Tomorrow Bio
By
Rebecca Ziegler & Dr. Emil Kendziorra
November 10, 2023
7 min reading

SST Procedure

This explanation of Tomorrow Bio's standby, stabilization, and transport (SST) procedures is based on standard cases. Exact procedures can vary depending on the circumstances of individual cases; not all possible variations will be included on this webpage. All costs associated with these procedures are included in every Tomorrow Bio plan. Procedures may update over time. 

SST Teams

SST teams at Tomorrow Bio consist of a core team of 3-4 personnel who perform the stabilization and cryoprotection procedure and an additional 1-2 personnel providing onsite logistics support. The core team consists of one Surgical Lead, one Assistant, one Perfusionist, and one Support personnel.  

New additions to SST teams must partake in multiple practice cases with medical body donors before participating in a case with a Tomorrow Bio member. Even after completing full training, all members of a SST team must partake in regular training with body donors as well as dry training to maintain SST skills or practice new SST equipment or procedures. 

Standby

Standby refers to the period when one of our medical SST teams is at the location of a member that is likely to pass away soon. While exact times of death are difficult to predict, most cases of death have some forewarning. Our SST teams are on call 24/7 to dispatch to a member in critical condition and wait onsite to begin the stabilizing procedures after legal pronouncement. This standby period can last for several days or even weeks. In cases of false alarms where the member's condition improves, the SST team may end standby and return if the prognosis worsens again, meaning that standby can occur multiple times per member.

In most cases, the SST team will dispatch to the member in one or even two of our Biostasis Ambulances that is specially equipped to handle full stabilization and cryoprotection procedures. If a member is outside of a reasonable driving range (which may depend on the prognosis), the team can dispatch by plane with all necessary equipment and with the ambulances following behind. In this scenario, the team will potentially require some local logistics support, most notably a vehicle to transport the body and a building where the procedure can be performed. These logistics are organized by onsite and/or remote Tomorrow Bio personnel. 

The standby period ideally includes communication between the SST team and the member's treating physicians (if the member is unconscious a Patient Advance Directive might be required, which we highly recommend) to ensure that the stabilizing procedures can begin as quickly after legal pronouncement as possible. 

Stabilization

This explanation does not include every detail about each step, but rather gives a broad overview of what is done. The following procedure outline is based on a case with four core SST personnel and assumes that the ambulance is seconds from the patient bed site. Each step represents actions that happen simultaneously or within seconds of each other. Steps that have low time variability will be accompanied by time estimates. 

  1. Three SST personnel put a soft stretcher (custom made by Tomorrow Bio to minimize insulation) under the patient and place the patient into an ice bath. The ice bath already contains a Lund University Cardiopulmonary Assist System (LUCAS) backplate and Surface Conduction Cooling Device (SCCD) tubing. In some cases, the ice bath may already contain water or a mixture of ice and water. The 4th personnel preps the ambulance (turns on the ambulance inverter, turns on the data logger, turns on the cerebral oximeter device, opens the oxygen valve and sets the oxygen flow, takes the LUCAS device out of its case and plugs it into power, takes the medication out of the cool box, removes cooled liquid bags out of the cool box and hangs them from the ambulance ceiling rails, holds the fabric scissors ready, etc).
  2. The ice bath is moved into an SST ambulance.
  3. The Surgical Lead turns on the water flow into the ice bath. If the patient is wearing clothes (insulation), fabric scissors are used to quickly remove all clothing.
  4. The Surgical Assistant and Support lift the patient to the side (onto the patient's right shoulder). The Surgical Lead inserts a rectal occlusion device (consisting of a cannula for colonic lavage and a temperature probe). The Perfusionist holds the LUCAS device ready for attachment. 
  5. The patient is laid onto their back and the LUCAS device is attached to the backplate and turned on selecting the continuous chest compression setting. 
  6. The Surgical Assistant straps the patient's right hand onto the LUCAS. The Perfusionist straps the patient's left hand onto the LUCAS. The Support shovels ice onto the patient, initially focusing on the head and groin.
  7. The Surgical Lead places an endotracheal/supraglottic airway device into the patient's airway and starts the ventilation machine. The Surgical Assistant and the Perfusionist each insert a temperature probe into one of the patient's ear canals and secures it with specialized wax. The Support continues to shovel ice.
  8. The Surgical Lead inserts a bone marrow needle into the patient's humeral head. The Surgical Assistant and the Perfusionist each place a cerebral oximeter probe onto each side of the patient's forehead and secures it with waterproof bandages. The support turns on the squid pump which circulates the ice water in the ice bath through the SCCD tubing.
  9. The Surgical Lead infuses medication (most importantly thrombolytic, antithrombotic and neuroprotective medications) through the bone marrow needle. The Support places an instrument tray onto the ice bath. The Surgical Assistant places surgical tools onto the instruments tray.
  10. All personnel put on PPE.
  11. The Support turns on the flow of the cool liquid bag that's attached to the rectal occlusion device (allowing for up to 5 liters of liquid to enter the colon). The liquid will be exchanged in intervals in a closed system setup to allow for optimal cooling.
  12. The Surgical Lead and Surgical Assistant perform an open peritoneal lavage access cut down and the peritoneal space is filled with pre-cooled liquid. The liquid will be exchanged in intervals in an open system setup to allow for optimal cooling.

Cryoprotection

If the patient is in close proximity to the European Biostasis Foundation's (EBF) facility in Rafz, Switzerland, then cryoprotection will take place after they have been transported to the facility. Otherwise, cryoprotection will take place in the ambulance once the patient's internal temperature has reached ≈20°C. The cryoprotection procedure for whole-body and brain-only patients is the same, except for the fact that (if possible) the descending aorta of a brain-only patient will be clamped after the median sternotomy so that cryoprotectant only flows to the top part of the body.

  1. The Surgical Lead and Surgical Assistant prepare all equipment for surgery and remove the LUCAS device. The Perfusionist primes the perfusion circuit with washout solution (MHP2). 
  2. The Surgical Lead and Surgical Assistant perform a median sternotomy to access the patient's heart. 
  3. The Surgical Lead and Surgical Assistant cannulate to the ascending aorta and secure the cannula with an adapted purse string suture technique. 
  4. All team members double check the perfusion circuit for bubbles. 
  5. The Perfusionist slows down the pace of the perfusion circuit pump. The Surgical Lead and Surgical assistant clamp and cut the arterial line and connect it to the aortic cannula under flow and without air bubbles entering the line. Once that is confirmed, the clamps are released and the perfusion starts. 
  6. The Surgical Lead and Surgical Assistant cannulate the right atrium with a two stage venous cannula and secure it with an adapted purse string suture technique. 
  7. The Surgical Lead or the Surgical Assistant attaches the venous line to the cannula. The Perfusionist increases the flow so long as pressure remains under 110 mmHg.
  8. After perfusing ≈27 liters of washout solutions, the Perfusionist begins adding cryoprotectant solution (VM-1 7%) into the perfusion circuit. In total, the patient is sequentially perfused with ≈21 liters of 7%, ≈21 liters of 14%, ≈21 liters of 43%, and up to ≈90 liters of 108%. The 7%, 14%, and 43% solutions are continuously kept at 4°C using the perfusion circuit’s heat exchange (cooling with ice-water mixture). The 108% is pre-cooled to -20°C and kept between -20°C and -40°C with the heat exchange (cooling with an anti-freeze coolant, dry ice mixture). 
  9. The Perfusionist regularly (ideally in 10 minute intervals) samples the patient's outflow and measures the refractive index (cryoprotectant concentration) using a refractometer. 
  10. The perfusion and cryoprotection is complete once the patient reaches a refractive index indicating target concentration or if the refractive index does not increase for an extended amount of time.

Transport

If the cryoprotection was performed remotely  in the ambulance before transport, the SST team packs the patient's body with dry ice (sourced locally by the logistics support). If only the stabilization took place inside the ambulance, the LUCAS device, ventilation, and ice-water continue to stabilize the patient while they are in transit to the facility (one member of the SST team, usually the Surgical Lead, remains in the back of the ambulance during transport).

If the SST team dispatched to the patient by plane, then the patients will be transported to the facility (through Zurich airport) by plane. For plane transport, the patient is placed in a Ziegler case that holds the patient at dry ice temperature (-79°C) or (pending further research) a new transport case developed by Tomorrow Bio.