Joseph LoCicero

Dissemination of malignant tumors after video-assisted thoracic surgery: A report of twenty-one cases ☆ ☆☆ ★ ★★

Video-assisted thoracic surgical techniques are widely used for biopsy and resection of thoracic tumors, but studies of long-term outcomes have not been reported. Dissemination of tumor by these techniques is a potential hazard. Therefore we surveyed the surgical members of the Video-Assisted Thoracic Surgery Study Group to determine whether tumor implants thought to be directly related to video-assisted techniques had occurred. Surgeons reported 21 cases. The sites of recurrence were the incision (n = 14), pulmonary staple line (n = 2), pleura (n = 2), both staple line and incision (n = 1), both pleura and incision (n = 1), and both pleura and staple line (n = 1). Review of these cases illustrates the pitfalls of present video-assisted techniques for malignant tumors of the thorax.

Spiral CT With Multiplanar and Three-Dimensional Reconstructions Accurately Predicts Tracheobronchial Pathology

BACKGROUNDnThis study was designed to evaluate the clinical accuracy of multiplanar reconstructions and three-dimensional shaded surface displays compared with conventional transaxial computed tomography, bronchoscopy, and surgical pathologic findings.nnnMETHODSnTransaxial computed tomographic images, two-dimensional nonstandard multiplanar reconstruction images, and three-dimensional images obtained from patients with tracheobronchial disease were prospectively evaluated for the relationship to adjacent structures, lesion characterization, and surgical anatomic correlation before invasive procedures.nnnRESULTSnCompared with conventional transaxial computed tomographic images, multiplanar reconstructions and three-dimensional shaded surface displays provided a correlative map of bronchoscopic and surgical anatomy in patients with benign and malignant tracheobronchial pathology. The longitudinal extent of abnormalities are better demonstrated on the multiplanar reconstruction and three-dimensional images, whereas the transverse extent of disease and relationships to adjacent structures were better shown on axial computed tomographic sections.nnnCONCLUSIONSnThree-dimensional and multiplanar two-dimensional images are additive to transaxial computed tomography for evaluation of diseases involving the central airways. They are beneficial for planning invasive procedures. More importantly, they provide consistent, highly accurate measurements for routine follow-up and for future clinical trials.

Thoracoscopic management of malignant pleural effusion

The diagnosis and management of pleural effusions have been well recognized over the years as indications for thoracoscopy. New technology has enhanced its appeal. Video-assisted thoracic surgery is a well-tolerated procedure that affords excellent visualization of the entire pleural surface. Directed biopsies of suspicious areas lead to a high diagnostic yield, particularly when compared with percutaneous biopsies. New algorithms reflect this fact. Video-assisted thoracic surgery now follows diagnostic thoracentesis as the next step in the evaluation of effusion suspicious for malignancy. Video-assisted thoracic surgery can also aid the lysis of adhesions, which might limit the effectiveness of surgical procedures to produce pleurodesis, and is an ideal tool for therapeutic management. It may be performed with general anesthesia or local anesthesia and sedation. All of the pleural fluid can be removed and this facilitates the procedure. With minimal instrumentation, pleurodesis may be performed by pleurectomy, mechanical abrasion, or talc sclerosis. Visually directed placement of chest tubes ensures adequate reexpansion of the lung.

Magnesium cardioplegia reduces cytosolic and nuclear calcium and DNA fragmentation in the senescent myocardium.

Previous reports have indicated that the senescent myocardium is less tolerant to surgically induced ischemia and that diminished functional recovery is associated with alterations in cytosolic calcium ([Ca2+]i) accumulation. Recently, increased [Ca2+]i has been suggested to alter nuclear calcium ([Ca2+]n) accumulation. To investigate the relation between [Ca2+]i and [Ca2+]n, we subjected mature and aged rabbit hearts to normothermic global ischemia, either without treatment or after treatment with potassium cardioplegia, magnesium cardioplegia, or a combination of potassium and magnesium cardioplegia. The relation between altered [Ca2+]n and DNA fragmentation was also investigated. Our results indicate that [Ca2+]i was increased during 30 minutes of normothermic global ischemia without treatment in both the mature and aged hearts (p < 0.05). Accumulation of [Ca2+]i during global ischemia was reduced with the use of potassium, magnesium, and a combination of potassium and magnesium cardioplegia (p < 0.05 versus untreated ischemia) in both the mature and aged hearts. Levels of [Ca2+]n were unaffected by global ischemia or cardioplegia in the mature myocardium; however, in the aged myocardium, [Ca2+]n was increased during global ischemia and with potassium cardioplegia and was associated with increased nuclear DNA fragmentation (p < 0.05). The use of magnesium and a combination of potassium and magnesium cardioplegia attenuated [Ca2+]n accumulation and nuclear DNA fragmentation (p < 0.05). Control of [Ca2+]i and [Ca2+]n was associated with enhanced functional recovery during reperfusion. These results indicate that during normothermic ischemia, there is increased [Ca2+]i and [Ca2+]n in the aged myocardium, and increased [Ca2+]n is associated with increased nuclear DNA fragmentation.(ABSTRACT TRUNCATED AT 250 WORDS)

Video-Assisted Thoracic Surgery Study Group☆

Both patients and the medical profession are quick to embrace new technology, particularly when it may replace an existing surgical procedure. Unfortunately, the rapidity of acceptance is rarely associated with careful evaluation. Laparoscopy is a recent example of such widely embraced technology. Studies of laparoscopy that yielded good comparative data to more traditional methods were slow to accrue. This led to the exposure of its shortcomings through governmental reports and the lay press. To prevent this from happening in thoracoscopy, two types of studies are required so that valid conclusions about the new technology can be drawn. The first is an accounting of the new technology as procedures evolve around it. The data collected in such a study should contain basic information, including the indications for the procedure, how it was performed, procedure length, associated complications, and patient outcome. Such information provides a broad profile of the technology, emphasizing from the outset its potential strengths and weaknesses. The second type of study involves a more detailed concurrent comparison of the specific procedures utilizing this technology to the established traditional methods. Such randomized studies help to firmly establish through scientific process the place of the new technology. The Video-Assisted Thoracic Surgery Study Group was organized in early 1992 to address these concerns. From an initial four surgeons the group has grown to include more than 41 institutions. Currently the group is collecting data in a registry and has established three clinical trials to evaluate video-assisted thoracic surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of initial flush potassium concentration on the adequacy of lung preservation

The effects of initial lung flushing with intracellular and extracellular fluid type solutions were studied in lungs stored with the University of Wisconsin solution. Excised Sprague-Dawley rat lungs (n = 39) were flushed first with one of the following solutions: (1) the University of Wisconsin solution (K+ = 140 mmol/L), (2) modified (low potassium) University of Wisconsin solution (K+ = 20 mmol/L), (3) phosphate buffered saline solution (K+ = 3.9 mmol/L), (4) modified low-potassium phosphate-buffered saline solution (K+ = 20 mmol/L), (5) modified high-potassium phosphate-buffered saline solution (K+ = 40 mmol/L), and (6) Euro-Collins solution (K+ = 115 mmol/L) followed by secondary flush with storage solution and cold (4 degrees C) storage in University of Wisconsin solution for 24 hours. The lungs were then reperfused in the isolated, pulsatile, blood-perfused working lung system for 2 hours or until lung failure. Blood gas analysis and shunt fraction, aerodynamic parameters (airway resistance, lung compliance, elastic work, and flow resistive work), and total pulmonary vascular resistance were measured throughout the perfusion period. The mean oxygen tensions (in millimeters of mercury) at 30 minutes after the onset of reperfusion for University of Wisconsin solution, modified University of Wisconsin solution, phosphate-buffered saline solution, modified phosphate-buffered saline solutions (20 and 40 mmol/L), and Euro-Collins solution were 56.1 +/- 4.2, 72.7 +/- 9.1, 87.7 +/- 6.9 (p < 0.01 versus University of Wisconsin solution; p < 0.01 versus Euro-Collins solution), 86.0 +/- 9.6 (p < 0.01 versus University of Wisconsin solution; p < 0.01 versus Euro-Collins solution), 87.9 +/- 7.7 (p < 0.01 versus University of Wisconsin solution; p < 0.01 versus Euro-Collins solution), and 53.5 +/- 6.0, respectively. All aerodynamic parameters in the lungs flushed with extracellular fluid type solutions were superior to those flushed with intracellular fluid type solutions. We conclude that the efficacy of initial flushing was essential for successful lung preservation and that extracellular fluid type solutions were superior to intracellular fluid type solutions, at least for flushing the lung before storage with University of Wisconsin solution. Potassium concentration in flushing solution should be 20 mmol/L or less to obtain appropriate flushing and subsequent adequate distribution of the storage solution.

Calcium channel blocker enhances lung preservation

BACKGROUNDnThe standard program for lung transplantation employs PGE1 pretreatment for donor lungs, but its efficacy remains controversial. Calcium channel blocker has been reported more effective for reducing potassium-induced vasoconstriction. We investigate the efficacy of calcium channel blocker in the initial lung flush using rat lung transplant model.nnnMETHODSnThe excised rat lungs (n = 30) were flushed with either University of Wisconsin solution (UWS) with a prior injection of 50 microg/kg PGE1 into the pulmonary artery (UWS + PGE1; n = 7), UWS only (UWS; n = 7), or UWS containing 10(-6) M nifedipine (UWS + Nif; n = 8). After storage (4 degrees C) for 24 hours, all lungs were reperfused for 2 hours using an isolated, pulsatile blood perfused lung model. Control lungs (n = 8) were reperfused immediately after harvest. Blood gas analysis and shunt fraction, lung airway resistance, dynamic lung compliance, and pulmonary vascular resistance were assessed.nnnRESULTSnThe pO2 at 30 minutes after reperfusion in the control, UWS, UWS + PGE1, and UWS + Nif group were 88.0 +/- 3.2, 49.6 +/- 2.2, 52.0 +/- 2.4, 85.1 +/- 2.1 (mmHg), respectively. Until 30 minutes after reperfusion, the pO2 in UWS and UWS + PGE1 group were significantly lower than those in UWS + Nif group (p < .001). Shunt fraction, lung airway resistance, and dynamic lung compliance also demonstrated the superiority of UWS + Nif group.nnnCONCLUSIONSnThe early graft function after storage was significantly enhanced in lungs flushed with UWS containing nifedipine. Calcium channel blocker is more effective than PGE1 in reducing the potassium-induced vasoconstriction. Optimal composition of the flush may require both calcium channel blocker for pulmonary vasodilation and PGE1 for pulmonary protection by non-vasodilatory mechanisms.

Heat shock protein suppresses the senescent lung cytokine response to acute endotoxemia

BACKGROUNDnPrevious reports demonstrate that heat shock protein (HSP) can alter the pulmonary inflammatory cascade. We wished to determine if this mechanism is active in the senescent mouse.nnnMETHODSnA dose-response and time-response curve for sodium arsenite (SA) induction of HSP was constructed. Eight 25-month-old B6C3F1 mice were given either 1, 2, 4, or 6 mg/kg SA. At 4 hours, the lungs were harvested and assayed for HSP by Western blot. Next, 8 mice were given 4 mg/kg SA and the lungs harvested at either 1, 2, 4, or 6 hours after injection and assayed for HSP. Next, 12 mice were prepared: Half received 4 mg/kg SA and 4 hours later, all received 0.5 mg/kg lipopolysaccharide (LPS). After 4 hours, lungs were harvested and Interleukin-1beta mRNA was assayed by Northern blot and semi-quantified by densitometry.nnnRESULTSnThe optimum SA dose was determined to be 4 mg/kg. The maximum HSP production was at 4 hours. Mice receiving LPS only showed a marked increase (3-fold) in IL-1 message compared with the mice pretreated with SA.nnnCONCLUSIONSnThese data suggest that in the senescent as in the mature mouse lung, HSP downregulates the inflammatory cascade in response to LPS.

Does PGE1 attenuate potassium-induced vasoconstriction in initial pulmonary artery flush on lung preservation?

The standard clinical protocol for lung transplantation employs cold single pulmonary artery flush with Euro-Collins solution or the University of Wisconsin solution. Prostaglandin E1 (PGE1) is usually given by direct injection into the pulmonary artery to reduce pulmonary vasoconstriction caused by these intracellular, high-potassium solutions, however, the efficacy of PGE1 on lung preservation remains controversial. In this study we demonstrated that vasodilator effects of PGE1 were markedly reduced under a high-potassium condition, and that potassium-induced pulmonary vasoconstriction were inhibited by calcium channel blocker nifedipine. There are three therapeutic options in the cold single pulmonary artery flush for optimal lung transplantation, including the use of a higher dose of PGE1, use of the calcium channel blocker instead of PGE1, or the use of the extracellular, low-potassium solution such as low-potassium dextran solution for initial pulmonary artery flush before the lung harvest.

Lung preservation threshold in a compromised septic lung injury model.

BACKGROUNDnDiscrepancy between clinical and research works in lung transplantation could be due to differences between compromised clinical donor lungs and intact research lungs. The purpose of this laboratory study was to produce compromised lungs to compare with normal ones.nnnMETHODSnSprague-Dawley rats were continuously infused with lipopolysaccharide (5 mg/kg) for 24 hours before organ harvest. Lungs were stored in University of Wisconsin solution at 4 degrees C for the following period: group 1: intact lungs, no storage (n = 12); group 2: septic lungs, no storage (n = 6); group 3: septic lungs for 6 hours (n = 5); and group 4: septic lungs for 12 hours (n = 5). All lungs were reperfused for 2 hours with venous blood using an isolated, pulsatile perfused lung system.nnnRESULTSnExperimental variables were comparable between groups 1, 2, and 3. All septic lungs stored for 12 hours (group 4) failed within 1 hour of perfusion.nnnCONCLUSIONSnThese results indicate that compromised lungs with septic injury functioned at near control levels after 6 hours of preservation. Six hours may be a safe limit for human donor lungs, all of which are compromised in some way by the time of harvest.