Does inhalation injury limit exercise endurance in children convalescing from thermal injury?

Inter-individual variability of aerobic capacity after rehabilitation exercise training in children with severe burn injury

INTRODUCTION

Severe burn trauma damages resting and exercise cardiac function that may affect long term cardiovascular health. The implementation of rehabilitation exercise training (RET) soon after hospital discharge improves cardiorespiratory fitness; however, it does not fully restore aerobic capacity and presents large inter-individual variability. We tested the hypothesis that the inter-individual variability of aerobic capacity for responders (R) compared to nonresponders (NR) would differ for exercise frequency and intensity.

METHODS

Thirty-three children (11 female, [mean±SD] 12 ± 3 years, 145 ± 18 cm, 40 ± 11 kg, 49 ± 31 BMI percentile) with severe burns (49 ± 15 % total body surface area burned, with 35 ± 22 % third-degree burns) completed a 6-week RET program. Cardiorespiratory fitness (peak VO2) was measured before and after RET. Frequency (session days/week), intensity (% peak heart rate), time (min/session), and volume (min/week) were compared between responders and non-responders. Significance was set at p < 0.05.

RESULTS

Sixty-four percent of the study population improved peak VO2 after RET whereas 36 % showed no improvements. Using a 2-way factorial ANOVA (group [G] × week [WK]), we found that exercise frequency and session time were similar and increased slightly over 6 weeks between R and NR (main effect for WK; P < 0.002). Exercise volume was significantly lower on week 2 for NR compared to R (G × WK interaction, P < 0.028). Exercise intensity over 6-weeks was significantly lower in the NR compared to the R group (G × WK interaction, P < 0.022).

CONCLUSIONS

Exercise intensity and volume may be important contributors for improving the interindividual response to exercise training for peak VO2. These data suggest that the appropriate dose-response requirement for exercise intensity may be > 80 % peak heart rate and exercise volume of > 150 min per week. Further understanding of the exercise prescription will provide insights important for cardiovascular rehabilitation in children with severe burns.

SUBJECT CODE

Inter-individual Variability, Exercise, Pediatrics, Exercise Training.

Adults with well-healed burn injuries have lower pulmonary function values decades after injury

Sub-acute (e.g., inhalation injury) and/or acute insults sustained during a severe burn injury impairs pulmonary function. However, previous work has not fully characterized pulmonary function in adults with well-healed burn injuries decades after an injury. Therefore, we tested the hypothesis that adults with well-healed burn injuries have lower pulmonary function years after recovery. Our cohort of adults with well-healed burn-injuries (n = 41) had a lower forced expiratory volume in one second (Burn: 93 ± 16 vs. Control: 103 ± 10%predicted, mean ± SD; d = 0.60, p = 0.04), lower maximal voluntary ventilation (Burn: 84 [71-97] vs. Control: 105 [94-122] %predicted, median [IQR]; d = 0.84, p < 0.01), and a higher specific airway resistance (Burn: 235 ± 80 vs. Control: 179 ± 40%predicted, mean ± SD; d = 0.66, p = 0.02) than non-burned control participants (n = 12). No variables were meaningfully influenced by having a previous inhalation injury (d ≤ 0.44, p ≥ 0.19; 13 of 41 had an inhalation injury), the size of the body surface area burned (R2  ≤ 0.06, p ≥ 0.15; range of 15%-88% body surface area burned), or the time since the burn injury (R2  ≤ 0.04, p ≥ 0.22; range of 2-50 years post-injury). These data suggest that adults with well-healed burn injuries have lower pulmonary function decades after injury. Therefore, future research should examine rehabilitation strategies that could improve pulmonary function among adults with well-healed burn injuries.

Optimization of pulmonary function, functional capacity, and quality of life in adolescents with thoracic burns after a 2-month arm cycling exercise programme: A randomized controlled study

BACKGROUND

Burns to the thorax are at high risk for long-term pulmonary complications due to chest muscle contractures and chronic inflammation in both adolescents and young adults. Few studies have investigated the effects of arm cycling exercise in those individuals. For that reason, this study examined pulmonary function, functional capacity, and quality of life (QOL) in adolescents with thoracic burns subsequent to 2-month arm cycling exercise programme.

METHODS

A single-blinded, two-month randomized prospective controlled study was carried out between July 2019 and March 2020 on thirty adolescents with chest burns aged 11-17 years. They were randomized into two equal groups (n = 15), traditional physiotherapy programme (control group), and arm cycling exercise plus traditonal physiotherapy (arm cycling exercise group) for 2 consecutive months. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), six-minute walk test (6MWT), and Pediatric Quality of Life Inventory (PedsQL) were measured in both groups at baseline and after 2-month after intervention.

RESULTS

No statistical significance was detected at baseline between control and arm cycling exercise groups (FVC, p = 0.903, FEV1, p = 0.835, 6MWT, p = 0.817, and PedsQL, p = 0.612). 2 months after intervention showed statistical improvements in the arm cycling exercise group in all measures (FVC, p = 0.001, FEV1, p < 0.0001, 6MWT, p = 0.001, and PedsQL, p = 0.001) however, the control group showed statistical improvements in FVC, p = 0.044 and FEV1, p = 0.024 with non-statistically significant changes in 6MWT, p = 0.145 and PedsQL, p = 0.067. The arm cycling exercise group showed greater improvements than control group in the outcome measures (FVC, p = 0.034, FEV1, p < 0.017, 6MWT, p = 0.037, and PedsQL, p = 0.021).

CONCLUSIONS

This prospective study clearly demonstrated positive and beneficial influences of two-month arm cycling exercise in the optimization of pulmonary functions, functional performance, and QOL in adolescents suffering from chest burns and thereby eliminating post-burn complications.

Beyond the acute phase: understanding relationships among cardio-respiratory response to exercises, physical activity levels, and quality of life in children after burn injuries

The long-term cardiorespiratory function in burn-injured children can be jeopardized due to complications brought on by the injury. This study sought to assess the cardio-respiratory responses to maximal exercise in children who sustained a burn injury and explore the relationships among cardio-respiratory response, physical activity levels (PALs), and health-related quality of life (HRQL). Forty-five burn-injured children (age:13.89±2.43 years; duration since burn-injury: 3.13±0.93 years) and 52 age- and gender-matched healthy children (14.15±2.27 years) participated in this study. Both cohorts were evaluated for the maximal exercise capacity [defined by peak oxygen uptake (VO2peak), maximum heart rate (HRmax), minute ventilation (VE), ventilatory equivalent (VEq), respiratory rate (RR), and respiratory exchange ratio (RER)], PALs, and HRQL. The burn-injured children had significantly lower VO2peak (P=.0001) and VE (P=.003) and higher VEq (P<.0001) and RR (P=.007) than their healthy controls, indicating less efficient cardio-respiratory capacity. However, the HRmax (P=.092) and RER (P=.251) were similar. The burn-injured children reported significantly lower PALs (P=.014) and HRQL (P<.0001). The PALs [r (95%CI) = 0.411 (0.132 to 0.624); P = .005] and HRQL [r (95%CI) = 0.536 (0.284 to 0.712); P = .0001] were significantly correlated with the cardio-respiratory capacity represented by VO2peak in burn-injured group. The variations in VO2peak explained ⁓ 17% and 28.7% of the variations in PALs and HRQL, respectively. In conclusion, the cardio-respiratory efficiency of the burn-injured children may remain limited, even up to a few years following the injury. The limited cardio-respiratory capacity account in part for the reduced PALs and HRQL.

The effects of resistance training on children with burns: a meta-analysis

The aim of this study was to evaluate effectiveness and safety of resistance training (RT). Data were retrieved from Medline, EMBASE, PubMed, CINAHL and Cochrane Central Register of Controlled Trials (Central) databases from inception to April 2020. Quantitative studies on RT for muscle strength, lean body mass, cardiopulmonary function, metabolism, quality of life, and pain in burned children were included in this study. Twelve RCTs (379 patients) were identified. Meta-analysis showed RT significant increase in muscle strength [SMD = 2.18, 95% CI (0.79, 3.56), p = 0.002]. However, training showed no significant effect on muscle endurance [MD = 10.00, 95% CI (- 0.22, 20.22), p = 0.06]. Notably, training significantly increases total lean body mass [MD = 2.10, 95% CI (1.28, 2.92), p < 0.001]. In addition, training significantly increased leg lean body mass [MD = 2.10, 95% CI (1.28, 2.92), p < 0.001]. Moreover, training significantly increased VO₂peak [MD = 5.83, 95% CI (3.52, 8.13), p < 0.001]. Meta-analysis showed that training significantly increases gait parameters, including stride length, step length, velocity and cadence. Furthermore, training significantly increased explosive capacity of lower limb muscles (p < 0.001). Meta-analysis of 6-min walking test results showed that training significantly improves walking speed (p = 0.0008). Notably, all studies showed unclear or high risk of bias; whereas, quality of the evidence was moderate or low. Analysis showed that RT significantly improves clinical outcomes. However, more high-quality, double-blind, randomized control trials should be performed to explore the effects of RT to ensure successful implementation in rehabilitation.

Cardiovascular Effect of Varying Interval Training Frequency in Rehabilitation of Severely Burned Children

Structured exercise programs initiated after acute hospitalization can improve muscle strength and mass, cardiorespiratory capacity, and quality of life in severely burned children. In this retrospective study, we compared the cardiovascular effects of an exercise program incorporating a large number of interval training sessions with a traditional exercise program incorporating a small number of interval training sessions. Severely burned children who completed a large number of sessions (at least three sessions per week, N = 40) were matched to those completing a small number of sessions (a maximum of two sessions per week, N = 40). Maximal oxygen consumption (VO2 max) was measured via the modified Bruce treadmill protocol at discharge, on completion of the exercise program, and at follow-up visits at 6, 12, and 24 months postburn. Both groups were comparable in age (large 13.5 ± 3.0 years vs small 13.1 ± 3.3 years) and percent total BSA burned (large 50.8 ± 14.8% vs small 49.2 ± 13.3%). For both groups, VO2 max increased from discharge (large 22.6 ± 3.8 ml/kg/min; small 22.6 ± 5.0 ml/kg/min) to postexercise (large 29.5 ± 6.0 ml/kg/min; small 28.0 ± 5.8 ml/kg/min), 6 months (large 33.2 ± 5.9 ml/kg/min; small 29.6 ± 7.0 ml/kg/min), 12 months (large 35.0 ± 7.5 ml/kg/min; small 31.7 ± 7.1 ml/kg/min), and 24 months (large 37.0 ± 7.2 ml/kg/min; small 32.4 ± 9.2 ml/kg/min, P < .001). VO2 increased to a greater extent with a large number of interval sessions than with a small number at 6 and 24 months (both P = .021). These findings suggest that a large number of interval training sessions impart a greater benefit on cardiorespiratory fitness than a small number of sessions.

Resting β-Adrenergic Blockade Does Not Alter Exercise Thermoregulation in Children With Burn Injury: A Randomized Control Trial

The objective of this study was to test the hypothesis that propranolol, a commonly prescribed β-blocker to burned children, in combination with exercise-heat stress, increases the risk of heat illness and exercise intolerance. In a randomized double-blind study, propranolol was given to 10 burned children, and placebo was given to 10 additional burned children (matched for TBSA burned; mean ± SD, 62 ± 13%), while nonburned children served as healthy controls. All groups were matched for age and body morphology (11.2 ± 3.0 years; 146 ± 19 cm; 45 ± 18 kg; 1.3 ± 0.4 m2). All children exercised in hot conditions (34.3 ± 1.0°C; 26 ± 2% relative humidity) at 75% of their peak aerobic capacity. At the end of exercise, none of the groups differed for final or change from baseline intestinal temperature (38.0 ± 0.5°C; 0.02 ± 0.01Δ°C·min-1), unburned (37.0 ± 0.6°C) and burned skin temperatures (36.9 ± 0.7°C; nonburn group excluded), heat loss (21 ± 18 W m-2), whole-body thermal conductance (118 ± 113 W m-2), or physiological strain index (5.6 ± 1). However, burn children exercised less than nonburn group (21.2 ± 8.6 vs 30 ± 0.0 min; P < .001) and had a lower calculated exercise tolerance index (1.0 ± 0.0 vs 6.7 ± 4.3; P < .01). Burned children had lower peak heart rates than nonburned children (173 ± 13 vs 189 ± 7 bpm; P < .01), with greater relative cardiac work rates at the end of exercise (97 ± 10 vs 85 ± 11% peak heart rate; P < .01). Resting β-adrenergic blockade does not affect internal body temperature of burned children exercising at similar relative intensities as nonburn children in the heat. Independent of propranolol, a suppressed cardiac function may be associated to exercise intolerance in children with severe burn injury.

Estimated versus achieved maximal oxygen consumption in severely burned children maximal oxygen consumption in burned children

PURPOSE

In burned children, exercise training increases maximal oxygen consumption (VO2 max) and can be combined with the nonspecific beta-blocker propranolol to decrease cardiac work. VO2 max is estimated if indirect calorimetry is not available. We compared measured and estimated VO2 max in severely burned children treated with or without propranolol to determine the suitability of commonly used formulas in these populations.

METHODS

Patients received propranolol or placebo (control) during acute hospitalization. VO2 max was measured during a modified Bruce treadmill test at discharge and compared to values obtained using the Cooper, Bruce, American College of Sports Medicine, and Porro formulas. Pearson correlations and Bland-Altman analyses were used to compare measured and estimated values.

RESULTS

Ninety-nine children (propranolol n=46,control n=53) admitted at our facility between 2003 and 2016 were analyzed. Age at burn (propranolol 12±4years, control 12±3years,p=0.893) and total body surface area burned (propranolol 44±15%,control 49±14%,p=0.090) were comparable between groups. Measured VO2 max was higher in the propranolol group (25.5±6.0mL/min/kg vs. 22.0±4.7mL/min/kg,p=0.002) and was generally lower than estimated values. Age, sex, inhalation injury, body mass index, exercise time, and maximal speed were predictive of measured VO2 max in the control group. Age, sex, and maximal speed were predictive in the propranolol group. Backward selection yielded the formula [7.63+ 2.16×sex(females=0,males=1)+0.41×age(years)+0.15×maximal speed(m/min)] (R2=0.6525).

CONCLUSIONS

Propranolol seems to have beneficial effects on cardiorespiratory capacity in burned children. However, estimated VO2 max with common formulas were too high. The VO2 max formula reported here is suitable for propranolol-treated children and the Porro formula for non-propranolol-treated children.

Children with Burn Injury Have Impaired Cardiac Output during Submaximal Exercise

INTRODUCTION

Burn trauma damages resting cardiac function; however, it is currently unknown if the cardiovascular response to exercise is likewise impaired. We tested the hypothesis that, in children, burn injury lowers cardiac output (Q˙) and stroke volume (SV) during submaximal exercise.

METHODS

Five children with 49% ± 4% total body surface area (BSA) burned (two female, 11.7 ± 1 yr, 40.4 ± 18 kg, 141.1 ± 9 cm) and eight similar nonburned controls (five female, 12.5 ± 2 yr, 58.0 ± 17 kg, 147.3 ± 12 cm) with comparable exercise capacity (peak oxygen consumption [peak V˙O2]: 31.9 ± 11 vs 36.8 ± 8 mL O2·kg·min, P = 0.39) participated. The exercise protocol entailed a preexercise (pre-EX) rest period followed by 3-min exercise stages at 20 W and 50 W. V˙O2, HR, Q˙ (via nonrebreathing), SV (Q˙/HR), and arteriovenous O2 difference ([a-v]O2diff, Q˙/ V˙O2) were the primary outcome variables.

RESULTS

Using a 2-way factorial ANOVA (group [G] × exercise [EX]), we found that Q˙ was approximately 27% lower in the burned than the nonburned group at 20 W of exercise (burned 5.7 ± 1.0 vs nonburned: 7.9 ± 1.8 L·min) and 50 W of exercise (burned 6.9 ± 1.6 vs nonburned 9.2 ± 3.2 L·min) (G-EX interaction, P = 0.012). SV did not change from rest to exercise in burned children but increased by approximately 24% in the nonburned group (main effect for EX, P = 0.046). Neither [a-v] O2diff nor V˙O2 differed between groups at rest or exercise, but HR response to exercise was reduced in the burn group (G-EX interaction, P = 0.004). When normalized to BSA, SV (index) was similar between groups; however, Q˙ (index) remained attenuated in the burned group (G-EX interaction, P < 0.008).

CONCLUSIONS

Burned children have an attenuated cardiovascular response to submaximal exercise. Further investigation of hemodynamic function during exercise will provide insights important for cardiovascular rehabilitation in burned children.

The role of exercise in the rehabilitation of patients with severe burns

Severe burn trauma results in persistent skeletal muscle catabolism and prolonged immobilization. We hypothesize that structured rehabilitative exercise is a safe and efficacious strategy to restore lean body mass and physical function in burn victims. Here, we review the evidence for the utility of rehabilitative exercise training in restoring physiological function in burn survivors.

Burn intensive care

As a result of continuous development in the treatment of burns, the LD50 (the burn size lethal to 50% of the population) for thermal injuries has risen from 42% total body surface area (TBSA) during the 1940s and 1950s to more than 90% TBSA for young thermally injured patients. This vast improvement in survival is due to simultaneous developments in critical care, advancements in resuscitation, control of infection through early excision, and pharmacologic support of the hypermetabolic response to burns. This article reviews these recent advances and how they influence modern intensive care of burns.

Development of a long-term ovine model of cutaneous burn and smoke inhalation injury and the effects of early excision and skin autografting

Smoke inhalation injury frequently increases the risk of pneumonia and mortality in burn patients. The pathophysiology of acute lung injury secondary to burn and smoke inhalation is well studied, but long-term pulmonary function, especially the process of lung tissue healing following burn and smoke inhalation, has not been fully investigated. By contrast, early burn excision has become the standard of care in the management of major burn injury. While many clinical studies and small-animal experiments support the concept of early burn wound excision, and show improved survival and infectious outcomes, we have developed a new chronic ovine model of burn and smoke inhalation injury with early excision and skin grafting that can be used to investigate lung pathophysiology over a period of 3 weeks.

MATERIALS AND METHODS

Eighteen female sheep were surgically prepared for this study under isoflurane anesthesia. The animals were divided into three groups: an Early Excision group (20% TBSA, third-degree cutaneous burn and 36 breaths of cotton smoke followed by early excision and skin autografting at 24h after injury, n=6), a Control group (20% TBSA, third-degree cutaneous burn and 36 breaths of cotton smoke without early excision, n=6) and a Sham group (no injury, no early excision, n=6). After induced injury, all sheep were placed on a ventilator and fluid-resuscitated with Lactated Ringers solution (4 mL/% TBS/kg). At 24h post-injury, early excision was carried out to fascia, and skin grafting with meshed autografts (20/1000 in., 1:4 ratio) was performed under isoflurane anesthesia. At 48 h post-injury, weaning from ventilator was begun if PaO(2)/FiO(2) was above 250 and sheep were monitored for 3 weeks.

RESULTS

At 96 h post-injury, all animals were weaned from ventilator. There are no significant differences in PaO(2)/FiO(2) between Early Excision and Control groups at any points. All animals were survived for 3 weeks without infectious complication in Early Excision and Sham groups, whereas two out of six animals in the Control group had abscess in lung. The percentage of the wound healed surviving area (mean ± SD) was 74.7 ± 7.8% on 17 days post-surgery in the Early Excision group. Lung wet-to-dry weight ratio (mean ± SD) was significantly increased in the Early Excision group vs. Sham group (p<0.05). The calculated net fluid balance significantly increased in the early excision compared to those seen in the Sham and Control groups. Plasma protein, oncotic pressure, hematocrit of % baseline, hemoglobin of % baseline, white blood cell and neutrophil were significantly decreased in the Early Excision group vs. Control group.

CONCLUSIONS

The early excision model closely resembles practice in a clinical setting and allows long-term observations of pulmonary function following burn and smoke inhalation injury. Further studies are warranted to assess lung tissue scarring and measuring collagen deposition, lung compliance and diffusion capacity.

Prediction of maximal aerobic capacity in severely burned children

INTRODUCTION

Maximal oxygen uptake (VO₂ peak) is an indicator of cardiorespiratory fitness, but requires expensive equipment and a relatively high technical skill level.

PURPOSE

The aim of this study is to provide a formula for estimating VO₂ peak in burned children, using information obtained without expensive equipment.

METHODS

Children, with ≥ 40% total surface area burned (TBSA), underwent a modified Bruce treadmill test to assess VO(2) peak at 6 months after injury. We recorded gender, age, %TBSA, %3rd degree burn, height, weight, treadmill time, maximal speed, maximal grade, and peak heart rate, and applied McHenry's select algorithm to extract important independent variables and Robust multiple regression to establish prediction equations.

RESULTS

42 children; 7-17 years old were tested. Robust multiple regression model provided the equation: VO₂ =10.33-0.62 × age (years)+1.88 × treadmill time (min)+2.3 (gender; females = 0, males = 1). The correlation between measured and estimated VO₂ peak was R = 0.80. We then validated the equation with a group of 33 burned children, which yielded a correlation between measured and estimated VO₂ peak of R = 0.79.

CONCLUSIONS

Using only a treadmill and easily gathered information, VO₂ peak can be estimated in children with burns.

Respiratory management of inhalation injury

Advances in the care of patients with major burns have led to a reduction in mortality and a change in the cause of their death. Burn shock, which accounted for almost 20 percent of burn deaths in the 1930s and 1940s, is now treated with early, vigorous fluid resuscitation and is only rarely a cause of death. Burn wound sepsis, which emerged as the primary cause of mortality once burn shock decreased in importance, has been brought under control with the use of topical antibiotics and aggressive surgical debridement. Inhalation injury has now become the most frequent cause of death in burn patients. Although mortality from smoke inhalation alone is low (0-11 percent), smoke inhalation in combination with cutaneous burns is fatal in 30 to 90 percent of patients. It has been recently reported that the presence of inhalation injury increases burn mortality by 20 percent and that inhalation injury predisposes to pneumonia. Pneumonia has been shown to independently increase burn mortality by 40 percent, and the combination of inhalation injury and pneumonia leads to a 60 percent increase in deaths. Children and the elderly are especially prone to pneumonia due to a limited physiologic reserve. It is imperative that a well organized, protocol driven approach to respiratory care of inhalation injury be utilized so that improvements can be made and the morbidity and mortality associated with inhalation injury be reduced.

Burns

During the past 20 yrs, as burn care has evolved as a specialty of surgery, survival and outcome quality have soared. Public expectations for survival and long-term outcomes are at previously unprecedented levels. These changes are the result of a number of advances in aspects of burn care that have occurred in parallel and have fostered increasing regionalization of this resource-intensive activity into fewer specialized centers. These are complex hospitalizations and can be divided into four phases: initial evaluation and resuscitation, initial wound excision and biological closure, definitive wound closure, and rehabilitation and reconstruction.

Effect of exercise training on pulmonary function in children with thermal injury

Severe thermal injury in children results in a decrease in pulmonary function (PF) which lasts well into convalescence. Exercise has been used successfully to improve PF in other populations exhibiting a compromised PF such as in chronic obstructive pulmonary disease. Yet, whether exercise training will induce improvements in PF in burned children is presently unknown. We therefore evaluated if an exercise program improved PF in severely burned children (BC). Twenty healthy controls, nonburn children (NB) age 7 to <18 and 31 severely burned children; ages 7 to <18 years old, with greater than 40% of total body surface area burned were enrolled in the study. Burned children were randomized into two groups. One to participate in a 12-week in-hospital physical rehabilitation program supplemented with an exercise-training program (REX, n = 17) and the other nonexercising group (R, n = 14) to participate in a 12-week, home-based physical rehabilitation program without exercise. Pulmonary function tests were performed for all groups at baseline, but only the REX and R groups were tested after 12 weeks of either exercise or no exercise. Baseline PF for the NB group was normal and no differences in PF were found between the R vs REX groups. However, PF was decreased in BC compared to NB children. There was a significant improvement in PF in the REX group. In contrast, PF in the R group remained relatively unchanged. Severely burned children improve PF as a result of an exercise program and such should be a fundamental component of a multidisciplinary outpatient treatment program for victims of thermal injury.

Lung function following thermal injury in children--an 8-year follow up

INTRODUCTION

despite the frequency of pulmonary complications and the reports of abnormal lung function as a sequela of severe thermal injury, most of the lung function studies following thermal injury have been directed at the immediate post-burn period. This investigation is designed to evaluate late residual respiratory impairment in patients with severe thermal injury.

METHODS

spirometry and lung volumes were completed on 17 children with severe thermal injury 8 years post-injury. None of the patients had pre-existing lung disease prior to injury.

RESULTS

the patient demographic data was as follows: nine male, eight female patients; mean TBSB=67+/-29%; mean third degree=62+/-32%; 13 patients had inhalation injury diagnosed by bronchoscopy. Spirometry and lung volumes at examination as a percentage of predicted values were: [see table in text]. Spirometry and lung volumes show: two patients had an obstructive disease process; nine patients had an obstructive and restrictive disease process; five patients had a purely restrictive process; and one patient had a diffusion defect.

CONCLUSION

the data indicate that children who survive severe thermal injury may not regain normal lung function.