Journal of clinical monitoring and computing
-
J Clin Monit Comput · Jun 2019
Change in staff anesthesiologists' opinions of an Anesthesia Information Management System (AIMS).
Following introduction of an Anesthesia Information Management System (AIMS) at a tertiary care, academic health sciences centre, a quality assurance initiative was conducted to assess staff opinions of the AIMS using a previously published, anonymous survey tool at 1 and 5 years following AIMS introduction. At 5 years compared to 1 year after implementation of AIMS, the majority (18 of 24, 75%) of responses to the survey questions had a statistically significant change (P < 0.05) in the proportion of respondents favoring AIMS compared to the 1 year survey. Domains noted to be more favorable 5 years compared to 1 year after AIMS introduction included patient safety in the Operating Rooms and Post-Anesthesia Care Unit, quality of handover and overall documentation, and communication amongst healthcare workers. The ideal time period at which to assess AIMS after introduction is not clear.
-
J Clin Monit Comput · Jun 2019
A motor evoked potential trending system may discriminate outcome: retrospective application with three cases.
This report presents a method for tracking Motor Evoked Potential (MEP) amplitudes over the course of a case using a moving least squares linear regression (LSMAs). During a case, newly obtained MEP amplitudes are compared to those predicted by a just previous linear regression (least squares moving average or LSMA). When detected by this comparison, a set criterion amplitude loss will then trigger linear regression of ensuing MEP amplitudes on an expanding step function which tracks the persistence of the amplitude loss for the remainder of the case. ⋯ In the third case the tracking method again successfully triggered a predictive R-Square despite the limited number of pre-event trials. The R-Square value of the expanding step function regression appears to have discriminative capability with regard to new post-op deficit. Given the importance of the intra-operative MEP for monitoring motor functioning and the high degree of variability that can affect it, the development of new quantitative, statistical methods to detect real from apparent MEP change will be necessary.
-
Cuff pressure gauges are the only recommended instrument to perform controls on endotracheal tube cuff pressure during anesthesia. No calibration is mandatory for these devices. The aim of this study was to describe the level of conformity of various cuff pressure gauges. ⋯ A minority of cuff pressure gauges went through our homologation criteria. These results demonstrate us that there is a real problem of the reliability and the follow-up of those medical devices. This study suggests to reinforce biomedical engineering control on these devices.
-
J Clin Monit Comput · Jun 2019
Letter Case ReportsPatent ductus arteriosus closure and somatic regional oxyhemoglobin saturation.
The authors report a case of a 14-day-old infant patient with patent ductus arteriosus (PDA) with pulmonary hypertension. Accidental clipping of the left pulmonary artery (LPA) during intended PDA closure was revealed, and subsequent urgent PDA closure and releasing a clip of the LPA were conducted. During surgeries we measured somatic regional oxyhemoglobin saturation (rSO2) values and change in those might be a key for early diagnosis of accidental clipping of the LPA. These findings suggest that we should understand the risk of accidental closure of the LPA during PDA surgery and somatic rSO2 values will provide information for early diagnosis of critical complication.
-
J Clin Monit Comput · Jun 2019
Optimizing target control of the vessel rich group with volatile anesthetics.
The ability to monitor the inspired and expired concentrations of volatile anesthetic gases in real time makes these drugs implicitly targetable. However, the end-tidal concentration only represents the concentration within the brain and the vessel rich group (VRG) at steady state, and very poorly approximates the VRG concentration during common dynamic situations such as initial uptake and emergence. How should the vaporization of anesthetic gases be controlled in order to optimally target VRG concentration in clinical practice? Using a generally accepted pharmacokinetic model of uptake and redistribution, a transfer function from the vaporizer setting to the VRG is established and transformed to the time domain. ⋯ Using a simple and clinically intuitive modification to the targeting algorithm, a variable low-pass boundary layer is applied to the actuation, smoothing discontinuities in the control law and practically eliminating chatter without prolonging the time taken to reach the VRG target concentration by any clinically significant degree. A model is derived for optimum VRG-targeted control of anesthetic vaporizers. An alternate and further application is described, in which deliberate perturbation of the vaporization permits non-invasive estimation of parameters such as cardiac output that are otherwise difficult to measure intra-operatively.