1.Surgical indications
Locally advanced non-small cell lung cancer invades the superior vena cava more than one-third of its circumference; or invades the superior vena cava and penetrates into the superior vena cava or has formed a cancer thrombus in the superior vena cava, but there is no cancer thrombus in the left and right unnamed veins, there is no distant metastasis, and local radical resection is possible. For locally advanced non-small cell lung cancer that invades the superior vena cava and does not exceed one-third of its circumference, partial resection of the superior vena cava wall plus vena cava reconstruction is feasible.
Correct case selection, rational design, and selection of surgical style are the keys to ensure the success of surgery. Preoperative CT and superior vena cava angiography can be used to clarify the location, extent and degree of invasion of the lesion, and sometimes it is not easy to determine whether or not to perform the procedure before surgery, and the decision often needs to be based on the specific intraoperative exploration.
2.Cautions.
Preoperatively.
① Selection of artificial blood vessels: There are various artificial blood vessels used in clinical practice. Our department often uses polytetrafluoroethylene expanded artificial blood vessels with rings. The choice of diameter size should be determined according to the imaging results, and those who are not suitable for imaging should be speculated according to the chest CT.
② Preoperatively, a right internal jugular vein indwelling needle is placed and connected to a sterile anticoagulated blood collection bag for blood release and decompression.
③ Preoperatively, a right saphenous vein was punctured, a floating catheter was implanted, and an invasive blood pressure monitor was connected.
④ Closely observe the changes in venous pressure in the upper and lower extremities.
Intraoperatively.
① To prevent thrombosis, systemic heparinization was performed.
② Controlled hypotension before blocking the superior vena cava.
③During blockade of the superior vena cava, if the blood pressure in the right anomalous vein exceeds 50 cm water column, bleed and decompress through an indwelling needle in the internal jugular vein, and the recovered blood is returned through the veins of the lower extremities.
④After resection of the diseased superior vena cava, the length of the distal and proximal stump should be maintained at 0.3-0.5 cm to facilitate the anastomosis of the artificial vessel for reconstruction, but at the same time, the negative cut edge should be ensured to avoid residual tumor.
⑤ Replacement of the artificial vessel to reconstruct the superior vena cava. Our approach is to use an expanded artificial vessel with ring polytetrafluoroethylene, 15 mm in diameter. The length of the artificial vessel should be trimmed according to the length of the superior vena cava defect, and the length should be appropriate; if it is long, it is easy to twist into an angle, and if it is short, the anastomosis is easy to have tension.
The distal end of the artificial vessel is anastomosed end to end with a 5-0 Prilling thread with continuous external sutures at the confluence of the left and right unnamed veins, and the proximal end of the artificial vessel is anastomosed end to end with continuous external sutures at the stump of the superior vena cava at the right atrium, the last stitch is not tightened for the time being, and the blocking band at the left and right unnamed veins is loosened to completely drain the air inside the artificial vessel, and then the sutures are tightened and knotted.
(6) Appropriate external fixation of the artificial blood vessel to prevent angulation.
3.Postoperative treatment
Superior vena cava replacement is very traumatic, the operation time is long, and cardiopulmonary complications are very likely to occur after the operation, so the indications for the operation must be strictly controlled before the operation, and the changes in the condition should be closely monitored after the operation, and effective treatment should be made in time.
In addition to routine management, special attention should be paid to the following issues.
① Leave a CVP catheter in place and monitor central venous pressure.
② Strictly control the amount of fluid intake and the rate of infusion per unit of time, and the negative balance of body fluid should be 500 ml per day.
③Routine postoperative administration of tachyphylaxis, 20 mg/time, twice a day.
④Anticoagulation therapy: Immediately after surgery, dipyridamole should be given intramuscularly, 10 mg/time, three times a day, and after removal of the chest tube the oral warfarin should be given to prolong the prothrombin time by 1.5 times.
⑤ Closely observe the changes of venous pressure in the upper and lower limbs, and assess the patency of the blood vessels in time.
⑥Start a 4-week adjuvant chemotherapy one month after surgery, followed by sequential radiotherapy or, if physically possible, simultaneous radiotherapy and chemotherapy. The superior vena cava replacement technique completely resects lung cancer and relieves superior vena cava obstruction, which not only improves patients’ survival quality, but also enables a considerable number of patients to obtain long-term survival, which is worth advocating.