OPEN IN READ APP
JOURNAL ARTICLE
RANDOMIZED CONTROLLED TRIAL

Identification of the optimum vagal manoeuvre technique for maximising vagal tone

Gavin Smith, Alicia Broek, David McD Taylor, Amee Morgans, Peter Cameron
Emergency Medicine Journal: EMJ 2015, 32 (1): 51-4
24902881

OBJECTIVES: This study sought to determine the most effective technique for Valsalva Manoeuvre (VM) and Human Dive Reflex Manoeuvre (HDR) generation of vagal tone.

METHODS: We conducted a repeated-measures trial of healthy adult volunteers from a university campus, aged 18-56 years, in sinus rhythm. Participants were randomised to VM (in supine or Trendelenberg postures) and HDR (supine or sitting postures) sequentially. Participants performed three trials of each technique, in random order, with a continuous ECG recording. Single-blinded analysis of ECG data was conducted. Mean differences between premanoeuvre and postmanoeuvre R-R intervals and heart rates were calculated for each posture within and between vagal manoeuvres.

RESULTS: Seventy-two participants were enrolled. The difference between VM (supine) and VM (Trendelenberg) was not significant at 0.008 s (-0.023 to 0.038). The difference in mean R-R intervals for HDR (supine) was greater than HDR (sitting) 0.062 (0.031 to 0.093), although this significance was not reflected in a heart-rate change of -0.87 (-3.00 to 1.26). VM supine generated greatest overall mean R-R interval difference, while HDR (sitting) provided the smallest change in R-R interval. The VM (supine) provided a significant maximum effectiveness over the HDR (supine) of 0.102 s (0.071 to 0.132).

CONCLUSIONS: This study demonstrates that VM (supine) generates the greatest vagal tone producing the largest transient heart rate decrease in healthy volunteers. No advantage was identified in Trendelenberg posturing for the VM in this study. These results may assist in the standardisation of vagal manoeuvre technique for the range of therapeutic and diagnostic applications.

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Available on the App Store

Available on the Play Store
Remove bar
Read by QxMD icon Read
24902881
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"