Effect of barcode technology on medication preparation safety: a quasi-experimental study.

BACKGROUND: Medication errors are a common problem in hospitals and a major driver of adverse patient outcomes. Barcode verification technology is a promising strategy to help ensure safe medication preparation practices. OBJECTIVES: The objectives of this study were (i) to assess the effects of a barcode-assisted medication preparation and administration system regarding the rate of medication preparation errors and (ii) to compare the time spent on medication preparation tasks by medical staff. METHODS: A quasi-experimental study with a pre-post design was conducted, from August 2017 to July 2018, in two mixed medical/surgical units of a tertiary teaching hospital. The primary aim was to assess the effects of a barcode-based electronically assisted medication preparation and administration system linked to the hospital's electronic medication administration record regarding the rate of medication preparation errors and time-based staff performance. Data were collected using direct observation. Adjusted and unadjusted logistic models were used for error frequencies and linear regression models for time performance. RESULTS: 5932 instances of medication selection and dosing during 79 medication preparation procedures were observed. The overall medication preparation error incidence decreased from 9.9% at baseline to 4.5% at post-intervention, corresponding to a relative risk reduction of 54.5% (P < 0.001). However, the adjusted effect by registered nurses (RNs) and nurses' work experience of total medication preparation errors showed only borderline significance (odds ratio [OR] 0.64, P = 0.051). For adjusted error-specific analyses, significant error reductions were found in wrong medication errors (OR 0.38, P < 0.010) and wrong dosage errors (OR 0.12, P = 0.004). Wrong patient, wrong form and ambiguous dispenser errors did not occur at post-intervention. Errors of omission (OR 1.53, P = 0.17), additional doses (OR 0.63, P = 0.64) and wrong dispenser boxes (OR 0.51, P = 0.11) did not change significantly. The time necessary to prepare medications for a 24-h period also decreased significantly-from 30.2 min to 17.2 min (beta = -6.5, P = 0.047), while mean preparation time per individual medication dose fell from 24.3 s to 15.1 s (beta = -5.0, P = 0.002). CONCLUSION: Use of the new barcode technology significantly reduced the rate of some medication preparation errors in our sample. Moreover, the time necessary for medication preparation, both per 24-h period and per single-medication dose, was significantly reduced.

[Closed-loop medication management: Results of a user survey]. / Elektronisch unterstützter Richt- und Abgabeprozess von Medikamenten im Universitätsspital: Ergebnisse einer Benutzerbefragung.

BACKGROUND: New technologies, such as bar-code scanning systems, have played a significant role in enhancing medication processes over recent years. Despite the documented benefits, integration, acceptance, and user opinion continue to play an important role in the successful implementation of such systems. To date no studies have been carried out in Switzerland to assess the attitude or acceptance of nurses towards electronically supported medication systems after implementation. This study was conducted in order to close this gap. METHODS: Following a four-month test phase of a closed-loop medication system on two mixed medical-surgical units in a tertiary teaching hospital, a cross-sectional online survey was conducted among the participating registered nurses (response rate: 62.5%). RESULTS: The new system was evaluated positively by the majority (70%) of users. Accordingly, the barcode-assisted medication process was proven to be especially beneficial to users during the 24-hour medication preparation process and during the preparation of infusions. However, user compliance decreased significantly during the administration of bedside medication and the preparation of additional single doses. This was mainly due to a lack of time and inadequate system performance. CONCLUSION: In the study, 75% of participants reported that they were open to or even enthusiastic about using the new technologies and were supportive of their introduction into the medication process. Overall, the majority rated the new system as beneficial to daily clinical practice, provided the technical performance was high.

Frequency of medication preparation and medication administration errors in a Swiss university Hospital. A prospective observational study / Häufigkeit von Richt- und Abgabefehlern von Medikamenten in einem Schweizer Universitätsspital. Eine prospektive Observationsstudie

Background: Prospective observational studies from Swiss university hospitals, focusing on the frequency of medication preparation and medication administration errors using direct observation, are still missing. To close this gap, we have conducted a scientific evaluation of an electronically assisted medication preparation and administration process in a Swiss university hospital. Aim: The aim of this study was to measure the frequency of medication preparation and medication administration errors in two units in a Swiss university hospital before the implementation of an electronically assisted medication preparation and administration process. Method: To fulfil the study aims we used direct observation of medical staff during the medication process, the gold standard to detect medication errors. Furthermore, we measured the time that medical staff used in order to prepare and administer medications. Results: During the baseline measure, we observed a total of 14 571 medication doses. Errors in the medication preparation stage occurred between 1 % and 7.6 % depending on unit and type of error. Medication administration errors ranged between 21 % and 27 %. The most frequent administration errors were due to wrong administration time (84.1 %). Conclusions: This is the first study conducted in a Swiss university hospital using direct observation to detect medication preparation and medication administration errors. The current study offers important basic data to evaluate the effect of an electronically assisted medication preparation and administration process scientifically.

A new 3D monitor-based random-dot stereotest for children.

PURPOSE: Objective testing for random-dot stereovision in preverbal children requires some type of dissociating glasses. Drawbacks of such methods are the alteration of natural visual conditions and sometimes nonacceptance of the glasses. For this reason, a new, natural method for random-dot stereopsis measurement was developed and tested. METHODS: Random-dot circles (diameter 10 cm, crossed disparity of 0.34 degrees ) were generated on an autostereoscopic display and presented to 18 normal children (mean age, 5.1 +/- 1.1 years), 8 with anisometropic amblyopia (mean age, 4.9 +/- 1.3 years), 14 with infantile essential esotropia (mean age, 5.3 +/- 0.7 years), and 16 with primary microstrabismus (mean age, 5.2 +/- 1.4 years). While the position of the stimulus randomly changed among four possible locations, eye positions were recorded by infrared photo-oculography. If two or more consecutive saccades ends corresponded to the stimulus coordinates, a positive response was assumed. The results with the new test were compared with the ability to recognize the Lang I random-dot stereotest. RESULTS: Twenty-four of 26 Lang I-positive children had positive responses (sensitivity of 92.3%), 29 of 30 Lang I-negative children had negative three-dimensional (3D) stimulus responses (specificity, 96.7%). The positive predictive value of the new test was 0.96 (95% CI, 0.79-0.99); the negative predictive value, 0.94 (95% CI, 0.78-0.99); and the overall accuracy, 0.95 (95% CI, 0.85-0.99). CONCLUSIONS: This new 3D monitor-based test allows objective assessment of random-dot stereopsis in children older than 3 years.

Development of visual pursuit in the first 6 years of life.

BACKGROUND: There are few previous investigations on the development of smooth visual pursuit in children. The aim of this study was to determine normative values for the development of horizontal and vertical smooth pursuit in a large number of normal children. METHODS: Eye movements of 358 healthy children aged 6 weeks through 6 years were recorded using infrared photo-oculography. Visual pursuit was elicited with colored squares of 1.2 degrees of visual angle. The stimulus moved horizontally or vertically with constant velocities of 7.5, 15, or 30 degrees/s. RESULTS: Attention time increased with increasing age from 0.54 to 0.77 (P<0.01) and decreased with increasing stimulus velocities (P<0.01). The ratio of time of smooth pursuit to time of smooth pursuit plus saccades increased with increasing age from 0.63 to 0.78 (P<0.01) and decreased with increasing stimulus velocities (P<0.01). For stimulus velocities of 7.5 degrees/s, no significant difference was found between horizontal and vertical gain values. For stimulus velocities of 15 degrees/s and 30 degrees/s, gains for horizontal movements were larger that for vertical (P<0.05). Increasing stimulus speeds were associated with decreasing gains (P<0.05). CONCLUSIONS: This study provides the following normative values for photo-oculography in healthy children aged 6 weeks through 6 years of age: attention time, smooth pursuit time, and gain for three stimulus velocities presented horizontally and vertically. This normative database should help to diagnose pathologic ophthalmological or neuropediatric conditions, to perform screening interventions, and to initiate therapies.

Influence of the Pulfrich phenomenon on driving performance.

BACKGROUND: The Pulfrich stereoillusion occurs spontaneously in diseases inducing asymmetric visual pathway delays. Its influence on driving performance has never been investigated and was, therefore, assessed using a three-dimensional (3D) computer driving simulation. METHODS: A 3D driving scenery of a road with obstacles was visualised on an autostereoscopic 3D display. Seven normal subjects drove at a speed of 6 m/s using a steering wheel and three angles of view of the scenery (0 degrees, 45 degrees to left, and 90 degrees to left) with different interocular delays (25 ms on the right, 25 ms on the left, and no delay). One subject drove the scenery at an angle of 90 degrees without delay and with a delay of 8 ms, 16 ms, and 25 ms on the right and left, respectively, at speeds of 6 m/s, 12 m/s and 18 m/s. RESULTS: Stereo-illusion only influenced car position if the angle of view was 90 degrees (p<0.05). At this angle, increasing car speeds were associated with larger car displacements (delay on right p<0.001, on left p<0.01) and smaller delays with smaller car displacements (p<0.001). CONCLUSIONS: This study showed that Pulfrich phenomenon has an influence on car position only if the viewing angle is 90 degrees. No influence could be found if the driving direction corresponded to the visual axis of the driver. These findings are in agreement with reports of patients with spontaneous Pulfrich phenomenon who indicate that while driving, distances are only misjudged when looking sideways.

[A new method to test vertical ocular deviations using perilimbal light reflexes]. / Eine neue Methode zur Messung von vertikalen okulären Abweichungen mittels des Perilimbalreflexes.

BACKGROUND: To develop a new diagnostic technique to determine vertical ocular deviations when the center of the pupil is covered by swollen eyelids in up- and downgaze. PATIENTS AND METHODS: In upgaze (downgaze) the reflex of a diagnostic lamp held at about 50 cm distance from the patient is observed on the lower (upper) limbus. In the case of an asymmetric reflex, prisms are used to obtain symmetrical reflexes. The amount of prisms indicates the size of the vertical misalignment. In five healthy volunteers, the angles of vertical changes of gaze position were plotted against the prism size needed to recenter the perilimbal reflex. RESULTS: There was a linear correlation between the amount of upgaze changes in degrees and the strength of prisms used for compensation in degrees. This linear correlation was also found in downgaze. For both the correlation coefficient was r = 0.98 +/- 0.01. In upgaze the slope of the average regression line was 0.55 +/- 2.3 degrees, in downgaze - 4.1 +/- 0.8 degrees. A prism of 1 degrees corresponds in upgaze to a vertical deviation of about 1.3 +/- 0.14 degrees, in downgaze to a deviation of about 1.1 +/- 0.07 degrees. CONCLUSIONS: These results demonstrate that the perilimbal light reflex test is suitable for measuring simulated vertical ocular deviations. Therefore, the test may also be used in patients with vertical deviations who cannot be measured with classical methods. The method is more exact for measurements in upgaze.

[A new objective visual acuity test: an automated preferential looking]. / Neues objektives Diagnoseverfahren zur Sehschärfenbestimmung: ein automatisiertes Preferential-Looking.

BACKGROUND: The Preferential Looking test using Teller acuity cards is widely used for preverbal children but has some weaknesses, in particular because it is examiner dependent and at best half-objective. We tested a new automated method in a pilot study. PATIENTS AND METHODS: In our preferential looking setting we project separate images into the left and right eye. This permits measuring each eye without having to cover the other. An infrared oculography system documents objectively and reproducibly whether or not the stimulus is seen. A square is shown which moves consecutively in a square formation on a background that has the same average brightness. Charting an XY-plot of the eye position results in a square with two diagonals, if the stimulus is seen. By using a specific baby examination unit, this test is already feasible in babies. In this study, the new setting was tested on two children. RESULTS: In two healthy children we found a good correlation between visual acuities determined with the new method and Teller visual acuity charts. Fogging one eye in each of the children resulted in fixation loss of the stimulus when the required visual acuity rose above the fogging value. CONCLUSIONS: This new technique permits one to perform an objective preferential looking test without the need of verbal answers. Larger studies have to validate these preliminary results.

[A new objective test for random-dot stereopsis in preverbal children]. / Ein neues objektives Testverfahren für Random-Dot-Stereopsis bei präverbalen Kindern.

BACKGROUND: The Lang-Stereotest is at best half-objective in testing stereovision in preverbal children. We developed a new method which might objectively measure random-dot stereopsis in preverbal children. PATIENTS AND METHODS: We project two separate random-dot images into the left and right eye using a 3D-monitor. If both eyes are perfectly aligned and random stereopsis is present, the child perceives a stimulus. Four different stimulus positions are shown at random. An infrared oculography system objectively detects whether the stimuli are seen. By using a specific baby examination unit, testing is already feasible in infants. RESULTS: We present the plots of two children with a positive (normal) and two with a negative (pathologic) response to random-dot stimuli. CONCLUSIONS: This new examination technique allows an objective assessment of random-dot stereopsis in non-verbal children. It permits us for the first time to study the development of stereovision under natural conditions. In future, the method may also be used to screen preverbal children for visual abnormalities. Larger studies are required to determine the positive and negative predictive values of this new test.