Chest
Volume 128, Issue 4, October 2005, Pages 2511-2520
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Clinical Investigations
Supported Arm Training in Patients Recently Weaned From Mechanical Ventilation

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Study objectives

To evaluate the effects of early exercise training in patients recovering from acute respiratory failure needing mechanical ventilation (MV).

Design

Prospective, randomized, and controlled study.

Setting

Three respiratory intermediate ICUs (RIICUs).

Patients

Of 228 patients admitted to an RIICU, 66 patients weaned from MV from > 48 to < 96 h were considered eligible and enrolled in the study.

Intervention

Sixty-six patients were randomized to either supported arm exercise training plus general physiotherapy (gPT) [group 1, 32 patients] or to gPT alone (group 2, 34 patients).

Measurements and results

Twenty-five patients in each group completed the protocol. Group 1 showed a greater improvement in exercise capacity, as assessed by an arm incremental test (IT) [p = 0.003] and an endurance test (ET) [p = 0.021], compared to group 2. Posttraining maximal inspiratory pressure (MIP) significantly improved in both groups (p < 0.001 and p = 0.003 in groups 1 and 2 respectively; not significant). IT isoworkload dyspnea improved significantly in both groups (p = 0.005 and p = 0.009 in groups 1 and 2, respectively; not significant between groups), whereas IT isoworkload peripheral muscle fatigue (p < 0.001), ET isotime dyspnea (p < 0.01), and ET isotime muscular fatigue (p < 0.005) improved significantly in group 1 but not in group 2. IT improvers (χ2 = 0.004) and ET improvers (χ2 = 0.047) were more frequently observed in group 1 than in group 2. Baseline MIP could discriminate for IT (p = 0.013; odds ratio [OR], 1.116) and ET improvers (p = 0.022; OR, 1.067).

Conclusion

Early upper-limb exercise training is feasible in RIICU patients recently weaned from MV and can enhance the effects of gPT. Baseline inspiratory muscle function is related to exercise capacity improvement.

Section snippets

Materials and Methods

The study was approved by the Ethical Committee of The Salvatore Maugeri Foundation, IRCCS and Gaiato Onlus Villa Pineta. Informed consent was given by each patient.

Patients

Patients with different diagnoses weaned from MV (either invasive or noninvasive) for > 48 to < 96 h were enrolled in the study. COPD was defined according to the American Thoracic Society criteria,14 or on the basis of high probability of the disease (ie, clinical history, physical examination, chest radiograph).

A two-parallel-group, prospective, randomized trial was carried out in 66 consecutive patients weaned from MV (via tracheostomy cannula, n = 55; via nasal or facial masks, n = 11) in

General Characteristics

Demographic and anthropometric characteristics, ICU length of stay before RIICU admission, duration of the weaning process, and RIICU and hospital length of stay were recorded in all patients.

Lung Function

FEV1 and FVC were measured at discharge by means of a mass flow sensor with volume integration ( V˙ max; SensorMedics; Yorba Linda, CA; and Master Scope; Jaeger; Hockberg, Germany) with the patients in the seated position according to standard procedure.18 The predicted values of Quanjer19 were used. Lung function data from 40 of 66 patients (60%) were available. Ten patients did not perform the functional maneuver; in 16 other patients, the obtained functional data were not acceptable and

Arm Exercise Test

Symptom-limited incremental tests (ITs) by arm ergometry were performed on an isotonic arm ergometer (Monark 881; Monark; Stockholm, Sweden) secured to a table at the shoulder level, using the standard 1-min incremental exercise protocol. After stabilization and a 1-min period of unloaded cycling at 40 to 45 cycles per minute, the load was increased by 2.5 W/min. The patients were strongly encouraged to exercise to the point of intolerable breathlessness, discomfort, or exhaustion, until the

Study Protocol

All eligible patients were assessed at baseline. The baseline ITs and ETs were performed by a physician not involved in the weaning process within 48 to 96 h after weaning from MV. After baseline assessments, the enrolled subjects were randomly assigned to one of the two groups by means of a computer-generated randomization list: patients in group 1 (study group) underwent a gPT program with the addition of SAEx on the arm ergometer used for the IT and ET, whereas patients in group 2 (control

Definitions

Completers were patients able to finish the 15 scheduled training sessions, whereas dropouts were patients who stopped prematurely the program due to clinical worsening as well as those patients in which for any reason the final assessment was lacking. Patients showing a postrehabilitation improvement equal to or exceeding the 75th percentile in peak workload during the IT and/or in endurance time during the ET (7.5 W and 10 min for the IT and ET, respectively) were defined as improvers

Statistical Analysis

Statistical analysis was performed using SPSS software (release 12.0, SPSS; Chicago, IL). Descriptive data are shown as mean ± SD. The analyses were conducted on a intention-to-treat (all randomized patients) or per-protocol (all completers) basis. A two-sample t test was used to explore differences in baseline characteristics between intervention and control groups, between improvers and nonimprovers, and between completers and dropouts and to assess differences in changes of parameters

Patients and Reasons for Dropout

The trial profile is shown in Figure 1. During the study period, 228 patients were admitted to the three RIICUs; 33% were COPD and 67% were non-COPD (25% amyotrophic lateral sclerosis and neurologic disease, 24% after cardiac surgery, 8% restrictive pulmonary disease, 7% neuromuscular disease, and 3% other diseases). Thirty-two of 228 patients (14%) died; 34 patients (15%) could not be weaned from MV and were discharged with home MV; 96 patients (42%) did not fulfil inclusion criteria because

Effects of SAEx on Maximal Workload and Endurance

Both groups of patients had a significant improvement in maximum workload during the IT (from 9.7 ± 4.8 to 17 ± 8.8 W [p = 0.0001] and from 8.3 ± 4.4 to 11 ± 6.4 W [p = 0.001] for groups 1 and 2, respectively) [Fig 2top left, A, and top right, B]. Similar results were found for ET: from 6.2 ± 4.5 to 14.1 ± 8.7 min (p = 0.0001) and from 5.7 ± 4 to 9.6 ± 6.4 min (p = 0.001) in groups 1 and 2, respectively (Fig 2, bottom left, C, and bottom right, D). A greater improvement was observed in group 1

Effects of SAEx on Perceived Dyspnea and Muscular Fatigue

Perceived dyspnea as assessed by Borg scale at the same workload of the IT (isoload) after the completion of the rehabilitation program decreased significantly in both groups (from 4.6 ± 2.5 to 3.4 ± 2.7 [p = 0.005] and from 5 ± 3.2 to 3.5 ± 2.5 [p = 0.009] in groups 1 and 2, respectively) [Fig 3, top left, A] without any statistical difference in mean changes between groups (Table 2).

Only SAEx, when compared to a control program, was able to reduce muscular fatigue during IT (from 6.3 ± 2.5 to

Improvers and Nonimprovers

Eleven of 25 patients (44%) in group 1 compared to 2 of 25 patients in group 2 (8%) [χ2 = 0.004] demonstrated an improvement in IT after a rehabilitation program ≥ 75th percentile and were defined as IT improvers. Likewise, improvement of ET after a rehabilitation program was more frequent in group 1 than in group 2 (9 of 25 patients [36%] and 3 of 25 patients [12%] in groups 1 and 2, respectively; χ2 = 0.047). According to these results, the number of patients to be trained with SAEx in

Tracheostomized Patients

When the group of tracheostomized patients (42 of 50 patients) was taken into consideration, previous results were somehow confirmed: mean change in IT was 8.1 ± 7 W in group 1 (gPT plus SAEx) and 2.4 ± 3.2 W in group 2 (gPT alone) [p = 0.002], whereas mean change in ET was 8.9 ± 6.9 min in group 1 (gPT plus SAEx) and 3.9 ± 5 min in group 2 (gPT alone) [p = 0.013].

Discussion

This study shows the following: (1) the early addition of SAEx to gPT is feasible in a high-dependency unit like an RIICU in 30% of patients recently weaned from MV; in addition, 75% of eligible patients completed the study protocol; (2) the addition of SAEx to gPT enhances exercise capacity and reduces symptoms; and (3) baseline inspiratory muscle function is related to exercise capacity improvement. A point of major concern in patients admitted to ICUs and undergoing prolonged MV is muscular

ACKNOWLEDGEMENT

The authors are grateful to physiotherapists Marina Berteni, Mara Paneroni, Sheila Chezzi Silva, Mara Sandrini, Francesca Degli Antoni, and Manuela Piran for their assistance and supervision during the training sessions.

References (36)

  • JacksonNC

    Pulmonary rehabilitation for mechanically ventilated patients

    Crit Care Nurs Clin North Am

    (1991)
  • RiesAL et al.

    Upper extremity exercise training in chronic obstructive pulmonary disease

    Chest

    (1988)
  • PauwelsRA et al.

    Global strategy for the diagnosis, management and prevention of chronic obstructive lung disease: NHLBI/WHO global initiative for chronic obstructive lung disease (GOLD) workshop summary

    Am J Respir Crit Care Med

    (2001)
  • RiesAl et al.

    Effects of pulmonary rehabilitation on physiologic and psychosocial outcomes in patients with chronic obstructive pulmonary disease

    Ann Intern Med

    (1995)
  • ACCP/AACVPR. Pulmonary rehabilitation: joint ACCP/AACVPR evidence-based guidelines

    Chest

    (1997)
  • EpsteinSK et al.

    Ventilatory response to arm elevation: its determinants and use in patients with chronic obstructive pulmonary disease

    Am J Respir Crit Care Med

    (1995)
  • EpsteinSK et al.

    Arm training reduces the V'O2 and V'E cost of unsupported arm exercise and elevation in chronic obstructive pulmonary disease

    J Cardiopulm Rehabil

    (1997)
  • American Thoracic Society. Standards of the diagnosis and care of patients with chronic obstructive pulmonary disease

    Am J Respir Crit Care Med

    (1995)
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