Limitation of this study
Because of donor shortage, many patients are died when they are waiting for lung transplantation. Many innovations about lung transplantation were performed, such as lung preservation method improvement, donor criteria enlargement, and lung transplantation skill improvement. Living lobar transplantation and cadaveric lobar transplantation could be chosen as an alternative when donor and recipient mismatched. Compared with living lobar transplantation, cadaveric lobar transplantation could be more feasible in China. Till now, there were only a few reports about successful bilateral lobar transplantation.
The first and most important step of lobar lung transplantation is to determine which lobar and how many lobars should be transplanted according to chest X-ray comparation.
Patients with CF have small chest cavities as a result of this restrictive lung disease[13]. So the CF patients should be one of the best candidates for lobar transplantation. Now CF represents the most common indication for lobar lung transplantation in the United States[14-16].
However, whether two pulmonary lobes can provide sufficient long-term pulmonary function and clinical outcome to recipients puzzled the surgeon for quite a long time. The question has recently been answered. The USC group reported that living-donor-lobar-lung transplantation provided comparable intermediate- and long-term pulmonary function and exercise capacity to bilateral cadaveric lung transplantation in adult recipients surviving more than 3 months after transplantation[17]. Others also got the same results[18-21]. Six month later, we took some examination for the recipient. Compared with only indoor activity preoperatively, now she could walk 5 000 m outdoor. Her lung function results showed that the forced expiratory volume in one second (FEV1) was 1.78, the FEV1% was 78%, and the maximal voluntary ventilation was 80%. Her performance status score were 0. Though only 6 month postoperatively, we could know that the graft lobe supplied satisfied pulmonary reserve and improved her quality of life.
Then the choice of one lateral lung transplantation or bilateral lung transplantation should be performed. As we know, CF is an infectious disease, and if the infection was not controlled, the lung transplantation should be failure because of graft infection. So we prefer bilateral cadaveric lung transplantation for CF patients.
Mechanical ventilation was used preoperatively because of on-going deterioration of pulmonary function. The benefits of mechanical ventilation preoperatively in this case were: it provided stable cardial and pulmonary function; it elongated waiting time; and also it improved her basic status.
The telescopic-type broncho-bronchial anastomosis was adopted. Both continuous and intermittent suture technique was used. No anastomotic complication occurred postoperatively. And excellent bronchial healing was observed in all anastomoses (Figure 4). We thought various factors might contribute to this, such as short donor bronchial length and well-preserved lung parenchyma with short ischemic time. We also concluded that if the interior diameter of the two bronchial stumps mismatched, the telescopic-anastomosis could be chosen as an alternative.
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The 4 ℃ low potassium dextran was used in infusion and preservation, the pulmonary function was well preserved as reported[22].
Immuno-suppressive drugs were used as soon as possible to prevent acute rejection. The need for optimal immuno-suppression became evident to navigate the delicate balance between infection risk and rejection. Historically, these regimens consisted of cyclosporine[23-24], azathioprine[25], and low-dose prednisone[26]. The combination immunosuppressive therapy consisted of tacrolimus and MMF (35%) most commonly[27-28], followed by tacrolimus and azathioprine (20%), cyclosporin A and MMF (15%), as well as cyclosporin A and azathioprine (5%)[29-30]. However when the three drugs were used as reported, seizure occurred at the 7th and 46th day, and tremor of both hands occurred at the 19th day. However some authors’ reports showed that neural symptom such as seizure, tremor, blindness, and encephalopathy did not necessarily related to elevated levels of cyclosporine or tacrolimus[31]. As usual, the substitution of cyclosporine for tacrolimus, or vice versa, corrected the neurotoxicity, FK506 dosage was down-regulated. And the above symptom disappeared 2 days later. We thought the reason might be over-low weight (37 kg) of the recipient. However, when FK506 was used at semi-dosage, acute rejection was diagnosed by lung biopsy. FK506 was substituted by cyclosporine A and methylprednisolone pulse therapy (360 mg) was used to improve this situation. Although the effectiveness of FK506 was well known, the severe side-effect was also notorious. So the drug concentration should be monitored regularly to predict those severe complications. And in some situations it could be replaced by cyclosporine A if necessarily.
Clinical application significance
Cadaveric lobar transplantation is a safe and effective technology, it could supply enough pulmonary reserve, it could be chosen as an alternative when the donor and recipient mismatched especially for CF patients. With adequate preoperative preparation, skillful surgical technique, and adept application of immunosuppressive drugs, satisfied cadaveric lobar transplantation results could be accomplished.
