Browsing by Author "Boysen SR"

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    Establishment of reference intervals for ultrasonographically derived caudal vena cava parameters from 110 healthy, lightly sedated cats
    (SAGE Publications for the International Society of Feline Medicine and American Association of Feline Practitioners, 2023-10-24) Hultman TM; Rosanowski SM; Jalava SM; Boysen SR; Yozova ID
    Objectives: The present study aimed to establish reference intervals (RIs) for ultrasonographically derived caudal vena cava (CVC) parameters in healthy cats. Methods: A prospective, observational, experimental single-centre study involving 110 cats was conducted. Two trained operators scanned all cats in a randomised order. Two sets of cine loops per cat were conducted by each operator from the subxiphoid view with cats in lateral recumbency. Two blinded raters measured the narrowest inspiratory (CVCinsp) and widest expiratory (CVCexp) diameter over two separate respiratory cycles for each operator (four measurements in total for each rater) at the point the CVC crosses the diaphragm. The CVC collapsibility index (CVCCI) was calculated. Reference intervals and limits were calculated for CVC parameters with outliers removed to include the central 95% of CVC values and the non-parametric 90% confidence intervals (90% CIs). The CVCCI interval included the central 95th (2.5th and 97.5th) centiles bounded by the 90% CI. Intra- and inter-rater and intra- and inter-operator reliabilities were calculated for each parameter using a two-way random-effects model. A Bland–Altman plot was used to visualise the CVCCI between the two raters. Results: In total, 880 measurements were included for each diameter and 440 CVCCI values were calculated. The CVC diameters were normally distributed, whereas the CVCCI was not. The calculated RIs were 1.4–6.1 mm for CVCinsp and 2.2–6.7 mm for CVCexp. The median (range) CVCCI was 23% (11–36%) with 2.5th and 97.5th centiles of 2% and 67%, respectively. There was a moderate to good intra-rater and intra-operator reliability for CVC diameter. The intra-rater reliability for the CVCCI was moderate. The inter-rater and inter-operator reliabilities for the CVCCI were poor. Conclusions and relevance: The CVC RIs determined from the subxiphoid site in cats appear to be wider than those reported in dogs, and rater and operator variability is present. Whether precise measurements of CVC parameters are suitable to guide clinical decisions remains to be determined.
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    Ultrasonographically derived caudal vena cava parameters acquired in a standing position and lateral recumbency in healthy, lightly sedated cats: a pilot study.
    (2022-10) Hultman TM; Boysen SR; Owen R; Yozova ID
    OBJECTIVES: The aim of this study was to determine the feasibility of ultrasonographically measuring the caudal vena cava (CVC) at the subxiphoid view of healthy, lightly sedated cats in a standing position and lateral recumbency. METHODS: This was a prospective, observational, experimental single-centre study. Twenty healthy research-purposed cats were enrolled. Two trained operators scanned each cat in two positions - standing and lateral recumbency - in a randomised order. CVC diameter was measured at the narrowest diameter during inspiration and at the widest diameter during expiration, at two anatomical locations along the CVC - where the CVC crosses the diaphragm (base) and 2 mm caudal to the diaphragm. The CVC collapsibility index (CVC-CI) was calculated for each site. Normalcy was assessed with a Shapiro-Wilk test. A one-way ANOVA with post-hoc Tukey's test was used to compare inspiratory with expiratory values within and between groups. A paired t-test compared the CVC-CI between groups (P ⩽0.05 indicated statistical significance). Spearman's correlation and Bland-Altman analysis assessed inter-operator variability. RESULTS: All ultrasonographic data passed normalcy and were reported as mean ± SD. When compared with each other, inspiratory and expiratory values were statistically different for position, location and operator (all P <0.0001). There was no statistically significant difference between lateral recumbency or standing position for inspiratory, expiratory and CVC-CI values. Inter-operator variability was substantial, with operator 2 consistently obtaining smaller measurements than operator 1. The mean CVC-CI in lateral recumbency at the base was 24% for operator 1 and 37% for operator 2. For the same site in standing position, CVC-CI was 27% and 41% for operators 1 and 2, respectively. CONCLUSIONS AND RELEVANCE: This pilot study demonstrates that it is possible to ultrasonographically measure the CVC diameter in both lateral recumbency and a standing position in healthy, lightly sedated cats. However, measurements obtained are operator dependent with variability between individuals. Further studies are needed to determine if ultrasonographic CVC assessment will prove helpful in estimating intravascular volume status in cats.