Physiological responses to maximal exercise testing and the modified incremental shuttle walk test in adults after thermal injury: a pilot study

Response of Aerobic Capacity to Low-Level Laser Therapy in Burned Patients

BACKGROUND

Severe burns lead to decreased pulmonary function and impaired aerobic capacity for long periods post-injury. Low-level laser therapy is a modality utilized to improve aerobic capacity, enhance exercise performance and increase time until fatigue when utilized before aerobic exercises.

PURPOSE

This work aims to determine the impacts of pre-exercise low-level laser therapy on aerobic capacity in burn cases.

PARTICIPANTS AND METHODS

Sixty adults burned cases of both sexes, aged from 25 to 40 years, with second-degree healed thermal burns, and the total burned body surface area ranged from 20 to 40% participated in this study after complete wound healing. They were randomly categorized into two groups of equal numbers. The study group received low-level laser therapy before aerobic exercises, three sessions/week for 12 weeks, while the control group performed aerobic exercises three times weekly for 12 weeks. All cases received the routine physical treatment program. Aerobic capacity was assessed for both groups by measuring maximum oxygen consumption and time to exhaustion at baseline and twelve weeks following interventions.

FINDINGS

There was a statistically significant rise in the mean values of maximum oxygen usage and time to fatigue after 12 weeks of treatment in both groups. However, after comparison, the improvements in the study group were statistically significant than those in the control group with (p < 0.01), (p < 0.05) respectively.

CONCLUSION

Low-level laser therapy has a beneficial therapeutic impact on promoting aerobic capacity, improving maximum oxygen consumption, and increasing treadmill time in burned cases when preceding aerobic exercises.

Intervention Content and Outcomes of Postdischarge Rehabilitation Programs for Adults Surviving Major Burns: A Systematic Scoping Review

Improvement in burn care has led to more patients surviving the injury but has also led to more burn survivors requiring rehabilitation for a protracted period after discharge. Thus, this review sought to map the intervention content and outcomes associated with existing postdischarge rehabilitation programs for adults surviving major burns. A systematic scoping review approach was utilized. The Template for Intervention Description and Replication (TIDieR) and core outcome set for adult burn survivors were used to guide data extraction following which a narrative synthesis was undertaken. In all, 23 papers were retained in the review. Following discharge and up to 1 year postburn, the components of the rehabilitation programs comprised of physical, psychological, and social components. Beyond 1 year postburn, the rehabilitation programs demonstrated a preponderance of physical therapies. Support for family members was not highlighted in the included studies. Outcomes of rehabilitation programs up to 1 year postburn covered the seven core outcome domains. Outcomes associated with rehabilitation programs beyond 1 year postburn were, however, limited to the perceived quality of life, neuromuscular, and physical role functioning domains. Although most studies reported statistically significant findings, the outcome measures varied across studies which makes it difficult to draw overarching conclusions. The findings suggest that long-term rehabilitation programs for adult burn survivors are lacking. More robust studies are also needed to examine community participation outcomes associated with burns rehabilitation programs. The nature of burns and its far-reaching consequences suggest a patient- and family-centered approach to rehabilitation.

The effect of burn severity on functional capacity in patients with burn injury

BACKGROUND

Burns are traumatic injuries that result in severe tissue damage. A reduction in exercise capacity is the most common functional impairment, although it is not clear to what extent the severity of the burn injury affects the exercise capacity.

OBJECTIVE

The aim of this study was to examine the physiological responses to exercise and to evaluate exercise capacity according to burn severity.

METHODS

The study included a total of 64 burn patients, comprising 33 with moderate injuries (Total body surface area: 9.93 ± 4.73%; mean age: 37 ± 11.93 years) and 31 with major injuries (Total body surface area: 39.03 ± 10.36%; mean age: 41.09 ± 14.96 years). Heart rate, systolic blood pressure, diastolic blood pressure, double product, dyspnea level, oxygen saturation and leg fatigue before and after the shuttle walk test were recorded. Walking distances were measured after the shuttle walk test.

RESULTS

A significant difference was determined between patients with major and moderate burn injuries in respect of the cardiovascular responses to the shuttle walk test. Major burn injury patients had a significantly shorter walking distance than the moderate burn injury patients (p< 0.05).

CONCLUSIONS

Burn injury severity was seen to affect the functional capacity and cardiovascular responses to the shuttle walk test. Shuttle walk test can be preferred to evaluate moderate and major burn injury patients' functional capacity in the acute period of injury.

Determination of lymphocytes surface markers in patients with thermal burns and the influence of burn size on mononuclear cell subsets

Background: Thermal burn injuries impair the host defence system. Hence, in the present study, we aimed at investigating the changes in the number and phenotype of peripheral blood lymphocyte populations (T, B, and natural killer cells) and their subpopulations in patients with thermal burns and determining the relationships with different sizes of total body surface area (TBSA). Methods: Blood samples from 67 patients, admitted to Motahary Burn Center in Tehran, with burns from 30% to more than 70% TBSA were collected on Days 3 and 7 postburn. Lymphocytes and their subpopulations were identified by monoclonal antibodies. The cells were analyzed using flow cytometry. The results were compared with healthy controls. Results: In this study, 3 and 7 days after burn injury, the percentages of CD3+, CD4+ and CD8+ lymphocyte significantly decreased, CD4+/CD8+ ratios were below the normal range, and CD19+ (B cells) significantly increased. No significant difference was obtained in the mean percentage of CD16+ (NK cells) between Days 3 and 7 postburn. Patients with burns of 30% TBSA or greater (>70%) had a significant reduction in CD3+, CD4+ and CD8+ ( T cells) numbers up to 7 days compared with 3 days after burn injury. Patients with 30% to >70 % TBSA burn failed to show any significant changes in CD4+/CD8+ ratio as well as CD16+ (NK cells) 3 to 7 days after burn. In patients with burns more than 30% to>70% TBSA, CD19+ (B cells) number changes were found to be complicated after 3 and 7 days. Conclusion: The results of this study suggest that alterations of immune cell surface markers and TBSA% can reflect postburn lymphocyte activation.

Does the incremental shuttle walk test require maximal effort in young obese women?

Obesity is a chronic disease with a multifaceted treatment approach that includes nutritional counseling, structured exercise training, and increased daily physical activity. Increased body mass elicits higher cardiovascular, ventilatory and metabolic demands to varying degrees during exercise. With functional capacity assessment, this variability can be evaluated so individualized guidance for exercise training and daily physical activity can be provided. The aim of the present study was to compare cardiovascular, ventilatory and metabolic responses obtained during a symptom-limited cardiopulmonary exercise test (CPX) on a treadmill to responses obtained by the incremental shuttle walk test (ISWT) in obese women and to propose a peak oxygen consumption (VO2) prediction equation through variables obtained during the ISWT. Forty obese women (BMI ≥30 kg/m2) performed one treadmill CPX and two ISWTs. Heart rate (HR), arterial blood pressure (ABP) and perceived exertion by the Borg scale were measured at rest, during each stage of the exercise protocol, and throughout the recovery period. The predicted maximal heart rate (HRmax) was calculated (210 - age in years) (16) and compared to the HR response during the CPX. Peak VO2 obtained during CPX correlated significantly (P<0.05) with ISWT peak VO2 (r=0.79) as well as ISWT distance (r=0.65). The predictive model for CPX peak VO2, using age and ISWT distance explained 67% of the variability. The current study indicates the ISWT may be used to predict aerobic capacity in obese women when CPX is not a viable option.

Does the Incremental Shuttle Walking Test require maximal effort in healthy subjects of different ages?

OBJECTIVE

To evaluate if the Incremental Shuttle Walking Test (ISWT) requires maximal effort in healthy subjects of different ages.

DESIGN

Cross-sectional.

SETTING

University-based research laboratory.

PARTICIPANTS

331 healthy subjects separated into six groups according to age: G1, 18 to 28 years; G2, 29 to 39 years; G3, 40 to 50 years; G4, 51 to 61 years; G5, 62 to 72 years and; G6, 73 to 83 years.

MAIN OUTCOME MEASURES

Two ISWTs were performed and participants were permitted to run and to exceed 12 levels during the test, if necessary. Heart rate (HR) and symptoms of dyspnoea and fatigue were recorded before and after the test, and the percentage of age-predicted maximal HR (HRmax) was calculated. Maximal effort was defined as HRmax >90% of age-predicted HRmax.

RESULTS

Almost 31% of the subjects exceeded 12 levels in the ISWT. At the end of the test, all groups presented a median [interquartile range] HR greater than 90% of HRmax (G1: 100 [95 to 104]; G2: 100 [96 to 105]; G3: 103 [97 to 108]; G4: 99 [91 to 106]; G5: 96 [87 to 106] and G6: 96 [91 to 109]% HRmax). Regarding symptoms, all groups showed higher values after the test (P<0.05). A multiple logistic regression analysis identified female gender, older age and a lower HR before the test as determinants of not achieving 90% of HRmax at the end of the test.

CONCLUSIONS

The ISWT requires maximal effort in healthy individuals, but for that it is necessary to extend the test beyond twelve levels. Female gender, older age and lower heart rate before the test are the determinants of not reaching maximal effort.

Measurement properties of the incremental shuttle walk test. a systematic review

Background: The incremental shuttle walk test (ISWT) was developed > 20 years ago and has been used to assess peak exercise capacity in a variety of chronic diseases. The aim of this systematic review is to describe the measurement properties of the ISWT in a clinical population.Methods: Of 800 articles identified by electronic and hand searches, 35 were included. Twenty-one articles included data on the validity of the ISWT, 18 on the reliability, four on the responsiveness,and four on the interpretability.Results: Most of the studies were conducted in patients with COPD (n = 13) or cardiac disease(n = 8). For criterion validity, comparisons between distance covered during the ISWT and peak oxygen consumption reported correlations ranging from 0.67 to 0.95 ( P <.01). Intraclass correlation coefficients for test-retest reliability ranged from 0.76 to 0.99. The ISWT was shown to be responsive to pulmonary rehabilitation and bronchodilator administration. The minimal clinically important difference (MCID) in patients with COPD was 48 m. Predictive equations for the distance in the ISWT are available for healthy individuals.Conclusions: The ISWT can be considered a valid and reliable test to assess maximal exercise capacity in individuals with chronic respiratory diseases. The ISWT has been shown to be responsive to pulmonary rehabilitation and bronchodilator use in individuals with COPD, cystic fibrosis,and asthma. Further studies examining responsiveness and the MCID of the ISWT in patients with conditions other than lung diseases are required for the interpretation of interventions in other populations.

Exercise training after burn injury: a survey of practice

Exercise programs capable of contributing positively to the long-term rehabilitation of burn patients should be included in outpatient rehabilitation programs. However, the extent and intensity of the resistance and cardiopulmonary exercise prescribed are unclear. This study was conducted to investigate the existence, design, content, and prescription of outpatient cardiopulmonary and resistance exercise programs within outpatient burn rehabilitation. A survey was designed to gather information on existing exercise programs for burn survivors and to assess the extent to which these programs are included in overall outpatient rehabilitation programs. Three hundred and twenty-seven surveys were distributed in the licensed physical and occupational therapists part of the American Burn Association Physical Therapy/Occupational Therapy Special Interest Group. One hundred and three surveys were completed. Eighty-two percent of respondents indicated that their institutions offered outpatient therapy after discharge. The frequency of therapists' contact with patients during this period varied greatly. Interestingly, 81% of therapists stated that no hospital-based cardiopulmonary endurance exercise programs were available. Patients' physical function was infrequently determined through the use of cardiopulmonary parameters (oxygen consumption and heart rate) or muscle strength. Instead, more subjective parameters such as range of motion (75%), manual muscle testing (61%), and quality of life (61%) were used. Prescription and follow-up assessment of cardiopulmonary endurance training are inconsistent among institutions, underscoring the need for greater awareness of the importance of exercise in any burn rehabilitation program. Identification of cardiopulmonary and progressive resistance parameters for establishing and tracking exercise training is also needed to maximize exercise-induced benefits.