Nicoladoni–Branham sign: Difference between revisions
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== Mechanism == |
== Mechanism == |
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In AV |
In an AV fistula there is [[Shunt (medical)|shunting]] of blood from the arteries directly into a vein, bypassing the capillary beds. This causes a fall in [[Vascular resistance|peripheral vascular resistance]]. Because blood pressure is directly proportional to peripheral vascular resistance, in an AV fistula there is a fall in blood pressure and subsequent [[Tachycardia|reflex tachycardia]]. |
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When the artery proximal to the fistula is compressed, blood is no longer shunted and the peripheral vascular resistance is increased suddenly. This causes relative hypertension within 1 or 2 heartbeats.<ref name=":1">{{Cite journal |last1=Wattanasirichaigoon |first1=Somkiat |last2=Pomposelli |first2=Frank B. |date=1997-07-01 |title=Branham's sign is an exaggerated Bezold-Jarisch reflex of arteriovenous fistula |url=https://www.jvascsurg.org/article/S0741-5214(97)70168-X/abstract |journal=Journal of Vascular Surgery |language=English |volume=26 |issue=1 |pages=171–172 |doi=10.1016/S0741-5214(97)70168-X |pmid=9240342 |issn=0741-5214}}</ref> Bradycardia soon follows due to the activation of the [[baroreceptor]]s in the |
When the artery proximal to the fistula is compressed, blood is no longer shunted and the peripheral vascular resistance is increased suddenly. This causes relative hypertension within 1 or 2 heartbeats.<ref name=":1">{{Cite journal |last1=Wattanasirichaigoon |first1=Somkiat |last2=Pomposelli |first2=Frank B. |date=1997-07-01 |title=Branham's sign is an exaggerated Bezold-Jarisch reflex of arteriovenous fistula |url=https://www.jvascsurg.org/article/S0741-5214(97)70168-X/abstract |journal=Journal of Vascular Surgery |language=English |volume=26 |issue=1 |pages=171–172 |doi=10.1016/S0741-5214(97)70168-X |pmid=9240342 |issn=0741-5214}}</ref> Bradycardia soon follows due to the activation of the [[baroreceptor]]s in the left ventricle (the [[Bezold–Jarisch reflex|Bezold-Jarisch reflex]]<ref name=":1" />) |
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Locally |
Locally, because no blood is being shunted, the swelling reduces and bruit/thrill disappears. |
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== Clinical significance == |
== Clinical significance == |
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Revision as of 03:40, 19 June 2022
The Nicoladoni–Branham sign (also called the Branham's sign, the Nicoladoni sign or the Nicoladoni-Israel-Branham sign[1]) is named after Carl Nicoladoni[1] who first noticed the phenomenon of slowing down of pulse in a patient with right arm phlebarteriectasia[1] when brachialis artery was compressed. In modern medicine the sign is elicited when pressure is applied to artery proximal to an arteriovenous fistula and said to be positive if the following occurs :-
- Swelling reduces in size
- Bruit and thrill disappears
- Blood pressure rises
- Pulse rate and heart rate return to normal.[2][3][4]
Mechanism
In an AV fistula there is shunting of blood from the arteries directly into a vein, bypassing the capillary beds. This causes a fall in peripheral vascular resistance. Because blood pressure is directly proportional to peripheral vascular resistance, in an AV fistula there is a fall in blood pressure and subsequent reflex tachycardia.
When the artery proximal to the fistula is compressed, blood is no longer shunted and the peripheral vascular resistance is increased suddenly. This causes relative hypertension within 1 or 2 heartbeats.[5] Bradycardia soon follows due to the activation of the baroreceptors in the left ventricle (the Bezold-Jarisch reflex[5])
Locally, because no blood is being shunted, the swelling reduces and bruit/thrill disappears.
Clinical significance
It helps differentiate the cause of chest pain between High output cardiac failure (AV-shunting) and cardiac (organic) causes in ESRD patients on Hemodialysis with AV-fistula.[6] Where the formal will improve while eliciting the sign and latter would not.
References
- ^ a b c Cadogan, Mike; Miers, James (2021-08-28). "Branham sign". Life in the Fast Lane • LITFL. Retrieved 2022-04-11.
- ^ Branham's sign. The Free Dictionary. URL: http://medical-dictionary.thefreedictionary.com/Branham's+sign. Accessed on: September 28, 2008.
- ^ synd/2995 at Who Named It?
- ^ Velez-Roa S, Neubauer J, Wissing M, et al. (June 2004). "Acute arterio-venous fistula occlusion decreases sympathetic activity and improves baroreflex control in kidney transplanted patients". Nephrol. Dial. Transplant. 19 (6): 1606–12. doi:10.1093/ndt/gfh124. PMID 15034165.
- ^ a b Wattanasirichaigoon, Somkiat; Pomposelli, Frank B. (1997-07-01). "Branham's sign is an exaggerated Bezold-Jarisch reflex of arteriovenous fistula". Journal of Vascular Surgery. 26 (1): 171–172. doi:10.1016/S0741-5214(97)70168-X. ISSN 0741-5214. PMID 9240342.
- ^ Ehtisham, Muhammad; Morales, Alexander; Khudayar, Humnah; Minami, Akiko; Kukhon, Faeq; Minami, Taro (2017-10-01). "Nicoladoni Branham Sign: A Simple Bedside Maneuver to Reveal a Complex Hemodynamic Problem in Patients on Hemodialysis". Chest. 152 (4): 742–750. doi:10.1016/j.chest.2017.08.772. ISSN 0012-3692. PMID 28300571.