From Ing, F. Stenting branch pulmonary arteries p.100 in Complications during percutaneous interventions for congenital and structural heart disease. Ed. Hijazi, Z. et al. Informa health care, London, UK. 2008)
There is really no need for such terms as "caudo-cranial" and "cranio-caudal". But, these terms appears in textbooks (esp. the old ones). So, we need to cope with them. Here is an explanation...from one of the books. Does not necessarily mean that this is what is meant in a different text book!!!
From p.286 The Cardiac Catheterization Handbook. 3rd Ed. Edited by Morton J. Kern. Mosby, St Louis 1999)
Case reportInternal Right Ventricular Band for Multiple Ventricular Septal Defects in a Neonate Undergoing Arterial Switch and Aortic Arch Repair
William W. Carroll, Girish S. Shirali and Scott M. Bradley
A neonate presented with d-transposition of the great arteries, aortic arch hypoplasia, aortic coarctation, and multiple ventricular septal defects. During the arterial switch procedure and the aortic arch repair, a fenestrated Gore-Tex disk (W.L. Gore & Assoc, Flagstaff, AZ) was sewn into the right ventricular outflow tract to restrict pulmonary blood flow. The internal right ventricular band successfully controlled the pulmonary blood flow, maintaining a systemic oxygen saturation of 88% to 92%, and allowing growth from 3.5 to 10.5 kg. At 8 months of age, the internal band in the patient was removed, and the ventricular septal defects were successfully closed.k
Images from Radiology of Congenital Heart Disease by Kurt Amplatz & James H. Moller. Mosby Year Book, St. Louis, MO. 1993. p.386-87. Appearance & Location of inlet VSD in LAO view angiogram. Notice the distance from aortic valve to crest of ventricular septum (black arrow)
British Journal of Surgery 1953;40(164):616-21. A.T.Andreasen & F.Watson
This paper and the one before this paper, from the same group showed that the dogs survived when both SVC and IVC were clamped with only azygos flow allowed to go into right atrium. After the experiment, all surviving dogs behaved "normally".
Later, Lillehei's group in Minnesota showed that the amount of flow via Azygos vein was 10% of the venous return. This formed the basis for cross-circulation surgeries performed using another human being as the cardiopulmonary support - prior to availability of cardio-pulmonary bypass machine.
Donor is cannulated in the groin. The blood from the donor goes through a pump that is set to pump a calculated volume (equivalent to the azygos factor) to the recipient. Open heart surgery was performed with this set up in 1953-54.
Then, check Antifactor Xa level and adjust to set maintenance dose:
< 0.35 U/ml → Increase by 20% - Check dose 4 hr after next dose
0.35-0.49 U/ml → Increase by 10% - Check dose 4 hr after next dose
0.5 - 1.0 U/ml → No change - Check level next day, 1 week later and monthly
1.1 - 1.5 U/ml → Decrease by 20% - Check level before next dose
1.6 - 2.0 U/ml → Hold dose for 3 hrs and Decrease by 30% - Check level before next dose and 4 hr after
? 2.0 U/ml → Hold doses until level is 0.5 U/ml, Resume with decreased dose by 40% - Check every 12 hrs until level < 0.5 U/ml. Then, before next dose.
From Lexi-Comp To maintain INR 2-3: Loading: Day 1: 0.2 mg/kg/day (0.1 mg/kg/day if liver dysfunction is present) Day 2-4: Depends on daily INR 1.1 - 1.3 → Repeat same dose 1.4 - 3.0 → 50% of loading dose 3.1 - 3.5 → 25% of loading dose > 3.5 → Hold until INR < 3.5. Then, start 50% of loading dose.
Maintenance (Day 5 & beyond): Depends on INR 1.1 -1.4 → Increase 20% 1.5 - 1.9 → Increase 10% 2-3 → No change 3.1 - 3.5 → Decrease 10% > 3.5 → Hold until INR < 3.5. Then, start 20% lower than prior dose