Yuav Ua Li Cas Qhov Ncauj Ntawm Veress Needle Dictates Puncture Safety Thiab Tiv Thaiv Cov Hniav

https://en.wikipedia.org/wiki/Veress_needle

Hauv kev phais laparoscopic, lubVeress koobua hauj lwm raws li "thawj lub rooj vag" rau tsim pneumoperitoneum, thiab nws txoj kab uas hla yog tsis muaj txhais tau tias arbitrary. Raws li cov qauv kev lag luam, sab nraud txoj kab uas hla (OD) ntawm Veress koob feem ntau yog li ntawm 2.5 hli mus rau 5 hli, thaum lub puab kab (ID) yog tswj ntawm 1.5 hli thiab 3 hli. Qhov no zoo li qhov yooj yim qhov ntev ntau encapsulates kaum xyoo ntawm kev tshawb fawb rau hauv engineering mechanics thiab biomechanics ntawm cov ntaub so ntswg sib cuam tshuam.

Txoj kab uas hla thiab qhov sib npaug ntawm Insertion Force

Los ntawm qhov kev xav ntawm engineering mechanics, rab koob txoj kab uas hla ncaj qha cuam tshuam rau lub zog axial xav tau rau kev ntxig. Ib rab koob zoo dua (piv txwv li, OD 2.5 hli) ntsib qhov tsis kam qis thaum nkag mus rau hauv lub fascia thiab peritoneum, theoretically txo qhov "ntxuav cov nyhuv" tshwm sim los ntawm kev tawg tam sim ntawd - qhov twg rab koob nrawm nrawm nrawm thaum tawm ntawm cov ntaub so ntswg, muaj feem cuam tshuam rau hauv plab hnyuv lossis cov hlab ntsha. Txawm li cas los xij, cov ncej nyias nyias tsis muaj zog txaus; Thaum ntsib cov phab ntsa tuab hauv plab (piv txwv li, hauv cov neeg mob rog), nws yog qhov yooj yim rau buckling, ua rau kev sib txawv ntawm qhov kev nkag mus thiab ua rau muaj kev pheej hmoo ntawm kev raug mob. Yog li ntawd, 2.5 hli OD feem ntau yog tshwj tseg rau cov neeg mob menyuam yaus lossis cov neeg laus nyias, thaum lub 4-5 hli OD yog tus qauv rau cov neeg laus lossis cov neeg mob rog kom txaus flexural rigidity.

Inner Diameter thiab Kev Pom Zoo ntawm Gas Flow Rate

Lub puab txoj kab uas hla dictates cov efficiency ntawm carbon dioxide insufflation. Raws liPoiseuille Txoj Cai, lub volumetric flow rate yog proportional rau plaub lub hwj chim ntawm lub vojvoog. Qhov no txhais tau hais tias nce tus ID los ntawm 1.5 hli mus rau 3 hli yields ib tug theoretical 16-fold nce nyob rau hauv flow rate. Txawm li cas los xij, tus ID loj dua yuav tsum muaj phab ntsa tuab dua lossis loj dua OD, yog li ua rau cov nqaij ntshiv. Cov kws kho tsheb yuav tsum pom qhov sib npaug ntawm qhov nrawm nrawm thiab qhov cuam tshuam tsawg kawg nkaus: cov koob Veress niaj hnub no feem ntau siv tus ID ntawm kwv yees li 2 hli, ua ke nrog cov cua kub siab insufflators, ua kom tiav qhov pib 2-3 litre inflation li ntawm 30 vib nas this thaum tswj qhov OD tsis tshaj 3.5 hli, ntsuas qhov ua tau zoo nrog kev nyab xeeb.

Synergistic Design: Tapered Tip thiab Diameter

Lub cannula ntawm Veress koob nta ib daim kab xev. Qhov no tsis yog ib qho kev xaiv zoo nkauj tab sis ib qho kev tsim qauv tsim los siv kev hloov pauv hloov mus rau "progressive dilation." Thaum lub taub hau nkag mus rau ntawm daim tawv nqaij, lub conical nto nce mus rau cov nqaij fibers thiab rog sib nrug, tsis yog incising lawv zoo li ib tug ncaj hniav. Qhov kev tsim no ua kom ntseeg tau tias qhov tseeb cov ntaub so ntswg tsim muaj tsawg dua li rab koob OD-piv txwv li, ib rab koob conical nrog 5 hli OD tuaj yeem ua rau cov ntaub so ntswg ntau tshaj qhov tsim kua muag ntawm tsuas yog 3 hli. Qhov no piav qhia yog vim li cas qhov tshwm sim ntawm qhov chaw nres nkoj tom qab- qhov chaw los ntshav tseem qis heev txawm tias siv cov koob loj heev -caliber koob.

Yav Tom Ntej Engineering Trends: Variable Diameter and Smart Feedback

Cov kev tshawb fawb tam sim no tab tom tshawb nrhiav "dilating" Veress koob: pib nrog qhov pib OD ntawm tsuas yog 2 hli, lub ncej mechanically expands mus rau 4 hli ib zaug hauv plab, kom ntseeg tau tias qis - tiv thaiv ntxig thaum muab cov pa roj txaus. Tsis tas li ntawd, qee qhov kev tsim cov koob siab dhau los ua ke nrog cov ntsuas siab los saib xyuas qhov tseeb - lub sijhawm hloov pauv ntawm lub ntsis. Yuav tsum kuaj pom qhov txawv txav siab (xws li muaj peev xwm tiv tauj nrog viscera), lub kaw lus tso tseg tam sim ntawd. Cov kev tsim kho tshiab no vam khom rau kev nkag siab tob txog txoj kab uas hla -txoj kev sib raug zoo.

Xaus

Nyob rau hauv cov ntsiab lus, txoj kab uas hla ntawm Veress koob tsis yog tsuas yog ib tug raug parameter; nws yog ib tug choj txuas engineering cov qauv rau kev phais kev nyab xeeb. Txhua millimeter hloov kho qhia tau hais tias muaj kev hwm zoo rau cov ntaub so ntswg nyob thiab kev suav zoo.