Chest pain (non-cardiac): the results of edrophonium provocative testing may be influenced by the tester.

Clinical bottom line (level 1b-)

  1. There were wide differences in patients reporting chest pain during edrophonium testing depending on the clinician performing the test.
  2. These differences may be due to the manner of the clinician.
Rose et al: American Journal of Gastroenterology 1993; 88 (1): 20-24
Expires Unknown Month 2001

The study

Double-blinded concealed randomised trial with intention-to-treat
Setting: clinical manometric lab, university hospital, USA

62 patients (aged mean 51 years, 50% male) with non-cardiac chest pain and negative coronary angiograms and stress testing

Excluded if
  • on medication
  • lack of proper cardiac evaluation
  • chest pain at time of testing


    • Control Group: (n = 29, 29 analysed): told 'You will receive different medications to determine if any changes occur in the tracing'. Following 10 mg of edrophonium iv, patient had 10 x 5 ml swallows. If no pain reported 10 min after last injection, patient was asked ' Have you felt any effect from the injections?'
    Experimental Group: (n = 33, 33 analysed): told 'We are going to give a medication to see if we can reproduce the pain that you usually have in your chest.' Given 1 ml 0.9% saline, and asked 'Do you have any pain?' Following 10 mg of edrophonium iv, patient had 10 x 5 ml swallows. If no pain reported 10 min after last injection, patient was asked ' Do you have any pain?'
    Patients were questioned by a nurse using a neutral tone.
    100% followed for ?

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    chest pain unknown 2
    (6.90%)    		 7
    (21.2%)    		 -208%
    (-1265% to 31%)    		 -14.3%
    (-31.0% to 2.41%)    		 -7
    (NNT = 42 to infinity;
    NNH = 3 to infinity)

  • Outcomes were assessed by a blinded interpreter.
  • No significant differences noted in amplitude or duration of oesophageal contractions before or after edrophonium in patients with or without chest pain.
  • In a retrospective survey of 260 patients (36% male; aged mean ~ 49) seen in the previous 2 years showed significant differences in the number of patients who reported chest pain depending on the physician performing the test.
    • physician A: patients with chest pain during test- 32/103: 31% (22% to 40%)
    • physician B: chest pain- 21/104: 20% (13% to 28%)
    • physician C: chest pain- 5/53: 9.4% (1.6% to 17%)

    • Comments

    1. Other studies have reported huge differences in the number of patients reporting pain: probably dependent on selection-bias.

    Citation

    1. Rose S, Achkur E, Falk GW, et al: interaction between patient and test administrator may influence the results of edrophonium provocative testing in patients with noncardiac chest pain.. American Journal of Gastroenterology 1993; 88 (1): 20-24
    Search Terms: chest pain in Cochrane
    Contributor: Chris Ball and Clare Wotton, Unknown Month 2000
    Reviewer:

    Clinical Question.
    Patient non-cardiac chest pain
    Intervention or Exposure edrophonium testing
    Outcome chest pain