Comparison of pulse pressure variation and plethysmographic variability index to predict fluid responsiveness in anesthetized cats

• Autor(a) principal: Dalmagro, Tábata Larissa
• Data de Publicação: 2023
• Tipo de documento: Tese
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/242750
• topic: Domestic cats; Gatos; Hidratação; Pressão arterial; Pletismografia; Goal-directed fluid therapy; Fluid responsiveness; Pulse pressure variation; Plethysmographic variability index

Objective To compare the ability/accuracy of pulse pressure variation (PPV) and plethysmographic variability index (PVI) to predict fluid responsiveness (FR) in anesthetized cats. Study design Prospective, experimental study. Animal population Thirty-one healthy cats (2.7–5.0 kg). Methods During isoflurane anesthesia and volume-controlled ventilation [tidal volume (VT): 12 mL kg-1, 30% of inspiratory pause] a femoral artery catheter was used to measure transpulmonary thermodilution stroke volume (SVTPTD) and PPV. A pulse oximeter probe placed on the tongue measured PVI. Variables were recorded before and after a fluid challenge (FC) with 10 mL kg-1 of lactated Ringer´s over 10 minutes. Based on percent changes in SVTPTD induced by the FC, cats were grouped into responders (SVTPTD ≥15%) or nonresponders (SVTPTD <15%) to volume expansion. Results Four animals were excluded from analysis because of unstable hemodynamic conditions. The FC increased SVTPTD by 21.7 (17.5–38.1)% [median (range)] in responders (n = 15) and by 8.8 (-10.6–14.3)% in nonresponders (n = 12). In two cats, the monitor failed to provide PVI values. The area under the receiver operating characteristics curve (95% confidence intervals) was 0.853 (0.664–0.959) for PPV and 0.702 (0.490–0.914) for PVI. PPV values >17% predicted responders to volume expansion with 75% specificity and 86.7% sensitivity (p <0.0001); PVI did not show predictive ability (p = 0.062). The range of PPV values associated with higher probability of false positives (18–23%) was larger and included more animals (11/27 cats) than the range associated with higher probability of false negatives (14–17% and 4/27 cats, respectively). Conclusions and clinical relevance PPV >17% predicted responders to volume expansion with an increased probability of false positive results, suggesting that a VT of 12 mL kg-1 is excessively large for accurate prediction of FR in feline species. PVI showed limited clinical application in cats.