title: Detection of spine structures with Bioimpedance Probe (BIP) Needle in clinical lumbar punctures.
abstract: Lumbar puncture is a relatively safe procedure, but some serious, even fatal, complications can occur. Needle guidance can increase puncture accuracy, decrease the number of attempts, and make the procedure easier. We tested the feasibility of a bioimpedance-based tissue-sensing technology for needle guidance in clinical use. The Bioimpedance Probe (BIP) Needle has a removable BIP stylet enabling measurement of bioimpedance spectra during the procedure. The BIP Needle is connected to a measurement device that uses tissue-classification software, and the device provides audiovisual feedback when it detects cerebrospinal fluid (CSF). We performed spinal anesthesia with the BIP Needle in 45 patients. The device performance and needle tip location were verified by an experienced anesthesiologist confirming CSF leakage. The device detected CSF in all cases (sensitivity of 100 %). Six cases with false detections lowered the specificity to 81 %, but in practice, most of these were easy to differentiate from true detections because their duration was short and they occurred during backward movement of the needle. The epidural spectrum differentiated as fatty tissue from surrounding tissues, but the ligamentum flavum was not clearly detectable in the data. The BIP Needle is a reliable tool for detecting CSF in lumbar puncture. It can make the puncture procedure smoother, as repeated CSF flow tests are avoided. The correct needle tip location is immediately detected, thus unnecessary needle movements close to spinal nerves are prevented. Physicians could benefit from the information provided by the BIP Needle, especially in patients with obesity or anatomic alterations.
authors: Department of Electronics and Communications Engineering, Tampere University of Technology, Korkeakoulunkatu 3, 33720, Tampere, Finland. sanna.halonen@injeq.com.|R&D Department, Injeq Ltd, Hermiankatu 22, 33720, Tampere, Finland. sanna.halonen@injeq.com.
authors: Sanna
authors: S
authors: Halonen
authors: Tampereen Lääkärikeskus Ltd, Hatanpään Valtatie 1, 33101, Tampere, Finland.
authors: Kari
authors: K
authors: Annala
authors: R&D Department, Injeq Ltd, Hermiankatu 22, 33720, Tampere, Finland.
authors: Juho
authors: J
authors: Kari
authors: Department of Anesthesia, Tampere University Hospital, Teiskontie 35, 33521, Tampere, Finland.
authors: Samuli
authors: S
authors: Jokinen
authors: Pirkanmaan Sairaanhoitopiiri, Valkeakoski Hospital, Salonkatu 24, 37600, Valkeakoski, Finland.
authors: Aki
authors: A
authors: Lumme
authors: R&D Department, Injeq Ltd, Hermiankatu 22, 33720, Tampere, Finland.
authors: Kai
authors: K
authors: Kronström
authors: Department of Anesthesia, Tampere University Hospital, Teiskontie 35, 33521, Tampere, Finland.|Medical School, University of Tampere, 33014, Tampere, Finland.
authors: Arvi
authors: A
authors: Yli-Hankala
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000775:Anesthesia, Spinal / Q000379:methods*; D002555:Cerebrospinal Fluid; D017097:Electric Impedance; D004824:Epidural Space; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D009339:Needles; D011677:Punctures; D013116:Spinal Cord; D013129:Spinal Puncture / Q000379:methods*; D013131:Spine / Q000601:surgery*; D055815:Young Adult
keywords: Bioimpedance; Cerebrospinal fluid; Epidural; Monitoring; Needle guidance; Spinal anesthesia