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Background and Objectives: Neuromuscular relaxants are essential during general anesthesia for several procedures. Classical anesthesiology literature indicates that the use of neuromuscular blockade in thoracic surgery may be deleterious in patients in lateral decubitus position in one-lung ventilation. The primary objective of our study was to compare respiratory function according to the degree of patient neuromuscular relaxation. Secondary, we wanted to check that neuromuscular blockade during one-lung ventilation is not deleterious., Methods: A prospective, longitudinal observational study was made in which each patient served as both treated subject and control. 76 consecutive patients programmed for lung resection surgery in Gregorio Marañon Hospital along the year of 2013 who required one-lung ventilation in lateral decubitus were included. Ventilator data, hemodynamic parameters were registered in different moments according to train-of-four response (intense, deep and moderate blockade) during one-lung ventilation., Results: Peak, plateau and mean pressures were significantly lower during the intense and deep blockade. Besides, compliance and peripheral oxygen saturation were significantly higher in those moments. Heart rate was significantly higher during deep blockade. No mechanical ventilation parameters were modified during measurements., Conclusions: Deep neuromuscular blockade attenuates the poor lung mechanics observed during one-lung ventilation., (Copyright © 2016 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.)

Background: Measurement of inflammatory mediators in bronchoalveolar lavage (BAL) during lung resection surgery with periods of one-lung ventilation (OLV) has revealed an intense local pulmonary response. The role of each lung in the inflammation that occurs during this procedure has never been investigated., Objective(s): The primary objective of our study was to compare the inflammatory response in the dependent lung with that of the nondependent lung by measuring inflammatory markers in BAL. Our secondary objective was to assess the behaviour of these inflammatory mediators in patients with and without postoperative pulmonary complications (PPCs)., Design: A prospective, observational study., Setting: Department of Anaesthesiology in a university hospital., Patients: Forty-six consecutive patients undergoing lung resection surgery., Intervention(s): BAL samples were taken from dependent and nondependent lung 10 min before initiating OLV and at the end of OLV (once two-lung ventilation was established). All patients were followed up until 30 days after surgery., Main Outcome Measures: The concentration of cytokines [interleukin (IL)-1, IL-2, IL-6, IL-10, tumour necrosis factor-alpha (TNF-α)], nitric oxide, carbon monoxide and matrix metalloproteinase 2 (MMP-2) was analysed in both lungs before and after OLV. PPCs were recorded., Results: In BAL fluid, all measured biomarkers, apart from IL-10, were significantly greater (P < 0.05) at the end of OLV than those obtained before OLV, both for the dependent and nondependent lung. The increase in measured biomarkers was similar in both lungs. Eight patients developed PPC. Patients who developed PPC had higher levels of TNF-α (P < 0.05) in BAL from the nondependent lung before and after OLV than patients who did not have PPC. Patients who developed PPC had a smaller increase in MMP-2 levels (P < 0.05) in the dependent lung than patients who did not have PPC., Conclusion: In lung resection surgery, the inflammatory response is similar in both lungs. However, the greater increase in TNF-α levels in the nondependent lung and the smaller increase of MMP-2 concentration in the dependent lung may increase the susceptibility to develop PPC.

Background: Lung resection surgery is associated with an inflammatory reaction. The use of 1-lung ventilation (OLV) seems to increase the likelihood of this reaction. Different prophylactic and therapeutic measures have been investigated to prevent lung injury secondary to OLV. Lidocaine, a commonly used local anesthetic drug, has antiinflammatory activity. Our main goal in this study was to investigate the effect of IV lidocaine on tumor necrosis factor α (TNF-α) lung expression during lung resection surgery with OLV., Methods: Eighteen pigs underwent left caudal lobectomy. The animals were divided into 3 groups: control, lidocaine, and sham. All animals received general anesthesia. In addition, animals in the lidocaine group received a continuous IV infusion of lidocaine during surgery (1.5 mg/kg/h). Animals in the sham group only underwent thoracotomy. Samples of bronchoalveolar lavage (BAL) fluid and plasma were collected before initiation of OLV, at the end of OLV, at the end of surgery, and 24 hours after surgery. Lung biopsy specimens were collected from the left caudal lobe (baseline) before surgery and from the mediastinal lobe and the left cranial lobe 24 hours after surgery. Samples were flash-frozen and stored to measure levels of the following inflammatory markers: interleukin (IL) 1β, IL-2, IL-10, TNF-α, nuclear factor κB, monocyte chemoattractant protein-1, inducible nitric oxide synthase, and endothelial nitric oxide synthase. Markers of apoptosis (caspase 3, caspase 9, Bad, Bax, and Bcl-2) were also measured. In addition, levels of metalloproteinases and nitric oxide metabolites were determined in BAL fluid and in plasma samples. A nonparametric test was used to examine statistical significance., Results: OLV caused lung damage with increased TNF-α expression in BAL, plasma, and lung samples. Other inflammatory (IL-1β, nuclear factor κB, monocyte chemoattractant protein-1) and apoptosis (caspase 3, caspase 9, and BAX) markers were also increased. With the use of IV lidocaine there was a significant decrease in the levels of TNF-α in the same samples compared with the control group. Lidocaine administration also reduced the inflammatory and apoptotic changes observed in the control group. Hemodynamic values, blood gas values, and airway pressure were similar in all groups., Conclusions: Our results suggest that lidocaine can prevent OLV-induced lung injury through reduced expression of proinflammatory cytokines and lung apoptosis. Administration of lidocaine may help to prevent lung injury during lung surgery with OLV.

Objective: The purpose of this study was to investigate the relationship between the ventilatory mode used during one-lung ventilation (OLV) and intraoperative and early postoperative arterial oxygenation in patients undergoing thoracic surgery., Methods: A prospective, randomized clinical trial., Setting: A tertiary care university hospital single institution., Participants: One hundred ten patients scheduled for thoracic surgery with at least 1 hour of OLV., Interventions: Patients were prospectively randomized into 2 groups depending on the ventilatory mode used during OLV: volume-controlled ventilation (VCV) or pressure-controlled ventilation (PCV). In VCV, the authors used a tidal volume (Vt) of 8 mL/kg and in the PCV group an inspiratory pressure to provide a tidal volume of 8 mL/kg., Measurements and Main Results: Airway pressures and arterial blood gases were obtained at 20, 30, and 40 minutes after OLV. The authors recorded the ratio of arterial oxygen tension to inspired oxygen fraction (PaO(2)/F(I)O(2)) at 4 hours (RU1) and 24 hours (RU2) after surgery. During OLV, there were no differences in arterial oxygenation, airway plateau pressure, and mean pressure between groups, although peak pressure was higher in the VCV group (p < 0.01). The PaO(2)/F(I)O(2) ratio at RU1 was 312.6 +/- 106 in the VCV group and 322.1 +/- 104. In the PCV group at RU2, it was 402.4 +/- 105 and 389.6 +/- 114, respectively, and there were no significant differences between the groups., Conclusions: In patients undergoing thoracic surgery, the use of PCV compared with VCV during OLV with the same Vt of 8 mL/kg does not affect arterial oxygenation during OLV or early postoperative oxygenation.

Objective: The objective of the present study was to investigate respiratory and hemodynamic changes by measuring continuous cardiac output, cardiac filling, and stroke volume variation after lung recruitment in thoracic surgery., Design: A prospective, observational study., Setting: A tertiary care university hospital single institution., Participants: Forty patients undergoing thoracotomy for lung resection with at least 1 hour of one-lung ventilation (OLV)., Interventions: During OLV, an alveolar recruitment maneuver (ARM) was performed., Measurements and Main Results: Based on Edwards Vigileo/FloTrac system (Edwards Lifesciences, Irvine, CA), the arterial pressure-based cardiac output, cardiac index, systemic vascular resistance, stroke volume variation, and central venous oxygen saturation were recorded immediately before the maneuver and 1, 2, 3, 4, 5, and 10 minutes after the maneuver. Stroke volume variation was the parameter most affected during and after the maneuver; it increased to 50% and 40% in the first and second minute, respectively (p < 0.01). The cardiac index was also affected and decreased 9.4% (p < 0.05) in the first minute after the maneuver. ScvO2 decreased significantly during the first 2 minutes (7% and 6.5%, respectively). However, after 3 minutes, all values recorded were similar to prerecruitment values. The PaO2 and PcvO2 from samples taken 10 minutes after the maneuver improved considerably with respect to the values before alveolar recruitment., Conclusions: The authors concluded that during open-chest surgery with OLV, an ARM effectively improved oxygenation without inducing important circulatory changes.

Objective: To compare the effects that the use of general intravenous anesthesia (propofol-fentanyl) (GA) or general anesthesia combined with thoracic epidural anesthesia with meperidine (TEA-M) may have on arterial oxygenation during one-lung ventilation (OLV)., Design: Prospective., Setting: Tertiary care hospital., Participants: Seventy-two patients undergoing OLV for thoracic surgery., Interventions: Patients were prospectively randomized into two groups: GA (n = 37) fentanyl, propofol, rocuronium anesthesia was used; and group TEA-M (n = 35) were anesthetized with propofol, rocuronium and thoracic epidural meperidine (2 mg/kg in 10-12 mL) administered before anesthetic induction. A double-lumen endotracheal tube was inserted, and mechanical ventilation with 100% oxygen was used during study. Mean arterial pressure, heart rate and arterial and venous blood gases were recorded with the patients in the lateral decubitus position in three phases: during two-lung ventilation (TLV), 15 and 30 minutes after beginning OLV (OLV + 15 and OLV + 30 respectively). The authors measured arterial and venous central oxygen tension, arterial and venous central oxygen saturation, arterial and venous central oxygen content and venous admixture percentage (Qs/Qt%)., Measurements and Main Results: There were no statistical differences between the two groups for PaO(2) during OLV + 15 (GA = 165 mmHg, TEA-M = 153 mmHg) and OLV + 30 (GA = 176 mmHg, TEA-M = 158 mmHg); and with values for Qs/Qt%., Conclusions: It is concluded that GA combined with TEA-M (2 mg/kg) do not affect arterial oxygenation during OLV in thoracic surgery.