Preventive Hyperbaric Oxygen Therapy for Asymptomatic Left Ventricular Air During CT-Guided Lung Needle Biopsy.

Lung needle biopsy can cause air to enter the vessels due to the traffic between the vessels and the trachea. Hyperbaric oxygen therapy (HBOT) according to the U.S. Navy Treatment Table (USNTT) 6 or 6A protocol is used for arterial gas embolism (AGE). However, no treatment or HBOT protocol for asymptomatic intra-arterial air has been established. Here we report two cases of asymptomatic intra-arterial air during lung needle biopsy that were preventively treated with HBOT according to the USNTT 5 protocol. In case 1, a 72-year-old man with malignant lymphoma in remission underwent computed tomography (CT)-guided lung needle biopsy of a nodule in his right lung. During the biopsy, the patient developed a cough, followed by chest pain and dyspnea. Chest CT revealed a right pneumothorax and air in the left ventricle and aorta. The patient did not present with symptoms suggestive of AGE. After thoracic drainage, 4.5 hours after onset, the patient underwent HBOT according to the USNTT 5 protocol. After one session in the hyperbaric chamber, follow-up whole-body CT showed disappearance of intravascular air. In case 2, a 69-year-old man with chronic obstructive pulmonary disease underwent CT-guided lung needle biopsy of a nodule in his right lung. Post-examination CT showed intravascular air in the aorta, pulmonary artery and vein, and left ventricle. However, the patient had no symptoms. One hour after onset, the patient underwent HBOT according to the USNTT 5 protocol. A whole-body CT the next day confirmed the disappearance of intravascular air. Both patients were discharged without sequelae. HBOT is an effective treatment to flush out intra-arterial air and inhibit the expression of adhesion molecules. Asymptomatic intra-arterial air may be adequately treated with HBOT according to a short protocol such as USNTT 5.

Chest CT findings in severe acute respiratory distress syndrome requiring V-V ECMO: J-CARVE registry.

BACKGROUND: Chest computed tomography findings are helpful for understanding the pathophysiology of severe acute respiratory distress syndrome (ARDS). However, there is no large, multicenter, chest computed tomography registry for patients requiring veno-venous extracorporeal membrane oxygenation (V-V ECMO). The aim of this study was to describe chest computed tomography findings at V-V ECMO initiation and to evaluate the association between the findings and outcomes in severe ARDS. METHODS: This multicenter, retrospective cohort study enrolled patients with severe ARDS on V-V ECMO, who were admitted to the intensive care units of 24 hospitals in Japan between January 1, 2012, and December 31, 2022. RESULTS: The primary outcome was 90-day in-hospital mortality. The secondary outcomes were the successful liberation from V-V ECMO and the values of static lung compliance. Among the 697 registry patients, of the 582 patients who underwent chest computed tomography at V-V ECMO initiation, 394 survived and 188 died. Multivariate Cox regression showed that traction bronchiectasis and subcutaneous emphysema increased the risk of 90-day in-hospital mortality (hazard ratio [95% confidence interval] 1.77 [1.19-2.63], p = 0.005 and 1.97 [1.02-3.79], p = 0.044, respectively). The presence of traction bronchiectasis was also associated with decreased successful liberation from V-V ECMO (odds ratio: 0.27 [0.14-0.52], p < 0.001). Lower static lung compliance was associated with some chest computed tomography findings related to changes outside of pulmonary opacity, but not with the findings related to pulmonary opacity. CONCLUSIONS: Traction bronchiectasis and subcutaneous emphysema increased the risk of 90-day in-hospital mortality in patients with severe ARDS who required V-V ECMO.

Impact of the failure of initial insertion of a peripheral intravascular catheter on the development of adverse events in patients admitted to the intensive care unit from the emergency room: A post hoc analysis of the AMOR-VENUS study.

Aim: To investigate an association between failure of initial peripheral intravascular catheter (PIVC) insertion and adverse events in patients admitted to the intensive care unit (ICU) from the emergency room (ER). Methods: This study was a post hoc analysis of the AMOR-VENUS study, a multicenter cohort study that included 22 institutions and 23 ICUs in Japan between January and March of 2018. Study participants included consecutive adult patients admitted to the ICU with PIVCs inserted in ICU during the study period exclusively from the ER. The primary outcome was adverse events. Adverse events were composite of arterial puncture, hematoma, extravasation, nerve injury, tendon injury, compartment syndrome, pain, redness, bad location, and effusion. Multivariate logistic regression analyses were performed to assess the association between adverse events and the failure of initial PIVC insertion. Results: In total, 363 patients and 1121 PIVCs were analyzed. Moreover, 199 catheters failed to insert properly, and 36 patients and 107 catheters experienced adverse events. After performing multivariate logistic regression analysis, there were statistically significant associations in the odds ratio (OR) and 95% confidence interval (CI) for the failure of initial insertion (OR, 1.66 [1.02-2.71]; p = 0.04). Conclusion: Failure of initial insertion may be a risk factor for adverse events. We could potentially provide various interventions to avoid failure of initial PIVC insertion. For example, PIVC insertion could be performed by experienced practitioners.

Fatal case of Capnocytophaga sepsis from a dog bite in a patient with splenic hypoplasia.

Background: Capnocytophaga canimorsus is an oral commensal bacteria in dogs and may cause severe infection following a dog bite. This is a case of fatal C. canimorsus sepsis with acute infectious purpura fulminans (AIPF) in a healthy patient with splenic hypoplasia. Case Presentation: A healthy 49-year-old man was admitted to the intensive care unit (ICU) for septic shock and AIPF 4 days after a dog bite to his mouth. Computed tomography revealed a small spleen measuring 53 cm3 but no other source of infection. Despite intensive care, the patient died of multiple organ failure and progressive shock on the fifth ICU day. Polymerase chain reaction of blood samples identified the C. canimorsus gene on a later day. Conclusion: Capnocytophaga canimorsus from dog bites may cause fatal AIPF. Splenic hypoplasia and bite wounds in well-perfused areas such as the oral cavity are possible risk factors for sepsis. All dog bites should warrant medical attention.

A study of the risk factors for phlebitis in patients stratified using the acute physiology and chronic health evaluation II score and admitted to the intensive care unit: A post hoc analysis of the AMOR-VENUS study.

Introduction: Peripheral intravascular catheters (PIVCs) are inserted in most patients admitted to the intensive care unit (ICU). Previous research has discussed various risk factors for phlebitis, which is one of the complications of PIVCs. However, previous studies have not investigated the risk factors based on the patient's severity of illness, such as the Acute Physiology and Chronic Health Evaluation (APACHE) II score. Different treatments can be used based on the relationship of risk factors to the illness severity to avoid phlebitis. Therefore, in this study, we investigate whether the risk factors for phlebitis vary depending on the APACHE II score. Materials and methods: This study was a post hoc analysis of the AMOR-VENUS study involving 23 ICUs in Japan. We included patients with age ≥ 18 years and consecutive admissions to the ICU with PIVCs inserted during ICU admission. The primary outcome was phlebitis, and the objective was the identification of the risk factors evaluated by hazard ratio (HR) and 95% confidence interval (CI). The cut-off value of the APACHE II score was set as ≤15 (group 1), 16-25 (group 2), and ≥26 (group 3). Multivariable marginal Cox regression analysis was performed for each group using the presumed risk factors. Results: A total of 1,251 patients and 3,267 PIVCs were analyzed. Multivariable marginal Cox regression analysis reveals that there were statistically significant differences among the following variables evaluated HR (95%CI): (i) in group 1, standardized drug administration measures (HR, 0.4 [0.17-0.9]; p = 0.03) and nicardipine administration (HR, 2.25 [1.35-3.75]; p < 0.01); (ii) in group 2, insertion in the upper arm using the forearm as a reference (HR, 0.41 [0.2-0.83]; p = 0.01), specified polyurethane catheter using polyurethane as a reference (HR, 0.56 [0.34-0.92]; p = 0.02), nicardipine (HR, 1.9 [1.16-3.12]; p = 0.01), and noradrenaline administration (HR, 3.0 [1.52-5.88]; p < 0.01); (iii) in group 3, noradrenaline administration (HR, 3.39 [1.14-10.1]; p = 0.03). Conclusion: We found that phlebitis risk factors varied according to illness severity. By considering these different risk factors, different treatments may be provided to avoid phlebitis based on the patient's severity of illness.

Risk factors for peripheral venous catheter-related phlebitis stratified by body mass index in critically ill patients: A post-hoc analysis of the AMOR-VENUS study.

Introduction: Phlebitis is an important complication in patients with peripheral intravascular catheters (PIVCs). Although an association between body mass index (BMI) and phlebitis has been suggested, the risk of phlebitis according to BMI has not been well elucidated. Therefore, in this study, we analyzed the risk of phlebitis according to BMI in patients in the intensive care unit (ICU). Materials and methods: This study undertook a secondary analysis of the data from a prospective multicenter observational study assessing the epidemiology of phlebitis at 23 ICUs in Japan. Patients admitted into the ICU aged ≥18 years with a new PIVC inserted after ICU admission were consecutively enrolled and stratified into the following groups based on BMI: Underweight (BMI < 18.5 kg/m2), normal weight (18.5 ≤ BMI < 25.0 kg/m2), and overweight/obese (BMI ≥ 25.0 kg/m2). The primary outcome was phlebitis. The risk factors for phlebitis in each BMI-based group were investigated using a marginal Cox regression model. In addition, hazard ratios and 95% confidence intervals were calculated. Results: A total of 1,357 patients and 3,425 PIVCs were included in the analysis. The mean BMI for all included patients was 22.8 (standard deviation 4.3) kg/m2. Among the eligible PIVCs, 455; 2,041; and 929 were categorized as underweight, normal weight, and overweight/obese, respectively. In the underweight group, catheter size ≥ 18 G and amiodarone administration were independently associated with the incidence of phlebitis. Drug administration standardization was associated with the reduction of phlebitis. In the normal weight group, elective surgery as a reason for ICU admission, and nicardipine, noradrenaline, and levetiracetam administration were independently associated with the incidence of phlebitis. Heparin administration was associated with the reduction of phlebitis. In the overweight/obese group, the Charlson comorbidity index, catheter size ≥ 18 G, and levetiracetam administration were independently associated with the incidence of phlebitis. Catheters made from PEU-Vialon (polyetherurethane without leachable additives) and tetrafluoroethylene were associated with the reduction of phlebitis. Conclusion: We investigated the risk factors for peripheral phlebitis according to BMI in ICU and observed different risk factors in groups stratified by BMI. For example, in underweight or overweight patients, large size PIVCs could be avoided. Focusing on the various risk factors for phlebitis according to patients' BMIs may aid the prevention of phlebitis.

Fluid restriction management in the treatment of COVID-19: a single-center observational study.

The relationship between fluid management and the severity of illness, duration of treatment, and outcome of coronavirus disease 2019 (COVID-19) is not fully understood. This study aimed to evaluate whether weight change during hospitalization was associated with COVID-19 severity, length of hospital stay, and route of admission. In this study, we assessed the effectiveness of fluid restriction management in patients with severe COVID-19. COVID-19 patients admitted to our hospital between July 2020 and October 2021 were analyzed. Patients were treated with standard drug therapy based on the Japanese guidelines and respiratory support according to the severity of the disease. Early enteral nutrition, defecation management, and anticoagulation therapy were also administered. Fluid restriction management was performed using furosemide and continuous renal replacement therapy as needed unless hemodynamic instability or hyperlactatemia was present. Patient background, route of admission (ambulance, A; transfer, T), weight at admission and discharge, the severity of illness (oxygen therapy, G1; mechanical ventilation, G2; extracorporeal membrane oxygenation, G3), in-hospital mortality, and length of hospital stay were analyzed. There were 116 subjects: G1 (n = 48), G2 (n = 43), and G3 (n = 25), with ages (median [IQR]) of 58 (47-70), 65 (53-71.5), 56 (51-62) years, 40 (83.3%), 31 (72.1%), and 19 (76.0%) males, respectively. Hospital stays were 4.5 (2-7), 10 (7-16), and 18 (15-26) days, and the in-hospital mortality rates were 0 (0%), 7 (16.3%), and 8 (32%), respectively. Body mass index on admission was 26 (23.1-30.2), 27.1 (22.7-31.1), and 31.5 (27.1-33.1) kg/m2, and weight loss during admission was 1.1 (0-2.9), 4.6 (2.3-5.7), 9.2 (5.6-10.5) kg (P < 0.001, Jonckheere-Terpstra test. Weight loss in the severe group (G2 + G3) was 3.4 (0.5-5.8) kg [A, n = 12] and 5.6 (4.4-9) kg [T, n = 43] [P = 0.026, Mann-Whitney U test]. The lengths of hospital stay were 5 (2-7), 9 (7-15), and 18 (12-26) days [P < 0.001, Jonckheere-Terpstra test]. In our fluid restriction management, patients with severe COVID-19 had significant longer hospital length of stay, weight loss, especially those who were transferred to the hospital.

A burden of fluid, sodium, and chloride due to intravenous fluid therapy in patients with respiratory support: a post-hoc analysis of a multicenter cohort study.

BACKGROUND: Fluid creep, including fluids administered as drug diluents and for the maintenance of catheter patency, is the major source of fluid intake in critically ill patients. Although hypoxemia may lead to fluid restriction, the epidemiology of fluid creep in patients with hypoxemia is unclear. This study aimed to address the burden due to fluid creep among patients with respiratory support according to oxygenation status. METHODS: We conducted a post-hoc analysis of a prospective multicenter cohort study conducted in 23 intensive care units (ICUs) in Japan from January to March 2018. Consecutive adult patients who underwent invasive or noninvasive ventilation upon ICU admission and stayed in the ICU for more than 24 h were included. We excluded the following patients when no fluids were administered within 24 h of ICU admission and no records of the ratio of arterial oxygen partial pressure to fractional inspired oxygen. We investigated fluid therapy until 7 days after ICU admission according to oxygenation status. Fluid creep was defined as the fluids administered as drug diluents and for the maintenance of catheter patency when administered at ≤ 20 mL/h. RESULTS: Among the 588 included patients, the median fluid creep within 24 h of ICU admission was 661 mL (25.2% of the total intravenous-fluid volume), and the proportion of fluid creep gradually increased throughout the ICU stay. Fluid creep tended to decrease throughout ICU days in patients without hypoxemia and in those with mild hypoxemia (p < 0.001 in both patients), but no significant trend was observed in those with severe hypoxemia (p = 0.159). Similar trends have been observed in the proportions of sodium and chloride caused by fluid creep. CONCLUSIONS: Fluid creep was the major source of fluid intake among patients with respiratory support, and the burden due to fluid creep was prolonged in those with severe hypoxemia. However, these findings may not be conclusive as this was an observational study. Interventional studies are, therefore, warranted to assess the feasibility of fluid creep restriction. Trial registration UMIN-CTR, the Japanese clinical trial registry (registration number: UMIN 000028019, July 1, 2017).

Resuscitation from Cardiac Arrest with Tension Gastrothorax Due to Acquired Diaphragmatic Hernia.

Tension gastrothorax is a rare cause of obstructive shock induced by a distended stomach herniating into the thorax through a diaphragmatic defect. We report the process of diagnosis and emergency treatment for tension gastrothorax during cardiopulmonary resuscitation (CPR). A 71-year-old woman with multiple surgical histories had nausea and vomiting for two days. She was transferred to our hospital with circulatory failure and loss of consciousness. She presented pulseless electric activity and received CPR immediately after arrival. The right atrium and right ventricle were collapsed in the echocardiography. A chest X-ray demonstrated a dilated intestine extending from the peritoneal cavity to the mediastinum. The nasogastric tube (NGT) drained 1000 mL of stomach content and alleviated the abdominal distension, and spontaneous circulation returned immediately after the drainage. Thoracoabdominal CT showed the stomach and the transverse colon had escaped from the peritoneal cavity to the mediastinum. We diagnosed the situation as tension gastrothorax due to an acquired diaphragmatic hernia. History of multiple surgery and multiple operative scars was the first step of the diagnostic process, and the chest X-ray during CPR was the key to the diagnosis. Tension gastrothorax can be misdiagnosed as other conditions. A chest X-ray should be preceded in non-trauma settings, unlike the setting of a tension pneumothorax in trauma patients. Gastrointestinal decompression with NGT placement could be attempted quickly to improve the hemodynamic condition.

Risk factors for peripheral intravascular catheter-related phlebitis in critically ill patients: analysis of 3429 catheters from 23 Japanese intensive care units.

BACKGROUND: Phlebitis is an important complication occurring in patients with peripheral intravascular catheters (PIVCs). The risk factors for phlebitis in the intensive care unit (ICU) was examined. METHODS: A secondary analysis of a prospective multicenter cohort study was conducted, involving 23 ICUs in Japan-the AMOR-VENUS study. Consecutive patients aged ≥ 18 years admitted to the ICU with newly inserted PIVCs after ICU admission were enrolled. Characteristics of the ICU, patients, PIVCs, and the drugs administered via PIVCs were recorded. A marginal Cox regression model was used to identify the risk factors associated with phlebitis. RESULTS: A total of 2741 consecutive patients from 23 ICUs were reviewed for eligibility, resulting in 1359 patients and 3429 PIVCs being included in the analysis population. The median dwell time was 46.2 h (95% confidence interval [CI], 21.3-82.9). Phlebitis occurred in 9.1% (95% CI, 8.2-10.1%) of catheters (3.5 cases/100 catheter days). The multivariate analysis revealed that the only factors that increased the risk of developing phlebitis were drugs administered intravenously. This study included 26 drugs, and 4 were associated with increased phlebitis: nicardipine (HR, 1.85; 95% CI, 1.29-2.66), noradrenaline (HR, 2.42; 95% CI, 1.40-4.20), amiodarone (HR, 3.67; 95% CI, 1.75-7.71) and levetiracetam (HR, 5.65; 95% CI, 2.80-11.4). Alternatively, factors significantly associated with a reduced risk of phlebitis were: standardized drug administration measures in the ICU (HR, 0.35; 95% CI, 0.17-0.76), 30≤ BMI (HR, 0.43; 95% CI, 0.20-0.95), catheter inserted by a doctor as nurse reference (HR, 0.55; 95% CI, 0.32-0.94), and upper arm insertion site as forearm reference (HR, 0.52; 95% CI, 0.32-0.85). The nitroglycerin was associated with a reduced phlebitis risk (HR, 0.22; 95% CI, 0.05-0.92). CONCLUSION: Various factors are involved in the development of phlebitis caused by PIVCs in critically ill patients, including institutional, patient, catheter, and drug-induced factors, indicating the need for appropriate device selection or models of care in the ICU. TRIAL REGISTRATION: UMIN-CTR, the Japanese clinical trial registry (registration number: UMIN000028019, July 1, 2017).

Successful application of angioembolization and thoracic endovascular aortic repair (TEVAR) in a retrograde type-A acute aortic dissection with polytrauma.

A 53-year-old man underwent thoracic endovascular aortic repair for persistent false lumen perfusion and limb salvage because of type A aortic dissection, severe lower-limb ischemia, and bleeding (mediastinal hematoma, bilateral lung contusion, liver injury, and splenic injury) caused by blunt trauma. We embolized the left supreme intercostal artery to control active mediastinal hemorrhage. Acute hemorrhage and leg ischemia were well controlled; however, residual blood flow in the false lumen persisted. We performed a Zone 2 thoracic endovascular aortic repair and discharged the patient on day 67. Thoracic endovascular aortic repair is a practical option for treating traumatic type A dissection.

Monitoring of gastric residual volume during enteral nutrition.

BACKGROUND: The main goal of enteral nutrition (EN) is to manage malnutrition in order to improve clinical outcomes. However, EN may increase the risks of vomiting or aspiration pneumonia during gastrointestinal dysfunction. Consequently, monitoring of gastric residual volume (GRV), that is, to measure GRV periodically and modulate the speed of enteral feeding according to GRV, has been recommended as a management goal in many intensive care units. Yet, there is a lack of robust evidence that GRV monitoring reduces the level of complications during EN. The best protocol of GRV monitoring is currently unknown, and thus the precise efficacy and safety profiles of GRV monitoring remain to be ascertained. OBJECTIVES: To investigate the efficacy and safety of GRV monitoring during EN. SEARCH METHODS: We searched electronic databases including CENTRAL, MEDLINE, Embase, and CINAHL for relevant studies on 3 May 2021. We also checked reference lists of included studies for additional information and contacted experts in the field. SELECTION CRITERIA: We included randomized controlled trials (RCTs), randomized cross-over trials, and cluster-RCTs investigating the effects of GRV monitoring during EN. We imposed no restrictions on the language of publication. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the search results for eligible studies and extracted trial-level information from each included study, including methodology and design, characteristics of study participants, interventions, and outcome measures. We assessed risk of bias for each study using Cochrane's risk of bias tool. We followed guidance from the GRADE framework to assess the overall certainty of evidence across outcomes. We used a random-effects analytical model to perform quantitative synthesis of the evidence. We calculated risk ratios (RRs) with 95% confidence intervals (CIs) for dichotomous and mean difference (MD) with 95% CIs for continuous outcomes. MAIN RESULTS: We included eight studies involving 1585 participants. All studies were RCTs conducted in ICU settings. Two studies (417 participants) compared less-frequent (less than eight hours) monitoring of GRV against a regimen of more-frequent (eight hours or greater) monitoring. The evidence is very uncertain about the effect of frequent monitoring of GRV on mortality rate (RR 0.91, 95% CI 0.60 to 1.37; I² = 8%; very low-certainty evidence), incidence of pneumonia (RR 1.08, 95% CI 0.64 to 1.83; heterogeneity not applicable; very low-certainty evidence), length of hospital stay (MD 2.00 days, 95% CI -2.15 to 6.15; heterogeneity not applicable; very low-certainty evidence), and incidence of vomiting (RR 0.14, 95% CI 0.02 to 1.09; heterogeneity not applicable; very low-certainty evidence). Two studies (500 participants) compared no GRV monitoring with frequent (12 hours or less) monitoring. Similarly, the evidence is very uncertain about the effect of no monitoring of GRV on mortality rate (RR 0.87, 95% CI 0.62 to 1.23; I² = 51%; very low-certainty evidence), incidence of pneumonia (RR 0.70, 95% CI 0.43 to 1.13; heterogeneity not applicable; very low-certainty evidence), length of hospital stay (MD -1.53 days, 95% CI -4.47 to 1.40; I² = 0%; very low-certainty evidence), and incidence of vomiting (RR 1.47, 95% CI 1.13 to 1.93; I² = 0%; very low-certainty evidence). One study (322 participants) assessed the impact of GRV threshold (500 mL per six hours) on clinical outcomes. The evidence is very uncertain about the effect of the threshold for GRV at time of aspiration on mortality rate (RR 1.01, 95% CI 0.74 to 1.38; heterogeneity not applicable; very low-certainty evidence), incidence of pneumonia (RR 1.03, 95% CI 0.72 to 1.46; heterogeneity not applicable; very low-certainty evidence), and length of hospital stay (MD -0.90 days, 95% CI -2.60 to 4.40; heterogeneity not applicable; very low-certainty evidence). Two studies (140 participants) explored the effects of returning or discarding the aspirated/drained GRV. The evidence is uncertain about the effect of discarding or returning the aspirated/drained GRV on the incidence of vomiting (RR 1.00, 95% CI 0.06 to 15.63; heterogeneity not applicable; very low-certainty evidence) and volume aspirated from the stomach (MD -7.30 mL, 95% CI -26.67 to 12.06, I² = 0%; very low-certainty evidence) We found no studies comparing the effects of protocol-based EN strategies that included GRV-related criteria against strategies that did not include such criteria. AUTHORS' CONCLUSIONS: The evidence is very uncertain about the effect of GRV on clinical outcomes including mortality, pneumonia, vomiting, and length of hospital stay.

Occurrence and incidence rate of peripheral intravascular catheter-related phlebitis and complications in critically ill patients: a prospective cohort study (AMOR-VENUS study).

BACKGROUND: The lack of precise information on the epidemiology of peripheral intravascular catheter (PIVC)-related phlebitis and complications in critically ill patients results in the absence of appropriate preventive measures. Therefore, we aimed to describe the epidemiology of the use of PIVCs and the incidence/occurrence of phlebitis and complications in the intensive care unit (ICU). METHODS: This prospective multicenter cohort study was conducted in 23 ICUs in Japan. All consecutive patients aged ≥ 18 years admitted to the ICU were enrolled. PIVCs inserted prior to ICU admission and those newly inserted after ICU admission were included in the analysis. Characteristics of the ICU, patients, and PIVCs were recorded. The primary and secondary outcomes were the occurrence and incidence rate of PIVC-related phlebitis and complications (catheter-related blood stream infection [CRBSI] and catheter failure) during the ICU stay. RESULTS: We included 2741 patients and 7118 PIVCs, of which 48.2% were inserted in the ICU. PIVC-related phlebitis occurred in 7.5% (95% confidence interval [CI] 6.9-8.2%) of catheters (3.3 cases / 100 catheter-days) and 12.9% (95% CI 11.7-14.2%) of patients (6.3 cases / 100 catheter-days). Most PIVCs were removed immediately after diagnosis of phlebitis (71.9%). Grade 1 was the most common phlebitis (72.6%), while grade 4 was the least common (1.5%). The incidence rate of CRBSI was 0.8% (95% CI 0.4-1.2%). In cases of catheter failure, the proportion and incidence rate per 100 intravenous catheter-days of catheter failure were 21% (95% CI 20.0-21.9%) and 9.1 (95% CI 8.7-10.0), respectively. CONCLUSION: PIVC-related phlebitis and complications were common in critically ill patients. The results suggest the importance of preventing PIVC-related complications, even in critically ill patients. TRIAL REGISTRATION: UMIN-CTR, the Japanese clinical trial registry (registration number: UMIN000028019 , July 1, 2017).

Identification of the phytosphingosine metabolic pathway leading to odd-numbered fatty acids.

The long-chain base phytosphingosine is a component of sphingolipids and exists in yeast, plants and some mammalian tissues. Phytosphingosine is unique in that it possesses an additional hydroxyl group compared with other long-chain bases. However, its metabolism is unknown. Here we show that phytosphingosine is metabolized to odd-numbered fatty acids and is incorporated into glycerophospholipids both in yeast and mammalian cells. Disruption of the yeast gene encoding long-chain base 1-phosphate lyase, which catalyzes the committed step in the metabolism of phytosphingosine to glycerophospholipids, causes an ~40% reduction in the level of phosphatidylcholines that contain a C15 fatty acid. We also find that 2-hydroxypalmitic acid is an intermediate of the phytosphingosine metabolic pathway. Furthermore, we show that the yeast MPO1 gene, whose product belongs to a large, conserved protein family of unknown function, is involved in phytosphingosine metabolism. Our findings provide insights into fatty acid diversity and identify a pathway by which hydroxyl group-containing lipids are metabolized.