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1、IntestinalObstructionIntestinalobstructiondesignatesanimpairmentofmovementofintestinalcontentsinacephalocaudaldirection.Thecausescanbecategorizedasmechanicalobstructionandparalyticobstruction.Strangulationwithnecrosisofthebowelmayoccurandleadtoperforation,peritonitis
2、andsepsis.Itisaseriouscomplicationandmayincreasethemortalityrateofintestinalobstructiontoabout25%.MechanicalObstructioncanresultfromanumberofconditions，intrinsicandextrinsicthatencroachonthepatencyofthebowellumen.Majorincitingcausesincludeexternalhernia(i.e.,inguinal
3、,femoral,orumbilical)andpostoperativeadhesions.Lesscommoncausesarestrictures,tumors,foreignbodies,intussuceptionandvolvulus.Intussusceptioninvolvesthetelescopingofbowelintotheadjacentsegment.Itisthemostcommoncauseofintestinalobstructioninchildrenyoungerthan2yearsofag
4、e.Themostcommonformistheintussusceptionoftheterminalileumintotherightcolon,butotherareasofthebowelmaybeinvolved.Inmostcases,thecauseofthedisorderisunknown.Theconditioncanalsooccurinadultswhenanintra-luminalmassortumoractsasatractionforceandpullsthesegmentalongasittel
5、escopesintothedistalsegment.Volvulusreferstoacompletetwistingofthebowelonanaxisformedbyitsmesentery.Volvulusofthecolonaccountsfor5%to10%oflargebowelobstruction.Mechanicalbowelobstructionmaybeasingleobstruction,inwhichthereisnoalterationinbloodflow,orastrangulationobs
6、truction,inwhichthereisimpairmentofbloodflowandnecrosisofboweltissue.Paralysis,oradynamic,obstructionresultsfromneurogenicormuscularimpairmentofperistalsis.Paralyticileusisseenmostcommonlyafterabdominalsurgery.Italsoaccompaniesinflammatoryconditionsoftheabdomen,intes
7、tinalischemia,pelvicfracturesandbackinjuries.Itoccursearlyinthecourseofperitonitisandcanresultfromchemicalirritantscausedbybile,bacterialtoxins,electrolyteimbalancesasinhypokalemia,andvascularinsufficiency.Themajoreffectsofbothtypesofintestinalobstructionareabdominal
8、distensionandlossoffluidsandelectrolytes.Gasesandfluidsaccumulatewithinthearea;ifuntreated,thedistentionresultingfrombowelobstructi
