Video-assisted thoracic surgery attenuates perioperative oxidative stress response in lung cancer patients: a preliminary study

Objectives: Reactive oxygen species (ROS) function as key metabolites that can impair biological processes. The aim of this preliminary study was to assess the perioperative oxidative changes in lung cancer surgery.Methods: We measured the levels of blood hydroperoxides, a type of ROS, as an index of oxidative injury to cellular components, as well as the plasma ferric-reducing ability as an index of total antioxidant potential in 32 lung cancer patients. Hydroperoxides were measured by the levels of diacron reactive oxygen metabolites (d-ROMs). The antioxidant potential was determined by the biological antioxidant potential (BAP), which represents the levels of endogenous antioxidant enzymes.Results: Lung cancer patients had slightly affected oxidative stress before surgery. The d-ROM and BAP levels after surgery and were significantly decreased than before surgery (p< 0.001) and the levels recovered preoperatively at third postoperative day. The d-ROM level in video-assisted surgery group (n=17) was significantly decreased than those in thoracotomy group (n=15) at third and seventh post-operative day (p < 0.001, and < 0.02).Conclusions: Lung cancer patients had already exposed oxidative stress before surgery and surgical intervention also generates large amounts of ROS. Video-assisted thoracic surgery can reduce the ROS compared to the standard thoractomy

Early-phase changes of extravascular lung water index as a prognostic indicator in acute respiratory distress syndrome patients

Background: The features of early-phase acute respiratory distress syndrome (ARDS) are leakage of fluid into the extravascular space and impairment of its reabsorption, resulting in extravascular lung water (EVLW) accumulation. The current study aimed to identify how the initial EVLW values and their change were associated with mortality. Methods: This was a post hoc analysis of the PiCCO Pulmonary Edema Study, a multicenter prospective cohort study that included 23 institutions. Single-indicator transpulmonary thermodilution-derived EVLW index (EVLWi) and conventional prognostic factors were prospectively collected over 48 h after enrollment. Associations between 28-day mortality and each variable including initial (on day 0), mean, maximum, and Δ (subtracting day 2 from day 0) EVLWi were evaluated. Results: We evaluated 192 ARDS patients (median age, 69 years (quartile, 24 years); Sequential Organ Failure Assessment (SOFA) score on admission, 10 (5); all-cause 28-day mortality, 31%). Although no significant differences were found in initial, mean, or maximum EVLWi, Δ-EVLWi was significantly higher (i.e., more reduction in EVLWi) in survivors than in non-survivors (3.0 vs. ?0.3 mL/kg, p = 0.006). Age, maximum, and Δ-SOFA scores and Δ-EVLW were the independent predictors for survival according to the Cox proportional hazard model. Patients with Δ-EVLWi > 2.8 had a significantly higher incidence of survival than those with Δ-EVLWi ? 2.8 (log-rank test, χ2 = 7.08, p = 0.008). Conclusions: Decrease in EVLWi during the first 48 h of ARDS may be associated with 28-day survival. Serial EVLWi measurements may be useful for understanding the pathophysiologic conditions in ARDS patients. A large multination confirmative trial is required

Infectious Episodes Lead to the Oxidative Stress Response after Lung Transplantation

Objective: Challenging differential diagnosis Background: Reactive oxygen species function as key metabolites that can impair biological processes. In lung transplantation, severe oxidative stress is expected when ischemia/reperfusion injury, acute allograft rejection, and various infections occur. Case Report: Two clinical cases in which serial measurements of the oxidative stress response (levels of diacron-reactive oxygen metabolites) were taken during hospitalization using a Free Radical Elective Evaluator are reported. In the first case, a 30-year-old man underwent right single lung transplantation for juvenile pulmonary emphysema. Immunosuppression was maintained using tacrolimus, mycophenolate mofetil, and steroid. The oxidative stress response fluctuated significantly (p<0.01) during the infections caused by bronchial stenosis compared to the stable condition. No acute rejection was seen during hospitalization. In the second case, a 44-year-old woman underwent right single lung transplantation for lymphangioleiomyomatosis. Immunosuppression was maintained by the same regimen as in case 1. The patient’s postoperative course was uneventful, and there was no allograft rejection or infection. The oxidative stress response remained at the non-stress level. Conclusions: The oxidative stress response was measured by the levels of diacron-reactive oxygen metabolites in lung transplantation. High oxidative stress responses were seen during exposure to infections. This might become a noninvasive marker of complications after transplantation

Balance of the prooxidant and antioxidant system is associated with mortality in critically ill patients

It is well known that oxidative stress causes certain diseases and organ damage. However, roles of oxidative stress in the acute phase of critical patients remain to be elucidated. This study aimed to investigate the balance of oxidative and antioxidative system and to clarify the association between oxidative stress and mortality in critically ill patients. This cohort study enrolled 247 patients transported to our emergency department by ambulance. Blood was drawn on hospital arrival, and serum derivatives of reactive oxidant metabolites (dROMs, oxidative index) and biological antioxidant potential (BAP, antioxidative index) were measured. Modified ratio (MR) is also calculated as BAP/dROMs/7.51. There were 197 survivors and 50 non-survivors. In the non-survivors, dROMs were significantly lower (274 vs 311, p<0.01), BAP was significantly higher (2,853 vs 2,138, p<0.01), and MR was significantly higher (1.51 vs 0.92, p<0.01) compared to those in the survivors. The AUC of MR was similar to that for the APACHE II score. Contrary to our expectations, higher BAP and lower dROMs were observed on admission in non-survivors. This may suggest that the antioxidative system is more dominant in the acute phase of severe insults and that the balance toward a higher antioxidative system is associated with mortality

Relationship between extravascular lung water and severity categories of acute respiratory distress syndrome by the Berlin definition

Introduction: The Berlin definition divides acute respiratory distress syndrome (ARDS) into three severity categories. The relationship between these categories and pulmonary microvascular permeability as well as extravascular lung water content, which is the hallmark of lung pathophysiology, remains to be elucidated. The aim of this study was to evaluate the relationship between extravascular lung water, pulmonary vascular permeability, and the severity categories as defined by the Berlin definition, and to confirm the associated predictive validity for severity.Methods: The extravascular lung water index (EVLWi) and pulmonary vascular permeability index (PVPI) were measured using a transpulmonary thermodilution method for three consecutive days in 195 patients with an EVLWi of ≥10 mL/kg and who fulfilled the Berlin definition of ARDS. Collectively, these patients were seen at 23 ICUs. Using the Berlin definition, patients were classified into three categories: mild, moderate, and severe.Results: Compared to patients with mild ARDS, patients with moderate and severe ARDS had higher acute physiology and chronic health evaluation II and sequential organ failure assessment scores on the day of enrollment. Patients with severe ARDS had higher EVLWi (mild, 16.1; moderate, 17.2; severe, 19.1; P <0.05) and PVPI (2.7; 3.0; 3.2; P <0.05). When categories were defined by the minimum PaO2/FIO2ratio observed during the study period, the 28-day mortality rate increased with severity categories: moderate, odds ratio: 3.125 relative to mild; and severe, odds ratio: 4.167 relative to mild. On independent evaluation of 495 measurements from 195 patients over three days, negative and moderate correlations were observed between EVLWi and the PaO2/FIO2ratio (r = -0.355, P<0.001) as well as between PVPI and the PaO2/FIO2ratio (r = -0.345, P <0.001). ARDS severity was associated with an increase in EVLWi with the categories (mild, 14.7; moderate, 16.2; severe, 20.0; P <0.001) in all data sets. The value of PVPI followed the same pattern (2.6; 2.7; 3.5; P <0.001).Conclusions: Severity categories of ARDS described by the Berlin definition have good predictive validity and may be associated with increased extravascular lung water and pulmonary vascular permeability. Trial registration: UMIN-CTR ID UMIN000003627