Arterial Catheter Use in the ICU: A National Survey of Antiseptic Technique and Perceived Infectious Risk.

OBJECTIVES: Recent studies have shown that the occurrence rate of bloodstream infections associated with arterial catheters is 0.9-3.4/1,000 catheter-days, which is comparable to that of central venous catheters. In 2011, the Centers for Disease Control and Prevention published new guidelines recommending the use of limited barrier precautions during arterial catheter insertion, consisting of sterile gloves, a surgical cap, a surgical mask, and a small sterile drape. The goal of this study was to assess the attitudes and current infection prevention practices used by clinicians during insertion of arterial catheters in ICUs in the United States. DESIGN: An anonymous, 22-question web-based survey of infection prevention practices during arterial catheter insertion. SETTING: Clinician members of the Society of Critical Care Medicine. SUBJECTS: Eleven thousand three hundred sixty-one physicians, nurse practitioners, physician assistants, respiratory therapists, and registered nurses who elect to receive e-mails from the Society of Critical Care Medicine. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 1,265 responses (11% response rate), with 1,029 eligible participants after exclusions were applied. Only 44% of participants reported using the Centers for Disease Control and Prevention-recommended barrier precautions during arterial catheter insertion, and only 15% reported using full barrier precautions. The mean and median estimates of the incidence density of bloodstream infections associated with arterial catheters were 0.3/1,000 catheter-days and 0.1/1,000 catheter-days, respectively. Thirty-nine percent of participants reported that they would support mandatory use of full barrier precautions during arterial catheter insertion. CONCLUSIONS: Barrier precautions are used inconsistently by critical care clinicians during arterial catheter insertion in the ICU setting. Less than half of clinicians surveyed were in compliance with current Centers for Disease Control and Prevention guidelines. Clinicians significantly underestimated the infectious risk posed by arterial catheters, and support for mandatory use of full barrier precautions was low. Further studies are warranted to determine the optimal preventive strategies for reducing bloodstream infections associated with arterial catheters.

Central sleep apnea in pregnant women with sleep disordered breathing.

PURPOSE: Physiologic changes in the cardiac, respiratory, and renal systems in pregnancy likely impact ventilatory control. Though obstructive sleep apnea and snoring are common in the pregnant population, the predisposition to central respiratory events during sleep and the prevalence of such events is less well studied. The aim of this study was to assess the presence of central apneas during sleep in pregnant women and non-pregnant controls suspected of sleep disordered breathing. METHODS: Twenty-five pregnant women referred for polysomnography for sleep disordered breathing were compared with non-pregnant controls matched for age, body mass index, gender, and apnea hypopnea index (AHI). Central apnea index was defined as the number of central apneas per hour of sleep, and mixed apnea index was defined as the number of mixed apneas per hour of sleep. RESULTS: Sixty-four percent of pregnant women had a respiratory disturbance index >5 events per hour of sleep. Mean body mass index was 44.1 ± 6.9 kg/m(2) pregnant compared to 44.0 ± 7.3 kg/m(2) in controls. The total number of central apneas observed during sleep in the pregnant group consisted of two central apneas in one patient, and of 98 central apneas in 11 patients in the control group (p = 0.05). Median central apnea index was low in both groups (pregnant 0, interquartile range (IQR) 0, 0 vs. non-pregnant 0, IQR 0, 0.2, p = 0.04). Mixed apnea index was similarly low in both groups. CONCLUSION: Despite some physiologic changes of pregnancy that impact ventilatory control, the prevalence of central sleep apnea was low in our sample of overweight pregnant women with sleep-disordered breathing.

Insertion and use of arterial catheters: a survey of clinician antiseptic technique.

RATIONALE: Recent studies have shown that the incidence of bloodstream infections (BSIs) associated with arterial catheters (ACs) is comparable to that of central venous catheters (CVCs). In 2011, the CDC published guidelines recommending the use of limited barrier precautions during AC insertion. The goal of this study was to assess the attitudes and current antiseptic techniques employed by physicians who place arterial catheters in intensive care units. METHODS: An anonymous, web-based survey was sent to critical care physicians from multiple specialties at six teaching hospitals in Rhode Island. RESULTS: Survey response rate was 33% (27/83). Only 44% of participants reported using CDC-recommended barrier precautions during AC insertion, and only 15% reported using full barrier precautions. CONCLUSIONS: Use of barrier precautions for arterial catheter insertion was inconsistent in the cohort surveyed. Less than half of physicians surveyed were in compliance with CDC guidelines. Further studies are warranted to determine the optimal preventive strategies for reducing BSIs associated with ACs.

A prophylactic fresh frozen plasma transfusion leads to a possible case of transfusion-related acute lung injury.

A 39-year-old man with cholangiocarcinoma presented with fever and abdominal pain. He was hypotensive, jaundiced and had right upper quadrant tenderness. Laboratory testing showed a leucocytosis, elevated liver function tests, total bilirubin and International Normalised Ratio (INR). Given the concern for cholangitis, the patient was given antibiotics and three units of fresh frozen plasma (FFP) before biliary drain placement. After drain placement, and within 3 h of receiving blood products, the patient became tachypnoeic and hypoxic with a chest X-ray revealing new bilateral airspace disease. The rapid development of respiratory distress was determined to most likely be transfusion-related acute lung injury (TRALI). He rapidly progressed to intubation and required 100% FiO2, high positive-end expiratory pressure (PEEP) and intermittent-prone ventilation for 48 h but eventually recovered and was extubated. TRALI is an under-recognised aetiology for respiratory distress in the critically ill. Adopting a conservative transfusion strategy may prevent TRALI.

Depressed mood predicts pulmonary rehabilitation completion among women, but not men.

BACKGROUND: As many as 30% of patients who start pulmonary rehabilitation (PR) fail to complete it, and depressed mood has been associated with PR non-completion. Depression is more common in women than men with COPD and historically women with COPD have been under studied. However, no studies to date have investigated gender-specific predictors of PR completion. METHODS: The study included 111 patients with COPD who enrolled in a community based outpatient PR program in Providence, RI. Patients who attended 20 or more sessions were designated "completers". Depression was measured using the CES-D. Logistic regression models were evaluated to test depressed mood as a predictor of PR completion. Analyses controlled for demographic and health variables found to differ between completers and non-completers. RESULTS: Patients were 95% white and 49.5% women, and 74% had a GOLD stage ≥3. Sixty-eight percent of patients were PR completers. A logistic regression model, showed that lower depressed mood independently predicted PR completion across all patients (adjusted OR = 0.92, p = .002). In gender-stratified analyses, lower depressed mood was an independent predictor of PR completion for women (adjusted OR = .91, p = .024) but not men (adjusted OR = .97, p = .45). Greater 6-min walk test distance was also an independent predictor of PR completion among women. CONCLUSION: Depressed mood is an important predictor of completion of community based PR among women. Screening and brief treatment of depression should be considered in practice.

Inhaled ß-agonist therapy and respiratory muscle fatigue as under-recognised causes of lactic acidosis.

A 49-year-old man with chronic obstructive pulmonary disease (COPD) presented with significant tachypnoea, fevers, productive cough and increased work of breathing for the previous 4 days. Laboratory data showed elevated lactate of 3.2 mEq/L. Continuous inhaled ipratropium and albuterol nebuliser treatments were administered. Lactate levels increased to 5.5 and 3.9 mEq/L, at 6 and 12 h, respectively. No infectious source was found and the lactic acidosis cleared as the patient improved. The lactic acidosis was determined to be secondary to respiratory muscle fatigue and inhaled ß-agonist therapy, two under-recognised causes of lactic acidosis in patients presenting with respiratory distress. Lactic acidosis is commonly used as a clinical marker for sepsis and shock, but in the absence of tissue hypoperfusion and severe hypoxia, alternative aetiologies for elevated levels should be sought to avoid unnecessary and potentially harmful medical interventions.

C-type natriuretic peptide does not attenuate the development of pulmonary hypertension caused by hypoxia and VEGF receptor blockade.

AIMS: C-type natriuretic peptide (CNP) is a local regulator of vascular tone and remodeling in many vascular beds. However, the role of CNP in modulating pulmonary arterial hypertensive and vascular remodeling responses is unclear. The purpose of this study was to determine if CNP is capable of preventing the development of pulmonary hypertension (PH). MAIN METHODS: We used animal models of PH caused by chronic hypoxia alone or in combination with the vascular endothelial growth factor (VEGF) receptor blocker SU5416. We measured pulmonary hemodynamics, right ventricular hypertrophy and vascular remodeling effects in response to a continuous infusion of low dose or high dose CNP or vehicle placebo. KEY FINDINGS: Right ventricular hypertrophy and a marked elevation in right ventricular systolic pressure (RVSP) were seen in both models of PH. Rats treated with the combination of SU5416 and chronic hypoxia also developed pulmonary endothelial hyperproliferative lesions. Continuous intravenous infusion of CNP at either dose did not attenuate the development of PH, right ventricular hypertrophy or vascular remodeling in either of the models of PH despite a three-fold increase in serum CNP levels. SIGNIFICANCE: CNP does not prevent the development of PH in the chronic hypoxia or SU5416 plus hypoxia models of pulmonary hypertension suggesting that CNP may not play an important modulatory role in human PH.

Activation of endothelial BKCa channels causes pulmonary vasodilation.

BACKGROUND: Large-conductance Ca(2+)-activated K(+) (BK(Ca)) channels cause hyperpolarization and can regulate vascular tone. In this study, we evaluated the effect of endothelial BK(Ca) activation on pulmonary vascular tone. METHODS: The presence of BK(Ca) channels in lung microvascular endothelial cells (LMVEC) and rat lung tissue was confirmed by RT-PCR, immunoblotting and immunohistochemistry. Isolated pulmonary artery (PA) rings and isolated ventilated-perfused rat lungs were used to assay the effects of BK(Ca) channel activation on endothelium-dependent vasodilation. RESULTS: Immunoblotting and RT-PCR revealed the presence of BK(Ca) channel alpha- and beta(4)-subunits in LMVEC. Immunohistochemical staining showed BK(Ca) channel alpha-subunit expression in vascular endothelium in rat lungs. In arterial ring studies, BK(Ca) channel activation by NS1619 enhanced endothelium-dependent vasodilation that was attenuated by tetraethylammonium and iberiotoxin. In addition, activation of BK(Ca) channels by C-type natriuretic peptide caused endothelial-dependent vasodilation that was blocked by iberiotoxin, L-NAME, and lanthanum. Furthermore, BK(Ca) activation by NS1619 caused a dose-dependent reduction in PA pressures that was attenuated by L-NAME. In vitro, BK(Ca) channel activation in LMVEC caused hyperpolarization and increased NO production. CONCLUSIONS: Pulmonary endothelium expresses BK(Ca) channels. Activation of endothelial BK(Ca) channels causes hyperpolarization and NO mediated endothelium-dependent vasodilation in micro- and macrovasculature in the lung.