Global hemostasis in healthy bitches during pregnancy and at different estrous cycle stages: Evaluation of routine hemostatic tests and thromboelastometry

Association of prothrombin time, thrombin time and activated partial thromboplastin time levels with preeclampsia: a systematic review and meta-analysis

BACKGROUND

Preeclampsia (PE), an obstetric disorder, remains one of the leading causes of maternal and infant mortality worldwide. In individuals with PE, the coagulation-fibrinolytic system is believed to be among the most significantly impacted systems due to maternal inflammatory responses and immune dysfunction. Therefore, this systematic review and meta-analysis aimed to assess the association of prothrombin time (PT), thrombin time (TT) and activated partial thromboplastin time (APTT) levels with preeclampsia.

METHODS

This systematic review and meta-analysis was conducted in accordance with the PRISMA guidelines. Articles relevant to the study, published from July 26, 2013, to July 26, 2023, were systematically searched across various databases including PubMed, Scopus, Embase, and Hinari. The methodological quality of the articles was evaluated using the Joanna Briggs Institute critical appraisal checklist. Utilizing Stata version 14.0, a random-effects model was employed to estimate the pooled standardized mean difference (SMD) along with the respective 95% CIs. The I2 statistics and Cochrane Q test were utilized to assess heterogeneity, while subgroup analyses were performed to explore its sources. Furthermore, Egger's regression test and funnel plot were employed to assess publication bias among the included studies.

RESULTS

A total of 30 articles, involving 5,964 individuals (2,883 with PE and 3,081 as normotensive pregnant mothers), were included in this study. The overall pooled SMD for PT, APTT, and TT between PE and normotensive pregnant mothers were 0.97 (95% CI: 0.65-1.29, p < 0.001), 1.05 (95% CI: 0.74-1.36, p < 0.001), and 0.30 (95% CI: -0.08-0.69, p = 0.11), respectively. The pooled SMD indicates a significant increase in PT and APTT levels among PE patients compared to normotensive pregnant mothers, while the increase in TT levels among PE patients was not statistically significant.

CONCLUSIONS

The meta-analysis underscores the association between PE and prolonged PT and APTT. This suggests that evaluating coagulation parameters like PT, APTT, and TT in pregnant women could offer easily accessible and cost-effective clinical indicators for assessing PE. However, multicenter longitudinal studies are needed to evaluate their effectiveness across various gestational weeks of pregnancy.

Luteal phase decrease in packed cell volume in healthy non-pregnant and pregnant bitches

OBJECTIVES

To establish packed cell volume (PCV) ranges for non-pregnant, pregnant and post-partum bitches from day 10 of proestrus, investigating any relationship with parity and litter size.

METHODS

This prospective cohort study used 37 healthy breeding bitches to examine PCV counts from routine blood samples collected every 4 weeks, from day 10 of proestrus, as part of routine PCV monitoring.

RESULTS

For pregnant (n = 19) and non-pregnant (n = 18) bitches, PCV decreased until week 8 (corresponding to 8.5 ± 1.1 days before whelping for pregnant bitches) and recovered by 16-20 weeks after the initial sample; bitches that whelped average and large litters showed greater declines. PCV began to recover sooner for bitches that had previously whelped one or two litters compared to bitches that had previously whelped three or more litters. There was a significant three-way interaction between time after the onset of proestrus, litter size and the number of previous litters which demonstrated that the large decrease in PCV for bitches that had previously whelped three or more litters only occurred in bitches that were expecting an average or large sized litter.

CLINICAL SIGNIFICANCE

Chronological variation in PCV for pregnant and non-pregnant bitches was established during the reproductive cycle. There was no evidence to suggest that routine PCV measurement for normal, healthy bitches would be beneficial. However, knowledge from this study may be useful when deciding whether to prospectively monitor a bitch where there is a history of previous pregnancy-related anaemia, when performing a caesarean section due to the anticipated blood loss during surgery, or when examining blood profiles for post-litter bitches.

Ultrasonographic changes in fetal gastrointestinal motility during the last ten days before parturition in dogs

Fetal gastrointestinal motility (FGM) was suggested as useful to assess fetal maturity. Our study aimed to quantify FGM in relation to days before parturition (DBP), maternal size, and sex ratio of pups. During the last ten days of pregnancy, 23 clinically healthy pregnant bitches of 16 different breeds ranging in age from 2 to 9 years and body weight from 3.5 to 56.8 kg were monitored twice. The fetal intestine was observed in longitudinal and transversal scan on 3 of the most caudal fetuses in both uterine horns. Gestational age was counted backward from parturition day. The number of fetuses showing FGM was recorded in time in I (-11/-5 DBP) and II (-4/0 DBP). A Mann-Whitney test was performed to analyze variations of FGM% in relation to time and parity. A Kruskal-Wallis test was performed to identify variations of FGM% in relation to maternal size and sex ratio. Statistical significance was set at α = 0.05. A total of 147 FGM observations on 50 ultrasonographic monitoring points were performed. The FGM% was higher during time II compared to time I (median: 33%, range 0-100% vs. 100%, range 33-100%; P < 0.0001). FGM% was higher in small compared to large size bitches (median: 100%, range 67-100% vs. 67%, range 0-100%; P = 0.01). FGM% was not affected by parity and sex ratio. As previously reported, a significant increase in FGM% was observed in the last five DBP. FGM observation may be influenced by the maternal size, with easier evaluation in small size bitches, as well as ultrasound equipment and positioning.

A case report of a rapid development of fetal anasarca in a canine pregnancy at term

A 5-year-old healthy pluriparous pregnant Flat-coated Retriever bitch was monitored by ultrasound on post-ovulation days 30 and 57: no deviation from normality picture were observed. On day 60, one of the three most caudal fetuses showed ultrasonographic signs of fetal anasarca: subcutaneous edema and anechoic fluid in thoracic and abdominal cavities. There was an increased volume of extra-fetal fluids. On day 64 a Cesarean section was performed and one of the seven pups that were delivered, a female, showed generalized subcutaneous edema and died soon after birth. She weighed 660 g, compared to a mean of 472 g for the other 6 normal fetuses. A total of 295, 40 and 27.5 mL of liquid were collected from subcutaneous tissue, abdominal and thoracic cavity, respectively. Liver showed sub-glissonian necrotic areas. Molecular analyses with PCR method for canine Herpesvirus, Parvovirus, Adenovirus, Leptospira interrogans, Chlamydia spp., Neospora caninum and Toxoplasma gondii from pools of organs (spleen, kidney and brain) and pleural effusion tested negative. This is the first reported case of fetal anasarca with a rapid onset diagnosed on day 60 post-ovulation just three days after observing a normal ultrasonographic pattern in Flat-coated Retriever. Ultrasonographic diagnosis of fetal anasarca is of primary importance when assisting parturition, due to its inherent risk of dystocia. Ultrasonographic monitoring in the immediate prepartum period may be useful in all breeds as it may help to detect ultrasonographic alterations occurring right before term such as anasarca.

Comparison of viscoelastic test results from blood collected near simultaneously from the jugular and saphenous veins in cats

OBJECTIVES

The aim of this study was to compare viscoelastic test results from samples collected from a jugular vein using a 20 G needle and a medial saphenous vein using a 22 G needle in cats presenting for elective ovariohysterectomy (OHE) or castration.

METHODS

Forty apparently healthy cats (20 males and 20 females) presenting for elective OHE or castration were included in a prospective study observing viscoelastic test results from central and peripherally collected whole blood. Cats were anesthetized during blood collection with a standardized protocol including buprenorphine, ketamine, dexmedetomidine and isoflurane. Blood samples from jugular and saphenous veins were collected near simultaneously. Viscoelastic evaluations of whole blood were performed using a point-of-care device measuring clot time (CT), clot formation time (CFT), alpha angle (α), maximum clot formation (MCF), and amplitude at 10 and 20 mins (A10 and A20, respectively). Viscoelastometry continued post-clot time to determine a lysis index at 30 and 45 mins (LI30 and LI45, respectively) to assess fibrinolysis.

RESULTS

Studied cats had a median age of 18 months (range 5 months to 5 years) and a median weight of 3.6 kg (range 2.7-5.9 kg). A total of 80 samples were available for analysis. While lysis indices were not different, viscoelastic measures of coagulation differed between sampling sites (CT, P <0.005; CFT, P = 0.01; α, P <0.05; MCF, P <0.0005; A10, P <0.0005; A20, P <0.0005).

CONCLUSIONS AND RELEVANCE

Viscoelastic results from jugular venous blood samples appear to be more hypercoagulable than those collected from the medial saphenous vein, suggesting that the same site should be used consistently for serial monitoring or for collecting study data.

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

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.

Survival and fertility of bitches undergoing caesarean section

BACKGROUND

With the increasing popularity of planned caesarean section, the need for knowledge regarding this surgery has become increasingly important. The reported death and survival rates for caesarean sections vary widely. Another important aspect is the fertility rate in subsequent oestrous after caesarean section. The aim of this study was to investigate the mortality and survival rate of bitches during caesarean section. Additionally, the fertility of bitches after caesarean sections was determined.

METHODS

Caesarean sections which were performed in the years 1997-2009 at two university clinics were evaluated retrospectively. A distinction was made between bitches in which a conservative caesarean section was performed and bitches with a caesarean section followed by an ovariohysterectomy.

RESULTS

A total of 482 caesarean sections were included in the study. The overall mortality rate was 3.11 per cent, with 2.59 per cent during or after a conservative caesarean section and 4.19 per cent during or after caesarean section with ovariohysterectomy. The reason for ovariohysterectomy was the owner's preference in 63 bitches (47.01 per cent); in 71 (52.98 per cent) bitches, ovariohysterectomy was performed due to a medical indication. The fertility rate after caesarean section was 100 per cent.

CONCLUSION

The results show a high mortality rate during and after caesarean section. On the other hand, caesarean section does not seem to have a big impact on further fertility. Further studies are needed to investigate possible reduction of litter sizes and the suitability of caesarean section in subsequent pregnancies.

Time course of serum cobalamin, folate, and total iron binding capacity concentrations in pregnant bitches and association with hematological variables and survival

Background

Hypocobalaminemia, hypofolatemia and iron deficiency are associated with pregnancy‐related anemia (PRA) and neonatal survival (NS) in women. Similar associations have not been investigated in pregnant bitches.

Objectives

To investigate time course and associations of serum cobalamin, folate and iron status indicators with hematological variables and NS in pregnant bitches.

Animals

Forty‐eight pregnant bitches.

Methods

A prospective cohort study. Pregnancy was confirmed by abdominal ultrasonography twice during mid‐ and late pregnancy, concurrently with blood sampling. Associations among pregnancy stage, NS and laboratory variables were assessed by generalized estimating equations.

Results

Compared with midpregnancy, serum cobalamin (adjusted mean [95% confidence interval, CI]) decreased at late pregnancy (430 pg/mL [394‐466] versus 330 pg/mL [303‐357], respectively; P < .001), whereas serum folate did not. Every increment of 1 in parity number or litter size corresponded to 28.6 pg/mL (95% CI, 5.6‐51.6; P = .02) and 20.3 pg/mL (95% CI, 10.9‐29.7; P < .001) decrease in serum cobalamin concentration. Compared with midpregnancy, serum iron (P < .001) and transferrin saturation (P = .01) increased at late pregnancy. The decrease in red blood cell count (P < .001) at late pregnancy was significantly, albeit weakly, correlated with decreasing serum folate concentration (r = 0.33; P = .02). None of the measures was associated with NS.

Conclusions and Clinical Significance

Pregnancy‐related anemia was common at late pregnancy. Unlike in women, in pregnant bitches, serum iron and transferrin saturation were increased at late pregnancy. Future studies are warranted to investigate the clinical ramifications of hypocobalaminemia in pregnant bitches and the utility of prophylactic folate administration in mitigating PRA.