Transfusion rate and prevalence of unexpected red blood cell alloantibodies in women undergoing hysterectomy for benign disease

A model to predict risk of blood transfusion after gynecologic surgery

BACKGROUND

A model that predicts a patient's risk of receiving a blood transfusion may facilitate selective preoperative testing and more efficient perioperative blood management utilization.

OBJECTIVE

We sought to construct and validate a model that predicts a patient's risk of receiving a blood transfusion after gynecologic surgery.

STUDY DESIGN

In all, 18,319 women who underwent gynecologic surgery at 10 institutions in a single health system by 116 surgeons from January 2010 through June 2014 were analyzed. The data set was split into a model training cohort of 12,219 surgeries performed from January 2010 through December 2012 and a separate validation cohort of 6100 surgeries performed from January 2013 through June 2014. In all, 47 candidate risk factors for transfusion were collected. Multiple logistic models were fit onto the training cohort to predict transfusion within 30 days of surgery. Variables were removed using stepwise backward reduction to find the best parsimonious model. Model discrimination was measured using the concordance index. The model was internally validated using 1000 bootstrapped samples and temporally validated by testing the model's performance in the validation cohort. Calibration and decision curves were plotted to inform clinicians about the accuracy of predicted probabilities and whether the model adds clinical benefit when making decisions.

RESULTS

The transfusion rate in the training cohort was 2% (95% confidence interval, 1.72-2.22). The model had excellent discrimination and calibration during internal validation (bias-corrected concordance index, 0.906; 95% confidence interval, 0.890-0.928) and maintained accuracy during temporal validation using the separate validation cohort (concordance index, 0.915; 95% confidence interval, 0.872-0.954). Calibration curves demonstrated the model was accurate up to 40% then it began to overpredict risk. The model provides superior net benefit when clinical decision thresholds are between 0-50% predicted risk.

CONCLUSION

This model accurately predicts a patient's risk of transfusion after gynecologic surgery facilitating selective preoperative testing and more efficient perioperative blood management utilization.

The Danish Hysterectomy and Hysteroscopy Database

Aim of the database

The steering committee of the Danish Hysterectomy and Hysteroscopy Database (DHHD) has defined the objective of the database: the aim is firstly to reduce complications, readmissions, reoperations; secondly to specify the need for hospitalization after hysterectomy; thirdly to secure quality assessment of hysterectomy and hysteroscopy by setting standards and national guidelines; and finally to intensify the monitoring of laparoscopic surgery and explore long-term side effects after hysterectomy.

Study population

We include all women in Denmark who have had elective benign uterine surgery since 2003. The surgery includes hysterectomy and operative hysteroscopy. In the latter, we include resection of the endometrium and submucosal leiomyomas and ablations of the endometrium.

Main variables

Detailed information about the hysterectomy and hysteroscopy operation techniques, cooperations, and indications is registered directly in the National Patient Register (NPR), as well as relevant lifestyle factors and confounders. It is mandatory to register information about complications and readmissions in the NPR. Data included in DHHD are directly extracted from the NPR.

Descriptive data

Annually approximately 4,300 hysterectomies and 3,200 operative hysteroscopies are performed in Denmark. Since the establishment of the database in 2003, 50,000 hysterectomies have been registered. DHHD’s nationwide cooperation and research have led to national guidelines and regimes. Annual national meetings and nationwide workshops have been organized.

Conclusion

The use of vaginal and laparoscopic hysterectomy methods has increased during the past decade and the overall complication rate and hospital stay have declined. The regional variation in operation methods has also decreased.

Anti-hemorrhagic effect of prophylactic tranexamic acid in benign hysterectomy-a double-blinded randomized placebo-controlled trial

BACKGROUND

Hysterectomy is one of the most frequently performed major gynecological surgical procedures. Even when the indication for the procedure is benign, relatively high complication rates have been reported. Perioperative bleeding seems to represent the most common cause of complications and in 2004, 8% of all women in Denmark undergoing benign hysterectomy experienced a bleeding complication. Tranexamic acid is an antifibrinolytic agent that has shown to effectively reduce bleeding complications within other surgical and medical areas. However, knowledge about the drug's effect in relation to benign hysterectomy is still missing.

OBJECTIVE

To investigate the antihemorrhagic effect of prophylactic tranexamic acid in elective benign hysterectomy.

STUDY DESIGN

A double-blinded randomized placebo-controlled trial was conducted at 4 gynecological departments in Denmark from April 2013 to October 2014. A total of 332 women undergoing benign abdominal, laparoscopic, or vaginal hysterectomy were included in the trial, randomized to either 1 g of intravenous tranexamic acid or placebo at start of surgery. Chi-square test and Student t test statistical analyses were applied.

RESULTS

The primary outcome of intraoperative total blood loss was reduced in the group treated with tranexamic acid compared to the placebo group when estimated both subjectively by the surgeon and objectively by weight (98.4 mL vs 134.8 mL, P = .006 and 100.0 mL vs 166.0 mL, P = .004). The incidence of blood loss ≥500 mL was also significantly reduced (6 vs 21, P = .003), as well as the use of open-label tranexamic acid (7 vs 18, P = .024). Furthermore, the risk of reoperations owing to postoperative hemorrhage was significantly reduced in the tranexamic acid group compared to the placebo group (2 vs 9, P = .034). This corresponds to an absolute risk reduction of 4.2% and number needed to treat of 24. No incidence of thromboembolic events or death was observed in any of the groups.

CONCLUSION

The results support the hypothesis that prophylactic treatment with tranexamic acid reduces the overall total blood loss, the incidence of substantial blood loss, and the need for reoperations owing to postoperative hemorrhage in relation to benign hysterectomy. No incidences of serious adverse events occurred. Thus, tranexamic acid should be considered as a prophylactic treatment prior to elective benign hysterectomy.