Faculty Bibliography

BACKGROUND.Abnormal central venous oxygen saturation (ScvO2) reflects an disbalance between oxygen demand and oxygen supply.In addition, weaning from mechanical ventilation by a spontaneous breathing trial (SBT) results in a significant increase in oxygen demand.Therefore, we hypothesized that the presence of low ScvO2 at the beginning of SBT would be a risk factor for weaning failure.METHODS.In a multicenter observational study, patients mechanically ventilated for more than 24h and clinically ready for a SBT were studied.Study variables were recorded at baseline, 2min, 30min, and at the end of the SBT.Decisions to extubate where taken by the attending physician based on their usual practice without knowledge of ScvO2 levels.Weaning failure was defined as a decision not to extubate at the end of the SBT, or reintubation within 48h after extubation.The baseline values of ScvO2 were categorized in quartiles.One-way ANOVA test and kruskal wallis test were used to analyze parametric and nonparametric continuous variables.A Chi-square test was used for qualitative variables.Multivariate regression analysis (corrected for the presence of a history of cardiac dysfunction) was used to find independent associations between ScvO2 and weaning failure.RESULTS.204 patients from 5 centers were included.Demographic and clinical characteristic are show in the Table 192.156 (76%) patients were successfully weaned.Of the patients that failed weaning (n = 48), 37 (77%) were not extubated at the end of the SBT, and 11 (23%) were reintubated within 48h.At baseline patients that failed to wean had lower central venous pressure, higher respiratory rate, and lower ScvO2 (Table 192).Sixty patients (29%) patients had a ScvO2 less than 70%.Multivariate regression analysis revealed the 25th quartile (ScvO2 = 63 +/- 4%) to be an independent risk factor for weaning failure OR 2.78 95% CI (1.09-7.08; P = 0.03).No other variables recorded were related to weaning failure.CONCLUSIONS.In a mixed group of critically ill patients ready for a SBT after at least 24h of mechanical ventilation, a low ScvO2 at the start of the SBT was an independent risk factor for a failure to wean

PURPOSE OF REVIEW: A discussion of recent research exploring the feasibility of perfusion-guided resuscitation of acute circulatory failure with a focus on lactate and microcirculation. RECENT FINDINGS: Upon diagnosis of shock, hyperlactemia is associated with poor outcome and, under appropriate clinical circumstances, may reflect inadequate tissue perfusion. Persistent hyperlactemia despite resuscitation is even more strongly correlated with morbidity and mortality. Importantly, there is minimal coherence between lactate trends and static hemodynamic measures such as blood pressure, especially after the initial, hypovolemic phase of shock. During this early period, lactate guided-resuscitation is effective and possibly superior to hemodynamic-guided resuscitation. Similar to hyperlactemia, impaired microcirculation is ubiquitous in shock and is evident even in the setting of hemodynamic compensation (i.e., occult shock). Moreover, persistent microcirculatory derangement is associated with poor outcome and may reflect ongoing shock and/or long-lasting damage. Although the wait continues for a microcirculation-guided resuscitation trial, there is progress toward this goal. SUMMARY: Although questions remain, a multimodal perfusion-based approach to resuscitation is emerging with lactate and microcirculation as core measures. In this model, hyperlactemia and microcirculatory derangement support the diagnosis of shock, may help guide resuscitation during the initial period, and may reflect resuscitation efficacy and iatrogenic harm (e.g., fluid overload).

OBJECTIVE: Many patients are admitted to the ICU at or near the end of their lives. Consequently, the increasingly common debate regarding physician-assisted suicide and euthanasia holds implications for the practice of critical care medicine. The objective of this article is to explore core ethical issues related to physician-assisted suicide and euthanasia from the perspective of healthcare professionals and ethicists on both sides of the debate. SYNTHESIS: We identified four issues highlighting the key areas of ethical tension central to evaluating physician-assisted suicide and euthanasia in medical practice: 1) the benefit or harm of death itself, 2) the relationship between physician-assisted suicide and euthanasia and withholding or withdrawing life support, 3) the morality of a physician deliberately causing death, and 4) the management of conscientious objection related to physician-assisted suicide and euthanasia in the critical care setting. We present areas of common ground and important unresolved differences. CONCLUSIONS: We reached differing positions on the first three core ethical questions and achieved unanimity on how critical care clinicians should manage conscientious objections related to physician-assisted suicide and euthanasia. The alternative positions presented in this article may serve to promote open and informed dialogue within the critical care community.

BACKGROUND: Delirium is a common form of vital organ dysfunction in intensive care unit (ICU) patients and is associated with poor outcomes. Adherence to guideline recommendations pertaining to delirium is still suboptimal. AIMS: We performed a survey aimed at identifying barriers for implementation that should be addressed in a tailored implementation intervention targeted at improved ICU delirium guideline adherence. DESIGN: The survey was conducted among ICU professionals. METHODS: An online survey was conducted among 360 ICU health care professionals (nurses, physicians and delirium consultants) from six ICUs in the southwest of the Netherlands as part of a multicentre prospective implementation project [response rate: 64% of 565 invited; 283 (79%) were nurses]. RESULTS: Although the majority (83%) of respondents considered delirium a common and major problem in the ICU, we identified several barriers for implementation of a delirium guideline. The most important barriers were knowledge deficit, low delirium screening rate, lack of trust in the reliability of delirium screening tools, belief that delirium is not preventable, low familiarity with delirium guidelines, low satisfaction with physician-described delirium management, poor collaboration between nurses and physicians, reluctance to change delirium care practices, lack of time, disbelief that patients would receive optimal care when adhering to the guideline and the perception that the delirium guideline is cumbersome or inconvenient in daily practice. CONCLUSION: Although ICU professionals consider delirium a serious problem, several important barriers to adhere to guidelines on delirium management are still present today. RELEVANCE TO CLINICAL PRACTICE: Identification of implementation barriers for adherence to guidelines pertaining to delirium is feasible with a survey. Results of this study may help to design-targeted implementation strategies for ICU delirium management.