Four medical teams from the Peking Union Medical College Hospital (PUMCH) in Beijing are in Wuhan to help treat the most severe coronavirus cases.

Doctors from the teams are checking on a patient recovering from COVID-19  at Wuhan's Tongji Hospital. After two weeks of treatment, the once-severely ill patient has regained consciousness and is able to move.

Dr. Zhou Xiang from PUMCH says it's vital to give severely ill patients mechanical ventilation and oxygen support early and quickly.

He adds that antiviral and anti-inflammatory therapies and multiple organ support are also needed. And the details of treatment play an important role in deciding whether patients improve. Take the management of blood pressure, blood volume and blood sugar for example. Good handling of these details will further create conditions for lung recovery and protect patients' other organs.

As we follow the doctors making their rounds, we discover that some patients' fingertips and toes have turned purple or even black. This symptom with black fingertips is caused by severe blood clotting, which can happen as a result of various diseases. It's a condition called disseminated intravascular coagulation, or DIC. It's commonly seen in patients who are very gravely ill. But for the first time, doctors from the Peking Union Medical College Hospital have found that it has a direct link with the new virus.

It's normal to see this in dying patients. But the doctors from Beijing also found the symptom in moderate infections.

Dr. Li Taisheng from PUMCH says some of his patients had just started to use ventilators or take in high-flow oxygen when their fingertips and toes became cold. Some turned purple, with the worst cases turning black.

Therefore, the medical team concluded that COVID-19 can damage the blood circulation system and cause clotting. They've turned to blood specialists at PUMCH's Beijing headquarters and have started to take anti-blood-clotting precautions for their patients.

"Fingers and toes are easy to observe and the effect of treatment is easy to see from the outside. More importantly, the same thing is happening to organs that we can't see from the outside," says Han Ding, PUMCH's vice-president.

In the first two weeks after the first medical team's arrival, severe cases that were moved to ICU survived only three days on average. But after adopting the anti-blood-clotting treatment, doctors here have been able to extend the lives of the critically ill for two or three weeks.

Zhang Shuyang, secretary of CPC Party Committee at PUMCH, says even though they had never experienced COVID-19 before, the changes in bodily functions caused by the virus are not new. So patients can be treated even though there isn't a cure. Basic medical skills, along with a thorough understanding of body functions, can help them win the battle against the virus.

The medical teams now have a new understanding of patient management. They are concentrating their efforts on treating patients in critical condition, but they are also studying the progression of the illness to learn how to prevent mild cases from becoming severe.