The effect of elevated dietary cholesterol on pulmonary surfactant function in adolescent mice.

It has been established that phospholipids and cholesterol interact in films of pulmonary surfactant (PS). Generally it is thought that phospholipids increase film stability whereas cholesterol increases film fluidity. To study this further, we modified dietary cholesterol in mice which received either standard rodent lacking cholesterol (sd), or high cholesterol (2%) diet (hc) for 1 month. Phospholipid stability was investigated by a capillary surfactometer (CS), which measures airflow resistance and patency. PS was collected by bronchiolar lavage and centrifuged to obtain the surface-active film (SAF). Results showed that the hc-SAF had significantly more cholesterol than sd-SAF. CS analyses at 37 degrees C showed no significance differences in airflow resistance between hc-SAF and sd-SAF. However, at 37 degrees C, sd-SAF showed greater ability to maintain patency compared to hc-SAF, whereas at 42 degrees C hc-SAF showed patency ability similar to sd-SAF. The results suggested that increased cholesterol in hc-SAF induced less stability in the SAF possibly due to cholesterol's fluidizing effect on phospholipids at physiological temperatures.

The biophysics of asthmatic airway smooth muscle.

It is clear that significant advances have been made in the understanding of the physiology, biochemistry and molecular biology of airway smooth muscle (ASM) contraction and how the knowledge obtained from these approaches may be used to elucidate the pathogenesis of asthma. Not to belittle other theories of smooth muscle contraction extant in the field, perhaps the most outstanding development has been the formulation of plasticity theory. This may radically alter our understanding of smooth muscle contraction. Its message is that while shortening velocity and capacity are linear functions of length, active force is length independent. These changes are explained by the ability of thick filament protein to depolymerize at short lengths and to increase numbers of contractile units in series at lengths greater than optimal length or L(ref). Other advances are represented by the report that the major part of ASM shortening is complete within the initial first 20% of contraction time, that the nature and history of loading determine the extent of shortening and that these findings can be explained by the finding that the crossbridges are cycling four times faster than in the remaining time. Another unexpected finding is that late in the course of isotonic relaxation the muscle undergoes spontaneous activation which delays relaxation and smoothes it out; speculatively this could minimize turbulence of airflow. On the applied front evidence now shows the shortening ability of bronchial smooth muscle of human subjects of asthma is significantly increased. Measurements also indicate that increased smooth muscle myosin light chain kinase content, via increased actomyosin ATPase activity could be responsible for the changes in contractility.

Lung volume reduction surgery for the treatment of severe emphysema: a study in a single Canadian institution.

OBJECTIVE: To evaluate lung volume reduction surgery (LVRS) and its effectiveness in improving pulmonary function, exercise capacity and quality of life in a population of emphysema patients referred to and screened in a single centre. DESIGN: A prospective case series. SETTING: A Canadian tertiary care hospital. PATIENTS: Patients with severe emphysema, significant dyspnea and impaired exercise capacity interfering with quality of life. INTERVENTIONS: Bilateral LVRS was performed through a median sternotomy. MAIN OUTCOME MEASURES: Pulmonary function tests (preoperative forced expiratory volume in the first second [FEV1], residual volume [RV]), 6-minute walk (6 MW) distance, quality of life (Medical Outcomes Study 36-item short-form health survey) and degree of dyspnea (Medical Research Council of Great Britain dyspnea scale and the baseline and transitional dyspnea indices) were assessed before LVRS and at 6 and 12 months after. RESULTS: Fifty-seven patients were assessed for LVRS, of whom 10 were selected for surgery. Homogeneous distribution of disease was the most common reason for exclusion. Of the 10 patients operated upon, 1 died of acute cor pulmonale on the fourth postoperative day and 1 died of recurrent exacerbations of chronic obstructive pulmonary disease and chronic respiratory failure at 315 days postoperatively. In the surviving patients, the mean preoperative FEV1 increased from 0.70 L before surgery to 0.90 L at 1 year, with a mean relative increase of 33.4%. The mean RV decreased from 5.57 L to 4.10 L, with a mean relative decrease of 27.6%. The 6 MW distance increased from 302.7 m to 356.9 m at 1 year, with a mean relative increase of 21.6%. Quality of life and degree of dyspnea were improved significantly at 1 year after LVRS. Of the 5 patients on oxygen at home before surgery, 4 were able to reduce their requirements but not to discontinue oxygen. CONCLUSIONS: LVRS is an effective palliative treatment for dyspnea and poor exercise tolerance in highly selected patients. Although the duration of palliation is unknown, our results show that improvements in pulmonary function, exercise, quality of life and degree of dyspnea are preserved over the first year. Only a minority of the patients screened were eligible for surgery. The 2 deaths in our series emphasize the need for even further delineation of selection criteria.

Antiestrogens sensitize human ovarian and lung carcinomas for lysis by autologous killer cells.

BACKGROUND: The antiestrogens tamoxifen (TX) and toremifene (TO) were shown previously to enhance the lysis of target cells by natural killer cells (NK), lymphokine activated killer (LAK) cells, and by cytotoxic T lymphocytes (CTL). MATERIALS AND METHODS: CTL were cultured from lung cancer tissue and from ascites fluid of ovarian carcinoma patients with the aid of human recombinant interleukin-2 (hrIL-2). The target, effector or both cell populations were pretreated by TX, TO and/or with human recombinant interferon-alpha (IFN-alpha). RESULTS: Significant enhancement of cytotoxicity occurred when the tumor targets or both the target and effector cells were treated with TX, TO or when these drugs were used in combination with IFN-alpha. The lytic activity of CTL cultured from draining lymph nodes of lung cancer patients, was also observed after similar treatment. The lytic effect of autologous LAK cells derived from peripheral blood was increased to a lesser extent, which could be amplified by additional treatment with IFN-alpha. CONCLUSIONS: The antiestrogens TX and TO and IFN-alpha enhance the lysis of autologous tumor cells by CTL and LAK effectors.

Histamine H3 receptor blockade improves cardiac function in canine anaphylaxis.

In anaphylactic shock (AS), the relative effects of the autacoids including histamine, prostaglandins, and leukotrienes on causing cardiovascular collapse and the extent to which receptor blocking agents and pathway inhibitors may prevent this collapse are not clear. In a ragweed model of anaphylaxis, we examined whether pretreatment with H1, H2, H3 receptor blockers, and cyclooxygenase and leukotriene pathway inhibitors was useful in preventing the depression in left ventricular (LV) contractility known to occur in this model. The dose of allergen was varied to produce similar degrees of shock between treatments. The animals were studied under pentobarbital anesthesia in which the treatment studies were approximately 3 wk apart. LV volumes were measured by sonomicrometric techniques. During challenge, mean arterial blood pressure (Pa), cardiac output (Q), and LV end-diastolic pressure (LVEDP) decreased approximately 50% compared with preshock values in all treatments. Histamine H3 receptor blockade was associated with higher heart rates (HR) and higher stroke work (SW) (p < 0.05) as compared with the other treatment studies. We conclude that histamine H3 activation by inhibiting adrenergic neural norepinephrine release contributes to cardiovascular collapse in AS.

Role of autacoids in cardiovascular colapse in anaphylactic shock in anaesthetized dogs.

OBJECTIVE: In anaphylactic shock (AS), the relative effects of the autacoids including histamine, prostaglandins (prost), and leukotrienes (leuk) on causing cardiovascular collapse and the extent to which receptor blocking agents and pathway inhibitors may prevent this collapse are not clear. METHODS: In randomized design, we investigated whether blockade of histamine H1, H2, and H3 receptors or inhibition of the cyclooxygenase (cyclo) and lipoxygenase pathways (lipox) prevented AS in ragweed sensitized dogs. Seven dogs were studied under pentobarbital anesthesia in which the treatment studies were approximately 2 weeks apart. RESULTS: During H1 receptor blockade, the decreases in blood pressure and cardiac output otherwise observed in AS were attenuated (P < 0.05) and the release of prost, thromboxanes, and leuk were reduced as compared with nontreatment studies. Cyclo inhibition also attenuated cardiovascular collapse and mediator release in AS, but the other treatments showed no effects. CONCLUSION: H1 receptor blockade and cyclo may attenuate cardiovascular shock in AS. These agents inhibit autacoid release from mast cells in addition to any specific receptor blocking and pathway inhibition effects.

Effects of anaphylaxis mediators on partitioned pulmonary vascular resistance during ragweed shock in dogs.

We examined the effect of anaphylactic shock on the longitudinal distribution of pulmonary vascular resistance (PVR) in ragweed-sensitized dogs in which PVR was partitioned into an upstream arterial component (Rus) and a downstream venous and capillary component (Rds). We also assessed whether Rus and Rds would be reduced by pretreatment with histamine H1- and H2-receptor blocking agents and with cyclooxygenase and lipoxygenase pathway inhibitors. Anesthetized animals were examined on separate occasions 3 wk apart in which one of the treatments was randomly given. The pulmonary arterial occlusion technique was used to determine segmental pressure drops. During ragweed challenge, PVR increased approximately 4 times compared with the preshock value (3.04 vs. 12. 07 mmHg . l-1 . min; P < 0.05). Although both Rus and Rds increased postshock, the greatest relative increase occurred in Rds. None of the treatments reduced partitioned resistances compared with no treatment. Our results show that, under conditions of anaphylactic shock, increases in Rus and Rds could not be ascribed to release of histamine or products of the cyclooxygenase and lipoxygenase pathways.

Effect of bolus epinephrine on systemic hemodynamics in canine anaphylactic shock.

OBJECTIVE: Epinephrine (Epi) is considered to be the drug of choice for anaphylactic shock (AS). However, the benefit of this drug on improving systemic hemodynamics in AS has never been shown. We used a canine ragweed model of AS to determine if an intravenous bolus of Epi hastened the recovery of hemodynamics and modified mediator release (Med) compared with no treatment (NT). METHODS: In one protocol (n = 8), the effects on hemodynamics of two intravenous doses of Epi (0.01 and 0.025 mg/kg) were examined for 3 h postshock in respective studies approximately three weeks apart under pentobarbital anesthesia in the same animal. In five other dogs, left ventricular (LV) mechanics were additionally determined by sonomicrometric techniques to determine changes in contractility as defined by the preload recruitable stroke-work (SW) relationship. RESULTS: Compared with NT values, Epi treatments produced only transient increases in mean arterial pressure (MAP) and cardiac output (CO) post-challenge. By 20 min postshock, CO in the Epi studies were generally lower (p < 0.05) and BP was not different from NT values. With Epi treatment, SW was reduced for a given LV end-diastolic volume compared with the control study. Epi treatments also caused relatively higher plasma thromboxane B2 concentrations postshock. CONCLUSION: Our findings indicate that, when given immediately postshock, bolus-Epi did not hasten recovery and caused impairment in LV mechanics in canine AS.

Epinephrine decreases postoperative requirements for continuous thoracic epidural fentanyl infusions.

Epidural thoracic fentanyl infusions provide effective preoperative analgesia after thoracotomy; however, side effects can limit the effectiveness of this technique. This study evaluates epinephrine as an adjunct to continuous thoracic epidural fentanyl infusions after thoracotomy. Thirty-eight patients were studied in a prospective, randomized, double-blind trial comparing fentanyl alone to fentanyl with epinephrine 1:300,000. Epidural infusion rates were titrated to equivalent pain relief using a visual analog scale. With the addition of epinephrine, there was a significant reduction in fentanyl requirements (0.82 +/- 0.07 vs 1.19 +/- 0.11 micrograms.kg-1.h-1, P = 0.005, repeated-measures analysis of variance) and in plasma fentanyl concentrations (steady state: 0.91 +/- 0.13 vs 1.65 +/- 0.23 ng/mL, P = 0.007, repeated-measures analysis of variance). There were no differences in pain scores, side effects, spirometry, patient satisfaction scores, or hemodynamic variables. This study demonstrates that adding epinephrine 1:300,000 to continuous thoracic epidural infusions decreases fentanyl requirements titrated for effective analgesia. The reduction in fentanyl requirements was associated with reduced fentanyl plasma concentrations.

Placement of left double-lumen endobronchial tubes with or without a stylet.

PURPOSE: This study was designed to determine if leaving a stylet in the left Bronch-Cath endobronchial tube (DLT) for the entire intubating procedure improves the accuracy of placement on the initial attempt, without introducing complications. METHODS: Sixty ASA 1-3 patients were randomized to one of two groups. In Group 1 (n = 30), the stylet was retained for the entire intubation procedure and in Group 2 (n = 30), the stylet was removed once the bronchial cuff had passed the vocal cords. In both groups, the DLT was turned 110 degrees counterclockwise and advanced until resistance was encountered. Placement was assessed by auscultation and fibreoptic bronchoscopy (FOB). After surgery, the DLT was replaced by a single-lumen endotracheal tube. The thoracic surgeon (blinded to the method of intubation, and using a FOB) assessed the appearance of the tracheobronchial mucosa. RESULTS: The two groups were similar with respect to sex, height, weight, DLT size, surgeon and expertise of the laryngoscopist. When the stylet was retained, the DLT was correctly placed 60% of the time compared with 17%, if the stylet was removed, (P = 0.001). Seven out of 30 DLTs in Group 2 were initially placed into the right mainstem bronchus, (P = 0.005). The average time to confirmation of correct tube placement by FOB was increased in Group 2, (P = 0.01). Although the observed incidence of left bronchial, mucosal petechiae and erythema was greater in Group 2, this was not statistically significant, (P = 0.063). CONCLUSION: Retaining the stylet for the entire intubation procedure allows for a more rapid, accurate placement of the DLT without increasing the incidence of tracheobronchial mucosa injury.

TGF-beta 1, but not TGF-beta 2 or TGF-beta 3, is differentially present in epithelial cells of advanced pulmonary fibrosis: an immunohistochemical study.

Although it is recognized that three isoforms of transforming growth factor-beta (TGF-beta) exist in mammals, their expression, distribution, and function in injury and repair are not well characterized. Using immunohistochemistry and antibodies to synthetic peptides of TGF-beta 1, TGF-beta 2, and TGF-beta 3, we determined the distribution of TGF-beta isoforms in lung sections with acute and chronic lesions of idiopathic pulmonary fibrosis (IPF), chronic asbestosis and hypersensitivity pneumonitis, as well as non-specific pneumonitis. In lung sections with advanced pulmonary fibrosis and honeycombing, irrespective of the diagnosis, TGF-beta 1 was prominently expressed in epithelial cells and macrophages and was found to be associated with the extracellular matrix. In lungs with early lesions of IPF and only inflammatory changes, TGF-beta 1 was present in alveolar macrophages but TGF-beta 1 was not present in epithelial cells. Small amounts of matrix-associated TGF-beta 1 were present subepithelially in areas of lung sections from patients with IPF with minimal inflammation and no fibrosis. In normal lungs with no evidence of inflammation or fibrosis TGF-beta 1 was not seen in alveolar macrophages, epithelial cells, or extracellularly. TGF-beta 2 and TGF-beta 3 were expressed in alveolar macrophages, epithelial cells, and smooth muscle cells of vessels and bronchi of normal lungs and lungs with both inflammatory and fibrotic changes. Our findings suggest that while TGF-beta 2 and TGF-beta 3 are ubiquitously expressed in the lung, TGF-beta 1 is expressed in epithelial cells of fibrotic lungs where the presence of TGF-beta 1 is not disease-specific but an indication of the chronicity of the injury.

Lung preservation and lung injury.

Lung preservation and its attendant ischemia-reperfusion injury is a complex phenomenon that begins with lung injury that may be present in the donor before any preservation intervention. Acute preservation interventions in common use include single-flush perfusion and donor core-cooling on cardiopulmonary bypass. From this moment forward the ischemia injury begins, and increases during the phase of organ storage. The lung continues to metabolize glucose even at these low temperatures, and future improvements may well lie in recognizing this requirement. With reperfusion, another phase of lung injury begins as the ischemic lung is overloaded with oxygen and oxygen free radicals are generated. Research efforts have focused on minimizing the effect of free-radicals at various steps along their formation and diminishing their interaction with cell membranes.

Cardiopulmonary bypass resuscitation for accidental hypothermia.

Many victims of accidental hypothermia have been successfully resuscitated with cardiopulmonary bypass, but questions remain regarding treatment indications and efficacy. To assess the role of cardiopulmonary bypass in resuscitation from hypothermia, a collective literature review was performed. Data on 68 hypothermic patients resuscitated with cardiopulmonary bypass were analyzed. Impairment from alcohol, drug abuse, or mental illness was the most common predisposing factor for accidental hypothermia. Mean initial core temperature was 21 degrees C. Sixty-one patients (90%) were in cardiac arrest. Femoral-femoral bypass was used in 72% of patients. Overall survival was 60%. Eighty percent of survivors returned to their previous level of function. Sixty-seven percent of nonsurvivors died because of inability to establish a cardiac rhythm or wean from bypass. Patient age, type of cardiopulmonary bypass (femoral-femoral or atrial-aortic), and initial core temperature were not significant prognostic indicators. There were no survivors among the 6 patients with a core temperature less than 15 degrees C. Patients in cardiac arrest had a higher mortality than patients who were not (p = 0.02). Climbing and avalanche victims had a higher mortality than other hypothermic patients (p = 0.003). The possibility of publication bias must be considered before firm conclusions can be drawn from this collective literature review. Controlled studies comparing the efficacy of cardiopulmonary bypass and alternative warming techniques have not been done. Nevertheless, cardiopulmonary bypass has several advantages over other warming methods for profoundly hypothermic patients. Tissue perfusion and oxygenation are maintained while rapid warming occurs. Cardiopulmonary bypass resuscitation is recommended for hypothermic patients in arrest and for patients with core temperatures lower than 25 degrees C, irrespective of rhythm. Patients in stable condition with temperatures between 25 degrees and 28 degrees C can be treated with cardiopulmonary bypass or conventional warming methods.

Left ventricular systolic performance is depressed in chronic pulmonary emphysema in dogs.

The effect of chronic right ventricular (RV) pressure overload on left ventricular (LV) systolic function in chronic obstructive lung disease is unclear. To examine LV systolic performance in pulmonary emphysema, a chronic canine model was developed in which pulmonary artery pressure could be elevated to a level found in human disease. Severe emphysema was produced by the repeated instillations of the enzyme papain into the lung. Sonomicrometry was used to assess LV dimensions along the septal-lateral, apex-base, and anterior-posterior orthogonal axes of the LV. With the animal conscious, measurements of LV systolic function were obtained over a wide range of LV circumferential end-ejection stresses at baseline and after 1 yr of emphysema (post-1-yr study). In the emphysema group (n = 5), the results showed that at the post-1-yr study, measurements of LV ejection fraction, mean velocity of circumferential shortening, and rate of anterior-posterior dimensional shortening were reduced compared with those obtained at the baseline study. In the emphysema group, end-systolic volume was increased for a given end-systolic pressure or stress at the post-1-yr study compared with baseline values, while fractional shortening measured along the three axes was decreased. There were no similar changes in systolic parameters in control groups. We conclude that chronic RV pressure overload may cause an impairment in LV systolic performance in chronic emphysema.

Diagnostic algorithm for acute superior vena caval obstruction (SVCO).

Acute SVCO presents a serious diagnostic and therapeutic dilemma to the thoracic surgeon. It is highly desirable to obtain a definitive tissue diagnosis but this requirement must be balanced against the risks inherent in invasive diagnostic procedures in these oft-times critically ill patients. In the past 5 years we have developed an algorithm that has been used successfully in 18 patients presenting with acute SVCO. The decision tree consists of scalene node biopsy, bronchoscopy and mediastinoscopy with categorization into low and high risk groups in the latter. The gender distribution of the 18 patients was 12 male and 6 female with the ages being 58.3 +/- 16.3 and 64.2 +/- 11.2 years respectively. The duration of symptoms range from 1.5 to 12 weeks and averaged 4.5 +/- 3.2 weeks. Two patients had palpable scalene nodes which were positive at biopsy. Bronchoscopy was positive in 5 out of 11 examinations. In 5 instances it was not done. Twelve patients underwent various forms of mediastinal biopsy and one underwent sternotomy. Seven patients requiring mediastinoscopy were judged to be high risk as defined by severe airway and vascular obstruction. Perioperative difficulties occurred in two patients due to cardiorespiratory factors associated with the obstruction. Both patients were undergoing cervical mediastinoscopy under general anesthesia and no difficulties were encountered in high risk patients when local anesthesia was used to perform anterior mediastinotomy. Five patients that were considered low risk all underwent uncomplicated procedures under general anesthesia. Thirteen patients proved to have bronchogenic carcinoma and a specific tissue diagnosis was obtained in 12. The undetermined diagnosis was in a patient who had prior radiotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary endothelial cell function after modified Eurocollins solution infusion.

Eurocollins solution is commonly used in preparation for lung transplantation and is known to increase the pressure cost of perfusion by causing both vascular obstruction and increased tone. In this study we assessed whether Eurocollins solution had a direct effect on the pulmonary endothelial cell by causing increased permeability or by depressing its metabolic integrity. The effect of 4 degrees C Eurocollins solution on transvascular fluid flux properties and on angiotensin-converting enzyme function were assessed. Eurocollins solution had no effect on the microvascular filtration coefficient or on the critical capillary pressure, both very sensitive indicators of the permeability characteristics of the endothelium. The inert angiotensin-converting enzyme substrate [3H]BPAP had a peak metabolism of 83% and 81%, respectively, and an average metabolism of 82% both before and after Eurocollins solution infusion. The first order enzyme rate constant, Vmax/Km, was, however, reduced by 22% with Eurocollins solution perfusion. Eurocollins solution does not therefore cause increased endothelial permeability and hence a permeability type of pulmonary edema. The reduced first order rate constant of the enzyme, in the presence of normal peak and average metabolism, may be partially accounted for by a reduction in intravascular surface area available for enzyme substrate interaction.

Thoracic versus lumbar epidural fentanyl for postthoracotomy pain.

Thirty patients were prospectively randomized to receive either thoracic or lumbar epidural fentanyl infusion for postthoracotomy pain. Epidural catheters were inserted, and placement was confirmed with local anesthetic testing before operation. General anesthesia consisted of nitrous oxide, oxygen, isoflurane, intravenous fentanyl citrate (5 micrograms/kg), and vecuronium bromide. Pain was measured by a visual analogue scale (0 = no pain to 10 = worst pain ever). Postoperatively, patients received epidural fentanyl in titrated doses every 15 minutes until the visual analogue scale score was less than 4 or until a maximum fentanyl dose of 150 micrograms by bolus and an infusion rate of 150 micrograms/h was reached. The visual analogue scale score of patients who received thoracic infusion decreased from 8.8 +/- 0.5 to 5.5 +/- 0.7 (p < or = 0.05) by 15 minutes and to 3.5 +/- 0.4 (p < or = 0.05) by 45 minutes. The corresponding values in the lumbar group were 8.8 +/- 0.6 to 7.8 +/- 0.7 at 15 minutes and 5.3 +/- 0.9 at 45 minutes (p < or = 0.05). The infusion rate needed to maintain a visual analogue scale score of less than 4 was lower in the thoracic group (1.55 +/- 0.13 micrograms.kg-1 x h-1) than in the lumbar group (2.06 +/- 0.19 microgram.kg-1 x h-1) during the first 4 hours after operation (p < or = 0.05). The epidural fentanyl infusion rates could be reduced at 4, 24, and 48 hours after operation without compromising pain relief. Four patients in the lumbar group required naloxone hydrochloride intravenously.(ABSTRACT TRUNCATED AT 250 WORDS)

Altered left ventricular chamber stiffness and isovolumic relaxation in dogs with chronic pulmonary hypertension caused by emphysema.

BACKGROUND: In chronic obstructive lung disease, a right to left ventricular septal shift that occurs as a consequence of right ventricular pressure overload is the usual mechanism given to explain a decrease in left ventricular (LV) diastolic performance. The purpose of the present study was to examine the extent to which this mechanism could account for a decrease in LV diastolic function in a canine model in which pulmonary artery pressure was elevated to a level found in human disease. METHODS AND RESULTS: Severe emphysema was produced in dogs by repeated instillations of the enzyme papain into the lung. To assess LV diastolic function, we used sonomicrometry, in which three pairs of subendocardial crystal transducers were implanted along the three orthogonal axes of the LV. LV end-diastolic dimensions and pressure-strain relations along the three axes, as well as the time constant of LV isovolumic relaxation (T), were measured before (baseline) and after 1 year of emphysema (post-1-year study). The results showed that after 1 year of pulmonary hypertension, LV pressure-strain relations were decreased along the septal-lateral and anterior-posterior axes, but a right to left ventricular septal shift was not detected. The relation of average midwall circumferential stress to midwall circumferential strain was used to describe the intrinsic compliance of the LV. The results showed that myocardial stiffness increased in emphysema but that chamber volume was not reduced. At the post-1-year study, T was abnormally increased in the emphysema group in response to augmented preload and afterload compared with preemphysema measurements. CONCLUSIONS: We conclude that mechanisms other than ventricular interdependence may be operative in leading to altered LV diastolic filling in chronic emphysema.

Vascular and interstitial effect of University of Wisconsin solution on canine lung.

Belzer's University of Wisconsin cold storage solution (UWCSS) has proved useful in extending the shelf life of organs in extrathoracic transplantation and more recently has also been shown to be useful in heart transplantation. I investigated the effect of 4 degrees C UWCSS on the vascular and interstitial properties of the lung to see whether it affected the pulmonary microcirculation or caused pulmonary edema. Infusion of UWCSS was associated with a slight decrease in oxygen tension, but the final oxygen tension was no different from that previously demonstrated with Euro-Collins solution. Vascular conductance was not affected by UWCSS, but average vascular closure increased slightly, indicating that increased vascular tone occurs. This effect is similar to but less than that previously observed with Euro-Collins solution. Based on comparisons of wet to dry weight ratios, estimates of interstitial compliance, transvascular fluid flux, and microvascular filtration coefficient, it does not appear that UWCSS causes pulmonary edema. Further investigation into the usefulness of UWCSS in lung transplantation is therefore warranted.

Plasma cell granuloma of the lung.

Plasma cell granuloma is an uncommon, nonneoplastic pulmonary lesion. An 11-year retrospective review of resected pulmonary tumors yielded six patients with plasma cell granulomas. Fine needle aspiration biopsy results were falsely positive for carcinoma in one patient. Adherence or invasion of the mediastinum was present in three patients. Granuloma in one patient, who underwent two operative procedures, was deemed unresectable at the initial thoracotomy. For both diagnostic and therapeutic reasons, early surgical excision is recommended for plasma cell granulomas of the lung.