Journal of clinical monitoring and computing
-
J Clin Monit Comput · Apr 2017
Observational StudyUtility of stroke volume variation measured using non-invasive bioreactance as a predictor of fluid responsiveness in the prone position.
The aim of this prospective study was to evaluate the usefulness of stroke volume variation (SVV) derived from NICOM® to predict fluid responsiveness in the prone position. Forty adult patients undergoing spinal surgery in the prone position were included in this study. We measured SVV from NICOM® (SVVNICOM) and FloTrac™/Vigileo™ systems (SVVVigileo), and pulse pressure variation (PPV) using automatic (PPVauto) and manual (PPVmanual) calculations at four time points including supine and prone positions, and before and after fluid loading of 6 ml kg-1 colloid solution. ⋯ The optimal cut-off values were 12 % for SVVNICOM, SVVVigileo, and PPVauto, and 10 % for PPVmanual. SVV from NICOM® successfully predicts fluid responsiveness during surgery in the prone position. This totally non-invasive technique for assessing individual functional intravenous volume status would be useful in a wide range of surgeries performed in the prone position.
-
J Clin Monit Comput · Apr 2017
FLOW-i ventilator performance in the presence of a circle system leak.
Recently, the FLOW-i anaesthesia ventilator was developed based on the SERVO-i intensive care ventilator. The aim of this study was to test the FLOW-i's tidal volume delivery in the presence of a leak in the breathing circuit. We ventilated a test lung model in volume-, pressure-, and pressure-regulated volume-controlled modes (VC, PC, and PRVC, respectively) with a FLOW-i. ⋯ Interestingly, VT did not differ appreciably from 6 to 0.3 L/min of fresh air flow among the 3 ventilatory modes. In the absence of leakage, peak inspiratory pressures were similar, while they were 35-45 % smaller in PRVC and VC than in PC mode in the presence of leaks. In conclusion, FLOW-i maintained VT (down to fresh gas flows of 0.3 L/min) to 90 % of its preset value in PC mode, which was 4-5 times greater than in VC or PRVC modes.
-
J Clin Monit Comput · Apr 2017
Optimal level of the reference transducer for central venous pressure and pulmonary artery occlusion pressure monitoring in supine, prone, and sitting position.
To guarantee accurate measurement of central venous pressure (CVP) or pulmonary artery occlusion pressure (PAOP), proper positioning of a reference transducer is a prerequisite. We investigated ideal transducer levels in supine, prone, and sitting position in adults. Chest computed tomography images of 113 patients, taken in supine or prone position were reviewed. ⋯ The ratio of the most cephalad blood level of RA and LA to the sternal length was 0.70 ± 0.10 and 0.68 ± 0.09 from the mid-sternoclavicular joint in sitting position, which corresponded to the upper border of 4th rib. Optimal CVP transducer levels are at four-fifths of the AP diameter of thorax in supine position, at a half of that in prone position, and at upper border of the 4th sternochondral joint in sitting position. PAOP transducer levels are similar in prone and sitting position, except for supine position which is at three-fifths of the AP diameter of thorax.
-
J Clin Monit Comput · Apr 2017
ReviewJournal of clinical monitoring and computing 2016 end of year summary: monitoring cerebral oxygenation and autoregulation.
In the perioperative and critical care setting, monitoring of cerebral oxygenation (ScO2) and cerebral autoregulation enjoy increasing popularity in recent years, particularly in patients undergoing cardiac surgery. Monitoring ScO2 is based on near infrared spectroscopy, and attempts to early detect cerebral hypoperfusion and thereby prevent cerebral dysfunction and postoperative neurologic complications. ⋯ As a consequence, intraoperative hypotension will be poorly tolerated, and might cause ischemic events and postoperative neurological complications. This article summarizes research investigating technologies for the assessment of ScO2 and cerebral autoregulation published in the Journal of Clinical Monitoring and Computing in 2016.
-
J Clin Monit Comput · Apr 2017
Comparative StudyComparison of stroke volumes assessed by three-dimensional echocardiography and transpulmonary thermodilution in a pediatric animal model.
To compare stroke volumes (SV) in small hearts assessed by real-time three-dimensional echocardiography (3DE) with SV measured by transpulmonary thermodilution (TPTD) and continuous pulse contour analysis (PC) under various hemodynamic conditions. In thirteen anesthetized piglets (range 3.6-7.1 kg) SV were measured by 3DE, TPTD and PC at baseline and during phenylephrine and esmolol administration. 3DE and TPTD measurements were done successively while SV calculated by PC was documented at the time of 3DE. 3DE and TPTD showed a good correlation (r2 = 0.74) and a bias of -1.3 ml (limits of agreement -4.1 to 1.5 ml). While TPTD measured higher SV than 3DE, both methods tracked SV changes with a concordance rate of 91 %. ⋯ PC measured SV with a higher variance and mean difference compared to 3DE. In an experimental setting 3DE has the possibility to offer non-invasive assessments of ventricular volumes volume changes. To determine whether 3DE could be used for SV assessment in a clinical routine our results need confirmation in a clinical setting.