Comparing volumetric and biochemical assessment of intravasation caused by hysteroscopic surgery.

BACKGROUND: During hysteroscopic surgery intravasation of irrigation fluid occurs, leading to potentially dangerous intravascular fluid overload. Currently, intravasation is usually measured volumetrically as fluid deficit. Intravasation could also be calculated using the decrease in hemoglobin or increase in chloride ion concentration, both phenomena known to result from intravasation. We compared the values of intravasation measured volumetrically as fluid deficit versus calculated from the biochemical change in hemoglobin and chloride. We expected that these values would show strong correlation and agreement. METHODS: In a retrospective data analysis of 51 patients who underwent hysteroscopic resection of myomas or endometrium a pre and post procedure concentration of haemoglobin and chloride was available. The fluid deficit was plotted against the two versions of calculated intravasation. Furthermore, we put the data into Bland-Altman plots to scrutinize their relationship. RESULTS: The volumetric assessed fluid deficit and both versions of biochemically assessed intravasation, either using the change in hemoglobin or chloride ion concentration, turned out to be three totally different entities with weak correlation. Bland-Altman plots show too wide limits of agreement, and a striking difference between the two methods of calculated intravasation. CONCLUSION: Our study shows significant differences and poor agreement between volumetric and biochemically assessed intravasation. Based on this study, routinely assessing intravasation by biochemical methods does not have additional benefit compared to the volumetric fluid deficit. It remains unclear which method resembles true intravasation.

The HYSTER study: the effect of intracervically administered terlipressin versus placebo on the number of gaseous emboli and fluid intravasation during hysteroscopic surgery: study protocol for a randomized controlled clinical trial.

BACKGROUND: Transcervical resection of myoma or endometrium is a safe, hysteroscopic, minimally invasive procedure. However, intravasation of distension fluid is a common phenomenon during these procedures. In a previous study we observed venous gas emboli in almost every patient. The severity of hysteroscopic-derived embolization has been shown to be correlated to the amount of intravasation. In addition, paradoxical gas embolism, which is potentially dangerous, was observed in several patients. Studies have shown a reduction of intravasation by using intracervically administered vasopressin during hysteroscopy. We think that its analog, terlipressin, should have the same effect. In our previous research we observed more gaseous emboli as intravasation increased. Whether or not the insertion of intracervically administered terlipressin leads to a lower incidence and severity of gas embolism is unknown. We hypothesize that intracervically administered terlipressin leads to a reduction of intravasation with a lower incidence and severity of gas embolism. Terlipressin may be of benefit during hysteroscopic surgery. METHODS/DESIGN: Forty-eight patients (ASA 1 or 2) scheduled for transcervical resection of large, types 1-2 myoma or extensive endometrium resection will be included. In a double-blind fashion patients will be randomized 1:1 according to surgical treatment using either intracervically administered terlipressin or placebo. Transesophageal echocardiography will be used to observe and record embolic events. A pre- and post-procedure venous blood sample will be taken to calculate intravasation based on hemodilution. Our primary endpoint will be how terlipressin influences the severity of embolic events. Secondary endpoints include the effect of terlipressin on the amount of intravasation and on hemodynamic parameters. DISCUSSION: If terlipressin does indeed reduce the number of gaseous emboli and intravasation occurring during hysteroscopic surgery, it would be a simple method to minimize potential adverse events. It also allows for prolonged operating time before the threshold of intravasation is reached, thereby reducing the need for a second operation. TRIAL REGISTRATION: Nederlands Trial Register (Dutch Trial Register), ID: NTR5577 . Registered retrospectively on 18 December 2015.