Blood loss and coagulation profile in pregnant and non-pregnant queens undergoing elective ovariohysterectomy

Abstract

Objectives The aims of this study were to determine if there is increased risk of intraoperative bleeding in pregnant cats undergoing elective ovariohysterectomy (OHE), and to compare coagulation in queens in various stages of estrus and pregnancy subjected to elective OHE using a whole-blood viscoelastic assay. Methods Intraoperative blood loss was compared between non-pregnant and pregnant cats undergoing elective OHE. Viscoelastic evaluations of whole blood drawn pre- and postoperatively were performed using a point-of-care device measuring clot time (CT), clot formation time (CFT), alpha angle, maximum clot formation (MCF), amplitude at 10 and 20 mins (A10 and A20, respectively), and lysis index at 30 and 45 mins after MCF (LI30 and LI45, respectively). Results One hundred and ninety-three cats underwent OHE by a ventral midline approach. Median blood loss was greater for pregnant cats (2.0 ml, range <0.5–13 ml) than non-pregnant cats (<0.5 ml, range <0.5–15 ml; P <0.0001). Preoperatively, pregnant cats had a shorter median CFT (165 s vs 190.5 s), increased median A10 (31 from 25.5 VCM units) and A20 (38 from 35 VCM units), and a lower median LI45 (99% from 100%) than non-pregnant cats. Postoperatively, A10 and A20 increased, and LI30 and LI45 decreased in both non-pregnant and pregnant queens. In pregnant queens, mean CT also increased postoperatively. Conclusions and relevance Pregnant cats were relatively hypercoagulable and had an increased rate of clot lysis than non-pregnant cats. Intraoperative blood loss was increased in pregnant vs non-pregnant cats, but no clinically relevant bleeding conditions occurred.

Estimation of the intraoperative blood loss in dogs undergoing enucleation

“…The gravimetric method is employed in obstetrics 8,9 and procedures including pediatric orthopaedics 36 adenotonsillectomy 37,38 and cleft palate repair 39 . In veterinary literature, the gravimetric method has demonstrated good correlation with spectrophotometric estimation of hemoglobin content in dogs undergoing three different types of surgery (cutaneous tumor excision, orthopedic procedure, laparotomy) 40 and found comparable to the HemoCue™ photometer device when applied to both the suction fluids and surgical swabs from dogs undergoing spinal surgery 41 and has also recently been used in a study to estimate blood loss during feline ovariohysterectomy 42 . The gravimetric method has been found to underestimate blood loss 43–45 due to factors including evaporative loss 40 and the inability to measure blood adherent to surgical instruments and gloves 39 .…”

Viscoelastic Coagulation Monitor (VCM^Vet) Reference Intervals and Sex Differences in Mature Adult Mice

“…To our knowledge, this study is the first to demonstrate use of VCM Vet TM to analyze blood coagulation properties in mice. To date, other investigators have published studies using VCM Vet TM to analyze blood from cats [7, 8], dogs [14], and bats [10]. In this study, we determined VCM Vet TM RIs for healthy mature adult C57BL/6N mice and reference value ranges needed for blood coagulation testing in experimental and preclinical studies with mice.…”

“…The Viscoelastic Coagulation Monitor (VCM Vet TM ; Entegrion Corp.) is a relatively new coagulometer designed specifically for veterinary clinical use that is shown to yield values similar to TEG or ROTEM [1, 7, 8]. The VCM Vet TM instrument is much smaller than other devices, as well as cordless and portable, which is convenient for quickly analyzing fresh whole blood immediately after sampling.…”