Paradoxical and venous Gas Embolism During Hysteroscopic Surgery Detected by Trans Esophageal Echocardiography: A comparison using either bipolar or monopolar diathermia

We have observed severe venous air and paradoxical gas embolism using
trans-oesophageal echocardiography (TOE) in a patient without a patent foramen
ovale undergoing bipolar trans cervical resection of the endometrium. Although
venous emboli during monopolar hysteroscopic surgery is a common finding, its
association with paradoxical embolism has not been reported before. Whether
bipolar diathermia, in contrast to monopolar diathermia, induces more venous
and paradoxical gas embolism is unknown and therefore subject of our study.

To determine the incidence and grade of venous emboli and/or paradoxical gas
emboli during hysteroscopy surgery using TOE. In addition, a comparison will be
made using either bipolar or monopolar diathermia. Knowing the incidence and
severity of embolic events may help in understanding the pathophysiology and
thereby help in preventing these potentially lethal events.

After receiving informed consent patients will be included in a randomised
study using either monopolar or bipolar diathermia. The ultra sound probe will
be positioned into the oesophagus to obtain a four chamber view. Rating of
intra-operative embolic events will be performed by a blinded observer using
established criteria.

monopolar versus bipolar diathermia

Adverse and serious adverse events related to the hysteroscopic procedure will
be treated according to generally accepted guidelines.
First off all the hysteroscopic procedure is stopped thereafter the primary
goal is the protection and maintenance of vital functions. Measures may include
cardiopulmonary resuscitation.

The reported overall morbidity (0.2%) and mortality (0%) rates of
intraoperative transesophageal echocardiography (TEE) were determined in a
retrospective case series of 7200 adult, anesthetized cardiac surgical
patients. The most common source of TEE-associated morbidity was odynophagia
(0.1%), which resolved with conservative management. These results suggest that
TEE is a safe diagnostic tool for the management of surgical patients.
If any adverse and serious events (SAE) related to the installation of the TOE
probe occur (oesophageal lacerations, bleeding etcetera) they will be treated
following consultation of a gastroenterologist and surgeon.

All adverse events reported spontaneously by the subject or observed by the
investigator or his staff will be recorded.
A serious adverse event is any untoward medical occurrence or effect that at
any dose results in death;
- is life threatening (at the time of the event);
- requires hospitalisation or prolongation of existing inpatients*
hospitalisation;
- results in persistent or significant disability or incapacity;
- is a new event of the trial likely to affect the safety of the subjects, such
as an unexpected outcome of an adverse reaction, lack of efficacy of an IMP
used for the treatment of a life threatening disease, major safety finding from
a newly completed animal study, etc.

All SAEs will be reported to the accredited METC that approved the protocol,
according to the requirements of that METC.