ABSTRACT
In order to evaluate the hemodynamic management during escharectomy and grafting in severely burned patients, 1.978 (1.635-2.201) intraoperative records of 56 patients were reviewed. Mean age was 39 years (21-59). Mean burned surface area was 32% (11-75). All patients had a multiorganic failure syndrome (MOF). During the procedure, all vaso and cardioactive drugs infusions were maintained (epinephrine, norepinephrine, dopamine either alone or in combination). The aim of therapy was to maintain a normal mean arterial pressure (MAP), modifying the dosages of vasoactive drugs and/or volume replacement according to the results. Hemodynamic monitoring was performed with an intraoesophagic Eco Doppler device, measuring aortic output (AO) and integrating the values of MAP and ECG for the calculation of the systemic vascular resistances (TSVR) and the systolic time intervals (STI) as estimation of myocardial performance. The results, compared with normal values showed: maintained tachycardia, MAP of 94 ± 22 mmHg, increased AO and diminished TSVR. The STI showed values of myocardial depression in spite of the inotropic infusions: PePi 148±26 mseg (p<0,05), PePi/LVETi 0,40±0,1 (p<0,05) The comparison of the cases between those with MAP > 90 mm Hg and those with MAP <90 mmHg, showed higher TSVR and values suggestive of myocardial depression in the former ones. MAP>90 mmHg :TSVR 1232±568 dyn.s-1.cm-5.m-2, PePi/LVETi 0,42±0,1. MAP<90 mmHg TSVR 802±389, PePi/LVETi 0,39±0,1 (p<0,05 for both). The measured hemodynamic pattern matches with an hyperdinamic one, with a sustained beta stimulus and diminished TSVR, although enough to maintain a normal MAP. In spite of the infusion of vaso and cardioactive drugs and the fall of the TSVR, myocardial depression was almost constantly detected. This one increased when the postcharge raised, even though TSVR were in lower values than the normal mean. This intraanesthetic hemodynamic management, trying to modulate the TSVR the minimun necessary to obtain a MAP within normal limits, seems to be acceptable for this special group of sick patients.