Eating a dried salted plum during compression reduced the incidence of moderate to severe ear pain during compression

Clinical bottom line:

1. The proportion of patients complaining of moderate to severe ear pain was reduced when compressed while eating a dried salted plum.

2. There was no reduction in otoscopic assessment of the severity of middle ear barotrauma

Citation/s:1. Meng FC, Shen CH, Wu D, Chu CM, Shih CP, Lin HC, Peng CK, Chang SC, Huang KL. Dried salted plum consumption ameliorates hyperbaric oxygen therapy-induced otalgia severity at the first chamber session: a prospective randomized controlled study. Undersea & hyperbaric medicine: journal of the Undersea and Hyperbaric Medical Society, Inc. 2017;44(6):551-7.

Lead author's name and fax:Chih-Hao Shen, MD –

Three-part Clinical Question:During an initial compression for hyperbaric oxygen delivery, does eating a dried salted plum versus doing nothing specific result in any reduction in otalgia from middle ear barotrauma?

Search Terms:Middle ear barotrauma; prevention; Valsalva

The Study:Non-blinded randomised controlled trial with intention-to-treat.

The Study Patients:Adult patients undergoing their first compression for the purpose of delivering hyperbaric oxygen therapy

Control group(N = 37; 37 analysed): Patients underwent a 15 minute compression from 1 ATA to 2.5 ATA after instructions on clearing ears.

Experimental group(N = 53; 53 analysed): As above but patients were also asked to eat a dried salted plum during compression

The Evidence:


Time to Outcome

Control Group

Plum Group

Relative risk reduction

Absolute risk reduction


Otoscopic signs of severe (Grade 3 to 4) MEB (Teed score 0 to 5 worst)

30 mins






95% CIs:

-87% to 87%

-0.16 to 0.16

NNT 6 to INF;
NNH 6 to INF

Moderate to severe otalgia, VAS >3 (VAS 0 to 10 worst)

30 mins






95% CIs:


0.01 to 0.21

5 to 125


1. Not a surprising finding as the consumption of saliva-inducing food during compression has a long and venerable history of assisting ear clearing.

2. It is not quite clear what accounts for the difference in the number of patients allocated to each arm.

3. There seemed no close relationship between the Teed score and the degree of otalgia.

Appraised by:Mike Bennett; Monday, 21 January 2019 Email:

Kill or Update By: June 2022