Efficacy of Manual Ventilation Techniques During Cardiopulmonary Resuscitation in Dogs

Abstract

The efficacy of ventilation of dogs during cardiopulmonary resuscitation (CPR) with a tight fitting face mask or mouth-to-nose rescue breathing has not been evaluated. Twenty-four purpose bred research dogs: Dogs were randomized to be ventilated by cuffed orotracheal tube, tight fitting face mask, mouth-to-nose breathing or compressions only during CPR (n = 6 in all groups). Orotracheal tube and face mask ventilation was performed on room air. Chest compressions were performed during the experimental procedure. Arterial blood gases were performed prior to euthanasia (baseline), at 3 min and at 6 min of CPR. PaO2 and PaCO2 were compared for each time point and each group. There was no difference in PaO2 or PaCO2 between groups at baseline. At 6 min all groups had a significantly higher PaCO2 (P ≤ 0.005) and the facemask and compression only groups had a significantly lower PaO2 (P < 0.02) when compared to the orotracheal tube group. There was no difference between the PaO2 of the mouth-to-nose group compared to the orotracheal tube group at 3 or 6 min. Gastric distension, regurgitation, gas leakage around the mouth, and ineffective breaths were all noted in both the face mask and mouth-to-nose group. The results of this study supports that orotracheal intubation is the preferred technique for ventilation during CPR in dogs. When orotracheal intubation is not possible, face mask ventilation or mouth-to-nose ventilation would be reasonable alternatives. When oxygen supplementation is available, face mask ventilation is likely to be superior. Appropriate training for both face mask and mouth-to-nose ventilation techniques is recommended.

Behavioural risks in female dogs with minimal lifetime exposure to gonadal hormones

“…The reasons for gonadectomy in dogs vary, but the procedure is most commonly encouraged as a means of population control; historically being conducted at, or just before, sexual maturity. Gonadectomy has also been recommended in some countries as a means of preventing medical and behavioural problems [23,24]. In recent times, the benefits of early-age gonadectomy (at less than 12 weeks of age) for population control have been emphasised [25].…”

“…For example, spayed female golden retrievers had a 3–4 fold increase in the rate of some cancers [23]. Similarly, studies of golden retrievers [24] and German shepherd dogs [25] indicate that early neutering can significantly predispose dogs to joint disorders, including hip dysplasia.…”

“…Recent studies have identified some concerning and surprising trends. For example, gonadectomised dogs of both sexes have been reported to be marginally more prone to aggression towards unfamiliar humans than entire dogs [24]. Weight gain and related lethargy are seen in many gonadectomised dogs [68], and a metanalysis of studies designed to determine the maintenance energy requirements of dogs found that maintenance energy requirements were much less in neutered dogs [62].…”

“…Recent studies of male dogs have revealed behavioural risks associated with minimal lifetime exposure to gonadal hormones that may offset some population-control benefits of gonadectomy [24,31]. The current study examines data from the owners of female dogs to explore relationships between various canine behavioural attributes, as reported through C-BARQ, and the timing of spaying considered as both age-at-spay (AAS) and percentage lifetime exposure to gonadal hormones (PLGH).…”

A Proposed Guideline for Performance of Emergency Surgical Airways in Small Animals: Analysis of Five Unsuccessfully Managed Cannot Intubate, Cannot Oxygenate Cases

“…Cannula airway access is also not ideal during CPR compared with endotracheal intubation due to lack of a tube cuff sealing the airway, which is likely one of the reasons case 4 had the cannula tracheostomy immediately converted to a tube tracheostomy. It is impossible to provide effective ventilation or oxygenation against the force of a chest compression without adequate sealing of the airway [21]. Another reason favouring tubes over cannulas during CPR is improved monitoring.…”