Chronic Burn Physiotherapy Rehabilitation
The Role of the Physiotherapist in the Rehabilitation of the Chronic Burn Patient.
∙ Healing process may continue for up to two years, as scar tissue remodels and matures
∙ May require functional retraining and integration back into the community and activities.
It is important to note that though scar management is initiated in the sub-acute phase, it may need to be continued long term, as many patients suffer from continuing limitation to range of motion (Procter 2010).
5.31 Aerobic and Resistance Training Post Burn
5.311 Rationale for Aerobic and Resistance Training
∙ Low cardiorespiratory endurance has been found to be a concern for all (Willis et al 2011)
∙ Aerobic capacity as measured by VO2 peak and time to fatigue has been found to be lower in adults and children of >15% TBSA at one year post burn, compared to age matched healthy controls (Willis et al 2011; McEntine et al 2006)
∙ Muscular strength and lean body mass has been found to be significantly less in patients suffering from burns of >30% TBSA, particularly in exercises requiring a high velocity (Disseldorp et al 2007; Ebid et al 2012). The systemic effects caused by large surface area burns means that weakness may be global, not just local to the site of the injury (Grisbrook et al 2012b)
∙ Reduced lean body mass, endurance and strength has been associated with limited standing/walking tolerance, reduced upper limb function and lower health related QOL and ability to participate in activities (Grisbrook et al 2012b).
∙ This has been found to persist beyond discharge from hospital despite routine physiotherapy and occupational therapy in hospital (Disseldorp et al 2007). Though protein metabolism begins to normalise 9-12 months post burn, patients are still found
to have significant strength and aerobic related functional impairment at >2 years post burn (Grisbrook et al 2012b).
It is proposed that aerobic capacity and muscular strength is diminished by the following factors
∙ Prolonged bed rest necessary in the early recovery process
∙ Hypermetabolisim, which may lead to *
o Protein catabolism
o Loss of lean body mass
∙ Impaired thermoregulation **
∙ Inhalation injuries and compromised respiratory function***
Recovery of aerobic capacity and strength may also be limited by
∙ Psychosocial factors
(Disseldorp et al 2011; De Lauter et al 2007; Grisbrook et al 2012; Suman and Herndon 2007)
- Hyper metabolism, catabolism, loss of lean body mass and exhaustion
Hypermetabolisim post burn caused by both second and third degree burns, particularly if sepsis follows. This may begin approximately five days post burn, as the metabolic state is initially suppressed by the effects of acute shock, and can persist for up to two years post injury (Jeschke et al 2007; Herndon and Tomkins 2004). The greater the TBSA, the greater the risk and impact of hyper metabolism (Hurt et al 2000). While it may not be recognised in the acute stages, it may give rise to long term complications and functional impairment, particularly with respect to strength and aerobic capacity (De Lauter et al 2007).
A systematic review by Disseldorp et al (2007) found 4 studies involving children with > 40% TBSA
∙ All found a decrease of up to 20% in lean muscle mass compared to age matched controls
∙ Adults with a TBSA >30% suffered a significant decrease in torque, work and power in the quadriceps muscles compared to age matched controls. (De Lauter et al 2007)
Exercise and Hypermetabolism
Though exercise requires an increase in energy expenditure and metabolism for a short period of time no adverse effects have been found with regard to exacerbating hypermetabolism or protein catabolism.
o All studies investigating the effects of exercise on lean body mass found it to increase, particularly with resistance training ( Grisbrook et al 2012b; Suman and Herndon 2007; Suman et al 2001; Przkora et al 2007)
o Suman et al, 2001, found an increase of 15% in resting energy expenditure in children with burns of >40% TBSA who were not treated with resistance and aerobic exercise, while the REE of those who participated in the intervention remained stable.
o Suggested that exercise may have sympathetic nervous system attenuating effects
▪ A balance of resistance and aerobic exercise may cause a decrease in SNS activity, decreasing catabolic effects.
o Exercise is required to integrate dietary amino acids into lean muscle mass (Herndon and Tomkins 2004)
Human skin produces sweat to dissipate heat in response to thermal stress (McEntine et al 2006). A proper sweat response requires functional integrity of the
∙ Sweat glands
∙ Skin circulation
∙ Neural control of the skin (McEntine et al 2006)
Full thickness burns damage the dermal appendages including sweat glands. These are not replaced by grafting. There is also a decreased density of sweat glands in the donor site post grafting (Esselman et al 2007).
However, McEntine et al 2006 found that in 15 children with an average of 55% TBSA there was
∙ No significant difference in core temperature, measured tympanically, pre or post 20 minutes of treadmill exercise at room temperature compared to age matched healthy controls.
∙ No significant difference in average skin temperature between burned and healthy children.
∙ Significantly increased skin temperature in healthy versus burned skin per child.
Austin et al, 2003 studied 3 adults with > 60% TBSA, 3 with between 30-40 TBSA and 2 unburned patients post 1 hr cycling at 35 degrees and 60% humidity
∙ None showed significant intolerance for heat as measured by heart rate and core temperature, measured rectally
∙ No significant difference in whole body sweat rate
∙ Overcompensation by healthy skin in the burned patients.
∙ Suggested physical history was a factor in determining patients’ ability to thermoregulate. Therefore adaptations may occur through training.
However, studies involving heat loads of 40 degrees have found a significant inability to maintain adequate thermoregulation. Due to the small study numbers of the above, and the controversy surrounding the efficacy of measuring core temperature accurately, it is advised that patients are closely monitored initially during aerobic exercise for signs of heat intolerance.
- Inhalation injury and pulmonary insufficiency
Long term pulmonary function is compromised in some patients post severe burn
∙ Lasts several years
∙ Documented in both children and adults (Grisbrook et al 2012a)
∙ Caused by
o Smoke inhalation
o Direct thermal damage to airways
o Pulmonary oedema
o Respiratory tract infection
o Complications from intubation
o Recurrent infection leading to chronic inflammation
Less likely to cause dysfunction in <30% TBSA, no injury over torso, and no inhalation injury
(Willis et al 2011)
Evidence for impact on aerobic and exercise capacity conflicting (Grisbrook et al 2012a). However Willis et al (2011) studied 8 males post > 15% TBSA burns at one year post injury, and found
∙ Significantly decreased FEV1, peak VO2 and time to fatigue, in the burned patients ∙ No significant decrease in SpO2 at baseline or peak VO2- however, the SpO2 of burned patients took significantly longer to stabilise at baseline post exercise. ∙ No significant difference in participation levels in physical activity, though burn survivors were more likely to participate in work rather than leisure activity. ∙ Burns survivors were less likely to participate in vigorous intensity exercise over 9 METs
∙ Therefore, decreased pulmonary function did not prevent them from participating ∙ The lower relative intensity of their exercise may have caused their decreased aerobic capacity.
All of the above factors must be considered as both a contributor to the patients’ loss of strength and aerobic capacity, and a potential limiter of their ability to participate in therapy. Careful monitoring and modification of treatment according to individual response is advised.
5.312 Aerobic Training: The Evidence
Article citation Disseldorp et al, 2011 De Lauteur et al, 2007 Grisbrook et al, 2012 Grisbrook et al, 2012 Paratz et al, 2012 (ab) Przkora et al, 2007 Design Systematic
Eleven articles included
1 RCT<5, 1 non RCT, 2 static group comparison
Oxandrolone, vs osandrolone + exercise, vs exercise + placebo,
7 different cohorts
5 children with exceptionally large TBSA
35 adults mean 37.5 days post burn, mean TBSA 19.3% 9 burn injured adults and 9 age matched healthy controls. 20%+ TBSA, 2 yrs post injury, with remaining functional deficit. 30 patients, mean age 34.3 years, mean TBSA 42.9% 51 children, 7- 17 yrs old, >40% TBSA Interve
Aimed to assess physical fitness post burn, and the effectiveness
of aerobic exercise
12 week rehabilitation programme, 3 x weekly 30 mins. Standard
rehabilitation vs. work to quota and work to tolerance
12 weeks, 3 x weekly, 80 mins.
30 mins of treadmill walking/jogging in intervals (85 vs 65-70 HR max) and resistance exercises.
6weeks, 80 % MHR aerobic training, with 70% three RM
12 week inpatient
physiotherapy twice daily for 1 hr. aerobic and resistance
Aerobic 5 days per week, 20-40 mins, 70-85% VO2peak
Children and adults after extensive
burns score worse than non-burned
controls in all
Max aerobic capacity:
measure, VO2 peak
Burn specific health scale, SF 36, quick DASH 1RM, VO2 peak, shuttle walk
distance, LL function
score, quick dash, burns
Biodex leg extension, 3 RM, VO2 peak, lean body mass,
aspects of fitness.
Burn patients participating in 12 week training
more than those without.
Results Work to tolerance and work to quota significantly
capacity. No significant
improvement in control. No significant
WTQ and WTT
No significant improvement in spirometry values
improvement in VO2 peak and time to fatigue in both groups.
improvement in satisfaction with
Burns patients scored lower on HRQOL and quick dash both before and after the intervention
compared to controls. 5/9 burn patients reached
improvements in BSHS post intervention. No significant increase in DASH
No adverse effects.
improvement s in functional,
LBM increased in all groups except placebo showed average decrease.
highest relative increase. Both exercise and drug only group showed
increase in strength.
increased in the exercise groups, but not those with only steroids/placebo
Limitat ions 4 studies conducted in children with large TBSA burns. Little variation in the protocols
compared, and so no objective evidence of the efficacy of individual
components of exercise.
Low risk of bias in randomisatio n, no discussion of blinding to initial scores. Unable to blind
therapists or patients to the
intervention. Small patient numbers
Small subject numbers, no untreated
blinding not possible
Small subject numbers, no untreated
blinding not possible
Unable to identify the methodologic al rigour of this study, and so results should be interpreted
Low risk of bias in
randomisation, no discussion of blinding which leaves a high risk of bias where a placebo drug is involved.
Table 12 Evidence for Aerobic Training Post Burn
5.313 Aerobic Training Summary and Recommendations for Practice Exercise prescription:
Frequency: The majority of papers which investigated an aerobic intervention used 3 times per week as their frequency (De Lauteur et al 2007; Grisbrook et al 2012). These obtained significant improvements. However, Przkora et al (2007) used a frequency of 5 times per week with children. There have been no studies investigating optimal frequency.
Intensity: All studies used between 65 and 85% predicted heart rate max, with one study using interval training of 120 seconds 85% HRM and 120 seconds of 65-70 HRM. All studies obtained positive effect, with none directly comparing intensities to determine the optimum. De Lauteur et al (2007), concluded that whether the patient gradually increased their intensity by working to a specific quota each week, or if they simply worked at their target heart rate for as long as they could tolerate, there was no significant difference in gains in aerobic capacity.
Type: All interventions used treadmill training, whether walking or running.
Time: All studies recommended the duration of treatment be 12 weeks, with the exception of Paratz et al, 2012, who investigated a high intensity six week programme. However, the specific results of this are unknown. Sessions were 20-40 minutes in length, with the majority using 30 minutes (Grisbrook et al 2012; De Lauteur et al 2007; Przkora et al 2007)
Please note safety considerations Pg 72
5.314 Resistance Training: The Evidence
5.314 Resistance Training Summary and Recommendations for Practice
Exercise prescription: Post two years, Grisbrook et al (2012b) found that burned patients responded to resistance exercise similarly to controls. Therefore, normal guidelines may be adequate.
Frequency: All studies investigating the effects of resistance training used a frequency of three times per week. There have been no studies to investigate the optimum frequency for resistance training in this population. Suman et al (2001), suggested that a break of more than 48 hrs must be given between bouts of resistance training.
o Resistance exercise causes microtrauma to muscles already in a compromised state. o Resistance exercise in burned patients stimulates protein synthesis as in unburned subjects- However; a longer period of recovery may be required for optimum results.
Type/ Intensity: Children: using free weights or resistive machines: 1 set of 50-60% of the patients 3 RM week 1, followed by a progression to 70-75% for week 2-6 (4-10 repetitions), and 80-85% week 7-12, (8-12 repetitions) (Suman et al 2001; Suman and Herndon 2007).
Isokinetic training: 10 reps at 150 degrees per second, using 1-5 sets for the 1st-5th session,6 sets for the 6th-24th session, and 10 sets from 25th to 36th session, with three minute rests between sets. (Ebid et al 2012).
Mixed and functional strength training: Grisbrook et al (2012b) commenced on the biodex, targeting specific muscle groups for the desired functional goal, and progressed to resistive machine and finally free weight training using functional items. Intensity was 50- 60% of 1 RM initially, for 10-15 reps, adjusting as 1 RM increased. While no studies have compared the optimum type/intensity of exercise, this may be the optimum approach. Providing functional exercises may also increase motivation and compliance.
Time: All the studies used a protocol of 12 weeks. There were no studies comparing the efficacy of shorter or longer time frames, however, given that loss of lean body mass is a possible cause of strength loss post burn, an exercise programme of longer than eight weeks is probably required to ensure hypertrophy and optimum gains in the burn patient (Suman et al 2001)
5.316 Safety Considerations for Strength and Aerobic Training:
Initiating aerobic and strength training:
∙ studies stipulated a minimum of six months to two years post burn before initiation of programmes, though many subjects were included who had been burned many years before. These participants all benefited from the interventions.
∙ Suman and Herndon (2007) suggested that the time frame of 6 months post burn was chosen based on clinical experience because by this time paediatric patients with >40% TBSA burns were
o 95% healed
o had had the opportunity to return home
▪ Therefore, more favourable psychological status
∙ There were no studies investigating early training
o With extensive burns, adequate healing of wounds and medical stability required before initiating aerobic/strength exercise
Other safety considerations:
∙ Though exercise has been shown to increase lean body mass, liaison with doctors concerning anabolic steroids and medication and with dieticians regarding optimal nutrition is recommended in order to ensure correct management of hypermetabolisim.
∙ Caution should be used with regard to impaired thermoregulation. Monitoring of heart rate and blood pressure may be advisable, particularly on initiation of exercise and when exercising with additional thermal stress. Manage the environment to minimise thermal stress initially in particular.
∙ Particularly those at risk of reduced pulmonary function post burn (i.e., >30% TBSA, injury to torso, or inhalation injury), monitor SpO2 and RPE during exercise. Allow additional rest periods to allow SpO2 to return to normal levels post exercise, as this has been shown to be delayed.