BackgroundLobular Capillary Hemangioma (LCH) is a benign tumour that is known to be hormone responsive and have a relatively high incidence during pregnancy, the most common site being the gingival surfaces. A tracheal origin for this tumour is extremely rare, with no case reported so far in this patient population, and the only reported clinical presentation of tracheal LCH in the literature is with haemoptysis.Case presentationWe describe a case of a 23-year-old known asthmatic who presented at 32 weeks gestation with life-threatening respiratory failure resembling acute severe asthma, requiring invasive ventilation which was extremely difficult. This was subsequently found to be due to a large tracheal LCH producing a ball-valve phenomenon and predominantly expiratory airflow limitation similar to acute asthma. The endotracheal tube was advanced past the lesion under bronchoscopic guidance, and urgent Caesarean section performed due to foetal distress. The tumour was subsequently debulked and the trachea stented, facilitated by bi-femoral veno-venous extra-corporeal membrane oxygenation with relatively low dose of heparin.ConclusionTo our knowledge, this is the first report of a unique presentation and management of largest tracheal LCH so far occurring during pregnancy. Pulmonary and critical care physicians should be aware of this unique differential of refractory asthma, the aggressive nature of this benign tumour due to hormonal influences during pregnancy, and feasibility of using bi-femoral veno-venous extra-corporeal membrane oxygenation with low dose heparin as a rescue, given the high risk of bleeding.

We hypothesised that ROTEM® (Basel, Switzerland) INTEM® (ROTEM, Basel, Switzerland) clotting time (CT) would have good agreement with activated partial thromboplastin time (aPTT) in determining whether a dose adjustment should be made to the unfractionated heparin (UFH) infusion in patients on extracorporeal membrane oxygenation. All patients treated with extracorporeal membrane oxygenation over a five-year period were included for data analysis. Retrospective analysis was performed of prospectively collected data points, wherein aPTT, activated CT and ROTEM was performed simultaneously to monitor UFH-based anticoagulation. Two hundred data points were available for analysis. Turnaround time was shortest for activated CT followed by ROTEM and aPTT. Despite achieving therapeutic aPTT targets, the majority (>50%) of INTEM CT results were within normal limits. The aPTT and INTEM CT results correlated weakly (r=0.31, 95% confidence interval [0.17, 0.43]) and there was no agreement between the directional changes of aPTT and INTEM CT results on successive days (χ2 = 2.33, P=0.17). Due to relative insensitivity, INTEM CT-guided UFH titration was estimated to result in a 289% increase in incidence of up-titration, over aPTT-guided titration. The INTEM CT results (r=0.36, 95% confidence interval [0.23, 0.48]) correlated weakly with UFH infusion rates. The UFH infusion rate only explained 13% variability in INTEM CT values. While haemorrhagic complications were frequent, no major clotting complications were encountered. Our results demonstrated that aPTT and INTEM CT do not provide equivalent information to guide UFH infusion rate titration during extracorporeal membrane oxygenation. Our study suggests caution regarding the use of ROTEM for guiding UFH-based anticoagulation as it may lead to excessive UFH exposure.

Rapid intravenous (iv) infusion of 0.9% saline alters respiratory mechanics in healthy subjects. However, the relative cardiovascular and respiratory effects of bolus iv crystalloid vs. colloid are unknown. Six healthy male volunteers were given 30 ml/kg iv 0.9% saline, 4% albumin, and 5% glucose at a rate of 100 ml/min on 3 separate days in a double-blinded, randomized crossover study. Impulse oscillometry, spirometry, lung volumes, diffusing capacity (DLCO), and blood samples were measured before and after fluid administration. Lung ultrasound B-line score (indicating interstitial pulmonary edema) and Doppler echocardiography indices of cardiac preload were measured before, midway, immediately after, and 1 h after fluid administration. Infusion of 0.9% saline increased small airway resistance at 5 Hz (P = 0.04) and lung ultrasound B-line score (P = 0.01) without changes in Doppler echocardiography measures of preload. In contrast, 4% albumin increased DLCO, decreased lung volumes, and increased the Doppler echocardiography mitral E velocity (P = 0.001) and E-to-lateral/septal e' ratio, estimated blood volume, and N-terminal pro B-type natriuretic peptide (P = 0.01) but not lung ultrasound B-line score, consistent with increased pulmonary blood volume without interstitial pulmonary edema. There were no significant changes with 5% glucose. Plasma angiopoietin-2 concentration increased only after 0.9% saline (P = 0.001), suggesting an inflammatory mechanism associated with edema formation. In healthy subjects, 0.9% saline and 4% albumin have differential pulmonary effects not attributable to passive fluid filtration. This may reflect either different effects of these fluids on active signaling in the pulmonary circulation or a protective effect of albumin.

BackgroundIn acute liver failure (ALF) therapeutic plasma exchange (TPE) improves laboratory measures of liver function. In patients with ALF requiring minimal vasoactive support TPE has also been shown to provide haemodynamic benefits including an increase in systemic blood pressure. However the haemodynamic effects of TPE in patients with severe ALF requiring moderate or high dose vasopressor therapy has not been reported. We retrospectively examined the haemodynamic effects of TPE in a cohort of patients with severe ALF requiring vasopressor therapy.MethodsPhysiological, laboratory and treatment data were collected on all patients with ALF who received TPE between January 2000 and December 2012. All patients were managed in the intensive care unit of a tertiary referral centre for ALF and liver transplantation.The primary outcome measures were changes in mean arterial pressure (MAP), vasopressor score and the ratio of vasopressor score to MAP (vasopressor dependency index (VDI)) from baseline prior to TPE through to 12 hours after completion of TPE. Secondary outcome measures were changes in other routinely collected physiological variables and laboratory results. Results are presented as median (interquartile range (IQR)). Outcome measures were evaluated using a mixed effect model.ResultsThirty nine TPE were performed in 17 patients with ALF (13 paracetamol poisoning). All TPE were performed with a centrifugal apheresis system (duration 130 minutes (IQR 115 – 147.5), plasma volume removed 5.1% body weight (IQR 4.6 – 5.5). Baseline values for primary outcome measures were: MAP 82 mmHg (IQR 72 – 92.5), vasopressor score 8.35 (IQR 3.62 – 24.6) and VDI 0.10 (IQR 0.05 – 0.31).MAP was significantly higher immediately after TPE compared to baseline (p = 0.039), however when corrected for change in vasopressor requirement there was no significant change in VDI with TPE (p = 0.953). Twelve hours after TPE the MAP, vasopressor score and VDI were not significantly different from baseline (p = 0.563, p = 0.317 and p = 0.214 respectively).ConclusionIn this cohort of patients with severe ALF centrifugal TPE did not significantly affect vasopressor requirements.Electronic supplementary materialThe online version of this article (doi:10.1186/s12871-015-0017-9) contains supplementary material, which is available to authorized users.

Recently, buffered salt solutions and 20% albumin (small volume resuscitation) have been advocated as an alternative fluid for intravenous resuscitation. The relative comparative efficacy and potential adverse effects of these solutions have not been evaluated. In a randomized, double blind, cross-over study of six healthy male subjects we compared the pulmonary and hemodynamic effects of intravenous administration of 30 ml/kg of 0.9% saline, Hartmann's solution and 4% albumin, and 6 ml/kg of 20% albumin (albumin dose equivalent). Lung tests (spirometry, ultrasound, impulse oscillometry, diffusion capacity, and plethysmography), two- to three-dimensional Doppler echocardiography, carotid applanation tonometry, blood gases, serum/urine markers of endothelial, and kidney injury were measured before and after each fluid bolus. Data were analyzed with repeated measures ANOVA with effect of fluid type examined as an interaction. Crystalloids caused lung edema [increase in ultrasound B line ( P = 0.006) and airway resistance ( P = 0.009)], but evidence of lung injury [increased angiopoietin-2 ( P = 0.019)] and glycocalyx injury [increased syndecan ( P = 0.026)] was only observed with 0.9% saline. The colloids caused greater left atrial stretch, decrease in lung volumes, and increase in diffusion capacity than the crystalloids, but without pulmonary edema. Stroke work increased proportionally to increase in preload with all four fluids ( R2 = 0.71). There was a greater increase in cardiac output and stroke volume after colloid administration, associated with a reduction in afterload. Hartmann’s solution did not significantly alter ventricular performance. Markers of kidney injury were not affected by any of the fluids administrated. Bolus administration of 20% albumin is both effective and safe in healthy subjects. NEW & NOTEWORTHY Bolus administration of 20% albumin is both effective and safe in healthy subjects when compared with other commonly available crystalloids and colloidal solution.