Pulse pressure within the first 2 days of veno-arterial extracorporeal membrane oxygenation is predictive of death prior to hospital discharge, renal dysfunction requiring dialysis and pulmonary oedema.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) flows are titrated to achieve adequate perfusion while attempting to ideally maintain arterial pulse pressure (PP). We assessed risk in patients with low PP defined as <10 mmHg within the first 2 days of support. METHODS: Demographics, haemodynamics, echocardiographic and radiological findings were recorded retrospectively in cases conducted between 2014 and 2016. Outcomes were hospital mortality, requirement for renal replacement therapy (RRT) and severe pulmonary oedema (PO). RESULTS: Of 101 patients, 66.3% were male, mean age was 56 (range 18-71 years), mean duration of support was 6.3 days ± 4.1 days, 37.6% died prior to hospital discharge, 39.6% needed RRT and 11.9% had severe PO. Areas under the receiver operating curves of PP at 48 h for hospital mortality, RRT and severe PO were (respectively): 0.69 (95% CI 0.58-0.80, p = .001), 0.64 (95% CI 0.50-0.77, p = .044), 0.69 (95% CI 0.55-0.82, p = .009). The odds ratio for mortality, RRT, severe PO for those with low PP were (respectively) 2.8 (95% CI 1.01-7.5, p = .04), 3.1 (95% CI 1.11-8.40, p = .026), 7.6 (95% CI 2.06-27.89, p = .001). Central venous pressure, mean arterial pressure were not predictive. CONCLUSION: PP during the first 2 days of support is predictive of clinically important outcomes in patients supported with VA-ECMO.

CNS Complications in Adult Patients Treated With Extracorporeal Membrane Oxygenation.

OBJECTIVES: To describe the incidence and outcomes of radiologically confirmed acute CNS complications in extracorporeal membrane oxygenation patients at an Australian extracorporeal membrane oxygenation referral center and identify associated patient characteristics. DESIGN: Retrospective cohort study. SETTING: Single-center tertiary institution. PATIENTS: Four-hundred twelve consecutive adult patients supported with extracorporeal membrane oxygenation from 2009 to 2017. RESULTS: Fifty-five patients (13.3%) had a CNS complication confirmed by CT or MRI, including ischemic stroke (7.0%), intracerebral hemorrhage (3.4%), hypoxic ischemic encephalopathy (3.6%), and spinal cord injury (1.2%). CNS complication rates in the venoarterial, venovenous, and veno-pulmonary artery extracorporeal membrane oxygenation subgroups were 18.0%, 4.6%, and 13.6%, respectively. Neurologic complications were independently associated with the use of venoarterial extracorporeal membrane oxygenation (p = 0.002) and renal replacement therapy (p = 0.04). Sixty-five percent of patients with a neurologic complication died during their hospital admission compared with 32% of patients without this complication (p < 0.001). Venoarterial extracorporeal membrane oxygenation, renal replacement therapy, and days of extracorporeal membrane oxygenation support were also associated with hospital mortality and remained so after adjustment in a multivariable regression model (p = 0.01, p < 0.001, and p = 0.003, respectively). CONCLUSIONS: CNS complications appear to occur more frequently in patients requiring circulatory as opposed to respiratory support on extracorporeal membrane oxygenation and are independently associated with mortality. It remains unclear if these complications are causative of a poor outcome or a marker of severity of the underlying condition. Further research is required to better elucidate modifiable or preventable aspects through better patient selection and change in ongoing care.

Mechanical Ventilation Management during Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome. An International Multicenter Prospective Cohort.

Rationale: Current practices regarding mechanical ventilation in patients treated with extracorporeal membrane oxygenation (ECMO) for acute respiratory distress syndrome are unknown.Objectives: To report current practices regarding mechanical ventilation in patients treated with ECMO for severe acute respiratory distress syndrome (ARDS) and their association with 6-month outcomes.Methods: This was an international, multicenter, prospective cohort study of patients undergoing ECMO for ARDS during a 1-year period in 23 international ICUs.Measurements and Main Results: We collected demographics, daily pre- and per-ECMO mechanical ventilation settings and use of adjunctive therapies, ICU, and 6-month outcome data for 350 patients (mean ± SD pre-ECMO PaO2/FiO2 71 ± 34 mm Hg). Pre-ECMO use of prone positioning and neuromuscular blockers were 26% and 62%, respectively. Vt (6.4 ± 2.0 vs. 3.7 ± 2.0 ml/kg), plateau pressure (32 ± 7 vs. 24 ± 7 cm H2O), driving pressure (20 ± 7 vs. 14 ± 4 cm H2O), respiratory rate (26 ± 8 vs. 14 ± 6 breaths/min), and mechanical power (26.1 ± 12.7 vs. 6.6 ± 4.8 J/min) were markedly reduced after ECMO initiation. Six-month survival was 61%. No association was found between ventilator settings during the first 2 days of ECMO and survival in multivariable analysis. A time-varying Cox model retained older age, higher fluid balance, higher lactate, and more need for renal-replacement therapy along the ECMO course as being independently associated with 6-month mortality. A higher Vt and lower driving pressure (likely markers of static compliance improvement) across the ECMO course were also associated with better outcomes.Conclusions: Ultraprotective lung ventilation on ECMO was largely adopted across medium- to high-case volume ECMO centers. In contrast with previous observations, mechanical ventilation settings during ECMO did not impact patients' prognosis in this context.

Effects of extracorporeal membrane oxygenation pump flow, backflow cannulae, mean arterial blood pressure, and pulse pressure on Doppler-derived flow velocities of the lower limbs in patients on peripheral veno-arterial extracorporeal membrane oxygenation: A pilot study.

BACKGROUND: Reported rates of limb ischaemia on peripheral veno-arterial extracorporeal membrane oxygenation (pVA ECMO) vary from 1-52%. OBJECTIVES: Primary: To explore (i) the feasibility for appropriately trained intensive care unit staff to measure Doppler derived flow velocities of the lower limbs for patients on pVA ECMO; and (ii) whether these measurements are clinically useful. Secondary: explore the relationship between ECMO pump flow, backflow cannulae (BFC) properties, mean arterial blood pressure (MAP), and pulse pressure on flow velocities. METHOD: Inclusion criteria: age>18 years, on pVA ECMO >24 hours. EXCLUSION CRITERIA: any guardianship limitations and patients without a BFC. Serial patients receiving pVA-ECMO over a 10 month period had Doppler derived flow velocities of the lower limbs sampled. Simultaneously, other pertinent parameters were recorded. 80% inclusion was considered clinically feasible. Study personnel were asked for feedback regarding the ease and usefulness of studies. RESULTS: 15 of 17 patients were included: 88% inclusion. Mean peak systolic velocity (PSV) in the cannulated limb was 31 ± 29 cm/s in the dorsalis pedis (DP) and 27 ± 18 cm/s posterior tibial (PT). Similar flows were recorded in the non-cannulated limbs (DP 34 ± 29 cm/s, PT 44 ± 36 cm/s; P > 0.05). PSV was positively correlated with pulse pressure in cannulated and non-cannulated limbs respectively (r=0.63, P < 0.05; r=0.67 and P < 0.05). There was no significant correlation between PSV and MAP. ECMO pump flow and BFC were negatively correlated with PSV (r=-0.51, P < 0.05; r=-0.43, P < 0.05). CONCLUSION: It is generally feasible for ICU staff to measure flow velocities of the lower limbs for patients on pVA ECMO. It remains unclear how clinically useful these measurements are. Doppler derived flow velocities of arteries of the lower limbs of patients on pVA ECMO appear different to non-ECMO patients. PSV in the lower limbs of patients on pVA ECMO seems to be more related to pulse pressure than to other haemodynamic parameters.

A retrospective audit of insulin infusion management involving a locally developed dynamic insulin infusion guideline in a tertiary ICU.

BACKGROUND: The ideal target blood glucose range for intensive care patients on insulin infusions is controversial. Avoidance of hyperglycaemia and hypoglycaemia are well supported goals. METHODS: An audit of insulin infusion management was conducted following the institution of an insulin infusion guideline in a tertiary adult intensive care unit (ICU). The primary aim was to evaluate this guideline for safety and efficacy. Secondary aims were to compare outcomes such as ICU and hospital mortality, rate of severe hypoglycaemia, length of time within target zones, length of stay in ICU and hospital, ventilator hours and use of renal replacement therapy. Data analysis involved descriptive statistical techniques to allow comparison with other reported outcomes. RESULTS: Thirty-eight (38) patients were included, representing 137 days of insulin infusions and 2537 blood glucose readings. The mean insulin infusion treatment time was 86.4h (sd ± 86.4), median 48 h (IQR 14.4-141.6). The mean insulin dose per day was 97.6 units (sd ± 115.7), with a median of 68.7 (IQR 38.9-108.3). Blood glucose level (BGL) readings were within the desired target (6-9 mmols/L) and/or the buffer zones (4-6 and 9-12 mmols/L), 92.3% of the time. There were no episodes of severe hypoglycaemia (BGL ≤ 2.2 mmols/L). The median length of ICU stay was 5.9 days. Eighty-four (84) % of the cohort received mechanical ventilation and 26% received renal replacement therapy. The mean ventilation and renal replacement duration were days 6.9 and 9.4 days, respectively. The ICU and hospital mortality was 13.2% and 18.4%, respectively. CONCLUSION: The use of this locally developed insulin infusion guideline for hyperglycaemia within this ICU appears safe and effective. When compared to related published randomised controlled trials, the outcomes of this small scale single centre retrospective audit appear congruent. It achieved a severe hypoglycaemic rate of zero, with BGLs within target and buffer zones greater than 90%. It may be worthwhile for intensive care units to consider evaluating their own locally developed insulin infusion guidelines to ensure safety and efficacy.

Medication Error Minimization Scheme (MEMS) in an adult tertiary intensive care unit (ICU) 2009-2011.

INTRODUCTION: The Medication Error Minimisation Scheme (MEMS) is a locally based ongoing multidisciplinary, multifaceted quality improvement (QI) project within an Australian adult tertiary level Intensive Care Unit (ICU). The project commenced in 2009. Its primary aim is to enhance medication safety within this ICU by utilising existing resources. The aim of this paper is to provide a descriptive account of the various activities, interventions and results of this project within the first three years. METHODS: The research design for this project was based upon Plan-Do-Study-Act (PDSA) cycles associated with QI projects. Medication error rates and audits of: intravenous infusions, incompatible intravenous medications and incorrect documentation of withheld medications were analyzed according to simple statistical techniques. Initial and follow up medication safety surveys were compared using basic statistical analysis. Focus groups exploring barriers and enablers of medication incident reporting were analyzed according to qualitative techniques associated with focus group discussions. Other interventions included: regular education sessions; discussions within other departmental meetings such as nursing staff meetings and Morbidity and Mortality meetings; and bedside discussions and demonstrations. Promotion of medication safety occurred within a number of forums; activities and findings were advertised and displayed; a recognizable Logo for MEMS was employed; and incentives were provided for staff. RESULTS: Reported Medication Incidents (MIs) increased from 6.2 to 14.9 MIs per 1000 patient days. Audits and chart reviews confirmed that more MIs are uncovered by employing a variety of techniques in addition to incident reporting. Staff surveys provided a rich source of information regarding medication safety. Audits of intravenous infusions revealed a reduced error rate from 38/331 (11.5%) to 15/468 (3.2%). Chart review of incorrect documentation of omitted medications decreased from 105/347 (30.3%) to 104/486 (21.4%). Focus groups provided information that was able to be used in a number of hospital forums in order to explain the impact of existing systems upon ICU staff. CONCLUSION: This ongoing QI project was able to achieve its targeted goals. The MI reporting rate was increased. This project demonstrated that measurable, "non-incident report" errors can be reduced by focusing upon and promoting medication safety in the ICU. These activities demonstrated a workplace that values medication safety, the discovery of shortfalls and the benefits of ongoing improvement.

The effect of a structured ECPR protocol aided by specific simulation training in a quaternary ECMO centre: A retrospective pre-post study.

Background: There is limited literature exploring the relationship between simulation training and extracorporeal cardiopulmonary resuscitation (ECPR) outcomes. We examined whether there was an association between the implementation of an in situ simulation training program and ECPR utilisation, time to extracorporeal membrane oxygenation (ECMO), and neurologically intact survival. Methods: In this retrospective pre-post study of in-hospital cardiac arrests (IHCA) and out-of-hospital cardiac arrests (OHCA), we analysed data for all patients recorded as receiving ECPR from September 2009 to December 2020 at our institution, relative to the implementation of an in situ ECPR simulation training program and a standardised procedure for high-quality ECPR. The primary outcome was Cerebral Performance Category (CPC) 1 or 2 at hospital discharge. Results: There were 27 patients in the pre-intervention period and 39 patients in the post-intervention period. The median ECPR rate per year was 2 pre-intervention and 7 post-intervention (p = 0.073). There was an association between the implementation of the program and decreased median time from OHCA to ECMO flow, from 87 (IQR 78-95) minutes pre-intervention to 70 (IQR 69-72) minutes post-intervention (p = 0.002). Median time from IHCA to ECMO flow was 40 (IQR 20-75) minutes pre-intervention and 28 (IQR 16-41) minutes post-intervention (p = 0.134). Survival with CPC 1 or 2 was 7/27 (25.9%) pre-intervention and 15/39 (38.5%) post-intervention (p = 0.288). Conclusion: We observed an association between the implementation of an ECPR-specific simulation program and decreased time from OHCA to ECMO flow. There was no association between the implementation of the program and neurologically intact survival at hospital discharge.

Early experience of a new extracorporeal carbon dioxide removal device for acute hypercapnic respiratory failure.

BACKGROUND: Recent advances in the technology of extracorporeal respiratory assist systems have led to a renewed interest in extracorporeal carbon dioxide removal (ECCOR). The Hemolung is a new, low-flow, venovenous, minimally invasive, partial ECCOR device that has recently been introduced to clinical practice to aid in avoiding invasive ventilation or to facilitate lung-protective ventilation. OBJECTIVE: We report our early experience on use, efficacy and safety of the Hemolung in three Australian intensive care units. METHODS: Retrospective review of all patients with acute or acute-on-chronic respiratory failure (due to chronic obstructive pulmonary disease [COPD] with severe hypercapnic respiratory failure when non-invasive ventilation failed; acute respiratory distress syndrome; COPD; or asthma when lung-protective ventilation was not feasible due to hypercapnia) for whom the Hemolung was used. RESULTS: Fifteen patients were treated with ECCOR. In four out of five patients, the aim of avoiding intubation was achieved. In the remaining 10 patients, the strategy of instituting lung-protective ventilation was successful. The median duration for ECCOR was 5 days (interquartile range, 3-7 days). The pH and PCO2 improved significantly within 6 hours of instituting ECCOR, in conjunction with a significant reduction in minute ventilation. The CO2 clearance was 90-100 mL/min. A total of 93% of patients survived to weaning from ECCOR, 73% survived to ICU discharge and 67% survived to hospital discharge. CONCLUSION: Our data shows that ECCOR was safe and effective in this cohort. Further experience is vital to identify the patients who may benefit most from this promising therapy.

Registered nurses' lived experience of advocacy within a critical care unit: a phenomenological study.

Anecdotally, it has often been expressed by registered nurses (RNs) working within critical care environments that they are patient advocates. However, to date, little systematic research has been undertaken to validate this assertion. Thus this project, which explored the lived experience of RNs working within a critical care unit in a country area of Australia, was conceived. The five participants of this study were all Division 1 RNs possessing a critical care certificate and a minimum of 4 years' nursing experience. Through their participation in an in-depth audiotaped interview they revealed a wealth of experiences and ideas about their involvement as patient advocates. The results of this research indicate that the phenomenon of nurse advocacy is a multi-faceted process and embraces many kinds of activities that nurses engage in on behalf of their clients. The findings of this study indicate that some of the participants' experiences are congruent with elements of advocacy contained within the nursing literature and statements of professional nursing bodies. However, there are some findings in this study that are not consistent with available literature. For instance, these participants markedly reject the notion that advocacy is an inappropriate concept for nurses, despite suggestions in the literature that this is an inappropriate role. Instead they wholeheartedly embrace this role, asserting it as central to their practice. Further, although the literature identifies potential controversies regarding enactment of the role of advocacy, the participants of this study are silent on these matters. It is not known what this silence implies and, in light of the study findings, it is recommended that nursing organisations, theorists and clinicians consider whether it is worthwhile to more clearly confirm the nature and role of advocacy within Australian nursing.

Sedation practice in veno-venous extracorporeal membrane oxygenation: an international survey.

Sedation practice in extracorporeal membrane oxygenation (ECMO) is challenging, and some studies suggest that pharmacokinetics of sedative drugs are altered by the circuitry components. We conducted an international survey of sedation practice in centers offering veno-venous ECMO for adult patients in collaboration with the Extracorporeal Life Support Organization. A total 102 respondents participated representing various experienced centers from around the world. Fifty-eight percent responded that patients on ECMO have a higher or much higher sedation requirement than other critically ill patients, whilst 51% achieved a responsive or cooperative level of sedation. Midazolam (79%), morphine (43%) and fentanyl (45%) were most frequently used. Alpha-2 agonists were prescribed in 66% while propofol was used infrequently (36%). Thirty-five percent did not use continuous muscle relaxants. Responses from experienced users differed to those who reported less experience. Sedation practice in ECMO varies widely. Cooperative or responsive levels of sedation can frequently be achieved, and the drugs used differ from those used in non-ECMO patients.