Advanced 2020 FAQ's

Q1: Our electrolyte analyzer provides a calculation of osmolality; why should we consider purchasing a dedicated instrument for this test?

A1: Most electrolyte analyzers provide a calculated osmolality that may correlate with the measured value on healthy patients. In emergency cases, however, delta osmolality (or osmol gap) gives the physician a first indication of a toxic event and the ability to closely monitor its resolution. A delta osmolality of 40 points over 24 hours, may be life threatening. Be aware that freezing-point is the method of choice for gap determinations. Vapor pressure is insensitive to volatile solutes, and will not register alcohol, ethylene glycol, ketones or other important osmocontributors.

For more information on osmol gaps, consult the following:
Bhagat, C.I., Garcia-Webb, P., Fletcher, E., Beilby, J.P. Calculated versus Measured Plasma Osmolalities Revisited. Clinical Chemistry, 30(10):1703 1984
Boyd, D.R., Mansberger, A.R., Serum Water and Osmolal Changes in Hemorrhagic Shock: An Experimental and Clinical Study, Am Surgeon, 34: 744 (1968)
Dorwart, W.V., Chalmers, L., Comparison of Methods for Calculating Serum Osmolality from Chemical Concentrations, and the Prognostic Value of Such Computations, Clinical Chemistry, 21: 190 (1975)
Eskew, L., Speicher, C.E., Using Anion and Osmolal Gaps to Diagnose the Cause of Intoxication, Diagnostic Medicine, p. 6 February 1985
Evans, J.R., Osmolal Gaps in Urine, Clinical Chemistry, 32(7): 1415 (1986)
Evans, J.R., Yet More on Osmolal Gaps in Urine, Clinical Chemistry, 33(5): 736 (1987)
Garg, A.K., Nanji, A.A., Osmolar Gap, Diagnostic Medicine, p. 38 Mar/Apr 1982
Neary, R.H., More on Osmolal Gaps in Urine, Clinical Chemistry, 32(12): 2225 (1986)
Soloway, H.B., What is an osmotic gap, and how is it used in diagnosis?, Diagnostic Medicine, p. 20 Nov/Dec 1983
Speicher, C.E., Anion and Osmolal Gaps, Consultation Casebook, Pathologist, 2: 117 (1984)
Weisberg, H.F., Osmolality: Calculated, "Delta" and More Formulas. Clinical Chemistry, 21: 1182 (1975)

Q2: Why should I purchase an osmometer; what can osmolality provide that other tests cannot?

A2: Freezing-point osmometers measure the number of particles in solution with millimole sensitivity. Osmolality is not affected by the size, shape or charge of particles and is less influenced by suspended particles (i.e. particles not in solution). Therefore, by using osmolality in conjunction with other tests (i.e. specific gravity, etc.) you can often clarify or pinpont a diagnosis more quickly. Osmolality also enables you to monitor the stability of patients in critical condition STAT, easily and accurately; modifications can be made in their support systems quickly, before irregularities become life threatening.

Q3: You specify your calibration is "automatic". What exactly does that mean?

A3: By automatic calibration, we mean that the user simply runs tests of calibration standards. Multiple tests are required to determine reproducibility. The instrument's microprocessor will then adjust the instrument to the new values. The user is not required to adjust the calibration manually or intervene in any other way during calibration.

Q4: How can the "no maintenance" features of your osmometers save me time and aggravation?

A4: Advanced and Fiske micro-osmometers feature completely dry, solid-state cooling assemblies. It is not necessary for the user to monitor levels of cooling liquid (as is required of many osmometers now on the market). Moreover, because of the state-of-the-art design, these instruments can be up and running virtually from 'Power On', giving you STAT ready, immediate access.

Q5: What are the advantages for using disposable sample tubes with the your Osmometers?

A5: Convenient, safe and efficient, these sample tubes have been customized to provide you with reliable, accurate testing. Disposables have become a standard in the majority of the world's leading hospitals as they are considered safer (virtually eliminating cross-contamination), more environmentally friendly (eliminating washing and related power, waste-water, etc) and efficient.

Q6: What is the typical life span of an osmometer?

A6: This is a question that is often posed by Lab Managers interested in how to write-off a capital expenditure over time or by an Insurance Company looking to settle a claim. We generally state that the serviceable live of a Fiske Osmometer is 5 years. In some countries, the lowest acceptable life expectancy is 7 years - the chief challenge to extending the life span to 7 years would be the cooling assembly (see below).

Q7: How can I be sure that no carry-over occurs in multi-sample osmometers?

A7: While single-sample osmometers specify that the user should wipe the probe between tests, automated walk-away systems, like the Fiske 2400 and the Advanced 3900 have a wiping step designed into the test protocol. In the case of the Fiske 2400, the probe is cleaned by positive displacement by a super-absorbent probe wiper disc. Carry-over and cross contamination are automatically eliminated when the sample probe, the only part of the instrument touching the sample, pierces the wiper disc in an interim step between each of the 20 test positions.