Impact of Extended Duration of Polymyxin B-Immobilized Fiber Column Direct Hemoperfusion on Hemodynamics, Vasoactive Substance Requirement, and Pulmonary Oxygenation in Patients with Sepsis: An Observational Study.

INTRODUCTION: Polymyxin B-immobilized fiber column direct hemoperfusion (PMX-DHP) is used for patients with septic shock, and the recommended hemoperfusion period is 2 h. However, it remains unclear whether the optimal duration is 2 h or longer. The purpose of this study was to compare the effects of PMX-DHP between conventional and longer duration of PMX-DHP. METHODS: We retrospectively investigated 103 patients with sepsis who underwent PMX-DHP. The demographic data, routine biochemistry, microbiological data, and primary infection site were reviewed in the medical chart. The acute physiology and chronic health evaluation (APACHE) II score, sequential organ failure assessment (SOFA) score, heart rate, mean arterial pressure (MAP), vasoactive-inotropic score (VIS), and PaO2/FiO2, at baseline and day 3, were compared between the standard group (2 h of PMX-DHP) and the extended group (>2 h of PMX-DHP). RESULTS: Median MAP was significantly lower and median VIS was significantly higher in the extended group at baseline (p < 0.05, 0.01, respectively) There were no significant differences in APACHE II score, SOFA score, and PaO2/FiO2 at baseline between the 2 groups. The increase of MAP and the decrease in VIS from baseline to day 3 were significantly greater in the extended group (p < 0.01, respectively). In the extended group, increase in PaO2/FiO2 was significantly larger in the patients who underwent ≥8 h duration than that in patients who underwent <8 h duration (p < 0.01). The ventilator-free days, the incidence of continuous renal replacement therapy, and the 28-day mortality were not different between the groups. DISCUSSION/CONCLUSIONS: Longer duration of PMX-DHP was associated with the improved MAP and decreased volume of vasoactive-inotropic agents compared with the conventional duration. Eight and longer hours duration of PMX-DHP was associated with the improvement in the pulmonary oxygenation. Further studies are needed to confirm the efficacy of longer duration of PMX-DHP in patients with septic shock.

Unique strategy using a standard double lumen tube during one lung ventilation for successful intraoperative airway management in patients with a giant bulla on the ventilated side: case series.

Giant lung bullae are usually seen in patients with severe chronic obstructive pulmonary disease. Over time, air trapping leads to severe dyspnea and CO2 accumulation. In severe cases, overinflation and rupture of the bulla can cause secondary life-threatening tension pneumothorax. Since positive pressure ventilation exerts deleterious effects on the bulla, general anesthesia is always challenging in patients with giant bullae. We encountered remarkable intraoperative hypercapnia and decreased tidal volume in a 58-year-old male patient with bilateral bullae who underwent right upper bullectomy, due to overinflation of a bulla located in the upper lobe of the ventilated side. Through this experience, to avoid further overinflation, we devised an original, unique and simple airway management strategy using a standard double lumen tube (DLT), which only requires slightly deeper advancement of the DLT to achieve selective lobar blockade during one lung ventilation (OLV). Following the first case, we used this strategy in a 48-year-old male patient who underwent left giant bullectomy, resulting in successful airway management without overinflation during OLV. We recommend our strategy as an option for successful intraoperative airway management during OLV in select bullectomy patients with bilateral giant bullae.

Direct hemoperfusion with polymyxin B-immobilized fibre treatment for acute exacerbation of interstitial pneumonia.

BACKGROUND AND OBJECTIVE: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is recognized as an important cause of mortality. AE has also been reported in patients with other interstitial lung diseases such as idiopathic non-specific interstitial pneumonia (NSIP) and interstitial pneumonia associated with collagen vascular disease (CVD). Current therapies such as high-dose corticosteroid with immunosuppressive agents have provided little benefit for AE. Direct hemoperfusion (DHP) with a polymyxin B-immobilized fibre column (PMX) was originally developed for the treatment of endotoxaemia. Recent clinical reports have suggested beneficial effects of PMX-DHP treatment on patients with AE. In this study, we evaluated the effectiveness and safety of PMX-DHP treatment for patients with AE. METHODS: The clinical records of patients with AE admitted to our intensive care unit between 2006 and 2015 were retrospectively reviewed. RESULTS: Of 54 patients with AE identified from clinical records, 24 were treated with PMX-DHP and 30 were treated without PMX-DHP. The peripheral white blood cell count was significantly decreased (P < 0.001) and the PaO2 /FiO2 (P/F) ratio was significantly improved after PMX-DHP (P = 0.032). While no significant difference was found in the survival proportion between patients treated with and without PMX-DHP, the prognosis of patients with dermatomyositis was significantly improved with the treatment (P = 0.045). Among the PMX-DHP-treated patients, those who received the treatment within 3 days of AE onset tended to have a better prognosis (P = 0.026). CONCLUSION: The early induction of PMX-DHP treatment may improve the prognosis of patients with AE, especially those with dermatomyositis.

Polymyxin B hemoperfusion prevents acute kidney injury in sepsis model.

BACKGROUND: Direct hemoperfusion with a polymyxin B-immobilized column (PMX-DHP) adsorbs endotoxin and has been used for the treatment of septic shock. Yet, the mechanisms by which PMX-DHP acts on acute kidney injury are only partially understood. MATERIALS AND METHODS: Rats were anesthetized, tracheostomized, and placed on mechanical ventilation. The animals were randomized to three groups: a cecal ligation and puncture (CLP) + dummy-DHP group (n = 10), a CLP + PMX-DHP group (n = 10), and a sham group (n = 4). Four hours after CLP, a dummy-DHP or PMX-DHP was performed for 1 h. The heart rate, mean arterial pressure, arterial blood gases, and plasma concentrations of creatinine, lactate, potassium, interleukin (IL)-6, and IL-10 were measured at 0 h and 8 h. Eight hours after CLP, the kidney was harvested, and histopathologic examination was performed. The expressions of cleaved poly (ADP-ribose) polymerase (PARP) and nuclear factor (NF)-κB p65 were examined by immunohistochemistry. A terminal deoxynucleotide transferase dUTP nick-end labeling assay was performed to detect apoptotic nuclei in kidney sections. RESULTS: PMX-DHP maintained hemodynamics and the acid-base balance and significantly (P < 0.05) decreased the plasma concentrations of lactate, creatinine, potassium, IL-6, and IL-10 compared with dummy-DHP. PMX-DHP significantly (P < 0.001) attenuated the expressions of cleaved PARP and NF-κB p65 in renal tubular cells and renal tubular cell apoptosis compared with dummy-DHP. CONCLUSIONS: These findings suggest that PMX-DHP may protect against acute kidney injury not only by inhibiting the NF-κB signaling pathway but also by preventing renal tubular cell apoptosis.

Atrial natriuretic peptide attenuates kidney-lung crosstalk in kidney injury.

BACKGROUND: Renal ischemia-reperfusion injury (IRI) is a common cause of acute kidney injury after cardiovascular surgery, which in turn deteriorates oxygenation. Atrial natriuretic peptide (ANP) has natriuretic, diuretic, and anti-inflammatory effects. To elucidate whether renal IRI induces inflammation in the kidney and lung and ANP attenuates kidney-lung crosstalk. MATERIALS AND METHODS: The rats were anesthetized, tracheostomized, mechanically ventilated, and randomized to four groups: saline + IRI (n = 12), ANP + IRI (n = 12), ANP + sham (n = 6), and saline + sham (n = 6). Saline (6 mL/kg/h) or ANP (0.2 µg/kg/min) at the rate of 6 mL/kg/h was started 5 min before clamping, respectively. Renal IRI was induced by clamping the left renal pedicle for 30 min. The hemodynamics, arterial blood gases, and plasma concentrations of creatinine and lactate were measured at baseline and 1, 2, and 3 h after declamping. Lung wet-to-dry ratio was measured. The mRNA expression of tumor necrosis factor (TNF)-α, interleukin (IL) 1ß, and IL-6 and histologic localization of TNF-α in the kidney and lung were measured. RESULTS: Renal IRI induced metabolic acidosis, pulmonary edema, increases in plasma concentrations of creatinine and lactate, and augmentation of the cytokine mRNA expression and histologic localization of TNF-α in the kidney and Renal IRI induced lung. ANP prevented IRI-induced metabolic acidosis, pulmonary edema, increases in creatinine, lactate, and the cytokine mRNA expression, attenuated histologic localization of TNF-α in the kidney and lung, and increased oxygenation. CONCLUSIONS: ANP has renoprotective and anti-inflammatory effects on the kidney and lung in a rat model of renal IRI, suggesting that ANP attenuates kidney-lung crosstalk.

Inhibition of poly (adenosine diphosphate-ribose) polymerase attenuates lung-kidney crosstalk induced by intratracheal lipopolysaccharide instillation in rats.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a severe form of lung injury that frequently occurs during pneumonia and sepsis. Lung inflammation in ARDS patients may have deleterious effects on remote organs such as the kidney. The nuclear enzyme poly(adenosine diphosphate-ribose) polymerase (PARP) enhances the nuclear factor (NF)-κB-dependent transcription of inflammatory cytokines. This study was conducted to elucidate two questions: first, whether the activation of PARP and NF-κB mediates the renal inflammation secondary to the lipopolysaccharide (LPS)-induced acute lung inflammation; second, whether a PARP inhibitor, 3-aminobenzamide (3-AB), attenuates lung and kidney inflammation by inhibiting NF-κB-dependent proinflammatory cytokines. METHODS: Male Sprague-Dawley rats were anesthetized, ventilated, and divided into three groups; a control group (n = 8); an LPS group (n = 12) intratracheally instilled with LPS (16 mg/kg), and an LPS + 3-AB group (n = 12) given the same dose of LPS by the same method followed by an intravenous injection of 3-AB (20 mg/kg). Hemodynamics, arterial blood gas, and the plasma levels of lactate, creatinine and potassium were measured at 0,1,2,3, and 4 h after treatment. The lung wet/dry ratio was measured at 4 h. The mRNA expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-6 in the lung and kidney were measured by TaqMan real-time PCR. PARP and NF-κB in the lung and kidney were histologically examined by immunostaining and assigned expression scores. RESULTS: LPS induced metabolic acidosis, hypotension, hypoxemia, increased the lung wet/dry ratio, increased the plasma levels of creatinine and potassium, and increased the cytokine mRNA expressions in the lung and kidney. All of these effects were associated with strong expression of PARP and NF-κB. Treatment with 3-AB prevented the LPS-induced metabolic acidosis and hypotension, reduced the plasma levels of lactate, creatinine and potassium, reduced the cytokine mRNA expressions, reduced the expression of PARP and NF-κB, improved pulmonary edema and oxygenation and preserved renal function. CONCLUSIONS: The PARP inhibition attenuated lung-kidney crosstalk induced by intratracheal LPS instillation, partly via an inhibition of NF-κB dependent proinflammatory cytokines.

Negative pressure pulmonary edema due to upper airway obstruction after general anesthesia in a patient with Parkinson's disease: A case report.

In a patient with Parkinson's disease (PD) who underwent spine surgery 13 h after the last anti-Parkinson medications, negative pressure pulmonary edema from upper airway obstruction developed immediately after extubation. Although oxygenation improved with high-flow nasal cannula therapy, such complications might develop due to abrupt discontinuation of medication for PD.

Incidences of and risk factors for clinical and subclinical contrast-associated acute kidney injury in patients who underwent neuroendovascular surgery.

BACKGROUND: Contrast-associated acute kidney injury (CA-AKI) can develop after intravascular administration of iodinated contrast media. Neutrophil gelatinase-associated lipocalin (NGAL) is an early marker for AKI that helps to detect subclinical CA-AKI. We investigated the incidence of and risk factors for clinical and subclinical CA-AKI in patients who underwent neuroendovascular surgery. METHODS: We retrospectively investigated 228 patients who underwent neuroendovascular surgery in 2020. Changes in serum creatinine and urine output were used to detect clinical CA-AKI. Urine NGAL concentration was used to detect subclinical CA-AKI in 67 out of 228 patients. RESULTS: In 228 patients, serum creatinine, hemoglobin, hematocrit, total protein, and blood urea nitrogen (BUN) decreased significantly (p < 0.001) after surgery. However, serum creatinine decreased less significantly (p < 0.05) than hemoglobin, hematocrit, total protein, and BUN on postoperative Day 3. Two patients out of 228 developed clinical CA-AKI, and seven patients out of 67 with urine NGAL measurements developed subclinical CA-AKI. Multivariate regression analysis revealed that diabetes mellitus and carotid artery stenosis were significantly (p < 0.05) associated with the development of clinical and/or subclinical CA-AKI. CONCLUSION: There was a large difference between the incidences of clinical CA-AKI (0.88%) and subclinical CA-AKI (10.4%). The difference might have primarily resulted from the different sensitivities between serum creatinine and urine NGAL and possibly from underestimation of the incidence of clinical AKI due to a postoperative decrease in serum creatinine caused by hemodilution. In addition to diabetes mellitus, carotid artery stenosis could also be a risk factor for CA-AKI.

Comparison of desflurane and propofol in the speed and the quality of emergence from anesthesia in patients undergoing lung cancer surgery-a prospective, randomized study.

Background: Anesthesia with desflurane or propofol enables rapid emergence. In patients undergoing lung cancer surgery, however, the speed of emergence from desflurane, but not from propofol, may be affected by the deteriorated postoperative respiratory function. We prospectively compared the speed and quality of emergence between desflurane and propofol. Methods: We conducted a parallel study. Eighty patients scheduled for lung cancer surgery were randomly allocated to Desflurane group (Group D) and Propofol group (Group P). Combined general and epidural anesthesia was performed in the identical way except for the anesthetic. Results: There was no significant difference between the groups in the time to awakening, extubation, or orientation. However, emergence agitation (EA) occurred more frequently in Group D than in Group P (20/40 vs. 4/40, P<0.001). Numbers of patients not achieving full scores in respiration and circulation components of the modified Aldrete score 5 min after extubation were more in Group D (4/40 vs. 0/40, P=0.040; and 8/40 vs. 2/40, P=0.043, respectively). More patients required antiemetics during postoperative 24 hours in Group D (15/40 vs. 7/40, P=0.045). Conclusions: Desflurane was not inferior to propofol in the speed of emergence from anesthesia after lung cancer surgery, but it was slightly inferior to propofol in the quality of emergence. Trial Registration: UMIN-CTR identifier: UMIN000009221.

Rhabdomyolysis secondary to hypervirulent Klebsiella pneumoniae infection: A case report.

Hypervirulent Klebsiella pneumoniae (hvKP) is recognized as a lifethreatening community-acquired infection associated with pyogenic liver abscess. However, rhabdomyolysis secondary to hvKP infection is rare. To the best of our knowledge, we report the first case of rhabdomyolysis due to hvKP infection in a patient who survived septic shock syndrome.

Dilutional acidosis during whole lung lavage under general anesthesia due to excessive absorption of normal saline.

BACKGROUND: Whole lung lavage (WLL) is an effective therapy for pulmonary alveolar proteinosis. We report a rare dilutional acidosis following WLL in a female patient. CASE PRESENTATION: Under general anesthesia, a left-sided double-lumen tube was inserted with its bronchial lumen connected to the saline delivery system. Preoperatively, arterial blood gases were within normal limits. During 14 l of fluid was instilled into the lung for 2.5 hours, a decrease in pH, K+, and base excess, alongside an increase in Na+ and Cl-, indicated a strong ion difference; the diagnosis was dilutional hyperchloremic metabolic acidosis. Although she remained hemodynamically stable and had no indicators of massive absorption, she stayed in the ICU for mechanical ventilation for one night out of concern of pulmonary edema. CONCLUSIONS: Inappropriate irrigating fluid pressure might lead to absorption of normal saline. Continuous monitoring and careful observation during WLL can help prevent intraoperative dilutional acidosis.

Cardiovascular and renal effects of carperitide and nesiritide in cardiovascular surgery patients: a systematic review and meta-analysis.

INTRODUCTION: Acute kidney injury (AKI) following cardiovascular surgery is a common disease process and is associated with both morbidity and mortality. The aim of our study was to evaluate the cardiovascular and renal effects of an atrial natriuretic peptide (ANP, carperitide) and a B-type (or brain) natriuretic peptide (BNP, nesiritide) for preventing and treating AKI in cardiovascular surgery patients. METHODS: Electronic databases, including PubMed, EMBASE and references from identified articles were used for a literature search. RESULTS: Data on the infusion of ANP or BNP in cardiovascular surgery patients was collected from fifteen randomized controlled trials and combined. The infusion of ANP or BNP increased the urine output and creatinine clearance or glomerular filtration rate, and reduced the use of diuretics and the serum creatinine levels. A meta-analysis showed that ANP infusion significantly decreased peak serum creatinine levels, incidence of arrhythmia and renal replacement therapy. The meta-analysis also showed that ANP or BNP infusion significantly decreased the length of ICU stay and hospital stay compared with controls. However, the combined data were insufficient to determine how ANP or BNP infusion during the perioperative period influences long-term outcome in cardiovascular surgery patients. CONCLUSIONS: The infusion of ANP or BNP may preserve postoperative renal function in cardiovascular surgery patients. A large, multicenter, prospective, randomized controlled trial will have to be performed to assess the therapeutic potential of ANP or BNP in preventing and treating AKI in the cardiovascular surgical setting.

Effect of Recombinant Human Soluble Thrombomodulin on Coagulation-Related Variables in Patients With Sepsis-Induced Disseminated Intravascular Coagulation: A Retrospective Observational Study.

To evaluate associations among coagulation-related variables, resolution of disseminated intravascular coagulation (DIC) and mortality, we retrospectively investigated 123 patients with sepsis-induced DIC treated with recombinant human soluble thrombomodulin (rTM). Changes in coagulation-related variables before and after treatment with rTM were examined. Further, associations between coagulation-related variables and DIC resolution were evaluated. The platelet count, prothrombin international normalized ratio (PT-INR), and fibrin/fibrinogen degradation products (FDP) significantly (p < .001) improved after rTM administration in survivors (n = 98), but not in nonsurvivors (n = 25). However, the DIC score significantly (p < .001) reduced in survivors and in nonsurvivors. Among coagulation-related variables examined before rTM, only PT-INR was significantly (p = .0395) lower in survivors than in nonsurvivors, and PT-INR before rTM was significantly (p = .0029) lower in patients attaining than not attaining DIC resolution (n = 87 and 36, respectively). The 28-day mortality was significantly lower in patients attaining than not attaining DIC resolution (11.5% vs 41.7%, p = .0001). In conclusion, the initiation of rTM administration before marked PT-INR elevation may be important to induce DIC resolution and thus to decrease mortality in patients with sepsis-induced DIC. Conversely, the treatment with rTM in patients with marked PT-INR elevation may be not so effective in achieving such goals.

Up-to-date information on polymyxin B-immobilized fiber column direct hemoperfusion for septic shock.

Endotoxin adsorption therapy by polymyxin B-immobilized fiber column direct hemoperfusion (PMX-DHP) has been used for the treatment of septic shock patients. Endotoxin, an outer membrane component of Gram-negative bacteria, plays an important role in the pathogenesis of septic shock. Endotoxin triggers a signaling cascade for leukocytes, macrophage, and endothelial cells to secrete various mediators including cytokines and nitric oxide, leading to septic shock and multiple organ dysfunction syndrome. PMX-DHP directly adsorbed not only endotoxin but also monocytes and anandamide. It reduced blood levels of inflammatory cytokines such as interleukin (IL)-1, IL-6, tumor necrosis factor-alpha and IL-17A, adhesion molecules, plasminogen activator inhibitor 1, and high mobility group box-1. As a result, PMX-DHP increased blood pressure and reduced the dose of vasoactive-inotropic agents. PMX-DHP improved monocyte human leukocyte antigen-DR expression in patients with severe sepsis and septic shock. A post hoc analysis of EUPHRATES (Evaluating the Use of Polymyxin B Hemoperfusion in Randomized Controlled Trial of Adults Treated for Endotoxemia and Septic Shock) trial has shown that PMX-DHP significantly reduced 28-day mortality compared with the control group in septic shock patients with endotoxin activity assay level between 0.60 and 0.89. Longer duration of PMX-DHP may be another strategy to bring out the beneficial effects of PMX-DHP. Further studies are needed to confirm the efficacy of PMX-DHP treatment for septic shock.

Correlation between urinary biomarker and organ failure in patients with sepsis and patients after esophagectomy: a prospective observational study.

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) is a diagnostic marker for acute kidney injury (AKI). NGAL expression is highly induced not only in kidney injury but also in bacterial infection, inflammation, and cancer. The factors regulating NGAL expression are proinflammatory cytokines, and plasma NGAL levels have been increased in septic shock. However, there are no reports of urine neutrophil gelatinase-associated lipocalin (uNGAL) levels after open esophagectomy. METHODS: We prospectively enrolled critically ill patients, including patients with sepsis (n = 45) and patients who underwent open esophagectomy (n = 40). We compared vital signs, PaO2/FIO2, serum C-reactive protein (CRP) levels, acute physiology and chronic health evaluation (APACHE) II score, sequential organ failure assessment (SOFA) score, and uNGAL levels between the sepsis group and the esophagectomy group. Then, we investigated whether uNGAL is associated with the severity of illness and organ failure, and whether uNGAL is a reliable screening test for AKI. RESULTS: The median uNGAL levels, APACHE II score, SOFA score, and serum CRP levels were significantly (p < 0.001) higher in the sepsis group than in the esophagectomy group on ICU day 1. In the sepsis group, uNGAL levels were significantly (p < 0.05) correlated with APACHE II score and SOFA score on intensive care unit (ICU) day 1, 2, and 3. In the esophagectomy group, uNGAL levels were significantly (p < 0.05) correlated with SOFA score on ICU day 3 and 4. In the sepsis group, 1 patient developed AKI stage 2 and 6 patients developed AKI stage 3. No patients developed AKI in the esophagectomy group. In a total of 85 patients of this study, 80 patients had an abnormal value of uNGAL and only 7 patients (8.7%) of those 80 patients developed AKI. CONCLUSIONS: uNGAL levels were correlated with the severity of illness and organ failure in critically ill patients. The value of uNGAL increases under the surgical and inflammatory responses, thereby losing a significance of a screening test of AKI in critically ill patients.

Specific airway management for SVC replacement during giant anterior mediastinal tumor resection.

BACKGROUND: Giant anterior mediastinal tumor (GAMT) resection is a challenging procedure, for which anesthesiologist might take to need special precautions. CASE PRESENTATION: A 48-year-old male patient had been scheduled to undergo GAMT resection and superior vena cava (SVC) replacement. The tumor spread surrounding SVC and left main bronchus (LMB), resulting in small volume of his left lung. A soft left-sided double lumen tube (DLT) was selected to keep the patency of LMB during left one lung ventilation (OLV) against the tumor weight. Semi-awake intubation with spontaneous breathing was selected for DLT insertion to avoid lower airway occlusion. During left OLV after right open thoracotomy, his SPO2 decreased below to 90%. We performed selective right upper lobe bronchial blockade using the combination of DLT and bronchial blocker. The surgery was successfully completed with this strategy. CONCLUSIONS: Although such cases are rare, they are informative for anesthesiologists, providing optional strategies.

Effects of human atrial natriuretic peptide on renal function in patients undergoing abdominal aortic aneurysm repair.

OBJECTIVE: Ischemia-reperfusion injury is an important cause of renal dysfunction after abdominal aortic aneurysm repair. Human atrial natriuretic peptide (hANP) is a potent endogenous natriuretic, diuretic, and vasorelaxant peptide. The objective of the present study was to evaluate the effects of hANP on renal function in patients undergoing abdominal aortic aneurysm repair. DESIGN: A prospective, randomized, placebo-controlled study SETTING: Intensive care unit of a university hospital. PATIENTS: Forty patients undergoing elective abdominal aortic aneurysm repair. INTERVENTIONS: The patients were randomized to receive a continuous infusion of either hANP (0.01-0.05 microg/kg/min) (n = 20) or placebo (n = 20) immediately before aortic cross-clamping. The infusion of hANP or placebo continued for 48 hrs. MEASUREMENTS AND MAIN RESULTS: Blood and urine samples were taken before surgery, at admission to the intensive care unit, and on days 1, 2, and 3 postoperatively, for measurement of serum concentrations of sodium, creatinine, and blood urea nitrogen and plasma concentrations of ANP and brain natriuretic peptide (BNP). Urine volume and urinary concentrations of N-acetyl-beta-D-glucosaminidase (NAG), sodium, and creatinine were also measured. The mean plasma concentration of ANP was significantly higher in the hANP group than in the placebo group. The mean plasma BNP concentration was significantly lower in the hANP group than in the placebo group. The mean serum concentrations of creatinine and blood urea nitrogen were significantly (p < .05) lower in the hANP group than in the placebo group. The mean urine volume and mean creatinine clearance were significantly (p < .05) higher in the hANP group than in the placebo group. The mean urinary NAG/creatinine ratio was significantly (p < .05) lower in the hANP group than in the placebo group. CONCLUSIONS: The intraoperative and postoperative infusion of low-dose hANP preserved renal function in patients undergoing abdominal aortic aneurysm repair. Further studies are needed to assess the efficacy of prophylactic hANP infusion on perioperative renal outcome.

High-flow oxygen via tracheostomy facilitates weaning from prolonged mechanical ventilation in patients with restrictive pulmonary dysfunction: two case reports.

BACKGROUND: Weaning from prolonged mechanical ventilation is extremely difficult in tracheostomized patients with restrictive pulmonary dysfunction. High-flow oxygen via tracheostomy supplies heated and humidified oxygen gas at > 10 L/minute. However, little has been reported on the use of high-flow oxygen via tracheostomy during weaning from ventilators in patients with restrictive pulmonary dysfunction. We report successful weaning from ventilators in patients with restrictive pulmonary dysfunction using high-flow oxygen via tracheostomy. CASE PRESENTATION: The first patient is a 78-year-old Japanese man with severe pneumococcal pneumonia who was mechanically ventilated for more than 1 month after esophagectomy for esophageal cancer. After he underwent tracheostomy because of prolonged mechanical ventilation, restrictive pulmonary dysfunction appeared: tidal volume 230-240 mL and static compliance 14-15 mL/cmH2O with 10 cmH2O pressure support ventilation. He was weaned from the ventilator under inspiratory support with high-flow oxygen via tracheostomy over a period of 16 days (flow at 40 L/minute and fraction of inspired oxygen of 0.25). The second patient is a 69-year-old Japanese man who developed aspiration pneumonia after esophagectomy and received prolonged mechanical ventilation via tracheostomy. He developed restrictive pulmonary dysfunction. High-flow oxygen via tracheostomy (flow at 40 L/minute with fraction of inspired oxygen of 0.25) was administered with measurement of the airway pressure and at the entrance of the tracheostomy tube. The measured values were as follows: 0.21-0.3 cmH2O, 0.21-0.56 cmH2O, 0.54-0.91 cmH2O, 0.76-2.01 cmH2O, 1.17-2.01 cmH2O, and 1.76-2.01 cmH2O at 10 L/minute, 20 L/minute, 30 L/minute, 40 L/minute, 50 L/minute, and 60 L/minute, respectively. The airway pressures were continuously positive and did not become negative even during inspiration, suggesting that high-flow oxygen via tracheostomy reduces inspiratory effort. He was weaned from the ventilator under inspiratory support with high-flow oxygen via tracheostomy over a period of 12 days. CONCLUSIONS: High-flow oxygen via tracheostomy may reduce the inspiratory effort and enhance tidal volume by delivering high-flow oxygen and facilitate weaning from prolonged mechanical ventilation in patients with restrictive pulmonary dysfunction.

Nonischemic lung injury by mediators from unilateral ischemic reperfused lung: ameliorating effect of tumor necrosis factor-alpha-converting enzyme inhibitor.

We hypothesized that the ischemic reperfused (I/R) lung expresses and liberates tumor necrosis factor-alpha (TNF-alpha) to injure the nonischemic lung, and that a TNF-alpha-converting enzyme inhibitor (TACEI) prevents injury of the nonischemic lung by blocking TNF-alpha liberation from the I/R lung. In isolated ventilated rat lungs in which differential perfusion to the right (RL) or left (LL) lung was feasible, LLs were selectively made ischemic (60 min) while maintaining perfusion to RLs, then reperfused (30 min) in a nonrecirculating manner with buffer solution (non-R; n = 18) or in a recirculating manner with buffer containing TACEI (TACEI[+]; n = 18) or without TACEI (TACEI[-]; n = 18). Ischemia reperfusion induced TNF-alpha messenger RNA expression in the ischemic LLs; the expression was highest in TACEI(+) group (P < 0.01). The expression of TNF-alpha, which was detected as immunofluorescence signals on CD34-positive endothelial cells, was observed in ischemic LLs; the highest expression being that in the TACEI(+) group. Wet/dry ratio and protein content in bronchoalveolar lavage fluid were higher in LLs than in RLs, and among the RLs, these 2 parameters were significantly increased in the TACEI(-) group (P < 0.01) in which the RLs were exposed to the TNF-alpha-rich perfusate. On the other hand, protein content in bronchoalveolar lavage fluid of the TACEI(+) group in which RLs were exposed to recirculating perfusate containing little TNF-alpha was decreased to a level close to but still higher than that in the non-R group (P < 0.05). The unilateral I/R lung affected the permeability of the nonischemic lung by liberating mainly TNF-alpha and induced TNF-alpha, interleukin (IL)-1beta, IL-6, and IL-10 messenger RNA expression in the nonischemic lung. These findings support the idea of organ-organ interaction in which an injured organ affects a remote organ by liberating humoral mediators.