[Connotation of Xiao Chaihu Decoction combined with Maxing Shigan Decoction based on severe cases and modern pathophysiological mechanism and application for severe pulmonary infection and acute exacerbation of chronic obstructive pulmonary disease in critical care medicine].

Xiao Chaihu Decoction combined with Maxing Shigan Decoction is a classic herbal formula. All of them are derived from Treatise on Cold Damage(Shang Han Lun) by ZHANG Zhong-jing. This combination has the effects of harmonizing lesser yang, relieving exterior syndrome, clearing lung heat, and relieving panting. It is mainly used for treating the disease involving the triple-Yang combination of diseases and accumulation of pathogenic heat in the lung. Xiao Chaihu Decoction combined with Maxing Shigan Decoction is a classic combination for the treatment of exogenous diseases involving the triple-Yang combination. They are commonly used in exogenous diseases, especially in the north of China. This combination is also the main treatment strategy for coronavirus disease 2019(COVID-19) accompanied by fever and cough. Maxing Shigan Decoction is a classical herbal formula for treating the syndrome of phlegm-heat obstructing the lung. "Dyspnea after sweating" suggests the accumulation of pathogenic heat in the lung. Patients with mild symptoms may develop cough and asthma along with forehead sweating, and those in critical severe may develop whole-body sweating, especially the front chest. Modern medicine believes that the above situation is related to lung infection. "Mild fever" refers to syndromes rather than pathogenesis. It does not mean that the heat syndrome is not heavy, instead, it suggests that severe heat and inflammation have occurred. The indications of Xiao Chaihu Decoction combined with Maxing Shigan Decoction are as follows.(1) In terms of diseases, it is suitable for the treatment of viral pneumonia, bronchopneumonia, lobar pneumonia, mycoplasma pneumonia, COVID-19 infection, measles with pneumonia, severe acute respiratory syndrome(SARS), avian influenza, H1N1 influenza, chronic obstructive pulmonary disease with acute exacerbation, pertussis, and other influenza and pneumonia.(2) In terms of syndromes, it can be used for the syndromes of bitter mouth, dry pharynx, vertigo, loss of appetite, vexation, vomiting, and fullness and discomfort in the chest and hypochondrium. It can also be used to treat alternate attacks of chill and fever and different degrees of fever, as well as chest tightness, cough, asthma, expectoration, dry mouth, wanting cold drinks, feeling agitated, sweating, yellow urine, dry stool, red tongue, yellow or white fur, and floating, smooth, and powerful pulse, especially the right wrist pulse.

[Treatment strategy and thought on classical herbal formulae for coronavirus disease 2019].

Coronavirus disease 2019(COVID-19) refers to the pneumonia caused by novel coronavirus(2019-nCoV) infection in 2019. It is highly infectious, with quick spreading and a wide range of impact. It has been broken out in many countries around the world and has become a public health emergency of international concern. Chinese medicine has a long history in treating plague, and viral disease is the clinical advantage in Chinese medicine. Under the premise that there is currently no specific drug treatment, Chinese medicine has achieved certain effects in the treatment of COVID-19, which has attracted much attention and has been upgraded to a national strategy. Regarding the treatment of COVID-19 with Chinese medicine, it is believed that in terms of the name of Chinese medicine, the modern connotation of "uniform of typhoid and febrile disease" should be re-recognized, and it is advisable to use drugs based on specific clinical prescriptions and indications. In terms of pathogenesis, the COVID-19 has the pathogenesis rules including from the mild to severe conditions, from the surface to the inside, from the excess syndrome to the deficiency syndrome. We should pay attention to the Taiyang syndrome damaged by wet disease in initial stage, Shaoyang syndrome complicated with Yangming syndrome in the middle stage, phlegm-heat obstructing lung in critical period, lung and spleen deficiency in the recovery stage. In terms of clinical treatment strategies, Dayuan Yin is recommended to induce sweat and disperse the stasis in early stage. Xiaochaihu Decoction and Maxing Shigan Decoction is used to relieve both exterior and interior symptoms in middle stage. In critical stage, Tingli Dazao Xiefei Decoction, Weijing Decoction, Xuanbai Chengqi Decoction, Xiaoxianxiong Decoction, and Sanzi Yangqin Decoction are considered to reduce phlegm and clear heat. We should pay attention to nourishing Qi and strengthening the spleen by Zhuye Shigao Decoction, Sha-shen Maidong Decoction, and Liujunzi Decoction in the later recovery period. It shall be noted that, no matter in the initial mild stage, the middle and critical stages, or in the later recovery stage, Chinese medicine plays an important role, including preventing mild to severe disease, shortening the fever time, improving cough symptoms, increasing blood oxygen saturation and reducing mortality. Many studies have shown that the classical herbal formulae can alleviate the cytokine storm, regulate the immune imbalance, and produce the potential effect of synergistic treatment for COVID-19 through multiple components, multiple targets, and multiple pathways.