The author of this article: Yisu
“The mortality rate of heat stroke can reach up to 80% “, “Heat stroke can cause multiple organ failure”, “Man suffers from heat stroke and multiple organs are damaged as if they were boiled”…
In summer, the temperature in various places continues to hit new highs, and heat stroke continues to climb to the top of the hot search. Immediately afterwards, overwhelming popular science followed, telling people that heat stroke is the most serious form of heat stroke.
Similarly, in the 9th edition of Internal Medicine, heat stroke is divided into heat cramps, heat exhaustion, and heat stroke. The three can develop sequentially or overlap.
But we can’t help but wonder, everyone has seen heat stroke, but very few people have seen real heat stroke. Why did those milder forms of heatstroke disappear from the textbook?
Various categories of “heat stroke”< /p>
The debate begins with differences in textbooks.
In the 9th edition of “Internal Medicine”, heat stroke is only divided into 3 categories, and there is no difference in degree. In the 3rd edition of “Emergency and Disaster Medicine” textbook, heatstroke is firstly divided into threatened heatstroke, mild heatstroke and severe heatstroke according to the severity. Heat cramps, heat exhaustion and heat stroke are classified as severe heat stroke.
Edition of “Inner Science” span>
Below: Emergency and Disaster Medicine 3rd Edition
This difference is not limited to domestic textbooks, but is also a common international situation, it is difficult for us to find a unified classification standard.
According to the “American Outdoor Medicine Association Guidelines (2019)”, heat illness is divided into 6 types, mainly based on clinical symptoms And the manifestations are divided into heat edema, heat rash, heat cramps, heat fainting, heat exhaustion and heat stroke.
Source: Reference 1
And edema, rash, cramps, fainting, these are more like specific clinical manifestations, and it seems a bit far-fetched to use as a diagnostic classification. Therefore, many data tend to emphasize the two types of heat exhaustion and heat stroke.
Source: SA Health
Difference from Western countries is that the “Heat Stroke Clinical Practice Guidelines (2015)” published by the Japanese Association of Emergency Medicine divides heat stroke (fever) into 3 degrees from mild to severe. This classification is to avoid underestimating the extent of the disease due to over-attachment to “disordered consciousness, body temperature above 40°C, and stop sweating”. At the same time, for the sake of dissemination, the classification names are also simplified.
Source: Reference 2
It seems that how to classify heat stroke, or whether to classify it by degree, is a long-standing problem.
Clinical and Textbook Gap
“Actually, the students told me about the differences between textbooks on heat stroke classification.” said Hu Junyan, deputy director of the emergency department of the Third Affiliated Hospital of Guangzhou Medical University.
This phenomenon seems to be quite common in textbooks. For example, the data related to vital signs in textbooks are always inconsistent.
Source: Reference 3
Will such differences bring difficulties to clinical admissions?
“It is true that there are more heat stroke patients in contact recently than before.” Hu Junyan revealed, “But to talk about the differences between various types, In fact, the impact is not big.”
There are two important information for the clinical diagnosis of heat stroke: first, the collection of medical history, The second is clinical manifestations.
“Usually what we see is just a fainted patient, and there are no family members around. At this time, there is no way to collect The medical history information.” Zhang Yuanchun, who used to work in the Beijing Emergency Center, said, “For comatose patients,can only be initially suspected of heatstroke based on the weather conditions and the patient’s body surface temperature. Other neurological diseases such as cerebrovascular attacks cannot be excluded.”
“If there is no core It is difficult to distinguish between the two by measuring body temperature.” Zhang Yuanchun added .
Elevated core body temperature is the core clinical manifestation of heat stroke developing into heat stroke, and it is also the most intuitive measurement. data. However, the most recommended method for measuring core temperature is anal temperature measurement. Although it is more convenient than other temperature measurement methods, it is still difficult to achieve clinically.
Source: Expert consensus on emergency diagnosis and treatment of heat stroke (2021)
In addition, although heatstroke can manifest as central nervous system damage and multiple organ failure, these features are obviously not specific. And the key medical history of “continuous exposure to high temperature environment or vigorous exercise” was not inquired. The distance from 120 to the emergency room makes it difficult to even diagnose, let alone grade the disease.
“For clinical work, the most important thing is to rescue the patient. There may also be heat cramps, But usually when encountering severe patients, they tend to diagnose heat stroke. After all, the main first aid measures are the same.” Hu Junyan said.
Changes that never stop, puzzles that never stop
From 1989 to 2019, in the “Diagnostic Criteria for Occupational Heat Stroke”, the classification of heat stroke has been changing. As early as 2002, heatstroke was also classified as threatened heatstroke, mild heatstroke, and severe heatstroke. However, in the latest “Diagnostic Criteria for Occupational Heat Stroke” in 2019, the severity classification of the diagnosis of heat stroke was cancelled.
Source: “Occupational Heat Stroke Diagnostic Criteria (20) span>9)”
Heat stroke expert Professor Song Qing said that the revision of the diagnostic criteria actually It is a reflection of our deepening understanding of heat stroke. In the early days, when we didn’t know it, there was no classification; later, we saw the difference in clinical manifestations and named them with symptoms; and later we had a deeper understanding of the pathogenesis study, suggesting the significance of changes in core temperature and multiple organ failure for the diagnosis.
“The classification of ‘Three Heat Stroke, Mild Heat Stroke, Severe Heat Stroke’ is to hope that everyone realizes that this is a continuous process, so It is necessary to deal with the symptoms in time to prevent further aggravation of the disease.” Professor Song Qing reminded.
In the new edition of “Expert Consensus on Emergency Diagnosis and Treatment of Heat Stroke”, severe heat stroke and heat stroke are equated, not Re-emphasizing the classification of subordinates is to hope that more emergency doctors will pay attention to heat stroke and pay attention to heat stroke. There are many involved organs, severe organ damage, rapid deterioration of the disease, difficult treatment, and high mortality rate – this is Professor Song Qing’s description of heat stroke.
“When a patient has a history of heat exposure and changes in consciousness, we should immediately consider the possibility of heat stroke. Don’t wait until the test results suggest multifunctional organ failure before starting treatment,” added Professor Song Qing. There is no specific diagnostic method for heat stroke, so early identification and timely treatment have become the key.
Back to the original question, repeated revisions are the inevitable result of in-depth clinical practice, and the origin of differences is based on disciplines different considerations behind it.
Planning: ame | Producer: gyouza
< span>Source of title map: Visual China
 Lipman GS, Gaudio FG, Eifling KP, Ellis MA, Otten EM, Grissom CK. Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Heat Illness: 2019 Update. Wilderness Environ Med. 2019 Dec;30(4S):S33-S46. doi: 10.1016/j.wem.2018.10.004. Epub 2019 Jun 17. PMID: 31221601.
 Dal Dili, Wang Lina , Zhang Jixiu, et al. Analysis of the problems in the definition of human vital signs and some laboratory test data in medical textbooks [J]. Health Vocational Education, 2012, 30(14): 132-134. DOI: 10.3969/j.issn.1671 -1246.2012.14.078.
 Song Qing, Mao Handing, Liu Shuyuan, et al. Definition and graded diagnosis of heatstroke [J]. PLA Medical Journal, 2019, 44(7) :541-545.DOI:10.11855/j.issn.0577-7402.2019.07.01.
 Diagnostic criteria for occupational heatstroke: GBZ 41-2002[S]. 2002.
 Diagnostic criteria for occupational heatstroke: GBZ 41-2019[S]. 2019.