Background:Aeromedical evacuation of patients with burn trauma is an important transport method in times of peace and war,during which patients are exposed to prolonged periods of hypobaric hypoxia;however,the effects...Background:Aeromedical evacuation of patients with burn trauma is an important transport method in times of peace and war,during which patients are exposed to prolonged periods of hypobaric hypoxia;however,the effects of such exposure on burn injuries,particularly on burn-induced lung injuries,are largely unexplored.This study aimed to determine the effects of hypobaric hypoxia on burn-induced lung injuries and to investigate the underlying mechanism using a rat burn model.Methods:A total of 40 male Wistar rats were randomly divided into four groups(10 in each group):sham burn(SB)group,burn in normoxia condition(BN)group,burn in hypoxia condition(BH)group,and burn in hypoxia condition with treatment intervention(BHD)group.Rats with 30%total body surface area burns were exposed to hypobaric hypoxia(2000 m altitude simulation)or normoxia conditions for 4 h.Deoxyribonuclease I(DNase I)was administered systemically as a treatment intervention.Systemic inflammatory mediator and mitochondrial deoxyribonucleic acid(mtDNA)levels were determined.A histopathological evaluation was performed and the acute lung injury(ALI)score was determined.Malonaldehyde(MDA)content,myeloperoxidase(MPO)activity,and the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3(NLRP3)inflammasome level were determined in lung tissues.Data among groups were compared using analysis of variance followed by Tukey’s test post hoc analysis.Results:Burns resulted in a remarkably higher level of systemic inflammatory cytokines and mtDNA release,which was further heightened by hypobaric hypoxia exposure(P<0.01).Moreover,hypobaric hypoxia exposure gave rise to increased NLRP3 inflammasome expression,MDA content,and MPO activity in the lung(P<0.05 or P<0.01).Burn-induced lung injuries were exacerbated,as shown by the histopathological evaluation and ALI score(P<0.01).Administration of DNase I markedly reduced mtDNA release and systemic inflammatory cytokine production.Furthermore,the NLRP3 inflammasome level in lung tissues was decreased and burn-induced lung injury was ameliorated(P<0.01).Conclusions:Our results suggested that simulated aeromedical evacuation further increased burn-induced mtDNA release and exacerbated burn-induced inflammation and lung injury.DNase I reduced the release of mtDNA,limited mtDNA-induced systemic inflammation,and ameliorated burn-induced ALI.The intervening mtDNA level is thus a potential target to protect from burn-induced lung injury during aeromedical conditions and provides safer air evacuations for severely burned patients.展开更多
BACKGROUND： Hiking is a very popular sport in Hong Kong. Serious injuries can sometimes occur in the remote areas not accessible to roads. Aeromedical evacuation service is run by the Government Flying Service （GFS...BACKGROUND： Hiking is a very popular sport in Hong Kong. Serious injuries can sometimes occur in the remote areas not accessible to roads. Aeromedical evacuation service is run by the Government Flying Service （GFS） with emergency physicians and nurses as volunteers in Hong Kong. In this paper we describe the pro？ le and outcome of injured hikers rescued by the GFS.METHODS： In this retrospective review, nature of the complaints, medical team composition, vital signs, clinical assessment and diagnosis on site were collected from the GFS medical record. Demographic data, final diagnoses and outcomes of the patients were retrieved from emergency department （ED） and hospital discharge records.RESULTS： A total of 275 cases were recruited for the 3-year period from January 2003 to December 2005. The mean age of the group was 39 years （range 1-83） with more males （159, 58%） than females. Heat illnesses, injuries and medical problems each constituted about one third of the cases. Lower limb injuries accounted for nearly half of the injuries. About 30% of the rescued hikers did not register to be seen at the ED. Only 48 hikers （17.5%） required admission and four were admitted to intensive/coronary care units for heat stroke and acute coronary syndrome. Five cases of pre-hospital cardiac arrest were recorded.CONCLUSION： Most hikers evacuated by the GFS did not suffer from serious conditions. GFS should still be prepared for the occasional cases that require advanced life support.展开更多
BACKGROUND With very high mortality and disability rates,cerebrovascular diseases and intracranial tumors severely threaten the health and fighting strength of flying personnel,requiring great concern and intensive sc...BACKGROUND With very high mortality and disability rates,cerebrovascular diseases and intracranial tumors severely threaten the health and fighting strength of flying personnel,requiring great concern and intensive screening in clinic,early warning in an early and accurate manner and early intervention of diseases possibly resulting in inflight incapacitation are key emphases of aeromedical support in clinic.AIM To probe into the spectra of intracranial diseases,flight factors and medical imaging characteristics of military pilots(cadets)in the physical examination for transfer to pilot modified high performance aircraft,thus rendering theoretical references for clinical aeromedical support of pilots.METHODS A total of 554 military pilots(cadets)undergoing physical examination for transfer to pilot modified high performance aircraft from December 2020 to April 2024 in a military medical center were enrolled in this study.Then,a retrospective study was carried out on intracranial disease spectra and head magnetic resonance imaging(MRI)data of 36 pilots(cadets)who were unqualified for transfer to pilot modified high performance aircraft.Besides,a descriptive statistical analysis was conducted on the clinical data,age,fighter type and head MRI data of such pilots(cadets).RESULTS Abnormal head images were found in 36 out of 554 pilots(cadets)participating in the physical examination for transfer to pilot modified high performance aircraft,including arachnoid cyst in 17(3.1%)military pilots(cadets),suspected very small aneurysm in 11(2.0%),cavernous hemangioma in 4(0.7%),vascular malformation in 2(0.4%),and pituitary tumor in 3(0.5%,one of which developed cavernous hemangioma simultaneously).Among the 17 pilots(cadets)with arachnoid cyst,4 were identified as unqualified for transfer to pilot modified high performance aircraft because the marginal brain tissues were compressed by the cyst>6 cm in length and diameter.The 11 pilots(cadets)with suspected very small aneurysms identified by 3.0T MRI consisted of 6 diagnosed with conus arteriosus by digital subtraction angiography and qualified for transfer to pilot modified high performance aircraft,and 5 identified as very small intracranial aneurysms with diameter<3 mm and unqualified for transfer to pilot modified high performance aircraft.No symptoms and signs were observed in the 4 military pilots(cadets)with cavernous hemangioma,and the results of MRI revealed bleeding.The 1 of the 4 had the lesion located in pons and developed Rathke cyst in pituitary gland at the same time,and unqualified for transfer to pilot modified high performance aircraft.The 2 of the 4 were unqualified for flying,and 2 transferred to air combat service division.The 2 pilots(cadets)with vascular malformation were identified as unqualified for transfer to pilot modified high performance aircraft.Among the 3 pilots(cadets)with pituitary tumor,one pilot cadet was identified as unqualified for flying since the tumor compressed the optic chiasma,one had cavernous hemangioma in pons in the meantime and transferred to air combat service division,and one was diagnosed with nonfunctional microadenoma and qualified for transfer to pilot modified high performance aircraft.CONCLUSION High-resolution head MRI examination is of great significance for screening and detecting cerebrovascular diseases and intracranial tumors in military flying personnel,and attention should be paid to its clinical application to physical examination for transfer to pilot modified high performance aircraft.展开更多
基金supported by the Youth Incubation Project from the Sanitary Bureau of Logistics Security Ministry of the Central Military Commission(19QNP025)Major Applied Basic Research Project from the Logistics Security Ministry of the Central Military Commission(AKJ15J001)。
文摘Background:Aeromedical evacuation of patients with burn trauma is an important transport method in times of peace and war,during which patients are exposed to prolonged periods of hypobaric hypoxia;however,the effects of such exposure on burn injuries,particularly on burn-induced lung injuries,are largely unexplored.This study aimed to determine the effects of hypobaric hypoxia on burn-induced lung injuries and to investigate the underlying mechanism using a rat burn model.Methods:A total of 40 male Wistar rats were randomly divided into four groups(10 in each group):sham burn(SB)group,burn in normoxia condition(BN)group,burn in hypoxia condition(BH)group,and burn in hypoxia condition with treatment intervention(BHD)group.Rats with 30%total body surface area burns were exposed to hypobaric hypoxia(2000 m altitude simulation)or normoxia conditions for 4 h.Deoxyribonuclease I(DNase I)was administered systemically as a treatment intervention.Systemic inflammatory mediator and mitochondrial deoxyribonucleic acid(mtDNA)levels were determined.A histopathological evaluation was performed and the acute lung injury(ALI)score was determined.Malonaldehyde(MDA)content,myeloperoxidase(MPO)activity,and the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3(NLRP3)inflammasome level were determined in lung tissues.Data among groups were compared using analysis of variance followed by Tukey’s test post hoc analysis.Results:Burns resulted in a remarkably higher level of systemic inflammatory cytokines and mtDNA release,which was further heightened by hypobaric hypoxia exposure(P<0.01).Moreover,hypobaric hypoxia exposure gave rise to increased NLRP3 inflammasome expression,MDA content,and MPO activity in the lung(P<0.05 or P<0.01).Burn-induced lung injuries were exacerbated,as shown by the histopathological evaluation and ALI score(P<0.01).Administration of DNase I markedly reduced mtDNA release and systemic inflammatory cytokine production.Furthermore,the NLRP3 inflammasome level in lung tissues was decreased and burn-induced lung injury was ameliorated(P<0.01).Conclusions:Our results suggested that simulated aeromedical evacuation further increased burn-induced mtDNA release and exacerbated burn-induced inflammation and lung injury.DNase I reduced the release of mtDNA,limited mtDNA-induced systemic inflammation,and ameliorated burn-induced ALI.The intervening mtDNA level is thus a potential target to protect from burn-induced lung injury during aeromedical conditions and provides safer air evacuations for severely burned patients.
文摘BACKGROUND： Hiking is a very popular sport in Hong Kong. Serious injuries can sometimes occur in the remote areas not accessible to roads. Aeromedical evacuation service is run by the Government Flying Service （GFS） with emergency physicians and nurses as volunteers in Hong Kong. In this paper we describe the pro？ le and outcome of injured hikers rescued by the GFS.METHODS： In this retrospective review, nature of the complaints, medical team composition, vital signs, clinical assessment and diagnosis on site were collected from the GFS medical record. Demographic data, final diagnoses and outcomes of the patients were retrieved from emergency department （ED） and hospital discharge records.RESULTS： A total of 275 cases were recruited for the 3-year period from January 2003 to December 2005. The mean age of the group was 39 years （range 1-83） with more males （159, 58%） than females. Heat illnesses, injuries and medical problems each constituted about one third of the cases. Lower limb injuries accounted for nearly half of the injuries. About 30% of the rescued hikers did not register to be seen at the ED. Only 48 hikers （17.5%） required admission and four were admitted to intensive/coronary care units for heat stroke and acute coronary syndrome. Five cases of pre-hospital cardiac arrest were recorded.CONCLUSION： Most hikers evacuated by the GFS did not suffer from serious conditions. GFS should still be prepared for the occasional cases that require advanced life support.
基金Supported by The Key Projects of Medical Service Scientific Research of the Navy Medical Center,China,No.20M2302.
文摘BACKGROUND With very high mortality and disability rates,cerebrovascular diseases and intracranial tumors severely threaten the health and fighting strength of flying personnel,requiring great concern and intensive screening in clinic,early warning in an early and accurate manner and early intervention of diseases possibly resulting in inflight incapacitation are key emphases of aeromedical support in clinic.AIM To probe into the spectra of intracranial diseases,flight factors and medical imaging characteristics of military pilots(cadets)in the physical examination for transfer to pilot modified high performance aircraft,thus rendering theoretical references for clinical aeromedical support of pilots.METHODS A total of 554 military pilots(cadets)undergoing physical examination for transfer to pilot modified high performance aircraft from December 2020 to April 2024 in a military medical center were enrolled in this study.Then,a retrospective study was carried out on intracranial disease spectra and head magnetic resonance imaging(MRI)data of 36 pilots(cadets)who were unqualified for transfer to pilot modified high performance aircraft.Besides,a descriptive statistical analysis was conducted on the clinical data,age,fighter type and head MRI data of such pilots(cadets).RESULTS Abnormal head images were found in 36 out of 554 pilots(cadets)participating in the physical examination for transfer to pilot modified high performance aircraft,including arachnoid cyst in 17(3.1%)military pilots(cadets),suspected very small aneurysm in 11(2.0%),cavernous hemangioma in 4(0.7%),vascular malformation in 2(0.4%),and pituitary tumor in 3(0.5%,one of which developed cavernous hemangioma simultaneously).Among the 17 pilots(cadets)with arachnoid cyst,4 were identified as unqualified for transfer to pilot modified high performance aircraft because the marginal brain tissues were compressed by the cyst>6 cm in length and diameter.The 11 pilots(cadets)with suspected very small aneurysms identified by 3.0T MRI consisted of 6 diagnosed with conus arteriosus by digital subtraction angiography and qualified for transfer to pilot modified high performance aircraft,and 5 identified as very small intracranial aneurysms with diameter<3 mm and unqualified for transfer to pilot modified high performance aircraft.No symptoms and signs were observed in the 4 military pilots(cadets)with cavernous hemangioma,and the results of MRI revealed bleeding.The 1 of the 4 had the lesion located in pons and developed Rathke cyst in pituitary gland at the same time,and unqualified for transfer to pilot modified high performance aircraft.The 2 of the 4 were unqualified for flying,and 2 transferred to air combat service division.The 2 pilots(cadets)with vascular malformation were identified as unqualified for transfer to pilot modified high performance aircraft.Among the 3 pilots(cadets)with pituitary tumor,one pilot cadet was identified as unqualified for flying since the tumor compressed the optic chiasma,one had cavernous hemangioma in pons in the meantime and transferred to air combat service division,and one was diagnosed with nonfunctional microadenoma and qualified for transfer to pilot modified high performance aircraft.CONCLUSION High-resolution head MRI examination is of great significance for screening and detecting cerebrovascular diseases and intracranial tumors in military flying personnel,and attention should be paid to its clinical application to physical examination for transfer to pilot modified high performance aircraft.
