Natriuretic Equation to Predict Loop Diuretic Response in Patients With Heart Failure.

BACKGROUND: Most acute decompensated heart failure admissions are driven by congestion. However, residual congestion is common and often driven by the lack of reliable tools to titrate diuretic therapy. The authors previously developed a natriuretic response prediction equation (NRPE), which predicts sodium output using a spot urine sample collected 2 h after loop diuretic administration. OBJECTIVES: The purpose of this study was to validate the NRPE and describe proof-of-concept that the NRPE can be used to guide diuretic therapy. METHODS: Two cohorts were assembled: 1) the Diagnosing and Targeting Mechanisms of Diuretic Resistance (MDR) cohort was used to validate the NRPE to predict 6-h sodium output after a loop diuretic, which was defined as poor (<50 mmol), suboptimal (<100 mmol), or excellent (>150 mmol); and 2) the Yale Diuretic Pathway (YDP) cohort, which used the NRPE to guide loop diuretic titration via a nurse-driven automated protocol. RESULTS: Evaluating 638 loop diuretic administrations, the NRPE showed excellent discrimination with areas under the curve ≥0.90 to predict poor, suboptimal, and excellent natriuretic response, and outperformed clinically obtained net fluid loss (p < 0.05 for all cutpoints). In the YDP cohort (n = 161) using the NRPE to direct therapy mean daily urine output (1.8 ± 0.9 l vs. 3.0 ± 0.8 l), net fluid output (-1.1 ± 0.9 l vs. -2.1 ± 0.9 l), and weight loss (-0.3 ± 0.3 kg vs. -2.5 ± 0.3 kg) improved substantially following initiation of the YDP (p < 0.001 for all pre-post comparisons). CONCLUSIONS: Natriuretic response can be rapidly and accurately predicted by the NRPE, and this information can be used to guide diuretic therapy during acute decompensated heart failure. Additional study of diuresis guided by the NRPE is warranted.

Safety and Patients' Response to Ambulation With a Pulmonary Artery Catheter in the Cardiac Intensive Care Unit.

BACKGROUND: Early mobilization of patients in the intensive care unit can be beneficial, but evidence is insufficient to indicate whether allowing patients with an indwelling pulmonary artery catheter to walk is safe. OBJECTIVE: To describe the physiological and emotional responses to ambulation in patients with heart failure and a pulmonary artery catheter. METHODS: This prospective, descriptive study included 19 patients with heart failure monitored with a pulmonary artery catheter in a cardiac intensive care unit. Each patient, accompanied by a nurse, walked with continuous observation of heart rate and rhythm and pulmonary artery tracing on a transport monitor. Pulmonary artery catheter position and waveform, arrhythmias, and perceived levels of exertion and fatigue were recorded before and after each walk. The distance ambulated was documented. One to 3 times per week, nurses administered a questionnaire addressing patients' sense of well-being. RESULTS: The 19 patients had 303 walks (range, 1-68; median, 7). During 7 patient walks (2.4%), catheter migration of 1 to 5 cm occurred, but no arrhythmias or waveform changes were observed. Changes in exertion and fatigue were significant (P < .001, paired t test), but levels of both were minimal after walking. Patients expressed physical and emotional benefits of walking. CONCLUSIONS: This study provides preliminary evidence that for hemodynamically stable patients with heart failure, ambulating with a pulmonary artery catheter is safe and enhances their sense of well-being. The presence of an indwelling pulmonary artery catheter should not preclude walking.

Detecting myocardial ischemia with continuous ST-segment monitoring: two case studies.

Continuous ST-segment ischemia monitoring is recommended for patients at significant risk for myocardial ischemia that, if sustained, may result in acute myocardial infarction or extension of a myocardial infarction. It is especially useful for patients who do not perceive or cannot communicate symptoms of ischemia. We report 2 case studies of young women with acute coronary syndrome who benefited from continuous ST-segment monitoring. One patient was critically ill and unresponsive, and one patient had atypical symptoms and some difficulty communicating clearly.

Optimal management of shivering during therapeutic hypothermia after cardiac arrest.

Both pharmacological and nonpharmacological methods are used to control shivering in therapeutic hypothermia. An evidence-based protocol based on the most current research has been developed for the management of shivering during therapeutic hypothermia. Meperidine is the drug of choice and provides the greatest reduction in the shivering threshold. Other effective pharmacological agents recommended for reducing the threshold include dexmedetomidine, midazolam, fentanyl, and magnesium sulfate. In addition, skin counterwarming techniques, such as use of an air-circulating blanket, are effective nonpharmacological methods for reducing shivering when used in conjunction with medication. As a last resort, neuromuscular blocking agents are considered appropriate therapy for management of refractory shivering.

Continuous ST-segment monitoring: nurses' attitudes, practices, and quality of patient care.

BACKGROUND: Continuous ischemia monitoring helps identify patients with acute, but often silent, myocardial ischemia. Evidence suggests nurses do not activate ischemia monitoring because they think it is difficult to use. ST-Map software incorporates graphic displays to make monitoring of ongoing ischemia easier. OBJECTIVES: To determine if nurses' use of and attitude toward ischemia monitoring and the quality of patient care improve with use of ST-Map. METHODS: The study included 61 nurses and 202 patients with acute coronary syndrome in a cardiac intensive care unit. Baseline data on nurses' use of and attitude toward ischemia monitoring and quality of care were obtained. Education was then provided and ST-Map software was installed on all monitors. Follow-up data were obtained 4 months later. RESULTS: The percentage of nurses who had ever used ischemia monitoring was 13% before ST Map and 90% afterward (P < .001). The most common reason for not using ischemia monitoring before ST Map was inadequate knowledge (62%). The most common reason for liking ischemia monitoring after ST Map was knowing when a patient has ischemia (80%). Time to acquisition of a 12-lead electrocardiogram in response to symptoms or ST-segment changes was 5 to 15 minutes before ST Map and always less than 5 minutes afterward (P < .001). Time to return to the catheterization laboratory did not differ before and after ST Map. CONCLUSIONS: ST Map was associated with more frequent use of ischemia monitoring, improved attitudes of nurses toward ischemia monitoring, and shorter time to obtaining 12-lead electrocardiograms.

Prolonged mechanical ventilation and tracheostomy in the elderly.

Mechanical ventilation is a life-sustaining technology used with increasing frequency in the elderly population. Prolonged mechanical ventilation is associated with high morbidity, mortality, and poor functional status. Care of these complex patients requires a coordinated multidisciplinary approach to optimize outcome. To minimize mortality and morbidity and contain health care costs, it is essential to identify patients at high risk for prolonged ventilation and to implement early interventions to curtail functional decline. In this article, the incidence and outcome of prolonged mechanical ventilation is reviewed, along with interventions to promote recovery. In particular, the role of tracheostomy timing and placement is discussed.