Comparison of efficacy of local anesthetic solution, distilled water and normal saline as emergency fixatives

Adequate tissue fixation is fundamental to good quality histological sections. Owing to undesirable effects of 10% buffered formalin, its availability in clinics is questionable. Thus, the present study was conducted with a novel approach to fixation, together with the scope of finding fixative properties of more commonly used reagents available at the clinics.

The present study was aimed to compare the efficacy of local anesthetic solution, normal saline (NS) and distilled water (DW) with that of 10% neutral-buffered formalin.

It is a single-blinded study where histological assessment of fixation was done to assert if the tissues procured were sufficient or insufficient for the clinical diagnosis with/without any problems.

Forty soft-tissue specimens obtained from 2 goat tongue were used. Tissues each were directly immersed in local anesthesia, DW, NS solution and formalin for 12 and 24 h each and labeled as Group I and Group II, respectively. The sections were evaluated for staining quality and were subjected to statistical analysis.

Kruskal-Wallis test was employed to assess the differences in histological quality scores. Comparison between the tissues of the two groups was estimated with Mann-Whitney U-test. Kappa Statistic was used to measure the interobserver variation.

There was a significant difference (P ≤ 0.05) in the efficacy of all the three emergency fixatives.

On the basis of the results obtained, local anesthetic solution can be used as an emergency fixative.