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Study Objectives: Bronchoscopy with BAL is being used increasingly in the investigation of acute and chronic lung inflammation. The scope of the acute phase response induced by the procedure is not fully evaluated. The purpose of the study is to characterize the acute phase response induced by bronchoscopy with BAL., Design: Observational study., Setting: A human study research facility., Participants: Normal nonsmoking volunteers., Intervention: A total of 28 subjects were recruited. Under local anesthesia, the subjects underwent bronchoscopy with a videofiberoptic bronchoscope. One subsegment of the lingular segment of the left upper lobe and the right middle lobe were lavaged each with 170 to 270 mL of sterile normal saline solution., Measurements and Results: CBC count, serum levels of indexes of iron homeostasis, fibrinogen, C-reactive protein (CRP), and plasma mediators related to neutrophil migration and endothelial cell activation, including interleukin (IL)-8, angiotensin converting enzyme (ACE), soluble intercellular adhesion molecule (sICAM)-1, and nitrite/nitrate, were measured. Measurements of these plasma markers were done immediately before, immediately after, and 24 h after bronchoscopy. Changes in acute phase response were detected primarily at 24 h after the procedure. WBCs, primarily neutrophils, increased by approximately 50%. Fibrinogen increased by 25% while CRP increased by more than sevenfold. Serum ferritin increased by 25% while serum iron, total iron-binding capacity, and transferrin saturation decreased, indicating dysregulation of iron homeostasis. There were no changes in IL-8, ACE, sICAM-1, or nitrite/nitrate plasma levels., Conclusions: Bronchoscopy with BAL induces a variety of acute phase responses that includes peripheral neutrophilia, dysregulation of iron homeostasis, and increased levels of fibrinogen and CRP. Human research that employs BAL may need to consider the biological effects induced by the procedure-related acute phase response.

Background: Bronchoscopy with biopsy and BAL is being performed increasingly in patients with COPD as a research tool. Previous reports have shown these procedures to be safe in asthmatic patients, but there is little safety data specific to COPD., Methods: We studied 57 patients with COPD (11 women and 46 men; median FEV(1), 1.2 L [range, 0.64 to 2.69 L]; percent predicted FEV(1), 44.5% [range, 25 to 74.8%]). Eleven patients had mild disease, 28 patients had moderate disease, and 18 patients had severe disease according to British Thoracic Society classification. Ninety-eight bronchoscopies were performed according to American Thoracic Society guidelines: 68 procedures with endobronchial biopsy and BAL and 30 procedures with biopsy alone. Controlled oxygen was administered via nasal cannula, and pulse oximetry and vital signs were monitored., Results: Five adverse events occurred. One patient in the moderate-disease group had severe bronchospasm requiring 4 days of inpatient treatment. One patient in the severe-disease group had a pneumothorax requiring 7 days of inpatient treatment. There were three episodes of hemoptysis, two with pleuritic pain (in the BAL group) that settled without intervention. No deaths or prolonged morbidity were observed. We found a 2.0% incidence of adverse events requiring hospital treatment and a 3.1% incidence of minor hemoptysis requiring no intervention., Conclusions: Bronchoscopy, biopsy, and BAL can be performed safely in patients with COPD, including those with severe disease, provided careful assessment is performed and guidelines are adhered to.

Background: Despite increasing knowledge about partial liquid ventilation (PLV), the optimal dose of perfluorocarbon (PFC) is not yet established. Because there exist normal regions in the lung with ARDS and because PLV in the normal lung results in worsened gas exchange, we postulated that the optimal dose of PFC for PLV may be less than the functional residual capacity (FRC) dose in the lung with limited disease., Design and Setting: Animal study at the Asan Institute for Life Sciences, Seoul, Korea., Subjects: Twelve rabbits in which dependent lung-dominant lung injury was created by a modified saline solution lavage., Interventions: PLV performed at six different doses of perfluorodecalin in sequence (3, 6, 9, 12, 15, and 18 mL/kg every 15 min)., Measurements and Results: Our modified saline solution lavage induced atelectasis and hemorrhage confined to the dependent lung with severe hypoxia (PaO(2)/fraction of inspired oxygen = 37 +/- 6 mm Hg). Peak airway pressure (Ppeak) and inspiratory pause pressure (Ppause) with PLV were lower at doses of 3 to 15 mL/kg (all p < 0.05), but not different at a dose of 18 mL/kg, when compared with gas ventilation. Ppeak increased at doses of 12, 15, and 18 mL/kg, when each was compared with the preceding PFC dose. At increasing PFC doses, the change in the elastic component of airway pressure (Ppause after minus Ppause before) was negative until the dose of 9 mL/kg, but was positive at doses of 12 mL/kg and above. The change in the resistive component ([Ppeak minus Ppause] after minus [Ppeak minus Ppause] before) was negative until the dose of 6 mL/kg, but was positive at the dose > or = 9 mL/kg., Conclusion: Respiratory mechanics during PLV for dependent lung-dominant lung injury were optimal at a PFC dose less than the FRC.

Study Objectives: To determine the effects of different levels of positive end-expiratory pressure (PEEP) during partial liquid ventilation (PLV) on gas exchange, lung compliance, and end-expiratory lung volume (EELV)., Design: Prospective animal study., Setting: Animal physiology research laboratory., Subjects: Nine piglets., Interventions: Animals underwent saline solution lavage to produce lung injury. Perflubron was instilled via the endotracheal tube in a volume estimated to represent functional residual capacity. The initial PEEP setting was 4 cm H(2)O, and stepwise changes in PEEP were made. At 30-min intervals, the PEEP was increased to 8, then 12, then decreased back down to 8, then 4 cm H(2)O., Measurements and Results: After 30 min at each level of PEEP, arterial blood gases, aortic and central venous pressures, heart rates, dynamic lung compliance, and changes in EELV were recorded. Paired t tests with Bonferroni correction were used to evaluate the data. There were no differences in heart rate or mean BP at the different PEEP levels. CO(2) elimination and oxygenation improved directly with the PEEP level and mean airway pressure (Paw). Compliance did not change with increasing PEEP, but did increase when PEEP was lowered. EELV changes correlated directly with the level of PEEP., Conclusions: As previously reported during gas ventilation, oxygenation and CO(2) elimination vary directly with PEEP and proximal Paw during PLV. EELV also varies directly with PEEP. Dynamic lung compliance, however, improved only when PEEP was lowered, suggesting an alteration in the distribution of perflubron due to changes in pressure-volume relationships.

Study Objectives: Asymptomatic HIV-infected individuals are increasingly recruited for studies involving invasive procedures such as bronchoscopy. We sought to determine the response to and outcome of a request for a research bronchoscopy in HIV-positive individuals with no respiratory disease, and whether this would adversely affect future decisions to have a medically indicated bronchoscopy., Design and Setting: Prospective, semistructured, questionnaire-based study in a London teaching hospital HIV outpatient clinic., Participants: One hundred and seven consecutive HIV-infected eligible individuals. Thirty-one healthy volunteers served as a control group for the subjective response to bronchoscopy., Main Outcome Measures: Subjects' attitudes and responses to requests for bronchoscopy and subsequent behavior when they required medically indicated bronchoscopy., Results: Seventy-five patients (70%) agreed to the procedure in principle, predominantly for altruistic reasons. Thirty-nine subjects underwent bronchoscopy. Five percent found it worse than expected; and 79% agreed to another research bronchoscopy (performed in 11 subjects approximately 2 years later). All patients said they would undergo bronchoscopy again for diagnostic purposes (required in seven during the study). When compared to a healthy volunteer population within the same study, postbronchoscopy symptoms were similar in frequency although somewhat different in nature. Subjects felt that a clear explanation of what was involved enhanced their participation in this research., Conclusions: Invasive research procedures such as bronchoscopy can be performed and are repeatable in a healthy HIV-infected population. Performance of procedures for research purposes does not appear to adversely affect future health-care decisions.

Study Objective: To assess the influence of fiberbronchoscopic alveolar lavage on hemodynamics, right ventricular function, and plasma atrial natriuretic peptide (ANP) concentrations in critically ill, mechanically ventilated patients., Design: Prospective investigation., Setting: Eight-bed ICU of a university hospital., Patients: Fourteen patients with cardiovascular instability due to a systemic inflammatory response syndrome who were mechanically ventilated., Interventions: Fiberbronchoscopic alveolar lavage after fluid replacement, deep sedation, and paralyzation. Intervention time: 10 min. After inspection of the endobronchial system, one lavage of 40 mL sterile saline solution was instilled in each lung and recovered., Measurements and Results: The fiberbronchoscopic procedure induced a prompt increase in mean pulmonary arterial pressure after 3 min (median[range]: 25 [13 to 39] to 30 [19 to 45] mm Hg, p < 0.05), which increased further after 6 min (34 [17 to 46] mm Hg, p < 0.01). Cardiac index increased simultaneously (4.25 [3.1 to 5.7] to 4.85 [4.3 to 6.9] L/min.m2 after 6 min, p < 0.01), whereas mean arterial pressure and heart rate remained unchanged. Central venous pressure rose from 12 (3 to 18) mm Hg before procedure to 14 (4 to 20) mm Hg after 6 min (p < 0.01). The right ventricular function was measured using a "fast response" ejection fraction thermodilution catheter: end-diastolic volume increased (238 [137 to 358] to 280 [150 to 4ll] mL after 9 min, p < 0.05), as well as stroke volume (88 [54 to 113] to 103 [67 to 153] mL after 9 min, p < 0.01). Right ventricular ejection fraction (37 [25 to 50] %) did not change significantly during the procedure, but the stroke work index was reinforced (8.2 [4.7 to 15.7] to 13.3 [2.4 to 41.3] gm.M/M2 after 6 min, p < 0.01). Plasma c-ANP concentration rose from 135 (24 to 350) to 196.5 (44 to 830 pg/ml after 20 min (p < 0.05). Systemic vascular resistance decreased from 533 (390 to 1,042) to 429 (281 to 684) dynes.s/cm5 after removal of the bronchoscope (p < 0.01)., Conclusions: Although acute pulmonary hypertension was observed during the fiberbronchoscopic procedure, the right ventricular performance did not deteriorate in hemodynamically unstable patients. To maintain a "hyperdynamic cardiovascular state," the right ventricular stroke work was reinforced, presumably by the "Frank-Starling mechanism." We assume that the acute distention of the right side of the heart resulted in elevated ANP concentrations. The marked decrease in systemic vascular resistance might be due to high ANP levels.