Effects of exogenous growth hormone on resting pulmonary function in children with thermal injury

Anabolic and anticatabolic agents used in burn care: What is known and what is yet to be learned

Major thermal injury induces profound metabolic derangements secondary to an inflammatory "stress-induced" hormonal environment. Several pharmacological interventions have been tested in an effort to halt the hypermetabolic response to severe burns. Insulin, insulin growth factor 1, insulin growth factor binding protein 3, metformin, human growth hormone, thyroid hormones, testosterone, oxandrolone, and propranolol, among others, have been proposed to have anabolic or anticatabolic effects. The aim of this broad analysis of pharmacological interventions was to raise awareness of treatment options and to help establishing directions for future clinical research efforts. A PubMed search was conducted on the anabolic and anticatabolic agents used in burn care. One hundred and thirty-five human studies published between 1999 and 2017 were included in this review. The pharmacological properties, rationale for the treatments, efficacy considerations and side effect profiles are summarized in the article. Many of the drugs tested for investigational purposes in the severely thermally injured are not yet gold-standard therapies in spite of their potential benefit. Propranolol and oxandrolone have shown great promise but further evidence is still needed to clarify their potential use for anabolic and anticatabolic purposes.

Effect of aquatic versus land based exercise programs on physical performance in severely burned patients: a randomized controlled trial

[Purpose] To compare the effect of an aquatic-based versus a land-based exercise regimen on the physical performance of severely burned patients. [Subjects and Methods] Forty patients suffering from severe burn (total body surface area more than 30%) were recruited from several outpatient clinics in Greater Cairo. Their ages ranged between 20 to 40 years and were randomly assigned into two equal groups: group (A), which received an aquatic based exercise program, and group (B), which received a land-based exercise program. The exercise program, which took place in 12 consecutive weeks, consisted of flexibility, endurance, and lower and upper body training. Physical performance was assessed using 30 seconds chair stand test, stair climb test, 30 meter fast paced walk test, time up and go test, 6-minute walk test and a VO2max evaluation. [Results] Significantly increase in the 30 second chair stand, 6-minute walk, 30 meter fast paced walk, stair climb, and VO2 max tests and significantly decrease in the time up and go test in group A (aquatic based exercise) compared with group B (a land-based exercise) at the post treatment. [Conclusion] Twelve-week program of an aquatic program yields improvement in both physical performance and VO2 max in patients with severe burns.

Long-Term Administration of Oxandrolone Improves Lung Function in Pediatric Burned Patients

Pulmonary dysfunction is a significant contributor to morbidity and mortality in the pediatric burned population. We have previously reported that the administration of a synthetic testosterone derivative, oxandrolone, significantly reduced hypermetabolism, and significantly increased height percentile, bone mineral content, lean body mass, and strength in pediatric burned patients. We hypothesize that the administration of oxandrolone will improve pulmonary function in burned pediatric subjects. A subset of severely burned pediatric subjects from a prospective clinical trial (n = 222) were included in our study (n = 54, 7-18 years, ≥30% TBSA burn). The subjects were previously randomized to either the control arm (n = 35) or the oxandrolone arm (0.1 mg/kg twice/day for 12 months, n = 19). Maximum voluntary ventilation, the ratio between forced expiratory volume and forced vital capacity, and diffusion capacity were measured 6 months following burn injury, and results were compared between burned subjects with and without oxandrolone administration. Maximum expired ventilation (VEmax) was also measured in a subset of burned subjects. Subjects treated with oxandrolone had a significantly higher maximum voluntary ventilation (98 ± 53 L/min vs 115 ± 56 with treatment, P = .03). During maximal exercise, subjects treated with oxandrolone had a significantly higher VEmax compared with untreated subjects (32.0 ± 8.7 L/min vs 43.7 ± 13.6 with treatment, P = .02). The administration of oxandrolone was associated with improved lung function in pediatric burned patients.

Cardiorespiratory Capacity and Strength Remain Attenuated in Children with Severe Burn Injuries at Over 3 Years Postburn

OBJECTIVES

To compare physical capacity and body composition between children with burn injuries at approximately 4 years postburn and healthy, fit children.

STUDY DESIGN

In this retrospective, case-control study, we analyzed the strength, aerobic capacity, and body composition of children with severe burn injuries (n = 40) at discharge, after completion of a 6- to 12-week rehabilitative exercise training program, and at 3-4 years postburn. Values were expressed as a relative percentage of those in age- and sex-matched children for comparison (n = 40 for discharge and postexercise; n = 40 for 3.5 years postburn).

RESULTS

At discharge, lean body mass was 89% of that in children without burn injuries, and exercise rehabilitation restored this to 94% (P < .01). At 3.5 years postburn, lean body mass (94%), bone mineral content (89%), and bone mineral density (93%; each P ≤ .02) remained reduced, whereas total body fat was increased (148%, P = .01). Cardiorespiratory fitness remained lower in children with burn injuries both after exercise training (75%; P < .0001) and 3.5 years later (87%; P < .001). Peak torque (60%; P < .0001) and average power output (58%; P < .0001) were lower after discharge. Although exercise training improved these, they failed to reach levels achieved in healthy children without burns (83-84%; P < .0001) but were maintained at 85% and 82%, respectively, 3.5 years later (P < .0001).

CONCLUSIONS

Although the benefits of rehabilitative exercise training on strength and cardiorespiratory capacity are maintained at almost 4 years postburn, they are not restored fully to the levels of healthy children. Although the underlying mechanism of this phenomenon remains elusive, these findings suggest that future development of continuous exercise rehabilitation interventions after discharge may further narrow the gap in relation to healthy adolescents.

Cardiovascular Dysfunction Following Burn Injury: What We Have Learned from Rat and Mouse Models

Severe burn profoundly affects organs both proximal and distal to the actual burn site. Cardiovascular dysfunction is a well-documented phenomenon that increases morbidity and mortality following a massive thermal trauma. Beginning immediately post-burn, during the ebb phase, cardiac function is severely depressed. By 48 h post-injury, cardiac function rebounds and the post-burn myocardium becomes tachycardic and hyperinflammatory. While current clinical trials are investigating a variety of drugs targeted at reducing aspects of the post-burn hypermetabolic response such as heart rate and cardiac work, there is still a paucity of knowledge regarding the underlying mechanisms that induce cardiac dysfunction in the severely burned. There are many animal models of burn injury, from rodents, to sheep or swine, but the majority of burn related cardiovascular investigations have occurred in rat and mouse models. This literature review consolidates the data supporting the prevalent role that β-adrenergic receptors play in mediating post-burn cardiac dysfunction and the idea that pharmacological modulation of this receptor family is a viable therapeutic target for resolving burn-induced cardiac deficits.

Activities of nonlysosomal proteolytic systems in skeletal and cardiac muscle during burn-induced hypermetabolism

The aim of this study was to assess the activity of nonlysosomal proteolytic systems in skeletal and cardiac muscle during burn-induced hypermetabolism (BHM) in rats. Rats underwent 30% TBSA scald burn or sham injury and were observed for up to 42 days. Body weights and resting energy expenditures were determined weekly. Skeletal (soleus/pectoral) muscle and hearts were harvested on days 0 (=control), 7, 14, 21, and 42 after burn. Calpain, caspase-1, caspase-3/7, caspase-6, caspase-8, caspase-9, and proteasome peptidase activities were measured in tissue extracts. Hypermetabolism developed within 3 weeks after burns, as documented by increased resting energy expenditures and decreased body weights on postburn days 21 to 42 (P < 0.05 vs control). Calpain activities did not show significant alterations. Pan caspase activities increased by time and were significantly increased in skeletal and cardiac muscle extracts during hypermetabolism. Although increases in caspase-1, caspase-8, and caspase-9 activities were predominantly responsible for elevated pan caspase activities in skeletal muscle, increases in caspase-6 activities dominated in the heart. Proteasome peptidase activities in skeletal muscle extracts were not significantly altered. Proteasome peptidase activities in heart extracts increased time dependently and were significantly increased during BHM. Activation of caspase cascades during BHM constitutes a uniform response in skeletal and cardiac muscle and may contribute to enhanced metabolic protein turnover. Activation of myocardial proteasome activities may reflect persistent cardiac stress. Further exploration of caspase cascades and the proteasome as therapeutic targets to influence long-term consequences of BHM appears justified.

Recombinant human growth hormone for treating burns and donor sites

BACKGROUND

Recombinant human growth hormone (rhGH) increases protein synthesis, therefore it is used in burns with a total body surface area (TBSA) greater than 40%, where there is frequently an increase in protein breakdown and a decrease in protein synthesis. This change in protein metabolism correlates with poor wound healing of the burn and donor sites.

OBJECTIVES

To determine the effects of rhGH on the healing rate of burn wounds and donor sites in people with burns.

SEARCH METHODS

For this first update we searched the Cochrane Wounds Group Specialised Register (searched 04 September 2014); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 8); Database of Abstracts of Reviews of Effects (DARE) (The Cochrane Library 2014, Issue 3); Ovid MEDLINE (1950 to September Week 4 2014); Ovid MEDLINE (In-Process & Other Non-Indexed Citations September 8, 2014); Ovid EMBASE (1980 to 2014 Week 35); and EBSCO CINAHL (1982 to 8 September 2014).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing rhGH with any comparator intervention, e.g. oxandrolone or placebo, in adults or children with burns.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed trial quality and extracted data. The primary outcomes were the healing of the burn wound and donor sites and the occurrence of wound infections. The secondary outcomes were mortality rate, length of hospital stay, scar assessment, and adverse events: hyperglycaemia and septicaemia.

MAIN RESULTS

We included 13 RCTs (701 people). Six of the RCTs included only children aged 1 to 18 years and seven involved only adults (from 18 to 65 years of age). The mean TBSA of the included participants was greater than 49%. Twelve studies compared rhGH with placebo and one study compared rhGH with oxandrolone. Two trials found that compared with placebo, burn wounds in adults treated with rhGH healed more quickly (by 9.07 days; 95% confidence interval (CI) 4.39 to 13.76, I² = 0%). The donor site healing time was significantly shorter in rhGH-treated adults compared with placebo-treated participants (by 3.15 days; 95% CI 1.54 to 4.75, I² = 0%). Two studies in children with the outcome of donor site healing time could be pooled and the donor site healing time was shorter in the rhGH-treated children (by 1.70 days; 95% CI 0.87 to 2.53, I² = 0%). No studies reporting the outcome of wound infection were found. The incidence of hyperglycaemia was higher in adults during rhGH treatment compared with placebo (risk ratio (RR) 2.43; 95% CI 1.54 to 3.85), but not in children. Pooling the studies of adults and children yielded a significantly higher incidence of hyperglycaemia in the rhGH-treated participants (RR 2.65; 95% CI 1.68 to 4.16).

AUTHORS' CONCLUSIONS

There is some evidence that using rhGH in people with large burns (more than 40% of the total body surface area) could result in more rapid healing of the burn wound and donor sites in adults and children, and in reduced length of hospital stay, without increased mortality or scarring, but with an increased risk of hyperglycaemia. This evidence is based on studies with small sample sizes and risk of bias and requires confirmation in higher quality, adequately powered trials.

Recombinant human growth hormone for treating burns and donor sites

BACKGROUND

Recombinant human growth hormone (rhGH) increases protein synthesis, therefore it is used in burns with a total body surface area (TBSA) greater than 40%, where there is frequently an increase in protein breakdown and a decrease in protein synthesis. This change in protein metabolism correlates with poor wound healing of the burn and donor sites.

OBJECTIVES

To determine the effects of rhGH on the healing rate of burn wounds and donor sites in people with burns.

SEARCH METHODS

We searched the Cochrane Wounds Group Specialised Register (searched 28 June 2012); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 6); Database of Abstracts of Reviews of Effects (DARE) (The Cochrane Library 2011, Issue 3); Ovid MEDLINE (1950 to June Week 3 2012); Ovid MEDLINE (In-Process & Other Non-Indexed Citations June 27, 2012); Ovid EMBASE (1980 to 2012 Week 25); and EBSCO CINAHL (1982 to 21 June 2012).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing rhGH with any comparator intervention, e.g. oxandrolone or placebo, in adults or children with burns.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed trial quality and extracted data. The primary outcomes were the healing of the burn wound and donor sites and the occurrence of wound infections. The secondary outcomes were mortality rate, length of hospital stay, scar assessment, and adverse events: hyperglycaemia and septicaemia.

MAIN RESULTS

We included 13 RCTs (701 people). Six of the RCTs included only children aged 1 to 18 years and seven involved only adults (from 18 to 65 years of age). The mean TBSA of the included participants was greater than 49%. Twelve studies compared rhGH with placebo and one study compared rhGH with oxandrolone. Two trials found that compared with placebo, burn wounds in adults treated with rhGH healed more quickly (by 9.07 days; 95% confidence interval (CI) 4.39 to 13.76, I² = 0%). The donor site healing time was significantly shorter in rhGH-treated adults compared with placebo-treated participants (by 3.15 days; 95% CI 1.54 to 4.75, I² = 0%). Two studies in children with the outcome of donor site healing time could be pooled and the donor site healing time was shorter in the rhGH-treated children (by 1.70 days; 95% CI 0.87 to 2.53, I² = 0%). No studies reporting the outcome of wound infection were found. The incidence of hyperglycaemia was higher in adults during rhGH treatment compared with placebo (risk ratio (RR) 2.43; 95% CI 1.54 to 3.85), but not in children. Pooling the studies of adults and children yielded a significantly higher incidence of hyperglycaemia in the rhGH-treated participants (RR 2.65; 95% CI 1.68 to 4.16).

AUTHORS' CONCLUSIONS

There is some evidence that using rhGH in people with large burns (more than 40% of the total body surface area) could result in more rapid healing of the burn wound and donor sites in adults and children, and in reduced length of hospital stay, without increased mortality or scarring, but with an increased risk of hyperglycaemia. This evidence is based on studies with small sample sizes and risk of bias and requires confirmation in higher quality, adequately powered trials.

Burn rehabilitation and research: proceedings of a consensus summit

Burn rehabilitation is an essential component of successful patient care. In May 2008, a group of burn rehabilitation clinicians met to discuss the status and future needs of burn rehabilitation. Fifteen topic areas pertinent to clinical burn rehabilitation were addressed. Consensus positions and suggested future research directions regarding the physical aspects of burn rehabilitation are shared.

Growth hormone (GH): usage and abuse

Growth hormone is essential for body growth but it also modulates metabolic pathways as well as neural, reproductive, immune, cardiovascular, and pulmonary functions. Numerous beneficial effects of growth hormone have led to its expanded therapeutic use in both children and adults. There are several officially approved applications of human growth hormone and many more proposed applications that resulted from huge number of clinical studies on GH therapy. Growth hormone abuse includes improper or excessive use. Over the last decade GH has become one of the most commonly abused drugs in sport due to the fact that its administration is currently undetectable. Enormous doses that are injected and frequent simultaneous abuse of other substances such as other anabolic steroids (testosterone) lead to frequent side effects that may be fatal. In spite of numerous beneficial effects of growth hormone the true physiological impact of GH replacement therapy on various metabolic parameters may be confounded by the dose and route of administration of GH so accurate physicians' monitoring during GH therapy is needed.