X-Message-Number: 2555
Subject: CRYONICS.SCI Alcor Builds New MALSS
Date: Fri, 14 Jan 94 11:22:28 PST


     The Alcor Foundation has constructed a new and considerably improved 
Mobile Advanced Life Support System (MALSS).  Since 1987, Alcor has used 
the MALSS built and owned by Cryovita Laboratories.  Planning for a new 
unit had been in progress for over a year and many of the parts had been 
acquired; however, construction did not begin in earnest until late 1993 
(when Cryovita informed us that it would be ending our agreement for the 
use of theirs).

     The purposes and definition of a MALSS were described in the March, 
1987 issue of *Cryonics* as: 

          "...an easily transportable, fully self-contained extracorporeal 
     perfusion and cooling unit for use in the transport of biostasis 
     patients.  The objectives to be met in the design of this unit were 
     that it be readily transportable, relatively straightforward to 
     operate, fully self-contained in terms of power requirements and 
     supporting supplies (disposables, surgical instruments, medications, 
     etc.), and that it be capable of meeting the normothermic metabolic 
     demands of the average adult.

          "The primary purpose of the MALSS is to allow for field 
     cardiopulmonary support by extracorporeal perfusion.  However, 
     because of the necessity to await the pronouncement of clinical death 
     imposed by current legal constraints, preparation of the patient for 
     extracorporeal support must begin after respiratory and cardiac 
     arrest.  In order to minimize ischemic damage during the interval 
     between pronouncement of legal death and the start of extracorporeal 
     support it is necessary to administer CPR.  While it is anticipated 
     that under most circumstances femoral cutdown and initiation of 
     bypass can be undertaken with 15 to 30 minutes of legal death, it is 
     still necessary to have mechanical adjuncts for CPR available in 
     order to maximize use of the extremely limited number of personnel 
     available in a field setting."

     The first MALSS, constructed in 1986 at Cryovita Laboratories (Note: 
Until 1992 Cryovita Laboratories and Alcor were closely associated and in 
the same buildings.) by Jerry Leaf, Hugh Hixon and Mike Darwin, has gone 
through a number of major modifications.  It began life as a Travenol Life 
Support Gurney, with an aluminum frame, an integral Brunswick HLR, two "E" 
oxygen cylinders, three storage drawers, and a mount for a cardiac 
monitor/defibrillator.  At that time we added a blood pump, batteries, a 
charger, and an air compressor/vacuum pump.  This equipment load caused 
the frame to bend alarmingly, and part of the frame was replaced with 
steel.  More recently, the wheels were replaced because they were failing 
under the weight of the MALSS.  Later modifications were the replacement 
of the Brunswick HLR with the more effective Michigan Instruments HLR, the 
mounting of an ice bath, and a system for circulating ice water over the 
patient.  Eventually, its ready-to-go weight reached 510 lbs., to which 
would be added the weight of the patient and the ice load.  "Easily 
transportable" was a fantasy until Alcor added a custom lift gate to its 
ambulance.  This "Mark 1" MALSS is currently being modified by Cryovita to 
approximately a Mark 1, Mod 3 version.

     The MALSS recently completed at Alcor, dubbed the "Mark 3", is the 
logical extension of the original Mark 1, done on a clean slate.  We have 
succeeded in implementing many major (and minor) improvments while giving 
up relatively little:

* The new steel frame is not only stronger and more durable than the 
aluminum, steel and PVC tubing combination of the original, it was custom 
designed and constructed around essential features of the whole unit (form 
follows function!).  And it is designed to integrate into the ambulance.

* The frame is constructed such that the 7'1" ice bath can be shortened by 
nearly a foot on the spot.  (A tight elevator ride on one patient 
transport convinced us that this is a good idea.)  Because of the steel 
frame, the PIB has a larger internal capacity, despite almost identical 
external dimensions.

* All components are secured within the frame profile: this prevents 
the perfusion circuit and equipment from being scraped off going through 
doorways and from the inevitable collisions with walls and furniture.  The 
consequence of this is that the perfusion tubing circuit can be strung 
when time is less critical, in advance of the pronouncement of the 
patient's legal death.

* The control panel and blood pump placement are designed to ease 
stringing of the pump.  The perfusion circuit mounting board can be swung 
out for stringing and locked back within the profile (while strung), again 
reducing preparation time.

* With the more efficient configuration of equipment, more on-board 
storage capacity is available in large-capacity removable drawers.

* The oxygen cylinders hold 7,000-liters of oxygen (compared to 1,256 
liters previously).  This gives the HLR of the Mark 3 an unsupported 
endurance of about an hour.  This can be readily extended by connecting 
the MALSS to hospital oxygen, the ambulance oxygen system, or separate 

* The Mark 3's electrical components use all 110 volt power, supplied 
either from the wall or from a 1200 watt inverter powered by an 80 ampere-
hour, 12 volt gel battery; or by the ambulance 12 volt system.  This is a 
major improvement over the perverse and inflexible 12/24 volt system 
demanded by the 24 volt roller pump of the Mark 1 and allows the Mark 3 to 
be fully supported by the ambulance.  An on-board ammeter allows 
estimation of battery drain.

* The icewater circulating pump pumps faster, and the distribution system 
contains improvements recommended by Alcor member Robert Cardwell, such as 
non-splashing flow spreaders.

* The orientation of the original MALSS with the patient's head at the 
rear of the ambulance has been corrected so that activities in the 
ambulance are a lot easier.  Also because of this, the ambulance lift gate 
has been shortened 17", easing the strain on its mounts.

* And finally, the professional paint job is not only durable, it makes 
the Mark 3 MALSS look very professional!  (Credit to Mike Darwin for 
suggesting powder coating.)

     These advances did not come without some sacrifices: Unassisted 
battery endurance is less (about an hour and a half under full load); 
however, we have never experienced, nor do we expect, a MALSS transport 
where the trip from the point of disconnection from AC power to the 
ambulance -- or vice versa -- would take more than a few minutes.  Due to 
a design error, the wheels are smaller than preference (by 2"), but they 
yield more manueverability than we had with the original model because 
they are not overstressed.  Finally, the Mark 3 weighs more than the 
original (625 lbs. vs. 510).

     The Mark 3 MALSS was designed and built entirely in-house at Alcor.  
Tanya Jones, Scott Hermann, and Keith Henson were major contributors to 
the effort which was spearheaded by Hugh Hixon.  Hugh also gets many 
thanks for having advanced the most of the cost out of pocket (this 
allowed the project to proceed without regard to transient cash flow 
concerns).  Hugh also purchased the equipment for a small but complete 
welding shop in aid of this and other development and prototyping projects 
at Alcor.  One of these is a much-improved portable ice bath (PIB) design.

     (Historical note: The "Mark 2 MALSS" is an uncompleted unit built by 
Keith Henson.  Its salient points are its organization into separate 
components (of an ice bath, mechanical section, and dolly) to make it 
transportable in a station wagon, and, more important, its welded steel-
frame construction.  As funds become available, this unit will be 
completed and deployed in Northern California.)

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