Aaron S. Estrera

Early Evacuation of Traumatic Retained Hemothoraces Using Thoracoscopy: A Prospective, Randomized Trial

BACKGROUND Failure to adequately evacuate blood from the pleural space after trauma may result in extended hospitalization and complications such as empyema. METHODS Patients with retained hemothoraces were prospectively randomized to either a second tube thoracostomy (group 1, n = 24) or video-assisted thoracoscopy (VATS) (group 2, n = 15). Group 1 patients in whom additional tube drainage failed were subsequently randomized to either VATS or thoracotomy. Study end points included duration and costs of hospitalization. RESULTS During a 4-year period, 39 patients were entered into the study. Patients in group 2 had shorter duration of tube drainage (2.53 +/- 1.36 versus 4.50 +/- 2.83 days, mean +/- standard deviation; p < 0.02), shorter hospital stay after the procedure (3.60 +/- 1.64 versus 7.21 +/- 5.30 days; p < 0.02), and shorter total hospital stay (5.40 +/- 2.16 versus 8.13 +/- 4.62 days; p < 0.02). Hospital costs were also less in this group (

Changing clinical spectrum of spontaneous pneumothorax

7,689 +/- 3,278 versus

Blunt traumatic rupture of the right hemidiaphragm: experience in 12 patients.

13,273 +/- 8,158; p < 0.02). There was no mortality in either group. No group 2 patient required conversion to thoracotomy. In 10 group 1 patients additional tube placement failed, and this subset was randomized to VATS (n = 5) or thoracotomy (n = 5). No significant difference in clinical outcome was found between these subgroups. CONCLUSIONS In many patients treated only with additional tube drainage (group 1), this therapy fails, necessitating further intervention. Intent to treat with early VATS for retained hemothoraces decreases the duration of tube drainage, the length of hospital stay, and hospital cost. Early intervention with VATS may be a more efficient and economical strategy for managing retained hemothoraces after trauma.

Histologic evidence of the safety of endoscopic saphenous vein graft preparation

The epidemiology and etiology of spontaneous pneumothorax (SP) are shifting away from the predominance of subpleural bleb disease as emphasized by most reports since that of Kjaergaard (Sweden, 1932). We conducted a retrospective review of all patients admitted to a large urban hospital with the diagnosis of SP over the past 8 years. Of 120 patients, 32 had the acquired immunodeficiency syndrome (AIDS) (group 1, 26.6%), 43 patients had classic subpleural bleb disease or chronic obstructive pulmonary disease with blebs (group 2, 35.8%), and 45 patients had nonbleb disease exclusive of AIDS (group 3, 37.5%). These three groups were studied with respect to primary success rates with differing modalities of therapy. Bilateral SP occurred in 34% of group 1 patients, 2% of group 2 patients, and 11% of group 3 patients. The in-hospital mortality was 34% in group 1 compared with 2% in group 2 and 4% in group 3. Thirty-four percent of group 1 patients had recurrent SP compared with 16% of group 2 patients and 8% of group 3 patients. This report describes the changing etiology and epidemiology of SP in a large urban hospital from 1983 to 1991 and represents the largest single-institution report of AIDS-related pneumothorax. Standardized therapy was shown to have predictably favorable results in patients with bleb disease and nonbleb disease exclusive of AIDS. SP in patients with AIDS was associated with a high mortality rate and primary treatment failure; small-bore catheters and nondrainage therapies have a very limited role in these patients.

Avoidance of Esophageal Stricture Following Severe Caustic Burns by the Use of an Intraluminal Stent

In a 9-year period (1972 to 1981), 35 patients with blunt traumatic rupture of the diaphragm were seen in our institution; 12 had involvement of the right hemidiaphragm, an incidence of approximately 34%. In 9 of these 12 patients, the right-sided diaphragmatic injuries were seen soon after the accident (acute), and in 3, late after the accident (chronic). A large diaphragmatic rent, usually 10 cm or more, without any predilection to a specific area of the right hemidiaphragm, was a frequent operative finding. Expectedly, the most common viscus that was injured or herniated through the defect was the liver. Total or nearly total herniation of the liver was noted in 5 patients and partial herniation, in 1. Injury to the juxtahepatic vena cava or hepatic vein, or both, was also encountered in 5 patients. This highly lethal injury accounted for the 3 deaths in the series, all of which were directly related to an uncontrollable exsanguinating hemorrhage from the injured vena cava or hepatic vein. The surgical approach for repair of a ruptured right hemidiaphragm is best individualized. The right thoracotomy approach through a right posterolateral incision is preferred for chronic diaphragmatic injury. It is also our choice in patients in whom acute right-sided injuries are definitively diagnosed and who are hemodynamically stable. This approach not only provided the best exposure of the defect, but also made the repair of associated retrohepatic caval injury surprisingly easy in at least 2 of our patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Systemic arterial air embolism in penetrating lung injury

BACKGROUND Endoscopic methods of saphenous vein procurement have recently been introduced. These techniques have been successful in limiting pain and wound complications, but less information on assessing potential trauma to the harvested vein segment is available. METHODS Fourteen male patients undergoing coronary artery bypass grafting were included in the study. Nine patients underwent endoscopic procurement of saphenous vein whereas 5 patients underwent procurement using standard open techniques. Histologic appearance and immunohistochemical studies (factor VIII:vWF [von Willebrand factor protein] and CD34) of the vein segments were reviewed in a blinded fashion. RESULTS On histologic analysis, no differences in the intima, media, or adventitia were found between endoscopically and conventionally obtained vein segments. Immunohistochemical staining for factor VIII:vWF and CD34 showed no differences between veins harvested by the two techniques. CONCLUSIONS Endoscopic saphenous vein harvesting does not appear to traumatize the vessel wall any more than open techniques. Longitudinal assessment is necessary to evaluate long-term patency in vein grafts procured using this method.

Separating in vivo mechanical stimuli for postpneumonectomy compensation: physiological assessment

The high incidence of stricture following conventional therapy for caustic esophageal injuries prompted us to incorporate the esophageal stenting technique of Reyes and colleagues [3, 5, 6] into our protocol for management of such patients. Four adult patients were treated following severe esophageal burns caused by the ingestion of caustic drain cleaner. The severity of the burn was established by early esophagoscopy. Laparotomy and gastrotomy revealed severe but nontransmural gastric burns. The stent was left in place for 21 days. Antibiotics and corticosteroids were also employed. There have been no late strictures. One patient required laryngeal dilation for adhesions and another, tracheal dilation for subglottic stenosis. Contrast roentgenographic studies and esophageal manometry have revealed nearly normal esophageal function up to 20 months following the injury.

Shifting sources of functional limitation following extensive (70%) lung resection.

Systemic arterial air embolism is frequently unrecognized as a cause of death among patients with isolated penetrating lung injury. Between 1975 and 1983 at Parkland Memorial Hospital, the complication of systemic arterial air embolism developed in 9 patients with penetrating lung injury (six gunshots and three stabbings). Eight patients were either in profound shock or experienced cardiac arrest and all were intubated and on positive-pressure ventilation, frequently on a manual resuscitator bag before or at the time of diagnosis. The diagnosis was made by direct visualization of air in the coronary vessels in all 9 patients, and in 3 air was also aspirated from the left ventricular apex and aortic root. In addition, 5 patients had clinically significant hemoptysis. At operation, only an isolated injury to the lung was found in 7 of the 9 patients. Arterial air embolism is a highly lethal complication; 6 of our patients died, a mortality rate of 66%. Thus, it clearly behooves us to be more alert to the possible occurrence of this complication among all victims of penetrating chest trauma. We must accept that systemic arterial air embolism is an established complication of penetrating lung injury and must recognize that it occurs much more frequently than has been previously reported. Prompt diagnosis coupled with aggressive efforts at cardiopulmonary resuscitation is crucial for successful management of patients with air embolism.

Long-term post-pneumonectomy pulmonary adaptation following all-trans-retinoic acid supplementation

Following right pneumonectomy (PNX), the remaining lung expands and its perfusion doubles. Tissue and microvascular mechanical stresses are putative stimuli for initiating compensatory lung growth and remodeling, but their relative contributions to overall compensation remain uncertain. To temporally isolate the stimuli related to post-PNX lung expansion (parenchyma deformation) from those related to the sustained increase in perfusion (microvascular distention and shear), we replaced the right lung of adult dogs with a custom-shaped inflated prosthesis. Following stabilization of perfusion and wound healing 4 mo later, the prosthesis was either acutely deflated (DEF group) or kept inflated (INF group). Physiological studies were performed pre-PNX, 4 mo post-PNX (inflated prosthesis, INF1), and again 4 mo postdeflation (DEF) compared with controls with simultaneous INF prosthesis (INF2). Perfusion to the remaining lung increased ~76-113% post-PNX (INF1 and INF2) and did not change postdeflation. Post-PNX (INF prosthesis) end-expiratory lung volume (EELV) and lung and membrane diffusing capacities (DL(CO) and DM(CO)) at a given perfusion were 25-40% below pre-PNX baseline. In the INF group EELV, DL(CO) and DM(CO) remained stable or declined slightly with time. In contrast, all of these parameters increased significantly after deflation and were 157%, 26%, and 47%, respectively, above the corresponding control values (INF2). Following delayed deflation, lung expansion accounted for 44%-48% of total post-PNX compensatory increase in exercise DL(CO) and peak O(2) uptake; the remainder fraction is likely attributable to the increase in perfusion. Results suggest that expansion-related parenchyma mechanical stress and perfusion-related microvascular stress contribute in equal proportions to post-PNX alveolar growth and remodeling.

Separating in vivo mechanical stimuli for postpneumonectomy compensation: imaging and ultrastructural assessment

We previously found that, following surgical resection of approximately 58% of lung units by right pneumonectomy (PNX) in adult canines, oxygen-diffusing capacity (Dl(O(2))) fell sufficiently to become a major factor limiting exercise capacity, although the decline was mitigated by recruitment, remodeling, and growth of the remaining lung units. To determine whether an upper limit of compensation is reached following the loss of even more lung units, we measured pulmonary gas exchange, hemodynamics, and ventilatory power requirements in adult canines during treadmill exercise following two-stage resection of approximately 70% of lung units in the presence or absence of mediastinal distortion. Results were compared with that in control animals following right PNX or thoracotomy without resection (Sham). Following 70% lung resection, peak O(2) uptake was 45% below normal. Ventilation-perfusion mismatch developed, and pulmonary arterial pressure and ventilatory power requirements became markedly elevated. In contrast, the relationship of Dl(O(2)) to cardiac output remained normal, indicating preservation of Dl(O(2))-to-cardiac output ratio and alveolar-capillary recruitment up to peak exercise. The impairment in airway and vascular function exceeded the impairment in gas exchange and imposed the major limitation to exercise following 70% resection. Mediastinal distortion further reduced air and blood flow conductance, resulting in CO(2) retention. Results suggest that adaptation of extra-acinar airways and blood vessels lagged behind that of acinar tissue. As more lung units were lost, functional compensation became limited by the disproportionately reduced convective conductance rather than by alveolar diffusion disequilibrium.