[The mechanism producing nausea during ventriculography performed with ioxaglate: the implications of a randomized study].
BACKGROUND
The mechanism of ioxaglate-induced nausea has not been fully elucidated. Recent studies have demonstrated that serotonin is one of the principal neurotransmitters of emesis in humans. On the other hand, the greater capacity of ioxaglate to stimulate vomiting has been ascribed to its great ability to inhibit cholinesterase.


METHODS
To determine if oral metoclopramide (a serotonin receptor-blocker) is effective in the prophylaxis of ioxaglate-induced nausea during left ventriculography, 637 of 711 consecutive eligible patients were included in a prospective study. Patients were randomized to receive, 60-90 minutes before the procedure, either diazepam 10 mg p.o. (control group [n = 315]) or diazepam 10 mg p.o. plus metoclopramide 10 mg p.o. (metoclopramide group [n = 322]).


RESULTS
The two randomized groups were similar in relation to baseline clinical and hemodynamic characteristics. Nausea was documented in 103 patients (16.1%) with similar incidence in the two groups (control group: 16.8%, metoclopramide group: 15.5%; p = NS). Nausea duration was also similar (56 +/- 63 s vs 52 +/- 63 s; p = NS). When patients with and without nausea were compared, the following variables showed a significant difference between the two groups: male gender (86% vs 76%; p < 0.05), age (53 +/- 10 yrs vs 56 +/- 9 yrs; p < 0.05) and body surface area (1.84 +/- 0.2 m2 vs 1.78 +/- 0.1 m2; p < 0.01). Stepwise multiple regression analysis identified low age (p = 0.02) and male gender (p = 0.06) as independent predictors of nausea. The incidence of nausea was 24% in males < or = 45 yrs vs 9% in females > 45 yrs (p < 0.05).


CONCLUSIONS
Prophylaxis with oral metoclopramide did not reduce the incidence of ioxaglate-induced nausea during left ventriculography. This data do not support a role of serotonin in the production of nausea by ioxaglate. Low age an male gender are independent predictors of nausea apparition during left ventriculography. A cholinergic mechanism is probably involved in the capacity of ioxaglate to stimulate vomiting.
Gómez-Hospital
J A
JA
Unidad de Hemodinámica y Cardiología Intervencionista, Universidad de Barcelona, L'Hospitalet de Llobregat.
Cequier
A
A
Sala
J
J
Mauri
J
J
Catarino
C
C
Sabaté
M
M
Barthe
J E
JE
Valerio
L
L
Jara
F
F
Esplugas
E
E
D000284:Administration, Oral; D003975:Diazepam / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D015637:Gated Blood-Pool Imaging; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007485:Ioxaglic Acid / Q000009:adverse effects*; D008297:Male; D008787:Metoclopramide / Q000627:therapeutic use; D008875:Middle Aged; D009325:Nausea / Q000139:chemically induced* / Q000517:prevention & control
D008787:Metoclopramide; D003975:Diazepam; D007485:Ioxaglic Acid
Mecanismo de producción de las náuseas duŕante la ventriculografía realizada con ioxaglato: implicaciones de un estudio randomizado.