Valsalva Maneuver

Q: Patient is in Supraventricular tachycardia (SVT). For the sake of discussion - name few vagal maneuvers (activation of the parasympathetic nervous system)?

Answer:

• The Valsalva maneuver *1.
• Just holding one's breath for a few seconds,
• Coughing,
• Putting towel of ice cold water on face(diving reflex)*2
• Drinking a glass of ice cold water,
• Standing on one's head!
• Carotid sinus massage *3
• Act of defecation or rectal massage
• Act of urination

*1 The Valsalva maneuver works by increasing intra-thoracic pressure and affecting baro-receptors (pressure sensors) within the arch of the aorta.

*2 Diving reflex is triggered specifically by cold water contacting the face - less than 21 °C (70 °F). Submersion of body parts other than the face does not cause diving reflex. It cause bradycardia and peripheral vasoconstriction.

*3 Carotid sinus massage is often not recommended due to risks of stroke in those with plaque in the carotid arteries.

#hemodynamics

#cardiology

References:

1. Pstras L, Thomaseth K, Waniewski J, Balzani I, Bellavere F. The Valsalva manoeuvre: physiology and clinical examples. Acta Physiol (Oxf). 2016 Jun;217(2):103-19. doi: 10.1111/apha.12639. Epub 2016 Jan 5. PMID: 26662857.

2. Looga R. The Valsalva manoeuvre--cardiovascular effects and performance technique: a critical review. Respir Physiol Neurobiol. 2005 May 12;147(1):39-49. doi: 10.1016/j.resp.2005.01.003. PMID: 15848122.

3. Srivastav S, Jamil RT, Zeltser R. Valsalva Maneuver. [Updated 2023 Aug 21]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537248/