ORIGINAL ARTICLES  ANESTHESIOLOGY Free

Minerva Anestesiologica 1998 July-August;64(7-8):321-8

Copyright © 1998 EDIZIONI MINERVA MEDICA

language: English

Comparison of intravenous nifedipine and sodium nitroprusside for treatment of acute hypertension after cardiac surgery

Bertolissi M., De Monte A., Giordano F.

Azienda Ospedaliera S. Maria della Misericordia - Udine, Second Department of Anesthesia and Intensive Care Medicine

Back­ground. The ­present ­study was ­designed to com­pare the hemo­dy­namic ­effects of nifed­i­pine and ­sodium nitro­prus­side, intra­ve­nously admin­is­tered to con­trol ­acute ­syste-mic hyper­ten­sion in the imme­diate post­op­er­a­tive ­period ­after ­open ­heart sur­gery.
­Methods. The ­study was car­ried out on 16 ­patients who devel­oped ­acute ­systemic hyper­ten­sion, ­defined as ­mean ­systemic arte­rial pres­sure (MAP) ­values ­above 90 ­mmHg, ­within the ­first ­hour ­after ICU admis­sion, ­which fol­lowed car­diac sur­gery for val­vular and cor­o­nary dis­ease. ­After con­trol meas­ure­ments ­during the hyper­ten­sive ­status, ­each ­patient was ­treated by alter­nating infu­sions of ­sodium nitro­prus­side and nifed­i­pine in ­order to ­obtain MAP ­values of ­about 80 ­mmHg ­with ­each admin­is­tra­tion. All ­patients had pre­op­er­a­tive ­left ven­tric­ular ejec­tion frac­tion ­above 45%.
­Results. Nifed­i­pine pro­duced a ­superior and sig­nif­i­cant ­increase in car­diac ­index (CI) (+28%) and ­stroke ­volume ­index (SVI) (+30%), and a ­greater ­decrease in ­systemic vas­cular resis­tance ­index (­SVRI) (-39%), ­when com­pared ­with ­sodium nitro­prus­side [CI (+5%), SVI (no ­change), ­SVRI (-27%)]. On the con­trary the ­right and ­left ven­tric­ular ­filling pres­sures ­were ­reduced sig­nif­i­cantly by ­sodium nitro­prus­side [pul­mo­nary cap­il­lary ­wedge pres­sure (-30%), cen­tral ­venous pres­sure (-20%)], ­while nifed­i­pine ­induced ­small and not sig­nif­i­cant ­changes in the pre­load ­values. No ECG ­changes sug­gesting ­ischemic myo­car­dial ­events ­were ­observed in any ­patient.
Con­clu­sions. On the ­basis of ­these ­results it has ­been con­cluded ­that nifed­i­pine ­affects pri­marily the arter­i­olar resis­tance ves­sels ­without sig­nif­i­cant ­changes in ­venous ­tone, ­which is on the con­trary mark­edly ­reduced by ­sodium nitro­prus­side. The ­better improve­ment in car­diac ­index and ­stroke ­volume ­index ­obtained ­with the admin­is­tra­tion of nifed­i­pine, ­makes ­this ­drug a ­good alter­na­tive to ­sodium nitro­prus­side for treat­ment of ­acute hyper­ten­sion ­after car­diac sur­gery in ­patients ­with a ­good pre­op­er­a­tive ­left ven­tric­ular func­tion.