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Bronchial, pulmonary artery, and donor left atrial anastomoses (left atrial patch includes the pulmonary vein orifices) are performed.

The bronchial anastomosis is performed by using a telescoping interrupted suture technique. Wrapping the bronchial anastomosis with a vascularized pedicle of omentum has also been used.

Induction therapy with antilymphocyte sera and avoidance of high-dose steroids (which inhibit bronchial anastomotic healing) is often chosen.

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Double-lung transplants are usually performed through a transverse anterior thoracotomy with or without cardiopulmonary bypass, and the procedure resembles two single -lung transplants. The two bronchial anastomoses are performed like single -lung transplants.

D Postoperatively

the new lung(s) rapidly accommodate, and prompt extubation is the rule. Both rejection and infection are monitored with serial chest radiographs, bronchoscopy with bronchoalveolar lavage or transbronchial biopsy, and measurements of forced expiratory volume in 1 second (FEV 1 , only for rejection surveillance).

E

Donors are scarce because prolonged intubation, chest contusions, aspiration injury, and pneumonia—any of which may contraindicate lung donation—are all common in brain-dead individuals. Bronchoscopy is required before donation and is often performed in the operating room just before the donor surgery.

F Complications and results

Acute rejection is characterized by fever, infiltrates on a chest radiograph, worsened blood gas exchange, and exclusion of infection by bronchoalveolar lavage. The incidence of acute rejection is 60%.

Bronchial anastomotic complications occur in approximately 15% of recipients and are treated with various methods from observation through surgical repair or stent placement. Complete breakdown or dehiscence of the bronchial anastomosis requires surgical repair or retransplantation.

Pneumonia is a common source of morbidity and potential mortality. The prevalence of bacterial pneumonia is 50%. The prevalence of CMV pneumonia varies with the serostatus (prior infection) of the donor and the recipient, but it can be fatal and prophylaxis is required. Fungal infection is uncommon (<10%) but is usually lethal.

Survival is similar for single -lung, double -lung, and heart -lung transplantation, with a 70% 1-year survival rate. Chronic rejection is a significant long-term problem. It is diagnosed histologically as bronchiolitis obliterans or clinically as bronchiolitis obliterans syndrome. Mortality with this diagnosis is high (40% within 2 years).

Survival by diagnosis , from best to worst, is as follows:

Obstructive lung disease

Cystic fibrosis

Restrictive lung disease

Pulmonary hypertension

IV Hepatic Transplantation

Hepatic transplantation is technically difficult because portal hypertension, portosystemic venous collaterals, and coagulopathy are usually present. The postoperative course depends on the initial condition of the patient, the function of the new liver, and technical problems in the perioperative period.

A

Candidates have end -stage liver disease and are likely to die within 1–2 years without transplantation. Most candidates are between 6 months and 70 years of age. Careful evaluation of cardiopulmonary and renal function is essential. Once listed, priority is based on their MELD (Model for End -stage Liver Disease) score. The score is based on bilirubin, creatinine, and international normalized ratio (INR) and ranges from a minimum of 6 to a maximum of 40. The sicker the patient, the higher the values, and the higher the MELD score. Since priority is based on MELD, severity of disease is emphasized rather than waiting time.

B Indications for liver transplantation

Approximately 95% of candidates have chronic disease; the remaining 5% have fulminant hepatic failure , which is a disorder that progresses rapidly.

Adults. In adults, the common chronic diseases that require liver transplantation include cirrhosis from chronic hepatitis C (40%), alcoholic cirrhosis (15%), chronic hepatitis B (<10%), primary biliary cirrhosis (<10%), and primary sclerosing cholangitis (<10%).

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Children. In children who require liver transplantation, more than 50% have biliary atresia as the cause of liver failure.

Three major complications herald end -stage liver disease and indicate the need to consider liver transplantation.

Difficult-to -manage ascites (refractory to treatment, associated with spontaneous bacterial peritonitis, or hydrothorax from peritoneal–pleural leaks)

Encephalopathy

Esophageal variceal hemorrhage (recurrent or associated with hepatic decompensation)

C Four areas of controversy

Alcoholic patients with cirrhosis have the same chance for successful transplantation as do patients with other diagnoses. However, they require screening to identify and exclude those who are likely to return to drinking. Most programs require a minimum of 6 months of abstinence. Alcoholic patients with cardiomyopathy and cerebral atrophy must be excluded.

Patients with fulminant hepatic failure can develop cerebral edema, herniation, and brain death. When fulminant hepatic failure results from a suicide attempt (classically from acetaminophen overdose), the patient can be excluded if the psychiatric history has documented multiple suicide attempts.

Patients with primary hepatic malignancies treated with transplantation have high recurrence rates and a poorer outcome. Therefore, their suitability as candidates is controversial. However, candidates with cirrhosis and a single, small (<5 cm) hepatocellular carcinoma that is not amenable to resection do not have a substantial risk of recurrence and are good candidates.

Patients with cirrhosis from chronic viral hepatitis face risks of recurrent hepatitis and the potential for recurrent cirrhosis. Treatment varies with the causative virus.

D

Donors must match the recipient for size. For small children, the number of size -appropriate donors is insufficient. This problem has alternatives, including: