Efficacy of a Low-Tidal Volume Ventilation Strategy to Prevent Reperfusion Lung Injury after Pulmonary Thromboendarterectomy.

RATIONALE: Reperfusion lung injury is a postoperative complication of pulmonary thromboendarterectomy that can significantly affect morbidity and mortality. Studies in other postoperative patient populations have demonstrated a reduction in acute lung injury with the use of a low-tidal volume (Vt) ventilation strategy. Whether this approach benefits patients undergoing thromboendarterectomy is unknown. OBJECTIVES: We sought to determine if low-Vt ventilation reduces reperfusion lung injury in patients with chronic thromboembolic pulmonary hypertension undergoing thromboendarterectomy. METHODS: Patients undergoing thromboendarterectomy at one center were randomized to receive either low (6 ml/kg predicted body weight) or usual care Vts (10 ml/kg) from the initiation of mechanical ventilation in the operating room through Postoperative Day 3. The primary endpoint was the onset of reperfusion lung injury. Secondary outcomes included severity of hypoxemia, days on mechanical ventilation, and intensive care unit and hospital lengths of stay. MEASUREMENTS AND MAIN RESULTS: A total of 128 patients were enrolled and included in the analysis; 63 were randomized to the low-Vt group and 65 were randomized to the usual care group. There was no statistically significant difference in the incidence of reperfusion lung injury between groups (32%, n=20 in the low-Vt group vs. 23%, n=15 in the usual care group; P=0.367). Although differences were noted in plateau pressures (17.9 cm H2O vs. 20.1 cm H2O, P<0.001) and peak inspiratory pressures (20.4 cm H2O vs. 23.0 cm H2O, P<0.001) between the low-Vt and usual care groups, respectively, mean airway pressures, PaO2/FiO2, days on mechanical ventilation, and ICU and hospital lengths of stay were all similar between groups. CONCLUSIONS: In patients with chronic thromboembolic pulmonary hypertension undergoing pulmonary thromboendarterectomy, intra- and postoperative ventilation using low Vts (6 mg/kg) compared with usual care Vts (10 mg/kg) does not reduce the incidence of reperfusion lung injury or improve clinical outcomes. Clinical trial registered with www.clinicaltrials.gov (NCT00747045).

Tumors of the mediastinum.

Tumors of the mediastinum represent a wide diversity of disease states. The location and composition of a mass is critical to narrowing the differential diagnosis. The most common causes of an anterior mediastinal mass include the following: thymoma; teratoma; thyroid disease; and lymphoma. Masses of the middle mediastinum are typically congenital cysts, including foregut and pericardial cysts, while those that arise in the posterior mediastinum are often neurogenic tumors. The clinical sequelae of mediastinal masses can range from being asymptomatic to producing symptoms of cough, chest pain, and dyspnea. This article will review the anatomy of the mediastinum as well as the different clinical, radiographic, and prognostic features, and therapeutic options of the most commonly encountered masses.

Misdiagnosis of schizophrenia in a patient with psychotic symptoms.

OBJECTIVE: A case is presented of a 37-year-old black woman with a 5-year history of a chronic psychotic illness, diagnosed as schizophrenia, who presented to the emergency room complaining of a severe headache, while appearing confused and experiencing visual and auditory hallucinations. The purpose of this case study is to illustrate the way in which the appellation of schizophrenia can be misapplied in a patient with a complicated medical history and poor follow-up evaluation and treatment. BACKGROUND: Patients with active psychosis are frequently unable to provide a coherent or comprehensive medical history. In the absence of obvious indications to the contrary, a diagnosis of a primary psychiatric illness is often assumed, especially if this label has been applied in the past. However, the differential diagnosis of psychosis is extensive. METHODS: This patient was given a complete psychiatric and neurologic evaluation, and aspects of the history that had been lost or ignored were uncovered and reevaluated. RESULTS: A diagnosis other than schizophrenia was made and another treatment, other than antipsychotic drugs, was initiated. The patient responded rapidly with improved cognitive function and resolution of her psychotic symptoms. CONCLUSIONS: This case serves to illustrate how the absence of a careful clinical assessment and historical case review, in patients who have been previously labeled as schizophrenic, can perpetuate misdiagnoses and inappropriate treatments. It highlights the importance, especially in patients with an incomplete medical history, of ruling out all organic causes of psychosis to avoid inappropriately labeling someone as having a psychiatric illness.