countries. ERJ. 2011;37(1):150–156.

36.

Enright

Sherrill

. Reference equations for the six-minute walk in healthy adults. AJRCCM. 1998;158(5 pt 1):1384–1387.

37.

Camarri

Eastwood

Cecins

Thompson

Jenkins

. Six minute walk distance in healthy subjects aged 55-75 years. Respir Med. 2006;100(4):658–665.

38.

Da Silva

Morano

Cavalcante

De Andrade

Daher Ede

Pereira

. Exercise capacity impairment in COPD patients with comorbidities. Rev Port Pneumol(2006). 2015;21(5):233–238.

39.

Crisafulli

Costi

Luppi

, et al. Role of comorbidities in a cohort of patients with COPD undergoing pulmonary rehabilitation. Thorax. 2008. 63(6):487.

40.

Spruit

Watkins

Edwards

, et al. Determinants of poor 6-min walking distance in patients with COPD: the ECLIPSE cohort. Respir Med. 2010;104(6):849–857.

41.

Ferrante

Pisani

Murphy

Gahbauer

Leo-Summers

Gill

. Factors associated with functional recovery among older intensive care unit survivors. AJRCCM. 2016;194(3):299–307.

42.

Hope

Adeoye

Chuang

Hsieh

Gershengorn

Gong

. Pre-hospital frailty and hospital outcomes in adults with acute respiratory failure requiring mechanical ventilation. J Critical Care. 2018;44:212–216.

43.

Ferrante

Pisani

Murphy

Gahbauer

Leo-Summers

Gill

. The association of frailty with post ICU disability, nursing home admission and mortality: a longitudinal study. Chest. 2018;153(6):1378–1386.

44.

Parry

Granger

Berney

, et al. Assessment of impairment and activity limitations in the critically ill: a systematic review of measurement instruments and their clinimetric properties. Intensive Care Med. 2015;41(5):744–762.

45.

Needham

Sepulveda

Dinglas

, et al. Core outcome measures for clinical research in acute respiratory failure survivors. An international modified Delphi consensus study. AJRCCM. 2017;196(9):1122–1130.

Supplementary Material

Please find the following supplemental material available below.

For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.

For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.

0.00 MB

0.80 MB