VMED 5315 Large Animal Surgery PDF
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This document describes surgical procedures involving the head of goats, including dehorning and disbudding. It details techniques, complications, and post-operative care. The document focuses on large animal surgery procedures.
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VMED 5315 Large Animal Surgery MODULE V SURGERY INVOLVING THE HEAD I. Caprine Dehorning ❖ T he cornualbranchoftheinfratrochlear...
VMED 5315 Large Animal Surgery MODULE V SURGERY INVOLVING THE HEAD I. Caprine Dehorning ❖ T he cornualbranchoftheinfratrochlear and lacrimal nervesinnervatethehornof Purpose the goats ❖ G oats with horns pose a threat ★ Cornual branch of the infratrochlear nerve: ❖ Goats withouthornsarelessdestructiveto dorsomedial to the rim of the orbit farmfacilitiesandarelesslikelytobecome entangled in fences ❖ Dehorning can be combined with ★ Cornual branch of the lacrimal nerve: descentingin males halfway between the lateral canthus of the eye and the Exemptions posterior edge of the horn along ❖ G oats that range or are kept on tethers the cornual ridge behind the should beallowedtokeeptheirhornsasa supraorbital process defense mechanism. ❖ Dehorned bucks may be less able to compete with horned herd mates for breeding purposes ❖ Dehorning in adulthood may have secondary complications that include delayed healingandpossibly death. ❖ Given the complications and costs associated with dehorning, selectbreeding for polled goats would seem to be advantageous. ❖ However,goatshave ❖ Local anesthesia is performed inkidsby: a dominant polled - Injecting 1 mL of a solution (1 mL gene, also have a of2%lidocainedilutedwith3mLof close link to an sterile water) into each of four infertility recessive sitesrequiredtoblockthetwohorn gene. buds I.A Disbudding Surgical Technique ❖ R emoval of horn buds in young goats A. Disbudding ❖ Should be performed within the first week ❖ H eat cautery is the most commonly used of life technique ❖ European breeds: The hair over the horn bud is Buck kids- between3 and 5 days clipped to improve visualization Doe kids- between5 and 7 days anddecreasetheamountofsmoke inhaled by the person performing ❖ Nubian breeds: until two weeks of age the disbudding Restraint And Anesthesia O nce the dehorning iron has ❖ S everal methods of restraint and become cherry red, it should be anesthesia are available for disbudding kids applied to the horn bud for 3 to 4 ❖ Physical restraint can be usedalone seconds ❖ Others use a combination of: physical restraint T heheadshouldbeallowedtocool local anesthesia before reapplying the iron for sedation another 3 to 4 seconds general anesthesia T wo applications of the iron should be adequate to completely Disbudding box/ Kid holding box destroy the horn corium, andthis is assured if there is a ring of copper-coloredskinthatencircles the horn bud HNB ❖ T he circle ofskininsidetheringshouldbe ❖ O ncethetipofthehornhasbeenremoved, burned as well heat cautery is appliedtotheedgesofthe ❖ Buck kids require a larger ring of burnt wound to burn the skin around the horn skin than doe kids do base as described for disbudding. ❖ Bucks can also be descented at this time by burning an additional crescent of skin Adult Goats caudomedialto each horn bud ❖ T he risks and benefits of dehorning adult goats must be fully considered before attempting this procedure. ❖ In addition to the risks of tetanus, sinusitis, myiasis, abortion, and death associated with dehorning an adult dairy goat,thewoundleftafterthisprocedurewill leave alarge defect in the frontal sinus. Complications - This defect may take months to 1. Inadequateburningleadstoscarformation close, if it closes at all. and excessive burning that leads to heat ❖ After the procedure, the goat will need to meningitis. beisolatedfromothergoatstoavoidinjury untilhealingiscomplete,andthegoatmay 2. T he frontal bone’s thinness and the lose its social status within the herd. absence of a frontal sinus inkidsmake themproneto heat meningitis. Anesthesia: 1. Adult goats should be withheld from feed 3. S igns of heat meningitis include for12 to 24 hoursbefore surgery. unresponsiveness and an inability to 2. Two local blocks per horn should be nurse. performed by using1 mL of 2% lidocaine. 3. A ring block can be performed aroundthe 4. T reatment with antibiotics, horn as well, being careful not to exceed anti-inflammatory agents, supplemental thetoxic dose of 13 mg/kgof lidocaine. heat, and tube feeding may allow some affected kids to recover from this condition. B. Dehorning ost Operative Care P Adult Goats 1. Pressurizedaerosolofantibioticpowder ❖ T heskinisincised1.5cmfromthebaseof should be applied to the wound the horn, leaving at least a 1-cm strip of skin between the two horns. 2. K ids should be kept warm, in sternal recumbency,untiltheanesthesiahasworn ❖ A Gigli wire saw is seated into the off completely caudomedial aspect of the skin incision, andthehornissawedoffinacraniolateral 3. T etanus prophylaxis should be given at direction to avoid cutting too deeply into thistime—includingboth250IUoftetanus the skull and entering the cranial cavity. antitoxin and two doses of tetanus toxoid using separate syringes in two ❖ T he horn must be supported during the different locations cutting process to prevent thefrontalbone from fracturing. ❖ O nce the horn has been removed, the superficial temporal artery (located laterally) should be pulled, cauterized, or Older Kids ligated. ❖ T he horn of kids become large enough within a couple of weeks preventing a ❖ T hescentglandsofmalegoatslocatedat dehorning iron from reaching the skin the caudomedial base of each horn can around the base of the horn. also be removed at this time. ❖ To dehorn these older kids, the tip of the protrudinghornmustberemovedbefore ❖ W hendonecorrectly,dehorningwillleavea the dehorning iron can be applied. large opening in the frontal sinus. The hoof nippers, shears, or a small procedure must be performed as Barnes dehorner aseptically as possible with any clots or bonedustremovedfromthesinustoavoid developing sinusitis. HNB III. Trephination Cattle - Frontal Sinus ❖ Indicated in chronic empyema, which in adultcattleiscausedusuallybyinfectionof the sinus following dehorning or horn fracture omplications C ❖ T he sinusitis is often confined onlytothe ❖ Dehorninggoatsofanyageisnotabenign caudal part of the sinus, but in procedure,andthechanceofpostoperative long-standing cases the entire sinus may complications becomes more severe the be involved longer the procedure is delayed. the sinus is obtained bytrephining 2 cm from the midline on a line ❖ In addition to the complications of: passing through the centre of the orbits . a etanus T b. Thermal meningitis ❖ If the original opening to the sinus at the c. Sinusitis siteofthedehorningwoundisnarrowedor d. Myiasis closed by granulation tissue, it isenlarged e. Loss of social status or re-opened under cornual nerveblockto f. Scar formation facilitate adequate flushing of the sinus the stress of dehorning may lead to other Surgical Technique c omplications such as: A. Trephination - Cattle ❖ T rephinationiscarriedoutonthestanding . A g bortion animal under local analgesia. h. Listeriosis. ❖ A napproximately5cmlongverticalincision II. Descenting Bucks is made through skin, subcutis and ❖ S ituated in the periosteum caudomedial aspect of the ❖ T he periosteum is horns, and can be dissected from the identified as a bone and drawn shiny, hairless, aside, together with crescent-shaped the skin, with patch of skin retractors with pores. ❖ T hepointofthetrephineisinsertedintothe ❖ A lthough removing the scent glands bone and trephination is performed by decreases a buck’s odor, only castration rotating the trephine. entirely removes the buck’s smell. ❖ Trephination is continued through the full thicknessof the bone Surgical Technique ❖ T he disc is removed Descenting with a bone screw ❖ T hebuckshouldbesedatedandtheskinto insertedintothehole be removed should be infiltrated with made previously by lidocaine. the point of the ❖ A crescent-shaped piece of skin can be trephine removed and the area closed surgically. ❖ T o remove exudateandnecrotictissuethe ❖ A lternatively, if the scent glands extend sinus is flushed thoroughly with an further from the horn base, a triangular antiseptic solution. flap of skin with the apex located on the ❖ To prevent premature closure of the midline 3 to 4 cm in front of the rostral openings they are packed with gauze aspect of the horns can be reflected bandage plugs. caudallyto fully expose the scent glands. ❖ P ostoperative flushing is repeateddaily, ❖ T hescentglandscanthenberemovedand untilthesinushashealed,asevidencedby the skin flap sutured back into place absence of purulent discharge HNB B. Horse - Maxillary Sinus ❖ Intra-operative radiography is ❖ Indicated in cases of empyema, cysts or recommended to ensurethatnofragments neoplasms, and for repulsion of upper remain molar teeth. ❖ Thealveolusandtrephinationholearethen packed with povidone iodine soaked gauze ❖ T he rostral maxillary sinus is trephined ❖ Postoperatively flushes are repeated about2-3cmdorsaltotherostralendofthe facial crest ❖ T he plug placed in the alveolus after flushing must be somewhat smaller than ❖ T he caudal maxillary sinus is trephined the previous one, in order to enable 2-5 cm rostral to the medial canthus and granulation tissue to gradually fill the 2-3 cm dorsal to the facial crest. alveolus; the plugs in thetrephinationhole are ofconstant size. ❖ Care must be taken to avoid damage ❖ W hen the alveolus is closed off by to thenasolacrimal duct granulation tissue and exudation in the sinus has ceased, the trephination hole is allowed to be closed C. Trephination with Tooth Repulsion - orse H ❖ T heoperationmaybecarriedouteitheron the standing animal under local infiltration analgesia, or on the recumbent animal IV. Suturing of Eyelid Lacerations under general anesthesia. ❖ E yelid lacerations in horsesareoftenfull- ❖ In case of tooth repulsion general thickness, i.e. involving skin, orbicularis anesthesia is required. oculi muscle and conjunctiva. Usually the ❖ At theselectedsiteanapproximately4cm upper eyelidis torn. long incision is made parallel to the facial ❖ Incasesofrecentlacerationre-apposition crest through the skin and subcutaneous and careful suturingmust be attempted. tissue ❖ Theskinandperiosteumaredrawnaside with wound retractors ❖ Thediscis removed with a bone screw. ❖ In empyema caused by alveolitis, the sinus is flushed and the affected tooth is carefully located. ❖ A punch is then introduced into the sinus andplacedupontherootsofthetoothtobe repelled Oxytetracycline + ❖ After removal the tooth is examined to olymyxin B sulfate P determine if it is complete. Any tooth or bony fragments must be removed Surgery A. S tanding animal under local analgesia (infiltrationorfrontal nerve block), or B. Recumbentanimalunderlocalanalgesiaor general anesthesia. ❖ Eye is flushed with physiologic saline. ❖ Sharp superficial excision of the wound edges is then carried out. ❖ Suturing begins atthesiteofthepalpebral margin(simple interrupted suture) ❖ The conjunctiva is not sutured toprevent damage to the cornea. HNB VI. Eye Enucleation ❖ R emovaloftheglobetogetherwiththe(1) bulbar and (2) palpebralconjunctiva,the (3) nictitating membrane and the (4) lacrimal gland. ❖ Indicated in cases of eyelid or eyeball neoplasia, gross injuries of the eyeball (corneal rupture)andpanophthalmitis. ❖ S urgery under General anesthesia with ophthalmic nerve regional analgesia of thelower eyelid and medial canthus ❖ T he orbicularis oculi muscle and skin are sutured together (interrupted vertical mattress sutures or with deep simple interrupted sutures alternating with superficial simple interrupted sutures) ❖ D eep bites- skin together with the orbicularis oculi muscle. ❖ Superficial bites-only the skin. ❖ E itherabsorbableornon-absorbablesuture material may be used. ❖ Sutures are left in place for at least one week. ❖ U pper and lower eyelids are sutured ❖ Ophthalmic antibiotic ointment, BID for 7 (continuous suture). days.(Terramycin, neomycin or polymyxin) ❖ A n elliptical incision (0.5-1 cm)fromand parallel to the margin of the eyelids and V. Excision of Third Eyelid palpebral muscle. ❖ Indicated in case of tumorous growth (squamous cell carcinoma). ❖ B y blunt dissection in the direction of the orbital ridge theorbit is entered. ❖ T hird eyelid and conjunctival sac are infiltratedwithlocal analgesic ❖ T he retrobulbar tissues and extra-ocular muscles are dissected bluntly and ❖ T hird eyelid is held with a forceps and transected as close to the globe as drawn away from the conjunctival sac. possible. ❖ C omplete excision deep to the cartilage ❖ R etractor bulbi muscle,ophthalmicvessels using curved blunt-pointed scissors. and optic nerve areclampedwithcrushing forceps and transected between forceps ❖ H emorrhage is controlled by pressurewith and globe. a gauze swab soaked in 0.01% epinephrine solution. ❖ T he eyeball is then withdrawn from the orbit. The lacrimal glandis then removed. ❖ T he forceps is removed; hemorrhage may be controlled either by vessel ligation or packing the orbit with sterile gauze bandages. ❖ E yelids are sutured together with interruptedsutures,leavingasmallopening mediallyfor the gauze drain. ❖ T he gauze packingisremovedafter2to3 days. HNB VIII. Guttural Pouch Drainage ❖ Indicated in chronic empyema, chondroidsandtympany(in foals). ❖ It is opened through Viborg's triangle, (bounded by (1) linguofacial vein, the tendon of the sternocephalic muscle, and the(2)vertical ramus of the mandible) ❖ A 3-5 cm incision is made dorsal and parallel to the vein through the skin and subcutaneous fascia. VII. Nasolacrimal Orifice Atresia ❖ T he connectivetissueattheventralborder ❖ A tresiaofthenasalopeningofthetearduct of the parotid is bluntlydissected,untilthe may be the cause of chronic lacrimation guttural pouch submucosa has been in foals. reached. A fold is carefully elevated and ❖ A catheter is introduced into the lacrimal opened. duct of lower eyelid. It will be advanced ❖ G uttural pouch is sutured to the edges of carefully down thetearduct,untilthetipis the skin wound. palpable beneath the nasal mucous ❖ Abnormal contents are removed by membrane. flushing. ❖ T he nasal mucosa and the mucosa of the blindendoftheductareincisedoverthetip of the catheter, after which the catheter is pushed through the opening created. ❖ T he mucous membrane of the duct is sutured to the nasal mucous membrane. (Simple interrupted sutures of fine absorbable material). ❖ A rubber tube isinsertedintothedrainage ❖ T he catheter is then sutured to theskinin opening and fixed totheskinwithsutures. the nasal and eyelid regions and left in Post-operative flushing is carried out. place for at leasttwo weeks. ❖ In unilateral tympanythetympanicpouch ❖ A ntibiotic ophthalmic ointments are is opened through Viborg's triangle, and a administered into the conjunctival sac and fenestrationismadeintheseptumbetween corticosteroids may be added for several therightandleftgutturalpouch,usinglong days to reduce edema andfibrosisaround tissue forceps and scissors. the created orifice. ❖ Inbilateraltympanyonepouchisopened, fenestration performed, and the mucous membrane flap (valve) at the outlet of the Eustachian tube of the opened pouch dissected. HNB IX. Laryngotomy (CRICOARYTENOIDOPEXY AND VENTRICULECTOMY) ❖ Indicated for inspiratory dyspnea due to laryngeal hemiplegia(roaring)toenlarge the reduced laryngeal lumen. ❖ T he combination of cricoarytenoidopexy with unilateral or bilateral ventriculectomy has given the best results. ❖ A double ligature of heavy-sized chromic catgut is preferred for the Ventriculectomy cricoarytenoidopexy. ❖ T he patient is then positioned in dorsal recumbency. The laryngeal cavity is ❖ T he dorsolateral aspect of the larynx is opened; thecrycoid cartilage is not incised. dissected. ❖ T hemucousmembraneoftheleftlaryngeal ❖ T he muscular process of the arytenoid saccule is removed andtheindexfingeris cartilage is penetrated from medial to brought submucosally to free and then lateral. evert the mucous membrane. ❖ T heevertedmucousmembraneisresected without damaging the adjacent cartilage. The skin is closed with a non-absorbable interrupted sutures. Cricoarytenoidopexy ❖ T he medial part of the ligature is brought X. Tracheostomy under the crycoarytenoid muscle. ❖ Indicated to relieve dyspnea caused by operation on sinuses, acute nasal, ❖ T he needle is thenpassed,frommedialto laryngeal or proximal tracheal obstructions. lateral, through the caudal border of the cricoid cartilage. ❖ T he head and neck of the animal are extended, an approximately 7 cm ventral ❖ T he needle passes through the cartilage, midlineskinincisionismadeinthecranial but not through mucous membrane and third of the neck at the level of the lumen. 4th-6th tracheal ring. ❖ T he medial part of the thread is threaded ❖ A fter incising the thin cutaneousmusclein into the needle and pulled through the the midline, the longitudinal junctionofthe cricoid cartilage. sternohyoid muscles is divided and the tracheaexposed.Themusclesandskinare ❖ T he two ends of the ligature are tied with spread with a wound retractor. sufficient tension to fully retract the arytenoid cartilage;thiscanbecheckedby ❖ If temporary tracheostomy is indicated, a laryngoscopy. tracheal annular ligament is piercedwitha scalpel and a tracheal tube (ovoid in ❖ T hesubcutaneousanddeepfascialtissues cross-section)is inserted. are closed (simple continuous suture) and the skin with (interrupted sutures) using ❖ If tracheostomy tube is required for long synthetic absorbable material. period,partialresectionofatrachealringor discis performed. HNB ❖ T opreventthetrachealringfromcollapsing, resection of a semi- disc of the tracheal rings proximal and distal to an incision through the annular ligament is recommended. ❖ A fter tracheostomy a self-retaining tube is inserted,theskinedgesaresuturedaround the tube in asimple interrupted pattern. ❖ T he tube is checked and cleaned daily. After the tube is withdrawn, the tracheostomy wound heals by second intention. HNB VMED 5315 Large Animal Surgery MODULE VI PART 1 APPROACHES TO THE BOVINE ABDOMEN ANATOMY ❖ It inserts on the tuber coxae, prepubic ❖ T he conformation of the bovine abdomen tendon, and linea alba by means of varies with age, weight, and physiologic aponeurotic tissue. condition. ❖ T he aponeurosis of the EAO blends with ❖ Normally it isbilaterally symmetric. the aponeurosis of the internal abdominal ❖ T he extent of the abdominal cavity is not obliquemuscletoformtheexternalsheath readily apparentbecausealargeportionis of the rectus abdominis muscle. within the ribcage.Theabdominalcavityis ❖ T he internal abdominal oblique muscle bounded: (IAO) isimmediately under the EAO. Cranially by thediaphragm Caudally by thepelvic inlet ❖ T he IAO originates from the tuber coxae, Dorsally by the lumbar vertebrae lumbar transverse processes, and the andepaxial musculature thoracolumbar fascia. Laterally and ventrally by the abdominal musculature. ❖ Itsfibersaredirectedcranioventrally.The fibers of the IAO insert on the costal ❖ T heabdominalwallmusculatureismadeof cartilages or via anaponeurosisthatfuses broad expansive sheets that attach by withthatoftheexternalabdominaloblique, means of aponeuroses-forming which forms the external sheath of the connective tissue structures such as the rectus abdominis, which inserts on the linea albaandprepubic tendon. linea alba. ❖ T he abdominal musculature also permits ❖ T he TA arises from the transverse generation of an abdominal press processes of thelumbarvertebraeandthe necessary for defecation, micturition, and medial aspect of the last ribs. parturition. ❖ It forms anaponeurosisatthelateraledge ❖ T heabdominalwalliselasticinnature,thus of the rectus abdominis muscle, becomes allowing it to adjust to varying volumes. the inner sheath of the rectus abdominis, and ultimately inserts on the ❖ T he skin is thickest over the flank of the linea alba. cow andbecomesthinnerovertheventral portionof the abdomen. ❖ T he transversus abdominis is covered on the inside by the transverse fascia and ❖ T he most prominent feature of the bovine peritoneum. flankis theparalumbar fossa. ❖ T he rectus abdominis muscle (R A) is ❖ Theparalumbar fossais outlined by the: confined to the ventral aspect of the transverseprocessesofthelumbar abdomen and travels oneithersideofthe vertebrae linea alba. internal abdominal oblique muscle thirteenth rib ❖ Itoriginatesfromthecostalcartilagesofthe ribsandsternumandinsertsonthecranial ❖ A bdominal muscles and theiraponeuroses pubic ligament. form the mainfibromuscularsupportofthe ventral and lateral walls of the abdomen. ❖ T he rectus abdominis muscle lies within ❖ The fibers of this muscle course in a anaponeuroticsheaththatisformedbythe caudoventral direction. aponeurosesof theEAO, IAO, and TA. ❖ H owever, in the area o f the paralumbar ❖ T he linea alba extends from the xiphoid fossa the fibers are seen in a more process and inserts on the prepubic horizontal direction. tendon. ❖ T heEAOoriginatesonthelateralaspectof ❖ T he fibers of each sheet cross between the thoraxfrom thefourth or fifth rib. each other, which adds to its mechanical strength. HNB ❖ T hethicknessandwidthvarydependingon I. Left Paralumbar Fossa Celiotomy the location relative to the umbilicus. ❖ T he left flank should be clipped and asepticallyprepared,andlocalorregional ❖ T he linea is much thicker and wider at anesthesia should be used to desensitize the level of the umbilicus. the surgical area. Sterile draping should follow. ❖ It becomes thinner and narrower as it coursescranially. ❖ Thelocationfortheskinincisionistypically (1)centered over the paralumbar fossa. ❖ Theskin incisionis begun: 6 to 8cmventraltothetransverse processes of the lumbar vertebrae and 4 to 6 cmcaudal to the last rib. The incision is made in a ❖ S omeportionsoftheintestinaltractcanbe dorsoventral direction for a exteriorized;someonlypalpated,andother length of20 to 25 cm. portions are inaccessible. ❖ T he (2) external abdominal oblique ❖ T he surgeon must also consider the muscleisincisedinthesamedirectionand disease process when choosing an for the same distance as the skin incision. approach so that the organ(s) of interest can be accessed. ❖ T he fibers of the (3) internal abdominal oblique are nowvisible.Thismusclelayer ❖ O ther factors such as value of theanimal, is incised in the same manner as the available facilities, temperament of the external abdominal oblique. patient,andexperienceofthesurgicalteam all influence the chosen approach. ❖ T he (4) transversusabdominismuscleis encountered next. To prevent damage to underlying viscera upon entering the abdomen, it is helpful to “tent” the transversus abdominus by using thumb forceps and to incise the muscle and peritoneum the length of the incision by usingMayo scissors. ❖ T he reproductive tract, bladder, ureters, lymph nodes, and inguinal ringsshouldbe palpated. ❖ T heleftkidneyislargeandcoveredbyfat. It is easily palpable in the left caudal ❖ S chematicrepresentationoftheportionsof abdomen almost on midline, adjacent to the intestinal tractthatcanbeexteriorized, the descending colon. someonlypalpated,andotherportionsthat are inaccessible. ❖ O n the left side of the cranial abdomen the rumen, the spleen, reticulum, and ❖ U se of sedation or tranquilizers when diaphragm should be palpated. performing standing surgery is not advisable because the cow mightliedown ❖ T hepresenceofadhesionsorabscessesin during the procedure. the area of the reticulum and diaphragm should be ascertained. ❖ H owever, in some instances general anesthesia or recumbency and sedation ❖ T he surgeon can palpate portions of the are appropriate. right side of the abdominal cavity by goingbehind the rumen and forward. ❖ U se of perioperative antimicrobials and/or anti-inflammatories is at the ❖ T he internal abdominal oblique and discretion of the surgeon. external abdominal oblique muscles are closed separately with an absorbable HNB suture(#2insize)inasimplecontinuous ❖ T he descending duodenum can be seen attern. p justdeeptotheabdominalincision,running horizontally across the abdomen. ❖ B etween each layer of the closure, lavaging the muscles with sterile salineis ❖ T he right kidney is dorsal to the cranial advisable. portion of the descending duodenum underneath the last two ribs. ❖ T he skin is closed with a nonabsorbable suture (#1 in size), a Ford interlocking pattern, and three simple interrupted suturesattheventralmostaspectofthe incision. II. Right Paralumbar Fossa Celiotomy ❖ T he restraint, preparation, and approach III. Right Paramedian Celiotomy are the same as described in the left ❖ The incision is located: paralumbar approach. 4 to 6 cm lateraltoventralmidline and ❖ If a pyloropexy is anticipated, the initial 6 to 8 cmcaudal to the xiphoid. incision is made closer to the last rib in a moreventrallocationasdescribedforthe ❖ T he length of the incisionisapproximately left paralumbar fossa celiotomy. 15to20cm.Thecowshouldbepositioned and restrained indorsal recumbency. ❖ Inthecranialabdomen,thereticulumand diaphragm should be palpated for the ❖ T heareafromthexiphoidtocaudaltothe presence of adhesions or abscesses. umbilicus is clipped and aseptically prepared, and localanesthesiaisusedto ❖ T he omasum is identified caudal and desensitize the surgical field. medialtothereticulum.Itshouldbefilled withfirm ingesta. ❖ T he peritoneum and internal sheath ofthe rectus abdominis muscle are closed ❖ T he liver should be checked for rounded together. edges or irregularities. ❖ T herectusabdominismuscleisclosedwith ❖ It is normal or the edgesoftherightlobe an absorbable suture material (#2 in size) of the liver to be moreroundedthanthe in a simple continuous or interrupted left lobe. pattern. ❖ T hegallbladderisoftenenlargedincattle ❖ T he external sheath of the rectus that are anorectic. abdominis closed using an absorbable suture material (#2 in size) in a simple ❖ T he position of the abomasum should be continuousorinterrupted pattern. along the right body wall. The fundus or body of the abomasum normally contain ❖ C losureoftheskinisperformedbyusinga fluid consistency ingesta. nonabsorbable suture material (#1 in size) in aFord interlocking pattern. ❖ Ingesta in the pyloric portion is typically more dry and doughy.Thecranialpartof ❖ O ften the (1) caudal portion of the the duodenum in a fat cow maybe totally pectoral muscle is encountered at the obscured by fat. rostral aspectof this approach. HNB ❖ T his muscle is (2) divided to expose the IV. Ventrolateral Celiotomy external sheath oftherectusabdominis ❖ P ostpartum uterine lacerations can be muscles. accessed and sutured with this approach. ❖ T he (3) external sheath is incised sharply ❖ The incision is made: for the length of the incision. laterally to the subcutaneous abdominal vein (milk vein) and ❖ T he rectus abdominis muscle is (4) extends caudally exposed and incisedalongitsfiberswitha curving dorsally staying lateral to combination of sharp and blunt dissection. the attachment of the udder. ❖ T humb forceps are used to (5) tent the ❖ T he cow is restrained in lateral internal sheath of the rectus abdominis recumbency with the upper hind limb muscle and Mayo scissors are used to abducted andsecuredsotheinguinalarea incisethis layer. and base of the udder are accessible. ❖ O nce the incision has entered the ❖ T he area from the xiphoid cartilage to the abdominal cavity, (6) the surgeon can use inguinal region should be clipped and his or her fingers to protect underlying aseptically prepared. viscera whileextending the incision. ❖ T he (1) skin incision is made and the ❖ T heabomasumisusuallypositionedunder subcutaneous tissues are (2) divided to the incision unless it is displaced or the expose the externalsheathoftherectus rumen is gas distended. abdominis muscle. ❖ T he liver is palpable on the right side of ❖ T his layer is sharply incised, thereby the abdomen, thespleenon theleft. exposing the rectus abdominis muscle, which is (3) opened along its length by ❖ T he diaphragmisswepttocheckthatitis splittingmusclefiberswithacombinationof intact. sharp and blunt dissection. ❖ T he omasum is present lateral to the ❖ E xtreme caution should be used when abomasumand typically hasfirm ingesta. entering the abdominal cavity. ❖ T he abomasum is exteriorizedwithgauze ❖ T he gravid uterus is usuallybeneaththe spongesandthegreatercurvaturefollowed peritoneum. The internal sheath of the from the pylorus to the reticulum. rectus abdominis muscle is (4) elevated ❖ byusingthumbforcepsandthen(5) incised by usingMayo scissors. ❖ T he rectus abdominis muscle is closed with an absorbable suture material (#2 in size) in a continuous or interrupted pattern. ❖ T he external sheath of the rectus abdominis muscle is closed by using an absorbable suture material (#2 or #3 in size) in an interrupted or simple continuous pattern. ❖ F inally, the skin is closed with a nonabsorbable suture material (#1 in size) in aFord interlocking pattern. ❖ L avage of the soft tissue between closure layers is advisable. Seroma and peri incisional edema are very common with thisapproach. HNB V. Ventral Midline Celiotomy ❖ T he (1) skinincisionismadeparalleland5 ❖ T he cow is restrained in dorsal to10cm(adult)caudaltothelastrib.The recumbency, and the ventral abdomen lengthoftheincisionwillvarydependingon from the umbilicus to the udder and the surgical exposure needed. extendingtothefoldsoftheflankisclipped, aseptically prepared, and draped for ❖ A ftertheskinandsubcutaneoustissuesare surgery. incised (2)theaponeurosisoftheexternal abdominalobliqueisexposedandincised ❖ L ocal anesthesia is used to desensitize in the direction of the skin incision. the area. ❖ T he muscular portion of the internal ❖ Theskin incisionis started at the: abdominal oblique may be encountered umbilicus and extended caudally. dorsally and the aponeurotic portion continued through the ventrally. subcutaneous tissue to the level of the linea alba VII. Ventrolateral Celiotomy ❖ C losure of the incision is accomplishedby ❖ A (1) smallincisionmadethroughthelinea suturing the transversus abdominis and alba and peritoneum, while carefully peritoneum as the first layer with an avoiding underlying viscera, provides absorbable suture material. access to the abdomen. ❖ T he suture size will depend on thesizeof ❖ T he (2) incision through the linea alba is the animal. continued caudally. The surgeon can use ❖ The subsequentmuscle/aponeuroticlayers an instrument such as a thumb forceps to should be closed separately with an protectunderlyingvisceraastheincisionis absorbable suture material of appropriate extended. A sterile impervious sleeve size. should be used for exploration. ❖ F ord interlocking pattern. The skin is ❖ W hen using aventralmidlineceliotomyfor closed using a nonabsorbable suture cesarean section, some operators material in a Ford interlocking pattern. advocatetiltingthecow45to60degrees to facilitate delivery of the calf. ❖ T he closure of the aponeurosis of the externalabdominalobliquemuscleisthe ❖ T hisapproachmaybeespeciallyusefulfor strongest layer of this closure. fractious beef cattle. VIII. Left Oblique Celiotomy ❖ C losure of the incision should be in three ❖ A left oblique celiotomy h as been layers. The (1) lineaalbaisclosedwith#2 recommended for cows r equiring or #3 absorbable suture material in a cesarean section. simple continuous pattern or an interrupted pattern. ❖ The skin incision starts: 10 cm ventral to the transverse ❖ T he(2)subcutaneouslayerisclosedusing processes of the lumbar vertebrae #0 absorbable suture material in a and continuous pattern. anglesforwardtofinishatthelevel of the costochondral junction. ❖ T he (3) skin is closed u sing #1 nonabsorbable suture in a Ford ❖ T he abdominal oblique muscles are (1) interlocking pattern. sharplyincisedin the same direction. VI. Right Paracostal Approach ❖ T he transversus and peritoneum are (2) ❖ T his approach provides access to the tentedasfortheotherapproachesandare abdomen through the low flank. It can be incisedwithscissors. used to gain accesstotheabomasumin adult cattle and calves. ❖ It has been suggested thatthisapproach extends further cranial andventralthan ❖ T he animal is placed in left lateral the classical flank approaches, thus recumbency under general anesthesia. permitting superior manipulation and Theareaisclipped,prepped,anddrapedin exteriorization of the uterus. routine fashion. HNB VMED 5315 Large Animal Surgery MODULE VI PART 2 URGERY OF THE S GASTROINTESTINAL SYSTEM I. Umbilical Herniorrhaphy According to Condition of the contents Umbilicus 1. Uncomplicated umbilical hernias rachus-------------> vestigial part of the bladderapex U 2. Umbilical hernias with subcutaneous Umbilical Vein—-----------> round ligament of theliver infection/ abscesses Umbilical Artery—--> lateral ligaments of the bladder 3. Umbilical hernias with umbilical remnant infections 4. Umbilical abscesses/chronic omphalitis 5. Urachal cysts/ruptures Diagnosis istory H Signalment Complications Physical Examination Infection(Commonly isolated) Dx:Physical Examination(L ateral Recumbency) ❖ T rueperella pyogenes ❖ size ❖ Escherichia coli ❖ shape ❖ color ❖ presence of drainage ❖ consistency Herniation ❖ temperature Predisposition ❖ presence of pain . 1 enetics (Holstein-Friesian) G ❖ reducibility of the contents 2. Septic Omphalitis 3. Wound Dehiscence Dx:Ultrasonography 4. Increase abdominal pressure (defecation) ❖ Anechoic or Hypoechoic areas 5. Violent impact and Trauma Anatomy of Hernia General Considerations Hernial opening or ring ❖ H ernias associated with hereditary defects - Rupture, Prenatal opening, Normal should not be repaired Passage ❖ Unethical Practices vs Acceptable Practices Hernial Sac - cceptable mag repair to correct normal A - Layers: Skin, Muscle, Fibrous tissue, function but not acceptable (e.g) para tumaas yung value nung animal Peritoneum ❖ Inguinal hernias-emergencies ❖ ventral and umbilical hernias-elective Hernial Contents ❖ Small umbilical hernias in young animals Intestine occasionally resolve Omentum ❖ spontaneously or after conservative therapy Stomach Urinary Bladder Restraint and Anesthesia A. Uncomplicated Umbilical Hernia arieties of Hernia V Dorsalrecumbency,Sedationand According to site Local anesthetics Omphalocele-Umbilical cord
