Oxygen Reserve Index as a Tool to Monitor Four Techniques of Oxygen Supplementation at Different Flow Rates in Dogs Sedated with Dexmedetomidine and an Opioid

Abstract

Respiratory dysfunction often decreases arterial oxygen content. Four common oxygen delivery techniques—flow-by, nasal prongs, a tight-vented mask, and a tight mask connected to a Venturi valve—were evaluated for their effectiveness in increasing the oxygen reserve index (ORi), a dimensionless index of oxygen content that provides additional information compared to traditional pulse oximetry (SpO2) during hyperoxia (PaO2 100–200 mmHg), and that ranges from 0 to 1. Thirty-two dogs sedated with dexmedetomidine and an opioid were evenly divided into four groups based on the technique for oxygen administration. Each dog received oxygen at 1, 2, and 3 L/min by a single technique, and the amount of inhaled oxygen (FiO2) was measured at the level of the cervical trachea. At each flow rate, ORi and SpO2 were recorded. The flow-by method minimally increased the FiO2, and ORi reached its highest value only in 3 out of 8 dogs at the maximum flow rate. Other methods exhibited direct correlations between the oxygen flow rate and ORi (p < 0.001). These methods effectively increased FiO2 and ORi, with over half of the values exceeding 40% and 0.4, respectively. The tight-vented mask showed variable increases in FiO2, ranging between 22 and 90%. Despite method-dependent variations, all devices increased SpO2 > 98% as the FiO2 increased (p = 0.002). In conclusion, nasal prongs and the mask connected to the Venturi valve showed the highest correlation between the oxygen flow rate and the ORi. These results suggest that using these two techniques in conjunction with ORI can help in optimizing oxygen therapy.

Desarrollo y evaluación de mascarillas de oxigenación en 3D diseñadas para caninos en recuperación post quirúrgica

“…La utilización de mascarillas de oxígeno en perros durante el periodo postquirúrgico ha emergido como un componente esencial en la atención veterinaria desempeñando un papel crucial en la optimización de la recuperación de los caninos tras intervenciones quirúrgicas (Wong et al, 2019). En este contexto, la administración de oxígeno mediante mascarillas diseñadas específicamente para caninos ha demostrado ser una estrategia eficaz para mejorar la oxigenación y acelerar el proceso de recuperación en comparación con métodos convencionales (Bellini & De Benedictis, 2023).…”