bull dog caesarian anaesthesia
TRANSCRIPT
Anaesthesia for English Bulldog Caesarean Section
Rachel Brown Justine Dooey
Stephanie Harmon
Case Details
6 year old English Bulldog
20 kg bodyweight
Heavily pregnant
2 hours unproductive straining
Caesarian section required
Main Considerations Brachycephalic
Pregnant
Pups
Brachycephalic Breed
Brachycephalic Obstructive Airway Syndrome Stenotic nares Elongated soft palate Hypoplastic trachea Everted laryngeal saccules
Increased Risk of Regurgitation and Aspiration
Effects of Pregnancy on Bitch
Cardiovascular Increased cardiac workload Aortocaval compression → supine hypertension
Respiratory Decreased total lung volume and function Higher O2 demand to CO2 production Rapid desaturation → hypoxaemia
Gastrointestinal Delayed gastric emptying with decreased oesophageal sphincter tone
Neurological ~35% increased sensitivity to anaesthetic agents
Changes in Progesterone and Beta Endorphin levels have Sedative Effects
Haematology Decreased HCT
Anaesthetic Effects on Pups In Utero
Placental transfer of drugs to pups Cross the blood-brain barrier Respiratory Depression Hypotension Bradycardia
Drug transfer from milk• (Little research in dogs)
Anaesthetic Aims
Be cautious of drug overdosesDecrease drug exposure timeIncrease drug elimination rateMaintain hydration and blood pressureMaintain oxygenationProvide analgesia without affecting pupsRapid recovery to decrease respiratory
complicationsMaintain airway
Anticipated Complications
Hypotension Provide I.V. fluids Keep isoflurane concentrations at a minimum
Bradycardia Keep isoflurane at a minimum
Hypoxaemia Provide 100% O2
Hypothermia Bair hugger
Anaesthetic plan
Try to Avoid Pre-Medication but if Necessary Acepromazine I.M.
0.01mg/kg = 0.2mg= 0.1ml Pethidine I.M.
2mg/kg = 40 mg = 0.8mls Pre-oxygenate 3-5 mins before induction Surgical clip and prep whilst awake in lateral recumbency
Induction Propofol I.V.
4mg/kg = 80mg; 10mg/ml; draw up 12ml Fast Intubation with cuffed tube – smaller ET tube than expected
Maintenance Bain breathing system; Isoflurane and O2 4L/min
Isoflurane MAC decreases 40% in pregnant animals IVFT 10ml/kg/hr = 200ml/hr Hartmann’s
Analgesia
Midline Local Anaesthetic Block 50% Lidocaine:Bupivacaine Intradermally
4mg/kg = 80mg = 4ml 1mg/kg = 20 mg = 4ml
When Last Pup Out Methadone 0.2-0.5mg/kg 0.4-1ml I.M. Meloxicam 0.2mg/kg = 0.8ml S.C. – One off dose
Post Operative Care & Analgesia
Bitch Keep ET tube in until fully awake to maintain airway Methadone every 4 hours as needed for pain
1mg/kg = 20mg = 2ml S.C. Send home on Tramadol (not licensed)
2-5mg/kg 2-3 times daily
Pups Assess every 30 seconds Prevent hypothermia Provide 100% O2 Mask or ET intubation if no spontaneous breathing
References
Vullo, Cecilia, et al. "Anesthetic Management during Cesarean Section in English Bulldogs." Journal of Life Sciences 8.1 (2014): 58-64. http://www.davidpublishing.com/davidpublishing/Upfile/5/27/2014/2014052708753330.pdf
D. Flaherty, Anaesthesia for caesarean section BVMS 4 University of Glasgow Lecture.
PREGNANT TIPS | PREGNANCY GUIDE. (n.d.). Retrieved April 30, 2015, from http://pregnancy.pregnantshop.info/8-week-pregnant-english-bulldog
Pricing for our English Bulldogs. (n.d.). Retrieved April 30, 2015, from http://www.bulldozeenglishbulldogs.com/Pricing.html