Chapter 1494: 1447 Deep Hypothermia

Zheng Ren placed a mattress suture on the anterior outer layer of the ascending aortic root and threaded it into the hemostat.

Then, after purging air from the cardioplegia infusion needle, he stabbed it into the central part of the mattress suture line to enter the ascending aorta.

He tightened the hemostat, secured the cannula and hemostat together with a thick thread, and connected the cannula to the infusion device.

"Zheng Lao Ban, what's the next step?" Lao He asked in advance.

"Left atrium."

"Okay."

The next step of the surgery has two options.

Left atrial drainage or left ventricular drainage.

There are no particular pros and cons, only suitability. For the perfusionist, left atrial and left ventricular drainage differ slightly, and Lao He was showing off his professional details to Zheng Lao Ban.

I'm definitely more suitable than the twin sisters! Zheng Lao Ban, look at me, look at me!

Look here, look here!

Zheng Ren couldn't hear Lao He's inner shout, but he felt the surgery was going much more smoothly than when he was alone in the system operating room.

He made a large mattress suture at the junction of the right upper pulmonary vein root and the left atrium, and placed it in a hemostat.

After making a small opening in the mattress suture ring, he inserted the left atrial drainage tube into the left atrium, tightened the hemostat, and secured the tube with a thick thread, tying the drainage tube to the hemostat and connecting it to the cardiopulmonary bypass machine.

After completing all operations, Zheng Ren once again checked all the tubes and their connections, found no error, confirmed there were no obstructions in any channel, and started cardiopulmonary bypass.

At the moment cardiopulmonary bypass began, Lao He sped up his hand movements.

Although he knew he had already secured first place, he wanted to leave a number that no one could surpass.

Previously, there were few cardiac surgeries numbered 912, and the operators' skill levels were average, so Lao He had no standing in the group.

Although it was just a chat group for idle talk, people with high ability implicitly had some authority.

Those who deal with technology all have similar occupational quirks; even though it's merely a chat and exchange group, they can't avoid being conventional.

This time he must definitely fight for face; Lao He occasionally glanced at the timer.

Although competing for this face is completely meaningless and totally different from the earlier stopped‑heart coronary artery bypass surgeries he used to do.

But even if cardiopulmonary bypass later exits the historical stage, he would still have left a record in the domestic surgical community… and even in the global surgical community!

5′05″!

When he saw this number, he himself felt a bit dazed.

The previous record was 9′22″, but Zheng Lao Ban's surgery actually increased the time to establish cardiopulmonary bypass by nearly double!

Damn, is this something a person can do?

Lao He saw the time, clenched his right hand into a fist, and waved it vigorously.

Done, this is definitely a world record!

Although no one recognizes it, in his heart it is a world record!

After the operation he can go show off in the group, but for now he should focus on assisting Zheng Lao Ban. Though one who has walked a hundred li is only halfway at ninety, he must definitely leave a good impression on Zheng Lao Ban.

A slight oversight beforehand ruins all prior effort.

The twin sisters are such formidable opponents; the pressure is huge. Lao He cautiously observed Zheng Ren's surgical progress from the patient's head position.

After several minutes of cardiopulmonary bypass, Zheng Ren occluded the superior and inferior vena cava, entering full cardiopulmonary bypass.

At this point, the blood from the superior and inferior vena cava flows entirely through the cannula into the cardiopulmonary bypass machine, not into the right atrium.

Simultaneously, blood cooling was carried out.

Lao He continuously reported the blood temperature.

36℃……

35℃……

32℃……

When the body temperature dropped to 30℃, Zheng Ren lifted the ascending aortic tape, used an aortic cross‑clamp, and occluded the ascending aorta.

Su Yun immediately infused 4℃ cardioplegia via the aortic root perfusion line. At the same time, Zhao Yunlong cooled the heart surface with 4℃ icy saline or ice chips to achieve rapid cardiac arrest.

Zheng Ren was very satisfied.

Indeed, the surgical speed was much faster than in the system operating room.

There were two badass doctors capable of performing type A aortic arch replacement as assistants, there was Lao He, an anesthesiologist who could also handle perfusion, and crucially, Xiao Yi Ren was present.

Never mind anything else; Xiao Yi Ren's smiling with curved eyes swept away the fatigue from staying up all night and only catching sleep on the plane.

Compared to this, the experience in the system operating room was extremely poor.

After occluding the ascending aorta, Lao He focused and began continuously reporting various values.

Cardiopulmonary bypass is quite difficult; a slight lapse can cause the patient to never wake up.

"Arterial pressure, 70 mmHg."

"Central venous pressure, 9 cm H₂O."

"Body temperature, 27℃."

"Lao He, lower the temperature a bit more." Zheng Ren lowered his gaze to the operative field while communicating with Lao He.

Normally, maintaining the body temperature around 28℃ during cardiopulmonary bypass is sufficient.

But if the surgeon judges the operation to be very difficult and the procedure unusually long, he will have the perfusionist lower the temperature further.

"How much?" Lao He asked.

"Deep hypothermia, 15℃." Zheng Ren said.

Lao He felt a solemn awe.

Cardioplegia induces cardiac arrest, rapidly stopping all bioelectrical and mechanical activity of the heart, which helps preserve the heart's energy stores.

Supplemented with local deep hypothermia of the heart, it can further reduce myocardial energy and oxygen consumption, and decrease the accumulation of harmful substances such as carbon dioxide, hydrogen ions, and oxygen free radicals.

Deep hypothermia means the Shou Bing duration will exceed three hours.

He immediately began operating the equipment, lowering the temperature.

"Myocardial temperature, 15 degrees Celsius." Lao He said.

"Enough."

"Flow rate, 50–60 ml/kg."

"Lao He, check the blood gas values." Zheng Ren held the blunt scissors, began to dissect the pulmonary artery segment, and communicated with Lao He while speaking.

Speaking did not interfere with Zheng Ren's manual operation; the Shou Bing was extremely precise.

After extracorporeal circulation began, the patient's body temperature fell below 25°C, and the myocardial temperature also dropped to 15°C; Zheng Renxian observed the coronary artery.

The coronary artery was unobstructed, and Zheng Ren began to dissect the pulmonary artery.

The pulmonary valve is located between the right ventricle and the pulmonary artery, preventing backflow of blood ejected into the pulmonary artery back into the right ventricle.

The heart has two atrioventricular valves and two arterial valves.

The pulmonary valve is one of the arterial valves; it has three semilunar cusps. The leaflets and annulus are relatively thin, the annulus attaches to the muscular infundibulum of the right ventricle, and there is no direct fibrous continuity with the tricuspid valve.

The main event had arrived; Zheng Ren hesitated slightly, took a deep breath, held his breath and focused, then began to incise the pulmonary artery at the junction of the left and right cusps.

As the blade descended, Zheng Ren was extraordinarily cautious, more cautious than ever.

He knew that incising the pulmonary artery wall could damage the aorta, and furthermore the location was deep, making hemostasis difficult.

The Willow Leaf Blade made a light touch, then the Hemostatic Forceps were used to separate layer by layer.

Still the smallest size of Hemostatic Forceps, Zheng Ren's fingers could not fit inside, so he had to rely on palpation.

By this point, he still had not used the Microscope.

At this point, the assistant was relatively idle. Su Yun remained silent, instead intently watching Zheng Ren dissect the pulmonary artery.