A longitudinal study to compare the amount of blood loss in caesarean section using QBL ( Quantitative Blood Loss ) v/s Modified Gross Formula

Globally, delivery by caesarean section ranks among the most common obstetric surgical procedures. Obstetric haemorrhage contributes significantly to maternal mortality and morbidity. An essential component of lowering morbidity during C- section is prevention and early recognition of blood loss through an effective means of measurement. The conventional methods of blood loss estimation often results in undiagnosed PPH. Despite, widespread use of haemoglobin and haematoicrit measurements, even in resource limiting settings, their application in estimating blood loss in obstetric care remains underutilize  In order to realize obstetric haemorrhage at an early stage, it is crucial that ongoing blood  loss should be accurately assessed. However, researchers have reported that obstetricians may underestimate blood loss and these underestimations may result in errors in making decisions about giving the patient blood or blood products.The underestimation of blood loss may result in inadequate fluid resuscitation, hypovolemia, shock, organ damage and impaired tissue oxygenation .Several studies conducted have shown a significant correlation between QBL and Modified gross formula in estimation of blood loss in vaginal deliveries. However, not sufficient evidence has been noted for the same in caesarean section, where the amount of blood loss estimated is often considered as a matter of debate due to traditional methods used for assessing the blood loss which lack accuracy.

Data collection procedure

 After approval from the Ethics Committee,patients will be screened for eligibility considering the inclusion and exclusion criteria and those patients who fit according to inclusion criteria will be recruited in the study.

 Complete history will be collected from the medical record files including patient’s obstetric history at the time of admission and patients will be followed up to the date of discharge.

 Pre- and post operative haemoglobin and haematocrit will be recorded

Pre-operative haematocrit being most recent within 1 week of C- section

Post – operative haematocrit will be measured 48 hours after section.

 Blood loss will be calculated using 2 methods –

 1. Conventional methods – This will include the following -

 - Gravimetric method- a Brasss V drape will be placed under buttocks of patient before starting the caesarean section and the amount of blood collected in the drape at the end of C- section will be recorded

 - Suction canister – the process of quantification of blood loss will begin after the amniotic membrane is ruptured and baby is born. First suctioning of all the amniotic fluid will be done in one suction canister till the delivery of placenta.

After delivery of placenta blood will be suctioned in a different suction canister

• Soaked pads and gauze – weight of dry gauze and pads will be recorded. After section the weight of soaked pads and gauzes will be recorded where 1 gm weight will be taken as 1 ml of blood loss and the difference between the two weights would give an estimate of amount of blood loss

All these will be added to get the amount of blood loss by conventional method

2.     Modified gross formula –

 - Haemoglobin and haematocrit values will be recorded prior to section and then repeated again after 48 hours of surgery

• Amount of blood loss will be calculated using this formula –

• Blood loss - Estimated BV X ( Hct pre-op – Hct post-op ) / Hct average

 Where estimated blood volume will be taken as 70ml/kg

 Blood loss estimation by both the methods will be compared