PPH Butterfly: a novel device to treat postpartum haemorrhage through uterine compression

Abstract

Objective: Postpartum haemorrhage (PPH) is a significant cause of maternal morbidity and mortality. The most common cause is an inability of the uterus to contract adequately after childbirth. In bimanual compression (BMC), one hand is placed within the vagina and the other hand is on the abdominal wall to compress the uterus. It is effective, but very uncomfortable for the woman. We designed a device that could replicate BMC without inserting a hand vaginally, therefore being less invasive. It could also help in diagnosing the source of the bleeding.

Design: Mixed methods, combining an iterative design process with input from clinicians in simulations, and focus groups of clinicians and consumers.

Setting: Department of Women's and Children's Health and Department of Medical Physics and Clinical Engineering, University of Liverpool, UK.

Methods: A multidisciplinary team developed the design, using an obstetric manikin. Clinician and consumer groups also gave input on the concept and design. A healthcare product company and prototype manufacturer provided input into strategy, design and manufacture.

Results: The PPH Butterfly is a single piece, plastic medical device that replicates BMC. It is designed to be easy to use and low-cost and allows for smooth insertion and removal. It is acceptable to clinicians and consumers and performs well in tests.

Conclusions: This is the first device designed to replicate BMC while being less invasive. It could potentially be an effective form of PPH management, while also diagnosing the source of the bleeding. The device will now be tested in humans.

Keywords: Bimanual Compression; PPH Butterfly; Postpartum Haemorrhage; Treatment; Uterine Atony.

Figure 1

A composite picture combining a shelf pessary (used for the treatment of uterovaginal prolapse) and a Cusco speculum (used for vaginal and cervical examination).

Figure 2

Diagram showing the normal progression of severe PPH. Use of the PPH Butterfly should provide an early diagnosis of the underlying cause of the bleeding while preventing on-going blood loss. PPH, postpartum haemorrhage.

Figure 3

The platform of the PPH Butterfly rests just beneath the uterine cervix (shown as a red dotted line above). Bleeding from above the red line is usually due to uterine atony and will stop abruptly with uterine compression. That from below the red line is from vaginal lacerations and blood loss will continue even with uterine compression. PPH, postpartum haemorrhage.

Figure 4

First design using hand cream bottle and asthma spacer.

Figure 5

A shelf pessary.

Figure 6

The final design of the platform.

Figure 7

The PPH Butterfly being inserted into the manikin (previous design of the device). PPH, postpartum haemorrhage.

Figure 8

Design diagram showing original dimensions of the PPH Butterfly once folded for use. PPH, postpartum haemorrhage.

Figure 9

The original design from which the name PPH Butterfly originated. The two wings on either side of the platform fold together for insertion, opening up once within the vagina. Channels on the surface of the wings direct blood down into the drainage channel that runs through the centre of the handle. PPH, postpartum haemorrhage.

Figure 10

A variety of platform designs (in chronological order from left to right) showing the evolution of the design.

Figure 11

This iteration has a compression gauge as part of the central pillar supporting the platform (note the draft pulley system, designed to pivot the platform from a longitudinal position for insertion into a horizontal position for use).

Figure 12

The initial hinge design—strong but with a sharp leading edge that could result in trauma on insertion.

Figure 13

The redesigned shorter hinge. The sharp edges of the folded living hinge are now recessed behind extensions to the platform. Once folded for use, each arm has two pedicles lateral to the hinge that rest over the outer edges of the platform. As soon as the hinge starts to ‘give’ with pressure, these pedicles push tight against the platform thus ensuring strength and stability.

Figure 14

(A–D) The final iteration of the device. The device is folded flat for insertion (A) and then the handles brought together so as to create a stable triangular structure to support the weigh-bearing platform (B). The handles are held together by complimentary protrusion and recesses in the handle as well as by the finger grips. The device can be held in a longitudinal fashion (C) to mimick standard bimanual compression. For women lying on a bed, the handle can be stabilised from above (D) so as to wedge the handle onto the bed. This mechanism should be less tiring for the clinician as he/she can use their body weight to put pressure on the uterus as well as to hold the device in position.