Serial paired arterial and jugular venous point-of-care values in dogs undergoing manual basic life support

Abstract

Objective

To evaluate differences in point-of-care (POC) variables obtained from arterial and jugular venous blood in dogs undergoing manual basic life support (BLS) and report changes over time.

Design

Experimental study.

Setting

Small animal research facility.

Animals

Twenty-four purpose-bred research dogs.

Interventions

Dogs were anesthetized, and arterial catheters were placed before euthanasia. One minute after cardiopulmonary arrest, BLS consisting of manual chest compressions and ventilation delivered via endotracheal intubation, face mask, mouth-to-nose, or no ventilation was initiated. Paired arterial and jugular venous blood samples were obtained for POC testing before euthanasia (T₀), at 3 minutes (T₃), and at 6 minutes (T₆) into BLS.

Measurements and Main Results

The association of POC variables with arterial or venous sample type while controlling for type of ventilation and sampling timepoint was determined using a generalized linear mixed model. Variables obtained from arterial and venous blood samples were compared over time using repeated measures ANOVA or Friedman test. Pao₂, anion gap, potassium, chloride, glucose concentration, and PCV were significantly higher in arterial blood samples compared with venous samples (P < 0.03). By T₆, arterial glucose concentration, arterial and venous base excess, venous pH, and plasma lactate, potassium, creatinine, bicarbonate, and sodium concentrations were significantly increased, and arterial and venous Po₂, ionized calcium concentration, PCV, and total plasma protein concentration were significantly decreased from T₀ (P < 0.05).

Conclusions

Although statistically significant, arteriovenous differences and changes in POC blood variables during BLS were small and not clinically relevant over time. Given the challenges of arterial blood sampling, it may be reasonable to pursue venous blood sampling during CPR. Further studies in dogs undergoing BLS and advanced life support are needed to better understand the potential clinical role of POC testing during CPR.