Evaluation of Efficacy of Different Identification Tests to Distinguish Cerebrospinal Fluid from Local Anaesthetic Solution: A Comparative Study
Background: Local anaesthetics (LAs) are used clinically for anaesthesia and analgesia either following surgery or for management of other acute and chronic pain conditions; they only last a few hours. Various methods have been mentioned in the past literature for differentiating the CSF and the local anaesthetic solutions. Hence; we planned the present study to check and compare the efficacy of simple identifications tests to distinguish local anesthetic solutions from CSF.
Materials & Methods: We planned the present study to compare the efficacy of simple identifications tests to distinguish local anesthetic solutions from CSF. We involved five experienced anesthetists for the present study. Both the anesthetics were asked to identify 0.1 ml sample of bupivacaine and mock CSF (tap water) by each of four physicochemical characteristics based on criteria: Temperature, pH, Presence of glucose, and Turbidity when mixed with thiopentone. The anesthetics involved in the present study were unaware of the results. All the results were recorded on excel sheet and were analyzed by SPSS software.
Results: The two test solutions were identified conveniently together with the four physiochemical tests. However; the anesthetics were not able to identify and differentiate the solutions clearly with individual tests. Conclusion: Anesthetist should be accustomed with different physicochemical methods available for differentiating between CSF and local anaesthetic solution. However; no single test appears to have complete reliability. Therefore, combinations of tests must be used.
2. Denkler K. A comprehensive review of epinephrine in the finger: to do or not to do. Plast Reconstr Surg. 2001;108:114–24.
3. Hillerup S, Bakke M, Larsen JO, Thomsen CE, Gerds TA. Concentration-dependent neurotoxicity of articaine: an electrophysiological and stereological study of the rat sciatic nerve. Anesth Analg. 2011;112:1330–1338.
4. Schiffer E1, Van Gessel E, Fournier R, Weber A, Gamulin Z. Cerebrospinal fluid density influences extent of plain bupivacaine spinal anesthesia. Anesthesiology. 2002 Jun;96(6):1325-30.
5. Hillerup S, Jensen RH, Ersboll BK. Trigeminal nerve injury associated with injection of local anesthetics: needle lesion or neurotoxicity. J Am Dent Assoc. 2011;142:531–539.
6. Haas DA, Lennon D. A 21 year retrospective study of reports of paresthesia following local anesthetic administration. J Can Dent Assoc. 1995;61:319–330. [PubMed]
7. Garisto GA, Gaffen AS, Lawrence HP, Tenenbaum HC, Haas DA. Occurrence of paresthesia after dental local anesthetic administration in the United States. J Am Dent Assoc. 2010;141:836–844.
8. Waters JH1, Rizzo VL, Ramanathan S. A re-evaluation of the ability of thiopental to identify cerebrospinal fluid in epidural catheter aspirate. J Clin Anesth. 1995 May;7(3):224-7.
9. Knudsen K. Coloured chlorhexidine cotton pads may help to identify cerebrospinal fluid during epidural or spinal anaesthesia. Acta Anaesthesiol Scand. 2006 Jul;50(6):685-7.
10. Soliveres Ripoll J1, Sánchez Morillo J, Balaguer Doménech J, Gallen Martín L, Sánchez Hernández A, Solaz Roldán C. Quantitative test to distinguish spinal fluid from saline solution in combined spinal-epidural anesthesia. Rev Esp Anestesiol Reanim. 2009 Apr;56(4):206-11.
11. Imbelloni LE1, Gouveia MA, Cordeiro JA. Continuous spinal anesthesia versus combined spinal epidural block for major orthopedic surgery: prospective randomized study. Sao Paulo Med J. 2009 Jan;127(1):7-11.