Refill Procedure Research Articles

Calcification of the pump pouch in patients receiving ITB therapy: A rare complication affecting refill procedure – Analysis of two cases

BackgroundIntrathecal baclofen therapy (ITB) is an effective treatment for reducing spasticity but can be associated with various complications, including infection and implant malfunction. MethodsThis retrospective cohort study analyzed refill reports, complications, and functional outcomes in 40 consecutive patients with intractable spasticity or dystonia undergoing ITB. ResultsAmong the 40 patients, 8 experienced complications, including two cases of calcification of the baclofen pump pouch and surrounding tissue, a rare complication not extensively described in the literature. DiscussionCalcification, in addition to port access difficulties, could lead to drug delivery failure. We hypothesize that calcification may result from microtrauma or needlestick injury to the subcutaneous tissue and muscle fascia. The length of time the pump stays in the pocket could also contribute to favoring this phenomenon. ConclusionAs the number of patients receiving ITB increases, physicians must be aware of potential life-threatening complications. The risk of pouch calcification should be further investigated and considered in managing patients undergoing ITB, as it could significantly impact patient care.

Virtual Reality during Intrathecal Pump Refills in Children: A Case Series.

Virtual reality has proven to be an effective approach to decrease pain in acute settings, both in adults and children. The aim of this study is to evaluate whether virtual reality (VR) could reduce pain during an intrathecal pump refill procedure in children receiving intrathecal drug delivery, compared to a standard refill procedure. This is a three-arm crossover randomized controlled trial, evaluating the effect of VR on pain in children with cerebral palsy undergoing an intrathecal pump refill compared to a standard refill and a refill with distraction (watching a video). Pain was evaluated using the Wong–Baker Faces Scale. Secondary outcomes were procedural pain, fear, state anxiety, the incidence of adverse events and satisfaction. Six children participated in this study, whereby all children underwent the three conditions. Five children indicated an equal of lower pain score during VR, compared to a standard refill. This finding of an equal or lower pain intensity score for the VR condition compared to the control condition was also revealed by the ratings of the parents, physician and the researcher. The influence of VR on anxiety and fear seem to be in line with the influence of watching a video. In terms of satisfaction, all children and parents agreed with the statement that they would like to use VR again for a next refill. Due to the lack of adverse events, the high degree of satisfaction of children with VR and the decreased pain levels after a refill with VR, physicians may aim to explore the implementation of VR during intrathecal pump refill procedures in children in a daily clinical routine care setting.

The Impact of a Music Video on Procedural Pain and State Anxiety

PurposePatients with chronic pain and/or spasticity who have an intrathecal targeted drug delivery (TDD) pump require frequent needle access procedures to refill the pump's medication reservoir. Some patients find the access procedure painful and/or anxiety provoking. The purpose of this study was to determine if a nursing intervention of providing a distraction with a music relaxation video during the pump access procedure would reduce patients’ pain and state anxiety. Design/MethodsIn this longitudinal, pre-test post-test, quasi-experimental design, patients watched a 13-minute calming music video while the nurse performed the needle access procedure. Data collection instruments included a combination of researcher-developed questionnaires, the Defense & Veterans Pain Rating Scale (DVPRS), and the State Trait Anxiety Inventory (STAI). Pain and anxiety were measured pre- and post-pump refill procedures at baseline with no intervention (T1) and at two subsequent pump refills with the music video intervention (T2 and T3). ResultsThe sample consisted of 31 adults with chronic pain (n = 28) or spasticity (n = 3). All participants had an implanted pump for at least six months. Specialty trained nurses refilled the participants’ pump in their home. The findings support the use of a music video as an effective intervention for reducing participants’ perception of pain and anxiety during the pump refill procedure. Neither pre-test pain nor pre-test anxiety scores differed across time. Post-test mean pain scores decreased consistently across time (T1 = 5.55, T2 = 4.42, T3 = 4.23; P = .002). Post-test anxiety scores showed a significant decrease (P <.05) between T1 (M = 37.87) and T2 (M = 30.94) which was not sustained at T3 (M = 35.68, P = .284). Overall, the majority of participants indicated liking the music video intervention. They also expressed interest in using the intervention for future refill procedures or other stressful situations. ConclusionsThe music video was effective in producing a sustained reduction over time of participants’ pain during the pump refill procedures; it was most effective in initially reducing participants’ state anxiety at the initial intervention visit; however, it did not demonstrate a progressively sustained effect. Participants’ opinions about the music video experience were positive.

Accuracy of Template Versus Ultrasound Identification of the Reservoir Access Port of Intrathecal Drug Delivery System

Precise localization of the center of the reservoir access port (RAP) of intrathecal pump is a crucial step to ensure a safe refill procedure. In difficult refill cases, ultrasound guidance has been reported useful. Being more expensive and time-consuming, the purpose of the study was therefore to identify situations in which sonographic localization is more accurate than the template method, in order to restrict its use to these defined conditions. The RAP was localized using the template provided by the manufacturer and by ultrasound guidance. The distance between the two points was measured. A distance superior to 3.5 mm, corresponding to the radius of the silicone septum of the RAP, was considered a clinically significant deviation. During the study period, 22 patients underwent a total of 81 refill procedures. No significant correlation was found between the distance between the two points and age, height, weight, body mass index (BMI) or abdominal perimeter. The correlation was significant between distance and pump's depth. According to the ROC curve, the sensitivity of ultrasound identification of the RAP was 69.2% and the specificity 83.3% when the pump was implanted at a depth of 10 mm. Our results are comparable to these published in the literature, pointing the usefulness of ultrasound for refill of deeply implanted pumps. Our study provides an additional element by specifying the depth from which the ultrasound seems to be superior to template. Poor accuracy in RAP identification of intrathecal pump can lead to life-threatening complications. The results of our study suggest that the localization of recessed-RAP can be improved by ultrasound in cases of pump implanted deeper than 10 mm. For more superficially implanted devices, the template method seems to be as accurate as ultrasound.

Refill Port Identification of Intrathecal Drug Delivery System Devices With a Raised Fill Port

The aim of this study was to assess the accuracy of the manual identification of the reservoir fill port (RFP) for refill of intrathecal drug delivery systems (IDDSs) with a raised RFP on the pump surface (raised-RFP-IDDSs), and compare this to previously reported data of patients with IDDSs with a recessed RFP (recessed-RFP-IDDSs). Nineteen patients underwent 2 IDDS refills for the treatment of noncancer pain or spasticity. The primary endpoint of this prospective observational study was the deviation between the needle insertion point and the RFP center, quantified by fluoroscopic visualization. A distance surpassing that between the center and the margin of the RFP of 4mm was considered a clinically relevant deviation. The results were compared with previously reported data of a patient cohort with recessed-RFP-IDDSs, and the differences were tested using Student's t-test. The mean deviation from the RFP center was 4.9mm (standard deviation=3.7). The RFP identification accuracy deviated more than the clinically relevant difference in 17 out of 35 instances (48.6%). The number of attempts and median procedural time was significantly correlated to the needle deviation. The mean deviations in the raised-RFP-IDDS cohort were consistently lower compared to the recessed-RFP-IDDS cohort (first refill procedure 4.0 vs. 8.5, P<0.001; second procedure 5.9 vs. 8.1, P=0.074). The results of this study suggest that the manual localization of the RFP for raised-RFP-IDDSs is moderately accurate, and more accurate if compared to previously published accuracy of the template-guided technique for recessed-RFP-IDDSs.

Ease of Fill Port Access During the Ultrasound-Guided vs. the Blind Refill Technique of Intrathecal Drug Delivery Systems With a Raised Septum, a Prospective Comparison Study

The localization of the reservoir fill port of Intrathecal Drug Delivery Devices (IDDS) can be difficult. The purpose of this study was to assess the ease of fill port access during the ultrasound-guided refill technique compared to the blind refill technique in IDDSs with a raised septum on the pump surface. Written informed consent was obtained from 19 adult patients undergoing regular refills of their Raised Septum IDDSs (RS-IDDSs). The primary outcome of this single center prospective comparison study was the number of attempts to enter the reservoir fill port with the needle comparing the ultrasound-guided technique vs. the blind technique. The number of skin punctures per refill procedure and time to enter the reservoir fill port was secondary outcomes. For between group comparisons the Friedman test for repeated measures on ranks was used. One hundred and eleven refill procedures were assessed in 19 patients over a period of 24 months. The median number of attempts to enter the reservoir fill port with the needle differed significantly between the ultrasound-guided technique and the blind technique (4 [IQR: 1-6] vs. 1 [IQR: 1-3], p = 0.018), in favor of the blind technique. The median time to enter the reservoir fill port differed significantly between the ultrasound-guided technique and the blind technique (58 sec [IQR: 38-94] vs. 22 sec [IQR: 16-40], p < 0.001). The results of this study suggest that for a RS-IDDS the blind refill technique needs significantly less attempts to enter the reservoir fill port than the US-guided refill technique.

Intrathecal Pump Refills, Pocket Fills, and Symptoms of Drug Overdose: A Prospective, Observational Study Comparing the Injected Drug Volume vs. the Drug Volume Effectively Measured Inside the Pump

One complication associated with the refill procedure of intrathecal drug delivery systems (IDDSs) include a "pocket fill," which is the inadvertent injection of the drug into the subcutaneous space surrounding the pump. The purpose of our study was to assess the mean volume discrepancy between the injected and the effective drug volume inside the IDDS reservoir after refills that did not lead to signs of overdose and to record at which volume discrepancy symptoms of overdose were noticed. After 221 refill procedures performed in 19 adult patients, drug volume inside the reservoir was assessed with a fill level sensor, and the volume discrepancy between injected and measured volume was recorded. Symptoms of overdose were monitored. For between group comparisons the Mann-Whitney U test was used, using a p-value of <0.05 to indicate statistical significance. The median volume discrepancy in the 20 mL IDDSs was 0.40 mL (IQR: 0.18-0.61; 10th p: 0.0; 90th p: 0.74) whereas in the 40 mL IDDSs the median volume discrepancy was 1.3 mL (IQR: 1.06-1.74; 10th p: 0.81; 90th p: 2.2). Symptoms of overdose were observed after 6 out of the 221 refill procedures. Volumes at which the symptoms of overdose arose were between 1.15 and 4.5 mL in 20 mL IDDSs and between 2.08 and 4.88 mL in 40 mL IDDSs. A volume discrepancy of >1 mL in 20 mL IDDSs and of >2 mL in 40 mL IDDSs after refill should be regarded as potentially consequential with regard to risk of overdose possibly caused by a pocket fill. In case of potentially consequential volume discrepancies, hospitalization and monitoring is recommended to preclude late overdose symptoms outside the hospital.

Training for the Intraspinal Drug Delivery System Reservoir Refill Procedure Highly Variable: A Nationwide Survey of Health Care Professionals

This study describes the training, experience with pocket fills, and life-long learning behaviors in a national sample of health care professionals who perform the reservoir refill procedure and compares results with intraspinal drug delivery morbidity and mortality clinical practice guidelines to demonstrate the need for standardized training. Using a cross-sectional, descriptive design and a 23-item questionnaire administered via social media, 65 health care professionals who performed the reservoir refill procedure within the last year were surveyed. Descriptive and inferential statistics were used for analysis. Our results showed: 1) training varied widely and lacked supervision and mentoring for the inexperienced clinician, 2) the highest number of pocket fills was reported by the most experienced clinicians, and 3) there was limited participation in professional meetings where intraspinal therapy is discussed. The use of intraspinal drug delivery clinical practice guidelines significantly increased in current practice compared to use during training. Training for the reservoir refill procedure was highly variable, inconsistent with intraspinal drug delivery clinical practice guidelines' training recommendations with a high number of pocket fills, and low participation in national intraspinal drug delivery meetings. Standardized training is needed to reduce variability and minimize the risk for human error during the reservoir refill procedure.

The Role of Microfat Grafting in Facial Contouring.

Congenital hypoplasia of facial bones has traditionally been treated by orthognathic surgery. However, the inherent invasiveness of orthognathic surgery often leads to a high complication rate. Facial fat grafting could be a less invasive method to correct facial deformities. The aim of this study was to evaluate the results of microfat grafting for facial contouring. This retrospective chart review evaluated 166 patients who were treated with microfat grafting for maxillary and/or mandibular hypoplasia. Pretreatment and posttreatment photographs were compared regarding improvement of facial contour, and complications were recorded. The follow-up period ranged from 4 months to 10 years (mean, 2 years 7 months). Thirty-eight percent of the patients had a refill procedure 6 or more months after the first procedure. A majority of the evaluated patients stated that they benefited from the microfat grafting, with ratings of excellent (50%), sufficient (48%), and poor (2%). Complications included visible fat lobules under the lower eyelid skin (7%), which was seen during the first 4 years and was resolved by changing the injection cannulae and technique, and fat resorption, which was seen in all patients, with a clinical range from ±15% in the immobile malar area and chin region to ±50% in the mobile lip area. Facial microfat grafting is a valuable alternative to more complicated advancement osetotomies being performed in patients solely for aesthetic reasons. The low morbidity and rapid recovery make facial microfat grafting a welcome tool in the armamentarium of the modern facial aesthetic surgeon.

A coupled lattice Boltzmann-finite element approach for two-dimensional fluid–structure interaction

In this paper, a systematic approach to couple the lattice Boltzmann and the finite element methods is presented for fluid–structure interaction problems. In particular, elastic structures and weakly compressible viscous fluids are considered. Three partitioned coupling strategies are proposed and the accuracy and convergence properties of the resultant algorithms are numerically investigated together with their computational efficiency. The corotational formulation is adopted to account for structure large displacements. The Time Discontinuous Galerkin method is used as time integration scheme for structure dynamics. The advantages over standard Newmark time integration schemes are discussed. In the lattice Boltzmann solver, an accurate curved boundary condition is implemented in order to properly define the structure position. In addition, moving boundaries are treated by an effective refill procedure.

Intravenous Treprostinil Delivered by the Implantable Pump Lenus Pro®: A Innovative “Surgical” Approach to Management of PAH

Purpose Continuous application of parenteral prostanoids with external pump systems is associated with frequent side effects such as infusion site pain with subcutaneous (s.c.) and rare but possibly life-threatening catheter related infections with intravenous (i.v.) administration. Lenus Pro ® implantable infusion pump was developed to overcome the drawbacks of s.c. administration. Methods and Materials Between September 2010 and October 2012 20 patients underwent implantation at our center. All patients had experienced significant clinical benefits with s.c. Treprostinil but reported serious site pain. All implantations were performed under general anesthesia. Preoperatively single-shot antibiotic prophylaxis was given. After a catheter was placed in the subclavian or cephalic vein, the pump pocket was prepared in the abdominal wall. Lenus Pro® pump was filled intraoperatively, placed in the pump pocket and fixed to the fascia. A catheter was tunneled under the breast tissue and connected with the central venous access by means of a titan connector. No intraoperative complications occurred; postoperatively three patients developed mild seroma. During follow-up, no other complications were observed. More than 300 refill procedures have been performed without any complications. Control of the reflow volume at every refill procedure revealed accurate and constant flow rate of Lenus Pro ® in all patients. Results Parenteral prostanoids are a cornerstone in the treatment of PAH. I.v. Treprostinil administered by Lenus Pro® was safe and effective in our study population, during more than 330 patient-months of treatment there were no pump or catheter related complications, especially no infections. No refill complications were observed. The absence of infusion related side effects is associated with an increase in quality of life, filling intervals of 28 days ensure optimal patient management and compliance. Conclusions We consider this new treatment option a milestone achievement in prostanoid therapy and management of PA.

Aberrant Intrathecal Pump Refill

Intrathecal drug delivery systems are an effective and increasingly common pain treatment modality for certain patient populations. Pumps are surgically inserted in a subcutaneous abdominal pocket and refilled with highly concentrated medication at regular intervals. Inadvertent injection of medication outside the pump is a known complication of the refill procedure. We describe the injection of hydromorphone into the pump's surrounding subcutaneous pocket, subsequent opioid overdose, and the novel application of ultrasound to visualize and aspirate the subcutaneous drug. Ultrasonography can be used as an effective modality for rapid diagnosis and treatment of an accidental pocket fill.

Transverse harmonic oscillations of laminae in viscous fluids: a lattice Boltzmann study

In this paper, we use the lattice Boltzmann method with the Bhatnagar-Gross-Krook linear collision operator to study the flow physics induced by a rigid lamina undergoing moderately large harmonic oscillations in a viscous fluid. We propose a refill procedure for the hydrodynamic quantities in the lattice sites that are in the vicinity of the oscillating lamina. The numerically estimated flow field is used to compute the complex hydrodynamic function that describes the added mass and hydrodynamic damping experienced by the lamina. Results of the numerical simulations are validated against theoretical predictions for small amplitude vibrations and experimental and numerical findings for moderately large oscillations.

The Implantable Peritoneal Pump—A Patient's Perspective

A participant in a study of implantable insulin pump therapy recounts his experiences with on-and-off use of the pump over the past 18 years. Christopher Witkowski, 55, first had a pump implanted in 1990. Despite occasional difficulties over the years, Witkowski reports that his overall experience has been extremely positive. With delivery of insulin directly into the peritoneal cavity, he feels better, has more flexibility in eating, and experiences fewer insulin reactions. Witkowski expresses disappointment that the manufacturer of the pump, Medtronic, no longer plans to seek Food and Drug Administration approval for this therapy. Witkowski expresses his hope that research on the device will continue, believing that this therapy could be of benefit to millions of diabetes patients. This article is accompanied by a detailed description of the pump refill procedure by Dr. Christopher Saudek of Johns Hopkins University, current leader of the ongoing research study.

Chronic Intrathecal Baclofen Infusion for Spasticity: Relationship between Pump and Host

Twenty patients with chronic intractable spinal spasticity were implanted with a totally implantable programmable pump for intrathecal administration of baclofen. The objective of this study was to evaluate the relationship between pump and the host. Clinical efficacy of the therapy was evaluated by the Ashworth Scale, the Spasms Frequency Scale, and the Functional Independence Measure (FIM) motor scores. All patients were asked to reply to 10 questions regarding discomfort of their refills, the ease of rehabilitation after therapy, their fear of pump failure and onset of alarm signals, their discomfort due to a metallic foreign body (the pump), the attitude of their relatives and other persons regarding their pump system, whether they would undergo this therapy again, and whether, in the absence of public health insurance, whether they would be willing to pay for their pump and therapy. The Ashworth scale, the Spasms Frequency Scale, and the FIM motor score showed a significant improvement in all patients after the onset of therapy with baclofen. The refill procedure was not a problem in all patients while four patients (20%) considered the number of refills "uncomfortable." Rehabilitation was no problem after the pump was implanted in all patients, 10 patients (50%) feared pump failure, while six patients (30%) feared their alarm signals. Three patients (15%) had some discomfort from their pumps rubbing against their belts; two patients (10%) stated that other people were aware of their pumps; all but two patients (10%) were ready to have their implants again; three patients (15%) would pay for the pump in case of absence of public health insurance for the therapy. We conclude that the implant of pumps for chronic intrathecal baclofen infusion is, today, a known effective procedure. Refill of the pump system was not a problem in our patient population, while the number of refills did cause some discomfort in some patients. It was shown by our study that the pump did facilitate rehabilitation in our patients, and a certain degree of dependence on the pump did exist. Fifty percent of the patients were afraid of pump failure and 30% were afraid of their alarm signals going off. The fact that most patients would undergo this therapy again and some would even pay for it directly in the absence of public insurance for the therapy were indices of patient satisfaction with the procedure. Because this was a small study, we believe that larger studies are necessary to corroborate our findings.