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Bovis ISSN 2398-2993 Cesarean Section Synonym(s): Surgical management of dystocia in cattle. Contributor(s): Paul Wood, Adam Martin Introduction • This article describes the technique used to perform a cesarean section and discusses the decision making processes involved in determining when a cesarean section is appropriate. • Please be aware that this information is designed to be a useful guide for the veterinary surgeon, but is not prescriptive. The decision making process will very much depend on the individual case and its unique circumstances. Uses Maternal dystocia • Expulsive defect/: - Myometrial defect: > Primary uterine inertia (inability of uterus to contract sufficiently). > Secondary uterine inertia (decreased effectiveness of uterine contractions as parturition progresses). -Defective or inadeqate straining. • Inadequate birth canal: - Failure of cervix, soft tissues or ligaments to relax. - Uterine torsion; definitely if complete torsion (>2700). - Obstruction of birth canal, eg pelvic fracture. • Inadequate pelvic diameter* Fetal dystocia • Fetal oversize: - Normal but large*. - Defective or monster calf. • Faulty disposition or alignment: - Abnormal presentation. - Abnormal position. - Abnormal posture. • Fetal death. • Signs of fetal distress. *these two factors combined or separately can be described as fetomaternal disproportion. Elective cesarean • History of previous dystocia or cesarean. • Predictable dystocia due to breed predisposition, eg Belgian blue cattle or misalliance, eg heifer too small when mated. Advantages of performing the procedure • Increased chance of live calves if intervention performed early. • Reduced chances of secondary complications to cow, eg peripheral neuropathies. Disadvantages • Cost. • Risk of surgical and post-surgical complications in dam, including death. • May reduce subsequent fertility of dam. • Anesthetic depression of calf (if sedative used). Alternative techniques Alternative treatments for inertia • Manipulation if reducable malpresentations. • Manual traction of fetus. • Correction of uterine torsion. • Fetotomy/embryotomy if calf is dead. Time required Preparation Assessing the situation • Obtain a history for the dam: - Expected due date. - Primigravida vs multigravida. - Problems during pregnancy. - When were signs of first stage labor seen? - What has the farmer observed since? - What has the farmer done so far? - Has the cow recieved any treatments? - What are the farmer’s expectations/needs? • Assess dam general status. • Assess presentation, postion and posture of calf. • Assess viability of calf. • Assess environment for performing necessary procedure. - Safe. - Adequate lighting. - Cleanliness. - Good footing. - Area to safely restrain cow. Once decision to perform cesarean made • Administer Epidural (if not done already for assessment of fetus). Procedure • 30-90 minutes. • Procedure should be performed as quickly and safely as possible. Decision taking Criteria for choosing test • Assessment of cause of Dystocia. • History suggestive of fetomaternal disproportion. • Presence of uterine inertia. • Decision often a subjective assessment of the dam and calf status and experience of the veterinary surgeon. • Value of calf vs value of cow may play a deciding role. Diagnosis of Dystocia • Hugely variable gestation lengths between breeds and sires. • Records not always reliable, particularly in beef systems. • Intervention in cows: - Stage two labor lasting for greater then one hour. - There are a lot of conflicting statements in the literature, as to the normal length of stage 2 labor. > Published lengths range from 1-2 hours (heifers), 0.5 – 1.5 hours (cows) to some that say normal stage 2 in cows should be less than an hour. There is also some literature which considers earlier intervention as a producing a better outcome for cow and calf. > The advice here reflects the author’s personal opinion and cases should be assessed on an individual basis. Emphasis should be on noticing whether the labor is progressing, over the time period in question. • Intervention in heifers: - No significant progress made after 30 minutes of appearance of fetal membranes. • General reasons for intervention: - Weak or infrequent abdominal straining. - Absence of abdominal straining. - Obvious fetomaternal disproportion or obstruction. - Signs of systemic illness. - Evidence of fetal death. - Meconium visible as vulval discharge. Risk assessment • Risk of fetal death. • Risk of cow death. • Safety of environment for performing procedure. Requirements Personnel Veterinarian expertise • The veterinary surgeon needs to be confident in their abilities to: - Diagnose dystocia. - Perform anesthesia (general or local). - Perform this surgery confidently. New graduates should not be expected to perform this surgery without supervision. Anesthetist expertise • Veterinary surgeon may be required to perform some of the following anesthetic tasks: - Sedation. - General anesthesia. - Epidural Epidural. - Line block Line block. -Inverted L block. - Paravertebral blocks. > Proximal block (Farquharson method). > Distal Block (Magda method). Nursing expertise • The farmer or an assistant should be aware of the requirements for dealing with the neonatal calf once it is removed. Print out the farmer information sheet on: Caring for the cow and calf post cesarean. Other involvement • The farmer should be aware of the requirement to not touch the surgical field unless ade- quate surgical preparation of their person has been performed. Materials required Minimum equipment • Halter or other restraint. • Clippers or razor. • Surgical scrub. • Surgical spirit. • Clean/Surgical waterproof clothing. • Surgical kit. Ideal equipment • Sterile gloves.
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