Standardized exercise oximetry predicts postpneumonectomy outcome

BACKGROUND

We have developed a safe, simple, and easily performed standardized exercise oximetry outpatient test to assess patients undergoing lung resections. We studied its ability to predict outcome after pneumonectomy in 46 consecutive patients over a 5-year period.

METHODS

Room air oximetry is initially performed at rest. The patient then begins to exercise on a stair-stepper apparatus (Stamina Stepper), which provides uniform resistance to stepping. Oxygen saturation values are noted at 10, 20, and 30 steps, equivalent to climbing three flights of stairs. Group 1 consisted of the patients who either had a resting saturation less than 90%, or desaturation greater than or equal to 4% during exercise. Group 2 consisted of all patients who had a preoperative forced expiratory volume in 1 second of 60% or less. Group 3 consisted of all patients who had a predicted postoperative forced expiratory volume in 1 second of 40% or less. Group 4 consisted of patients who had a predicted postoperative diffusing capacity of 40% or less.

RESULTS

There were four deaths (8.6%), 12 patients (26%) remained in the intensive care unit 4 or more days, and 11 patients (23%) suffered major morbidity. Desaturation during exercise (group 1) significantly predicted longer intensive care unit stay (p = 0.0002) and incidence of major morbidity (p < 0.0001). Groups 2, 3, and 4 were not significantly predictive of either longer intensive care unit stay or major morbidity.

CONCLUSIONS

Standardized exercise oximetry performed in the outpatient facility is highly predictive of major morbidity and prolonged intensive care unit stay after pneumonectomy.

Dose-related reversal of acute lung rejection by aerosolized cyclosporine

This study evaluated the effectiveness of aerosolized cyclosporine as rescue therapy for refractory acute rejection in lung-transplant patients that is unresponsive to conventional therapy. Over 2 yr, nine allograft recipients with histologic evidence of persistent acute rejection and worsening pulmonary function were enrolled. Twenty-two patients with similar degrees of unremitting rejection served as historical controls. Aerosolization of cyclosporin A (300 mg in 4.8 ml propylene glycol) using an AeroTech II jet nebulizer was instituted daily for 12 consecutive days followed by a maintenance regimen of 3 d/wk. Cyclosporine and tacrolimus blood and plasma levels were maintained within therapeutic ranges throughout this trial. Efficacy was assessed by histologic grade of rejection, interleukin-6 (IL-6) mRNA expression by graft bronchoalveolar lavage cells, and pulmonary function testing before and during cyclosporine therapy. In seven patients, results were correlated to deposition of cyclosporine aerosol in the allograft(s) as measured by radioisotopic techniques. At a mean of 37 d after initiation of aerosolized cyclosporine, graft histology improved in eight of the nine patients. Cellular IL-6 mRNA expression decreased significantly in seven patients (mean IL-6/actin +/- SD, 40.96 +/- 118 versus 0.33 +/- 0.57 [p = 0.038]). Pulmonary function (FEV1), which had decreased posttransplant (over a mean of 347 d of observation) from a best value of 1.98 +/- 0.8 L to 1.59 +/- 0.6 L (p = 0.0077), improved over time (152 d) to a posttransplant value of 1.90 +/- 0.8 (p = 0.025). In the control subjects, FEV1 inexorably declined over a comparable period of observation (best posttransplant value 2.36 +/- 0.86 to 1.32 +/- 0.53, p < 0.0001). There was a strong correlation between cyclosporine deposition in the allograft and improvement in FEV1 (r = 0.900, p < 0.01). Fewer cycles of pulsed corticosteroids (1.4 +/- 0.9 versus 0.2 +/- 0.4, p = 0.011) and anti-thymocyte globulin 0.8 +/- 0.4 versus 0, p = 0.018) and reduced doses of oral prednisone (10.8 +/- 3.1 versus 6.1 +/- 4.2 mg/d, p = 0.026) were observed during treatment with aerosolized cyclosporine. Episodes of pneumonia also were reduced significantly during aerosol therapy (2.6 versus 0.95 episodes/100 d, p = 0.029). Nephrotoxicity and hepatotoxicity did not occur, and no patients withdrew from the study. Aerosolized cyclosporine appears to be safe and effective therapy for refractory acute rejection, but confirmation by a larger, randomized trial is necessary. The correlation observed between deposition of cyclosporine aerosol and physiologic improvement of lung function suggests that there is a dose-response relationship between the concentration of cyclosporine in the allograft and immunologic tolerance.

Influence of panel-reactive antibody on survival and rejection after lung transplantation

BACKGROUND

Panel-reactive antibody (PRA) is commonly used before thoracic organ transplantation to estimate a potential recipient's degree of humoral sensitization.

METHODS

To assess the influence of an elevated PRA on survival and the incidence of rejection in pulmonary transplantation, the records of 247 patients that underwent single or double lung transplantation were reviewed.

RESULTS

Twenty-one of 247 patients (8.5%) had PRA values greater than 10%. Survival of this population was not significantly different from that of patients with low PRA levels: 74% (low PRA) vs 65% (elevated PRA) at 1 year and 58% in both groups at 3 years. The acute rejection rates (episodes/first 100 days) for the elevated and low PRA groups were 2.1 and 1.9, respectively (p = NS). Obliterative bronchiolitis developed in 38.9% of the high and 31.2% of the low PRA groups (p = NS). Six of 247 patients had a retrospective positive lymphocytotoxic cross-match result; three had PRA values greater than 10%. Patients with a positive cross-match result experienced similar survival and incidence of rejection as the remainder of the population. Among 957 patients evaluated for lung transplantation, 16 (1.7%) had a PRA (with dithiothreitol) greater than 15%. All had a history of pregnancy, blood transfusion, connective tissue disease, or previous transplantation.

CONCLUSIONS

Humoral sensitization is uncommon in the lung transplantation population. A modestly elevated PRA does not predict survival or the development of acute rejection or bronchiolitis obliterans. PRA testing before lung transplantation should be reserved for those patients with specific risk factors for humoral sensitization.

Reperfusion injury in single-lung transplant recipients with pulmonary hypertension and emphysema

BACKGROUND

The early postoperative course of single-lung transplant recipients depends on the recipient's underlying lung pathophysiology and the degree of ischemic-reperfusion injury. We examined the effect of pulmonary hemodynamics and preoperative diagnosis on early allograft function and the effects of pulmonary hemodynamics, allograft blood flow, and chest radiographs on length of mechanical ventilation and intensive care unit length of stay.

METHODS

We retrospectively collected data on 30 single-lung transplant recipients, 15 each with pretransplantation pulmonary hypertension and emphysema. Blood flow to the allografts was quantitated by perfusion scans obtained on the first postoperative day. Chest radiographs were graded for reperfusion injury. Pulmonary and hemodynamic data, gas exchange parameters, duration of mechanical ventilation, and intensive care unit stay were recorded.

RESULTS

Patients with pulmonary hypertension had a prolonged intensive care unit stay compared with emphysema patients, but pulmonary artery pressures were not quantitatively related to duration of ventilation during the intensive care unit stay. There was no difference in the severity of allograft infiltrate between the emphysema and pulmonary hypertensive patients. The day 1 chest radiograph score was highly predictive of an intensive care unit stay of > or = 7 days, although the threshold score of those with pulmonary hypertension was significantly lower than in emphysema patients. Allograft blood flow and pulmonary hypertension were not contributors to early graft dysfunction. Allograft perfusion decreased with increasing radiographically demonstrated infiltrate in those with emphysema but not in those with pulmonary hypertension.

CONCLUSIONS

Elevated allograft blood flow and pressures do not exacerbate radiographically confirmed reperfusion injury. Reperfusion injury is the major cause of early respiratory morbidity after single-lung transplantation. Allograft perfusion in emphysema patients decreases in response to reperfusion injury, but pulmonary hypertension patients remain almost entirely dependent on allograft function, even with severe chest radiograph scores. This may be an important mechanism by which single-lung transplant recipients with emphysema, unlike those with pulmonary hypertension, are able to mitigate the degree of respiratory impairment associated with reperfusion injury.

Wedge resection versus lobectomy for stage I (T1 N0 M0) non-small-cell lung cancer

BACKGROUND

The role of nonanatomic wedge resection in the management of stage I (T1 N0 M0) non-small-cell lung cancer continues to be debated against the present gold standard of care--anatomic lobectomy.

METHODS

We analyzed the results of 219 consecutive patients with pathologic stage I (T1 N0 M0) non-small-cell lung cancer who underwent open wedge resection (n = 42), video-assisted wedge resection (n = 60), and lobectomy (n = 117) to assess morbidity, recurrence, and survival differences between these approaches.

RESULTS

There were no differences among the three groups with regard to histologic tumor type. Analysis demonstrated the wedge resection groups to be significantly older and to have reduced pulmonary function despite a higher incidence of treatment for chronic obstructive pulmonary disease when compared with patients having lobectomy. The mean hospital stay was significantly less in the wedge resection groups. There were no operative deaths among patients having wedge resection; however, a 3% operative mortality occurred among patients having lobectomy (p = 0.20). Kaplan-Meier survival curves were nearly identical at 1 year (open wedge resection, 94%; video-assisted wedge resection, 95%; lobectomy, 91%). At 5 years survival was 58% for patients having open wedge resection, 65% for those having video-assisted wedge resection, and 70% for those having lobectomy. Log rank testing demonstrated significant differences between the survival curves during the 5-year period of study (p = 0.02). This difference was a result of a significantly greater non-cancer-related death rate by 5 years among patients having wedge resection (38% vs 18% for those having lobectomy; p = 0.014).

CONCLUSION

Wedge resection, done by open thoracotomy or video-assisted techniques, appears to be a viable "compromise" surgical treatment of stage I (T1 N0 M0) non-small-cell lung cancer for patients with cardiopulmonary physiologic impairment. Because of the increased risk for local recurrence, anatomic lobectomy remains the surgical treatment of choice for patients with stage I non-small-cell lung cancer who have adequate physiologic reserve.

Treatment of refractory acute allograft rejection with aerosolized cyclosporine in lung transplant recipients

Lung transplant recipients who have persistent acute cellular rejection are at increased risk for the development of chronic rejection, the leading cause of reduced long-term survival. This study evaluated the use of aerosolized cyclosporine as rescue therapy for unremitting acute rejection. Between June 1993 and March 1996, 18 patients with rejection that failed to resolve after therapy with pulse steroids and antilymphocyte globulin were enrolled in the study. Aerosolized cyclosporine A (300 mg) treatment was initiated for 10 consecutive days followed by a maintenance regimen of 3 days per week. Efficacy was assessed by graft histologic and pulmonary function testing. With the use of linear regression, results in these patients were compared with those in 23 control patients, matched for histologic acute rejection, who had continued to receive conventional rescue therapy. Two patients were unable to tolerate the treatments and were withdrawn from the study. Significant improvement in histologic rejection occurred in 14 of the remaining 16 patients after a mean of 37 days of aerosolized cyclosporine therapy. Measures of forced vital capacity and forced expiratory volume in 1 second (change in percent predicted/100 days plus or minus the standard error) increased over time in the treated patients whereas the condition of control patients declined despite repeated attempts at conventional rescue (forced vital capacity, aerosolized cyclosporine group, 4.6 +/- 2.9 vs control group -8.1 +/- 1.9, p = 0.001; forced expiratory volume in 1 second, aerosolized cyclosporine group, 2.1 +/- 4.4 vs control group -9.8 +/- 2.6, p = 0.043). Renal and hepatic toxicity during cyclosporine therapy was not observed. The incidence of acute histologic rejection (> or = A2) decreased from 2.49 +/- 0.68 episodes/100 days before aerosolized cyclosporine therapy to 0.72 +/- 0.3 episodes/100 days (p < 0.05). In summary, aerosolized cyclosporine is a safe and effective therapy for acute rejection that has failed to improve with conventional treatment.

Structure of the conserved GTPase domain of the signal recognition particle

The signal-recognition particle (SRP) and its receptor (SR) function in the co-translational targeting of nascent protein-ribosome complexes to the membrane translocation apparatus. The SRP protein subunit (termed Ffh in bacteria) that recognizes the signal sequence of nascent polypeptides is a GTPase, as is the SR-alpha subunit (termed FtsY). Ffh and FtsY interact directly, each stimulating the GTP hydrolysis activity of the other. The sequence of Ffh suggests three domains: an amino-terminal N domain of unknown function, a central GTPase G domain, and a methionine-rich M domain that binds both SRP RNA and signal peptides. Sequence conservation suggests that structurally similar N and G domains are present in FtsY. Here we report the structure of the nucleotide-free form of the NG fragment of Ffh. Consistent with a role for apo Ffh in protein targeting, the side chains of the empty active-site pocket form a tight network of interactions which may stabilize the nucleotide-free protein. The structural relationship between the two domains suggests that the N domain senses or controls the nucleotide occupancy of the GTPase domain. A structural subdomain unique to these evolutionarily conserved GTPases constitutes them as a distinct subfamily in the GTPase superfamily.

Lung and heart-lung transplantation at the University of Pittsburgh

The application of lung transplantation as a treatment modality for patients with severe pulmonary disease has changed dramatically since its inception. At the University of Pittsburgh, the criteria for recipient selection continues to evolve and, in an effort to maximize scarce donor organs, the criteria for donor lung acceptance have been extended. Patient survival during the first 3 years after transplantation continues to improve but longer term survival is limited by infectious complications and chronic rejection. In early studies, the utilization of cyclosporine delivered directly to the lungs via aerosol has resulted in dramatic improvement in pulmonary function in recipients with immune mediated allograft injury and has allowed a reduction in systemic immunosuppression. We are hopeful that interventions such as this will result in prolongation of patient survival with less toxicity.

Spirometry values in stable lung transplant recipients

To clarify the usefulness of spirometry to assess the function of the lung allograft post-transplant, we retrospectively reviewed 351 sequential spirometry measurements performed by 65 healthy recipients after the 80th postoperative day when the clinical evaluation and fiberoptic bronchoscopy with transbronchial biopsies and bronchoalveolar lavage excluded significant rejection or infection in the allograft. The mean coefficients of variation (CV) and significant values for change (SC) for the FVC, FEV1, and FEF25-75% were calculated according to the type of transplant procedure (heart-lung and double-lung [HL-DL] versus single-lung [SL]), and to the time after transplant when the spirometry measurements were obtained < or = 1 yr versus > 1 yr). The SC for the FVC decreased with time after transplantation for both HL-DL (< or = 1 yr: 17% versus > 1 yr: 7%) and SL recipients (< or = 1 yr: 13% versus > 1 yr: 8%). The higher degree of variability within the first year was primarily due to increasing values especially in the HL-DL recipients. The SC for the FEV1 also decreased over time for HL-DL recipients (< or = 1 yr: 18% versus > 1 yr: 9%) but was similar for SL recipients at both intervals (13%). Our results suggest that decreases of > or = 11% in FVC or 12% in FEV1 in HL-DL recipients and > or = 12% in FVC or 13% in FEV1 for SL recipients indicate a significant decrease in allograft function that may be due to infection or rejection.

Changes in lung volume and volume of emphysema after unilateral lung reduction surgery: analysis with CT lung densitometry

PURPOSE

To evaluate changes in volume of the lungs and volume of emphysema after unilateral lung reduction surgery (ULRS) by using computed tomographic (CT) lung densitometry.

MATERIALS AND METHODS

Twenty-eight patients underwent CT before and 3 months after ULRS. With use of a density mask software program and a three-dimensional graphics workstation, CT scans were analyzed to define the volume of the lungs and the volume of emphysema. Pre- and postoperative mean CT numbers were determined.

RESULTS

After ULRS, the surgically reduced lung volume decreased 22%, and the intact opposite lung volume increased 4%. Emphysema in the surgically reduced lung decreased 14% and was unchanged in the intact opposite lung. Mean CT numbers in the surgically reduced lung increased 26 HU but were unchanged in the intact opposite lung.

CONCLUSION

The effects of ULRS on each lung can be evaluated by using CT lung densitometry and a three-dimensional graphics workstation. ULRS reduces emphysema and lung volume in the surgically reduced lung without statistically significant worsening of contralateral emphysema at 3 months.

Successful management of secondary aortoesophageal fistula

Aortoesophageal fistula is a rare complication after thoracic aortic aneurysm repair. Six previously reported cases of aortoesophageal fistula management have been uniformly fatal. We present our successful management and review the literature of this topic.

NMR studies of the most conserved RNA domain of the mammalian signal recognition particle (SRP)

Mammalian signal recognition particle (SRP) and its homologues exhibit a phylogenetically conserved RNA domain, whose predicted secondary structure exhibits a hairpin motif with two bulged regions. Two RNA fragments comprising one (24 nt) or two (43 nt) of the conserved bulges were studied. Each fragment binds specifically to the domain of the Escherichia coli homologue of the SRP54 protein, which is involved in signal sequence recognition. The SRP RNA fragments exhibited a pronounced structural stabilization in the presence of Mg2+. Assignments of all base, H1', H2', and most imino proton resonances in the presence of Mg2+ were obtained for the 24mer RNA via NOE spectroscopy and correlated homonuclear NMR methods. 2D NOE patterns permitted a coarse structural description, revealing a relatively compact A-type geometry for the 24mer without any indications of looped-out nucleotides, syn-oriented bases, or base triplets. The GGAA-loop is structurally very similar to that of the GCAA tetraloop [Heus HA, Pardi A, 1991, Science 253:191-194]. Mg2+ seems to stabilize the structure of the conserved bulged region, which involves G:A and C:A mismatch pairs. Deviations from ideal A-type helicity are found for a larger region than the predicted secondary structure implies. Although no explicit assignment effort has been dedicated to the 43mer yet, striking similarity in chemical shift changes upon addition of Mg2+ allowed some structural conclusions. The bulge present in both RNA fragments exhibits a similar, pronounced flexibility in the absence of Mg2+, indicating that the additional bulge in the 43mer does not stabilize the other bulge.

Acute and chronic morbidity differences between muscle-sparing and standard lateral thoracotomies

INTRODUCTION

Opinions differ regarding differences between totally muscle-sparing thoracotomy and standard lateral thoracotomy approaches to pulmonary resection with respect to operative time, postoperative pain and morbidity, and occurrence of chronic postthoracotomy pain syndromes and subjective shoulder dysfunction.

METHODS

Three hundred thirty-five consecutive patients undergoing muscle-sparing thoracotomy (n = 148) or lateral thoracotomy (n = 187) to accomplish lobectomy for stage I lung cancer during a 40-month period were evaluated. Local rib resection was not employed, and two chest tubes were routinely used after operation in both thoracotomy groups. Epidural analgesia use was similar after operation in the two groups (muscle-sparing thoracotomy 38%, lateral thoracotomy 38%). The postoperative hospital courses and patient functional statuses at 1 year were examined.

RESULTS

Demographic analyses demonstrated no differences between groups in age, sex, or association of significant comorbid medical illness. Although the operative time required for muscle-sparing thoracotomy was shorter, there were no differences between thoracotomy approaches in any of the other primary acute postoperative variables analyzed (chest tube duration, length of hospital stay, postoperative narcotic requirements, and postoperative mortality). The frequencies of chronic pain and shoulder dysfunction assessed 1 year after operation were also similar between thoracotomy groups.

CONCLUSIONS

The relative efficacies and rates of occurrence of acute or chronic morbidity are equivalent after muscle-sparing thoracotomy and standard lateral thoracotomy. Although muscle-sparing thoracotomy may possibly be performed more expediently, it appears that the singular advantage of muscle-sparing thoracotomy over standard lateral thoracotomy involves the preservation of chest wall musculature in case rotational muscle flaps should be needed later.

Predicting ICU length of stay following single lung transplantation

STUDY OBJECTIVE

The aim was to identify potential predictors of ICU length of stay (LOS) for single lung transplant patients.

DESIGN

Retrospective chart review.

SETTING

University medical center.

PATIENTS

All single lung transplant recipients for 1992 and 1993 at our institution.

RESULTS

Data were collected from 69 patients. The median ICU LOS was 5 days, and this was highly correlated with the duration of mechanical ventilation. The mean acute physiology and chronic health evaluation (APACHE II) score was 10. Patients with pulmonary hypertension had the longest ICU LOS. Similarly, patients with a measured transpulmonary gradient of 20 mm Hg or less had a significantly shorter ICU LOS. Patients with an immediate postoperative PaO2/fraction of inspired oxygen (FIo2) ratio greater than 200 mm Hg and a flow mismatch between the two lungs of 30% or less also had a significantly shorter ICU LOS. Positive and negative predictive values for the immediate postoperative PaO2/FIo2 ratio of 200 mm Hg or less were 77% for an ICU LOS greater than 5 days, and the calculated receiver operating characteristic (ROC) curve area was 0.74.

CONCLUSION

Overall, the immediate postoperative PaO2/FIo2 ratio of 200 mm Hg or less had the best positive and negative predictive values as well as the highest ROC curve area for predicting an ICU LOS greater than 5 days.

Use of bronchial blocker to improve gas exchange in respiratory failure and differential lung disease

The use of bronchial blocker to optimize gas exchange in a patient with marked differential lung disease is reported. This technique proved to be a useful alternative in an ICU setting to independent lung ventilation.

Role of lung reduction in lung transplant candidates with pulmonary emphysema

BACKGROUND

The average waiting time for candidates for lung transplantation (LTx) with end-stage emphysema is 21 months with a 15% mortality. We hypothesized that lung reduction might offer an alternative to LTx.

METHODS

Of 95 patients with end-stage emphysema evaluated by our LTx program, 45 were accepted for both lung reduction and LTx and 35 underwent lung reduction.

RESULTS

All 35 patients survived lung reduction. Thirty patients had a follow-up of 3 months. There was a significant improvement (p < 0.05) of forced expiratory volume in 1 second (0.64 to 0.97 L), forced vital capacity (2.12 to 2.76 L), residual volume (5.62 to 4.26 L), maximum voluntary ventilation (28.1 to 38.5 L/min), 6-minute walk (904 to 1,012 feet), Borg dyspnea index (3.7 to 2.4), and arterial carbon dioxide tension (44.9 to 41.6 mm Hg). Twenty patients (66%) were removed from the LTx list due to their significant improvement (group A). Compared with the remaining 10 patients with 3 months of follow-up (group B), percent increase in forced expiratory volume in 1 second (70% in group A versus 27% in group B) and in forced vital capacity (41% group A versus 18% group B) and percent decrease in residual volume (26% group A versus 1.5% group B) were significantly better in group A (p < 0.01). Seven patients in group B were bridged to LTx; 6 of these patients (86%) had hypercarbia before lung reduction compared with 8 (40%) in group A (p < 0.05). All are alive after LTx: the forced expiratory volume in 1 second is 53% and the forced vital capacity is 64% of predicted.

CONCLUSIONS

Lung reduction is safe and effective in selected LTx candidates with end-stage emphysema and has the potential to provide an alternative to LTx. Long-term follow-up is warranted to confirm these results.

Early lung allograft function in twin recipients from the same donor: risk factor analysis

BACKGROUND

Transplantation of lung allografts from the same donor into 2 recipients ("twinning") provides an opportunity to study recipient and donor factors that influence early allograft function.

METHODS

Twenty-seven pairs of recipients were identified and evaluated using multivariate logistic regression analysis (p < 0.05). Four measures of early graft function were analyzed: alveolar-arterial gradient in the operating room, first alveolar-arterial gradient in the intensive care unit, alveolar-arterial gradient at 24 hours, and days of mechanical ventilation.

RESULTS

Analysis of the pooled data without regard to pairing showed that alveolar-arterial gradient in the operating room was influenced by donor age, length of donor hospitalization, recipient mean pulmonary artery (PA) pressure at unclamping, and transplantation of a left lung. The alveolar-arterial gradient in the intensive care unit was correlated with donor age, donor cause of death, and mean PA pressure on arrival in that unit. Only mean PA pressure remained significant at 24 hours. Days of mechanical ventilation was determined by mean PA pressure on arrival in the intensive care unit, drop in mean PA pressure during operation, and diagnosis of the recipient. In the paired analysis, receiving a left lung, recipient diagnosis (pulmonary hypertension worse than others), and need of cardiopulmonary bypass were significantly associated with immediate graft dysfunction, although these influences did not persist beyond the immediate postoperative period. Donor arterial oxygen tension and time of ischemia were not significant predictors in any analysis.

CONCLUSIONS

Immediate allograft function was associated with donor-related characteristics initially, but these lost importance over the ensuing 24 hours. Recipient PA pressure was an immediate and persisting influence. In the analysis of differences in function between the members of each pair, transplantation of the left lung, recipient diagnosis, and cardiopulmonary bypass were identified, but their influence did not persist beyond the first 6 hours.

Bronchoesophagopleural fistula after photodynamic therapy for malignant mesothelioma

A 66-year-old woman presented with a bronchoesophagopleural fistula 10 weeks after thoracic photodynamic therapy for malignant mesothelioma. This is the third reported case of an esophagopleural fistula developing subsequent to photodynamic therapy for mesothelioma. We review the literature on this topic and report our successful management of this complication.

Extracorporeal membrane oxygenation for lung transplant recipients with primary severe donor lung dysfunction

Primary severe donor lung dysfunction (DLD) is a significant complication after lung transplantation (LTx), and a high mortality is reported with conventional therapy. The purpose of this report is to review the experience of the University of Pittsburgh with extracorporeal membrane oxygenation (ECMO) for primary severe DLD after LTx. From September 1991 to May 1995, 220 LTx were performed at our center. Eight patients (8/220 = 3.6%) with severe DLD after LTx required ECMO support. The age of LTx recipients was 44 +/- 5 years (mean +/- SD); seven patients were female and one was male. Indications for LTx were: chronic obstructive pulmonary disease in four patients, bronchiectasis in two, and pulmonary hypertension in two. There were three single LTx and five bilateral LTx. The interval from LTx to institution of ECMO was 5.6 +/- 3.2 h (range 0-10 h). Three patients were supported with veno-venous (v-v) ECMO and five had veno-arterial (v-a) ECMO. The duration of ECMO support was 7.3 +/- 4.8 days (range 3-15 days). activated glotting time (ACT) was maintained between 110 and 180 s with intermittent use of heparin. Seven patients (7/8 = 87%) were successfully weaned from ECMO and six patients (6/8 = 75%) were discharged home; they are currently alive after a follow-up of 17 +/- 10.1 months. One patient died on ECMO support for refractory DLD and another died 2 months after ECMO wean from multisystem organ failure. At 6 months follow-up, forced expiratory volume in 1 s (FEV1) is 2.35 +/- 0.91 (75% +/- 17.4% predicted) and mean forced vital capacity (FVC) is 2.53 +/- 0.81 (64% +/- 14% predicted). We conclude that ECMO can be lifesaving when instituted early after primary severe DLD. The v-v ECMO support is preferred when the patient is hemodynamically stable and adequate long-term function of the allograft is anticipated.

Lung reduction surgery in chronic obstructive lung disease

In the 1960s the promise of the Brantigan lung reduction surgery was shattered when it was shown that the improvement in airway conductance drifted back towards the preoperative value over a period of 12 to 18 months. Since then there has been a marked improvement in our understanding of emphysema, its pathology, and techniques for obtaining images of the lung. In addition, reliable automated cardiopulmonary and physiologic testing, advances in critical care medicine, and new pharmacologic agents have improved patient care. Surgical techniques now allow better control of air leaks and access to anatomic regions not previously accessible. The combination of all of the above makes lung reduction surgery worth re-examining as a palliative procedure for severely symptomatic patients. Clearly, it is not a panacea but can in some cases produce dramatic improvements in symptomatology and quality of life. This article presents the available data describing potential mechanisms of improvement and clinical outcomes following lung reduction surgery. It also outlines areas that need further work, such as patient selection and surgical techniques.

Improvement in pulmonary function and elastic recoil after lung-reduction surgery for diffuse emphysema

BACKGROUND

Pulmonary function may improve after surgical resection of the most severely affected lung tissue (lung-reduction surgery) in patients with diffuse emphysema. The basic mechanisms responsible for the improvement, however, are not known.

METHODS

We studied 20 patients with diffuse emphysema before and at least three months after either a unilateral or a bilateral lung-reduction procedure. Clinical benefit was assessed by measurement of the six-minute walking distance and the transitional-dyspnea index, which is a subjective rating of the change from base line in functional impairment and the threshold for effort- and task- dependent dyspnea. Pressure-volume relations in the lungs were measured with static expiratory esophageal-balloon techniques, and right ventricular systolic function was assessed by echocardiography.

RESULTS

The patients had significant improvement in the transitional-dyspnea index after surgery (P<0.001). The mean (+/-SD) coefficient of retraction, an indicator of elastic recoil of the lung, improved (from 1.3+/-0.6 cm of water per liter before surgery to 1.8+/-0.8 after, P<0.001). Sixteen patients with increased elastic recoil had a greater increase in the distance walked in six minutes than the other four patients, in whom recoil did not increase (P=0.02). The improved lung recoil led to disproportionate decreases in residual volume as compared with total lung capacity (16 percent vs. 6 percent), but the decreases in both values were significant (P<0.001). Forced expiratory volume in one second increased (from 0.87+/-0.36 to 1.11+/-0.45 liters, P<0.001). End-expiratory esophageal pressure also decreased (P=0.002). These improvements in lung mechanics led to a decrease in arterial partial pressure of carbon dioxide form 42+/-6 to 38+/-5 mm Hg (P=0.006). Furthermore, the fractional change in right ventricular area, an indicator of systolic function, increased from 0.33+/-0.11 to 0.38+/-0.010 (P=0.02).

CONCLUSIONS

Lung-reduction surgery can produce increases in the elastic recoil of the lung in patients with diffuse emphysema, leading to short-term improvement in dyspnea and exercise tolerance.

Aerosolized cyclosporine in lung recipients with refractory chronic rejection

This study evaluated aerosolized cyclosporine as rescue therapy for lung transplant recipients with unremitting chronic rejection. Nine patients with histologic active obliterative bronchiolitis and progressively worsening airway obstruction refractory to conventional immune suppression received aerosolized cyclosporine. Improvement in rejection histology was seen in seven of nine patients. We compared the changes in the FVC and FEV1 over time using linear regression analysis in these seven histologic responders and nine historical control patients. During the pretreatment period for both the experimental and control groups, the FVC and FEV1 declined at comparable rates. After aerosolized cyclosporine there was stabilization of pulmonary function, whereas in the controls there was continued decline. Cyclosporine blood levels were less than 50 ng/ml 24 h after an aerosolized dose of 300 mg in five patients receiving oral tacrolimus. Nephrotoxicity, hepatotoxicity, and a greater than expected rate of infection was not observed. This study suggests that aerosolized cyclosporine is safe and may be effective therapy for refractory chronic rejection in lung transplant recipients.

Laparoscopic fundoplication: a natural extension for the thoracic surgeon

BACKGROUND

Thoracic surgeons have historically played a significant role in surgical treatment of benign esophageal disorders. With the advent of video-assisted thoracic surgical techniques, chest surgeons have also become adept at minimally invasive procedures. Thus, it seems appropriate that thoracic surgeons participate in minimally invasive antireflux operations, such as laparoscopic Nissen fundoplication.

METHODS

From February 1993 to May 1995, 66 patients (32 male, 34 female) with a mean age of 45.5 years (range, 15 to 82 years) underwent a laparoscopic fundoplication. Gastroesophageal reflux disease was diagnosed on the basis of history and endoscopically documented esophagitis or abnormal esophageal pH testing or both. There were 45 type I, 3 type II, and 7 type III hiatal hernias. Eleven patients had gastroesophageal reflux disease with no hernia.

RESULTS

Conversion to laparotomy occurred in 6 patients (9%) due to bleeding in 2 patients, inability to expose the gastroesophageal junction in 3, and gastric laceration in 1 patient. All but 1 patient underwent a Nissen fundoplication performed over a 50F to 60F dilator. The remaining patient (type II hernia without gastroesophageal reflux disease) underwent a reduction, closure, and anterior gastropexy. There was no operative mortality. Immediate postoperative morbidity included moderate dysphagia in 7 patients (11%), ileus in 2 patients (3%), and deep venous thrombosis and atrial arrhythmia in 1 each (1.5%). Excluding 1 patient hospitalized for 42 days due to severe psychosis, the mean postoperative stay was 4.0 +/- 2.5 days (median, 3 days). Three patients (5%) required dilation for dysphagia, and 1 (1.5%) has noted recurrent reflux during follow-up (mean, 14.4 months; range, 6 to 30 months). A single patient has undergone reoperation for persistent dysphagia (1.5%).

CONCLUSIONS

A laparoscopic Nissen procedure is safe, effective treatment for refractory gastroesophageal reflux disease when performed by thoracic surgeons experienced in minimally invasive surgical procedures.

Unilateral thoracoscopic surgical approach for diffuse emphysema

We evaluated the use of a lateral thoracoscopic approach for lung reduction surgery in patients with diffuse emphysema. Sixty-seven patients with a mean age of 61.9 years underwent operation. Operative side was determined by preoperative imaging. The procedures were laser ablation in 10 patients and stapler resection in 57 patients. Ten patients, including six of the 10 patients in the laser-only group had poor outcome (death or hospitalization longer than 30 days), leading us to abandon the laser technique. Of the remaining 57 patients undergoing primary stapled resection, duration of chest tube placement averaged 13 days (range 3 to 53 days) with a mean hospital stay of 17 days (range 6 to 99 days). Seven patients required ventilation for longer than 72 hours, six patients underwent conversion of the procedure to open thoracotomy, four patients acquired arrhythmias, and three patients were treated for empyema. There was one early death (1.7%), from cardiopulmonary failure. Forty patients returned for 3-month evaluation. Significant (p < 0.0001) improvements were seen in forced vital capacity (2.69 L after vs 2.26 L before) and forced expiration volume in 1 second (1.04 L after vs 0.82 L before), with 25 of 40 patients (63%) showing an improvement of more than 20%. Lung volume measures, in particular residual volume, fell significantly. Arterial blood gas analysis revealed that carbon dioxide tension fell significantly in patients with preoperative hypercapnia (carbon dioxide tension > 45 mm Hg, p = 0.018). Six-minute walk test results improved (894 feet after vs 784 feet before, p = 0.002), and symptomatic benefit was confirmed by significant improvement in the dyspnea index. The combination of both hypercapnia and reduced single-breath diffusing capacity for carbon monoxide was significantly more frequent (p = 0.0026) and was 86% specific (5 of 6 patients) in predicting serious postoperative risk. We conclude that the lateral thoracoscopic surgical approach to diffuse emphysema offers significant improvement in pulmonary mechanics and functional impairment. Patients with a combination of hypercapnia and reduced single-breath diffusing capacity for carbon monoxide should not be considered for this procedure because of significant perioperative risk.

Unsuspected lung cancer found in work-up for lung reduction operation

BACKGROUND

Lung reduction surgery is gaining acceptance in the treatment of patients suffering from severe diffuse emphysema. At the University of Pittsburgh 210 patients have been evaluated and 128 patients have undergone lung reduction operations.

METHODS

Ten patients, representing 7.8% of the operated group, have had asymptomatic cancerous or neoplastic lesions diagnosed on preoperative evaluation or pathologic analysis of resected tissue.

RESULTS

Six primary lung cancers (three squamous, three adenocarcinoma) and four other neoplastic lesions (squamous dysplasia, chemodectoma, and two carcinoid tumorlets) have been identified. All patients were heavy smokers, and all had markedly impaired pulmonary function. Patients whose lesions were identified on preoperative testing underwent thoracoscopic wedge excision of the tumor alone.

CONCLUSIONS

Our experience suggests that patients with impaired pulmonary function (chronic obstructive pulmonary disease) presenting for lung reduction operations are at a high risk of harboring an unsuspected neoplastic lesion. Complete preoperative evaluation of radiographic studies and preoperative bronchoscopic examination are mandatory.