Plus-Hex CLINICAL site can then be clipped ( if this has not already been done ), followed by sterile skin preparation . The clip should be around the same size as that for an exploratory laparotomy , to include xiphoid to pubis and lateral to the mammary glands . Care should be taken by the VN when clipping and scrubbing the patient as these breeds are predisposed to skin allergies .
General anaesthetic monitoring
Once prepared , the patient should be moved to the surgical table , which should ideally be tilted upwards 10 – 15 degrees at the cranial end to reduce pressure on the diaphragm . Anaesthesia should then be maintained via isoflurane or sevoflurane titrated to the lowest level of effect . Gold standard monitoring of the brachycephalic c-section should include an electrocardiogram ( ECG ), blood pressure , pulse oximetry , and end-tidal carbon dioxide ( ETCO 2
), as well as routine monitoring by the VN and recording of parameters every 5 minutes . It may be useful to use AVA ' s ASA high-risk-anaesthetic monitoring chart ( Appendix 1 ) [ 10 ] .
Where possible , there should be an allocated VN to monitor the anaesthetic and a separate team to resuscitate the pups . This will ensure any anaesthetic problems in this high-risk anaesthetic are picked up immediately . For example , decreased systemic blood pressure will affect the pups by indirectly reducing foetal oxygen delivery . As a precaution , intravenous crystalloid fluid therapy should ideally be started preoperatively , but unresponsive hypotension may require an ephedrine bolus ( 0.03 – 0.1 mg / kg ) administered intravenously . This is used off-licence to raise blood pressure and maintain uterine blood flow [ 4 ] . A notably higher ETCO 2 and rebreathing caused by hyperventilation may be seen in brachycephalic patients , causing a fractional increase of inspired carbon dioxide . This may be controlled with a higher fresh gas flow rate of oxygen and ventilation by the VN . Bradycardia may present on the ECG shortly after intubation or a change of recumbency , stimulated by the susceptibility of brachycephalic dog breeds to an increased vagal tone [ 11 ] .
Analgesic drugs should be administered once all of the pups are out . This allows enough time for them to take effect prior to recovery and will allow the bitch to bond with the pups more comfortably when they are suckling [ 12 ] . Oxytocin may also be administered just before recovery to assist with milk production .
Neonatal resuscitation
Delivery by c-section does not allow for the natural chest compression of the neonates that occurs with vaginal delivery . This would usually stimulate the neonates ' breathing through the recoil of the chest wall during birth , which aids in expelling fluid from the respiratory tract . Neonates delivered by c-section therefore require vigorous rubbing to stimulate respiration . Ideally , there should be one VN for each pup .
An immediate resuscitation protocol should begin by removing the foetal membranes and vigorously rubbing the pups with warm towels . Fluid should be manually cleared from the nasal and oral cavity . The traditional practice of swinging pups to clear fluid is now discouraged as it risks causing significant brain trauma [ 13 ] .
The pups ' umbilical cords should be ligated at least 1 cm from the body wall to prevent haemorrhage . After this , VNs should focus on thermoregulation of the pups . Once dried off with towels , the pups can be placed in a warm whelping box or incubator at around 30 – 32 ° C , provided they are breathing and vocalising [ 14 ] . Oxygen supplementation can still be supplied , if required .
Neonates must be assessed quickly , as these breeds tend to have decreased vigour compared with nonbrachycephalic breeds . Brachycephalic neonates should be regularly scored using the Apgar scoring system to detect neonatal distress rapidly , allowing prompt intervention ( Table 1 ) [ 15 ] . Abnormalities such as orofacial clefts , umbilical hernias , anasarca ( water babies ), swimmer puppy syndrome , pectus excavatum , and pulmonary stenosis are frequently reported in these breeds [ 16 , 17 ] .
Table 1 . Apgar scoring for canine newborn viability evaluation [ 15 ] . Lower scores indicate greater neonatal distress . bpm = beats per minute .
Parameter Score ( 0 – 2 )
0 1 2 Heart rate < 180 bpm 180 – 220 bpm > 220 bpm Respiratory effort
< 6 breaths / min No crying
6 – 15 breaths / min Mild crying
> 15 breaths / min Clear crying
Reflex irritability Absent Grimace Vigorous Motility Flaccid Some flexions Active motion Mucous membrane colour Cyanotic Pale Pink
Volume 38 ( 4 ) • August 2023
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