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                                                                    Exhibit 99.1


                                                            David T. Giddings
                                                            Chairman/CEO
                                                            Larry Betterley, CFO
                                                            651-639-8035
                                                                     or
                                                            Craig Shinbaum
                                                            Stern & Co.
                                                            (212) 888-0044

For Immediate Release:
----------------------

         Diametrics Medical Announces Preliminary First Quarter Results

                Conference Call To Be Broadcast Over the Internet


ST. PAUL, Minn., April 20, 2001 - Diametrics Medical, Inc. (Nasdaq: DMED) today
announced it expects revenue for the first quarter ended March 31 to be
approximately $5.7 million compared to $5.6 million in the same period a year
ago. The company expects its net loss for the quarter to be approximately $1.2
million, or $0.04 per share.

"Sales of our intermittent testing products were at record levels this quarter,
growing more than 45% from last year's first quarter," said David T. Giddings,
Diametrics' Chairman, CEO and President. "Sales of our continuous monitoring
products were down, however, as a result of slow economic conditions and other
events. The market for continuous monitoring products is less developed than
that for intermittent testing products, making the product line more sensitive
to external influences and economic conditions."

Diametrics' continuous monitoring products consist of the Trendcare(R)
Continuous Blood Gas Monitoring System, including Paratrend(R) sensors for use
with adult and pediatric patients and Neotrend(TM) sensors for neonatal
patients, and the Neurotrend(TM) Cerebral Tissue Monitoring System. The
intermittent testing product line consists of the IRMA(R)SL Blood Analysis
System utilizing disposable electrochemical cartridges and accessories, and
IDMS(R) data management software.

"Diametrics is pleased with its progress in business and product development and
remains confident in the long term outlook for the company. However, we are
currently operating in an environment of uncertainties and changes that are
impacting our near term financial results. These uncertainties include the
impact of new product introductions on sales of existing hardware product lines,
reduced capital spending in the healthcare sector, the general economic
slowdown, and the transition of the distribution channel as a result of the
pending sale of Agilent's healthcare business to Royale Philips Electronics,"
said Giddings. "These uncertainties are temporary and we believe they will be
resolved over the next few quarters."
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Diametrics plans to issue first quarter results for fiscal year 2001 before the
open of market trading on Wednesday, April 25, 2001. The company will broadcast
live via the Internet its first quarter conference call the same day at 10:00
a.m. Eastern Time at http://www.vcall.com. The company plans to discuss details
of its first quarter results and outlook at that time. To listen to the live
call, please go to vcall.com approximately thirty minutes before the conference
call is scheduled to begin. You will need to register as well as download and
install any necessary audio software. A replay of the call will be available for
90 days.

Agilent Technologies, Inc. is the exclusive global distributor of Diametrics
Medical's leading critical care products, the IRMA SL Blood Analysis System, and
the Trendcare Continuous Blood Gas Monitoring System, including Paratrend and
Neotrend. CODMAN, a Johnson & Johnson company, is the exclusive worldwide
distributor of Diametrics' Neurotrend Cerebral Tissue Monitoring System.
Neurotrend, continuously monitors oxygen, carbon dioxide, acidity and
temperature in brain tissue or fluids, providing critical information to guide
clinicians and surgeons in treating patients with severe head trauma or those
requiring surgical intervention in the brain.

Diametrics Medical, Inc. is a leader in critical care technology. The company is
dedicated to creating solutions that improve the quality of healthcare delivery
through products and services that provide immediate, accurate and
cost-effective time critical blood and tissue diagnostics. Additional
information is available at the company's Web site, http//www.diametrics.com.

Statements regarding the company's expectations about new and existing products,
future financial performance and other forward looking statements are subject to
various risks and uncertainties, including, without limitation, demand and
acceptance of new and existing products, technology advances and product
obsolescence, competitive factors, and the availability of capital to finance
growth. These and other risks are discussed in greater detail in the company's
filings with the Securities and Exchange Commission.
