Do we visually estimate intra-operative blood loss better with white or green sponges and is the deviation from the real blood loss clinically acceptable? Results from a simulated scenario study

Abstract

Background The intraoperative blood loss is estimated daily in the operating room and is mainly done by visual techniques. Due to local standards, the surgical sponge colours can vary (e.g. white in US, green in Germany). The influence of sponge colour on accuracy of estimation has not been in the focus of research yet. Material and methods A blood loss simulation study containing four “bleeding” scenarios each per sponge colour were created by using expired whole blood donation samples. The blood donations were applied to white and green surgical sponges after dilution with full electrolyte solution. Study participants had to estimate the absorbed blood loss in sponges in all scenarios. The difference to the reference blood loss was analysed. Multivariate linear regression analysis was performed to investigate other influence factors such as staff experience and sponge colour. Results A total of 53 anaesthesists participated in the study. Visual estimation correlated moderately with reference blood loss in white (Spearman's rho: 0.521; p = 3.748*10 −16 ) and green sponges (Spearman's rho: 0.452; p = 4.683*10 −12 ). The median visually estimated blood loss was higher in white sponges (250ml IRQ 150–412.5ml) than in green sponges (150ml IQR 100-300ml), compared to reference blood loss (103ml IQR 86–162.8). For both colour types of sponges, major under- and overestimation was observed. The multivariate statistics demonstrates that fabric colours have a significant influence on estimation (p = 3.04*10 −10 ), as well as clinician’s qualification level (p = 2.20*10 −10 , p = 1.54*10 −08 ) and amount of RBL to be estimated (p < 2*10 −16 ). Conclusion The deviation of correct blood loss estimation was smaller with white surgical sponges compared to green sponges. In general, deviations were so severe for both types of sponges, that it appears to be advisable to refrain from visually estimating blood loss whenever possible and instead to use other techniques such as e.g. colorimetric estimation.

The Usage of Intravenous Tranexamic Acid in Reduction Mammaplasty Safely Reduces Hematoma Rates

“…One interesting finding of our study was that there was no significant difference in estimated blood loss between the 2 cohorts (TXA vs no TXA). Although this finding was unexpected given the known reduction in blood loss after TXA administration, studies have shown that accurately estimating blood loss is a difficult task and depends on various factors, including color and types of sponges used intraoperatively 35–37 . Furthermore, there was no significant difference in operative time between the 2 cohorts.…”

“…Although this finding was unexpected given the known reduction in blood loss after TXA administration, studies have shown that accurately estimating blood loss is a difficult task and depends on various factors, including color and types of sponges used intraoperatively. [35][36][37] Furthermore, there was no significant difference in operative time between the 2 cohorts. Our group anticipated that operative time may be decreased with the use of TXA and its role in reducing time to hemostasis; however, that was not the case.…”

Catastrophic and Critical Intraoperative Events during Pediatric Craniofacial Surgery

“… 13 Visual estimation of blood loss is particularly inaccurate. 14 Having an experienced anesthesia team is an essential component to successful fluid and volume management. The triggers for transfusion of blood products include a hemoglobin less than 7/0 g/dL, abnormal coagulation parameters, obvious ongoing blood loss and abnormal vital signs but often the decision to transfuse may be subjective and influenced by experience.…”

Quantification of blood loss in obstetric haemorrhage: implications on intervention and transfusion

“…There is no difference in the error of estimation between different types of healthcare professionals or level of experience; however, the fabric colour of swabs can have a significant influence on blood loss estimation: white swabs show a smaller value of deviation than green swabs. 19,20 Simulation training and the use of pictograms has been shown to improve visual estimation of blood loss, but this is not retained over time. 19,21 Direct or volumetric quantification of blood loss involves collecting and measuring blood loss in drapes and containers.…”

“…Larger volume losses can be underestimated, increasing the risk of morbidity and mortality associated with significant PPH. There is no difference in the error of estimation between different types of healthcare professionals or level of experience; however, the fabric colour of swabs can have a significant influence on blood loss estimation: white swabs show a smaller value of deviation than green swabs 19,20 . Simulation training and the use of pictograms has been shown to improve visual estimation of blood loss, but this is not retained over time 19,21 …”