Supporting hemodynamics: what should we target? What treatments should we use?

Assessment and monitoring of hemodynamics is a cornerstone in critically ill patients as hemodynamic alteration may become life-threatening in a few minutes. Defining normal values in critically ill patients is not easy, because 'normality' is usually referred to healthy subjects at rest. Defining 'adequate' hemodynamics is easier, which embeds whatever pressure and flow set is sufficient to maintain the aerobic metabolism. We will refer to the unifying hypothesis proposed by Schrier several years ago. Accordingly, the alteration of three independent variables - heart (contractility and rate), vascular tone and intravascular volume - may lead to underfilling of the arterial tree, associated with reduced (as during myocardial infarction or hemorrhage) or expanded (sepsis or cirrhosis) plasma volume. The underfilling is sensed by the arterial baroreceptors, which activate primarily the sympathetic nervous system and renin-angiotensin-aldosterone system, as well as vasopressin, to restore the arterial filling by increasing the vascular tone and retaining sodium and water. Under 'normal' conditions, therefore, the homeostatic system is not activated and water/sodium excretion, heart rate and oxygen extraction are in the range found in normal subjects. When arterial underfilling occurs, the mechanisms are activated (sodium and water retention) - associated with low central venous oxygen saturation (ScvO₂) if underfilling is caused by low flow/hypovolemia, or with normal/high ScvO₂ if associated with high flow/hypervolemia. Although the correction of hemodynamics should be towards the correction of the independent determinants, the usual therapy performed is volume infusion. An accepted target is ScvO₂ >70%, although this ignores the arterial underfilling associated with volume expansion/high flow. For large-volume resuscitation the worst solution is normal saline solution (chloride load, strong ion difference = 0, acidosis). To avoid changes in acid-base equilibrium the strong ion difference of the infused solution should be equal to the baseline bicarbonate concentration.     

Rational fluid management in today's ICU practice

Intravenous fluid therapy has evolved significantly over time. From the initial report of the first intravenous administration of sodium-chloride-based solution to the development of goal-directed fluid therapy using novel dynamic indices, efforts have focused on improving patient outcomes. The goal of this review is to provide a brief overview of current concepts for intravenous fluid administration in the ICU. Results of recently published clinical trials suggesting harmful effects of starch-based solutions on critically ill patients are discussed. Concepts for goal-directed fluid therapy and new modalities for the assessment of fluid status as well as for the prediction of responsiveness to different interventions will continue to emerge. Advances in technology will have to be critically evaluated for their ability to improve outcomes in different clinical scenarios.     

Ethical Considerations in the Neonatal Intensive Care Unit

Advances in treatment and technology capabilities, coupled with the ability to care for younger, smaller, and sicker neonates contribute to ethical conflicts in the neonatal intensive care unit (NICU). Although the ethical approach to care is sometimes inconsistent, it is important for clinicians to develop and adopt a framework for ethical decision-making in the NICU. Providers need to understand the four ethical principles of autonomy, beneficence, nonmaleficence, and justice and apply these principles to clinical decision-making about care in the NICU. Ethical decision-making must be family-centered and respectful of cultural differences. Providers must comply with professional ethical guidelines as well as government and legal mandates. Adopting ethical frameworks for neonatal care ensures a more holistic approach to care in the highly technical environment of the NICU.     

A Glance at the Future of Cultural Competency in Healthcare

Cultural competency was first articulated in the 1980s to address the issues of discrimination and disparities in the provision of healthcare services. Since then, countless efforts have been made to educate and train a culturally competent healthcare task force. As the current US government unveils its healthcare reform, one might wonder what will be the future of the cultural competency in health care. The question is even more pertinent if the upcoming demographic shift of the US population is added to the picture. The most recent data from the Census Bureau stated that Asians and Hispanics are the fastest-growing ethnic groups in the US population.¹ Therefore the majority of the patients receiving primary and preventive care under the changes with the Affordable Care Act will be among today’s minority groups. So more than ever before, time needs to be spent on analysis and discussion of how these important changes will shape the quality of care that ought to be culturally sensitive as an aspect of delivery of excellent care.