With the laparoscopic field of vision magnification, can achieve the fine anatomy of the electric device cutting haemostasis, but ultrasonic knife, electric knife, bipolar and other electric devices to cut tissue proteins or fat when a large number of toxic surgical smoke, these fumes in a small space to gather, very easy to blur the lens, affecting the coherence of surgical operations, resulting in prolonged operating time. It increases the risk of surgery, and the emission into the operating theatre or accumulation in the patient's body will endanger the health of the medical staff and the patient. In addition, the formation of pneumoperitoneum in laparoscopic surgery carbon dioxide also has toxic side effects. These adverse effects have attracted much attention from clinicians. Therefore, it is extremely important to discharge the smoke in a timely manner to ensure a clear operative field.

1. Connect the infusion set through the valve of the puncture device and immerse the other end in saline, but the effect is poor and the odour is pungent.
2. Connect the suction tube through the infusion device, which is effective but not easy to operate and has the risk of stabbing, the connection is not tight, the air tightness is not good, which affects the effect of smoke evacuation and suction. Connecting suction tube through rubber tube + syringe needle, the rubber tube is soft and easy to be deflated and lose its function and there is the risk of needle stick injury.
3. External suction line, exhaust quickly and clearly, but need to prepare two sets of negative pressure suction device.
4. Specialised smoke evacuation auxiliary equipment, high cost.
5. Use suction to suction out the smoke in the abdominal cavity, but when using suction, you need to change the operating instruments, which increases the operation time and the bleeding time of the wound.
The above smoke removal methods found that all methods are inseparable from the negative pressure suction device, so my department designed a metal tee device, clever use of 8mm metal tee connected to a disposable suction tube will be artificially divided into two negative pressure suction suction suction device, all the way for suction all the way for smoke removal, clinical development has achieved good results.

Advantages and innovation points:
1、The diameter of the tee tube is the same as that of the suction tube, which makes the smoke evacuation speed fast, the operation field clear, and reduces the number of times of deflating the exhaust hole and the number of times of eyepiece wiping during the operation.
2、Reduce the use of sharps (infusion needles) to avoid the risk of needlestick injury.
3、Only one negative pressure suction device is used, with low running cost.
4. The metal tee can be sterilised and reused repeatedly, without increasing the cost of surgery for patients.
5. Easy to carry, easy to move, one person can use, reduce the labour of medical staff.
Disadvantages: need to assemble and timely adjustment of the valve, not suitable for single-hole laparoscopic surgery.

Use effect:
1.Keeping clear vision, reducing the operation risk caused by unclear vision, thus reducing intraoperative bleeding.
2、Reduce the number of times to wipe the lens, avoid waiting for the field of vision to become clear, thus shortening the operation time reduce the patient's injection of anaesthesia, shorten the patient's awakening time, shorten the operation time.
3、Improve the doctor's satisfaction with the surgical co-operation and guarantee the smooth operation.