The hTEE system for transoesophageal echocardiographic monitoring of haemodynamic instability

Three studies were identified that used the haemodynamic transoesophageal echocardiography (hTEE) system to monitor haemodynamic instability in critical care: 1 prospective observational study (n=94), 1 case series (n=21) and 1 case report (n=1). None reported patient outcome measures and evidence on clinical effectiveness is currently lacking.

The observational study demonstrated that when used by suitably skilled and experienced operators, the hTEE system provided relevant haemodynamic monitoring information, which had a clinical impact in most patients.

No clinical studies have directly compared the hTEE system with conventional transoesophageal echocardiography.

Two clinical trials of the hTEE system were identified, 1 which has completed and 1 which is ongoing. Both focus on patient outcome measures.

The observational study reported minor gastric bleeding without clinical consequence in 2 patients. In addition, 2 patients developed a mechanical ulceration of the superior lip, caused by prolonged contact with the probe.

The authors of the case series reported that, to date, they have used more than 200 individual ClariTEE probes (part of the hTEE system) in the cardiovascular intensive care unit and over 50 elsewhere with no complications.

The average cost of consumables per hTEE use is £750, with additional costs arising from capital investment in the system, training and maintenance.

Training needs for all intensive care physicians will have a cost and resource impact. However, no published evidence was found on the NHS costs of adopting the technology or resource consequences.

In the observational study, malfunction of the ClariTEE probe precluded further imaging in 2 patients who had already been monitored for 48 hours.

Haemodynamic evaluation was not possible in the observational study in 15% of patients. The authors attributed this to the technical limitations of the ClariTEE probe (its being single-patient use and miniature).

With appropriate training, intensive care physicians can conduct both qualitative and semi-quantitative hTEE assessment as an adjunct to conventional haemodynamic monitoring.