- Email: [email protected]
Rhabdomyolysis caused by hot air sauna burn
Burns 31 (2005) 776–779 www.elsevier.com/locate/burns
Rhabdomyolysis caused by hot air sauna burn Antti Koski, Virve Koljonen *, Jyrki Vuola Department of Plastic Surgery, To¨o¨lo¨ Hospital, Helsinki University Hospital, Finland P.O. Box 266, FIN 00029 HUS, Finland Accepted 24 April 2005
Abstract Sauna-related burns are rare, even in Finland where sauna bathing is a popular leisure pastime. Burns induced by hot air are even more rare and constitute a very small subgroup of all sauna burns. Hot air burns are characterised by a combination of full thickness skin damage with deep tissue destruction. We report here on six consecutive patients suffering from hot air sauna burns with rhabdomyolysis. All six patients were middle-aged, the majority of them men. Acute excessive consumption of alcohol exacerbated by a hot environment resulted in dehydration and loss of consciousness. Immobility and prolonged exposure to hot, dry air resulted in third degree regional burns with 5–32% TBSA. Rhabdomyolysis was evident on admission. The laboratory values of plasma creatine kinase (P-CK), plasma myoglobin (PM), blood pH, and serum potassium (S-K) during the first five days were evaluated. Aggressive fluid management and correction of acidosis and myoglobinuria were started on admission. Surgical management consisted of early, aggressive excision at fascial level, in some patients involving sacrifice of the upper layers of muscle. Even so, mortality in this small series was 50%. The best indicator of poor prognosis was a highly elevated CK value on the second post-injury day. # 2005 Elsevier Ltd and ISBI. All rights reserved. Keywords: Sauna; Burns; Hot air; Rhabdomyolysis
1. Introduction Sauna bathing is a popular recreational activity in Finland and is generally considered safe for pregnant women and those suffering from heart problems [1,2]. As well as being a social event, sauna bathing also has medicinal value. Recent reports have shown the ability of sauna therapy to improve cardiac and vascular endothelial function in patients with congestive heart failure [3,4]. The temperature in the sauna room in those studies was only 60 8C, whereas in the normal Finnish recreational sauna the temperature is usually between 80 and 90 8C, often even above 100 8C. A wide variety of burn injuries, in all age groups, are related to sauna bathing; scalds and contact burns account for over 85% of these burns but hot air, steam and flame burns for only 15% [5,6]. The majority of hospitalised sauna-burn patients were injured while under the influence of alcohol [5]. The mechanism of the hot, dry air burn involves prolonged exposure to the hot air as a result of immobility * Corresponding author. Tel.: +358 50 427 1983; fax: +358 9 471 87 217. E-mail address: [email protected] (V. Koljonen). 0305-4179/$30.00 # 2005 Elsevier Ltd and ISBI. All rights reserved. doi:10.1016/j.burns.2005.04.024
due to loss of consciousness. This results in a complex injury in which full-thickness skin damage occurs concurrently with deeper tissue destruction. A similar pattern is encountered in electrical injuries. In both burn types, the deeper tissue damage leads to rhabdomyolysis. Rhabdomyolysis is caused by disintegration of the striated muscle, and is induced by various factors such as trauma, compression, occlusion or hypoperfusion of muscle vessels and stressful exercise. Rhabdomyolysis may also follow heat stroke. The diagnosis is based on elevated laboratory values of creatine kinase, myoglobin and potassium. We report here the cases of six consecutive patients who suffered hot air sauna burns with potentially fatal rhabdomyolysis.
2. Patients The study comprised six consecutive hot air sauna burn patients treated at the Helsinki Burn Unit, Department of Plastic Surgery at Helsinki University Hospital, during
A. Koski et al. / Burns 31 (2005) 776–779
777
Table 1 Patient and injury characteristics Patient number
Sex/age (years)
Alcohol (%)
TBSA
Position when found
Injured body part
First operation post injury day
1 2 3 4 5 6
M/65 M/75 M/54 F/64 M/38 M/72
2.7 2.0 3.5 1.5 2.2 1.5
27 23 5 18 25 32
Lying on the left side Lying on the right side Dorsal position Lying on the left side Lying supine on the footrest Supine
Right upper extremity, gluteus, abdomen Left upper extremity, thigh, neck Lower abdomen, groins and thighs Right deltoid, brachium, back, thigh Back, posterior thighs Back and gluteal region
1 4 15 2 2 5
1996–2003. The clinical data, and injury and treatment characteristics of these patients were collected from the surgical database. The laboratory values of plasma creatine kinase (P-CK), plasma myoglobin (PM), blood pH and serum potassium (S-K) during the first 5 days in hospital were obtained from the patients’ charts. The detailed characteristics of patients and injuries are presented in Table 1. Five of the patients were men and one was a woman; their mean age was 61 years. All were under the influence of alcohol at the time of injury, their mean serum alcohol level being 2.23 mg/100 ml (1.5–3.5%). The overall time spent in the sauna was 1–3 h. All patients were found unconscious in the sauna after 30 min to 1 h. None had been in contact with the hot stove or showed wounds or bruises in the head indicating an accidental fall. All patients presented with third degree deep burns (Fig. 1). The mean total body surface area (TBSA) was 21.7% (range 5–32%). The injured body parts were those that had been in prolonged contact with hot air, as was verified from the ambulance documents reporting the patient’s original position in the sauna. All patients except one underwent fascial excision and split thickness skin grafting of the burned areas within the first 5 days. The exception was a patient who was operated
2
3 19
Hospital days 2 48 75 30 3 19
on 2 weeks later. After this 2-week wait, only 5% of the wound was deep and needed operation. At a later stage, one patient (number 2) required a pectoralis major flap to cover the exposed humeral joint. All patients required intensive care on admission. Fluid replacement was administered according to the Parkland Formula. Based on our experience of hot air sauna burns, we started forced diuresis and correction of acidosis and myoglobinuria immediately. All patients had rhabdomyolysis on admission. On day one, the mean P-CK was 14430 U/l (range 902–31180 U/l), pH 7.30 (7.27– 7.34), S-K 4.2 (3.8–5.0) mmol/l and PM 27213 ug/l (2127–76140 ug/l). Table 2 presents the CK values of the patients for the first 3 days. None of the patients developed marked acute renal insufficiency and, thus, none needed dialysis. Only 2 patients (numbers 5 and 6) had elevated plasma creatine values, 257 and 222, respectively. Three of the patients (numbers 1, 5 and 6) died during hospitalisation. These patients had the largest burned areas: 27, 25 and 32% TBSA, respectively. Two of them died during the first 3 post injury days. The third patient suffered a large left-sided cerebellar infarction, diagnosed after serial CT scans, and his treatment was ceased. One patient developed left-sided hemiplegia, which was not diagnosed until several weeks after the injury. He eventually recovered after rehabilitation.
Table 2 P-CK values for the first 3 post injury days
Fig. 1. Patients suffered from regional burns, the burned areas were on the parts of the body that were directly exposed to hot air. Patient was found lying on her left side in the hot steam room.
Exitus post injury day
*
Died during hospitalisation.
778
A. Koski et al. / Burns 31 (2005) 776–779
3. Discussion In this report, we document the occurrence of six hot airinduced sauna burns with potentially fatal rhabdomyolysis. To the best of our knowledge, this is the first report of severe rhabdomyolysis following hot air-induced burns. Sauna-related burns account for approximately 21.5% of all our Burn Unit admissions annually (unpublished observation), a percentage that is consistent with Papp’s observation at the Kuopio Burn Centre [5]. Sauna-related burns include several different types of burn injury: scalds, contact, hot steam, electrical, flame and hot air burns. Direct contact with the stove is by far the most common cause of burns in the sauna, hot air as such being responsible for only a small minority of burns. Hot air burns have a very different injury profile from the more conventional burn injuries, as they combine full thickness skin damage with deep tissue destruction unpredictable in depth. Thus, they tend to resemble an electrical injury. To¨ o¨ lo¨ Hospital is part of Helsinki University Hospital. As the leading trauma centre in southern Finland, it serves the Helsinki and Uusimaa region, with a total of 1.7 million inhabitants, which is more than one-quarter of the population of Finland. During 1996–2002, 34 persons died of hyperthermia in the sauna in the Helsinki and Uusimaa region (Anu Kentta¨ mies, personal communication). The annual number of deaths ranged from two to nine. In an earlier report, Kortelainen et al. discussed hyperthermia deaths in Finland between 1970 and 1986 [7]. The authors found, as we did, that the majority of the victims were middle-aged men. Acute and, in some cases, chronic alcohol consumption was noted in most of the victims. Their autopsy findings suggested that, in addition to the acute hazardous effect of ethanol on thermoregulatory mechanisms, the longterm consumption of alcohol may have promoted fatal hyperthermia in these victims [7]. Alcohol consumption together with sauna bathing may increase the arrhythmia risk because the heat of the sauna enhances adrenergic activity [8]. However, Roine et al. did not find that sauna bathing together with alcohol consumption increased cardiac arrhythmias in healthy young male volunteers [9]. The total time spent in the sauna was between 1 and 3 h, which is normal among Finnish sauna bathers. Not all this time is spent in the steam room, however, as bathers usually take short rests and have a shower or relax outdoors in between. The cycle is typically repeated four to five times. The patients discussed here had been bathing in the company of friends or wives but had then been left alone in the sauna and were found unconscious 30 min to 1 h later. During this relatively short time, they had lost consciousness and been exposed to hot dry air. All the patients in this series suffered from deep tissue burns. The burned areas were on the parts of the body that were directly exposed to hot air; none was in contact with the hot stove. The necrotic area extended to subcutaneous fat tissue and even to the underlying muscles. All patients
underwent an operation whereby the necrotic areas were excised and covered with autologous split thickness skin grafts. The level of excision was typically fascial and, in some areas, layers of the muscle were removed. Our experience shows that affected areas may be unexpectedly badly burned in a layered fashion: there may be some blood circulation in the dermis but the fat and even the muscles underneath are devitalised probably due to slow and long exposure to hot air. Thorough debridement to the well vascularised tissue provided a good wound bed, and good graft intake was noted at follow-up. Contrary to Morris and Rai’s observation, the graft donor areas were normal [10], possibly because our patients had suffered local burns and their position after falling was such that the opposite body parts were not injured. Only one patient required flap reconstruction. He had received a deep burn in his deltoid area and after necrectomy the humeral joint became exposed. This was subsequently covered with a pediculed pectoralis muscle flap. Alcohol consumption results in minor accidents, such as sprains, in the sauna [8]. None of the patients in our series, however, had any wounds or bruises suggesting that they had slipped on the moist sauna floor. All the patients were acutely under the influence of alcohol, the majority quite heavily, with serum alcohol levels ranging from 1.5 to 3.5 mg/100 ml. Moreover, signs of chronic alcohol consumption were noted both in the patients themselves and in their records. Excessive consumption of alcohol together with a hot environment may result in dehydration and eventual loss of consciousness. As a clinical observation, patients with alcohol abuse may require more fluid resuscitation than normal [11]. Dehydration in patients under the influence of alcohol amplifies the risk of hypotension, ethanol as such acting as a diuretic [12]. The risk of hypotension is exacerbated when sauna bathing is combined with alcohol consumption [1,9]. Two patients were diagnosed with brain insults, which became evident at a later stage. One of them suffered massive cerebellar infarction and the other presented with left hemiplegia symptoms. At the same time, these patients were under the influence of alcohol. Neurological examinations were not conducted immediately, because on admission the patients were sedated and intubated. Radiological examinations (CT scans) may therefore be necessary to diagnose the underlying conditions of unconsciousness. The PM and P-CK values of our patients were elevated by several hundred times compared with normal values. The CK value on the second post injury day appears to be the best indicator of prognosis. This finding is supported by Kopp et al., who noted a relation between strongly elevated P-CK levels and mortality in patients with electrical burns [13]. In our series, the P-CK values of the three patients who died were highest on day 2, Table 2. The P-CK level can also be elevated by other events such as pulmonary embolus, stroke, hypothyroidism and intoxication. One of the patients who died (number 6) suffered a large cerebellar infarction in
A. Koski et al. / Burns 31 (2005) 776–779
addition to a burn of 32% TBSA, which was the most extensive burned area in our series. Highly elevated P-CK values are an indicator for the extent and severity of injury. Mortality was 50% in our small series. Rhabdomyolysis associated with burn results in a higher mortality rate than would be expected from the percentage TBSA. A connection between highly elevated PCK values and percentage TBSA was noted. All three diseased patients had the largest burned areas and their P-CK values were highest on day 2, although our patient series was too small to permit an exact numerical value to be deduced for P-CK for prognosis. In conclusion, hot air-induced sauna burns are a rare but potentially fatal injury with subsequent rhabdomyolysis. Alcohol consumption has many harmful effects on the body’s homeostasis such as intervening thermoregulatory mechanisms, causing dehydration and lack of judgement. Considering the potentially dangerous environment, the hot sauna, in which the burns occur it is surprising that these injuries are so rare, even in Finland. Our survey showed that excessive consumption of alcohol is not always the reason for the loss of consciousness. Further radiological and neurological examinations may reveal the underlying factor. In such injuries, mortality exceeds the rate that would be expected from the percentage TBSA. The best prognostic marker for survival was the PCK value on the second post injury day. P-CK values seem to be linked to the severity and extent of the injury. Hot airinduced sauna burns require multidisciplinary expertise to deal with multi-organ dysfunctions and wound care and to plan the timing and strategy of the surgical care.
4. Conflicts of Interest There was no conflict of interest.
779
Acknowledgement The authors thank Dr. Anu Kentta¨ mies, provincial medical examiner for providing the data on hyperthermia deaths in Helsinki and Uusimaa region.
References [1] Hannuksela ML, Ellahham S. Benefits and risks of sauna bathing. Am J Med 2001;110(2):118–26. [2] Kauppinen K. Facts fables about sauna. Ann N Y Acad Sci 1997;813:654–62. [3] Biro S, Masuda A, Kihara T, Tei C. Clinical implications of thermal therapy in lifestyle-related diseases. Exp Biol Med (Maywood) 2003;228(10):1245–9. [4] Kihara T, Biro S, Imamura M, Yoshifuku S, Takasaki K, Ikeda Y, et al. Repeated sauna treatment improves vascular endothelial and cardiac function in patients with chronic heart failure. J Am Coll Cardiol 2002;39(5):754–9. [5] Papp A. Sauna-related burns: a review of 154 cases treated in Kuopio University Hospital Burn Center 1994–2000. Burns 2002;28(1): 57–9. [6] Zeitlin R, Somppi E, Jarnberg J. Paediatric burns in central Finland between the 1960s and the 1980s. Burns 1993;19(5):418–22. [7] Kortelainen ML. Hyperthermia deaths in Finland in 1970–86. Am J Forensic Med Pathol 1991;12(2):115–8. [8] Ylikahri R, Heikkonen E, Soukas A. The sauna and alcohol. Ann Clin Res 1988;20(4):287–91. [9] Roine R, Luurila OJ, Suokas A, Heikkonen E, Koskinen P, Ylikahri R, et al. Alcohol and sauna bathing: effects on cardiac rhythm, blood pressure, and serum electrolyte and cortisol concentrations. J Intern Med 1992;231(4):333–8. [10] Morris AM, Rai S. Sauna bath burn. Br Med J 1978;1(6117):894–5. [11] Yowler CJ, Fratianne RB. Current status of burn resuscitation. Clin Plast Surg 2000;27(1):1–10. [12] Stookey JD. The diuretic effects of alcohol and caffeine and total water intake misclassification. Eur J Epidemiol 1999;15(2):181–8. [13] Kopp J, Loos B, Spilker G, Horch RE. Correlation between serum creatinine kinase levels and extent of muscle damage in electrical burns. Burns 2004;30(7):680–3.
Rhabdomyolysis caused by hot air sauna burn Antti Koski, Virve Koljonen *, Jyrki Vuola Department of Plastic Surgery, To¨o¨lo¨ Hospital, Helsinki University Hospital, Finland P.O. Box 266, FIN 00029 HUS, Finland Accepted 24 April 2005
Abstract Sauna-related burns are rare, even in Finland where sauna bathing is a popular leisure pastime. Burns induced by hot air are even more rare and constitute a very small subgroup of all sauna burns. Hot air burns are characterised by a combination of full thickness skin damage with deep tissue destruction. We report here on six consecutive patients suffering from hot air sauna burns with rhabdomyolysis. All six patients were middle-aged, the majority of them men. Acute excessive consumption of alcohol exacerbated by a hot environment resulted in dehydration and loss of consciousness. Immobility and prolonged exposure to hot, dry air resulted in third degree regional burns with 5–32% TBSA. Rhabdomyolysis was evident on admission. The laboratory values of plasma creatine kinase (P-CK), plasma myoglobin (PM), blood pH, and serum potassium (S-K) during the first five days were evaluated. Aggressive fluid management and correction of acidosis and myoglobinuria were started on admission. Surgical management consisted of early, aggressive excision at fascial level, in some patients involving sacrifice of the upper layers of muscle. Even so, mortality in this small series was 50%. The best indicator of poor prognosis was a highly elevated CK value on the second post-injury day. # 2005 Elsevier Ltd and ISBI. All rights reserved. Keywords: Sauna; Burns; Hot air; Rhabdomyolysis
1. Introduction Sauna bathing is a popular recreational activity in Finland and is generally considered safe for pregnant women and those suffering from heart problems [1,2]. As well as being a social event, sauna bathing also has medicinal value. Recent reports have shown the ability of sauna therapy to improve cardiac and vascular endothelial function in patients with congestive heart failure [3,4]. The temperature in the sauna room in those studies was only 60 8C, whereas in the normal Finnish recreational sauna the temperature is usually between 80 and 90 8C, often even above 100 8C. A wide variety of burn injuries, in all age groups, are related to sauna bathing; scalds and contact burns account for over 85% of these burns but hot air, steam and flame burns for only 15% [5,6]. The majority of hospitalised sauna-burn patients were injured while under the influence of alcohol [5]. The mechanism of the hot, dry air burn involves prolonged exposure to the hot air as a result of immobility * Corresponding author. Tel.: +358 50 427 1983; fax: +358 9 471 87 217. E-mail address: [email protected] (V. Koljonen). 0305-4179/$30.00 # 2005 Elsevier Ltd and ISBI. All rights reserved. doi:10.1016/j.burns.2005.04.024
due to loss of consciousness. This results in a complex injury in which full-thickness skin damage occurs concurrently with deeper tissue destruction. A similar pattern is encountered in electrical injuries. In both burn types, the deeper tissue damage leads to rhabdomyolysis. Rhabdomyolysis is caused by disintegration of the striated muscle, and is induced by various factors such as trauma, compression, occlusion or hypoperfusion of muscle vessels and stressful exercise. Rhabdomyolysis may also follow heat stroke. The diagnosis is based on elevated laboratory values of creatine kinase, myoglobin and potassium. We report here the cases of six consecutive patients who suffered hot air sauna burns with potentially fatal rhabdomyolysis.
2. Patients The study comprised six consecutive hot air sauna burn patients treated at the Helsinki Burn Unit, Department of Plastic Surgery at Helsinki University Hospital, during
A. Koski et al. / Burns 31 (2005) 776–779
777
Table 1 Patient and injury characteristics Patient number
Sex/age (years)
Alcohol (%)
TBSA
Position when found
Injured body part
First operation post injury day
1 2 3 4 5 6
M/65 M/75 M/54 F/64 M/38 M/72
2.7 2.0 3.5 1.5 2.2 1.5
27 23 5 18 25 32
Lying on the left side Lying on the right side Dorsal position Lying on the left side Lying supine on the footrest Supine
Right upper extremity, gluteus, abdomen Left upper extremity, thigh, neck Lower abdomen, groins and thighs Right deltoid, brachium, back, thigh Back, posterior thighs Back and gluteal region
1 4 15 2 2 5
1996–2003. The clinical data, and injury and treatment characteristics of these patients were collected from the surgical database. The laboratory values of plasma creatine kinase (P-CK), plasma myoglobin (PM), blood pH and serum potassium (S-K) during the first 5 days in hospital were obtained from the patients’ charts. The detailed characteristics of patients and injuries are presented in Table 1. Five of the patients were men and one was a woman; their mean age was 61 years. All were under the influence of alcohol at the time of injury, their mean serum alcohol level being 2.23 mg/100 ml (1.5–3.5%). The overall time spent in the sauna was 1–3 h. All patients were found unconscious in the sauna after 30 min to 1 h. None had been in contact with the hot stove or showed wounds or bruises in the head indicating an accidental fall. All patients presented with third degree deep burns (Fig. 1). The mean total body surface area (TBSA) was 21.7% (range 5–32%). The injured body parts were those that had been in prolonged contact with hot air, as was verified from the ambulance documents reporting the patient’s original position in the sauna. All patients except one underwent fascial excision and split thickness skin grafting of the burned areas within the first 5 days. The exception was a patient who was operated
2
3 19
Hospital days 2 48 75 30 3 19
on 2 weeks later. After this 2-week wait, only 5% of the wound was deep and needed operation. At a later stage, one patient (number 2) required a pectoralis major flap to cover the exposed humeral joint. All patients required intensive care on admission. Fluid replacement was administered according to the Parkland Formula. Based on our experience of hot air sauna burns, we started forced diuresis and correction of acidosis and myoglobinuria immediately. All patients had rhabdomyolysis on admission. On day one, the mean P-CK was 14430 U/l (range 902–31180 U/l), pH 7.30 (7.27– 7.34), S-K 4.2 (3.8–5.0) mmol/l and PM 27213 ug/l (2127–76140 ug/l). Table 2 presents the CK values of the patients for the first 3 days. None of the patients developed marked acute renal insufficiency and, thus, none needed dialysis. Only 2 patients (numbers 5 and 6) had elevated plasma creatine values, 257 and 222, respectively. Three of the patients (numbers 1, 5 and 6) died during hospitalisation. These patients had the largest burned areas: 27, 25 and 32% TBSA, respectively. Two of them died during the first 3 post injury days. The third patient suffered a large left-sided cerebellar infarction, diagnosed after serial CT scans, and his treatment was ceased. One patient developed left-sided hemiplegia, which was not diagnosed until several weeks after the injury. He eventually recovered after rehabilitation.
Table 2 P-CK values for the first 3 post injury days
Fig. 1. Patients suffered from regional burns, the burned areas were on the parts of the body that were directly exposed to hot air. Patient was found lying on her left side in the hot steam room.
Exitus post injury day
*
Died during hospitalisation.
778
A. Koski et al. / Burns 31 (2005) 776–779
3. Discussion In this report, we document the occurrence of six hot airinduced sauna burns with potentially fatal rhabdomyolysis. To the best of our knowledge, this is the first report of severe rhabdomyolysis following hot air-induced burns. Sauna-related burns account for approximately 21.5% of all our Burn Unit admissions annually (unpublished observation), a percentage that is consistent with Papp’s observation at the Kuopio Burn Centre [5]. Sauna-related burns include several different types of burn injury: scalds, contact, hot steam, electrical, flame and hot air burns. Direct contact with the stove is by far the most common cause of burns in the sauna, hot air as such being responsible for only a small minority of burns. Hot air burns have a very different injury profile from the more conventional burn injuries, as they combine full thickness skin damage with deep tissue destruction unpredictable in depth. Thus, they tend to resemble an electrical injury. To¨ o¨ lo¨ Hospital is part of Helsinki University Hospital. As the leading trauma centre in southern Finland, it serves the Helsinki and Uusimaa region, with a total of 1.7 million inhabitants, which is more than one-quarter of the population of Finland. During 1996–2002, 34 persons died of hyperthermia in the sauna in the Helsinki and Uusimaa region (Anu Kentta¨ mies, personal communication). The annual number of deaths ranged from two to nine. In an earlier report, Kortelainen et al. discussed hyperthermia deaths in Finland between 1970 and 1986 [7]. The authors found, as we did, that the majority of the victims were middle-aged men. Acute and, in some cases, chronic alcohol consumption was noted in most of the victims. Their autopsy findings suggested that, in addition to the acute hazardous effect of ethanol on thermoregulatory mechanisms, the longterm consumption of alcohol may have promoted fatal hyperthermia in these victims [7]. Alcohol consumption together with sauna bathing may increase the arrhythmia risk because the heat of the sauna enhances adrenergic activity [8]. However, Roine et al. did not find that sauna bathing together with alcohol consumption increased cardiac arrhythmias in healthy young male volunteers [9]. The total time spent in the sauna was between 1 and 3 h, which is normal among Finnish sauna bathers. Not all this time is spent in the steam room, however, as bathers usually take short rests and have a shower or relax outdoors in between. The cycle is typically repeated four to five times. The patients discussed here had been bathing in the company of friends or wives but had then been left alone in the sauna and were found unconscious 30 min to 1 h later. During this relatively short time, they had lost consciousness and been exposed to hot dry air. All the patients in this series suffered from deep tissue burns. The burned areas were on the parts of the body that were directly exposed to hot air; none was in contact with the hot stove. The necrotic area extended to subcutaneous fat tissue and even to the underlying muscles. All patients
underwent an operation whereby the necrotic areas were excised and covered with autologous split thickness skin grafts. The level of excision was typically fascial and, in some areas, layers of the muscle were removed. Our experience shows that affected areas may be unexpectedly badly burned in a layered fashion: there may be some blood circulation in the dermis but the fat and even the muscles underneath are devitalised probably due to slow and long exposure to hot air. Thorough debridement to the well vascularised tissue provided a good wound bed, and good graft intake was noted at follow-up. Contrary to Morris and Rai’s observation, the graft donor areas were normal [10], possibly because our patients had suffered local burns and their position after falling was such that the opposite body parts were not injured. Only one patient required flap reconstruction. He had received a deep burn in his deltoid area and after necrectomy the humeral joint became exposed. This was subsequently covered with a pediculed pectoralis muscle flap. Alcohol consumption results in minor accidents, such as sprains, in the sauna [8]. None of the patients in our series, however, had any wounds or bruises suggesting that they had slipped on the moist sauna floor. All the patients were acutely under the influence of alcohol, the majority quite heavily, with serum alcohol levels ranging from 1.5 to 3.5 mg/100 ml. Moreover, signs of chronic alcohol consumption were noted both in the patients themselves and in their records. Excessive consumption of alcohol together with a hot environment may result in dehydration and eventual loss of consciousness. As a clinical observation, patients with alcohol abuse may require more fluid resuscitation than normal [11]. Dehydration in patients under the influence of alcohol amplifies the risk of hypotension, ethanol as such acting as a diuretic [12]. The risk of hypotension is exacerbated when sauna bathing is combined with alcohol consumption [1,9]. Two patients were diagnosed with brain insults, which became evident at a later stage. One of them suffered massive cerebellar infarction and the other presented with left hemiplegia symptoms. At the same time, these patients were under the influence of alcohol. Neurological examinations were not conducted immediately, because on admission the patients were sedated and intubated. Radiological examinations (CT scans) may therefore be necessary to diagnose the underlying conditions of unconsciousness. The PM and P-CK values of our patients were elevated by several hundred times compared with normal values. The CK value on the second post injury day appears to be the best indicator of prognosis. This finding is supported by Kopp et al., who noted a relation between strongly elevated P-CK levels and mortality in patients with electrical burns [13]. In our series, the P-CK values of the three patients who died were highest on day 2, Table 2. The P-CK level can also be elevated by other events such as pulmonary embolus, stroke, hypothyroidism and intoxication. One of the patients who died (number 6) suffered a large cerebellar infarction in
A. Koski et al. / Burns 31 (2005) 776–779
addition to a burn of 32% TBSA, which was the most extensive burned area in our series. Highly elevated P-CK values are an indicator for the extent and severity of injury. Mortality was 50% in our small series. Rhabdomyolysis associated with burn results in a higher mortality rate than would be expected from the percentage TBSA. A connection between highly elevated PCK values and percentage TBSA was noted. All three diseased patients had the largest burned areas and their P-CK values were highest on day 2, although our patient series was too small to permit an exact numerical value to be deduced for P-CK for prognosis. In conclusion, hot air-induced sauna burns are a rare but potentially fatal injury with subsequent rhabdomyolysis. Alcohol consumption has many harmful effects on the body’s homeostasis such as intervening thermoregulatory mechanisms, causing dehydration and lack of judgement. Considering the potentially dangerous environment, the hot sauna, in which the burns occur it is surprising that these injuries are so rare, even in Finland. Our survey showed that excessive consumption of alcohol is not always the reason for the loss of consciousness. Further radiological and neurological examinations may reveal the underlying factor. In such injuries, mortality exceeds the rate that would be expected from the percentage TBSA. The best prognostic marker for survival was the PCK value on the second post injury day. P-CK values seem to be linked to the severity and extent of the injury. Hot airinduced sauna burns require multidisciplinary expertise to deal with multi-organ dysfunctions and wound care and to plan the timing and strategy of the surgical care.
4. Conflicts of Interest There was no conflict of interest.
779
Acknowledgement The authors thank Dr. Anu Kentta¨ mies, provincial medical examiner for providing the data on hyperthermia deaths in Helsinki and Uusimaa region.
References [1] Hannuksela ML, Ellahham S. Benefits and risks of sauna bathing. Am J Med 2001;110(2):118–26. [2] Kauppinen K. Facts fables about sauna. Ann N Y Acad Sci 1997;813:654–62. [3] Biro S, Masuda A, Kihara T, Tei C. Clinical implications of thermal therapy in lifestyle-related diseases. Exp Biol Med (Maywood) 2003;228(10):1245–9. [4] Kihara T, Biro S, Imamura M, Yoshifuku S, Takasaki K, Ikeda Y, et al. Repeated sauna treatment improves vascular endothelial and cardiac function in patients with chronic heart failure. J Am Coll Cardiol 2002;39(5):754–9. [5] Papp A. Sauna-related burns: a review of 154 cases treated in Kuopio University Hospital Burn Center 1994–2000. Burns 2002;28(1): 57–9. [6] Zeitlin R, Somppi E, Jarnberg J. Paediatric burns in central Finland between the 1960s and the 1980s. Burns 1993;19(5):418–22. [7] Kortelainen ML. Hyperthermia deaths in Finland in 1970–86. Am J Forensic Med Pathol 1991;12(2):115–8. [8] Ylikahri R, Heikkonen E, Soukas A. The sauna and alcohol. Ann Clin Res 1988;20(4):287–91. [9] Roine R, Luurila OJ, Suokas A, Heikkonen E, Koskinen P, Ylikahri R, et al. Alcohol and sauna bathing: effects on cardiac rhythm, blood pressure, and serum electrolyte and cortisol concentrations. J Intern Med 1992;231(4):333–8. [10] Morris AM, Rai S. Sauna bath burn. Br Med J 1978;1(6117):894–5. [11] Yowler CJ, Fratianne RB. Current status of burn resuscitation. Clin Plast Surg 2000;27(1):1–10. [12] Stookey JD. The diuretic effects of alcohol and caffeine and total water intake misclassification. Eur J Epidemiol 1999;15(2):181–8. [13] Kopp J, Loos B, Spilker G, Horch RE. Correlation between serum creatinine kinase levels and extent of muscle damage in electrical burns. Burns 2004;30(7):680–3.