Single lung transplantation for severe emphysema

Lung transplantation is effective therapy for patients with severe obstructive lung disease. We reviewed seven patients with severe emphysema (age, 48 +/- 5 years; forced expiratory volume in 1 second [FEV1] 0.76 +/- 0.26 liters) who received single-lung transplants (SLT) at our institution between August 1989 and September 1990. Studies to assess the adequacy of cardiac function before transplantation showed moderately reduced right ventricular function (by multiple gated acquisition, 34 +/- 6%), moderately elevated pulmonary artery pressure (25 +/- 3 mm Hg), and normal left ventricular function (by multiple gated acquisition 65% +/- 12%) and coronary arteriograms. Time on the waiting list before transplantation was reduced compared with heart-lung transplant (HLT) recipients (waiting time, 2.9 +/- 1.5 months for SLT, 9.6 +/- 10.2 months for HLT). Six of the SLT recipients are currently alive (after transplantation interval, 17 +/- 5 months); the remaining recipient died of pulmonary embolism 21 days after SLT. Number of ventilator days, intensive care unit days, and days to hospital discharge after transplantation did not differ significantly from HLT recipients. Cardiopulmonary bypass was necessary in four SLT recipients. Pulmonary function was markedly improved after SLT (FEV1, 1.78 +/- 0.73 L/min after SLT versus 0.75 +/- 0.3 L/min before SLT; p less than 0.01), and functional status is correspondingly improved.

CONCLUSIONS

SLT constitutes effective therapy for patients with severe emphysema, including those with moderate reduction of right ventricular function; and SLT offers distinct advantages over HLT, including decreased waiting time before transplantation, improved donor organ utilization, and less frequent need for cardiopulmonary bypass.

Heart-lung transplantation for cystic fibrosis

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Cardiac transplants. Heart and heart-lung transplantation

OR nurses play an important role in organ procurement. They are responsible for gathering the necessary equipment, which includes cardioplegia supplies, normal saline, a sterile container for transplantation of the heart, a sterile retractor, vascular clamps, and dissection instruments. Orthotopic heart transplantation involves excision of the recipient heart with placement of the donor heart in a normal anatomic position. Heterotopic transplant, which consists of placing the donor heart in the right side of the chest parallel to the native heart, is rarely used. In heart-lung transplantation procedures, attention is given to the removal of the heart and each lung separately to prevent injury to the vagus, phrenic, and laryngeal nerves.

Whence the lungs? A study to assess suitability of donor lungs for transplantation

Efforts at clinical lung transplantation have been hampered by an insufficient donor pool. To estimate the number of potential suitable lung donors, we conducted a UNOS-sponsored survey of organ procurement organizations and collected data with respect to possible lung donation from human cardiac donors. Contact with OPOs was made by telephone after cardiac donors were identified by UNOS. Of 150 cardiac donors, 7 were utilized for lung or heart-lung transplantation. By our criteria, however, 47 additional donors had lungs that may have been suitable for transplantation but were not utilized, and frequently were not offered for transplantation for a variety of reasons. This survey implies that approximately 25% of cardiac donors likely have lungs that may be suitable for transplantation.

[Reperfusion injury after heart-lung transplantation--OP41483-alpha-CD (prostaglandin I2 analogue) as a preventive for the reperfusion injury, especially the oxygen derived free radicals]

In clinical heart-lung transplantation, reperfusion injury is a serious problem. This study was undertaken to evaluate the preventive effect of OP 41483-alpha-CD (OP) as a stable prostaglandin I2 analogue on the reperfusion injury, especially oxygen derived free radicals after the heart-lung transplantation. The heart-lung transplantation was performed according to the Schäefers' method. Explanted heart-lung block was immersed and preserved in the UW solution for just 4 hours at 4 degrees C. In the OP group, OP was administered to the grafts through the pulmonary artery for 25 minutes before and after the reperfusion. No spin adducts were detected in the plasma before harvest of the graft by ESR spectroscopy. But after the onset of reperfusion, free radical in the plasma could be detected. Those signals were 2.007 of the g factor and 15.5 G of the hyperfine splitting constancy (aN). These findings suggested that the free radical detected in the blood of this model was hydroxyl radical. Max dp/dt, left ventricular pressure and cardiac index were higher in the OP group than in the control group after reperfusion, but there was no difference in the left ventricular end-diastolic pressure between two groups. And adenosine triphosphate contents of the myocardial cell was higher in the OP group than in the control group at 60 min after the onset of reperfusion. Oxygenation by the graft's lung was better in the OP group than in the control group after reperfusion. Radical intensities of the plasma by ESR after reperfusion were significantly higher in the pulmonary vein than in the coronary sinus. When OP was administered, radical intensities in the lung and the plasma of the pulmonary vein were significantly lower in the OP group than in the control group. Thiobarbituric acid-reactive substances increased gradually, in two groups with less increase in the OP group. These show that the free radicals, especially.OH generated from the transplanted heart and lung contribute to the reperfusion injury. The platelet counts in the systemic blood, furthermore, did not change appreciably in the OP group, but decreased rapidly in the control group. Probably the microemboli formation was partially inhibited by the administration of OP. Following the onset reperfusion, the free radicals attack the cell membranes and cause the cell damage. When OP was administered through the pulmonary artery, less free radicals were generated in the lung, and the microemboli were possibly inhibited by platelets anti-agglutination. OP administration is useful in the heart-lung transplantation.

Future horizons of lung preservation by application of a platelet-activating factor antagonist compared with current clinical standards. Euro-Collins flush perfusion versus donor core cooling

With the introduction of platelet-activating factor antagonists, a direct inhibition of ischemia-induced reperfusion injury can be achieved by prevention of platelet activation, reduction of microvascular leakage, and platelet-activating factor-induced bronchoconstriction. At present, two preservation methods are established for clinical lung preservation: (1) donor core cooling by extracorporeal circulation and (2) pulmonary artery flush with Euro-Collins solution and prostacyclin. We compared the quality of organ preservation obtained with these methods to the application of a platelet-activating factor antagonist (WEB 2170; 0.3 mg/kg) for the donor, perfusion solution, and throughout the first 6 hours of reperfusion in combination with prostacyclin (20 ng/kg/min) and Euro-Collins solution (60 ml/kg). Eighteen heterotopic heart and orthotopic left lung transplants were performed in three groups of six dogs each after 6 hours of cold ischemia (group I, donor core cooling; group II, Euro-Collins flush and prostacyclin; group III, Euro-Collins flush, prostacyclin, and WEB 2170). Myocardial preservation was achieved with St. Thomas' Hospital solution (20 ml/kg) in all groups. After transplantation, cardiorespiratory function was assessed at an inspired oxygen fraction of 0.4. After transplantation, superior results were observed in group III, as expressed by significantly improved oxygenation, while cardiac output and pulmonary artery pressures were similar in all groups. We concluded that the use of the platelet-activating factor antagonist WEB 2170 resulted in better lung preservation than current clinical standards.

Heart-lung transplantation in situs inversus. A case report in a patient with Kartagener's syndrome

After a long history of recurrent chronic pulmonary infections in a 25-year-old woman with Kartagener's syndrome, a heart-lung transplantation was performed. A modified surgical procedure was needed to perform transplantation because of the presence of a situs inversus, which is usually associated with bronchiectasis and sinusitis in this congenital syndrome. A large single atrium was created with both the right and left recipient atria used to facilitate anastomosis with the donor's right atrium. The patient was discharged after resolution of early ventilatory complications and is in good condition 8 months after transplantation.

Detection of inspiratory resistive loads by heart-lung transplant recipients

Human heart-lung transplantation recipients (HL) are models for the effects of selective lower respiratory tract denervation. We used a series resistor to examine thresholds of inspiratory flow resistance perception among 16 HL in comparison with 15 normal control subjects (C) and 12 heart transplant recipients (H). HL and C were closely age matched. H subjects were older and had mildly reduced lung volumes compared with the other groups. The perception threshold was defined as the added resistance (delta R) detected by subjects at 50% of random, blinded presentations. These delta R were subsequently expressed as a fraction of the airway resistance of the subject and baseline resistance of the apparatus (delta R/Raw + Rapparatus), otherwise known as the Weber fraction. The mean +/- SEM Weber fractions were nearly identical for HL and C (0.32 +/- 0.05 versus 0.34 +/- 0.05, respectively). The Weber fraction of H (0.74 +/- 0.17) was significantly greater than those of both other groups (p less than 0.05 by Kruskal-Wallis test). We conclude that lower respiratory tract afferents do not play a significant role in the perception of inspiratory resistive loads. The finding of an abnormally high Weber fraction in the heart transplant population remains unexplained but may be a function of age or restrictive pulmonary defects.

Difference of rejection between heart and heart-lung transplantation in rats: flowcytometric analysis of graft infiltrating lymphocyte subsets

Reported clinical and experimental observations indicate that heart grafts in combined heart-lung transplantation are less frequently rejected than heart grafts transplanted alone. In order to elucidate the mechanism of this difference, twenty-eight inbred male Lewis rats receiving heterotopic allografts from inbred male Fisher rats were evaluated for surface markers of graft infiltrating lymphocytes (GIL) and peripheral blood lymphocytes (PBL) using flowcytometry. Monoclonal antibodies investigated in this study were W3/25 (anti-helper T lymphocyte), OX8 (anti-suppressor/cytotoxic T lymphocyte), OX39 (anti-interleukin 2 receptor), and OX6 (anti-MHC class II antigen). In the acute study, a heart transplanted group (n = 7) and a heart-lung transplanted group (n = 7) without immunosuppression were studied. In the chronic study, cyclosporine (10 mg/kg/day i.m.) were administered in the heart transplanted group (n = 7) and the heart-lung transplanted group (n = 7). Both in the acute and chronic studies, the proportion of W3/25 positive cells in GIL of heart grafts of the heart transplanted group was significantly higher than that of heart grafts and lung grafts of the heart-lung transplanted group. OX8 positive cell proportion in GIL of heart grafts and lung grafts of the heart-lung transplanted group were significantly higher than that of heart grafts of the heart transplanted group. These results lead us to speculate that suppressor T lymphocytes are an important distinguishing factor in the rejection processes of heart allografts and heart-lung allografts as observed in clinical experience.

Primary Pulmonary Hypertension

Primary pulmonary hypertension (PPH) is a rare disease of unknown aetiology which typically results in right heart failure and death within several years of the onset of symptoms. While there is no cure for PPH, several pharmacological and surgical approaches to treatment have been developed over the past decade which proved useful in a significant proportion of patients. In particular, vasodilator therapy may produce sustained haemodynamic and symptomatic improvement in up to approximately two-thirds of patients; in the remaining patients, vasodilators may either produce no benefit or result in deterioration. The calcium channel blocking agents are the most widely used oral vasodilators; continuous intravenous infusions of epoprostenol (prostacyclin; prostaglandin I2) have been used in some patients who are refractory to oral therapy, particularly as a bridge to transplantation. While combined heart-lung transplantation has been considered the surgical procedure of choice for severe pulmonary hypertension, single lung transplantation has been performed successfully in a small number of patients, and may be the preferred approach in patients with reasonably preserved right heart function.

Cystic fibrosis in adolescents and adults. The coming of age of cystic fibrosis

Cystic fibrosis (CF) is the commonest, fatal, autosomal recessive disorder and is associated with lung sepsis, pancreatic failure and elevated sweat electrolytes. The CF gene on chromosome 7 encodes a protein identified as CF transmembrane conductance regulator (CFTR) which regulates chloride ion transport in epithelial cell membranes. Almost 100 mutations have been identified in this gene which cause defective chloride-channel control. Recently, this abnormality has been reversed in affected CF cells in vitro by retrovirus-mediated transfer of a normal gene. Fifty years ago, most cases died in childhood, but now up to 80% reach adulthood. Chronic lung sepsis is the principal cause of death, and intensive antibiotic therapy with chest physiotherapy is used to control this. Advanced lung disease can be successfully treated by heart-lung transplantation. Nebulised recombinant DNase and antineutrophil elastase agents such as alpha-1-antitrypsin and secretory leucoprotease inhibitor are potentially promising new therapies. Pancreatic insufficiency is managed by high-calorie diets and enteric coated enzyme supplements. Other prominent gastrointestinal complications include meconium ileus equivalent, biliary cirrhosis and cholelithiasis. Specially dedicated CF centres have led to improved survival rates and allow experienced staff to treat the many complications of CF while promoting research in this multisystem disorder.

Cardiac function after domino-donor heart transplantation

A major limitation in cardiac transplantation is donor availability. A possible way to increase the supply of donor hearts is to use explanted hearts from patients undergoing heart-lung transplantation for primary lung disease. One potential advantage of this approach, termed domino-donor transplantation, is the existence of a donor right ventricle already adapted to pulmonary hypertension, which would therefore theoretically decrease the likelihood of acute donor right heart failure in recipients with preexisting elevation of pulmonary vascular resistance. Potential disadvantages include graft failure secondary to chronic effects of pulmonary hypertension on the right ventricle, arrhythmia and infections. Seven domino-donor transplants were performed at Stanford University Hospital; graft and patient survival to date are 100% at a mean follow-up of 20 months (range 1 to 26). Infection and rejection rates have been comparable to those of the current Stanford experience for conventional orthotopic transplantation. Right ventricular function and size have either improved or remained unchanged in all patients after transplantation. Transient early postoperative donor right ventricular dilation, a characteristic adaptive response seen in nondomino transplants, occurred in 4 patients with pulmonary hypertension before surgery. These data indicate that, with adequate assessment before surgery, domino-donor cardiac transplantation is an appropriate means of augmenting the donor pool.

Assessment of pulmonary vascular injury

The assessment of pulmonary injury in experimental and clinical situations remains a challenge. A method of quantifying pulmonary vascular aberrations in animal models and human clinical situations is described. A multiple-indicator dilution technique is employed to assess changes in lung capillary permeability--surface area product, extravascular lung water, and cardiac output. A mixture of 51Cr-RBC, 125I-albumin, tritiated water, and [14C]urea is injected into a central vein. Samples of the subject's blood are collected at timed intervals and counted for beta and gamma activity. Time concentration curves for each isotope are constructed. The capillary permeability--surface area product is calculated from the extraction pattern for [14C]urea. Extravascular lung water is calculated from the extraction pattern of tritiated water and cardiac output is calculated from the inverse of the area under the 51Cr curve. Normal reference curves are constructed for all subject groups. Significant changes occurred in capillary-permeability surface area product and extravascular lung water in various experimental models producing injury, in the patient population manifesting adult respiratory distress syndrome, and in those patients who have received cardiopulmonary transplants. The multiple-indicator dilution technique represents a sensitive tool for evaluating pulmonary vascular changes.

Pseudoaneurysm of the aorta after heart-lung transplantation: diagnosis by color flow Doppler mapping

Five months after heart-lung transplantation for treatment of end-stage cystic fibrosis, a 14-year-old girl had a swelling over the manubrium that was identified as a pseudoaneurysm at the aortic anastomotic site by means of cross-sectional echocardiography with color flow Doppler mapping. The diagnosis was confirmed at operation, despite which she died. Biopsy material taken during the operation revealed chronic sternal osteomyelitis caused by Pseudomonas aeruginosa. Disruption of the aortic anastomosis by infection may be a major complication of heart-lung transplantation for treatment of cystic fibrosis.

Semiquantitative measurement of cytomegalovirus DNA in lung and heart-lung transplant patients by in vitro DNA amplification

We report the cases of two lung transplant recipients (one heart-lung and one single lung) who eventually developed cytomegalovirus (CMV) pneumonitis after documentation of increasing CMV DNA titers in sequential bronchoalveolar lavage (BAL) specimens by polymerase chain reaction (PCR) amplification. To our knowledge, this is the first report that semiquantitation of PCR-amplified DNA can detect an increase in CMV DNA titer in BAL specimens prior to the onset of clinical symptoms or detection of infection by traditional techniques in lung transplant patients. The results obtained in these two cases suggest that DNA titer measurement on sequential BAL samples may differentiate latency from active viral replication and, thus, provide an opportunity for clinical intervention before the development of overt clinical symptoms.

Bronchial fistula to the mediastinum in a heart-lung transplant patient

We present a case of heart-lung transplantation complicated by bronchial perforation as the cause or consequence of prolonged lung infection. Periodic bronchoscopic and radiological follow-up showed resolution of the condition following adequate antibiotic and physiotherapeutic treatment.

Organ preservation for heart-lung and lung transplantation

One of the most important restrictions in the field of heart-lung- and lung-transplantation remains the limited ischemic tolerance of the lung. From December 1987 through February 1991, 44 patients underwent either single-, double-, or heart-lung-transplantation. All organs were harvested in multiorgan procedures. For the first 4 patients core cooling of the donor was used. For the rest pulmonary artery flush with modified Euro-Collins solution and prostacyclin was employed. Ischemia time varied from 3-6.5 hours (mean 241; 176-390 minutes). Hearts were arrested with St. Thomas cardioplegia. Oxygenation was satisfactory at 24 hours: p O2 greater than 100 mmHg, FI O2 less than 30% oxygen. It is concluded that for lung preservation modified Euro-Collins solution and prostacyclin for flush perfusion of the pulmonary artery will result in excellent lung function early postoperatively with ischemic times up to 6.5 hours. This method seems advantageous compared to others due to the limited surgical and instrumental needs.

Single-lung transplantation for pulmonary hypertension. Three-month hemodynamic follow-up

BACKGROUND

Shorter waiting times, relative technical simplicity, and satisfactory application to a broad spectrum of patients has made single-lung transplantation an attractive option in the treatment of patients with end-stage pulmonary hypertension.

METHODS AND RESULTS

Seven patients with pulmonary hypertension underwent single-lung transplantation. Simultaneous closure of associated atrial septal defects was accomplished in two patients. Despite severely compromised pretransplant right ventricular function in all patients, there was no early or late mortality. Right ventricular functional recovery as characterized by hemodynamic assessment before and at a mean of 13 weeks posttransplant was nearly uniform and characterized by a drop in 1) pulmonary arterial systolic pressure from 92 +/- 7 mm Hg to 29 +/- 6 mm Hg (p = 0.001), 2) central venous pressure from 10 +/- 6 mm Hg to 1 +/- 2 mm Hg (p = 0.02), and 3) pulmonary vascular resistance index from 1,924 +/- 663 to 232 +/- 73 dyne.sec.cm-9 (p = 0.001). Radionuclide ventriculography before and at a mean of 17 weeks posttransplant documented a significant (p = 0.006) increase in right ventricular ejection fraction from 22 +/- 15% to 51 +/- 11%. Quantitative pulmonary perfusion scintigraphy at a mean of 17 weeks posttransplant demonstrated a significant (p = 0.001) increase in perfusion to the transplanted lung from 56 +/- 6% to 89 +/- 7%. There was a concomitant, slight but significant (p = 0.004) decrease in ventilation to the transplanted side from 56 +/- 6% to 49 +/- 8%. After transplantation, all patients returned to New York Heart Association functional class I or II from their preoperative levels of class III or IV.

CONCLUSIONS

These early follow-up data cautiously support the option of single-lung transplantation in patients with pulmonary hypertension, although long-term durability of these hemodynamic changes deserves documentation before widespread application.

Lung transplant pathology. A comparative study of pulmonary acute rejection and cytomegaloviral infection

This article describes a comparative study performed to determine the histologic features of pulmonary rejection and cytomegaloviral (CMV) infection following lung transplantation. Rejection was defined clinically by findings of new pulmonary symptoms or radiographic changes or decreased oxygenation in the absence of documented infection in patients who were treated for rejection and improved. These patients also had negative CMV cultures. CMV infection was studied in a group of non-lung and non-bone marrow transplant patients and was defined by the presence of characteristic nuclear inclusions in lung biopsies. Ten rejection biopsies and nine CMV biopsies were examined. No histologic feature was unique to rejection, however; perivascular lymphocytic infiltrates occurred more frequently and more intensely in rejection than in CMV infection (p = 0.0029). Endothelialitis also occurred more frequently in rejection (p = 0.0331), but it was always seen in association with perivascular lymphocytic inflammation. In rejection, the inflammatory infiltrate was primarily perivascular, with extension into the interstitium in several cases. In contrast, CMV infection was characterized predominantly by interstitial inflammation with involvement of associated vessels. We conclude that although overlapping features are present in both processes, pulmonary rejection can be distinguished from CMV infection on the basis of histology.