The Value of Body Surface Area Used in Postpartum Hemorrhage Define Postpartum Hemorrhage

Background: Blood loss as a percentage of total blood volume for redefining PPH may be more appropriate compared to the 500ml cutoff for every pregnant woman. This study is to investigate the value of body surface area in redefining PPH.Methods: In our prospective clinical observational study, we calculated the total blood volume using body surface area and measured blood loss at delivery using gravimetric and volumetric methods for all pregnant women included in our cohort (n=1715). For the five different body surface area groups, we determined different percentages of blood loss in total blood volume among 1201 participants. Furthermore, we compared the prediction values in blood transfusion based on the quantification of bleeding or proportion of blood loss in total blood volume at different quintiles among 514 severe PPH cases. Results: The median total blood volume and body surface area were 4639ml and 1.73 m2, respectively. The median total blood volume increased with increasing body surface area, and the different proportions of total blood volume increased accordingly. The median blood loss was 380ml and represented 8.28% of total blood volume. The median measured 24h blood loss across quintile 1 to 5 was 363ml, 360ml, 390ml, 380ml, 440ml, respectively. Using the definition with blood loss of 500 ml and 13% percentage of total blood volume, the incidence of PPH was 30% and 19%. However, the changes of the circulatory system secondary to obstetric hemorrhage was not significantly different at each quintile. Additionally, use of blood loss or the percentage of blood loss in total blood volume has high specificity and sensitivity as the indicators to predict blood transfusion.Conclusions: Our results suggest that blood loss exceeds 13% of total blood volume as a definition of postpartum hemorrhage. Blood loss above 30% of total blood volume may be recommended for blood transfusion.

Oral saline consumption and pressor responses to acute physical stress

Sodium induced volume loading may alter pressor responses to physical stress, an early symptom of cardiovascular disease. Purpose: Study 1: Determine the time point where total blood volume and serum sodium were elevated following saline consumption. Study 2: Examine the BP response to isometric handgrip (HG) and the cold pressor test (CPT) following saline consumption. Methods: Study 1: Eight participants drank 423 mL of normal saline (sodium 154 mmol/L) and had blood draws every 30 min for 3 h. Study 2: Sixteen participants underwent two randomized data collection visits; a control and experimental visit 90 min following saline consumption. Participants underwent 2 min of isometric HG, post exercise ischemia (PEI), and CPT. Results: Study 1: Total blood volume (3.8 ± 3.0 Δ%) and serum sodium (3.5 ± 3.6 Δ%) were elevated (P < 0.05) by the 90 min time point. Study 2: There were no differences in mean arterial pressure (MAP) during HG (EXP: 17.4 ± 8.2 ΔmmHg; CON: 19.1 ± 6.0 ΔmmHg), PEI (EXP: 16.9 ± 11.7 ΔmmHg; CON: 16.9 ± 7.8 ΔmmHg), or the CPT (EXP: 20.3 ± 10.8 ΔmmHg; CON: 20.9 ± 11.7 ΔmmHg) between conditions (P > 0.05). MAP recovery from the CPT was slower following saline consumption (1 min recovery: EXP; 15.7 ± 7.9 ΔmmHg, CON; 12.3 ± 8.9 ΔmmHg, P < 0.05). Conclusion: Data showed no difference in cardiovascular responses during HG or the CPT between conditions. BP recovery was delayed by saline consumption following the CPT.

Measurement of Circulation of Blood Volume(CBV) and Total Blood Volume(TBV) in Heart using Doppler Color Flow Imaging in Ultrasound Videos

Total blood volume (TBV) analysis is key to manage the patients with cardiopulmonary bypass (CPB) cardiac surgery. Circulation of blood volume (CBV) is essential because the processes that maintain the connection between red cell volume (RCV), plasma volume (PV) and CBV may not be measured. The differences in significant surgery in patients do not always work efficiently and changes in CBV and need intensive care. The visible physiological clinical shock require urgent methods to regulate CBV because the current method is complicated and involves intervention. The current approaches to estimating blood quantity are labor-intensive, complex, and time-consuming. Severe depletion of quantity leads to selective vasoconstriction masking. Last decade, science has introduced different techniques for estimating blood quantity. So the scheme that can offer a precise assessment of blood quantity in the human body needs to be implemented. In this paper, a system is proposed where color flow imaging is used to measure TBV and CBV. The videos used are Doppler 2d echocardiogram which shows the color Doppler flow in the heart. The method used in this paper can be an alternative to the present methods of calculating the TBV and CBV as it is easy to measure the parameters with the help of Doppler velocity.