Intraoperacijski TEE i anesteziološko liječenje bolesnika s mehaničkom potporom srca

A ventricular assist device (VAD) is inserted to provide mechanical circulatory support. A VAD can rest the myocardium and allow it to recover from stunning or hibernation, while maintaining vital organ perfusion (bridge-to-recovery). If myocardial recovery cannot occur, the goal is to support the patient to transplantation (bridge-to-transplantation), or, if the patient is not a transplant candidate, to enhance the quality of life for a limited period of time (destination therapy). Perioperative transesophageal echocardiography is a major component of patient management, and it is important for surgical and anesthetic decision-making. In addition to the standard examination, device-specific pre-, intra-, and postoperative considerations are essential to the echocardiographic evaluation. These include: (a) the pre-VAD insertion examination of the heart and large vessels, in order to exclude significant aortic regurgitation, tricuspid regurgitation, mitral stenosis, patent foramen ovale or other cardiac abnormality that could lead to right-to-left shunt after the left VAD placement, intracardiac thrombi, ventricular scars, pulmonic regurgitation, pulmonary hypertension, pulmonary embolism and atherosclerotic disease in the ascending aorta; and to assess the right ventricular function; and (b) the post-VAD insertion examination of the device and reassessment of the heart and large vessels. The examination of the device aims to confirm the completeness of the device and heart deairing, cannulas alignment and patency, and the competency of the device valves using two-dimensional, and color, continuous and pulsed wave Doppler modalities. The goal of the heart examination after the implantation should be to exclude the aortic regurgitation or an uncovered rightto- left shunt, and to assess the right ventricular function, the left ventricular unloading, and the effect of the device settings on the global heart function.Uređaj za mehaničku potporu srcu (eng. VAD) se ugrađuje radi pružanja mehaničke potpore srcu i cirkulaciji. Njime se osigurava oporavak miokarda nakon stunninga i hibernacije, i u isto vrijeme održava perfuzija vitalnih organa (eng. bridge-to-recovery). Ukoliko se miokard ne može oporaviti od oštećenja tada je cilj ovakve terapije pružiti potporu bolesniku do trenutka transplantacije srca (eng. bridge-to-transplantation), ili ukoliko bolesnik nije pogodan za transplantaciju, poboljšati mu kvalitetu života u ograničenom vremenu (ciljna terapija). Perioperacijski TEE je glavna metoda u liječenju i nadziranju takvih bolesnika koja pruža brojne informacije i kirurgu i anesteziologu, olakšavajući pri tom donošenje važnih terapijskih odluka. Uz osnovni standardni pregled, za ehokardiografsku procjenu su važni i za uređaj specifični pre-, intra- i postoperacijski ehokardiografski pregled. To uključuje: (a) pregled srca i velikih krvnih žila prije postavljanja VAD uređaja, kako bi se isključila značajnija aortna regurgitacija, trikuspidna regurgitacija, mitralna stenoza, otvoreni foramen ovale i druge abnormalnosti koje bi mogle dovesti do D-L shunt-a nakon postavljanja VAD-a, stvaranja intrakardijalnih tromba, ventrikulskih ožiljaka, plućne regurgitacije i hipertenzije, plućne embolije i aterosklerotske bolesti u uzlaznoj aorti. Važno je i procijeniti funkciju desnog ventrikula, i (b) pregled uređaja nakon postavljanja VAD-a i ponovna procjena srca i velikih krvnih žila. Cilj pregleda uređaja je potvrditi ispravnost uređaja, izvršenog srčanog odzračivanja; potvrditi ispravan položaj kanila i njihovu prohodnost, kompetentnost valvula i to uporabom dvodimenzionalnog, obojenog, kontinuiranog i pulsnog doplera. Cilj pregleda srca nakon implantacije je isključiti aortnu regurgitaciju ili neprepoznati D-L shunt, i procijeniti funkciju desnog ventrikla, odterećenost lijevog ventrikla i općenito učinak različitih podešavanja uređaja na globalnu srčanu funkciju

Intraoperacijski TEE i anesteziološko liječenje bolesnika s mehaničkom potporom srca

A ventricular assist device (VAD) is inserted to provide mechanical circulatory support. A VAD can rest the myocardium and allow it to recover from stunning or hibernation, while maintaining vital organ perfusion (bridge-to-recovery). If myocardial recovery cannot occur, the goal is to support the patient to transplantation (bridge-to-transplantation), or, if the patient is not a transplant candidate, to enhance the quality of life for a limited period of time (destination therapy). Perioperative transesophageal echocardiography is a major component of patient management, and it is important for surgical and anesthetic decision-making. In addition to the standard examination, device-specific pre-, intra-, and postoperative considerations are essential to the echocardiographic evaluation. These include: (a) the pre-VAD insertion examination of the heart and large vessels, in order to exclude significant aortic regurgitation, tricuspid regurgitation, mitral stenosis, patent foramen ovale or other cardiac abnormality that could lead to right-to-left shunt after the left VAD placement, intracardiac thrombi, ventricular scars, pulmonic regurgitation, pulmonary hypertension, pulmonary embolism and atherosclerotic disease in the ascending aorta; and to assess the right ventricular function; and (b) the post-VAD insertion examination of the device and reassessment of the heart and large vessels. The examination of the device aims to confirm the completeness of the device and heart deairing, cannulas alignment and patency, and the competency of the device valves using two-dimensional, and color, continuous and pulsed wave Doppler modalities. The goal of the heart examination after the implantation should be to exclude the aortic regurgitation or an uncovered rightto- left shunt, and to assess the right ventricular function, the left ventricular unloading, and the effect of the device settings on the global heart function.Uređaj za mehaničku potporu srcu (eng. VAD) se ugrađuje radi pružanja mehaničke potpore srcu i cirkulaciji. Njime se osigurava oporavak miokarda nakon stunninga i hibernacije, i u isto vrijeme održava perfuzija vitalnih organa (eng. bridge-to-recovery). Ukoliko se miokard ne može oporaviti od oštećenja tada je cilj ovakve terapije pružiti potporu bolesniku do trenutka transplantacije srca (eng. bridge-to-transplantation), ili ukoliko bolesnik nije pogodan za transplantaciju, poboljšati mu kvalitetu života u ograničenom vremenu (ciljna terapija). Perioperacijski TEE je glavna metoda u liječenju i nadziranju takvih bolesnika koja pruža brojne informacije i kirurgu i anesteziologu, olakšavajući pri tom donošenje važnih terapijskih odluka. Uz osnovni standardni pregled, za ehokardiografsku procjenu su važni i za uređaj specifični pre-, intra- i postoperacijski ehokardiografski pregled. To uključuje: (a) pregled srca i velikih krvnih žila prije postavljanja VAD uređaja, kako bi se isključila značajnija aortna regurgitacija, trikuspidna regurgitacija, mitralna stenoza, otvoreni foramen ovale i druge abnormalnosti koje bi mogle dovesti do D-L shunt-a nakon postavljanja VAD-a, stvaranja intrakardijalnih tromba, ventrikulskih ožiljaka, plućne regurgitacije i hipertenzije, plućne embolije i aterosklerotske bolesti u uzlaznoj aorti. Važno je i procijeniti funkciju desnog ventrikula, i (b) pregled uređaja nakon postavljanja VAD-a i ponovna procjena srca i velikih krvnih žila. Cilj pregleda uređaja je potvrditi ispravnost uređaja, izvršenog srčanog odzračivanja; potvrditi ispravan položaj kanila i njihovu prohodnost, kompetentnost valvula i to uporabom dvodimenzionalnog, obojenog, kontinuiranog i pulsnog doplera. Cilj pregleda srca nakon implantacije je isključiti aortnu regurgitaciju ili neprepoznati D-L shunt, i procijeniti funkciju desnog ventrikla, odterećenost lijevog ventrikla i općenito učinak različitih podešavanja uređaja na globalnu srčanu funkciju

Kardioprotektivni učinak sevoflurana s obzirom na vrijeme primjene pri operacijama aortokoronarnoga premoštavanja [Cardioprotective effect of sevoflurane with regard to time of application in patients undergoing coronary artery bypass grafting]

Background: Sevoflurane is a volatile anaesthetic which belongs to the group of general anaesthetics. Its cardioprotective effect has been proved in experimental and clinical studies. However, it still hasn't been studied whether this effect on the myocardium differs depending on the time of the administration. The aim of this study was to determine whether the cardioprotective effect of sevoflurane was more expressed when administered before the onset of myocardial ischaemia (during preconditioning phase of coronary bypass grafting operations) compared to its administration after the period of ischaemia (during postconditioning). Methods: Seventy-two patients scheduled for elective coronary artery bypass graft surgery were randomly assigned to one of three groups: a group of patients who were anaesthetised by sevoflurane administered before the onset of ischaemia (SEVO pre; n=24), a group of patients who were anaesthetised by sevoflurane administered after the ischaemic period (SEVO post; n=24) and a control group who were anaesthetised only by midazolam and fentanyl (Control; n=24). The effect on myocardium was assessed by successive measurements of cardiac biomarkers in the perioperative period: troponin I (cTnI), creatine kinase (CK), CK-MB isoenzyme and lactate dehydrogenase (LD). The degree of myocardial injury was estimated quantitatively on the basis of the summary values of the cardiac biomarkers and categorically on the basis of the distribution of peak troponin I concentrations in the perioperative period. The following summary variables were: peak value, time to reach the peak value, difference between the peak and the first measured value, percent difference between the peak and the first measured value, difference between the last and the first measured values, percent difference between the last and the first measured values, the area under the curve of the measured values through the period. The categorical assessment of periprocedural myocardial injury was done on the basis of peak troponin I at 2, 4, 8 and 12 μg/L. Results: Quantitatively the estimated degree of perioperative myocardial injury did not differ significantly between the groups for any of the monitored parameters. The only difference found was a significantly lower value of CK-MB difference between the peak and the first measured value in the group SEVO pre in comparison to the SEVO post group (p = 0.010). This may speak in favour of smaller periprocedural myocardial injury in the SEVO pre group. Based on peak troponin I concentrations, the number of patients who had perioperative myocardial injury did not differ significantly between the groups, although there was a trend of the smallest number of such patients in the SEVO pre group for all monitored peak concentrations of troponin I. In a univariate analysis of predictor variables for the development of periprocedural myocardial injury (peak troponin I > 2 μg/L), lower body surface area (p = 0.010) was found the only significant variable. In a multivariate analysis model for the same outcome, in which the body surface area and administration mode of anaesthetic were included, the body surface area (OR = 0.020; 95% CI = 0.001 − 0.401, p = 0.011), and SEVO pre group compared to SEVO post group (OR = 0.277; 95% CI = 0.078 − 0.977, p = 0.046) were found as significant favourable predictors. Within patients that were operated in CABG method and also within those operated in OPCAB method, the quantitatively and categoricaly estimated degree of perioperative myocardial injury, did not differ significantly between the groups for any of the monitored parameters. Conclusion: This research did not unequivocally establish the cardioprotective effect of sevoflurane when administered before the onset of ischaemia compared to midazolam and fentanyl, nor did it establish the cardioprotective effect when compared to sevoflurane administered after the ischaemic period. Some of our results may suggest possible cardioprotective effect of sevoflurane when administered before ischaemia compared to sevoflurane administered after ischaemia in terms of a minor periprocedural myocardial injury. However, further randomized controlled trials are necessary to confirm this result