Early Mobility Assessment for Critically Ill Patients

Original Editor - Jess Bell Top Contributors - Jess Bell and Kim Jackson

Introduction

As technology and science evolve in intensive care medicine, more patients are surviving critical illness episodes.[1] However, prolonged stays in intensive care units (ICU) are linked with functional declines, increased morbidity and mortality and increased length of stay in hospital.[2] Patients who survive a stay in ICU often go on to experience various long term challenges on discharge, some psychological (i.e. cognitive impairment, post traumatic stress disorder, persistent anxiety),[3] as well as social, financial and physical impairments, including  ICU acquired weakness,[1] decreased physical function and a decrease in quality of life.[3] These long lasting sequelae are  referred to as post-intensive care syndrome.[1]

It has been found that early mobility (EM) programmes can have a positive impact on these factors.[2] Mobilisation is described as physical activity which results in certain physiological effects.[4][5] It is energy consuming and includes various activities that produce movement (such as actively moving limbs, actively rolling in bed, sitting on the edge of the bed etc).[6]

What is Early Mobility?

Early Mobility (EM) is defined as mobilisation started within 24-48 hours of admission into ICU.[7] It is a safe and achievable practice that has the potential to mitigate the effects of critical illness on several body systems.[8]

EM consists of a series of planned movements that are progressed in a sequential manner.[2] It is commenced with minimal or no participation from the patient. It can also be safely implemented for mechanically ventilated patients and patients receiving continuous hemofiltration.[9] A comprehensive assessment enables the physiotherapist and other members of the mobility team to make an informed decision on the individual mobility requirement of the patient.[10]

[11]

Levels of mobility

Robust mobility protocols have been developed to guide critical care clinicians in EM.[2][12][13][14][15] It is important to liaise with every member of the team to ensure a flow of communication when planning interventions. Goals should be set with the patient and these should always follow the SMART (Specific, Measureable, Achievable, Realistic and Time bound) and FITT (Frequency, Intensity, Time and Type) principles.[10]  It is important to note that goal setting is not always straightforward.[16] The goal setting process should be undertaken in such a way that the clinician is able to gain an understanding of what is important to the patient.[17]

For more information on Early Mobility in ICU, please click here.

Evidence of Effectiveness for Early Mobility Programmes

Evidence exists for the clinical effectiveness of EM in combating the negative effects associated with prolonged immobility during critical illness. Early progressive mobility programmes can be safely implemented for patients in ICU.[2] These programmes can have a positive impact on many outcomes in critical illness survivors.[18][6][19][20]

In particular, they can improve ventilation, circulation, perfusion, muscle metabolism and alertness,[6] as well as decrease the incidence of delirium, reduce the number of days on a ventilator, decrease the length of hospital stay and improve function on discharge.[3]

Evidence has also shown short-term improvements in physical-related outcomes such as muscle strength and a reduction in the incidence of Intensive Care Unit Acquired Weakness (ICU-AW).[21][22] A review by Stiller provides specific evidence on the efficacy of EM on secondary outcomes such as ICU and hospital length of stay.[23] Although some studies provide contrasting reports,[24][25][26] this has been attributed to poor study quality and a delay in initiation of early mobilization interventions.[10]

Assessing a Patient for Early Mobility

An EM programme must be tailored to suit the patient’s condition. Various mobility protocols have been developed to guide clinical care clinicians (including intensivites, physiotherapists and occupational therapists) when implementing EM.[2][14] A thorough assessment will enable the clinician to determine what level of mobility is achievable and safe for each patient.[10] Strong communication with the MDT is essential when managing ICU patients. As for goal setting, when deciding on management, the SMART principle should be followed.[10]

As discussed in detail below, in order for the therapist to consider the unique factors of every presenting case, the following features should be assessed prior to implementing an EM plan:[10]

  • Medical history
  • Cardio-respiratory fitness / physiological reserve / functional capability
  • Neuromuscular / musculoskeletal status
  • Medications (which may affect mobilisation response)
  • Cognitive function and level of consciousness
  • Motivation and goals, as well as patient expectations
  • Anxiety levels
  • Other procedures required by the patient
  • Existence of any contraindications  

Medical History

Prior to implementing any physiotherapy intervention, it is essential to find out the patient’s medical history. Much of this information will be obtained from the patient’s notes and communication with the patient’s family.[10] Key points to consider include:[10]

  • Impact of this acute / chronic illness on the patient
  • Current level of acuity
  • Presence of comorbidities that may impact on management plan
  • Pre-morid fitness to ensure that EM programmes are realistic and safe
  • Functional capability

Cardio-Respiratory Fitness and Physiological Reserve

Understanding cardio-respiratory fitness and physiological reserves, as well as functional capability will help the therapist to determine  what level of mobility will be sufficient and effective for a particular patient.[10]

It is essential to assess the patient’s current physiological status (i.e heart rate, respiratory rate, blood pressure) and to remember that these readings can change rapidly in ICU. Continuously monitoring is, therefore, essential.[10] Specific safety parameters are discussed below.

Neuromuscular and Musculoskeletal Status

It is important to assess musculoskeletal status, including strength, balance and coordination in order to plan an EM programme. Insufficient strength of the lower limbs or major balance deficits will impact on your treatment planning.[10]

Outcome measures

Using outcome measures early in a patient’s hospital stay (i.e. in ICU) can be beneficial as these measures can be monitored and compared over time.[10] There are a number of outcome measures to assess physical function in ICU survivors, but one study by Parry and colleagues found that the Physical Function in Intensive Care Test and Functional Status Score for the ICU appear to be promising measures when assessing physical function in ICU.[27]

Medications

Certain types of medications, such as vasopressors,[28] might hamper the introduction of a mobility programme.

Cognitive Function

Level of consciousness and cognitive function are also vital considerations. They will provide you some insight as to how well the patient may be able to follow instructions.[10]

Motivation and Goals

It is important to consider what the patient’s goals are and his or her level of motivation. Motivation levels will impact patient engagement. It is beneficial to also find out the patient’s expectations. This will help to ensure that the EM programme is patient centred and enhance cooperation.[10]

Once goals are determined, clinicians can identify target areas to direct the intervention (e.g. sitting on the edge of the bed, standing, walking, sitting balance).[10]

Anxiety

Many patients in ICU have been found to be anxious. One study by McKinely and colleagues reported that some anxiety was reported by 85% of patients using the Faces Anxiety Scale.[29] Good communication about the EM programme may help to alleviate some anxieties.[10]

Other Procedures

Any EM programme will have to fit around other procedures that the patient requires, such as dialysis, CT scans, wound dressings and blood transfusions. It is important to liaise with all members of the MDT, so that the EM programme can be timed effectively around other interventions.[10]

The physiotherapist will need to consider if the patient is prepared generally for an EM intervention. Questions to consider include: does the patient need to eat? Will catheters need to be removed or changed? Will the patient need cleaning or covering?[10]

Contraindications

It is important to rule out contraindications before implementing an EM programme which are discussed in detail below. When assessing a patient’s ability to engage in an EM programme, various guidelines exist to highlight specific contraindications.[14][28]

Physiotherapists will need to re-evaluate the patient throughout a treatment session and make adjustments as needed to ensure patient safety.[10]

Safety Guidelines for EM Programmes

Cardiovascular system

Key considerations are the heart rate - the patient should not be tachycardic (i.e. > 130 bpm) or bradycardic (i.e. < 40 bpm).[28] It is also necessary to assess for signs of chronotropic incompetence. Chronotropic incompetence is defined as the inability of the heart to increase its rate in relation to increased activity / demand, which is a common problem for patients with cardiovascular disease.[30] When mobilising an ICU patient, it would be expected that the patient’s heart rate increase due to exertion.[10]

You must also check the patient’s blood pressure prior to any EM programme. If the patient’s systolic blood pressure is above 180 mm Hg an EM programme would need to be terminated.[28]

Most patients in ICU will have a target mean arterial pressure (MAP).[10] MAP indicates the level of blood supply to the organs. According to the American College of Critical Care Medicine (ACCM) guidelines, a MAP of 60-65 mm HG is necessary for organ perfusion.[31] Adler and Malone state that EM should be terminated if MAP is less than 65 mm Hg or more than 110 mm Hg.[28] However, these figures may be individualised to each patient. When carrying out an EM programme, the patient’s BP must remain within the limits of their target MAP.[10]

It is also important to check if a patient is on vasopressors as this will provide an indication of their level of stability / dependence.[10] Vasopressors increase vasoconstriction, which results in increased systemic vascular resistance (SVR). This will increase the MAP and, in turn, improve perfusion to the organs.[31] The ACCM guidelines state that if MAP does not increase to around 60 mm HG after fluid resuscitation, then vasopressors should be initiated.[31] Adler and Malone note that the presence of vasopressor medication, new vasopressor and an escalating dose of vasopressor medication is a contraindication to EM.[28]

Respiratory Status

You will need to check the patient’s respiratory status. Respiratory rate will be the first indication of respiratory distress.[10] A respiratory rate of less than 5 breaths per minute or greater than 40 breaths per minute would require the EM programme to terminate.[28] SpO2 should be more than 88-90% and a drop of more than 4% would require the session to terminate.[28]

When the patient is on a mechanical ventilator, you will need to check the fraction of inspired oxygen (FiO2). Typically, an FiO2 of more than 60 would be unsafe for EM.[28] Any mobility programme increases a patient’s oxygen demand. If the patient’s baseline oxygen demands are very high (i.e. an FiO2 of > 60) the EM programme could destabilise the patient.[10] Positive End Expiratory Pressure (PEEP) levels higher than 10 are not considered safe for an EM programme.[28]

Level of sedation is a key consideration before implementing any EM programme. If a patient is deeply sedated, it is not considered safe to mobilise him or her.[10] A Richmond Agitation Sedation Scale (RASS) score of less than 3 is considered unsafe for EM, as are levels of agitation requiring additional sedative medication (i.e. an RASS of > 2).[28]

It is also essential to consider what a patient tells you. EM should be terminated if a patient complains of intolerable dyspnoea on exertion.[28] In such cases, it is important to determine if there are other challenges or factors that are causing these symptoms.[10]

These and other criteria for terminating or non initiating a mobilisation session are summarised in the table below based on articles by Adler and Malone and Hodgson and colleagues.[28][14]

Safety Guidelines for Early Mobility[10][14][28]

Cardiovascular system Heart rate

>70% age predicted maximum heart rate

>20% decrease in resting heart rate

<40 beats/minutes; >130 beats/minutes

New onset dysrhythmia

New anti-arrhythmia medication

New myocardial infarction

Blood Pressure

Systolic blood pressure >180mmHg

>20% decrease in systolic blood pressure / diastolic blood pressure

Orthostatic hypotension

Mean Arterial Pressure  < 65mmHg or > 110mmHg

Presence of vasopressor medication; new vasopressor or escalating dose of vasopressor medication

Respiratory system Respiratory rate

<5 breaths/minute; >40 breaths/minute

Pulse oximetry (SP02- i.e. saturation of peripheral oxygen)

>4% decrease

<90%

<88 in COPD patients

Mechanical ventilator parameters Fraction of inspired oxygen (FiO2) >0.60

PEEP ≥10

Patient-ventilator asynchrony

Patient factors Sedation level (measured using RASS) ≤ 3

Agitation requiring addition or escalation of sedative medication; RASS ≥ 2

Complaints of intolerable dyspnea on exertion

Refusal to participate in mobility session

Summary

EM programmes may be carried out safely in ICU and can confer many benefits to patients. However, every patient needs to be carefully and regularly assessed in order to ensure that the programme is safe. For more information on implementing EM programmes in ICU, click here.

References

  1. 1.0 1.1 1.2 Clarissa C, Salisbury L, Rodgers S, Kean S. Early mobilisation in mechanically ventilated patients: a systematic integrative review of definitions and activities. J Intensive Care. 2019;7:3.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Perme C, Chandrashekar R. Early mobility and walking program for patients in intensive care units: creating a standard of care. Am J Crit Care. 2009;18(3):212-221.
  3. 3.0 3.1 3.2 Linke CA, Chapman LB, Berger LJ, Kelly TL, Korpela CA, Petty MG. Early Mobilization in the ICU: A Collaborative, Integrated Approach. Crit Care Explor. 2020;2(4):e0090. 
  4. Iwashyna TJ, Hodgson CL. Early mobilization in ICU is far more than just exercise. The Lancet. 2016; 388(10052): 1351‐1352.
  5. Lai CC, Chou W, Chan KS, Cheng KC, Yuan KS, Chao CM et al. Early Mobilization Reduces Duration of Mechanical Ventilation and Intensive Care Unit Stay in Patients With Acute Respiratory Failure. Arch Phys Med Rehabil. 2017;98(5):931-939.
  6. 6.0 6.1 6.2 Arias-Fernández P, Romero-Martin M, Gómez-Salgado J, Fernández-García D. Rehabilitation and early mobilization in the critical patient: systematic review. J Phys Ther Sci. 2018;30(9):1193-1201.
  7. Anekwe DE, Koo KK, de Marchie M, Goldberg P, Jayaraman D, Spahija J. Interprofessional Survey of Perceived Barriers and Facilitators to Early Mobilization of Critically Ill Patients in Montreal, Canada. J Intensive Care Med. 2019;34(3):218-226. 
  8. Nydahl P, Sricharoenchai T, Chandra S, et al. Safety of Patient Mobilization and Rehabilitation in the Intensive Care Unit. Systematic Review with Meta-Analysis. Ann Am Thorac Soc. 2017;14(5):766-777. 
  9. Damluji A, Zanni JM, Mantheiy E, Colantuoni E, Kho ME, Needham DM. Safety and feasibility of femoral catheters during physical rehabilitation in the intensive care unit. J Crit Care. 2013;28(4):535.e9-535.e5.35E15. 
  10. 10.00 10.01 10.02 10.03 10.04 10.05 10.06 10.07 10.08 10.09 10.10 10.11 10.12 10.13 10.14 10.15 10.16 10.17 10.18 10.19 10.20 10.21 10.22 10.23 10.24 10.25 10.26 10.27 Okeke C. Early Mobility Assessment for Critically Ill Patients Course. Physioplus. 2020.
  11. John Hopkins Medicine. Johns Hopkins Medicine: Early Mobility in the ICU. Available from https://www.youtube.com/watch?v=D53gygWRhLM [last accessed 18/09/2020]
  12. Vollman KM. Understanding critically ill patients hemodynamic response to mobilization: using the evidence to make it safe and feasible. Crit Care Nurs Q. 2013;36(1):17-27. 
  13. Davis J, Crawford K, Wierman H, et al. Mobilization of ventilated older adults. J Geriatr Phys Ther. 2013;36(4):162-168. 
  14. 14.0 14.1 14.2 14.3 14.4 Hodgson CL, Stiller K, Needham DM, et al. Expert consensus and recommendations on safety criteria for active mobilization of mechanically ventilated critically ill adults. Crit Care. 2014;18(6):658. 
  15. Kho ME, Molloy AJ, Clarke FJ, Ajami D, McCaughan M, Obrovac K, Cook DJ. TryCYCLE: A prospective study of the safety and feasibility of early in‐bed cycling in mechanically ventilated patients. PLOS One 2016; 11(12): 1-17.
  16. Schoeb V, Staffoni L, Parry R, Pilnick A. "What do you expect from physiotherapy?": a detailed analysis of goal setting in physiotherapy. Disabil Rehabil. 2014;36(20):1679-1686.
  17. Melin J, Nordin Å, Feldthusen C, Danielsson L. Goal-setting in physiotherapy: exploring a person-centered perspective [published online ahead of print, 2019 Aug 26]. Physiother Theory Pract. 2019;1-18.
  18. Martínez-Velilla N, Cadore EL, Casas-Herrero Á, Idoate-Saralegui F, Izquierdo M. Physical Activity and Early Rehabilitation in Hospitalized Elderly Medical Patients: Systematic Review of Randomized Clinical Trials. J Nutr Health Aging. 2016;20(7):738-751. 
  19. McWilliams D, Jones C, Atkins G, et al. Earlier and enhanced rehabilitation of mechanically ventilated patients in critical care: A feasibility randomised controlled trial. J Crit Care. 2018;44:407-412. 
  20. Anekwe DE, Milner SC, Bussières A, de Marchie M, Spahija J. Intensive care unit clinicians identify many barriers to, and facilitators of, early mobilisation: a qualitative study using the Theoretical Domains Framework. J Physiother. 2020;66(2):120-127. 
  21. Fuke R, Hifumi T, Kondo Y, et al. Early rehabilitation to prevent postintensive care syndrome in patients with critical illness: a systematic review and meta-analysis. BMJ Open. 2018;8:e019998.
  22. Anekwe DE, Biswas S, Bussières A, Spahija J. Early rehabilitation reduces the likelihood of developing intensive care unit-acquired weakness: a systematic review and meta-analysis. Physiotherapy. 2020;107:1-10. 
  23. Stiller K. Physiotherapy in intensive care: an updated systematic review. Chest. 2013;144(3):825-847. 
  24. Denehy L, Skinner EH, Edbrooke L, 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. 
  25. Moss M, Nordon-Craft A, Malone D, et al. A Randomized Trial of an Intensive Physical Therapy Program for Patients with Acute Respiratory Failure. Am J Respir Crit Care Med. 2016;193(10):1101-1110. 
  26. Tipping CJ, Harrold M, Holland A, Romero L, Nisbet T, Hodgson CL. The effects of active mobilisation and rehabilitation in ICU on mortality and function: a systematic review. Intensive Care Med. 2017;43(2):171-183. 
  27. Parry SM, Puthucheary ZA. The impact of extended bed rest on the musculoskeletal system in the critical care environment. Extrem Physiol Med. 2015;4:16.
  28. 28.00 28.01 28.02 28.03 28.04 28.05 28.06 28.07 28.08 28.09 28.10 28.11 28.12 28.13 Adler J, Malone D. Early mobilization in the intensive care unit: a systematic review. Cardiopulm Phys Ther J. 2012;23(1):5-13.
  29. McKinley S, Stein-Parbury J, Chehelnabi A, Lovas J. Assessment of anxiety in intensive care patients by using the Faces Anxiety Scale. Am J Crit Care. 2004;13(2):146-152.
  30. Brubaker PH, Kitzman DW. Chronotropic incompetence: causes, consequences, and management. Circulation. 2011;123(9):1010-1020.
  31. 31.0 31.1 31.2 VanValkinburgh D, Kerndt CC, Hashmi MF. Inotropes And Vasopressors. [Updated 2020 Jun 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482411/