Dataset Information

Perioperative blood loss: estimation of blood volume loss or haemoglobin mass loss?

ABSTRACT:

Background

Perioperative blood loss is an essential parameter in research into Patient Blood Management. However, currently there is no "gold standard" method to quantify it. Direct measurements of blood loss are considered unreliable methods, and the formulae to estimate it have proven to be significantly inaccurate. Given the need for better research tools, this study evaluated an estimation of haemoglobin mass loss as an alternative approach to estimate perioperative blood loss, and compared it to estimations based on blood volume loss.

Material and methods

We studied one hundred consecutive patients undergoing urological laparoscopic surgery. Both haemoglobin mass loss and blood volume loss were directly measured during surgery, under highly controlled conditions for a reliable direct measurement of blood loss. Three formulae were studied: 1) a haemoglobin mass loss formula, which estimated blood loss in terms of haemoglobin mass loss, 2) the López-Picado's formula and 3) an empirical volume formula that estimated blood loss in terms of blood volume loss. The empirical volume formula was developed within the study with the aim of providing the best possible estimation of blood volume loss in the studied population. The formulae were evaluated and compared by assessing their agreements with their respective direct measurements of blood loss.

Results

The haemoglobin mass loss formula met the predefined agreement criterion of ±71 g, with 95% limits of agreement ranging from 0.6 to 44.1 g and a moderate overestimation of 22.4. In comparison to both blood volume loss formulae, the haemoglobin mass loss formula was superior in every agreement parameter evaluated.

Discussion

In this study, the estimation of haemoglobin mass loss was found to be a more accurate method to estimate perioperative blood loss. This estimation method could be a robust research tool, although more studies are needed to establish its reliability.

SUBMITTER: Jaramillo S

PROVIDER: S-EPMC7053522 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Publications

Perioperative blood loss: estimation of blood volume loss or haemoglobin mass loss?

Jaramillo Sebastian S Montane-Muntane Mar M Gambus Pedro L PL Capitan David D Navarro-Ripoll Ricard R Blasi Annabel A

Blood transfusion = Trasfusione del sangue 20191127 1

<h4>Background</h4>Perioperative blood loss is an essential parameter in research into Patient Blood Management. However, currently there is no "gold standard" method to quantify it. Direct measurements of blood loss are considered unreliable methods, and the formulae to estimate it have proven to be significantly inaccurate. Given the need for better research tools, this study evaluated an estimation of haemoglobin mass loss as an alternative approach to estimate perioperative blood loss, and c ...[more]

PMID: 31855150

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Dataset Information

Perioperative blood loss: estimation of blood volume loss or haemoglobin mass loss?

Background

Material and methods

Results

Discussion

Publications

Perioperative blood loss: estimation of blood volume loss or haemoglobin mass loss?

Similar Datasets

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