Hemostatic Profiles of Patients Who Underwent Transcatheter Versus Surgical Aortic Valve Replacement Versus Percutaneous Coronary Intervention

Guidelines for transcatheter aortic valve replacement (TAVR) antithrombotic prophylaxis are extrapolated predominantly from percutaneous coronary intervention (PCI) data. Here, we examined temporal coagulation changes occurring in the early perioperative period to determine the pathobiologic validity of this supposition. This was a prospective observational study of consecutive patients who underwent transfemoral TAVR (n = 27), PCI (n = 12), or surgical aortic valve replacement (SAVR) requiring cardiopulmonary bypass and cross-clamping (n = 12). Blood samples were taken at 4 time points: T1 (baseline), after general anesthesia or sedation; T2, after heparin administration; T3, at the end of the procedure; and T4, 6 hours after the procedure. The samples were assessed concurrently using standard laboratory coagulation tests and viscoelastic tests of whole blood clotting, including the latest generation thromboelastometry (ROTEM sigma) and thromboelastometry (TEG 6s). Patients in the TAVR cohort were older and a had lower baseline hemoglobin level than patients in the PCI and SAVR cohorts. The baseline platelet function was similar between the TAVR and PCI cohorts and impaired in the SAVR cohort Figure S1. The baseline hemostatic measures were comparable among cohorts. Regarding the per-patient change from baseline, the TAVR cohort showed an overall more prothrombotic state than the other cohorts, with the most marked differences from the SAVR cohort after intraoperative heparin administration and from the PCI cohorts 6 hours after the procedure. In addition, the ROTEM and TEG parameters were well correlated but not interchangeable. In conclusion, patients who underwent TAVR have a more prothrombotic hemostatic profile than PCI and SAVR patients. These findings question the current guidelines that extrapolate antithrombotic regimens from PCI to TAVR settings.

Current intraoperative storage and handling practices of autologous bypass conduit: A survey of the royal australasian college of surgeons

During bypass surgery for peripheral arterial occlusive disease and ischaemic heart disease, autologous graft conduit including great saphenous veins and radial arteries are frequently stored in solution. Endothelial damage adversely affects the performance and patency of autologous bypass grafts, and intraoperative graft storage solutions have been shown to influence this process. The distribution of storage solutions currently used amongst Cardiothoracic and Vascular Surgeons from Australia and New Zealand is not well defined in the literature. The aim of this study was to determine current practices regarding autologous graft storage and handling amongst this cohort of surgeons, and discuss their potential relevance in the context of early graft failure. From this survey, the most frequently used storage solutions were heparinized saline for great saphenous veins, and pH-buffered solutions for radial arteries. Duration of storage was 30–45 min for almost half of respondents, although responses to this question were limited. Further research is required to investigate whether ischaemic endothelial injury generates a prothrombotic state, whether different storage media can alter this state, and whether this is directly associated with clinical outcomes of interest such as early graft failure.

Nutrition adequacy, gastrointestinal and hepatic function during extracorporeal membrane oxygenation in critically ill adults: a retrospective observational study

AIMS

To identify clinical and biochemical markers associated with nutrition adequacy and gastrointestinal and liver dysfunction in adults on extracorporeal membrane oxygenation (ECMO).

METHODS

A retrospective, observational, study was conducted at 2 centres in Australia. Adult patients who received ECMO from July 2011 to June 2015 were included. Mode of ECMO used, fluid balance, number of systemic inflammatory response syndrome (SIRS) criteria present, vasoactive-inotropic scores (VIS) and liver function tests (LFTs) were collected for the duration of ECMO until 7 days after ECMO cessation. Multiple regression models were used to determine if the collected variables were associated with nutrition adequacy. The mean LFTs during ECMO were also compared to mean LFTs post ECMO cessation.

RESULTS

During the first 5 days of ECMO commencement, mean nutrition adequacy was 10% higher in the veno-venous (VV) ECMO group than in the veno-arterial (VA) group (95% confidence interval [CI], 2% to 17%). For every 5,000 ml increase of fluid balance, an associated decrease in nutrition adequacy was observed (-8%, 95% CI, -15% to -2%). A doubling of bilirubin and VIS were associated with a mean reduction in nutrition adequacy of -5% (CI -8% to -2%) and -2% (CI, -3% to -1%), respectively.

CONCLUSIONS

In the first 5 days of ECMO commencement, higher nutrition adequacy was associated with the VV mode of ECMO and reduced nutrition adequacy with increased fluid balance, more vasopressor and inotropic support and raised bilirubin. Prospective investigation is required to confirm whether these associations have a causal relationship.

Brain stem death induces pro-inflammatory cytokine production and cardiac dysfunction in sheep model

Introduction

Organs procured following brain stem death (BSD) are the main source of organ grafts for transplantation. However, BSD is associated with inflammatory responses that may damage the organ and affect both the quantity and quality of organs available for transplant. Therefore, we aimed to investigate plasma and bronchoalveolar lavage (BAL) pro-inflammatory cytokine profiles and cardiovascular physiology in a clinically relevant 6-h ovine model of BSD.

Methods

Twelve healthy female sheep (37–42 Kg) were anaesthetized and mechanically ventilated prior to undergoing BSD induction and then monitored for 6 h. Plasma and BAL endothelin-1 and cytokines (IL-1β, 6, 8 and tumour necrosis factor alpha (TNF-α)) were assessed by ELISA. Differential white blood cell counts were performed. Cardiac function during BSD was also examined using echocardiography, and cardiac biomarkers (A-type natriuretic peptide and troponin I were measured in plasma.

Results

Plasma concentrations big ET-1, IL-6, IL-8, TNF-α and BAL IL-8 were significantly (p < 0.01) increased over baseline at 6 h post-BSD. Increased numbers of neutrophils were observed in the whole blood (3.1 × 10⁹ cells/L [95% confidence interval (CI) 2.06–4.14] vs. 6 × 10⁹ cells/L [95%CI 3.92–7.97]; p < 0.01) and BAL (4.5 × 10⁹ cells/L [95%CI 0.41–9.41] vs. 26 [95%CI 12.29–39.80]; p = 0.03) after 6 h of BSD induction vs baseline. A significant increase in ANP production (20.28 pM [95%CI 16.18–24.37] vs. 78.68 pM [95%CI 53.16–104.21]; p < 0.0001) and cTnI release (0.039 ng/mL vs. 4.26 [95%CI 2.69–5.83] ng/mL; p < 0.0001), associated with a significant reduction in heart contractile function, were observed between baseline and 6 h.

Conclusions

BSD induced systemic pro-inflammatory responses, characterized by increased neutrophil infiltration and cytokine production in the circulation and BAL fluid, and associated with reduced heart contractile function in ovine model of BSD.

Randomised controlled trial of oxygen therapy and high-flow nasal therapy in African children with pneumonia

Purpose

The life-saving role of oxygen therapy in African children with severe pneumonia is not yet established.

Methods

The open-label fractional-factorial COAST trial randomised eligible Ugandan and Kenyan children aged > 28 days with severe pneumonia and severe hypoxaemia stratum (SpO₂ < 80%) to high-flow nasal therapy (HFNT) or low-flow oxygen (LFO: standard care) and hypoxaemia stratum (SpO₂ 80–91%) to HFNT or LFO (liberal strategies) or permissive hypoxaemia (ratio 1:1:2). Children with cyanotic heart disease, chronic lung disease or > 3 h receipt of oxygen were excluded. The primary endpoint was 48 h mortality; secondary endpoints included mortality or neurocognitive sequelae at 28 days.

Results

The trial was stopped early after enrolling 1852/4200 children, including 388 in the severe hypoxaemia stratum (median 7 months; median SpO₂ 75%) randomised to HFNT (n = 194) or LFO (n = 194) and 1454 in the hypoxaemia stratum (median 9 months; median SpO₂ 88%) randomised to HFNT (n = 363) vs LFO (n = 364) vs permissive hypoxaemia (n = 727). Per-protocol 15% of patients in the permissive hypoxaemia group received oxygen (when SpO₂ < 80%). In the severe hypoxaemia stratum, 48-h mortality was 9.3% for HFNT vs. 13.4% for LFO groups. In the hypoxaemia stratum, 48-h mortality was 1.1% for HFNT vs. 2.5% LFO and 1.4% for permissive hypoxaemia. In the hypoxaemia stratum, adjusted odds ratio for 48-h mortality in liberal vs permissive comparison was 1.16 (0.49–2.74; p = 0.73); HFNT vs LFO comparison was 0.60 (0.33–1.06; p = 0.08). Strata-specific 28 day mortality rates were, respectively: 18.6, 23.4 and 3.3, 4.1, 3.9%. Neurocognitive sequelae were rare.

Conclusions

Respiratory support with HFNT showing potential benefit should prompt further trials.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00134-021-06385-3.

Considerations for Antiplatelet Management of Carotid Stenting in the Setting of Mechanical Thrombectomy: A Delphi Consensus Statement

BACKGROUND AND PURPOSE

There are only few data and lack of consensus regarding antiplatelet management for carotid stent placement in the setting of endovascular stroke treatment. We aimed to develop a consensus-based algorithm for antiplatelet management in acute ischemic stroke patients undergoing endovascular treatment and simultaneous emergent carotid stent placement.

MATERIALS AND METHODS

We performed a literature search and a modified Delphi approach used Web-based questionnaires that were sent in several iterations to an international multidisciplinary panel of 19 neurointerventionalists from 7 countries. The first round included open-ended questions and formed the basis for subsequent rounds, in which closed-ended questions were used. Participants continuously received feedback on the results from previous rounds. Consensus was defined as agreement of ≥70% for binary questions and agreement of ≥50% for questions with >2 answer options. The results of the Delphi process were then summarized in a draft manuscript that was circulated among the panel members for feedback.

RESULTS

A total of 5 Delphi rounds were performed. Panel members preferred a single intravenous aspirin bolus or, in jurisdictions in which intravenous aspirin is not available, a glycoprotein IIb/IIIa receptor inhibitor as intraprocedural antiplatelet regimen and a combination therapy of oral aspirin and a P2Y12 inhibitor in the postprocedural period. There was no consensus on the role of platelet function testing in the postprocedural period.

CONCLUSIONS

More and better data on antiplatelet management for carotid stent placement in the setting of endovascular treatment are urgently needed. Panel members preferred intravenous aspirin or, alternatively, a glycoprotein IIb/IIIa receptor inhibitor as an intraprocedural antiplatelet agent, followed by a dual oral regimen of aspirin and a P2Y12 inhibitor in the postprocedural period.

Endothelin receptor antagonist improves donor lung function in an ex vivo perfusion system

BACKGROUND

A lung transplant is the last resort treatment for many patients with advanced lung disease. The majority of donated lungs come from donors following brain death (BD). The endothelin axis is upregulated in the blood and lung of the donor after BD resulting in systemic inflammation, lung damage and poor lung graft outcomes in the recipient. Tezosentan (endothelin receptor blocker) improves the pulmonary haemodynamic profile; however, it induces adverse effects on other organs at high doses. Application of ex vivo lung perfusion (EVLP) allows the development of organ-specific hormone resuscitation, to maximise and optimise the donor pool. Therefore, we investigate whether the combination of EVLP and tezosentan administration could improve the quality of donor lungs in a clinically relevant 6-h ovine model of brain stem death (BSD).

METHODS

After 6 h of BSD, lungs obtained from 12 sheep were divided into two groups, control and tezosentan-treated group, and cannulated for EVLP. The lungs were monitored for 6 h and lung perfusate and tissue samples were processed and analysed. Blood gas variables were measured in perfusate samples as well as total proteins and pro-inflammatory biomarkers, IL-6 and IL-8. Lung tissues were collected at the end of EVLP experiments for histology analysis and wet-dry weight ratio (a measure of oedema).

RESULTS

Our results showed a significant improvement in gas exchange [elevated partial pressure of oxygen (P = 0.02) and reduced partial pressure of carbon dioxide (P = 0.03)] in tezosentan-treated lungs compared to controls. However, the lungs hematoxylin-eosin staining histology results showed minimum lung injuries and there was no difference between both control and tezosentan-treated lungs. Similarly, IL-6 and IL-8 levels in lung perfusate showed no difference between control and tezosentan-treated lungs throughout the EVLP. Histological and tissue analysis showed a non-significant reduction in wet/dry weight ratio in tezosentan-treated lung tissues (P = 0.09) when compared to control.

CONCLUSIONS

These data indicate that administration of tezosentan could improve pulmonary gas exchange during EVLP.

Antiplatelet Management for Stent-Assisted Coiling and Flow Diversion of Ruptured Intracranial Aneurysms: A DELPHI Consensus Statement

BACKGROUND AND PURPOSE

There is a paucity of data regarding antiplatelet management strategies in the setting of stent-assisted coiling/flow diversion for ruptured intracranial aneurysms. This study aimed to identify current challenges in antiplatelet management during stent-assisted coiling/flow diversion for ruptured intracranial aneurysms and to outline possible antiplatelet management strategies.

MATERIALS AND METHODS

The modified DELPHI approach with an on-line questionnaire was sent in several iterations to an international, multidisciplinary panel of 15 neurointerventionalists. The first round consisted of open-ended questions, followed by closed-ended questions in the subsequent rounds. Responses were analyzed in an anonymous fashion and summarized in the final manuscript draft. The statement received endorsement from the World Federation of Interventional and Therapeutic Neuroradiology, the Japanese Society for Neuroendovascular Therapy, and the Chinese Neurosurgical Society.

RESULTS

Data were collected from December 9, 2019, to March 13, 2020. Panel members achieved consensus that platelet function testing may not be necessary and that antiplatelet management for stent-assisted coiling and flow diversion of ruptured intracranial aneurysms can follow the same principles. Preprocedural placement of a ventricular drain was thought to be beneficial in cases with a high risk of hydrocephalus. A periprocedural dual, intravenous, antiplatelet regimen with aspirin and a glycoprotein IIb/IIIa inhibitor was preferred as a standard approach. The panel agreed that intravenous medication can be converted to oral aspirin and an oral P2Y12 inhibitor within 24 hours after the procedure.

CONCLUSIONS

More and better data on antiplatelet management of patients with ruptured intracranial aneurysms undergoing stent-assisted coiling or flow diversion are urgently needed. Panel members in this DELPHI consensus study preferred a periprocedural dual-antiplatelet regimen with aspirin and a glycoprotein IIb/IIIa inhibitor.

Fresh frozen plasma and platelet concentrate storage duration not associated with in hospital mortality risk

BACKGROUND AND OBJECTIVES

To date, the effects of FFP and PC storage duration on mortality have only been studied in a few studies in limited patient subpopulations. The aim of the current study was to determine whether FFP and PC storage duration is associated with increased in hospital mortality risk across cardiac surgery, acute medicine, ICU and orthopaedic surgery patients.

MATERIALS AND METHODS

Two-stage individual patient data meta-analyses were performed to determine the effects of FFP and PC storage duration on in hospital mortality. Preset random effects models were used to determine pooled unadjusted and adjusted (adjusted for age, gender and units of product transfused) effect estimates.

RESULTS

The FFP storage duration analysis included 3625 patients across four studies. No significant association was observed between duration of storage and in hospital mortality in unadjusted analysis, but after adjusting for patient age, gender and units of product a small increased risk of in hospital mortality was observed for each additional month of storage (OR: 1·05, 95% CI: 1·01-1·08). This effect was no longer statistically significant when donor ABO blood group was incorporated into the random effects model on post hoc analyses. A total of 547 patients across five studies were incorporated in the PC storage duration analysis. No association was observed between PC storage duration and odds of in hospital morality (adjusted OR: 0·94, 95% CI: 0·79-1·11).

CONCLUSIONS

There is insufficient evidence to support shortening FFP or PC shelf life based on in hospital mortality.

Survey of Intensive Care Nurses’ Knowledge Relating to the Pulmonary Artery Catheter

In 2003 there was an increase in the use of pulmonary artery catheters in Australia from 12,000 to 16,000 units in intensive care and peri-operative care. This survey of intensive care nurses in five intensive care units in Queensland addressed knowledge of use, safety and complications of the pulmonary artery catheter, using a previously validated 31 question multiple choice survey.

One hundred and thirty-nine questionnaires were completed, a response rate of 46%. The mean score was 13.3, standard deviation ±4.2 out of a total of 31 (42.8% correct). The range was 4 to 25. Scores were significantly higher in those participants with more ICU experience, higher nursing grade, a higher self-assessed level of knowledge and greater frequency of PAC supervision. There was no significant correlation between total score and hospital- or university-based education, or total score and public or private hospital participants. Fifty-one per cent were unable to correctly identify the significant pressure change as the catheter is advanced from the right ventricle to the pulmonary artery.

Corrigendum: Sepsis: Changing Definitions, Unchanging Treatment

[This corrects the article DOI: 10.3389/fped.2018.00425.].

Neural network imaging to characterize brain injury in cardiac procedures: the emerging utility of connectomics

Cognitive dysfunction is a poorly understood but potentially devastating complication of cardiac surgery. Clinically meaningful assessment of cognitive changes after surgery is problematic because of the absence of a means to obtain reproducible, objective, and quantitative measures of the neural disturbances that cause altered brain function. By using both structural and functional connectivity magnetic resonance imaging data to construct a map of the inter-regional connections within the brain, connectomics has the potential to increase the specificity and sensitivity of perioperative neurological assessment, permitting rational individualized assessment and improvement of surgical techniques.

Platelet Storage Lesions: What More Do We Know Now?

Platelet concentrate (PC) transfusions are a lifesaving adjunct to control and prevent bleeding in cancer, hematologic, surgical, and trauma patients. Platelet concentrate availability and safety are limited by the development of platelet storage lesions (PSLs) and risk of bacterial contamination. Platelet storage lesions are a series of biochemical, structural, and functional changes that occur from blood collection to transfusion. Understanding of PSLs is key for devising interventions that prolong PC shelf life to improve PC access and wastage. This article will review advancements in clinical and mechanistic PSL research. In brief, exposure to artificial surfaces and high centrifugation forces during PC preparation initiate PSLs by causing platelet activation, fragmentation, and biochemical release. During room temperature storage, enhanced glycolysis and reduced mitochondrial function lead to glucose depletion, lactate accumulation, and product acidification. Impaired adenosine triphosphate generation reduces platelet capacity to perform energetically demanding processes such as hypotonic stress responses and activation/aggregation. Storage-induced alterations in platelet surface proteins such as thrombin receptors and glycoproteins decrease platelet aggregation. During storage, there is an accumulation of immunoactive proteins such as leukocyte-derive cytokines (tumor necrosis factor α, interleukin (IL) 1α, IL-6, IL-8) and soluble CD40 ligand which can participate in transfusion-related acute lung injury and nonhemolytic transfusion reactions. Storage-induced microparticles have been linked to enhanced platelet aggregation and immune system modulation. Clinically, stored PCs have been correlated with reduced corrected count increment, posttransfusion platelet recovery, and survival across multiple meta-analyses. Fresh PC transfusions have been associated with superior platelet function in vivo; however, these differences were abrogated after a period of circulation. There is currently insufficient evidence to discern the effect of PSLs on transfusion safety. Various bag and storage media changes have been proposed to reduce glycolysis and platelet activation during room temperature storage. Moreover, cryopreservation and cold storage have been proposed as potential methods to prolong PC shelf life by reducing platelet metabolism and bacterial proliferation. However, further work is required to elucidate and manage the PSLs specific to these storage protocols before its implementation in blood banks.

Sepsis: Changing Definitions, Unchanging Treatment

The recently revised Sepsis-3 definitions were based on criteria that were derived and validated in adult patient databases from high income countries. Both sepsis and septic shock continue to account for a substantial proportion of mortality globally, especially amongst children in low-and-middle income country settings. It is therefore urgent to develop and validate standardized criteria for sepsis that can be applied to pediatric populations in different settings, including in- and outside intensive care, both in high- and low/middle- income countries. This will be a pre-requisite to evaluate the impact of sepsis treatment strategies to improve clinical outcomes.

Acquired von Willebrand syndrome in respiratory extracorporeal life support: a systematic review of the literature

BACKGROUND AND OBJECTIVE

Venovenous extracorporeal membrane oxygenation (VV ECMO) and extracorporeal CO2 removal (ECCO2R) are increasingly used in the management of severe respiratory failure. With bleeding complications being one of the major risks of these techniques, our aim in this systematic review was to assess the available literature on acquired von Willebrand syndrome (AvWS) and extracorporeal support. AvWS has previously been associated with bleeding and shear stress.

DESIGN AND DATA SOURCES

A systematic review, using Medline via PubMed, was performed to identify eligible studies up to January 2017.

RESULTS AND CONCLUSION

The prevalence of AvWF among patients on VV ECMO or ECCO2R is high, but only a limited number of studies are reported in the literature. AvWS testing should be performed, including vWF multimer analysis, vWF activity and vWF antigen concentration. The extent to which vWF contributes to bleeding during ECMO, or how much changes in ECMO management can influence high molecular weight vWF multimer levels, cannot be answered from the currently available evidence and there remains a need for future studies.

Global tidal variations, regional distribution of ventilation, and the regional onset of filling determined by electrical impedance tomography: reproducibility

The reproducibility of the regional distribution of ventilation and the timing of onset of regional filling as measured by electrical impedance tomography lacks evidence. This study investigated whether electrical impedance tomography measurements in healthy males were reproducible when electrodes were replaced between measurements. Part 1: Recordings of five volunteers lying supine were made using electrical impedance tomography and a pneumotachometer. Measurements were repeated at least three hours later. Skin marking ensured accurate replacement of electrodes. No stabilisation period was allowed. Part 2: Electrical impedance tomography recordings of ten volunteers; a 15 minute stabilisation period, extra skin markings, and time-averaging were incorporated to improve the reproducibility. Reproducibility was determined using the Bland-Altman method. To judge the transferability of the limits of agreement, a Pearson correlation was used for electrical impedance tomography tidal variation and tidal volume. Tidal variation was judged to be reproducible due to the significant correlation between tidal variation and tidal volume (r² = 0.93). The ventilation distribution was not reproducible. A stabilisation period, extra skin markings and time-averaging did not improve the outcome. The timing of regional onset of filling was reproducible and could prove clinically valuable. The reproducibility of the tidal variation indicates that non-reproducibility of the ventilation distribution was probably a biological difference and not measurement error. Other causes of variability such as electrode placement variability or lack of stabilisation when accounted for did not improve the reproducibility of the ventilation distribution.

A 4-arm randomized controlled pilot trial of innovative solutions for jugular central venous access device securement in 221 cardiac surgical patients

PURPOSE

To improve jugular central venous access device (CVAD) securement, prevent CVAD failure (composite: dislodgement, occlusion, breakage, local or bloodstream infection), and assess subsequent trial feasibility.

MATERIALS AND METHODS

Study design was a 4-arm, parallel, randomized, controlled, nonblinded, pilot trial. Patients received CVAD securement with (i) suture+bordered polyurethane (suture + BPU; control), (ii) suture+absorbent dressing (suture + AD), (iii) sutureless securement device+simple polyurethane (SSD+SPU), or (iv) tissue adhesive+simple polyurethane (TA+SPU). Midtrial, due to safety, the TA+SPU intervention was replaced with a suture + TA+SPU group.

RESULTS

A total of 221 patients were randomized with 2 postrandomization exclusions. Central venous access device failure was as follows: suture + BPU controls, 2 (4%) of 55 (0.52/1000 hours); suture + AD, 1 (2%) of 56 (0.26/1000 hours, P=.560); SSD+SPU, 4 (7%) of 55 (1.04/1000 hours, P=.417); TA+SPU, 4 (17%) of 23 (2.53/1000 hours, P=.049); and suture + TA+SPU, 0 (0%) of 30 (P=.263; intention-to-treat, log-rank tests). Central venous access device failure was predicted (P<.05) by baseline poor/fair skin integrity (hazard ratio, 9.8; 95% confidence interval, 1.2-79.9) or impaired mental state at CVAD removal (hazard ratio, 14.2; 95% confidence interval, 3.0-68.4).

CONCLUSIONS

Jugular CVAD securement is challenging in postcardiac surgical patients who are coagulopathic and mobilized early. TA+SPU was ineffective for CVAD securement and is not recommended. Suture + TA+SPU appeared promising, with zero CVAD failure observed. Future trials should resolve uncertainty about the comparative effect of suture + TA+SPU, suture + AD, and SSD+SPU vs suture + BPU.

Nursing team leader handover in the intensive care unit contains diverse and inconsistent content: An observational study

BACKGROUND

Despite a proliferation of evidence and the development of standardised tools to improve communication at handover, evidence to guide the handover of critical patient information between nursing team leaders in the intensive care unit is limited.

OBJECTIVE

The study aim was to determine the content of information handed over during intensive care nursing team leader shift-to-shift handover.

DESIGN

A prospective observational study.

SETTING

A 21-bed medical/surgical adult intensive care unit specialising in cardiothoracic surgery at a tertiary referral hospital in Queensland, Australia.

PARTICIPANTS

Senior nurses (Grade 5 and 6 Registered nurses) working in team leader roles, employed in the intensive care unit were sampled.

METHOD

After obtaining consent from nursing staff, team leader handovers were audiotaped over 20 days. Audio recordings were transcribed and analysed using deductive and inductive content analysis. The frequency of content discussed at handover that fell within the a priori categories of the ISBAR schema (Identify-Situation-Background-Assessment-Recommendation) was calculated.

RESULTS

Forty nursing team leader handovers were recorded resulting in 277 patient handovers and a median of 7 (IQR 2) patients discussed at each handover. The majority of nurses discussed the Identity (99%), Situation (96%) and Background (88%) of the patient, however Assessment (69%) content was varied and patient Recommendations (60%) were discussed less frequently. A diverse range of additional information was discussed that did not fit into the ISBAR schema.

CONCLUSIONS

Despite universal acknowledgement of the importance of nursing team leader handover, there are no previous studies assessing its content. Study findings indicate that nursing team leader handovers contain diverse and inconsistent content, which could lead to inadequate handovers that compromise patient safety. Further work is required to develop structured handover processes for nursing team leader handovers.

Hydrodynamic evaluation of aortic cardiopulmonary bypass cannulae using particle image velocimetry

The high velocity jet from aortic arterial cannulae used during cardiopulmonary bypass potentially causes a "sandblasting" injury to the aorta, increasing the possibility of embolisation of atheromatous plaque. We investigated a range of commonly available dispersion and non-dispersion cannulae, using particle image velocimetry. The maximum velocity of the exit jet was assessed 20 and 40 mm from the cannula tip at flow rates of 3 and 5 L/min. The dispersion cannulae had lower maximum velocities compared to the non-dispersion cannulae. Dispersion cannulae had fan-shaped exit profiles and maximum velocities ranged from 0.63 to 1.52 m/s when measured at 20 mm and 5 L/min. Non-dispersion cannulae had maximum velocities ranging from 1.52 to 3.06 m/s at 20 mm and 5 L/min, with corresponding narrow velocity profiles. This study highlights the importance of understanding the hydrodynamic performance of these cannulae as it may help in selecting the most appropriate cannula to minimize the risk of thromboembolic events or aortic injury.

Protocol guided bleeding management improves cardiac surgery patient outcomes

BACKGROUND AND OBJECTIVES

Excessive bleeding is a risk associated with cardiac surgery. Treatment invariably requires transfusion of blood products; however, the transfusion itself may contribute to postoperative sequelae. Our objective was to analyse a quality initiative designed to provide an evidenced-based approach to bleeding management.

MATERIALS AND METHODS

A retrospective analysis compared blood product transfusion and patient outcomes 15 months before and after implementation of a bleeding management protocol. The protocol incorporated point-of-care coagulation testing (POCCT) with ROTEM and Multiplate to diagnose the cause of bleeding and monitor treatment.

RESULTS

Use of the protocol led to decreases in the incidence of transfusion of PRBCs (47·3% vs. 32·4%; P < 0·0001), FFP (26·9% vs. 7·3%; P < 0·0001) and platelets (36·1% vs. 13·5%; P < 0·0001). During the intra-operative period, the percentage of patients receiving cryoprecipitate increased (2·7% vs. 5·1%; P = 0·002), as did the number of units transfused (248 vs. 692; P < 0·0001). The proportion of patients who received tranexamic acid increased (13·7% to 68·2%; P < 0·0001). There were reductions in re-exploration for bleeding (5·6% vs. 3·4; P = 0·01), superficial chest wound (3·3% vs. 1·4%; P = 0·002), leg wound infection (4·6% vs. 2·0%; P < 0·0001) and a 12% reduction in mean length of stay from operation to discharge (95%: 9-16%, P < 0·0001). Acquisition cost of blood products decreased by $1 029 118 in the 15-month period with the protocol.

CONCLUSIONS

The implementation of a bleeding management protocol supported by POCCT in a cardiac surgery programme was associated with significant reductions in the transfusion of allogeneic blood products, improved outcomes and reduced cost.

The time taken for the regional distribution of ventilation to stabilise: an investigation using electrical impedance tomography

Electrical impedance tomography is a novel technology capable of quantifying ventilation distribution in the lung in real time during various therapeutic manoeuvres. The technique requires changes to the patient's position to place the electrical impedance tomography electrodes circumferentially around the thorax. The impact of these position changes on the time taken to stabilise the regional distribution of ventilation determined by electrical impedance tomography is unknown. This study aimed to determine the time taken for the regional distribution of ventilation determined by electrical impedance tomography to stabilise after changing position. Eight healthy, male volunteers were connected to electrical impedance tomography and a pneumotachometer. After 30 minutes stabilisation supine, participants were moved into 60 degrees Fowler's position and then returned to supine. Thirty minutes was spent in each position. Concurrent readings of ventilation distribution and tidal volumes were taken every five minutes. A mixed regression model with a random intercept was used to compare the positions and changes over time. The anterior-posterior distribution stabilised after ten minutes in Fowler's position and ten minutes after returning to supine. Left-right stabilisation was achieved after 15 minutes in Fowler's position and supine. A minimum of 15 minutes of stabilisation should be allowed for spontaneously breathing individuals when assessing ventilation distribution. This time allows stabilisation to occur in the anterior-posterior direction as well as the left-right direction.

Oxidative stress during extracorporeal circulation

There is an increased oxidative stress response in patients having cardiac surgery, haemodialysis or extracorporeal membrane oxygenation that is related to poorer outcomes and increased mortality. Exposure of the patients' blood to the artificial surfaces of these extracorporeal devices, coupled with inflammatory responses, hyperoxia and the pathophysiological aspects of the underlying illness itself, all contribute to this oxidative stress response. Oxidative stress occurs when there is a disruption of redox signalling and loss of control of redox balance. Ongoing oxidative stress occurring during extracorporeal circulation (ECC) results in damage to lipids, proteins and DNA and contributes to morbidity and mortality. This review discusses reactive species generation and the potential clinical consequences of oxidative stress during ECC as well as provides an overview of some current antioxidant compounds that are available to potentially mitigate the oxidative stress response.

A comprehensive ovine model of blood transfusion

BACKGROUND

The growing awareness of transfusion-associated morbidity and mortality necessitates investigations into the underlying mechanisms. Small animals have been the dominant transfusion model but have associated limitations. This study aimed to develop a comprehensive large animal (ovine) model of transfusion encompassing: blood collection, processing and storage, compatibility testing right through to post-transfusion outcomes.

MATERIALS AND METHODS

Two units of blood were collected from each of 12 adult male Merino sheep and processed into 24 ovine-packed red blood cell (PRBC) units. Baseline haematological parameters of ovine blood and PRBC cells were analysed. Biochemical changes in ovine PRBCs were characterized during the 42-day storage period. Immunological compatibility of the blood was confirmed with sera from potential recipient sheep, using a saline and albumin agglutination cross-match. Following confirmation of compatibility, each recipient sheep (n = 12) was transfused with two units of ovine PRBC.

RESULTS

Procedures for collecting, processing, cross-matching and transfusing ovine blood were established. Although ovine red blood cells are smaller and higher in number, their mean cell haemoglobin concentration is similar to human red blood cells. Ovine PRBC showed improved storage properties in saline-adenine-glucose-mannitol (SAG-M) compared with previous human PRBC studies. Seventy-six compatibility tests were performed and 17·1% were incompatible. Only cross-match compatible ovine PRBC were transfused and no adverse reactions were observed.

CONCLUSION

These findings demonstrate the utility of the ovine model for future blood transfusion studies and highlight the importance of compatibility testing in animal models involving homologous transfusions.

Stored blood transfusion induces transient pulmonary arterial hypertension without impairing coagulation in an ovine model of nontraumatic haemorrhage

BACKGROUND AND OBJECTIVES

Transfusion of blood products in particular older products is associated with patient morbidity. Previously, we demonstrated a higher incidence of acute lung injury in lipopolysaccharide-treated sheep transfused with stored blood products. As transfusion following haemorrhage is more common, we aimed to determine whether a 'first hit' of isolated haemorrhage would precipitate similar detrimental effects following transfusion and also disrupt haemostasis.

MATERIALS AND METHODS

Anaesthetized sheep had 33% of their total blood volume collected into Leukotrap bags (Pall Medical), which were processed into packed red blood cells and cross-matched for transfusion into other sheep. After 30 mins, the sheep were resuscitated with either: fresh (<5 days old) or stored (35-42 days old) ovine blood followed by 4% albumin to replacement volume, albumin alone or normal saline alone and monitored for 4 h.

RESULTS

The first hit of haemorrhage precipitated substantial decreases in mean arterial pressure however haemostasis was preserved. Transfusion of stored ovine blood induced (1) transient pulmonary arterial hypertension but no oedema and (2) reduced fibrinogen levels more than fresh blood, but neither induced coagulopathy. Thus, transfusion of stored blood affected pulmonary function even in the absence of overt organ injury.

CONCLUSION

The fact that stored blood transfusions: (1) did not induce acute lung injury in contrast to previous lipopolysaccharide-primed animal models identifies the 'first hit' as an important determinant of the severity of transfusion-mediated injury; (2) impaired pulmonary dynamics verifies the sensitivity and vulnerability of the pulmonary system to injury.

Is hyperoxaemia helping or hurting patients during extracorporeal membrane oxygenation? Review of a complex problem

Extracorporeal membrane oxygenation (ECMO) facilitates organ support in patients with refractory cardiorespiratory failure whilst disease-modifying treatments can be administered. Improvements to the ECMO process have resulted in its increased utilisation. However, iatrogenic injuries remain, with bleeding and thrombosis the most significant concerns. Many factors contribute to the formation of thrombi, with the hyperoxaemia experienced during ECMO a potential contributor. Outside of ECMO, emerging evidence associates hyperoxaemia with increased mortality. Currently, no universal definition of hyperoxaemia exists, a gap in clinical standards that may impact patient outcomes. Hyperoxaemia has the potential to induce platelet activation, aggregation and, subsequently, thrombosis through markedly increasing the production of reactive oxygen species. There are minimal data in the current literature that explore the relationship between ECMO-induced hyperoxaemia and the production of reactive oxygen species – a putative link towards pathology. Furthermore, there is limited research directly linking hyperoxaemia and platelet activation. These are areas that warrant investigation as definitive data regarding the nascence of these pathological processes may delineate and define the relative risk of supranormal oxygen tension. These data could then assist in defining optimal oxygenation practice, reducing the risks associated with extracorporeal support.

Increased sedation requirements in patients receiving extracorporeal membrane oxygenation for respiratory and cardiorespiratory failure

Critically ill patients receiving extracorporeal membrane oxygenation (ECMO) are often noted to have increased sedation requirements. However, data related to sedation in this complex group of patients is limited. The aim of our study was to characterise the sedation requirements in adult patients receiving ECMO for cardiorespiratory failure. A retrospective chart review was performed to collect sedation data for 30 consecutive patients who received venovenous or venoarterial ECMO between April 2009 and March 2011. To test for a difference in doses over time we used a regression model. The dose of midazolam received on ECMO support increased by an average of 18 mg per day (95% confidence interval 8, 29 mg, P=0.001), while the dose of morphine increased by 29 mg per day (95% confidence interval 4, 53 mg, P=0.021) The venovenous group received a daily midazolam dose that was 157 mg higher than the venoarterial group (95% confidence interval 53, 261 mg, P=0.005). We did not observe any significant increase in fentanyl doses over time (95% confidence interval 1269, 4337 µg, P=0.94). There is a significant increase in dose requirement for morphine and midazolam during ECMO. Patients on venovenous ECMO received higher sedative doses as compared to patients on venoarterial ECMO. Future research should focus on mechanisms behind these changes and also identify drugs that are most suitable for sedation during ECMO.

The interpretation of perioperative lactate abnormalities in patients undergoing cardiac surgery

Hyperlactataemia and lactic acidosis are commonly encountered during and after cardiac surgery. Perioperative lactate production increases in the myocardium, skeletal muscle, lungs and in the splanchnic circulation during cardiopulmonary bypass. Hyperlactataemia has a bimodal distribution in the perioperative period. An early increase in lactate levels, arising intraoperatively or soon after intensive care unit admission, is a familiar and concerning finding for most clinicians. It is highly suggestive of tissue ischaemia and is associated with a prolonged intensive care unit stay, a prolonged requirement for respiratory and cardiovascular support and increased postoperative mortality. Its presence should prompt a thorough search for potential causes of tissue hypoxia. In contrast, late-onset hyperlactataemia, a less well recognised complication, occurs 4 to 24 hours after completion of surgery and is typically associated with preserved cardiac output and oxygen delivery. Risk factors for late-onset hyperlactataemia include hyperglycaemia, long cardiopulmonary bypass time and elevated endogenous catecholamines. Although patients with this complication may have a longer duration of ventilation and intensive care unit length of stay than those with normolactataemia, an association with increased mortality has not been demonstrated. The discovery of late-onset hyperlactataemia should not delay the postoperative progress of an otherwise stable patient following cardiac surgery.

Cyanoacrylate tissue adhesives - effective securement technique for intravascular catheters: in vitro testing of safety and feasibility

Partial or complete dislodgement of intravascular catheters remains a significant problem in hospitals despite current securement methods. Cyanoacrylate tissue adhesives (TA) are used to close skin wounds as an alternative to sutures. These adhesives have high mechanical strength and can remain in situ for several days. This study investigated in vitro use of TAs in securing intravascular catheters (IVC). We compared two adhesives for interaction with IVC material, comparing skin glues with current securement methods in terms of their ability to prevent IVC dislodgement and inhibit microbial growth. Two TAs (Dermabond, Ethicon Inc. and Histoacryl, B. Braun) and three removal agents (Remove™, paraffin and acetone) were tested for interaction with IVC material by use of tensile testing. TAs were also compared against two polyurethane (standard and bordered) dressings (Tegaderm™ 1624 and 1633, 3M Australia Pty Ltd) and an external stabilisation device (Statlock, Bard Medical, Covington) against control (unsecured IVCs) for ability to prevent pull-out of 16 G peripheral IVCs from newborn fresh porcine skin. Agar media containing pH-sensitive dye was used to assess antimicrobial properties of TAs and polyurethane dressings to inhibit growth of Staphylococcus aureus and Staphylococcus epidermidis. Neither TA weakened the IVCs (P >0.05). Of removal agents, only acetone was associated with a significant decrease in IVC strength (P <0.05). Both TAs and Statlock significantly increased the pull-out force (P <0.01). TA was quick and easy to apply to IVCs, with no irritation or skin damage noted on removal and no bacterial colony growth under either TA.

Donation after cardiac death in Queensland: review of the pilot project

Organ transplantation is a viable therapeutic option for patients with endstage organ failure when other therapies have been exhausted. Donation after cardiac death (DCD) is re-emerging as a potential option to expand the donor pool to meet an increasing demand for organ transplantation. In this review, we evaluate the evolution of the Queensland DCD pilot project since its inception in August 2008. A retrospective analysis of registry data from Australia and New Zealand Organ Donation (ANZOD) and DonateLife Queensland was performed to collect information relating to donor characteristics, DCD process and outcomes. Data was compared with the ANZOD registry annual reports from 2008 to 2010. Twenty-three (82%) out of 28 potential DCD organ donors were successful in donating their organs. The median time from presentation to reaching consensus to withdraw cardiorespiratory support was four days (interquartile range three to eight days). The median time from withdrawal to death was 20 minutes (interquartile range 18 to 25 minutes), and the median warm ischaemia time was 17 minutes (interquartile range 14 to 19 minutes). DCD donors represented 16% (23) of the 144 deceased donors over the study period and provided approximately 10% (48) of the 505 deceased organs in Queensland. The DCD pilot project resulted in an increase in solid organ transplantation in Queensland. It allowed the development of policies to facilitate DCD, in accordance with state's legislation and DonateLife practices. If implemented state-wide, the program has the potential to be an effective way to improve organ donation rates in Queensland.

Scurvy: historically a plague of the sailor that remains a consideration in the modern intensive care unit

We report the case of the case of a 56 year old female with sepsis on a background of rheumatoid arthritis and steroid use manifesting with overt clinical features of scurvy. Ascorbic acid assays were able to demonstrate severe deficiency and confirm a diagnosis of scurvy. Clinical resolution of signs and symptoms following commencement of vitamin C replacement was rapid. The intensivist and dietitian need to consider this diagnosis even in the first world setting, particularly in the presence of sepsis, inflammatory conditions, steroid use and importantly malnutrition.

Neutrophil antibody diagnostics and screening: review of the classical versus the emerging

BACKGROUND AND OBJECTIVES  Severe transfusion-related acute lung injury (TRALI) events have been linked to donor-derived neutrophil antibodies. The journey to developing mass donor neutrophil antibody screening platforms is challenged by the fragility of neutrophils and their unique-specific antigenic characteristics. MATERIAL AND METHODS  This article critically evaluates the capabilities and potential of five emerging antibody screening platforms designed to detect neutrophil reactive antibodies relevant to TRALI. They are compared with established neutrophil serological methods. RESULTS  Data from two recombinant antigen platforms and a method using human neutrophil antigens-expressing KY cells indicated high specificity. Two mixed cellular flow cytometric assays have the advantage of presenting native conformation of the human polymorphonuclear neutrophil antigenic epitopes. CONCLUSIONS  To date, the number and specificity of test sera applied to each platform is small. This needs to be substantially increased and further rigorous serological evaluation is yet needed to compare the sensitivity and specificity limits of each new platform with classical methods. With a limited world supply of TRALI-relevant test sera, a collaborative effort of laboratories with neutrophil and TRALI investigation expertise is required.

Oxygen delivery through high-flow nasal cannulae increase end-expiratory lung volume and reduce respiratory rate in post-cardiac surgical patients

BACKGROUND

High-flow nasal cannulae (HFNCs) create positive oropharyngeal airway pressure, but it is unclear how their use affects lung volume. Electrical impedance tomography allows the assessment of changes in lung volume by measuring changes in lung impedance. Primary objectives were to investigate the effects of HFNC on airway pressure (P(aw)) and end-expiratory lung volume (EELV) and to identify any correlation between the two. Secondary objectives were to investigate the effects of HFNC on respiratory rate, dyspnoea, tidal volume, and oxygenation; and the interaction between BMI and EELV.

METHODS

Twenty patients prescribed HFNC post-cardiac surgery were investigated. Impedance measures, P(aw), ratio, respiratory rate, and modified Borg scores were recorded first on low-flow oxygen and then on HFNC.

RESULTS

A strong and significant correlation existed between P(aw) and end-expiratory lung impedance (EELI) (r=0.7, P<0.001). Compared with low-flow oxygen, HFNC significantly increased EELI by 25.6% [95% confidence interval (CI) 24.3, 26.9] and P(aw) by 3.0 cm H(2)O (95% CI 2.4, 3.7). Respiratory rate reduced by 3.4 bpm (95% CI 1.7, 5.2) with HFNC use, tidal impedance variation increased by 10.5% (95% CI 6.1, 18.3), and ratio improved by 30.6 mm Hg (95% CI 17.9, 43.3). A trend towards HFNC improving subjective dyspnoea scoring (P=0.023) was found. Increases in EELI were significantly influenced by BMI, with larger increases associated with higher BMIs (P<0.001).

CONCLUSIONS

This study suggests that HFNCs reduce respiratory rate and improve oxygenation by increasing both EELV and tidal volume and are most beneficial in patients with higher BMIs.

A novel in vivo ovine model of transfusion-related acute lung injury (TRALI)

BACKGROUND AND OBJECTIVES

Even with the introduction of specific risk-reduction strategies, transfusion-related acute lung injury (TRALI) continues to be a leading cause of transfusion-related morbidity and mortality. Existing small animal models have not yet investigated TRALI resulting from the infusion of heat-treated supernatant from whole blood platelet concentrates. In this study, our objective was the development of a novel in vivo two-event model of TRALI in sheep.

MATERIALS AND METHODS

Lipopolysaccharide (LPS; 15 μg/kg) as a first event, modelled clinical infection. Transfusion (estimated at 10% of total blood volume) of heat-treated pooled supernatant from date-of-expire human whole blood platelet concentrates (d5-PLT-S/N) was used as a second event. TRALI was defined by both hypoxaemia that developed either during the transfusion or within two hours of its completion and post-mortem histological evidence of pulmonary oedema.

RESULTS

LPS infusion did not cause lung injury itself, but did result in decreased circulating levels of lymphocytes and neutrophils with evidence of the latter becoming sequestered in the lungs. Sheep that received LPS (first event) followed by d5-PLT-S/N (second event) displayed decreased pulmonary compliance, decreased end tidal CO(2) and increased arterial partial pressure of CO(2) relative to control sheep, and 80% of these sheep developed TRALI.

CONCLUSIONS

This novel ovine two-event TRALI model presents a new tool for the investigation of TRALI pathogenesis. It represents the first description of an in vivo large animal model of TRALI and the first description of TRALI caused by transfusion with heat-treated pooled supernatant from human whole blood platelet concentrates.

Endovascular treatment of carotid blowout syndrome: who and how to treat

Carotid blowout syndrome (CBS) is a high-risk condition associated with significant morbidity and mortality that may result from invasion and destruction of the cervical carotid vasculature from head and neck squamous cell carcinoma. Endovascular approaches offer multiple modalities for treatment to prevent morbidity and death. In this paper we review our experience in addressing CBS and present an up-to-date algorithm of endovascular management. 16 lesions were identified in 8 patients treated with 9 procedures over the past year. Pseudoaneurysm and/or active extravasation were documented in at least one vessel in all 8 cases presenting with acute CBS. There were 13 pseudoaneurysms in external carotid artery (ECA) trunk (5), ECA branches (4), internal carotid artery (ICA) (1) and common carotid artery (CCA) (3). There were 3 additional ICA lesions due to tumor infiltration, resulting in ICA occlusion (2) and long segment stenosis (1). Permanent vessel occlusion was performed in 11 lesions of the ECA trunk (4), ECA branches (4) and ICA (3). Stent-grafts were placed in 5 lesions in the CCA (3), ICA (1) and ECA trunk (1). Technical success and immediate hemostasis were achieved in all patients. There were no procedural deaths or immediate complications. With a median follow-up of 2 months (range, 1-13 months), three patients died: one from recurrent CBS, one from global brain ischemia after a cardiac arrest event unrelated to CBS and one from systemic disease. There was no other recurrence of bleeding or neurological complication. Endovascular techniques offer an armamentarium to effectively address CBS, significantly affecting the care and outcome in this particular oncologic population. These techniques should be offered as early as possible in the context of a multidisciplinary approach.

Three-dimensional neurostereoendoscopy: subjective and objective comparison to 2D

Neuroendoscopic procedures, particularly transnasal skull-base procedures, are currently performed with 2D endoscopes that lack stereoscopic vision and depth of field. In principal, 3D vision should be preferable to the operating surgeon, but the previously existing systems have not been adopted. We evaluated a novel 3D endoscope to compare with 2D endoscopy. 33 neurosurgeons and skull-base otolaryngologists were recruited, and randomized to complete two runs of a task-based simulator paradigm using 2D and/or 3D visualization. After the two trials, each subject completed a questionnaire assessing professional demographics and preferences for visualization. The task paradigm had objective endpoints that measured speed, efficiency, and error rates. 75% of respondents preferred 3D endoscopy, and 87.5% determined that 3D visualization either somewhat or greatly helped with the assigned tasks. In the second run, subjects using 3D demonstrated a significantly higher efficiency than subjects using 2D (p=0.04). Subjects' speed and efficiency improved significantly when moving from 2D to 3D, and speed and efficiency improved significantly from Run 1 to Run 2 for 3D visualization. Subjective and objective outcomes support the utility of 3D visualization for neuroendoscopic techniques. Visualization that provides real-time, high-resolution binocular depth perception has a role in endoscopic skull base surgery and other neuroendoscopic procedures.

The pulmonary artery catheter in Australasia: a survey investigating intensive care physicians' knowledge and perception of future trends in use

A survey was conducted to assess the knowledge and trends of use of the pulmonary artery catheter amongst intensive care practitioners in Australasia. A 31-item multiple choice questionnaire, identical to one previously trialled in studies in the United States and Europe, was distributed to all registered intensive care specialists and trainees working in intensive care units in Australasia. Five-hundred-and-forty-one questionnaires were distributed and 151 (27.9%) were returned, with an average mark of 82.7% +/- 9.3% and a range of 53.3 to 100%. Total score was significantly associated with years of experience in intensive care (P < 0.04), number of pulmonary artery catheters inserted (P < 0.015) and whether or not the respondent had passed the Joint Faculty of Intensive Care Medicine examination (P < 0.01). Scores were significantly higher amongst trainees (P < 0.0001) and physicians who had passed the Joint Faculty of Intensive Care Medicine examination (P < 0.0001). Overall, 44.9% of respondents indicated their use of the pulmonary artery catheter was decreasing, with 42.6% indicating their use was the same over the past five years. Sixty-one percent of respondents indicated they either agreed or strongly agreed with the statement that the use of echocardiography should supersede the use of the pulmonary artery catheter by intensive care specialists in the future. We concluded that in this study, knowledge of the pulmonary artery catheter and its use is better in Australasia than in previous studies in North America and Europe. The majority of respondents in Australasia believe that echocardiography will supersede the use of the pulmonary artery catheter in the future.

Resolution of Severe Ischemia–Reperfusion Injury Post–Lung Transplantation After Administration of Endobronchial Surfactant

BACKGROUND

Ischemia-reperfusion injury (IRI) is a prominent cause of primary graft failure after lung transplantation and is associated with an altered surfactant profile. Experimental animal studies have found that replacement with exogenous surfactant administered via fiber-optic bronchoscopy (FOB) enhanced recovery from IRI with improved pulmonary compliance and gas exchange after lung transplantation. We report our clinical experience with FOB instillation of surfactant in severe IRI after human lung transplantation.

METHODS

This study is a retrospective review of 106 consecutive lung or heart-lung transplants performed at a single institution. Severe IRI was defined as diffuse roentgenographic alveolar infiltrates, worsening hypoxemia and decreased lung compliance within 72 hours of lung transplantation. One vial of surfactant (20 mg/ml phospholipid) was instilled into each segmental bronchus upon diagnosis of IRI.

RESULTS

Six patients (5 bilateral sequential and 1 re-do heart-lung transplant), mean age 46 years, were diagnosed with IRI and surfactant was administered at a mean of 37 hours (range 2.3 to 98) post-transplant. Mean graft ischemia time was 376 minutes (range 187 to 625) and cardiopulmonary bypass time 174 minutes (range 0 to 210). Mean Pao(2) [mm Hg]/Fio(2) ratio before and 48 hours after surfactant instillation was 70 and 223, respectively. Significant resolution of radiologic infiltrates was evident in all cases within 24 hours. Successful extubation occurred at a mean of 13.5 days and survival is presently 100% at 19 months (range 3 to 54).

CONCLUSIONS

Bronchoscopic instillation of surfactant improves oxygenation and prognosis after severe IRI in lung transplant recipients. It represents a cost-effective, relatively non-invasive therapeutic alternative to extracorporeal membrane oxygenation.

The use of recombinant activated factor VII for refractory bleeding post complex cardiothoracic surgery

We reviewed the outcome following use of recombinant activated factor VII (rVIIa) in patients with major bleeding post cardiothoracic surgery in our unit between January 2002 and July 2004. The unit consists of 16 cardiothoracic intensive care beds in a public metropolitan teaching hospital which serves as a referral centre for heart and lung transplant surgery. Patients with refractory bleeding following cardiothoracic surgical procedures who were treated with rVIIa were identified. A total of 12 episodes of rVIIa use were recorded in ten patients, including three episodes with ventricular assist devices, and 5 heart and/or lung transplants. The median dose used was 85 microg/kg. Chest tube drainage decreased in all patients following administration of rVlIIa; median chest tube drainage decreased from 445 ml/h to 171 ml/h (P = 0.03). Despite cessation of bleeding, mortality was high when rVIIa was used after more than 24 hours. In six episodes, despite early rVIIa use (within six hours), continued bleeding necessitated return to theatre, where a surgical source of bleeding was found. In this small retrospective study, rVIIa significantly reduced bleeding that was refractory to standard blood product transfusion. In this series of patients, those that did not respond to rVIIa early in the postoperative phase were found to have a surgical source of bleeding.

Uroscopic rainbow: modern matula medicine

Visual inspection of a patient's urine has long been used by physicians, with colour recognised as having important clinical implications. In this review the authors will revisit this ancient pastime with relevance to contemporary medical practice.

Survival following ventricular free wall rupture: a case series

Ventricular rupture occurs in 10% of acute myocardial infarctions and is associated with significant mortality. We describe two cases of ventricular rupture post myocardial infarction who survived. We highlight salient points in their diagnosis and management and review the existing literature to determine what constitutes optimal management in these difficult cases.

Aspergillus flavus endocarditis--to prevaricate is to posture

Fungal endocarditis represents both a diagnostic and therapeutic challenge to the treating team. The critical care physician will see a rising incidence as older and more immuno-compromised patients are being supported in their intensive care units. Aspergillus sp. endocarditis represents less than 25% of all cases of fungal endocarditis and is associated with a mortality of around 80%. Early diagnosis may assist with definitive management. We review a case of Aspergillus endocarditis, and review the literature as to optimal methods of detection, imaging modalities of choice, and management, both surgical and medical.