Evaluating models of consent in changing health research environments.

While Specific Informed Consent has been the established standard for obtaining consent for medical research for many years, it does not appear suitable for large-scale biobank and health data research. Thus, alternative forms of consent have been suggested, based on a variety of ethical background assumptions. This article identifies five main ethical perspectives at stake. Even though Tiered Consent, Dynamic Consent and Meta Consent are designed to the demands of the self-determination perspective as well as the perspective of research as a public good, they are still also criticized from both perspectives. In addition, criticisms based on concerns of justice, participation and democratic deliberation, and relational concerns have been levelled at each of the models. As all of these perspectives have valid points to make, the task at hand lies in balancing these ethical perspectives. What constitutes an adequate balancing depends on contextual factors. These factors include digital infrastructure and digital literacy, data safety regulation, good scientific and clinical practice, transparent debates on ethically relevant features of research, social inequalities, anti-discrimination laws and practices, trust in health care institutions and recognition of patient preferences, and consensus on unethical research. We argue that the role of context in determining acceptable models of consent puts the ethical importance of models of consent into perspective. Since altering contextual factors can help to live up to the ethical concerns at stake in debates about models of consent, opting for such a shift of focus comes without ethical loss.

Allocating scarce intensive care resources during the COVID-19 pandemic: practical challenges to theoretical frameworks.

The COVID-19 pandemic strained health-care systems throughout the world. For some, available medical resources could not meet the increased demand and rationing was ultimately required. Hospitals and governments often sought to establish triage committees to assist with allocation decisions. However, for institutions operating under crisis standards of care (during times when standards of care must be substantially lowered in the setting of crisis), relying on these committees for rationing decisions was impractical-circumstances were changing too rapidly, occurring in too many diverse locations within hospitals, and the available information for decision making was notably scarce. Furthermore, a utilitarian approach to decision making based on an analysis of outcomes is problematic due to uncertainty regarding outcomes of different therapeutic options. We propose that triage committees could be involved in providing policies and guidance for clinicians to help ensure equity in the application of rationing under crisis standards of care. An approach guided by egalitarian principles, integrated with utilitarian principles, can support physicians at the bedside when they must ration scarce resources.

Do we have a moral obligation to synthesize organisms to increase biodiversity? On kinship, awe, and the value of life's diversity.

Synthetic biology can be understood as expanding the abilities and aspirations of genetic engineering. Nonetheless, whereas genetic engineering has been subject to criticism due to its endangering biodiversity, synthetic biology may actually appear to prove advantageous for biodiversity. After all, one might claim, synthesizing novel forms of life increases the numbers of species present in nature and thus ought to be ethically recommended. Two perspectives on how to spell out the conception of intrinsic value of biodiversity are examined in order to assess this line of thought. At the cost of introducing two separate capacities of human knowledge acquisition, the 'admiration stance' turns out to reject outright the assumption of a synthetic species' intrinsic value and of an imperative to create novel species. The 'kinship stance' by contrast does ascribe value to both synthetic and natural species and organisms. Nonetheless, while from this perspective creating novel species may become an ethical demand under certain conditions, it favours changing organisms by getting in contact with them rather than synthesizing them. It is concluded that neither the admiration nor the kinship stance warrants a supposed general moral obligation to create novel species to increase biodiversity.

Noninvasive assessment of cardiac output using thoracic electrical bioimpedance in hemodynamically stable and unstable patients after cardiac surgery: a comparison with pulmonary artery thermodilution.

OBJECTIVE: To compare noninvasive cardiac output (CO)measurement obtained with a new thoracic electrical bioimpedance (TEB) device, using a proprietary modification of the impedance equation, with invasive measurement obtained via pulmonary artery thermodilution. DESIGN: Prospective, observational study. SETTING: Surgical intensive care unit (ICU) of a university-affiliated community hospital. PATIENTS AND PARTICIPANTS: Seventy-four adult patients undergoing elective cardiac surgery with routine pulmonary artery catheter placement. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Simultaneous paired CO and cardiac index (CI) measurements by TEB and thermodilution were obtained in mechanically ventilated patients upon admission to the ICU. For analysis of CI data the patients were subdivided into a hemodynamically stable group and a hemodynamically unstable group. The groups were analyzed using linear regression and tests of bias and precision. We found a significant correlation between thermodilution and TEB (r = 0.83; n < 0.001), accompanied by a bias of -0.01 l/min/m(2) and a precision of +/-0.57 l/min/m(2) for all CI data pairs. Correlation, bias, and precision were not influenced by stratification of the data. The correlation coefficient, bias, and precision for CI were 0.86 (n< 0.001), 0.03 l/min/m(2), and +/-0.47 l/min/m(2) in hemodynamically stable patients and 0.79 (n< 0.001), 0.06 l/min/m(2), and +/-0.68 l/min/m(2) in hemodynamically unstable patients. CONCLUSIONS: Our results demonstrate a close correlation and clinically acceptable agreement and precision between CO measurements obtained with impedance cardiography using a new algorithm to calculate CO from variations in TEB, and those obtained with the clinical standard of care, pulmonary artery thermodilution, in hemodynamically stable and unstable patients after cardiac surgery.

New light on intravascular volume replacement regimens: what did we learn from the past three years?

UNLABELLED: Definition of the "ideal" intravascular fluid volume replacement strategy still remains a critical problem. This article analyzes studies on volume replacement by using a MEDLINE search of the past 3 years (from January 1, 2000, to December 12, 2002). Forty original studies in humans with a total of 2454 subjects were identified. Five studies were performed in volunteers (n = 113); the other 35 studies (n = 2341) were performed in a variety of patients (e.g., cardiac surgery, trauma patients, children, and intensive care unit patients). The influence of different volume replacement regimens on coagulation was one of the major topics of interest (16 studies with 1183 subjects), and other studies focused on metabolic state, alterations in macro- and microcirculation, volume distribution, and organ function (e.g., kidney function and splanchnic perfusion). Among all synthetic colloids, hydroxyethyl starch (HES) was the solution most often studied. Two new HES preparations have been approved (Hextend), a balanced hetastarch solution, and a new third-generation HES [130/0.4]). Only two studies used albumin, and no superiority of albumin was found over less expensive synthetic colloids. In almost all studies, the outcome either was no end-point or was not reported. Volume replacement has often been hitherto based on dogma and personal beliefs. Future well performed studies in this area will hopefully help to shed new light on the ideal volume replacement strategy. IMPLICATIONS: By using a MEDLINE search covering the last 3 yr, the present knowledge on volume replacement regimens was analyzed. Forty studies in humans were identified. New hydroxyethyl starch preparations have shed light on this topic, whereas no additional data supporting the use of albumin have been presented.

Bispectral index-guided anesthesia in patients undergoing aortocoronary bypass grafting.

In this prospective, randomized study, we compared hemodynamics, oxygenation, possible intraoperative awareness, and costs in 62 patients undergoing first-time elective coronary artery bypass grafting at 2 different levels of anesthesia. Depth of anesthesia was assessed with bispectral index (BIS). All patients were anesthetized with sufentanil/midazolam. The dosage of sufentanil/midazolam was adjusted to achieve a BIS level of 45-55 in 32 patients (Group BIS 50), whereas in 30 patients a BIS level of 35-45 was intended (Group BIS 40). Data were obtained at six different time points before, during, and after surgery. All patients were asked about possible intraoperative awareness on the third postoperative day. There were no significant differences of any hemodynamic or oxygenation variables at any time between the two groups. BIS 40 patients received significantly (P < 0.05) more sufentanil (BIS 40, 888 +/- 211 microg; BIS 50, 514 +/- 99 microg) and midazolam (BIS 40, 22.4 +/- 5.6 mg; BIS 50, 16.6 +/- 3.7 mg) than BIS 50 patients. The reduction in anesthetic drugs used saved euro;13.78/US$12.54 per patient (P < 0.05) in Group BIS 50, but one BIS electrode caused additional costs of 19.95 Euros/18.15 US dollars. Time to extubation was not significantly prolonged in Group BIS 40 (BIS 40, 14.3 +/- 4.6 h; BIS 50, 11.8 +/- 3.8 h). There was no explicit memory during anesthesia in either group. BIS-guided reduction of anesthetic medication saved costs and did not increase the risk of intraoperative awareness. However, total costs were increased by monitoring BIS, because of the BIS electrodes.

Bispectral index in patients with target-controlled or manually-controlled infusion of propofol.

UNLABELLED: In this prospective, randomized study we compared bispectral index (BIS), hemodynamics, time to extubation, and the costs of target-controlled infusion (TCI) and manually-controlled infusion (MCI) of propofol. Forty patients undergoing first-time implantation of a cardioverter-defibrillator were included. Anesthesia was performed with remifentanil (0.2-0.3 micro g. kg(-1). min(-1)) and propofol. Propofol was used as TCI (plasma target concentration, 2.5-3.5 micro g/mL; n = 20) or MCI (3.0-4.0 mg. kg(-1). h(-1); n = 20). BIS, heart rate, and arterial blood pressure were measured at six data points: T1, before anesthesia; T2, after intubation; T3, after skin incision; T4, after first defibrillation; T5, after third defibrillation; and T6, after extubation. There were no significant hemodynamic differences between the two groups. BIS was significantly lower at T3 and T4 in the TCI group than in the MCI group. The mean dose of propofol was larger in TCI patients (5.8 +/- 1.4 mg. kg(-1). h(-1)) than in the MCI patients (3.7 +/- 0.6 mg. kg(-1). h(-1)) (P < 0.05), whereas doses of remifentanil did not differ. Time to extubation did not differ between the two groups (TCI, 13.7 +/- 5.3 min; MCI, 12.3 +/- 3.5 min). One patient in the MCI group had signs of intraoperative awareness without explicit memory after first defibrillation (BIS before shock, 49; after shock, 83). Costs were significantly less in the MCI group (34.83 US dollars) than in the TCI group (39.73 US dollars). BIS failed to predict the adequacy of anesthesia for the next painful stimulus. IMPLICATIONS: In this prospective, randomized study, bispectral index (BIS), hemodynamics, time to extubation, and costs of target-controlled infusion (TCI) and manually-controlled infusion of propofol were compared. TCI increased the amount of propofol used. BIS failed to predict the adequacy of anesthesia for the next painful stimulus.

Pharmacoeconomic considerations in anaesthetic use.

Healthcare costs are rising in all areas of medicine, especially in high technology specialities such as anaesthesia. Therefore, cost containment and reduction have become major goals in many hospitals and anaesthesia departments. One area that has received substantial attention is the cost of pharmaceutical products, in particular the cost of newer, shorter-acting inhaled and intravenous anaesthetics, analgesics and neuromuscular blocking agents. Numerous pharmacoeconomic studies have been published on the theoretical analysis of anaesthetic drug costs and the potential benefit of various anaesthesia techniques. However, the results are not conclusive and anaesthesia departments continue to seek ways to reduce costs. In this review, we intend to discuss cost terminology, common areas of cost containment in anaesthesia and the relationship of anaesthesia care costs to total perioperative costs.