Scott B. Johnson

Management of major tracheobronchial injuries : a 28-year experience

Abstract Background . Tracheobronchial injuries are rare but potentially life threatening. Their successful diagnosis and treatment often require a high level of suspicion and surgical repairs unique to the given injury. Methods . We reviewed our experience with 32 patients with tracheobronchial injuries treated over the past 28 years. Results . Forty-one percent (13/32) of the injuries were due to blunt trauma and 59% (19/32), to penetrating trauma. Most penetrating injuries were located in the cervical trachea (74%), whereas blunt injuries were more commonly located close to the carina (62%). Fifty-nine percent of the patients required urgent measures to secure the airway. Penetrating injuries were usually diagnosed by clinical findings or at surgical exploration. The diagnosis of blunt injuries was more difficult and required a high index of suspicion and the liberal use of bronchoscopy. The majority of the injuries were repaired primarily using techniques specific to the injury, and most patients returned to their normal activity soon after discharge. Conclusions . A high level of suspicion and the liberal use of bronchoscopy are important in the diagnosis of tracheobronchial injury. A tailored surgical approach is often necessary for definitive repair.

Investigation and control of aspergillosis and other filamentous fungal infections in solid organ transplant recipients.

Filamentous fungal infections are associated with high morbidity and mortality in solid organ transplant patients, and prevention is warranted whenever possible. An increase in invasive aspergillosis was detected among solid organ transplant recipients in our institution during 1991–92. Rates of Aspergillus infection (18.2%) and infection or colonization (42%) were particularly high among lung transplant recipients. Epidemiologic investigation revealed cases to be both nosocomial and community‐acquired, and preventative efforts were directed at both sources. Environmental controls were implemented in the hospital, and itraconazole prophylaxis was given in the early period after lung transplantation. The rate of Aspergillus infection in solid organ transplant recipients decreased from 9.4% to 1.5%, and mortality associated with this disease decreased from 8.2% to 1.8%. The rate of Aspergillus infection or colonization among lung transplant recipients decreased from 42% to 22.5%; nosocomial Aspergillus infection decreased from 9% to 3.2%. Cases of aspergillosis in lung transplant recipients were more likely to be early infections in the pre‐intervention period. Early mortality in lung transplant recipients decreased from 15% to 3.2%. Two cases of dematiaceous fungal infection were detected, and no further cases occurred after environmental controls. The use of environmental measures that resulted in a decrease in airborne fungal spores, as well as antifungal prophylaxis, was associated with a decrease in aspergillosis and associated mortality in these patients. Ongoing surveillance and continuing intervention is needed for prevention of infection in high‐risk solid organ transplant patients.

Clinical results of decompressivedermotomy-fasciotomy**

Seventy-three dermotomy-fasciotomies (DFs) wereperformed in 68 patients from 1986 to 1991. A database record was compiled on each patient. Variables included age, mode of injury, method of initial wound closure, and associated injuries. A multivariate stepwise logistic regression analysis was performed to determine which variables were associated with wound complications. Thirty-eight percent of patients who underwent DF developed wound complications. One hundred percent of those patients with postoperative arterial or graft thrombosis developed wound complications (P DF is frequently necessary in the treatment of patients with compartment syndrome but is associated with significant morbidity. This study suggests that closure of DF wounds utilizing skin graft allows for continued osteofascial decompression while concomitantly minimizing invasive sepsis.

Concomitant weekly cisplatin and thoracic radiotherapy for pancoast tumors of the lung: Pilot experience of the San Antonio cancer institute

Pancoast (superior sulcus tumors) comprise a subset of non–small-cell lung cancers that have a unique clinical presentation by virtue of the locoregional pattern of disease progression. We herein report a brief report on our group’s pilot experience in managing these challenging lung neoplasms with an aggressive concomitant modality approach. These results and those of the recent Southwest Oncology-lead Intergroup prospective phase 2 trial (SWOG-9416/INT-0160) support the use of concomitant chemoradiation followed by an attempt at surgical resection.

Penetrating intrapericardial wounds: Clinical experience with a surgical protocol

BACKGROUND From 1972 to 1977, a treatment protocol was developed at our institution for patients with suspected penetrating intrapericardial wounds. It consists of immediate transport to the operating room, pericardial decompression by subxiphoid pericardial window under local or light general anesthesia in patients in stable condition, and median sternotomy and operative repair with limited use of cardiopulmonary bypass. METHODS The records of 79 consecutive patients with acute penetrating intrapericardial injury who underwent operation from March 1978 to July 1991 were reviewed. There were 59 patients (75%) with stab wounds and 20 (25%) with gunshot wounds. Wound location was as follows: right ventricle, 33 (42%); left ventricle, 28 (35%); multiple sites, 8 (10%); atrium, 5 (6%); and great vessels, 5 (6%). RESULTS Subxiphoid pericardial window was performed under local or light general anesthesia in 53 patients (67%). Cardiopulmonary bypass was required in only 4 patients. Overall mortality was 6%. CONCLUSION Approach to a trauma victim must be systematic. We believe one treatment protocol for patients with suspected penetrating intrapericardial wounds is effective.

Characterization and pharmacokinetic analysis of tacrolimus dispersion for nebulization in a lung transplanted rodent model.

Lung transplantation animal models have been well established and enabled the investigation of a variety of new pharmacotherapeutic strategies for prevention of lung allograft rejection. Direct administration of immunosuppressive agents to the lung is a commonly investigated approach; however, can prove challenging due to the poor solubility of the drug molecule, the tortuous pathways of the lung periphery, and the limited number of excipients approved for inhalation. In this study, we aimed to evaluate a solubility enhancing formulation of tacrolimus for localized therapy in a lung transplanted rat model and determine the extent of drug absorption into systemic circulation. Characterization of the nebulized tacrolimus dispersion for nebulization showed a fine particle fraction (FPF) of 46.1% and a mass median aerodynamic diameter (MMAD) of 4.06 microm. After single dose administration to transplanted and non-transplanted rats, a mean peak transplanted lung concentration of 399.8+/-29.2 ng/g and mean peak blood concentration of 4.88+/-1.6 ng/mL were achieved. It is theorized that enhanced lung retention of tacrolimus is due to lipophilic associations with bronchial tissue and phospholipid surfactants in lung fluid. These findings indicate that tacrolimus dispersion for nebulization can achieve highly localized therapy for lung transplant recipients.

Testing neonate-infant membrane oxygenators with the University of Texas neonatal pulsatile cardiopulmonary bypass system in vitro

Neurologic complications are already well documented after cardiopulmonary bypass (CPB) procedures in neonates and infants. Physiologic pulsatile flow CPB systems may be the alternative to the currently used steady-flow CPB circuits. In addition to the pulsatile pump, a membrane oxygenator should be chosen carefully, because only a few membrane oxygenators are suitable for physiologic pulsatile flow. We have tested four different types of neonate-infant membrane oxygenators for physiologic pulsatility with The University of Texas neonate-infant pulsatile CPB system in vitro. Evaluation criteria were based on mean ejection time, extracorporeal circuit (ECC) pressure, and upstroke of dp/dt. The results suggested that the Capiox 308 hollow-fibre membrane oxygenator produced the best physiologic pulsatile waveform according to the ejection time, ECC pressure, and the upstroke of dp/dt. The Minimax Plus and Masterflo Infant hollow-fibre membrane oxygenators also produced adequate pulsatile flow. Only the Variable Prime Cobe Membrane Lung (VPCML) Plus flat-sheet membrane oxygenator failed to reach the criteria for physiologic pulsatility. Depending on the oxygenator used, the lowest priming volume of the infant CPB circuit was 415 ml and the highest 520 ml.

Effect of inhaled tacrolimus on ischemia reperfusion injury in rat lung transplant model

OBJECTIVE Systemic tacrolimus therapy has been shown to protect against lung ischemia-reperfusion injury in animal models. We sought to investigate on a functional and cellular level if inhaled nanoparticle tacrolimus administered to the donor lung before procurement could similarly attenuate ischemia-reperfusion injury after lung transplant. METHODS An isogenic orthotopic rat model of single left lung transplant was used. Donor animals were pretreated with inhaled tacrolimus (treatment group) or inhaled lactose (controls) before lung procurement. Lung grafts were subjected to 3 hours of cold ischemia followed by 4 hours of reperfusion after graft implantation. Recipient animal arterial blood gas measurement and isograft wet to dry weight ratios were obtained. Macrophage, neutrophil, and T-cell accumulation and activation in lung isografts, including γδ T-cell, T-helper, and cytotoxic T-cell subtypes were analyzed by flow cytometry. Tacrolimus levels were measured in the lung isograft using liquid chromatography/mass spectrometry. Isograft cytokine levels were measured with commercial enzyme-linked immunosorbent assay and microbead array kits. RESULTS Oxygenation in treatment group animals was significantly higher than in controls. The presence of macrophages, neutrophils, and all T-cell subtypes in the isografts as well as isograft levels of inflammatory cytokines were all less in the treatment group versus controls, although no single variable achieved statistical significance. CONCLUSIONS Inhaled nanoparticle tacrolimus treatment of lung donors is associated with an attenuation of ischemia-reperfusion injury on a functional and cellular level in lung transplant.

The successful use of cardiopulmonary support for a transected bronchus.

A 20-year-old male was involved in a motor vehicle accident and computed tomography revealed a completely transected right mainstem bronchus. An Emergency Department (ED) right anterior thoracotomy was necessary soon after arrival at our institution secondary to acute desaturation that was unresponsive to ventilator and chest tube management. This allowed direct intubation and ventilation of the right middle and lower lobes directly through the thoracotomy incision, which stabilized the patient for transport to the operating room. Once there, percutaneous cardiopulmonary support (CPS) was initiated to allow primary surgical repair of the transected bronchus. Post surgery, the patient was transported to the surgical intensive care unit on CPS which he required for an additional two days. The patient eventually did well and was discharged home. To our knowledge this is the first successful reported case of using the Avalon Elite dual lumen veno-venous cannula for CPS in a patient with complete right main-stem bronchus transection and bilateral pulmonary contusions.

Dual-inflow great vessel aneurysm: Delayed presentation after penetrating trauma

Aneurysms constitute uncommon sequelae of injuries to the thoracic outlet. Most such aneurysms are secondary to blunt trauma and usually involve the great vessels at their take-off from the aortic arch. Penetrating injuries are more often identified in the more distal vessels and only very rarely present as pseudoaneurysms. Reported here is a single case of a chronic posttraumatic pseudoaneurysm arising from both the right common carotid artery and the right subclavian artery. The workup and surgical approach provide practical lessons, complemented with illustrations that aid in the understanding of the case. It is an unusual case because of the dual-inflow nature of the aneurysm.