Biomaterial Database

Microprocessor-assisted solvent-transfer system for gallstone dissolution. In vitro and in vivo validation. 1990

S F Zakko, and A F Hofmann

Department of Medicine, University of Connecticut, Farmington.

To improve the efficacy, safety, and convenience of contact dissolution of gallbladder stones, a microprocessor-assisted solvent transfer system was developed. The system's two pumps simultaneously infuse and aspirate solvent into and from the gallbladder at a high flow rate through a multilumen catheter. The microprocessor controls the pumps using a closed feedback loop control algorithm to regulate intragallbladder pressure to prevent solvent escape into the duodenum. Turbulent solvent flow at the catheter end in the gallbladder is designed to induce rapid stone dissolution and to suspend insoluble residue, thus promoting its aspiration. The system's response and gallbladder emptying capacity was 160-fold faster than the natural gallbladder emptying rate. The rate at which gallstones were dissolved by methyl tert-butyl ether using the system was compared with that achieved with a syringe pump. For 6 of 11 pairs of stones that totally dissolved, the mean dissolution time with the system was 10 +/- 6 minutes compared with 112 +/- 81 minutes for the syringe pump. In the 5 of 11 stone pairs which dissolved incompletely, insoluble residue was completely eliminated by the system in 21 +/- 9 minutes but not by the syringe pump even at 360 minutes. When the system was used in gallstone patients, solvent recovery was 99% +/- 1%, and the concentration of a nonabsorbable marker did not change, confirming the lack of appreciable absorption of methyl tert-butyl ether. These studies suggest that the microprocessor-assisted solvent transfer system is a device capable of safe, complete, and fully automatic contact dissolution of cholesterol gallbladder stones using methyl tert-butyl ether or similar solvents.

UI	MeSH Term	Description	Entries
D008738	Methyl Ethers	A group of compounds that contain the general formula R-OCH3.	Ethers, Methyl
D008838	Microcomputers	Small computers using LSI (large-scale integration) microprocessor chips as the CPU (central processing unit) and semiconductor memories for compact, inexpensive storage of program instructions and data. They are smaller and less expensive than minicomputers and are usually built into a dedicated system where they are optimized for a particular application. "Microprocessor" may refer to just the CPU or the entire microcomputer.	Computers, Personal,Microprocessors,Computer, Personal,Microcomputer,Microprocessor,Personal Computer,Personal Computers
D011930	Reaction Time	The time from the onset of a stimulus until a response is observed.	Response Latency,Response Speed,Response Time,Latency, Response,Reaction Times,Response Latencies,Response Times,Speed, Response,Speeds, Response
D002404	Catheterization	Use or insertion of a tubular device into a duct, blood vessel, hollow organ, or body cavity for injecting or withdrawing fluids for diagnostic or therapeutic purposes. It differs from INTUBATION in that the tube here is used to restore or maintain patency in obstructions.	Cannulation,Cannulations,Catheterizations
D002769	Cholelithiasis	Presence or formation of GALLSTONES in the BILIARY TRACT, usually in the gallbladder (CHOLECYSTOLITHIASIS) or the common bile duct (CHOLEDOCHOLITHIASIS).	Gallstone Disease,Cholelithiases,Gallstone Diseases
D004322	Drainage	The removal of fluids or discharges from the body, such as from a wound, sore, or cavity.
D004864	Equipment and Supplies	Expendable and nonexpendable equipment, supplies, apparatus, and instruments that are used in diagnostic, surgical, therapeutic, scientific, and experimental procedures.	Apparatus and Instruments,Devices,Medical Devices,Device, Medical,Devices, Medical,Equipment,Inventories,Medical Device,Supplies,Device,Instruments and Apparatus,Inventory,Supplies and Equipment
D004867	Equipment Design	Methods and patterns of fabricating machines and related hardware.	Design, Equipment,Device Design,Medical Device Design,Design, Medical Device,Designs, Medical Device,Device Design, Medical,Device Designs, Medical,Medical Device Designs,Design, Device,Designs, Device,Designs, Equipment,Device Designs,Equipment Designs
D004987	Ethers	Organic compounds having two alkyl or aryl groups bonded to an oxygen atom, as in the formula R1–O–R2.
D005069	Evaluation Studies as Topic	Works about studies that determine the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies.	Critique,Evaluation Indexes,Evaluation Methodology,Evaluation Report,Evaluation Research,Methodology, Evaluation,Pre-Post Tests,Qualitative Evaluation,Quantitative Evaluation,Theoretical Effectiveness,Use-Effectiveness,Critiques,Effectiveness, Theoretical,Evaluation Methodologies,Evaluation Reports,Evaluation, Qualitative,Evaluation, Quantitative,Evaluations, Qualitative,Evaluations, Quantitative,Indexes, Evaluation,Methodologies, Evaluation,Pre Post Tests,Pre-Post Test,Qualitative Evaluations,Quantitative Evaluations,Report, Evaluation,Reports, Evaluation,Research, Evaluation,Test, Pre-Post,Tests, Pre-Post,Use Effectiveness