Pulse oximetry and cardiorespiratory changes during upper gastrointestinal endoscopy in dogs

The objective of the present study was to determine the changes in heart rate, respiratory rate and arterial Oxygen saturation (SpO2) by administration of three drug combinations during upper gastrointestinal endoscopy. Design: Experimental study. Animals: 21 healthy and adults dog were randomly divided into three groups. Procedures- The IV combination of 6.5 mg/kg ketamine and 0.2 mg/kg diazepam was administered in group KD and 6.5 mg/kg ketamine and 0.3 mg/kg midazolam and 6.5 mg/kg ketamine and 0.4 mg/kg medetomidine were used in group KMi and KMed respectively. Respiratory rate/min, heart rate/min and SpO2 were recorded prior to induction of anesthesia and during endoscopy in esophagus, cardiac level, cardia and during exertion. In addition time to induction of anesthesia and duration of anesthesia were recorded in all dogs. Time to induction of anesthesia and duration of anesthesia were significantly shorter in group KMi compared to group KD and KMed (P<0.05). All of the dogs were suffered from hypoxia. However the changes were significant in groups KD and KMi (P<0.05). Conclusion and Clinical Relevance: All combinations of the drugs produced hypoxia, however the hypoxia was less when the combination of ketamine and medetomidine was used.Oxygen supplementation is recommended during upper gastrointestinal endoscopy in dogs to prevent hypoxia.