Abstract 106: Covid-19 Pandemic Impact on Ems Runs and Resuscitation Attempts

Background: The frequency of EMS runs, resuscitation attempts, & out of hospital cardiac arrest survival within a pandemic period has not been studied within the Detroit and metro Detroit region in Michigan. To analyze and study the consequences associated with the spread of COVID-19 within two Michigan counties, a retrospective review from two different medical control authorities (MCA) was completed. We hypothesized the number of out of hospital cardiac arrests and EMS runs to increase during the COVID-19 pandemic, while resuscitation attempts to decrease. Methods: This is a retrospective review study. Records from two MCAs, the Detroit East Medical Control Authority (DEMCA) and the Macomb County Medical Control Authority (MCMCA), were utilized and data was extracted and extrapolated. Each of these MCAs oversee Emergency Medical Services (EMS) within their respective counties. DEMCA provides coverage for the eastern region of Wayne County and MCMCA serves all of Macomb County. Runs, dead-on-scene numbers, & resuscitation attempts were each assessed from March through May of 2019 & 2020. Results: There were nearly double the number of EMS runs for out of hospital cardiac arrest during the 3 main months of the pandemic. In March through May 2020 there were 1756 runs with a mean age of 62.7 years vs. 988 runs during the same period in 2020 with a higher mean age of 65.1 years (p<0.01). This difference was most pronounced in April, which was the height of the pandemic in Michigan (782 vs. 312). The higher number of EMS runs was also more pronounced in Wayne county (1.86 times 2019 numbers) compared to Macomb County (1.65 times 2019 numbers). Resuscitation was attempted on 566 (32.2%) during the pandemic compared to 222 (22.5%) during the same period in the prior year (OR 0.61, 95% CI 0.51 - 0.73, p<0.01). The proportion of patients transferred from the field to an ED did not change significantly (2.6% in the control period vs. 2.1% during the pandemic, p=0.325). Conclusion: There was a 1.78 fold rise in out of hospital cardiac arrest EMS runs during the peak months of the pandemic in metro Detroit compared to the same period in 2019. Despite national concerns on the safety of resuscitation with Covid-19, a higher proportion of patients had resuscitation attempted during the pandemic.

Gas Turbine Compressor Unit Repowering

This paper presents how a major U.S. gas transmission and storage company restored gas storage peaking capacity by repowering obsolete gas turbine compressor units. Consumers Power Company’s Ray Field located in Macomb County, Michigan, USA, was developed as a 44 BCF working capacity gas storage field in 1966. Due to the high deliverability, the field is operated as a peaking reservoir, handling rates as high as 500 MMCFD on injection and 1,200 MMCFD on withdrawal. Ten (10) 2,750 horsepower gas turbine driven 4-stage centrifugal compressor units were installed in the mid to late 1960’s at the field. The compression is operated 2, 4 and 8 stage, as needed, to cover storage pressures of 450 to 1800 psig. Each centrifugal compressor is driven by a Pratt Whitney (PW) GG-12 Gas Generator firing into a Cooper-Bessemer (CB) RT-27 Power Turbine. By 1980 parts and maintenance services for the PW GG-12 Gas Generator became very expensive to non-existent. Aircraft use of the GG-12 (JT-12) had been phased out. Consumers Power, with 13 of these turbines on their system, was becoming the only remaining user. In the mid 1980’s four (4) of the Ray Field gas turbine compressor units were replaced with two (2) 6,000 horsepower reciprocating engine compressor units. These replacements maintained the deliverability of the field and provided salvageable engines and other parts to maintain the six (6) remaining turbines. However, by 1993 maintenance parts returned as a major problem as well as unit availability on the 6 remaining turbine units. In 1994 Consumers Power committed to a gas turbine unit repowering program as the preferred choice over unit replacement. Two (2) refurbished Solar Centaur T4500 Gas Turbine drives were purchased and installed to repower 2 of the obsolete turbine units. These installations have been very successful. Existing compressors, foundations, piping, coolers and auxiliary systems were re-used with only minor modification. The complete installed cost for repowering was about 33% of the cost experienced for replacement. Installation was completed within eight (8) months of project commitment. The low emission rates from the Solar SoLoNOx Combustors allowed short lead time (6 months) on air emissions permit. New sound attenuation enclosures met the new local noise ordinance and replaced equipment that had been a source of local complaint. PLC based controls improved reliability and flexibility of operation. The additional horsepower available from the T4500 Turbine (4,300 vs 2,750) allows for increased future capacity. Because of the success of the Ray Turbine Repowering Project, Consumers Power has committed to 2 more refurbished Solar Centaur T4500 Units to repower PW/CB Turbines at the St Clair Compressor Station. Solar is scheduled to delivery these 2 units by year-end 1995 for installation in 1996.