Factors influencing physical activity and rehabilitation in survivors of critical illness: a systematic review of quantitative and qualitative studies

Purpose

To identify, evaluate and synthesise studies examining the barriers and enablers for survivors of critical illness to participate in physical activity in the ICU and post-ICU settings from the perspective of patients, caregivers and healthcare providers.

Methods

Systematic review of articles using five electronic databases: MEDLINE, CINAHL, EMBASE, Cochrane Library, Scopus. Quantitative and qualitative studies that were published in English in a peer-reviewed journal and assessed barriers or enablers for survivors of critical illness to perform physical activity were included. Prospero ID: CRD42016035454.

Results

Eighty-nine papers were included. Five major themes and 28 sub-themes were identified, encompassing: (1) patient physical and psychological capability to perform physical activity, including delirium, sedation, illness severity, comorbidities, weakness, anxiety, confidence and motivation; (2) safety influences, including physiological stability and concern for lines, e.g. risk of dislodgement; (3) culture and team influences, including leadership, interprofessional communication, administrative buy-in, clinician expertise and knowledge; (4) motivation and beliefs regarding the benefits/risks; and (5) environmental influences, including funding, access to rehabilitation programs, staffing and equipment.

Conclusions

The main barriers identified were patient physical and psychological capability to perform physical activity, safety concerns, lack of leadership and ICU culture of mobility, lack of interprofessional communication, expertise and knowledge, and lack of staffing/equipment and funding to provide rehabilitation programs. Barriers and enablers are multidimensional and span diverse factors. The majority of these barriers are modifiable and can be targeted in future clinical practice.

     

Lung-function tests in neonates and infants with chronic lung disease: tidal breathing and respiratory control

This paper is the fourth in a series of reviews that will summarize available data and critically discuss the potential role of lung-function testing in infants with acute neonatal respiratory disorders and chronic lung disease of infancy. The current paper addresses information derived from tidal breathing measurements within the framework outlined in the introductory paper of this series, with particular reference to how these measurements inform on control of breathing. Infants with acute and chronic respiratory illness demonstrate differences in tidal breathing and its control that are of clinical consequence and can be measured objectively. The increased incidence of significant apnea in preterm infants and infants with chronic lung disease, together with the reportedly increased risk of sudden unexplained death within the latter group, suggests that control of breathing is affected by both maturation and disease. Clinical observations are supported by formal comparison of tidal breathing parameters and control of breathing indices in the research setting.     

Incidence, risk factors and outcome associations of intra-abdominal hypertension in critically ill patients

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are significantly associated with morbidity and mortality. We performed a prospective observational study and applied recently published consensus criteria to measure and describe the incidence of IAH and ACS, identify risk factors for their development and define their association with outcomes. We studied 100 consecutive patients admitted to our general intensive care unit. We recorded relevant demographic, clinical data and maximal (max) and mean intra-abdominal pressure (IAP). We measured and defined IAH and ACS using consensus guidelines. Of our study patients, 42% (by IAPmax) and 38% (by IAPmean) had IAH. Patients with IAH had greater mean body mass index (30.4 ± 9.6 vs 25.4 ± 5.6 kg/m(2), P=0.005), Acute Physiology and Chronic Health Evaluation III score (78.2 ± 28.5 vs 65.5 ± 29.2, P=0.03) and central venous pressure (12.8 ± 4.8 vs 9.2 ± 3.5 mmHg, P <0.001), lower abdominal perfusion pressure (67.6±13.5 vs 79.3 ± 17.3 mmHg, P <0.001) and lower filtration gradient (51.2 ± 14.8 vs 71.6 ± 17.7 mmHg; P <0.001). Risk factors associated with IAH were body mass index =30 (P <0.001), higher central venous pressure (P <0.001), presence of abdominal infection (P=0.005) and presence of sepsis on admission (P=0.035). Abdominal compartment syndrome developed in 4% of patients. IAP was not associated with an increased risk of mortality after adjusting for other confounders. We conclude that, in a general population of critically ill patients, using consensus guidelines, IAH was common and significantly associated with obesity and sepsis on admission. In a minority of patients, IAH was associated with abdominal compartment syndrome. In this cohort IAH was not associated with an increased risk of mortality.     

Hypoalbuminemia and Early Mortality After Lung Transplantation: A Cohort Study

Hypoalbuminemia predicts disability and mortality in patients with various illnesses and in the elderly. The association between serum albumin concentration at the time of listing for lung transplantation and the rate of death after lung transplantation is unknown. We examined 6808 adults who underwent lung transplantation in the United States between 2000 and 2008. We used Cox proportional hazard models and generalized additive models to examine multivariable‐adjusted associations between serum albumin and the rate of death after transplantation. The median follow‐up time was 2.7 years. Those with severe (0.5–2.9 g/dL) and mild hypoalbuminemia (3.0–3.6 g/dL) had posttransplant adjusted mortality rate ratios of 1.35 (95% CI: 1.12–1.62) and 1.15 (95% CI: 1.04–1.27), respectively. For each 0.5 g/dL decrease in serum albumin concentration the 1‐year and overall mortality rate ratios were 1.48 (95% CI: 1.21–1.81) and 1.26 (95% CI: 1.11–1.43), respectively. The association between hypoalbuminemia and posttransplant mortality was strongest in recipients with cystic fibrosis and interstitial lung disease. Hypoalbuminemia is an independent risk factor for death after lung transplantation.     

The Spleen Is the Major Source of Antidonor Antibody‐Secreting Cells in Murine Heart Allograft Recipients

Antibody‐mediated allograft rejection is an increasingly recognized problem in clinical transplantation. However, the primary location of donor‐specific alloantibody (DSA)‐producing cells after transplantation have not been identified. The purpose of this study was to test the contribution of allospecific antibody‐secreting cells (ASCs) from different anatomical compartments in a mouse transplantation model. Fully MHC‐mismatched heart allografts were transplanted into three groups of recipients: nonsensitized wild type, alloantigen‐sensitized wild‐type and CCR5^?/? mice that have exaggerated alloantibody responses. We found that previous sensitization to donor alloantigens resulted in the development of antidonor alloantibody (alloAb) with accelerated kinetics. Nevertheless, the numbers of alloantibody‐secreting cells and the serum titers of antidonor IgG alloantibody were equivalent in sensitized and nonsensitized recipients 6 weeks after transplantation. Regardless of recipient sensitization status, the spleen contained higher numbers of donor‐reactive ASCs than bone marrow at days 7 – 21 after transplantation. Furthermore, individual spleen ASCs produced more antidonor IgG alloantibody than bone marrow ASCs. Taken together, our results indicate that the spleen rather than bone marrow is the major source of donor‐reactive alloAb early after transplantation in both sensitized and nonsensitized recipients.