4Y Dystocia Workshop 2021 PDF

Calving and Dystocia in cattle Rob Smith How you will learn • • • • This lecture as reference Calving Simulator EMS Caesarean video from Utrecht in Reproduction week of rotations • PCEMS Lambing • • • • • • • • • • • Outline Stages of labour Ideal calving facilities When to intervene What to...

Calving and Dystocia in cattle Rob Smith How you will learn • • • • This lecture as reference Calving Simulator EMS Caesarean video from Utrecht in Reproduction week of rotations • PCEMS Lambing • • • • • • • • • • • Outline Stages of labour Ideal calving facilities When to intervene What to assess Potential complications The ‘Rules of Calvings Presentations Uterine torsions Fetotomy Caesarean surgery Uterine prolapse Stages of labour • 1st stage labour - dilation of the cervix (may take 3-6 hours) • The cow separate herself from herdmates • Her appetite will decrease • She may frequently alternate between lying and standing • A thick string of mucus is often seen hanging from the vulva • Towards the end bouts of abdominal straining occur more frequently, usually every 2-3 minutes • The abdominal straining pushes uterine contents against the cervix giving it further stimulation to dilate Stages of labour • 2nd stage labour – delivery of the calf • This stage begins with the appearance of membranes (water bag) at the vulva • This stage may last several hours • Water bag ruptures with a sudden rush of fluid • Cervix dilates with further pressure from calf • Powerful reflex and voluntary contractions of abdominal muscle and diaphragm ("straining") serve to expel the calf Stages of labour • 3rd stage labour • Expulsion of the placenta • Usually happens relatively quickly, within a few hours • Retained fetal membranes (RFM) if not expelled within 12 hours after delivery of the calf Ideal calving facilities Optimum is an individual pen 12 feet x 12 feet+’ Cows like to calve alone Easy to clean out in between calvings to provide excellent hygiene A gate +/- a quick release headlock Allows one worker to easily catch a cow for close examination or to assist in the calving process Milking facility Overhead vacuum line or mobile milking machine Well bedded and dry Good access to food and water Good lighting Well ventilated and in a well located quiet area of the farm Plan of an ideal calving box? An ideal calving box When to intervene Intervention too early when the cow is in 1st stage labour can prevent full dilatation of the cervix Only intervene if: no progress has been made by the cow after 1 hour of the water bag starts showing if you thought she was showing signs of 1st stage labour but has not progressed to 2nd stage after 6 hours – possible twisted uterus she appears in extreme discomfort there is significant bleeding from the vulva Normal presentation Dystocia • Causes? Dystocia Causes: 1. Malpresentation 2. Foeto-maternal oversize • • • • Large calf Fat dam Young/poorly grown dam Dead emphysematous calf 3. Congenital abnormality • • • Schistosoma refluxus Spina bifida Hydrocephalus 4. Hydrops allantois 5. Schmallenberg Virus 6. Primary inertia • Hypocalcaemia Dystocia Diagnosis: 1. History • • • • Age/parity; breed of dam; breed of sire; previous problems How long been straining? Attempts made by farmer & for how long Water bag broken? When? 2. General impression • Cows attitude; BCS; behaviour 3. General examination (if indicated, e.g. recumbent and not bright / bloated. Check udder) • hypocalcaemia 4. Obstetrical examination • • • Vulva slackened; evidence of membranes from vulva Vaginal examination Rectal examination (if indicated) Vaginal examination Pay particular attention to: 1. 2. 3. 4. 5. 6. Lesions (tears) or haemorrhage Position of uterus and calf Relaxation and dilatation of vulva, vagina, cervix Signs of life from calf Possibility of extraction Position of umbilical cord (particularly with breech presentations) Dystocia - approach • • • • • Restrain Clean Lubricate Identify 3R – Reposition (calf or uterus) – Repulsion – Rotation • Extract! Cunning tricks ! • Position cow “downhill” (or uphill) • Best lubricant = J-lube • Pump warm water & lube into uterus – Fill her up ! – makes space • Sink plunger for repulsion • Epidural anaesthesia • Clenbuterol – relaxes uterus – but she won’t help in delivery – increases uterine blood perfusion – calf survival? Phone a (friend) colleague: You should have backup whilst on call until you are confident / capable – need to stay in control If the cow does not fit the ‘rules of calving’ it is too big and need a caesarean You find a true breech You suspect a twisted uterus You can’t make sense of what you feel in the vagina You find lots of bleeding You don’t make any progress within 20 minutes of trying to calve her/correct a malpresentation Vet Record. 1978 102(15):327-32. Quantification of obstetric traction. Hindson JC. Vet Record. 1978 102(15):327-32. Quantification of obstetric traction. Hindson JC. Vet Record. 1978 102(15):327-32. Quantification of obstetric traction. Hindson JC. Vet Record. 1978 102(15):327-32. Quantification of obstetric traction. Hindson JC. Hindson Ratio Vet Record (2007) 161(20):685-7. Economic cost of difficult calvings in the United Kingdom dairy herd. McGuirk BJ, Forsyth R, Dobson H. Rope/Chain placement Above fetlock versus Below fetlock • • Above = higher risk of leg fracture Below = higher risk of rope slipping off • Double loop = minimal chance of leg fracture or rope slipping off • One loop above fetlock, 2nd below Trial extraction Rules for decision making – standing cow Anterior presentation • The head should be easily lifted into the pelvis, and remain there and not flop back into the uterus • If the forelimbs are crossing over there is insufficient room for calving per vaginum, as the cows pelvis is putting pressure on the humeri and the width of the shoulder is too large • Should be able to easily (traction by one person) bring the calf up so the fetlocks are a hands breadth out of the vulva. This means the shoulder is within the pelvic canal. Failure to achieve this means the calf is too big to be extracted per vaginum Malpresentations – carpal flexure Malpresentations – carpal flexure correction Rules for decision making – standing cow Posterior presentation • Assess space by sliding hand over tail head • Two people should be able to exteriorise the limbs to the point at which the hocks are past the vulva. Failure to do so rules out calving per vaginum • Check position of umbilical cord. Could be round hock. If so then as you pull calf break cord and calf may die/drown before you get it out. Advice farm of risk. Could do caesarian section or calve and take the risk. FACULTEIT DIERGENEESKUNDE Correction of breech presentations Episiotomy Uncommonly used in cattle • Almost totally reserved for heifers • In HF heifers 5-10% may need episiotomy Narrow vestibulum and vulva • Vulva not fully slackened and dilated BUT cervix dilated and calf entering pelvic canal Try manually stretching vulval lips with arms for ~20 minutes before resort to episiotomy Perineum area contamination risk HIGH – requires antibiotics to help prevent breakdown Caudal epidural anaesthesia Episiotomy Cut at 10-11 o’clock OR 1-2 o’clock position • Controlled cut, rather than tear vulva during traction • Make incision when calf’s head passing through vulva Episiotomy – suturing technique • Interrupted deep dissolvable sutures • Interrupted or continuous skin sutures Episiotomy – complications Wound infection and breakdown Distorted vulva conformation • Pneumo-vaginum • Uro-vaginum • Poor conception rates Weak point to muscles which may affect ability to calve naturally in the future Cut at 12 noon = Rectovaginal fistula Embryotomy / Foetotomy method MUST HAVE SUFFICIENT SPACE WITHIN THE VAGINA AND PELVIC CANAL FOR EMBRYOTOME & ARMS! Caudal epidural anaesthesia Clenbuterol Sufficient lubrication to facilitate movements required Good equipment, well maintained Embryotomy / Foetotomy indications Full embryotomy/fetotomy: • Large dead calf • Abnormal calf – i.e. foetal monster Partial embryotomy/fetotomy: • Hip locked • • • • • Head back - unable to correct and calf dead • • Euthanase if still alive Cut off trunk as close to vulva as possible Pass wire to split pelvis Repulse one hind-quarter and remove the other Remove head – using ‘passing’ method Leg back – unable to correct and calf dead • • Remove leg using passing method MUST ensure elbow, shoulder and scapula are removed otherwise no narrowing will be achieved Embryotomy / Foetotomy method Methods of placing wire: ‘Passing’ • • • Pass wire by hand around the appendage/area of calf needing removal Where appropriate attach a curved snare director or another form of weight Thread the wire through each side of the embryotome, tighten, check wire in correct place by palpation before sawing ‘Cleat’ • • • • • • Place an obstetric chain on the limb in question Thread the wire through the embryotome Place the loop of the wire in-between the cleats on the leg aiming to remove Advance the embryotome laterally up the limb to just past the top of the scapula/anterior aspect of the greater trochanter Unhook the wire from between the cleats, pass the obstetric chain through the loop, to allow the wire to be tightened up the medial aspect of the limb to lie in the auxilla or between the hindlimbs Check the position of the wire before sawing Embryotomy / Foetotomy – ‘cleat’ method Removal of the head Assuming a normal presentation: 1. Remove head using ‘passing’ method of wire placement 1. Cut as far caudal along neck as possible 2. Embryotome placed lateral or ventral – space allowance will dictate this 3. Avoid cutting cervix or vaginal wall Fetotomy – removal of forelimb Ensure entire scapula removed Care not to cut through humerus – this will lead to sharp bony edges, and will not have narrowed the calf width at all. Fetotomy – removal of thorax 3. Using the obstetric hook advance the trunk 4. Remove as much of the trunk as possible using the ‘passing’ method of wire placement • Remove as many vertebrae as possible in one cut Assuming a normal presentation: 5. Pull/cut out any parts of the GI tract interfering with your ability to feel the remnants of the foetus 6. Remove the rest of the trunk (if necessary) to leave just the hind quarters Assuming a normal presentation: 7. Split the pelvis, using the passing method of wire placement • • Pass the wire over the tail head with either a curved snare director or another weight Re-gather wire from between hind legs 8. Extract one hind limb at a time Assuming a normal presentation: 9. Check for a twin 10. Check for damage to the uterus (as far in as you can feel), cervix and vagina and treat accordingly Remove foetal membranes if possible Anti-inflammatory and antibiotic therapy are advised Fetotomy complications Uterine tears Cervical tears Vaginal tears - from sharp bone edges - from incorrect, rough handling of embryotome RFM Metritis Adhesions Uterine torsions Most torsions occur at the onset of parturition, rather than during pregnancy Risk factors: • Poor rumen fill • Space in the abdomen • Hilly land • Process of standing up/lying down Majority are anti-clockwise torsions (when stood behind cow) Varying degree of torsion - 90̊ to >360̊ Uterine torsions Presentation: • • • • Appear to start calving but do not progress No straining as Ferguson’s reflex not stimulated May just see slightly raised tail Dry cow off colour/down/toxic Examination findings: • • • • Vaginal exam causes arm to ‘corkscrew’ (normally anticlockwise) May just feel a ‘lip’ in front of cervix May not be able to feel cervix or calf (depending on degree of torsion) Exam per rectum - palpation of the torsion Uterine torsions Correction methods: • ‘Swing’ calf with coordinated ballottment of abdomen to flip the calf and uterine horn back into the correct position • MUST be able to reach and firmly grasp calf by hand or with a rope • Twist legs of calf and uterus may twist too – esp. if calf upside down • Use arm, broom stick, • “gyn-stick” http://www.vetsonic.co.uk/cattle.html • https://www.youtube.com/watch?v=w1thouALmqY • Roll the cow • Majority of cases require cow to be rolled from left lateral recumbency, onto her back, and into right lateral recumbency • If calf can be reached, grasp a leg firmly or place a calving rope and be held firmly whilst the cow is rolled over • If the calf cannot be reached, a plank can be placed across the abdomen and weighed down to apply pressure to the abdomen whilst the cow is rolled • Caesarian section • Unable to untwist uterus Uterine torsions Complications: • • If high degree torsion, the blood supply can be occluded leading to very friable tissue at the site of the torsion If not noticed early can lead to a dead emphysematous calf and a toxic cow During Caesarian uterus can be difficult as untwists away from you when suturing Reuff’s method to cast a cow youtube www.youtube.com/watch?v=AWPn0QuJ1ok http://www.youtube.com/watch?v=H7zQQx4BZlQ Plank technique Caesarian section indications Forced: Major indications: 1. Foetal oversize/foeto-maternal disproportion 2. Irreducible uterine torsion 3. Insufficient cervical dilatation Minor indications: 4. Foetal malpresentaion • ONLY as a last resort if unable to reposition 5. Abnormal calf • Where embryotomy/foetotomy not feasible 6. Dead/empyhsematous calf • Where embryotomy/foetotomy not feasible 7. Constricted vagina and vestibulum • Where massage has not releaved the constriction Elective: Double muscled breeds, Embryo transfer calves Caesarian section technique Adequate restraint • • • Halter tied to gate Stocks Head yoke/full access crush • Sedation • Secure the tail to the leg to avoid wound contamination • MUST be able to safely remove animal from restraint system should the cow go down • AVOID unless unsafe to perform surgery without Anaesthesia • Caudal epidural • • • Paravertebral nerve block (Inverted L nerve block) (Line block) • Block Ferguson’s reflex Caesarian section technique Pre-op medication • • • • • Tocolytic (Clenbuterol) NSAID Antibiotic? Sedation? Calcium • Where clinically appropriate Additional considerations • • Adequate lighting Standing/down in right lateral recumbency • If standing MUST stay up • Place a rope on right hindlimb and pass under abdomen – if begins to go down pull rope to ensure falls away from wound • If down MUST stay down • • High volume caudal epidural Sedation Caesarian section technique 1. Left flank approach Clip and sterile preparation of the left flank Incise: From 1 hands breadth below transverse processes 1 hands breadth behind last rib Approximately the length from the tip of your finger to point of your elbow Vertical incision or angled incision 2. Locate uterine horn containing calf and exteriorise 3. Incise uterus If normal presentation incise greater curvature from point of hock to tip of toe If breech presentation incise greater curvature from carpus to tip of toe AVOID cutting placentomes – ligate any bleeding caruncles Blade/Kruuse knife (guarded blade)/scissors 4. Remove calf Locate umbilical cord & ensure not torsed, prevent early rupture and rupture too close to the body wall on extraction If incision appears too small extend in a controlled manner rather than allowing to rip Assistant to attend to calf L flank clip/shave & disinfect drapes vertical incission long enough incise muscle layers and peritoneum explore abdomen & exteriorise leg hock – cupped in hand foot incise uterus & membranes Deliver calf suture uterus – 2 layers (inverted) (over-sow) Caesarian section technique 5. Check for a twins, and triplet 6. Remove foetal membranes 7. Close uterine incision Absorbable Ideally monofilament Round bodied needle Inverting pattern 1 or 2 layers Bury knots Ensure no leakage 8. Clean off contamination from uterus, rumen and remove blood clots from the abdomen 9. Routine closure of body wall and skin Application of antibiotics to the muscle layers when closing has been shown to reduce the risk of wound infection 10. Post-op medication Oxytocin Calcium (if clinically appropriate) 11. Check calf & ensure sufficient colostrum provided close her up suture muscle and peritoneum in 2 layers suture skin “tack” layers together to eliminate deadspace emphysematous calf paramedian incision very low flank incision exteriorise horn sedation/drop large epidural – 50 ml zylazine zylazine & ketamine chloral hydrate (not in UK) useful tools a few tips! if cannot easily exteriorise open uterus in situ with Kruuse knife incise Greater Curvature only (check) posterior presentation Cannot easily exteriorise use Kruuse knife get head out of uterus first before legs otherwise head “goes back” requiring very large uterine incision Caesarian section complications • Haemorrhage • • • • Re-open, locate site of bleeding and ligate Peritonitis • Post-op check next day may reveal off colour cow, pyrexia • At 7 days post-op become palpable on rectal examination • Re-open, identify any site of leakage, flush abdomen with sterile fluid • Poor prognosis Localised adhesions – may detect at post natal check • • • • • Post-op check next day may reveal off colour cow, tachycardia/murmur, palor Ovarian Uterine Retained foetal membranes Metritis Wound infection/seroma/breakdown/emphysema Caesarian section complications Poor fertility due to: Delayed uterine involution RFM Endometritis Salpingitis Adhesions Abortion Evidence suggests 80-85% of cows should rebreed An early decision that a Caesarian is necessary will improve success rates Uterine prolapse Uterine prolapse • • • • • • Hypocalcaemia Bladder 2 week survival 80% (better if live calf) 50 days increase in calving to conception Methods Rules! Uterine prolapse Cow standing or down in sternal with hindlimbs extended out behind her Replacement technique: 1. Caudal epidural anaesthesia +/- clenbuterol 2. Put protective cover under uterus 3. Remove foetal membranes and clean off contamination 4. Apply liquid lubricant and gradually feed uterus back in • • AVOID using finger tips – may rupture uterus EITHER feed in in section starting close to the vulva or evert from horn tips 5. Once replaced ensure horn tips fully everted by using a bottle to extend the reach of your arm, or fill the uterus with water 6. Give oxytocin, NSAIDs, antibiotics, calcium 7. If swollen sugar or salt have been used. Gentle pressure and support? 8. Place Buhner suture ?????? In Practice. 1986 Jan;8(1):14-5. Prolapse of the uterus in the cow. Plenderleith B. Tim Potter UK Vet - Vol 13 No 1 January 2008 Summary • Dystocia most commonly caused by malpresentations or size disproportion between the foetus and dam • Decision making rules should allow rapid choices to be made, with the best outcome • An early decision to perform a caesarian will result in the best outcome • Exteriorisation of the uterus before incising to minimise abdominal contamination will reduce the risk of peritonitis • A water tight closure of the uterus is essential • Application of antibiotics onto the muscle layers during closure reduce the likelihood of wound infection • Embryotomy/fetotomy may only be undertaken where there is sufficient space in the vagina and pelvic canal to safely perform the procedure • Uterine prolapses are true emergencies • The use of caudal epidural anaesthesia will vastly aid the replacement of a prolapse • Episiotomies should not be undertaken lightly, and used only when persistent attempts to manually dilate the vestibulum and vulva have failed Dystocia - approach Restrain Clean Lubricate Identify Repel Reposition Extract! After Calving • A difficult calving is a risk factor for many diseases. • Check that the last stage of labour – expulsion of membranes occurs. • Check / encourage her to eat and drink • If she is bruised or torn consider if need Antibiotic. • Consider giving pain relief – NSAID • Cold hose back end to reduce swelling? • She is at risk or endometritis so keep an eye on any discharges and get her checked out • Be pro-active to avoid problems developing Things can go wrong – calf post mortems! References and links • • • • • • • www.drostproject.org Cabell E. (2004) Approach to dystocia in the cow Part 1: Anterior and posterior presentations. UK Vet, Volume 9 No. 2, March 2004;1-4 (on VITAL) Cabell E. (2004) Approach to dystocia in the cow Part 2: Common malpresentations and uterine torsions. UK Vet, Volume 9 No.5, September 2004;46-49 (on VITAL) Cabell E. (2004) Caesarian techniques for the vertically challenged. UK Vet, Volume 9 No. 6, October 2004;41-44 (on VITAL) Hoeben D, Mijten P & deKruif A. (1997) Factors influencing complications during caesarian section on the standing cow. Vet Quarterly 1997; 19; 8892 Kolkman I, de Vliegher S, Hoflack G, van Aert M, Laureyns J, Lips D, de Kruif A, Opsomer G. (2007) Protocol of the caesarian section as performed in daily bovine practice in Belgium. Reproduction of Domesic Animals: 42; 583-589 Wapenaar W, Griffiths H, Lowes J, Brennan M. (2011) Developing Evidence-based Guidelines Using Expert Opinion for the Management of Uterine Prolapses in Cattle. (2011) CATTLE PRACTICE; MAR, 2011; 19; p17-p21