I. Animal Preparation and Instrumentation:
1. Anesthetize the animal with telazol (5mg/kg) and xylazine (2mg/kg) at appropriate doses.
2. Transport the animal to the procedure area.
3. Place the animal under isoflurane targeting 1.0 MAC by facemask. Transition to generally 10 ccs/kg TV, RR of 12-14 initially but to a target of pCO2 30-45 and an FiO2 of 40% but adjusted appropriately as needed.
4. Place the animal in sternal recumbency and intubate the animal with a 7.0 endotracheal tube.
5. Turn the animal into dorsal recumbency and restrain.
6. Place all venous and arterial catheters using US guidance, and place all monitoring devices.
-place a 7 fr sheath in 2 of the following: either carotid or right brachial artery through which we will place the PV Loop through one and place a pig-tail catheter for angiography above the TEVAR through the other. [DS1] [HA2]
-place a 7 fr sheath in either jugular down to the RA to be able to obtain central venous gases (and labs).
-place a 7 fr sheath in the other carotid or either brachial artery, and through this place an aortic pressure probe (which will remain proximal to the TEVAR graft)
-place a 7 fr sheath in the right or left jugular for central venous pressure probe
-place an at least 7 fr sheath in left femoral vein through which we will hemorrhage and later resuscitate[HA3] [DS4] .
-place a 10 fr sheath in right femoral artery for TEVAR deployment later[DS5]
-also place EKG leads, oxygen saturation probe, rectal temperature probe and a bovie pad (after shaving).
7. Perform a lower abdominal laparotomy for cystostomy (place a foley catheter into the bladder) to facilitate bladder drainage.
8. Perform a left anterolateral thoracotomy. Place the 3 or 4mm flow probe around the coronary flow probe and add ultrasound jelly to the probe.
10. Perform a TIMEOUT. Confirm all line placements, confirm all sheaths work (drawback and flush), confirm fluids are ready, that the timer is ready and reset, that data is being transduced through LabChart through appropriately labeled channels and saved. Confirm ventilatory settings.
11. Confirm fluoroscopically that all catheters and devices are appropriately positioned.
12. Heparinize the animal with 10k units of heparin[HA6] [DS7]
II. Baseline normalization period: (60 min)
1. Start mIVF of 0.9% NS and give 50ccs of D50.
2. Obtain VBG, ABG, Trop, Chem8, and 5 tubes of serum at start of baseline period.
3. Get baseline blood resistivity, enter value into the PV catheter system control.
Throughout baseline, stent and observation periods use the following guidelines for physiologic control of the animal:
- Treat glucose < 65 with 1 amp D50
- for pH < 7.2 give on ampule of bicarbonate
- treat pCO2 as necessary with MV changes
- during resuscitation, treat sustained MAP < 65 after starting fluids with pressor, first line is norepinephrine.
III. Perform TEVAR
1. Confirm access with pigtail in aorta proximal to left subclavian, and that all lines and ports flush.
2. Place Amplatz wire into ascending aorta from femoral artery access.
3. Reposition C arm (right posterior oblique position to splay arch) if needed and confirm placement of wires and devices (Nation et. al).
4. Place stent and deployment system over the Amplatz into the aorta just proximal to the left subclavian.
5. In rapid sequence:
a. Induce respiratory arrest
b. Deploy device
c. Resume respirations
6. Remove deployment device, replace with balloon.
7. Balloon TEVAR stent (there is no dissection in this model).
8. Angiogram to confirm placement and rule out endoleak[DS8] .
IV. Monitor the animal (180 mins)
1. Obtain a VBG and ABG at the start of this period, then every hour and at the end of this period.
2. Confirm ventilatory stability with each set of labs.
3. Ends with chem8, VBG, ABG, and troponin. Obtain full thickness heart tissue and place in formalin. Obtain 5 tubes of blood, spin down and pipet off serum; place serum in -5 deg C freezer.
[DS1]an entire second paper here could done be: test for endoleaks using various imaging mechanisms once in post op monitoring phase. Since we will be in this phase for so long we can image the TEVAR stent several ways and see which is best (IA vs IV, on table CT vs DSA, etc) and this will not even increase the length of study for each pig.