Can the Non-pneumatic Anti-Shock Garment (NASG) reduce adverse maternal outcomes from postpartum hemorrhage? Evidence from Egypt and Nigeria

Background. Postpartum hemorrhage (PPH) is the leading cause of maternal mortality and severe maternal morbidity. The Non-pneumatic Anti-Shock Garment (NASG), a first-aid lower-body compression device, may decrease adverse outcomes from obstetric hemorrhage. This article is the first to report the effect of the NASG for PPH. Methods. This pre-intervention/NASG study of 854 women was conducted in four referral facilities in Nigeria and two in Egypt between 2004-2008. Entry criteria were women with PPH due to uterine atony, retained placenta, ruptured uterus, vaginal or cervical lacerations or placenta accreta with estimated blood loss of 750 mL and one clinical sign of shock. Differences in demographics, conditions on study entry, treatment and outcomes were examined. The Wilcoxon rank-sum test and relative risks with 95% confidence intervals were calculated for primary outcomes – measured blood loss, emergency hysterectomy, mortality, morbidity (each individually), and a combined variable, “adverse outcomes”, defined as severe morbidity and mortality. A multiple logistic regression model was fitted to test the independent association between the NASG and the combined severe morbidity and mortality outcome. Results. Measured blood loss decreased by 50% between phases; women experienced 400 mL of median blood loss after study entry in the pre-intervention and 200 mL in the NASG phase (p < 0.0001). As individual outcomes, mortality decreased from 9% pre-intervention to 3.1% in the NASG phase (RR 0.35, 95% CI 0.19-0.62); severe morbidity decreased from 4.2% to 1%, in the NASG phase (RR 0.24, 95% CI 0.09-0.67). As a combination, "adverse outcomes," decreased from 12.8% to 4.1% in the NASG phase (RR 0.32, 95% CI 0.19-0.53). In a multiple logistic regression model, the NASG was associated with the combined outcome of severe maternal morbidity and mortality (OR 0.42, 95% CI 0.18-0.99). Conclusion. In this non-randomized study, in which bias is inherent, the NASG showed promise for reducing blood loss, emergency hysterectomy, morbidity and mortality associated with PPH in referral facilities in Egypt and Nigeria. © 2010 Mourad-Youssif et al; licensee BioMed Central Ltd. This study is a sub-analysis of data collected between 2004 and 2008. The methods have been described in more detail in previously published studies of obstetric hemorrhage from all etiologies [11,12]. Briefly, this is a pre-intervention/intervention study, data were collected during the pre-intervention phase, when clinicians used a standardized obstetric hemorrhage protocol, for women with hypovolemic shock secondary to obstetric hemorrhage and outcomes of interest were recorded. Next, the NASG was introduced. During the NASG intervention phase, clinicians used the same protocol plus the NASG for women with hypovolemic shock secondary to obstetric hemorrhage. The pre-intervention and intervention phases were exactly the same length in the Egypt study, length of pre-intervention and intervention phases in Nigeria differed, but in each of the four facilities pre-intervention phases were shorter than intervention phases. For the present PPH sub-set analysis, we examined only the data on women admitted for PPH (n = 854) at tertiary care facilities with roughly equivalent pre-intervention (n = 343) and NASG phases (n = 511). PPH diagnoses included uterine atony, retained placenta or tissue, ruptured uterus, vaginal/cervical lacerations and placenta accreta. To be eligible for the study, women presented with PPH and shock, defined by an initial blood loss of ≥ 750 mL and at least one clinical sign of shock (systolic blood pressure < 100 mmHg or pulse > 100 beats per minute). The University of California, San Francisco (UCSF) Committee on Human Research (approval number H6899-23524), the National Reproductive Health Research Committee of the Nigeria Federal Ministry of Health, and the Ethics Committees of the El Galaa Maternity Teaching Hospital and Assiut University Women’s Health Center gave ethical approval for the study. After an explanation of study aims, risks and benefits, all pre-intervention study participants gave verbal consent, and all NASG participants gave written consent to the use of the NASG. A United States Federal waiver of consent/authorization for minimal-risk research (45 CFR 46, 45 CFR 164.512) was obtained so that women who were unconscious or confused at the time of study entry were enrolled in the study without consent or with a relative’s consent. Once the woman had regained consciousness and attained a normal sensorium, she was consented and gave written permission, even if a relative had given consent on her behalf while she was unconscious. The evidence-based protocol for the treatment of PPH and shock included administration of crystalloid intravenous fluids (≥ 1500 mL in the first hour), uterotonic medications (oxytocin, ergometrine, syntometrine, misoprostol), uterine massage for patients with uterine atony, vaginal procedures (repair of lacerations, curettage for retained tissue, bimanual compression and/or manual removal of placenta) and when necessary, abdominal surgeries (arterial ligation, B lynch compression sutures, hysterectomy). After entry to the study, all study participants in both phases had blood loss measured with a calibrated blood collection and measurement drape (BRASS-V Fixable Drape™, Madurai, India), which was placed under them for accurate measurement of blood loss during resuscitation and hemorrhage treatment. This drape has been compared as equivalent to spectrophotometry for accuracy [13]. For women in the intervention phase of the study, the NASG was applied at the time of study admission and remained in place for the duration of the study. The NASG was applied sequentially, starting at the ankles with two segment #1 panels, one for each ankle, then to the calves (segments #2), thighs (segments #3), then segment #4 to the pelvis, and finally closing the double segment (#5 and #6), with the pressure ball, around the abdomen. All patients were monitored every 15 minutes for vital signs, level of consciousness, uterine condition, bleeding, and urine output, until they were stable. If surgery were required for NASG patients, the abdominal section was opened immediately before the skin incision and closed after the abdominal bandage was applied. Study discharge and NASG removal time were determined by two hours of hemodynamic stability (systolic blood pressure > 100 mmHg and pulse < 100 beats per minute) and vaginal bleeding of < 50 mL/hour. The device was then removed in the same order as it was applied, starting at the ankles with 15 minute intervals between each segment. Clinician/data collectors were trained in the standard management of PPH and shock, collection and measurement of blood loss and completion of data collection forms. In Nigeria, paper data forms were reviewed by data supervisors and the Nigerian Principal Investigators, copied, and sent to UCSF where data were entered into a Microsoft Access database (Microsoft, Redmond, WA, USA) and checked for errors and inconsistencies. In Egypt, paper forms were reviewed by the Egyptian Principal Investigators and electronically transmitted by data fax (Clinical DataFax Systems Inc., Ontario, Canada) to UCSF. A woman's condition on study entry was calculated using mean arterial pressure (MAP = [2*Diastolic Blood Pressure] + Systolic Blood Pressure/3) [14]. Primary outcomes included cumulative blood loss measured in the drape, emergency hysterectomy, and "adverse outcomes," which was a combined variable of severe maternal morbidity and mortality. Severe maternal morbidity included end-organ dysfunctions related to hemorrhage including cardiac, pulmonary, renal, and CNS [15]. Tests of significance of differences by study phase were chi-squares for categorical variables, t-tests (assuming unequal variances) for normally-distributed continuous variables and Wilcoxon rank-sum tests for non-normally distributed continuous variables. Normality was tested using qnorm and sktest in STATA. To estimate the independent effect of the NASG, we used a multiple logistic regression model to control for other characteristics which might predict adverse outcomes. The independent variables included in the model were selected on the basis of their prior significance in the literature on maternal mortality and for significant association (at the 95% confidence level) with mortality and morbidity in bivariate analyses of this data. Variables included in the final model were high parity, MAP < 60, where the patient began bleeding (outside the facility and transferred in vs. began bleeding in the facility), and study phase (pre-intervention or NASG). All data were analyzed using STATA version 10 (StataCorp, College Station, TX, USA).