Assessment of efficacy of postinfusion tubing flushing in reducing risk of cytotoxic contamination.

PURPOSE: Infusion of cytotoxic drugs carries the risk of occupational exposure of healthcare workers. Since disconnecting an infusion line is a source of contamination, flushing of tubing after infusion of cytotoxic agents is recommended, but the optimal volume of rinsing solution is unknown. The objective of this study was to assess whether postinfusion line flushing completely eliminates cytotoxics. METHODS: Infusions were simulated with 3 cytotoxics (gemcitabine, cytarabine, and paclitaxel) diluted in 5% dextrose injection or 0.9% sodium chloride injection in 250-mL infusion bags. Infusion lines were flushed using 5% dextrose injection or 0.9% sodium chloride solution at 2 different flow rates. The remaining concentration of cytotoxics in the infusion line was measured by a validated high-performance liquid chromatography (HPLC) method after passage of every 10 mL of flushing volume until a total of 100 mL had been flushed through. RESULTS: All cytotoxics remained detectable even after line flushing with 80 mL of flushing solution (a volume 3-fold greater than the dead space volume within the infusion set). Gemcitabine and cytarabine were still quantifiable via HPLC even after flushing with 100 mL of solution. Efficacy of flushing was influenced by the lipophilicity of drugs but not by either the flushing solvent used or the flushing flow rate. After 2-fold dead space volume flushing, the estimated amount of drug remaining in the infusion set was within 0.19% to 0.56% of the prescribed dose for all 3 cytotoxics evaluated. CONCLUSION: Complete elimination of cytotoxics from an infusion line is an unrealistic objective. Two-fold dead space volume flushing could be considered optimal in terms of administered dose but not from an environmental contamination point of view. Even when flushed, the infusion set should still be considered a source of cytotoxic contamination.

[Perioperative infusion therapy in children : Are infusion sets with precision flow regulators suitable for pediatric anesthesia?] / Perioperative Infusionstherapie im Kindesalter : Eignen sich Infusionssysteme mit Laufratenbeschränkung für die Kinderanästhesie?

BACKGROUND: Infusion sets with precision flow regulators are frequently used in children undergoing surgery in order to control the perioperative administration of fluids. There are no data about the safety and accuracy of these infusion sets. A study was therefore conducted to compare adjusted and actual flow rates of three different infusion sets with precision flow regulators under standardized conditions. METHODS: The study evaluated three different infusion sets with precision flow regulators each at two different static levels. The actual flow rates of 5 infusions were recorded each time for adjusted flow rates of 50 ml/h, 100 ml/h, 150 ml/h, 200 ml/h and 250 ml/h over 1 h. Statistical analysis was performed with Excel (Excel, Microsoft Corporation, Redmond, WA, USA) and SOFA (Paton-Simpson and Associates Ltd., USA). The results are presented as means (standard deviation). RESULTS: For the adjusted flow rates of 50, 100, 150, 200 and 250 ml/h, actual flow rates were 107 (5.3), 174.8 (6.5), 255.8 (10.2), 312.4 (15.7) and 362.6 (20.2) ml/h for the Frekadrop® infusion set at a static level of 128 cm and 83.8 (4.4), 147.8 (5.5), 197 (12.4), 257.2 (4.97) and 311.6 (17.9) ml/h at a static level of 100 cm, respectively. For the Exadrop® infusion set actual flow rates were 88.6 (6.9), 131.2 (14.1), 224.4 (14.1), 296.6 (27.6) and 330.4 (22.4) ml/h at a static level of 128 cm and 54 (4), 82.4 (10.2), 138.8 (15.7), 209.4 (36.8) and 249 (12) ml/h at a static level of 76 cm, respectively. For the D-Flo infusion set actual flow rates were 95.6 (2.8), 167.6 (29), 217.8 (9.9), 281.6 (10.6) and 396.8 (37.5) ml/h at a static level of 128 cm and 69.2 (4.4), 110.2 (12.6), 169.2 (6), 205.2 (14) and 243 (15.9) ml/h at a static level of 80 cm, respectively. CONCLUSION: The actual flow rates differed considerably from the adjusted flow rates in the evaluated infusion sets. The flow rates substantially depended on the static level of the infusion. First and foremost, regulation of the administered infusion volume does not seem to be reliable when using an infusion set with a precision flow regulator.

Programmed intermittent bolus infusion versus continuous infusion of 0.2% levobupivacaine after ultrasound-guided thoracic paravertebral block for video-assisted thoracoscopic surgery: A randomised controlled trial.

BACKGROUND: The analgesic benefits of programmed intermittent bolus infusion for thoracic paravertebral block remain unknown. OBJECTIVE: The aim of this study was to compare the analgesia from intermittent bolus infusion with that of a continuous infusion after thoracic paravertebral block. DESIGN: A randomised controlled study. SETTING: A single centre between December 2016 and November 2017. Seventy patients scheduled for video-assisted thoracoscopic surgery were included in the study. INTERVENTION(S): Patients were randomly assigned to receive 0.2% levobupivacaine via continuous infusion (5 ml h, continuous group) or programmed intermittent bolus infusion (15 ml every 3 h, bolus group) after an initial 15-ml bolus injection of 0.2% levobupivacaine. MAIN OUTCOME MEASURES: The main outcome was the amount of rescue fentanyl (per kg of body weight) consumed within 24 h after surgery. Secondary outcomes were postoperative pain scores, plasma levobupivacaine concentrations and the number of dermatomes anaesthetised. RESULTS: There was no significant difference between the continuous and bolus groups in the postoperative consumption of fentanyl (median [interquartile range] 5.5 [4 to 9.5] µg kg versus 6 [3.5 to 9] µg kg respectively, P = 0.45) and postoperative pain scores within 24 h. At 20 h after initiating the infusions, there was no statistically significant difference between the two groups in terms of the plasma levobupivacaine concentration. The number of dermatomes anaesthetised to pinprick and cold testing was significantly greater in the bolus group. CONCLUSION: Our findings suggest that postoperative pain and opioid usage are similar with either programmed intermittent bolus infusion or continuous infusion after thoracic paravertebral block. Programmed intermittent bolus infusion provides a wider sensory blockade and could benefit patients requiring a wider extent of anaesthesia. TRIAL REGISTRATION: UMIN Clinical Trials Registry (UMIN-CTR; URL: http://umin.ac.jp/ctr/, ID: UMIN000023378).

Twenty-five-gauge trocar anterior chamber maintainer: New device for infusion.

The technique, feasibility, and results of a new 25-gauge trocar-anterior chamber maintainer (ACM) designed for maintaining intraoperative fluid infusion is described in this prospective interventional analysis. The 25-gauge trocar-ACM with an overall length of the trocar blade of 6.0 mm, cannula length of 4.0 mm, and the cannula tip beveled at 45 degrees to the base was designed and used in all the cases. The dimensions of the sclerotomy wound that comprised of the internal ostium, external ostium, wound length, and the time interval for wound apposition in the postoperative period was analyzed by spectral-domain anterior segment optical coherence tomography.

Interventional MRI-guided local delivery of agents into swine bile duct walls using MR-compatible needle-integrated balloon catheter system.

The purpose of this study was to investigate the feasibility of interventional MRI-guided local agent delivery into pig common bile duct (CBD) walls using a newly designed MR-compatible, needle-integrated balloon catheter system. We first designed a needle-integrated balloon catheter system that comprised of a 22 G MR-compatible Chiba biopsy needle and a conventional 12 mm × 2 cm balloon catheter. Under fluoroscopy guidance, a custom needle-balloon system was positioned in the target CBD via a transcholecystic access. T1-weighted MRI was used to localize and reposition the needle-balloon system in the target. A 0.5 mL mixture of motexafin gadolinium (MGd) and trypan blue dye as well as 5-fluorouracil was delivered into the CBD wall through the needle-balloon system. Post-infusion T1-weighted MRI was obtained and contrast-to-noise ratios (CNRs) of CBD walls of pre- and post-MGd-blue infusions were compared by a paired t-test. In addition, post-infusion x-ray cholangiography was achieved to evaluate the potential injuries of CBDs by the needle-balloon system. Subsequent histologic analysis was performed to correlate and confirm the imaging findings. A post-infusion cholangiogram did not show any extravasation of contrast agent, indicating no procedure-related damage to the CBDs. MRI demonstrated clear enhancement of the target bile duct walls infused with MGd-trypan blue dye with average penetration depth of 4.7 ± 1.2 mm and an average MGd perfusion length of 21 ± 1.5 mm in the bile ducts and their surrounding tissues. The average CNR of the post-infusion bile ducts was significant higher than that of the pre-infusion bile ducts (110.6 ± 22 versus 5.7 ± 2.8, p < 0.0001). Histology depicted the blue dye staining and red fluorescence of MGd through the target CBD walls, which was well correlated with the imaging findings. It is feasible to use the new MR-compatible, needle-integrated balloon catheter system for intrabiliary local agent delivery into CBD walls under MRI guidance, which may open new avenues for efficient management of pancreatobiliary malignancies using MR-guided interventional oncology.

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy: a case report.

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) is a complex procedure used for the treatment of various types of cancer. Specifically, HIPEC has shown success where treatment failure sites (metastases) thrive. A classic example of one such area is the peritoneal surface, which remains a prominent failure site for patients with gynecologic and gastrointestinal cancer. Traditionally, most patients with advanced stages of cancer have undergone palliative procedures as part of their treatment modality or had no surgery at all. With the advent of cytoreductive surgery with HIPEC, patients with peritoneal cancer have shown increased survival rates. Anesthetic complications are common during this procedure with disturbances in hemodynamics, coagulation, and respiratory gas exchange. A knowledge of what to anticipate anesthetically will guide the practitioner to achieve successful management during and after the case. In this case report, a 71-year-old woman was treated for stage Ill peritoneal and ovarian cancer by cytoreductive surgery with HIPEC.

In vivo performance of a microfabricated catheter for intraparenchymal delivery.

BACKGROUND: Convection-enhanced delivery (CED) is currently the only effective clinical technique to deliver biological therapeutic agents that would otherwise not cross the blood-brain barrier. Despite the promise of CED, several technical problems have limited its effectiveness. NEW METHOD: Brain infusions into a large mammal (pig) were performed with a catheter that was fabricated using micro-electro-mechanical systems (MEMS) technology (Olbricht et al., 2010). The performance of the catheter was evaluated for infusions at increasing infusion rates. Magnetic resonance (MR) images were acquired in real time to examine the distribution of infused tracers in the parenchyma. RESULTS: Both backflow and the distribution of CED of infusates into a variety of cytoarchitectures in porcine brain were quantified. Concentration profiles were determined for several MR contrast reagents as well as a fluorescent dye that are the sizes of small molecules, therapeutic proteins and an adeno-associated virus (AAV). The reagents can serve as surrogates for assessing the convective distribution of active molecules. Infusion rates up to 20µL/min were attained without evidence of backflow along the catheter. COMPARISON WITH EXISTING METHODS: The device performed well in terms of both backflow and infusion, superior to that of many studies reported in the literature on other catheters. All infused molecules had comparable ratios of distribution to infusion volumes. CONCLUSIONS: The catheter described in this report appears able to target tissue structures with precision, deliver therapeutics at high infusion rates, and resist backflow that can compromise the efficacy of CED therapy. The technology allows development of "smart" catheters for future applications.

Microbubble transmission during cardiotomy infusion of a hardshell venous reservoir with integrated cardiotomy versus a softshell venous reservoir with separated cardiotomy: an in vitro comparison.

An important mechanism for postoperative cognitive impairment after cardiac surgery using cardiopulmonary bypass (CPB) is microemboli. One component of the CPB circuit-the cardiotomy-is a major source of gaseous microemboli because it aspirates significant volumes of air with blood from the operative field and intracardiac chambers. Cardiotomies are either integrated within an open hardshell venous reservoir (IC-HSVR) or are a separate canister attached to a softshell collapsible venous reservoir bag (SC-SSVR). The purpose of this study was to compare the Medtronic IC-HSVR (Affinity NT CVR) with Medtronic's SC-SSVR (CB 1351, CBMVR 1600) in terms of relative microbubble transmission during cardiotomy infusion. A recirculating in vitro circuit primed with blood was used to compare the two cardiotomy-reservoir systems with the venous reservoir in the SC-SSVR further assessed in a fully closed or partially open state (SC-SSVR-closed; SC-SSVR-open). Microbubbles were detected using a GAMPT BC100 Doppler system in the outflow line of the venous reservoir. Measurements were taken before (baseline) and after aerated prime was pumped into the cardiotomy while altering pump flow rates (3 L/min; 5 L/min) and reservoir prime volumes (400 mL; 900 mL). Infusing cardiotomy blood into the venous reservoir was associated with an increase in microbubbles and bubble volume transmitted by both cardiotomy-reservoir systems with the magnitude rising with reduced prime volumes. The effect was markedly greater with the IC-HSVR. The IC-HSVR also transmitted larger bubbles, particularly with reduced prime volumes. There was no significant difference in microbubble transmission seen between the SC-SSVR-closed and SC-SSVR-open. The SC-SSVR transmits fewer microbubbles than the IC-HSVR during cardiotomy infusion and should be considered as the preferential system. Because both cardiotomy-reservoir systems transmitted microbubbles during cardiotomy infusion, particularly at the lower venous reservoir volume, it is important to use strategies to minimize cardiotomy microbubble infusion.

[Cytoreductive surgery and HIPEC: a curative strategy for primary and secondary peritoneal tumors]. / Radikale zytoreduktive Chirurgie mit hyperthermer intraperitonealer Chemotherapie (HIPEC) als kurativer Ansatz zur Behandlung primärer und sekundärer Peritonealtumore.

In patients with peritoneal carcinomatosis, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) offers a chance for long term survival in well selected patients. During cytoreductive surgery, all macroscopically visible tumors needs to be resected before HIPEC is performed in the same procedure. The aim of HIPEC is eradication of microscopic tumor cells after radical surgery. Perioperative morbidity and mortality are comparable with other major surgical procedures. Patients with peritoneal carcinomatosis from tumors of the appendix, the colon or primary peritoneal mesothelioma are currently recommended for evaluation of CRS/HIPEC in an interdisciplinary setting.

Chez les malades présentant une carcinomatose péritonéale, la chirurgie cytoréductive et la chimiothérapie intrapéritonéale hyperthermique offrent une chance de survie prolongée dans certains cas bien sélectionnés. Au cours de la chirurgie cytoreductive, toute la tumeur visible macroscopiquement doit être réséquée avant que ne soit effectuée, dans la même procédure, à la chimiothérapie intrapéritonéale hyperthermique. Le but de cette dernière est d'éradiquer toutes les cellules microscopiques de la tumeur après la chirurgie radicale. La morbidité et la mortalité périopératoires sont comparables à celles d'autres interventions chirurgicales majeures. La chirurgie cytoréductive et la chimiothérapie intrapéritonéale hyperthermique font partie de la stratégie de traitement multimodale chez les patients ayant des tumeurs limitées à la surface du péritoine. Il est recommandé aujourd'hui d'envisager un traitement par chirurgie cytoréductive et chimiothérapie intrapéritonéale hyperthermique chez les patients présentant une carcinomatose péritonéale avec pour origine l'appendice, le côlon ou le mésothéliome péritonéal primaire.

Description of a novel approach for intraperitoneal drug delivery and the related device.

BACKGROUND: Two significant limitations of intraperitoneal drug therapy are limited drug distribution and poor penetration into peritoneal nodules. A possible solution is the application of the so-called "therapeutic pneumoperitoneum," taking advantage of the gaseous nature and the pressure of capnoperitoneum during laparoscopy. Our objective was to develop a device able to apply such therapeutic pneumoperitoneum. METHODS: The technology presented here is a spraying device and can be introduced through a trocar. It is driven by mechanical pressure and consists of an injector, a line, and a nozzle. An in vivo experimental study was performed in five pigs. A transvaginal cholecystectomy was performed. At the end of the procedure, a standard dose of methylene blue was sprayed/infused into the abdominal cavity for 30 min (4 test animals w/therapeutic pneumoperitoneum (12 mmHg CO(2)) and 1 control animal w/conventional lavage (2 l intra-abdominal volume with extracorporeal circulation)). At the end of the procedure, all animals were autopsied and the peritoneum was analyzed. Outcome criteria were: (1) drug distribution (as assessed by the stained peritoneal surface at autopsy), and (2) diffusion into the peritoneum (presence or not of macroscopic staining of the outer aspect of the peritoneum immediately after surgery). RESULTS: Stained peritoneal surface was larger after aerosol application compared with peritoneal lavage, and staining more intense. Hidden peritoneal surfaces and the anterior abdominal wall were stained only in the aerosol group. In contrast to peritoneal lavage, the outer aspect of peritoneal membrane was immediately stained after pressurized spraying. CONCLUSIONS: This device and the related approach significantly improve both distribution and penetration of a test substance into the peritoneal cavity in a large animal model. This might be a significant progress in treating intraperitoneal disease, in particular peritoneal carcinomatosis.

Ports and complications for intraperitoneal chemotherapy delivery.

Intraperitoneal access ports are essential to the delivery of chemotherapy agents into the peritoneal cavity of women with ovarian cancer, but their malfunction and adverse effects are frequently responsible for the failure to complete planned therapy. Complications, such as obstruction of the catheter, infection, leakage, rotation, retraction, and pain, together with bowel and vaginal perforation, cause delays in treatment, patient suffering and the expenditure of medical resources. A wide variety of ports have been used, including vascular access devices and intraperitoneal access devices. This paper reviews the development and use of ports for intraperitoneal chemotherapy, their complications and reported methods of prevention.

Technique of intraperitoneal chemotherapy using veress needle in patients with ovarian cancer.

Adjuvant intraperitoneal chemotherapy in ovarian cancer has shown improved survival but limited by catheter-related complications. We present a technique of Veress needle use for intraperitoneal instillation of chemotherapy for 220 procedures in 43 patients with minimal adverse effects all managed conservatively. Our unique technique of paclitaxel instillation is described.

Transtracheal aspiration and infusion in the horse.

Transtracheal access enables researchers to obtain diagnostic samples from or infuse materials into the lower respiratory tract. This column describes transtracheal aspiration and infusion of horses.

Incorrect key presses may cause Nutricia Flocare Infinity series enteral feeding pumps to appear to be infusing even though an occlusion exists.

If users of Nutricia Flocare Infinity or Flocare Infinity+ feeding pumps press the unit's Fill Set key while attempting to address an occlusion alarm, the unit's display may indicate normal device operation even though the unit is not delivering feeding solution. Failure to deliver solution may result in hypoglycemia, which can have severe outcomes for patients who have difficulty maintaining their blood sugar levels. Flocare users should become familiar with the issue and with the guidance offered in the products' instructions for use.

In vitro evaluation of hydraulic characteristics of prototype implantable intrathecal infusion pump.

The use of the intrathecal infusion pump for therapeutic treatment and pain management is increasing. For example, one such application is the pain treatment of cancer patients suffering from severe chronic pain, where all other treatment methods have failed. This method is gaining popularity because of its high cure effect with low dosage. In this study, we developed a prototype implantable intrathecal infusion pump and evaluated its mechanical and hydraulic characteristics in vitro to determine how its performance varied under different environmental conditions. The data are reported as means (standard deviations). In the experiments, the prototype pump could control the micro-scale infusion amount, and its performance was affected by ambient temperature and pressure conditions. In a temperature change test, at a constant pressure of 1.0 atm, the minimal amounts of a bolus were 4.44 (1.07), 5.06 (1.17), and 5.54 (0.90) uL for the temperature of 27.5, 36.5, and 42°C, respectively. In a pressure change test, at a constant temperature of 36.5°C, the minimal amounts of a bolus were 5.06 (1.17), 5.94 (0.67), and 6.13 (0.39) uL for pressures of 1.0, 0.9 and 0.8 atm, respectively. These experimental results demonstrate the possibility of using the prototype pump as an implantable microvolumetric infusion device. However, this prototype pump will have to undergo further design enhancement before being clinically feasible for such an application.

Surgical aspects and complications of continuous intraperitoneal insulin infusion with an implantable pump.

PURPOSE: Continuous intraperitoneal insulin infusion (CIPII) with an implantable pump is safe and effective in selected subjects with diabetes. Our aim was to assess surgical experience and complications with CIPII. METHODS: We performed a retrospective longitudinal observational cohort study of patients that started with CIPII from 1990 to 2006. Operation free period and complication rate were compared between patients initiating CIPII before 2000 and from 2000 onwards. RESULTS: In 63 patients, 166 re-operations were performed during 381 patient-years. Re-operations were pump replacement due to end-of-battery life (47%), laparoscopic catheter-related procedures (29%) and other interventions (24%). Median operation free period increased from 21 to 78 months from 2000 onwards (p = 0.039). Nineteen percent of patients developed complications. No operation-related mortality was reported. CONCLUSIONS: Increased experience together with technical improvements has led to an increase of the operation free period. The absence of procedure-related mortality and a low complication rate makes CIPII feasible for selected patients with diabetes.

[Spinal granuloma in a patient receiving a spinal infusion of morphine and clonidine]. / Granuloma intradural en un paciente con infusión espinal de morfina y clonidina.

Patients treated with long-term spinal infusion of high doses of morphine develop a granuloma at the location of the catheter tip. Diagnosis is based on a steady increase in intrathecal morphine dosage after a relatively prolonged period of stability, on the gradual development of neurologic signs and symptoms suggesting radicular or spinal cord compression, and on magnetic resonance images. We describe a man with central neuropathic pain after removal of a tumor. The presence of all 3 of the aforementioned diagnostic criteria led to suspicion of a spinal granuloma.