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The primary objective was to non-invasively measure the cardiac index (CI) and associated haemodynamic parameters of healthy volunteers and their changes with age. This was a single centre, prospective, observational study of healthy volunteers aged between 20 and 59 years, using the ClearSight™ (Edwards Life Sciences, Irvine, CA, USA) device. We recorded 514 observations in 97 participants. The mean CI was 3.5 l/min/m2 (95% confidence interval [95% CI] 3.4 to 3.7 l/min/m2). The mean stroke volume index (SVI) was 47 ml/m2 (95% CI 45 to 49 ml/m2) and the mean systemic vascular resistance index was 2,242 dyne.s/cm5/m2 (95% CI 2,124 to 2,365 dyne.s/cm5/m2). There was an inverse linear relationship between increasing age and CI (P <0.0001), which decreased by 0.044 l/min/m2 (95% CI  -0.032 to -0.056 l/min/m2) per year. This change was mostly due to a decrease in SVI of 0.45 ml/m2 (95% CI 0.32 to 0.57 ml/m2) per year (P <0.0001). The mean CI of young healthy humans is approximately 3.5 l/min/m2 and declines by approximately 40 ml/min/m2 per year, mostly due to a decline in stroke volume (SV). These findings have significant implications regarding the clinical interpretation of haemodynamic parameters and the application of these results to individual patients. [ABSTRACT FROM AUTHOR]

The influence of variables that might affect the accuracy of pulse oximetry (SpO2) recordings in critically ill patients is not well established. We sought to describe the relationship between paired SpO2/SaO2 (oxygen saturation via arterial blood gas analysis) in adult intensive care unit (ICU) patients and to describe the diagnostic performance of SpO2 in detecting low SaO2 and PaO2. A paired SpO2/SaO2 measurement was obtained from 404 adults in ICU. Measurements were used to calculate bias, precision, and limits of agreement. Associations between bias and variables including vasopressor and inotrope use, capillary refill time, hand temperature, pulse pressure, body temperature, oximeter model, and skin colour were estimated. There was no overall statistically significant bias in paired SpO2/SaO2 measurements; observed limits of agreement were +/-4.4%. However, body temperature, oximeter model, and skin colour, were statistically significantly associated with the degree of bias. SpO2 <89% had a sensitivity of 3/7 (42.9%; 95% confidence intervals, CI, 9.9% to 81.6%) and a specificity of 344/384 (89.6%; 95% CI 86.1% to 92.5%) for detecting SaO2 <89%. The absence of statistically significant bias in paired SpO2/SaO2 in adult ICU patients provides support for the use of pulse oximetry to titrate oxygen therapy. However, SpO2 recordings alone should be used cautiously when SaO2 recordings of 4.4% higher or lower than the observed SpO2 would be of concern. A range of variables relevant to the critically ill had little or no effect on bias. [ABSTRACT FROM AUTHOR]

After prolonged mechanical ventilation patients may experience the 'post intensive care syndrome' (PICS) and may be candidates for post-discharge follow-up clinics. We aimed to ascertain the incidence and severity of PICS symptoms in patients surviving prolonged mechanical ventilation and to describe their views regarding follow-up clinics. In a teaching hospital, we conducted a cohort study of all adult patients discharged alive after ventilation in ICU for ≥7 days during 2013. We administered the EuroQol-5D (EQ-5D) and Hospital Anxiety and Depression Scale (HADS) via telephone interview and asked patients their views about the possible utility of a follow-up clinic. We studied 48 patients. At follow-up (average 19.5 months), seven (15%) patients had died and 14 (29%) did not participate (eight declined; two were non-English speakers; four were non-contactable). Among the 27 responders, 16 (59%) reported at least moderate problems in ≥1 EQ-5D dimension; 10 (37%) in ≥2 dimensions, and 8 (30%) in ≥3 dimensions. Moreover, 10 (37%) patients reported marked psychological symptoms; six (22%) scored borderline or abnormal on the HADS for both anxiety and depression; and four (15%) scored borderline or abnormal for one component. Finally, 21/26 (81%) patients stated that an ICU follow-up clinic would have been beneficial. At long-term follow-up, the majority of survivors of prolonged mechanical ventilation reported impaired quality of life and significant psychological symptoms. Most believed that a follow-up clinic would have been beneficial. [ABSTRACT FROM AUTHOR]

Knowledge of critical care nurses' intravenous fluid bolus therapy (FBT) practice remains underexplored. Using a multi-choice online survey conducted between September and October 2014, we sought to describe the self-reported practice of critical care nurses located in Australia and New Zealand. Two hundred and ninety-five critical care nurses responded to the survey with most practising in adult ICUs. Overall, 0.9% saline solution was the preferred solution for FBT. However, more Australian than New Zealand respondents preferred 'albumin 4%' (31% versus 3.6%, P <0.01) for FBT. In contrast, more New Zealand respondents preferred 'Plasma-Lyte®' (33.3% versus 6.4%, P <0.01). Half of the respondents defined FBT as 250 ml administered as quickly as possible. However, FBT volumes ranged from 100 ml to >1000 ml and administration duration from as quickly as possible to 60 minutes. In response to FBT, almost half of the respondents expected an increase in mean arterial pressure of between 11 to 20 mmHg. Similarly, >40% expected a central venous pressure increase >3 mmHg, >70% expected a urinary output increase of 0.5 to 1.0 ml/kg/hr, and >60% expected a decrease in heart rate of >11 /min. Overall, 0.9% saline remains the most common solution for FBT, but there are significant national differences in the preference for albumin and Plasma-Lyte. A volume of 250 ml defines a fluid bolus, with a range from 100 ml to >1000 ml, and speed of delivery from stat to 60 minutes. Most nurses expect substantial physiological effects with FBT. [ABSTRACT FROM AUTHOR]

There is little consensus on the definition or optimal constituents of fluid bolus therapy (FBT), and there is uncertainty regarding its physiological effects. The aims of this study were to determine clinician-reported definitions of FBT and to explore the physiological responses clinicians expect from such FBT. In June and October 2014, intensive care and emergency physicians in Australia and New Zealand were asked to participate in an electronic questionnaire of the reported practice and expectations of FBT. Two hundred and fifty-one questionnaires were completed, 65.3% from intensivists. We identified the prototypical FBT given by intensivists is more than 250 ml of compound sodium lactate, saline or 4% albumin given in less than 30 minutes, while that given by emergency department physicians is a similar volume of saline delivered over a similar time frame. Intensive care and emergency physicians expected significantly different changes in mean arterial pressure (P=0.001) and heart rate (P=0.033) following FBT. Substantial variation was demonstrated in the magnitude of expected response within both specialties for each variable. Major variations exist in self-reported FBT practice, both within and between acute specialties, and wide variation can be demonstrated in the expected physiological responses to FBT. International explorations of practice and prospective quantification of the actual physiological response to FBT are warranted. [ABSTRACT FROM AUTHOR]

The article reports on a survey of intensivists in New Zealand to determine their approach to the monitoring, prescription and management of risks associated with oxygen therapy. It was found that all respondents are using pulse oximetry with more than 93% of them having access to a blood gas machine within their intensive care unit. The survey showed that 61% of intensivists of assessed other indices of tissue oxygenation and 12.8% believed that oxygen toxicity was a greater threat to lung injury than barotrauma when commencing mechanical ventilation.