Procedures such as the knee-chest position which increases aortic wave reflection, increasing pressure on the left side of the heart, decreasing the right-to-left shunt thus decreasing the amount of deoxygenated blood entering the systemic circulation.
Oxygen is ineffective in treating hypoxic spells as the underlying problem is lack of blood flow through the pulmonary circuit and not alveolar oxygenation.
In case all these measures fail, an emergency Blalock-Taussig shunt might be needed.
↑Murakami T (2002). "Squatting: the hemodynamic change is induced by enhanced aortic wave reflection". Am. J. Hypertens. 15 (11): 986–8. PMID12441219.
↑Abe K, Shimada Y, Takezawa J, Oka N, Yoshiya I (March 1982). "Long-term administration of prostaglandin E1: report of two cases with tetralogy of Fallot and esophageal atresia". Crit. Care Med. 10 (3): 155–8. doi:10.1097/00003246-198203000-00003. PMID7199417.
↑Tsze DS, Vitberg YM, Berezow J, Starc TJ, Dayan PS (July 2014). "Treatment of tetralogy of Fallot hypoxic spell with intranasal fentanyl". Pediatrics. 134 (1): e266–9. doi:10.1542/peds.2013-3183. PMID24936003.