A Fate Worse Than Death: Prognostication of Devastating Brain Injury.

OBJECTIVES: To describe the sources of uncertainty in prognosticating devastating brain injury, the role of the intensivist in prognostication, and ethical considerations in prognosticating devastating brain injury in the ICU. DATA SOURCES: A PubMed literature review was performed. STUDY SELECTION: Articles relevant to prognosis in intracerebral hemorrhage, acute ischemic stroke, traumatic brain injury, subarachnoid hemorrhage, and postcardiac arrest anoxic encephalopathy were selected. DATA EXTRACTION: Data regarding definition and prognosis of devastating brain injury were extracted. Themes related to how clinicians perform prognostication and their accuracy were reviewed and extracted. DATA SYNTHESIS: Although there are differences in pathophysiology and therefore prognosis in the various etiologies of devastating brain injury, some common themes emerge. Physicians tend to have fairly good prognostic accuracy, especially in severe cases with poor prognosis. Full supportive care is recommended for at least 72 hours from initial presentation to maximize the potential for recovery and minimize secondary injury. However, physician approaches to the timing of and recommendations for withdrawal of life-sustaining therapy have a significant impact on mortality from devastating brain injury. CONCLUSIONS: Intensivists should consider the modern literature describing prognosis for devastating brain injury and provide appropriate time for patient recovery and for discussions with the patient's surrogates. Surrogates wish to have a prognosis enumerated even when uncertainty exists. These discussions must be handled with care and include admission of uncertainty when it exists. Respect for patient autonomy remains paramount, although physicians are not required to provide inappropriate medical therapies.

Platelet Count Trends and Prevalence of Heparin-Induced Thrombocytopenia in a Cohort of Extracorporeal Membrane Oxygenator Patients.

OBJECTIVES: To assess the prevalence of heparin-induced thrombocytopenia and to study platelet count trends potentially suggestive of heparin-induced thrombocytopenia in a population of extracorporeal membrane oxygenator patients. DESIGN: Retrospective cohort study. SETTING: A total of 926-bed teaching hospital. PATIENTS: Extracorporeal membrane oxygenator patients who survived longer than 48 hours from extracorporeal membrane oxygenator initiation between January 1, 2009, and December 31, 2013. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Demographic and clinical data were collected prospectively on all extracorporeal membrane oxygenator patients. Heparin-induced thrombocytopenia testing results and platelet count variables were obtained from the electronic medical record. We used our institutional algorithm to interpret the results of heparin-induced thrombocytopenia testing. Ninety-six extracorporeal membrane oxygenator patients met the inclusion criteria. Eight patients met the algorithm criteria for heparin-induced thrombocytopenia diagnosis and seven of those had documented thromboembolic event while on extracorporeal membrane oxygenator (prevalence of heparin-induced thrombocytopenia and heparin-induced thrombocytopenia related thrombosis, 8.3 and 7.3, respectively). Heparin-induced thrombocytopenia positive patients were younger; all underwent venoarterial extracorporeal membrane oxygenator; spent more hours on extracorporeal membrane oxygenator; had significantly higher heparin-induced thrombocytopenia enzyme-linked immunosorbent assays optical density; had a higher prevalence of thromboembolic events and reached platelet count nadir later. There was no difference in mortality between heparin-induced thrombocytopenia positive and negative patients. Comparison of platelet count trends revealed that there was no statistically significant difference between the predefined study groups. CONCLUSIONS: Prevalence of heparin-induced thrombocytopenia and heparin-induced thrombocytopenia-related thrombosis among extracorporeal membrane oxygenator patients at our institution is relatively high. Using platelet count trends to guide decision to test for heparin-induced thrombocytopenia is not an optimal strategy in extracorporeal membrane oxygenator patients. Without a validated pretest probability clinical score, serosurveillance in a defined high-risk group of extracorporeal membrane oxygenator patients may be needed.

Left ventricular assist device management in the ICU.

OBJECTIVES: To review left ventricular assist device physiology, initial postoperative management, common complications, trouble shooting and management of hypotension, and other common ICU problems. DATA SOURCE: Narrative review of relevant medical literature. DATA SYNTHESIS: Left ventricular assist devices prolong the lives of patients with end-stage heart failure, and their use is increasing. Continuous-flow left ventricular assist devices have replaced first-generation pulsatile devices. These patients present unique management concerns. In the immediate postimplant period, care must be taken to support the unassisted right ventricle. Invasive monitors for blood pressure, pulmonary artery catheterization, and echocardiography are essential to optimize left ventricular assist device settings and cardiac performance. Anticoagulation is necessary to prevent devastating thrombotic and embolic complications, but bleeding is a major source of morbidity due to inherent bleeding diatheses and prescribed anticoagulants. Infection of the device can be life threatening, and all infections must be aggressively treated to avoid seeding the device. Patients are at risk of ventricular arrhythmias because of their underlying disease, as well as the placement and position of the inflow cannula. Aortic valve stenosis and insufficiency develop over time and can lead to thrombosis or heart failure. Cardiopulmonary resuscitation with chest compressions must be performed with care or not at all due to risk of dislodging the device. CONCLUSION: Intensivists are increasingly likely to encounter patients requiring mechanical circulatory support with left ventricular assist devices at various points in the trajectory of their disease, from the immediate postimplant period to subsequent admissions for complications, and at end of life. A basic understanding of left ventricular assist device physiology is essential to the safe and effective care of these patients.

Pharmacokinetics of liposomal amphotericin B in pleural fluid.

We report the penetration of liposomal amphotericin B into the pleural fluid of a patient with pulmonary zygomycosis and empyema. The ratio of area under the concentration-versus-time curve in pleural fluid (AUC(pleural fluid)) to that in serum (AUC(serum)) for liposomal amphotericin B over 24 h was 9.4%, with pleural fluid concentrations of 2.12 to 4.91 microg/ml. Given the relatively low level of intrapleural penetration of liposomal amphotericin B, chest tube drainage may be warranted for successful treatment of zygomycotic empyema.