Development of optimized adult epidural infusion preparations to reduce waste and improve operational efficiency

DISCLAIMER

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PURPOSE

Despite national recommendations to standardize infusion concentrations, there is minimal guidance on institution-specific strategies and outcomes related to epidural infusion concentration standardization and optimization. The purpose of this project is to identify the optimal compounded preparation for use in select adult epidural infusions and assess the impact on drug and fluid utilization and cost savings if the designated preparation is adopted.

METHODS

A previously validated tool, the VERB (vial, exchange, rate, and bag) analysis, was applied to epidural infusion pump administration data to identify preparations optimized for efficient supply and resource utilization at a large academic medical center.

RESULTS

Weighing all components of the VERB analysis, the preferred preparation of hydromorphone and bupivacaine for the hospital site was hydromorphone (10 µg/mL) and bupivacaine (0.125%) in 50 mL of 0.9% sodium chloride injection (2,500 µg of hydromorphone per epidural). The preferred preparation of fentanyl and bupivacaine was fentanyl (2 µg/mL) and bupivacaine (0.0625%) in 50 mL of 0.9% sodium chloride injection (100 µg of fentanyl per epidural). Both recommendations are different from the currently utilized preparations at the study site.

CONCLUSION

Analyzing historic drug administration data using the novel 4-step VERB analysis identified optimized drug preparations and fluid bag sizes for the most-prescribed epidural drug combinations at the hospital study site.

Soundless Trouble: Syringe Pump Malfunction and the Hypotension Threat

Drug infusion devices have become indispensable tools in ICU patient care, drug delivery, and operation rooms (OR) and for controlled fluid delivery. Syringe pump safety is paramount in healthcare and laboratory settings to ensure accurate medication delivery and prevent adverse events. Healthcare professionals must receive thorough training on syringe pump operation, including loading syringes, programming infusion rates, and responding to alarms. Using the correct syringe size and type is essential to prevent inaccuracies in drug/fluid delivery. Regular calibration and maintenance checks are necessary to ensure the accuracy and reliability of the syringe pumps. Two cases of refractory hypotension are reported here, which were resolved by careful inspection of the infusion pumps.

Infants With Dorsal Hand Compartment Syndrome Due to Intravenous Infiltration of Glucose Acetate Ringer's Solution

Compartment syndrome caused by glucose acetate Ringer's solution in children has not been sufficiently reported. We report the cases of two children who developed compartment syndrome of the dorsum of the hand and forearm after receiving only glucose acetate Ringer's solution during hospitalization, with one case requiring a releasing incision. In recent years, glucose acetate Ringer's solution has been frequently used for maintenance infusion. However, it is not always safe and should be used with caution due to the risk of serious side effects caused by infiltration.

The effect of patient's body weight, infusion connection point, and infusion pump position on intravenous multi-infusion drug delivery at low infusion rates suitable for premature neonates

INTRODUCTION

Parenteral drug administration in the neonatal intensive care involves complex pharmacotherapy adjusted for the patient's weight, fluid allowance, and complex multi-infusion systems.

OBJECTIVES

We investigated the delivery rate of a model drug through a multi-infusion system consisting of six intravenous infusions.

METHODS

Delivery rate of the model drug was determined after infusion initiation and termination. Measurements were collected spectrophotometrically in real time. Time to drug delivery and the amount of drug delivered were measured.

KEY FINDINGS

The longest time to drug delivery was observed for a 500 g neonate model with a distal infusion connection point and neutral pump position (337 ± 30 min, P < 0.001). The shortest time was observed for a 1000 g neonate model in the combination of proximal infusion connection point and neutral pump position (18 ± 12 min, P < 0.05). The expected 100% of the drug was delivered only in two combinations: 500 g and 1000 g neonate models, proximal infusion connection point and neutral pump position (100.4 ± 4.7%, P = 0.819 and 100.2 ± 2.7%, P = 0.874, respectively). While the least drug was delivered to a 500 g neonate model in the combination of distal infusion connection point and neutral pump position (27.5 ± 5.8%, P < 0.001).

CONCLUSIONS

Delayed drug delivery to premature neonates due to multi-infusion systems may compromise accurate drug administration and lead to dosing errors.

Mapping Injection Order Messages to Health Level 7 Fast Healthcare Interoperability Resources to Collate Infusion Pump Data

BACKGROUND

When administering an infusion to a patient, it is necessary to verify that the infusion pump settings are in accordance with the injection orders provided by the physician. However, the infusion rate entered into the infusion pump by the health care provider cannot be automatically reconciled with the injection order information entered into the electronic medical records (EMRs). This is because of the difficulty in linking the infusion rate entered into the infusion pump by the health care provider with the injection order information entered into the EMRs.

OBJECTIVES

This study investigated a data linkage method for reconciling infusion pump settings with injection orders in the EMRs.

METHODS

We devised and implemented a mechanism to convert injection order information into the Health Level 7 Fast Healthcare Interoperability Resources (FHIR), a new health information exchange standard, and match it with an infusion pump management system in a standard and simple manner using a REpresentational State Transfer (REST) application programming interface (API). The injection order information was extracted from Standardized Structured Medical Record Information Exchange version 2 International Organization for Standardization/technical specification 24289:2021 and was converted to the FHIR format using a commercially supplied FHIR conversion module and our own mapping definition. Data were also sent to the infusion pump management system using the REST Web API.

RESULTS

Information necessary for injection implementation in hospital wards can be transferred to FHIR and linked. The infusion pump management system application screen allowed the confirmation that the two pieces of information matched, and it displayed an error message if they did not.

CONCLUSION

Using FHIR, the data linkage between EMRs and infusion pump management systems can be smoothly implemented. We plan to develop a new mechanism that contributes to medical safety through the actual implementation and verification of this matching system.

Development of a proactive process to harmonize policy, infusion pump library, and electronic health record entries for continuous infusions at an academic medical center

PURPOSE

Standardized processes to order and prepare medications can decrease the potential for error and provider uncertainty. Our health system utilizes a standard concentration policy, smart infusion pumps, and the electronic health record (EHR) to catalog, order, and deliver intravenous medications. A need for a more proactive and formalized process to ensure medication listings are harmonized between these 3 resources was identified. Standardizing these resources can reduce confusion, reduce time spent in pharmacy operations and nursing workflow, and may improve patient safety. The purpose of this quality improvement project was to compare and resolve inconsistencies between these 3 sources and to create a new process to assure uniformity in a complex work environment.

SUMMARY

An audit-style comparison and evaluation of entries for continuous infusions within the standard concentration policy, the pump library, and the EHR was conducted. All continuous infusion entries within any one of these 3 sources were included. Key exclusion criteria included pediatric and neonatal infusions, intermittent infusions, and infusions in procedural areas. We compared the policy, the pump library, and the EHR to identify, document, and resolve discrepancies in medication name, concentration, rate, and volume; fluid restriction concentration; and upper and lower pump limits. A new method to ensure proactive continuity and consistent updates to the 3 sources was implemented into existing operational workflows. We recommended a total of 82 updates to policy (n = 48), the pump library (n = 30), and the EHR (n = 4) out of 187 continuous infusion entries.

CONCLUSION

Standardizing infusion resources will reduce confusion, and improve pharmacy operations, nursing workflow, and patient safety.

Nurses' Perceptions of Infusion Therapy During the COVID-19 Pandemic

During the COVID-19 pandemic, nurses were faced with challenges when caring for patients, safely administering intravenous (IV) medications and solutions, and protecting themselves from the virus. To address these challenges, nurses moved infusion pumps outside of intensive care unit (ICU) rooms of patients with COVID-19 to minimize their exposure to the virus, conserve personal protective equipment, and efficiently administer IV medications and solutions. The purpose of this qualitative descriptive study was to explore and describe nurses' perception of managing infusion pumps outside the ICU rooms of patients with COVID-19 at 6 acute care hospitals. Eight interviews were conducted with ICU nurse managers, assistant nurse managers, clinical nurses, and vascular access team staff. From the interviews, the overarching theme was "figure out a way," with the subtheme "no clear-cut policy." Additional themes were: (1) limiting nurses' exposure, (2) increased risk for infection and error, (3) teamwork, and (4) roller coaster of emotions. The findings from this study revealed that, during this unprecedented pandemic, nurses were innovative and figured out a way to care for patients who were critically ill with COVID-19. Understanding this experience provides insight into creating policies and procedures to guide patient care in future pandemics or emergency care.

[Application of Data Analysis and Data Visualization in Medical Equipment: Take Infusion Pump as Example]

OBJECTIVE

To combine data analysis and data visualization with medical devices, provide a set of data analysis and data visualization solutions. This solutions can deeply excavate the data of the whole life cycle of medical equipment, and then play a guiding role in business.

METHODS

With the help of mature tools in the Internet field, YIYI and YOUSHU, we can quickly complete data collection and rich visualization effects, and introduce the concept of data analysis to deeply mine data.

RESULTS

Taking the maintenance data of infusion pump as an example, the data collection is completed through YIYI, and the maintenance system is built on YOUSHU.

CONCLUSIONS

The maintenance system of infusion pump system is simple and clear, with good visualization effect. It can quickly analyze maintenance failures, reduce maintenance times and maintenance costs, ensure the safety of the equipment. Moreover, the system can be easily transferred to other medical equipment, and can carry on the whole life cycle data research.

Defining the Current Deployment of Neonatal Infusion Pumps in Low- and Lower-Middle-Income Countries: A Rapid Review

There has been limited review of the reported deployment of infusion pumps in low- and lower-middle-income countries. This paper aims to identify the current distribution of infusion pumps in low- and lower-middle-income countries (LLMICs) used to treat neonates. A rapid review was conducted using material sourced from ProQuest, Pubmed, Web of Science, and IEEE Xplore. Twenty-six search results met the inclusion criteria. Within these, 41 neonatal healthcare facilities were discussed with 17 of the facilities having infusion pumps available, 13 limited access, and 11 none. Infusion pump use remains limited in Sub-Saharan Africa so efforts should be made to deploy specialist neonatal care improvement packages, potentially including infusion pumps designed for LLMICs. The effects of COVID-19, to neonatal care LLMICs, should be accessed to ensure progress has not regressed. These proposals aim to aid in the continued improvement of neonatal care globally and reduce newborn mortalities.

[Some Problems and Risk Analysis of Infusion Pump Instructions]

OBJECTIVE

10 instructions of infusion pumps were contrasted and analyzed in order to explore the problems of instructions, furthermore improve the product safety.

METHODS

Analyzed the scopes of application, requirements of infusion apparatus, maintenance methods and cycles, battery maintenance, and service life, etc.

RESULTS

There were 5 products in 10 which did not indicate contraindications. One product only provided the thickness range of the tube wall of the infusion apparatus instead of specific brands. The cleaning cycles of 9 products varied from 2 to 12 months. One product did not clarify the service life.

CONCLUSIONS

It is recommended that manufactures should improve the product instructions to ensure the safety of infusion pumps.

Intercountry comparisons of advanced Parkinson's disease symptoms and management: Analysis from the OBSERVE-PD observational study

Objectives

In the absence of widely accepted criteria, determining when a patient with Parkinson's disease (PD) may benefit from more advanced treatments such as device‐aided therapy (DAT) so far remains a matter of physician judgment. This analysis investigates how classification of PD varies across countries relative to measures of disease severity.

Materials and Methods

The OBSERVational, cross‐sEctional PD (OBSERVE‐PD) study included consecutive patients with PD at centers that offer DATs in 18 countries. In this subgroup analysis, we explore intercountry differences in identification of advanced versus non‐advanced PD based on physician's clinical judgment, symptoms assessed using Delphi consensus criteria, use of DAT, motor and non‐motor symptoms, and caregiver support. Demographic and clinical characteristics were obtained through review of medical records.

Results

Overall, 1342 of 2615 patients (51.3%) were assessed by physicians as having advanced PD. The proportion of patients in different countries identified as having advanced PD (24.4–82.2%) varied. In 15 of 18 countries, a greater proportion of patients with advanced PD, according to select Delphi criteria, were identified by physicians as having advanced PD than with non‐advanced PD. There was a wide variability across countries in the proportion of patients with no dyskinesia, disabling dyskinesia, dyskinesia pain, and non‐motor symptoms who were identified by physicians as having advanced versus non‐advanced PD.

Conclusions

The proportion of patients identified with advanced PD symptoms varies widely across countries, despite differences on the patients' profiles, indicating a need for objective diagnostic criteria to help identify patients who may benefit from DAT.

[Optimization of Quality Control Efficiency of Infusion Pump]

OBJECTIVE

Analyze and conclude the new quality control process, so as to improve the quality control efficiency.

METHODS

Statistical analysis was conducted on the flow rate quality control data of infusion pump in 2020, with a total of 330 times of quality control data.

RESULTS

The pump with qualified flow rate entered and maintained the qualified state from the third minute, while the pump with unqualified flow rate entered and maintained the unqualified state from the second minute.

CONCLUSIONS

Take the third minute to enter the qualified range and continue for 2 minutes to judge that the flow rate quality control is qualified. The accuracy of this new rule is as high as 100%, and the time of flow rate quality control can be reduced from 60 minutes to 10 minutes, which greatly improves the work efficiency.

Effect of modern infusion pumps on RBC quality

BACKGROUND

Mechanical stress on red blood cells is associated with using infusion pumps for blood administration. Current standards in North America leave it to healthcare facilities to consult with manufacturers about infusion pump safety for transfusion; studies on various pumps and red blood cell (RBC) conditions are scarce.

STUDY DESIGN AND METHODS

RBC units were pumped through four infusion pumps on d22 (22 days postcollection), d40, d28 after gamma irradiation on d14 (I14d28), and d22 after irradiation on d21 (I21d22). For each experiment, three units were pooled and split among four bags. Samples were collected at gravity and after pumping at clinical nonemergency rates. Hemolysis %, microvesicles, potassium, lactate dehydrogenase, mechanical fragility index levels, and morphology evaluations were performed (n = 5-6).

RESULTS

Hemolysis levels of Piston and Linear Peristaltic pump samples were not different from hemolysis of corresponding gravity samples. Peristaltic samples had significantly higher hemolysis compared to gravity, and other pumps, however, maximum mean difference was limited to 0.05%. Pumping at 50 mL/h resulted in the highest hemolysis level. Change in hemolysis % due to pumping was significantly higher in d40 and I21d22 units. No combination of pumps and RBCs conditions led to hemolysis >0.8%. Besides hemolysis, lactate dehydrogenase release was the only marker that demonstrated some differences between infusions via pump versus gravity.

CONCLUSION

The pump design affects the degree of hemolysis. However, for all tested pumps and RBC conditions, this increase was minimal. Hemolysis measurement on d40 and I21d22 at 50 mL/h were concluded to be appropriate parameters for pump evaluation.

Real-Life Use of Levodopa/Carbidopa Intestinal Gel in Parkinson's Disease According to Analysis of Pump Data

BACKGROUND

Levodopa/carbidopa intestinal gel (LCIG) infusion is an efficacious treatment of motor and non-motor fluctuations in people with Parkinson's disease (PD). Real-life use of the treatment is not previously studied.

OBJECTIVE

The aims of the study were to explore the use of LCIG and to determine how extra doses of LCIG are used in daily life.

METHODS

Twenty-five PD patients with ongoing LCIG therapy were consecutively included. Pump data was retrieved from 30 days on average, by means of software, extracting the most recent pump events.

RESULTS

The daily duration of infusion was 15 hours on average, in 18 patients, whereas the remaining 7 patients used 24-hour infusion. Morning doses ranged from 38-190 mg levodopa, for patients who utilized this function. Median number of daily extra doses was 2.5 (range: 0-10.6) and median size of the extra dose was 24 mg (0-80 mg) levodopa. Median total daily levodopa intake with LCIG was 1201 mg (range: 417-2322 mg).

CONCLUSION

Retrieving pump data is possible and may be important for evaluating the at-home use of LCIG, to optimize the therapy. Adherence to treatment should be monitored, which is not technically difficult, at least in device-aided treatments for PD.

Combining Device-Aided Therapies in Parkinson's Disease: A Case Series and a Literature Review

Background

Deep brain stimulation (DBS), levodopa-carbidopa intestinal gel (LCIG) and subcutaneous apomorphine infusion are device-aided therapies (DATs) for advanced Parkinson's disease (PD). We present a case series from the Cretan PD Registry who required 2 DATs for optimal management along with a systematic review of similar studies.

Cases

From 2009 to 2020, we retrospectively studied all PD patients who were simultaneously treated with 2 DATs. Six patients on DBS required an infusion treatment for persisting or re-emergent fluctuations because of disease progression. Two patients on LCIG infusion received DBS as a levodopa-sparing strategy because of drug-induced complications. Fluctuations and quality of life improved in all patients.

Literature review

We identified 4 case series, 1 prospective and 1 retrospective study that included a total of 50 DBS-treated patients who required an infusion therapy. Improvement in motor outcomes, assessed in different ways, was a constant finding.

Conclusions

Selected PD patients on 1 DAT may experience additional benefit from a second DAT, for several reasons along the course of their disease. Although infusion therapies optimize dopaminergic drug delivery in fluctuating DBS-treated patients, DBS added on LCIG treatment has an additive symptomatic effect that allows levodopa dose reduction in patients with drug-induced side effects.

Quantitative assessment of infusion pump-mediated haemolysis in feline packed red blood cell transfusions

OBJECTIVES

Haemolysis caused by the use of peristaltic infusion pumps (PIPs) has been described in human and canine packed red blood cells (pRBCs). The aim of this study was to evaluate the effects of two different linear PIPs on the haemolysis of feline pRBC units stored for a long time.

METHODS

Feline pRBC units stored with adenine, dextrose, mannitol and sodium chloride (SAGM) were manufactured. After 35-42 days of storage at 2-4°C, a line administration system with a 180 µm filter was attached to every pRBC bag, the system was drained by gravity alone (8 drops/min) and a 1.3 ml sample was collected (G). A NIKI V4 pump was then used at a flow rate of 25 ml/h, the flow was stopped when the infusion system was filled with blood coming from the infusion pump and another 1.3 ml sample was collected (NK). Finally, an Infusomat FmS pump was evaluated, collecting another 1.3 ml sample (IM). Packed cell volume (PCV) was measured in all samples by microhaematocrit centrifugation, total haemoglobin (HGB) was measured using a specific haemoglobin analyser and, after centrifugation, free HGB was determined by spectrophotometry. The percentage of haemolysis was calculated. Friedman's test was used to compare the samples.

RESULTS

Fifteen feline pRBC units were evaluated. The average degree of haemolysis for sample G (gravity-assisted) was 1.12%. Comparison of the degree of gravity-assisted haemolysis with haemolysis in PIP NK (1.13%) and IM (1.14%) samples revealed no significant differences, with differences of only 0.01% and 0.02%, respectively.

CONCLUSIONS AND RELEVANCE

The results of this study demonstrate that the use of two common PIPs in veterinary hospitals does not produce levels of haemolysis that are significantly different than that caused by gravity alone during transfusion of feline pRBCs at a rate of 25 ml/h.

Using intravenous pump infusion data to optimize continuous infusion concentrations and reduce drug and fluid waste

PURPOSE

To outline a data-driven analysis involving use of intravenous (i.v.) pump data to identify optimal drug and fluid amounts for various continuous infusions, with the primary goal of minimizing medication waste. This methodology incorporates analysis of vial sizes, infusion rates, number of bag exchanges, and bag volumes to determine optimal concentrations that improve operational efficiencies and decrease drug and fluid waste.

METHODS

A retrospective evaluation of i.v. infusion pump utilization data for continuous infusions of norepinephrine, phenylephrine, vasopressin, and cisatracurium was performed using data provided by 9 hospitals in North Carolina during January, April, and June of 2015.

RESULTS

The recommended medication concentrations and fluid volumes were determined using a novel 4-step analysis, the VERB (Vial, Exchange, Rate, and Bag) analysis, which applied optimal practices for cost reduction, operational efficiency, and patient safety. The application of the VERB analysis to the i.v. infusion pump utilization data resulted in the following recommended medication concentrations: norepinephrine, 4 mg/100 mL (final concentration, 40 µg/mL) and 16 mg/250 mL (final concentration, 64 µg/mL); phenylephrine, 10 mg/100 mL (final concentration, 100 µg/mL); vasopressin, 20 units/100 mL (final concentration, 0.2 unit/mL); and cisatracurium, 200 mg/100 mL (final concentration, 2 mg/mL). It was determined that implementation of the recommended concentrations by the 9 study hospitals would result in significant medication cost savings and fluid volume savings.

CONCLUSION

Analysis of i.v. infusion pump data from multiple hospitals using VERB analysis resulted in standardized medication concentrations and bag sizes for continuous infusions that reduce drug and fluid waste and improve operational efficiencies.

Flow irregularities from syringe infusion pumps caused by syringe stiction

OBJECTIVE

The current study aimed to evaluate the extent of the slide-stick phenomenon in differently designed infusion syringes at various infusion rates and filling positions.

METHODS

Fluid delivery from three 50-mL infusion syringe brands (BD; Codan; Fresenius) was investigated using a flow sensor at flow rates of 0.5, 1.0, or 5.0 mL h^-1 , with the syringes filled with either 10, 30, or 50 mL of distilled water. Two identical models (A/B) of the same infusion pump model were used. The effect of flow rate variations on the plasma concentration of a continuous epinephrine infusion in a 3 kg neonate receiving a continuous infusion of 0.1 μg kg min^-1 epinephrine was studied using a pharmacokinetic simulation model.

RESULTS

Considerable variations in calculated plasma epinephrine concentration were detected between flow rates of 5 and 0.5 or 1 mL h^-1 for all syringe types and filling volumes. The median deviation of plasma concentration for the 5 mL h^-1 flow rate varied depending on assembly from 1.3% (Codan) to 1.8% (Fresenius). This was more pronounced for lower flow rates, where at 1 mL h^-1 the deviation varied from 3.3% (BD) to 4.8% (Fresenius) and at 0.5 mL h^-1 from 4.9% (BD) to 5.4% (Fresenius). Differences between filling volumes (within syringe type and flow rate) did not appear to have relevant influence on variations in calculated plasma epinephrine concentration.

CONCLUSION

Infusion set rate rather than syringe brand or filling volume was a major predictor for syringe stiction-related amount of variation in the calculated plasma epinephrine concentration.

Minimising haemodynamic lability during changeover of syringes infusing norepinephrine in adult critical care patients: a multicentre randomised controlled trial

BACKGROUND

Arterial pressure lability is common during the process of replacing syringes used for norepinephrine infusions in critically ill patients. It is unclear if there is an optimal approach to minimise arterial pressure instability during this procedures. We investigated whether 'double pumping' changeover (DPC) or automated changeover (AC) reduced blood pressure lability in critically ill adults compared with quick syringe changeover (QC).

METHODS

Patients requiring a norepinephrine infusion syringe change were randomised in a non-blinded trial undertaken in six ICUs. Randomisation was minimised by norepinephrine flow rate at inclusion and centre. The primary outcome was the frequency of increased/decreased mean arterial pressure (defined by </>15 mm Hg from baseline measurements) within 15 min of switching the syringe compared with QC.

RESULTS

Patients (mean age: 64 (range:18-88)) yr were randomly assigned to QC (n=95), DPC (n=95), or AC (n=96). Increased MAP was the commonest consequence of syringe changeovers. MAP variability was most frequent after DPC (89/224 changeovers; 39.7%) compared with 57/223 (25.6%) changeovers after quick syringe switch and 46/181 (25.4%) in patients randomised to receive automated changeover (P=0.001). Fewer events occurred with QC compared with DPC (P=0.002). Sensitivity analysis based on mixed models showed that performing several changeovers on a single patient had no impact. Both type of changeover and norepinephrine dose before syringe changeover were independently associated with MAP variations >15 mm Hg.

CONCLUSIONS

Quick changeover of norepinephrine syringes was associated with less blood pressure lability compared with DPC. The prevalence of MAP variations was the same between AC and QC.

CLINICAL TRIAL REGISTRATION

NCT02304939.

Ultrasound-guided continuous block of median and ulnar nerves in horses: development of the technique

OBJECTIVE

To develop a technique for ultrasound-guided continuous median and ulnar peripheral nerve block in horses.

STUDY DESIGN

Anatomical and prospective experimental study.

ANIMALS

A total of 16 thoracic limbs from horse cadavers and 18 adult horses.

METHOD

This study was conducted in three phases. Phase 1: Dissection of median and ulnar nerves in the antebrachial region of two cadaver limbs to identify localizing landmarks. Description of sonoanatomy in 14 cadaver limbs using ultrasound-guided perineural infiltration of a combination of cellulose gel (5 mL), contrast medium (4 mL) and methylene blue (1 mL). Catheters were inserted between the perineural sheath and epineurium in six limbs, followed by computed tomography. Phase 2: Ultrasonographic images of the limbs of 18 healthy horses of different breeds were used to define an acoustic window and optimize the approach to nerves. Phase 3: Two case reports of horses with chronic pain of different etiologies. Catheters were inserted between the epineurium and paraneural sheath of the median and/or ulnar nerves guided by ultrasound, followed by continuous infusion of 0.4% ropivacaine.

RESULTS

Information from phase 1 was used to direct needle insertion, solution dispersion and catheter implantation in phase 2, which resulted in 100% technique accuracy. In response to the peripheral nerve block, pain reduction was apparent in the two clinical cases by increased weight bearing in affected limbs and decreased requirement for systemic analgesic medications. No local reactions were observed.

CONCLUSIONS AND CLINICAL RELEVANCE

The ultrasound technique allowed real-time visualization of needle, catheter and drug dispersion and resulted in a high success rate for nerve blocks. The horses administered a median and ulnar nerve block exhibited no discomfort or signs of infection at the catheter insertion site. Further studies are warranted to validate the efficacy of this technique.

Performance of modern syringe infusion pump assemblies at low infusion rates in the perioperative setting

BACKGROUND

Syringe infusion pumps are used for the precise continuous administration of intravenous drugs. Their compliance and mechanical deficiencies have been found to cause considerable start-up delays, flow irregularities during vertical displacement, as well extensive delays of occlusion alarms at low infusion rates. The aim of this study was to evaluate the performance of several modern syringe infusion pumps at low infusion rates and the impact on drug concentration.

METHODS

Seven currently marketed syringe infusion pump assemblies were assessed in an in vitro study during start-up, vertical displacement manoeuvres, and infusion line occlusion at a set flow rate of 1 ml h^-1. The measured data were used as input for a pharmacokinetic simulation modelling plasma concentration during a standard neonatal continuous epinephrine infusion.

RESULTS

The mean time from starting the infusion pump to steady-state flow varied from 89 to 1622 s. The zero-drug delivery time after lowering the pump ranged from 145 to 335 s. In all assemblies tested, occlusion alarm delays and measured flow irregularities during vertical displacement manoeuvres resulted in relevant deviations in plasma epinephrine concentration (>25%) as calculated by the pharmacokinetic simulation model.

CONCLUSION

Problems with the performance of syringe infusion pump assemblies can have considerable impact on plasma drug concentration when highly concentrated short-acting cardiovascular drugs are administered at low flow rates. The problems, which affected all assemblies tested, are mainly related to the functional principle of syringe infusion pumps and will only partially be solved by incremental improvements of existing equipment.

Types and Frequency of Infusion Pump Alarms and Infusion-Interruption to Infusion-Recovery Times for Critical Short Half-Life Infusions: Retrospective Data Analysis

BACKGROUND

Alarm fatigue commonly leads to a reduced response to alarms. Appropriate and timely response to intravenous pump alarms is crucial to infusion continuity. The difficulty of filtering out critical short half-life infusion alarms from nonurgent alarms is a key challenge for risk management for clinicians. Critical care areas provide ample opportunities for intravenous medication error with the frequent administration of high-alert, critical short half-life infusions that require rigorous maintenance for continuity of delivery. Most serious medication errors in critical care occur during the execution of treatment, with performance-level failures outweighing rule-based or knowledge-based mistakes.

OBJECTIVE

One objective of this study was to establish baseline data for the types and frequency of alarms that critical care clinicians are exposed to from a variety of infusion devices, including both large volume pumps and syringe drivers. Another objective was to identify the volume of these alarms that specifically relate to critical short half-life infusions and to evaluate user response times to alarms from infusion devices delivering these particular infusions.

METHODS

The event logs of 1183 infusion pumps used in critical care environments and in general care areas within the European region were mined for a range of alarm states. The study then focused on a selection of infusion alarms from devices delivering critical short half-life infusions that would warrant rapid attention from clinicians in order to avoid potentially harmful prolonged infusion interruption. The reaction time of clinicians to infusion-interruption states and alarms for the selected critical short half-life infusions was then calculated.

RESULTS

Initial analysis showed a mean average of 4.50 alarms per infusion in the general critical care pump population as opposed to the whole hospital rate of 1.39. In the pediatric intensive care unit (PICU) group, the alarms per infusion value was significantly above the mean average for all critical care areas, with 8.61 alarms per infusion. Infusion-interruption of critical short half-life infusions was found to be a significant problem in all areas of the general critical care pump population, with a significant number of downstream (ie, vein and access) occlusion events noted. While the mean and median response times to critical short half-life infusion interruptions were generally within the half-lives of the selected medications, there was a high prevalence of outliers in terms of reaction times for all the critical short half-life infusions studied.

CONCLUSIONS

This study gives an indication of what might be expected in critical care environments in terms of the volume of general infusion alarms and critical short half-life infusion alarms, as well as for clinician reaction times to critical short half-life infusion-interruption events. This study also identifies potentially problematic areas of the hospital for alarm fatigue and for particular issues of infusion and infusion-line management. Application of the proposed protocols can help create benchmarks for pump alarm management and clinician reaction times. These protocols can be applied to studies on the impact of alarm fatigue and for the evaluation of protocols, infusion-monitoring strategies, and infusion pump-based medication safety software aimed at reducing alarm fatigue and ensuring the maintenance of critical short half-life infusions. Given the frequency of infusion alarms seen in this study, the risk of alarm fatigue due to the white noise of pump alarms present in critical care, to which clinicians are constantly exposed, is very high. Furthermore, the added difficulties of maintaining critical short half-life infusions, and other infusions in specialist areas, are made clear by the high ratio of downstream occlusion to infusion starts in the neonatal intensive care unit (NICU). The ability to quantitatively track the volume of alarms and clinician reaction times contributes to a greater understanding of the issues of alarm fatigue in intensive care units. This can be applied to clinical audit, can allow for targeted training to reduce nuisance alarms, and can aid in planning for improvement in the key area of maintenance of steady-state plasma levels of critical short half-life infusions. One clear conclusion is that the medication administration rights should be extended to include right maintenance and ensured delivery continuity of critical short half-life infusions.

Evaluation of a novel flow-controlled syringe infusion pump for precise and continuous drug delivery at low flow rates: a laboratory study

Syringe infusion pumps are used for the administration of short-acting drugs in anaesthesia and critical care medicine, but are prone to flow irregularities at low flow rates. A flow-controlled syringe infusion pump using an integrated flow sensor for feedback control represents a new approach to overcoming these limitations. This study compares the performance of a prototype flow-controlled syringe pump both at start-up, and during vertical displacement manoeuvres, with that of a standard infusion syringe pump. The novel pump almost completely eliminated delays at start-up and flow irregularities during hydrostatic pressure changes. Related fluctuations in plasma drug concentration were minimised and the known disadvantages of standard syringe infusion pumps currently used in clinical practice were reduced. Besides providing fast start-up to steady-state flow and precise continuous drug delivery at low flow rates during hydrostatic pressure changes, the new pump offers the potential for the development of target-controlled infusion algorithms for short-acting cardiovascular and other drugs.

A Hazard Analysis of Class I Recalls of Infusion Pumps

BACKGROUND

The adverse event report of medical devices is one of the postmarket surveillance tools used by regulators to monitor device performance, detect potential device-related safety issues, and contribute to benefit-risk assessments of these products. However, with the development of the related technologies and market, the number of adverse events has also been on the rise, which in turn results in the need to develop efficient tools that help to analyze adverse events monitoring data and to identify risk signals.

OBJECTIVE

This study aimed to establish a hazard classification framework of medical devices and to apply it over practical adverse event data on infusion pumps. Subsequently, it aimed to analyze the risks of infusion pumps and to provide a reference for the risk management of this type of device.

METHODS

The authors define a general hierarchical classification of medical device hazards. This classification is combined with the Trace Intersecting Theory to form a human-machine-environment interaction model. Such a model was applied to the dataset of 2001 to 2017 class I infusion pump recalls extracted from the Food and Drug Administration (FDA) website. This dataset does not include cases involving illegal factors.

RESULTS

The proposed model was used for conducting hazard analysis on 70 cases of class I infusion pump recalls by the FDA. According to the analytical results, an important source of product technical risk was that the infusion pumps did not infuse accurate dosage (ie, over- or underdelivery of fluid). In addition, energy hazard and product component failure were identified as the major hazard form associated with infusion pump use and as the main direct cause for adverse events in the studied cases, respectively.

CONCLUSIONS

The proposed human-machine-environment interaction model, when applied to adverse event data, can help to identify the hazard forms and direct causes of adverse events associated with medical device use.

Changing Smart Pump Vendors: Lessons Learned

Smart infusion pump technology is a mainstay in health care, and the integration and use of those pumps is crucial for patient safety. An institution purchasing smart infusion pumps has the ability to trial the various vendors before purchase, however literature that documents a conversion from one pump to another is lacking. This article describes the conversion from one smart infusion pump platform to another at a government institution and a large multisite facility. The differences in 2 smart infusion pumps are described as well as lessons learned following the conversion in both organizations.

Best Practices for Intrathecal Baclofen Therapy: Screening Test

INTRODUCTION

Intrathecal baclofen (ITB) screening assesses response to a test dose of ITB on spasticity and function and identifies adverse reactions.

METHOD

An expert panel consulted on best practices after conducting an extensive literature search and conducting an online survey.

RESULTS

A successful trial may confirm predetermined goals, which may include improved mobility/positioning, decreased time/improved independence for activities, less home exercise, better wheelchair tolerance, decreased caregiver time, improved sleep, and reduced pain, or may modify goals and expectations. Individuals should not be tested in the presence of active medical issues (e.g., MS exacerbations, active urinary tract infection, nonhealing wounds). Oral antispasmodics can be weaned before trial if a goal is to eliminate them. The standard baclofen test dose is a 50-mcg bolus, 25 mcg in very small children or patients who rely on spasticity for mobility. Patients unresponsive to the standard dose may require 75 mcg or 100 mcg; 24 hours should elapse between bolus doses. Cardiopulmonary parameters should be checked frequently during the first two hours postinjection, and spasticity measures assessed at least twice within four hours. Observation continues until the patient is stable and recovers from hypertonia. Adverse events include spinal headaches, nausea/vomiting, urinary retention, hypotension, seizures, drowsiness/sedation, respiratory depression, and coma. Before implantation, team members must discuss starting dose, drug concentration, delivery mode, pump size and location, and catheter tip placement. Patients/caregivers should understand the commitment necessary for ITB therapy.

CONCLUSIONS

Screening helps identify appropriate candidates for ITB.

A rapid infusion pump driven by micro electromagnetic linear actuation for pre-hospital intravenous fluid administration

A rapid infusion pump with a maximum flow rate of 6 L/h was designed experimentally using a micro electromagnetic linear actuator, and its effectiveness was evaluated by comparing with that of a commercial Power Infuser under preset flow rates of 0.2, 2, and 6 L/h. The flow rate, air detection sensitivity, occlusion response time, quantitative determination of hemolysis, and power consumption of the infusion devices were extensively investigated using statistical analysis methods (p < 0.05). The experimental results revealed that the flow rate of the designed infusion pump was more stable and accurate, and the hemolysis was significantly less than that of the Power Infuser. The air detection sensitivity and the power consumption could be comparable to that of the Power Infuser except the occlusion response time. The favorable performance made the designed infusion pump a potential candidate for applications in pre-hospital fluid administration.

Infusion pump-mediated mechanical hemolysis in pediatric patients

CONTEXT

Hemoglobinuria was observed after packed red blood cell transfusion in a series of patients at our pediatric treatment center. Laboratory testing was suggestive of intravascular hemolysis with no support for an immunohematologic process.

OBJECTIVE

We investigated these adverse events to define a quality improvement plan and to prevent future hemolytic adverse events. Multiple factors were investigated, and the only change identified was the implementation of a new infusion pump (Pump A) that replaced a previous model (Pump B).

DESIGN

In vitro pump analyses, a retrospective review of urinalyses, and prospective urinalysis and nursing surveillances were also performed.

RESULTS

In in vitro analysis of the pumps, irradiated units with higher hematocrit at a low flow rate through Pump A had a greater than thirty-fold increase in free hemoglobin from baseline compared to minimal free hemoglobin changes seen with Pump B. Irradiated units with a lower hematocrit had a minimal change in free hemoglobin from baseline with both Pumps A and B at either low or high flow rate. Subsequently, only units with lower hematocrits were issued for transfusion of pediatric patients, and Pump A was replaced by Pump B in the outpatient unit. Retrospective and prospective surveillances found no additional unexplained cases of gross hemoglobinuria associated with transfusion.

CONCLUSION

The investigation determined that infusion of higher hematocrit units using a specific commercial pump was associated with mechanical hemolysis. The change to units with lower hematocrit through an alternative pump has been an effective corrective action to date.

Syringe drivers: incorrect selection of syringe type from the syringe menu may result in significant errors in drug delivery

There have been many reported adverse incidents due to syringe driver use, most of which have been attributable to human error. In this paper we present a previously unreported, but potentially widespread practice which may result in significant over or under-delivery of medication. Even with the naked eye it is evident that syringes of equal volume have different dimensions and to quantify this we sectioned a range of syringes and measured the inner and outer dimensions. Extensive menus for syringe brand and volumes are available on syringe drivers, offering users greater flexibility. However, this feature also allows users to select an incorrect syringe brand with potential consequences for drug delivery. We measured outputs under all selectable permutations, to determine the degree of fluid delivery variation and discovered inaccuracies in volumes ranging from 10% under-delivery to 24% over-delivery. There is a wide variation in syringe metrics and complex syringe menus may increase errors, resulting in significant under or over-delivery of medication. Availability of more than one brand of syringe in a clinical area increases the risk of adverse drug delivery events. Systems need to be implemented to minimise the risk of adverse events.

Analgesic efficacy and technique of ultrasound-guided suprascapular nerve catheters after shoulder arthroscopy

BACKGROUND

Conventional approaches to brachial plexus blocks may not cover the suprascapular nerve. Accordingly, after shoulder arthroscopy, sensation from the posterior part of the shoulder is commonly spared. Most previous research involving suprascapular nerve blocks described single-injection techniques. However, with the widespread availability and fairly reasonable cost of disposable infusion pumps, continuous catheter techniques provide a more appealing method of prolonging postoperative analgesia.

CASE REPORT

We describe 2 patients who were successfully treated with ultrasound-guided continuous suprascapular nerve catheters. With the patient seated, a high-frequency linear ultrasound probe was used. Both patients experienced excellent pain relief without complications.

CONCLUSION

Continuous suprascapular catheter techniques provide good pain relief and improve postoperative analgesia after shoulder arthroscopy.

Intrathecal baclofen associated with improvement of consciousness disorders in spasticity patients

OBJECTIVE

Intrathecal baclofen (ITB) pump is a therapeutic option for persistent vegetative state and minimal conscious state patients that have associated spasticity. We investigated whether this treatment modality can affect their level of consciousness.

METHOD

In this prospective, open label, observational study, we implanted ITB pumps for the treatment of spasticity in eight patients with disorders of consciousness (vegetative state and minimally conscious state) and we followed them with the Coma Recovery Scale-Revised, the Eastern Cooperative Oncology Group (ECOG) performance scale, and the Modified Ashworth spasticity scale. Baclofen dose and complications also were noted.

RESULTS

The offending pathologies were traumatic brain injury in six, anoxia due to cardiac arrest in one, acute obstructive hydrocephalus in one. Two of the patients showed a marked, persistent improvement that fulfilled the criteria of emergence from minimally conscious state. Two of patients had their ITB pumps prematurely removed because of complications. The ECOG score was 4 for all patients and did not change during the study.

CONCLUSION

ITB might be associated with a significant improvement in the disorder of consciousness of two patients from a total of six that had a chronic ITB treatment.

A feasibility study of bihormonal closed-loop blood glucose control using dual subcutaneous infusion of insulin and glucagon in ambulatory diabetic swine

BACKGROUND

We sought to test the feasibility and efficacy of bihormonal closed-loop blood glucose (BG) control that utilizes subcutaneous (SC) infusion of insulin and glucagon, a model-predictive control algorithm for determining insulin dosing, and a proportional-derivative control algorithm for determining glucagon dosing.

METHODS

Thirteen closed-loop experiments (approximately 7-27 h in length) were conducted in six ambulatory diabetic pigs weighing 26-50 kg. In all experiments, venous BG was sampled through a central line in the vena cava. Efficacy was evaluated in terms of the controller's ability to regulate BG in response to large meal disturbances ( approximately 5 g of carbohydrate per kilogram of body mass per meal) based only on regular frequent venous BG sampling and requiring only the subject's weight for initialization.

RESULTS

Closed-loop results demonstrated successful BG regulation to normoglycemic range, with average insulin-to-carbohydrate ratios between approximately 1:20 and 1:40 U/g. The total insulin bolus doses averaged approximately 6 U for a meal containing approximately 6 g per kilogram body mass. Mean BG values in two 24 h experiments were approximately 142 and approximately 155 mg/dl, with the total daily dose (TDD) of insulin being approximately 0.8-1.0 U per kilogram of body mass and the TDD of glucagon being approximately 0.02-0.05 mg. Results also affirmed the efficacy of SC doses of glucagon in staving off episodic hypoglycemia.

CONCLUSIONS

We demonstrate the feasibility of bihormonal closed-loop BG regulation using a control system that employs SC infusion of insulin and glucagon as governed by an algorithm that reacts only to BG without any feed-forward information regarding carbohydrate consumption or physical activity. As such, this study can reasonably be regarded as the first practical implementation of an artificial endocrine pancreas that has a hormonally derived counterregulatory capability.

Programmable infusion pumps in ICUs: an analysis of corresponding adverse drug events

BACKGROUND

Patients in intensive care units (ICUs) frequently experience adverse drug events involving intravenous medications (IV-ADEs), which are often preventable.

OBJECTIVES

To determine how frequently preventable IV-ADEs in ICUs match the safety features of a programmable infusion pump with safety software ("smart pump") and to suggest potential improvements in smart-pump design.

DESIGN

Using retrospective medical-record review, we examined preventable IV-ADEs in ICUs before and after 2 hospitals replaced conventional pumps with smart pumps. The smart pumps alerted users when programmed to deliver duplicate infusions or continuous-infusion doses outside hospital-defined ranges.

PARTICIPANTS

4,604 critically ill adults at 1 academic and 1 nonacademic hospital.

MEASUREMENTS

Preventable IV-ADEs matching smart-pump features and errors involved in preventable IV-ADEs.

RESULTS

Of 100 preventable IV-ADEs identified, 4 involved errors matching smart-pump features. Two occurred before and 2 after smart-pump implementation. Overall, 29% of preventable IV-ADEs involved overdoses; 37%, failures to monitor for potential problems; and 45%, failures to intervene when problems appeared. Error descriptions suggested that expanding smart pumps' capabilities might enable them to prevent more IV-ADEs.

CONCLUSION

The smart pumps we evaluated are unlikely to reduce preventable IV-ADEs in ICUs because they address only 4% of them. Expanding smart-pump capabilities might prevent more IV-ADEs.

Adaptive closed-loop control provides blood-glucose regulation using dual subcutaneous insulin and glucagon infusion in diabetic Swine

BACKGROUND

In order to stave off deleterious complications of the disease, the ultimate task for people with diabetes is to maintain their blood glucose in euglycemic range. Despite technological advancements, conventional open-loop therapy often results in prolonged hyperglycemia and episodic hypoglycemia, in addition to necessitating carbohydrate counting, frequent glucose monitoring, and drug administration. The logical conclusion in the evolution of exogenous insulin therapy is to develop an automated closed-loop control system.

METHODS

Eleven closed-loop control experiments were conducted in four anesthetized diabetic pigs, with carbohydrate loads simulated by intravenous glucose administration through ear-vein catheters. Type 1 diabetes-like pathology was induced using intravenous administration of cytotoxin streptozotocin. The augmented model-predictive control algorithm accounts for the accumulation of subcutaneous insulin, which is critical in avoiding excessive insulin dosing.

RESULTS

Control results consistently showed successful blood-glucose regulation to euglycemic range within 80-120 minutes after intravenous glucose loads, with no incidence of hypoglycemia. This is consistent with a negative oral glucose tolerance test for diabetes and is the optimal postprandial regulation that can be achieved with subcutaneous insulin administration. Results also demonstrated the potency of subcutaneous glucagon in staving off episodic hypoglycemia and revealed efficacy of the control algorithm in coping with a twofold variation in subject weights, while simultaneously overlooking erratic blood-glucose fluctuations.

CONCLUSIONS

Using an automated adaptive glucose-control system, we show successful blood-glucose regulation in vivo and establish, definitively, the plausibility and practicality of closed-loop blood-glucose control using subcutaneous insulin and glucagon infusion in type 1 diabetes. The control system strikes an intricate balance between tight blood-glucose control and optimal drug consumption, while simultaneously maintaining emphasis on simplicity and reliability.