How to Judge Whether the Veress Needle Has Entered the Abdominal Cavity

The veress needle use is the first step in the official start of laparoscopic surgery, and it is also the most dangerous step. The data show that, among the complications of laparoscopic surgery, the complications related to the veress needle and the first puncture account for more than half. It is easy to understand that only this step in the laparoscopic operation cannot be completed under the surveillance of the laparoscope. Therefore, paying attention to the details of the veress needle puncture is of great benefit to improving the safety of the operation.

1. The method of judging the entry of the veress needle into the abdominal cavity: observe the abdominal pressure reading

If there are two obvious breakthroughs, it often indicates that the veress needle has entered the abdominal cavity. There are other clinical methods to judge whether the veress needle is safe to enter the abdominal cavity. For example, observing the abdominal pressure readings on the pneumoperitoneum machine, which is often used. After the inflation tube is connected to the veress needle, the abdominal pressure is negative at the beginning (not necessarily all of them), and as the inflation progresses, the reading slowly rises, indicating that the veress needle has entered the abdominal cavity. If the reading is above 15mmHg at the beginning of inflation, the reading does not decrease after adjusting the direction of the veress needle left and right, and the air intake rate slows down or drops to zero, it is likely that the veress needle tip is still in the abdominal wall tissue.

2. The method of judging whether the veress needle has entered the abdominal cavity: the syringe of normal saline is connected to the veress needle

Another method is mentioned in many related books, which is to judge by connecting a syringe filled with normal saline to a veress needle. The method is to take a 5-10ml syringe, fill it with normal saline, and connect the veress needle. Continue to withdraw until the plunger is pulled out and observe whether blood or other fluid is drawn. After pulling out the piston, if the veress needle has entered the abdominal cavity, the water in the syringe will slowly flow in, and the liquid level in the syringe will drop steadily. If the veress needle does not fully enter the abdominal cavity and the needle tip is still in the abdominal wall tissue, the liquid level of the syringe will not drop smoothly. This approach looks good, but its practical value is debatable. If the puncture enters the blood vessel, although this rarely happens, if it happens, it usually enters the large abdominal blood vessel, and blood will be ejected through the puncture needle without withdrawing; when entering the intestinal tube, the fluid level in the syringe should also drop. This approach is of little value in critical situations. In addition, this method is not as simple as the previous method, so this judgment method is rarely used.

Surgeons are often more worried about the entry of the veress needle into the intestinal tube. There is a saying that the syringe is connected to the veress needle and withdrawn. If the intestinal fluid is extracted, it can be clear. But the question is, if the fluid can't be pumped out, must it not enter the bowel? If fluid is withdrawn, how can you tell if it is ascites or intestinal fluid? For those with high risk of abdominal wall adhesion and easy puncture into the bowel, the safest method is to use open placement.