Faculty Bibliography

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.

INTRODUCTION: Acute circulatory dysfunction in patients with sepsis can evolve rapidly into a progressive stage associated with high mortality. Early recognition and adequate resuscitation could improve outcome. However, since the spectrum of clinical presentation is quite variable, signs of hypoperfusion are frequently unrecognized in patients just admitted to the emergency department (ED). Hyperlactatemia is considered a key parameter to disclose tissue hypoxia but it is not universally available and getting timely results can be challenging in low resource settings. In addition, non-hypoxic sources can be involved in hyperlactatemia, and a misinterpretation could lead to over-resuscitation in an unknown number of cases. Capillary refill time (CRT) is a marker of peripheral perfusion that worsens during circulatory failure. An abnormal CRT in septic shock patients after ICU-based resuscitation has been associated with poor outcome. The aim of this study was to determine the prevalence of abnormal CRT in patients with sepsis-related hyperlactatemia in the early phase after ED admission, and its relationship with outcome. METHODS: We performed a prospective observational study. Septic patients with hyperlactemia at ED admission subjected to an initial fluid resuscitation (FR) were included. CRT and other parameters were assessed before and after FR. CRT-normal or CRT-abnormal subgroups were defined according to the status of CRT following initial FR, and major outcomes were registered. RESULTS: Ninety-five hyperlactatemic septic patients were included. Thirty-one percent had abnormal CRT at ED arrival. After FR, 87 patients exhibited normal CRT, and 8 an abnormal one. Patients with abnormal CRT had an increased risk of adverse outcomes (88% vs. 20% p<0.001; RR 4.4 [2.7-7.4]), and hospital mortality (63% vs. 9% p<0.001; RR 6.7 [2.9-16]) as compared to those with normal CRT after FR. Specifically, CRT-normal patients required less frequently mechanical ventilation, renal replacement therapy, and ICU admission, and exhibited a lower hospital mortality. CONCLUSIONS: Hyperlactatemic sepsis patients with abnormal CRT after initial fluid resuscitation exhibit higher mortality and worse clinical outcomes than patients with normal CRT.

BACKGROUND: Wernicke encephalopathy can have different clinical outcomes. Although infections may precipitate the encephalopathy itself, it is unknown whether infections also modify the long-term outcome in patients developing Korsakoff syndrome. OBJECTIVE: To determine whether markers of infection, such as white blood cell (WBC) counts and absolute neutrophil counts in the Wernicke phase, are associated with cognitive outcomes in the end-stage Korsakoff syndrome. METHOD: Retrospective, descriptive study of patients admitted to Slingedael Korsakoff Center, Rotterdam, The Netherlands. Hospital discharge letters of patients with Wernicke encephalopathy were searched for relevant data on infections present upon hospital admission. Patients were selected for further analysis if data were available on WBC counts in the Wernicke phase and at least 1 of 6 predefined neuropsychological tests on follow-up. RESULTS: Infections were reported in 35 of 68 patients during the acute phase of Wernicke-Korsakoff syndrome-meningitis (1), pneumonia (14), urinary tract infections (9), acute abdominal infections (4), sepsis (5) empyema, (1) and infection "of unknown origin" (4). The neuropsychological test results showed significant lower scores on the Cambridge Cognitive Examination nonmemory section with increasing white blood cell counts (Spearman rank correlation, rho = -0.34; 95% CI: -0.57 to -0.06; 44 patients) and on the "key search test" of the behavioral assessment of the dysexecutive syndrome with increasing absolute neutrophil counts (rho= -0.85; 95% CI: -0.97 to -0.42; 9 patients). CONCLUSIONS: Infections may be the presenting manifestation of thiamine deficiency. Patients with Wernicke-Korsakoff syndrome who suffered from an infection during the acute phase are at risk of worse neuropsychological outcomes on follow-up.

PURPOSE: To correlate clinical indicators of peripheral perfusion with visceral organ vascular tone in 30 septic shock patients. MATERIALS AND METHODS: In a prospective pilot study, capillary refill time, the Mottling score, and peripheral temperature were determined within 24, 48, and 72 hours after intensive care unit admission. Simultaneously, pulsatility indices in the liver, spleen, kidneys, and intestines were measured by Doppler ultrasonography. Correlation analyses were calculated, applying an adjusted significance level (P< .0125) to correct for multiple testing. RESULTS: Significant relationships were observed between the pulsatility index of selected organs and the capillary refill time (intestines: r= 0.325, P= .007), and the Mottling score (kidneys: r= 0.396, P= .006), but not peripheral temperature (all r< 0.14, P> .05). An association over time was observed for the capillary refill time and pulsatility index of the liver (P= .04) and intestines (P= .03) as well as for the Mottling score and the kidneys' pulsatility index (P= .03), but not for peripheral temperature and any visceral organs' pulsatility index. CONCLUSIONS: Capillary refill time and skin mottling may be correlated with the pulsatility index, a sonographic surrogate of vascular tone, of visceral organs in early septic shock.

BACKGROUND: Persistent hyperlactatemia during septic shock is multifactorial. Hypoperfusion-related anaerobic production and adrenergic-driven aerobic generation together with impaired lactate clearance have been implicated. An excessive adrenergic response could contribute to persistent hyperlactatemia and adrenergic modulation might be beneficial. We assessed the effects of dexmedetomidine and esmolol on hemodynamics, lactate generation, and exogenous lactate clearance during endotoxin-induced septic shock. METHODS: Eighteen anesthetized and mechanically ventilated sheep were subjected to a multimodal hemodynamic/perfusion assessment including hepatic and portal vein catheterizations, total hepatic blood flow, and muscle microdialysis. After monitoring, all received a bolus and continuous infusion of endotoxin. After 1 h they were volume resuscitated, and then randomized to endotoxin-control, endotoxin-dexmedetomidine (sequential doses of 0.5 and 1.0 mug/k/h) or endotoxin-esmolol (titrated to decrease basal heart rate by 20 %) groups. Samples were taken at four time points, and exogenous lactate clearance using an intravenous administration of sodium L-lactate (1 mmol/kg) was performed at the end of the experiments. RESULTS: Dexmedetomidine and esmolol were hemodynamically well tolerated. The dexmedetomidine group exhibited lower epinephrine levels, but no difference in muscle lactate. Despite progressive hypotension in all groups, both dexmedetomidine and esmolol were associated with lower arterial and portal vein lactate levels. Exogenous lactate clearance was significantly higher in the dexmedetomidine and esmolol groups. CONCLUSIONS: Dexmedetomidine and esmolol were associated with lower arterial and portal lactate levels, and less impairment of exogenous lactate clearance in a model of septic shock. The use of dexmedetomidine and esmolol appears to be associated with beneficial effects on gut lactate generation and lactate clearance and exhibits no negative impact on systemic hemodynamics.