Individually optimized hemodynamic therapy reduces complications and length of stay in the intensive care unit: a prospective, randomized controlled trial.

BACKGROUND: The authors hypothesized that goal-directed hemodynamic therapy, based on the combination of functional and volumetric hemodynamic parameters, improves outcome in patients with cardiac surgery. Therefore, a therapy guided by stroke volume variation, individually optimized global end-diastolic volume index, cardiac index, and mean arterial pressure was compared with an algorithm based on mean arterial pressure and central venous pressure. METHODS: This prospective, controlled, parallel-arm, open-label trial randomized 100 coronary artery bypass grafting and/or aortic valve replacement patients to a study group (SG; n = 50) or a control group (CG; n = 50). In the SG, hemodynamic therapy was guided by stroke volume variation, optimized global end-diastolic volume index, mean arterial pressure, and cardiac index. Optimized global end-diastolic volume index was defined before and after weaning from cardiopulmonary bypass and at intensive care unit (ICU) admission. Mean arterial pressure and central venous pressure served as hemodynamic goals in the CG. Therapy was started immediately after induction of anesthesia and continued until ICU discharge criteria, serving as primary outcome parameter, were fulfilled. RESULTS: Intraoperative need for norepinephrine was decreased in the SG with a mean (±SD) of 9.0 ± 7.6 versus 14.9 ± 11.1 µg/kg (P = 0.002). Postoperative complications (SG, 40 vs. CG, 63; P = 0.004), time to reach ICU discharge criteria (SG, 15 ± 6 h; CG, 24 ± 29 h; P < 0.001), and length of ICU stay (SG, 42 ± 19 h; CG, 62 ± 58 h; P = 0.018) were reduced in the SG. CONCLUSION: Early goal-directed hemodynamic therapy based on cardiac index, stroke volume variation, and optimized global end-diastolic volume index reduces complications and length of ICU stay after cardiac surgery.

The wolf is crying in the operating room: patient monitor and anesthesia workstation alarming patterns during cardiac surgery.

BACKGROUND: Vital sign monitors and ventilator/anesthesia workstations are equipped with multiple alarms to improve patient safety. A high number of false alarms can lead to a "crying wolf" phenomenon with consecutively ignored critical situations. Systematic data on alarm patterns and density in the perioperative phase are missing. Our objective of this study was to characterize the patterns of alarming of a commercially available patient monitor and a ventilator/anesthesia workstation during elective cardiac surgery. METHODS: We performed a prospective, observational study in 25 consecutive elective cardiac surgery patients. In all patients, identically fixed alarm settings were used. All incoming patient data and all alarms from the patient monitor and the anesthetic workstation were digitally recorded. Additionally, the anesthesia workplace was videotaped from 2 different angles to allow retrospective annotation and correlation of alarms with the clinical situation and assessment of the anesthesiologists' reaction to the alarms. RESULTS: Of the 8975 alarms, 7556 were hemodynamic alarms and 1419 were ventilatory alarms. For each procedure, 359 ± 158 alarms were recorded, representing a mean density of alarms of 1.2/minute. CONCLUSION: Approximately 80% of the total 8975 alarms had no therapeutic consequences. Implementation of procedure-specific settings and optimization in artifact and technical alarm detection could improve patient surveillance and safety.