Pulse Oximeters

Pulse Oximeters are monitors that provide real-time measurement of a patient’s pulse rate and arterial oxygen saturation (the oxygen-carrying capacity of the blood’s hemoglobin, expressed as a percentage; normal is in the high 90’s). A disposable or reusable probe is placed on the patient’s finger (optional probes can be used on ear or tongue for some units.) The probe emits an infrared light from one side of the finger and captures the residual light that passes through the finger on the other side. The probe transmits this data to the monitor, which calculates the oxygen saturation of the blood. Used for patients with respiratory problems, and is required by law whenever a patient is under anesthesia. Note that these pulse oximeters measure Functional oxygen saturation, which is oxygenated hemoglobin expressed as a percentage of the hemoglobin that is capable of transporting oxygen. In contrast, some other laboratory instruments, such as blood gas analyzers or CO-oximeters, report Fractional oxygen saturation, which also measures dysfunctional hemoglobin. It is therefore not likely that the readings from these devices and the ones on a pulse oximeter will agree.

Invivo 4500+ Pulse Oximeter

Invivo 4500+ Pulse Oximeter

The Invivo 4500+ is a compact, portable pulse oximeter with an integral printer which produces up to 32 hours of oxygen saturation and pulse rate data on an easy-to-read printout. Runs both on AC power and can run on the internal rechargeable battery for up to two hours. Memory retains all monitor settings and trend data even when powered off. Audible pulse tone changes pitch higher or lower in response to saturation level fluctuations. Uses LED displays that are easier to read from any angle than the usual LCD displays found on similar monitors.

There are three software options available for the 4500+. The Plus 1 option includes a specialized software package which allows the extraction of trend data graphs, SaO2 data summaries and time-of-day histograms; this option is useful for sleep-study programs where recorded data needs to be studied by the clinician. The Plus 2 option has an interface cable (9398) which allows the use of both reusable and disposable Nellcor sensor products.This allows the customer to minimize alternate probe inventories.  The Plus 3 option has both the software package utilized in the Plus 1 option and the Nellcor interface available in the Plus 2 option.

Built-in RS-232 computer interface allows data transfer to a computer; analog outputs can send data to an exterior patient monitor. Built-in handle and high-impact plastic housing for portability and durability.

Suggested Substitutions: Nellcor N-180, N-200, N-290; Ohmeda 3740, Ohmeda 3760P, Healthdyne 950