Meral Kanbak

The effect of acute normovolemic hemodilution on homologous blood requirements and total estimated red blood cell volume lost.

Background:Acute normovolemic hernodilution combined with retransfusion is one of the various techniques proposed to avoid homologous blood transfusion in cardiac surgery. The purpose of the present paper is to study the effect of the volume of autologous blood collected pre‐cardiopulmonary bypass (CPB) on homologous blood requirements and total estimated red blood cell (RBC) volume lost in coronary artery bypass grafting (CABG) surgery.

Propofol offers no advantage over isoflurane anesthesia for cerebral protection during cardiopulmonary bypass: a preliminary study of S-100beta protein levels.

PurposeDespite advances in anesthesia, cardiopulmonary bypass (CPB) and surgical techniques, cerebral injury remains a major source of morbidity after cardiac surgery. We compared the effects of two different anesthetic techniques, isoflurane vs propofol on neurological outcome by serum S-100ß protein and neuropsychological tests after coronary artery bypass grafting (CABG).MethodsTwenty patients undergoing CABG, randomly allocated into two groups, were enrolled in this prospective, controlled, preliminary study. Isoflurane was used in group I and propofol in group R Neurological examination and a neuropsychologic test battery consisting of the mini mental state examination (MMSET) and the visual aural digit span test (VADST) were obtained preoperatively and on the third and sixth postoperative days. Blood samples for analysis of S-100ß protein were collected before anesthesia (T1), after heparinization (T2), 15 min into CPB (T3), after CPB (T4) and at the 24th hr postoperatively (T5).ResultsPostoperative neurological examinations of the patients were normal. VADST performance declined significantly on the third day (P < 0.05) in both groups, and there were no significant differences on VADST and MMSET scores between the two groups. In group P S-100ß protein levels increased significantly at T3 and T4 compared to preoperative and isoflurane levels (P < 0.05).ConclusionsDespite reports about the neuroprotective effects of propofol, S-100ß protein levels were significantly elevated in group R Although there was no deterioration in neuropsychological outcome, propofol appeared to offer no advantage over isoflurane for cerebral protection during CPB in this preliminary study of 20 patients.RésuméObjectifMalgré les progrès de l’anesthésie, la circulation extracorporelle (CEC) et les techniques chirurgicales, les lésions cérébrales demeurent une importante source de morbidité postchirurgie cardiaque. Les effets neurologiques comparés de l’isoflurane et du propofol sont présentés par l’analyse des protéines sériques S-100ß et des test neuropsychologiques après un pontage aortocoronarien (PAC).MéthodeNotre étude préliminaire, prospective et contrôlée a porté sur 20 patients, répartis au hasard en deux groupes, qui devaient subir un PAC. L’isoflurane a été utilisé dans le groupe I et le propofol dans le groupe P L’examen neurologique et une batterie de tests neuropsychologiques, comprenant le mini-examen de l’état mental (MMSET pour mini mental state examination) et le test visuel et auditif de mémoire des chiffres (VADST pour visual aural digit span test), ont été réalisés avant l’opération et aux jours trois et six postopératoires. Les échantillons sanguins nécessaires à l’analyse des protéines S-100ß ont été prélevés avant l’anesthésie (T1), après l’héparinisation (T2), 15 min après le début de la CEC (T3), après la CEC (T4) et 24 h après l’opération (T5).RésultatsLes examens neurologiques postopératoires étaient normaux. La performance au VADST a décliné significativement au jour trois (P < 0,05) chez tous les patients. Il n’y a pas eu de différence intergroupe significative des scores de VADST et de MMSET. Dans le groupe P, les niveaux de protéines S-100ß ont augmenté à T3 et T4, comparés aux niveaux préopératoires et aux niveaux observés avec l’isoflurane (P < 0,05).ConclusionMalgré des études rapportant les effets neuroprotecteurs du propofol, les niveaux de protéines S-100ß ont été significativement élevés dans le groupe P de notre étude. Aucune détérioration neuropsychologiques n’a été observée, mais le propofol ne semble pas offrir d’avantage sur l’isoflurane pour la protection cérébrale pendant la CEC.

The treatment of heparin resistance with Antithrombin III in cardiac surgery

PurposeTo report three patients who developed heparin resistance during cardiac surgery which was successfully managed with 1000 U Antithrombin III (AT III).Clinical featuresWe observed heparin resistance prior to cardiopulmonary bypass (CPB) in one patient and during the CPB in two patients. In the first patient who was scheduled for mitral valve replacement, although heparin was administered sequentially up to 500 U · kg−1 prior the CPB, the ACT value was 354 sec. After 1,000 U ATIII were administered the ACT was 395 sec and CPB was initiated. The ACT remained between 496 and 599 sec throughout CPB and a total of 260 mg protamine sulfate was given. In the other two patients following 300 U · kg−1 heparin, the ACT was up to 400 sec and CPB was initiated. During CPB, ACT were decreased 360 sec and 295 sec in patients II and III respectively. Although heparin was added 1,500 U, ACT increased to ≥ 400 sec could not be achieved. In the second patient AT III activity was found 10%. After the administration of 1,000 U ATIII, ATIII activity was found to be 67% 40 min later and ACT were increased up to 400 sec. There was no thrombosis within the extracorporeal circuit, additional heparin was not required, less protamine was administered (≤, 3 mg · kg−1) and no excessive postoperative bleeding was observed in all patients.ConclusionWe recommend that AT III supplementation should be considered to manage heparin resistance prior or during CPB in patients undergoing open heart surgery.RésuméObjectifPrésenter le cas de trois patients qui ont développé une résistance à l’héparine, pendant une intervention cardiaque, traitée avec succès avec 1 000 U d’antithrombine III (AT III).Éléments cliniquesChez l’un des patients, la résistance à l’héparine s’est manifestée avant la circulation extracorporelle (CEC), mais pendant la CEC chez les deux autres patients. Dans le cas du premier patient pour qui le remplacement de la valvule mitrale avait été planifié, le temps de coagulation activée (TCA) a été de 354 s malgré l’administration séquentielle d’héparine, jusqu’à 500 U · kg−1 avant la CEC. Après l’administration de 1 000 U d’AT III, le TCA était de 395 s et la CEC a été amorcée. Le TCA est demeuré entre 496 et 599 s tout au long de la CEC et 260 mg de sulfate de protamine ont été administrés en tout. Chez les deux autres patients, la CEC a été instaurée à la suite de l’administration de 300 U · kg−1 d’héparine alors que le TCA allait jusqu’à 400 s. Pendant la CEC, le TCA est baissé à 360 s et 295 s chez les patients II et III, respectivement. En dépit de 1 500 U d’héparine supplémentaires, le TCA n’a pu être augmenté à 400 s. Chez le deuxième patient, l’activité de l’AT III était de 10 %. L’administration de 1 000 U d’AT III a amené l’activité de l’AT III à 67 %, 40 min plus tard, et les TCA se sont élevés jusqu’à 400 s. Chez tous les patients, il n’y a pas eu de thrombose à l’intérieur du circuit extracorporel, l’héparine supplémentaire n’a pas été nécessaire, l’administration de protamine a été faible (3 mg · kg−1) et il n’y a pas eu de saignements postopératoires excessifs.ConclusionNous recommandons l’administration d’AT III supplémentaire pour traiter la résistance à l’héparine avant, ou pendant la CEC, lors d’interventions à coeur ouvert.

A background infusion of morphine does not enhance postoperative analgesia after cardiac surgery

PurposeTo compare the effects of patient-controlled analgesia (PCA), with or without a background infusion of morphine on postoperative pain relief and stress response after cardiac anesthesia.MethodsWith University Ethics approval, 35 consenting adults undergoing elective open-heart surgery were randomly assigned preoperatively in a double-blind fashion to receive either morphine PCA alone (Group I, n = 15) or morphine PCA plus a continuous basal infusion (Group II, n = 14) for 44 hr postoperatively. Pain scores with visual analogue scale (VAS) at rest, deep inspiration and with cough, sedation scores, stress hormone levels [cortisol, adrenocorticotropin (ACTH) and growth hormone (GH)] and morphine consumption were assessed, and serum morphine levels were measured at four, 20, 28 and 44 hr after surgery. Adverse effects including nausea, vomiting, constipation, urinary retention and pruritus were noted. Total blood, fluid requirements, drainage and urinary output were recorded.ResultsPostoperative morphine consumption at 44 hr was less in Group I (29.43 ±12.57 mg) than in Group II (50.14 ±16.44mg), P = 0.0006. There was no significant difference between groups in VAS scores, GH levels, blood levels of morphine and adverse effects. While VAS scores, ACTH and GH levels decreased significantly in both groups, plasma cortisol levels increased significantly in Group I only at four hours. In Group II, ACTH and cortisol were higher at four and 44 hr respectively.ConclusionPCA with morphine effectively controlled postoperative pain after cardiac surgery. The addition of a background infusion of morphine did not enhance analgesia and increased morphine consumption.RésuméObjectifComparer les effets de l’analgésie autocontrôlée (AAC), avec ou sans une perfusion de morphine de base, sur l’analgésie postopératoire et la réaction de stress à la suite d’une anesthésle cardiaque.MéthodeNotre étude a été menée en double aveugle, avec l’accord du comité d’éthique de l’université, auprès de 35 adultes consentants devant subir une opération à cœur ouvert réglée. Les patients ont reçu, soit de la morphine en AAC seule (Groupe I, n = 15), soit de la morphine en AAC plus une perfusion de base continue (Groupe II, n = 14) pendant 44 h après l’opération. Nous avons évalué: la douleur, au repos, pendant l’inspiration profonde et la toux, selon une échelle visuelle analogique (EVA), la sédation, les niveaux d’hormones de stress [cortisol, les hormones adrénocortlcotropes (ACTH) et de croissance (GH)] et la consommation de morphine, ainsi que les niveaux sériques de morphine à quatre, 20, 28 et 44 h après l’opération. Les effets indésirables, incluant les nausées, les vomissements, la constipation, la rétention urinalre et le prurit ont été notés. Le sang total, les besoins liquidiens, le débit de drainage et la diurèse ont été enregistrés.RésultatsÀ 44 h, la consommation de morphine postopératoire était plus faible dans le Groupe I (29,43 ±12,57 mg) que dans le Groupe II (50,14 ±16,44 mg), P = 0,0006. Il n’y avait pas de différence Intergroupe significative des scores à I’EVA, des niveaux de GH, des niveaux sanguins de morphine et d’effets Indésirables. Les scores à I’EVA, les niveaux d’ACTH et de GH ont diminué slgnificativement dans les deux groupes, mais le cortisol plasmatique a augmenté de façon significative dans le Groupe I, à quatre heures seulement. Dans le Groupe II, l’ACTH et le cortisol étalent respectivement plus élevés à quatre et 44 h.ConclusionL’AAC avec de la morphine réduit efficacement la douleur postopératoire en cardiochirurgie, L’ajout d’une perfusion de base de morphine n’améliore pas l’analgésie, mais augmente la consommatlon de morphine.

Magnesium sulfate pretreatment reduces myoclonus after etomidate.

Myoclonic movements and pain on injection are common problems during induction of anesthesia with etomidate. We investigated the influence of pretreatment with magnesium and two doses of ketamine on the incidence of etomidate-induced myoclonus and pain. A prospective double-blind study was performed on 100 ASA physical status I–III patients who were randomized into 4 groups according to the pretreatment drug: ketamine 0.2 mg/kg, ketamine 0.5 mg/kg, magnesium sulfate (Mg) 2.48 mmol, or normal saline. Ninety seconds after the pretreatment, anesthesia was induced with etomidate 0.2 mg/kg. Vecuronium 0.1 mg/kg was used as the muscle relaxant. An anesthesiologist, blinded to group allocation, recorded the myoclonic movements, pain, and sedation on a scale between 0–3. Nineteen of the 25 patients receiving Mg (76%) did not have myoclonic movements after the administration of etomidate, whereas 18 patients (72%) in the ketamine 0.5 mg/kg, 16 patients (64%) in the ketamine 0.2 mg/kg, and 18 patients (72%) in the control group experienced myoclonic movements (P < 0.05). We conclude that Mg 2.48 mmol administered 90 s before the induction of anesthesia with etomidate is effective in reducing the severity of etomidate-induced myoclonic muscle movements and that ketamine does not reduce the incidence of myoclonic movements.

Remifentanil versus fentanyl for short-term analgesia-based sedation in mechanically ventilated postoperative children

Background : Analgesia‐based sedation techniques are becoming more established in the intensive care unit (ICU) setting. The aim of this study was to compare remifentanil and fentanyl infusions for postoperative analgesia in pediatric ICU patients.

Effect of neostigmine on organ injury in murine endotoxemia : Missing facts about the cholinergic antiinflammatory pathway

Electrical and pharmacologic stimulation of the efferent cholinergic antiinflammatory pathway suppress the systemic inflammatory response and can prevent lethal endotoxemia. Neostigmine, a cholinergic agent, has not been tested to determine if it can prevent histopathologic organ injury in endotoxemia. In the present study, the effects of neostigmine treatment on the histopathologic organ injury inflicted by Escherichia coli endotoxin in a mouse model of septic shock was investigated. Endotoxemia in mice caused weight loss and increased spleen, liver, and lung weight. When the organs were examined for histopathologic injury, endotoxemia increased interstitial inflammation in the lungs, liver injury, and organ injury in general terms; neostigmine, at a dose of 0.1 mg/kg, failed to attenuate these effects. Although the simultaneous administration of neostigmine at a dose of 0.3 mg/kg and endotoxin decreased interstitial inflammation in the lungs, vacuolar degeneration in the liver, and total liver injury, mortality was increased with this dose in the presence of endotoxemia. We conclude that neostigmine at a dose of 0.1 mg/kg was not protective against histopathologic organ injury in mice with endotoxemia, and a higher dose (0.3 mg/kg) was not tolerated probably owing to nonspecific parasympathetic action including cardiovascular effects. Further studies are required to determine the contribution of sites in the cholinergic antiinflammatory pathway.

The Effect of HES (130/0.4) Usage as the Priming Solution on Renal Function in Children Undergoing Cardiac Surgery

Background: Experience with hydroxyethyl starch (HES) in children is limited. This study was conducted to observe the effects of HES or Ringer’s lactate (RL) usage as the priming solution on renal functions in children undergoing cardiac surgery. Methods: After ethical committee approval and parent informed consent, 24 patients were included in this prospective, randomized study. During cardiopulmonary bypass (CPB), Group I received RL and Group II received HES (130/0.4) as priming solution. Serum creatinine, blood urea nitrogen (BUN), β2-microglobulin, cystatin C, and urinary albumin and creatinine, serum, and urine electrolytes were analyzed after the induction (T1), before CPB (T2), during CPB (T3), after CPB (T4), at the end of the operation (T5), on 24th hour (T6), and on 48th hour postoperatively (T7). Fractional sodium excretion (FENa), urinary albumin/creatinine ratio, and creatinine clearance were calculated. Drainage, urine output, inotropes, diuretics, and blood requirements were recorded. Results: In both the groups, β2-microglobulin was decreased during CPB and cystatin C was decreased at T3,T4, and T5 periods (p < 0.05) and the levels remained within the normal range. Creatinine clearance did not differ in the HES group, but increased in the RL group (p < 0.05). Urine albumin/creatinine ratio was increased (p < 0.05) after CPB in the HES group, and it increased at T3, T4, and T5 in the RL group (p < 0.05). There were no differences in cystatin C, β2-microglobulin, FENa, urine albumin/creatinine ratio, creatinine clearance, total fluid amount, urine output, drainage, and inotropic and diuretic requirements between the groups. Conclusion: We conclude that usage of HES (130/0.4) did not have negative effects on renal function, and it can be used as a priming solution in pediatric patients undergoing cardiac surgery.

The Effects of Isoflurane, Sevoflurane, and Desflurane Anesthesia on Neurocognitive Outcome after Cardiac Surgery: A Pilot Study

BACKGROUND Inhalation anesthetics such as isoflurane, sevoflurane, and desflurane are widely used in clinical practice; however, there is no study for comparing these drugs in cardiac surgery with respect to postoperative cognitive outcome and S100 beta protein (S100 BP) levels. In this study, we evaluated the effect of sevoflurane, isoflurane, and desflurane anesthesia on neuropsychological outcome and S100 BP levels in patients undergoing coronary artery bypass grafting (CABG) surgery with cardiopulmonary bypass (CPB). MATERIALS AND METHODS Forty-two male patients were prospectively randomized and classified into 3 groups according to the volatile agents used; isoflurane, sevoflurane, desflurane. All patients had a sufficient education level to participate in neuropsychological testing and a normal carotid Doppler ultrasonography. Blood samples for analysis of S100 BP were collected before anesthesia (T1), before heparinization (T2), 15 minutes into CPB (T3), following protamine administration (T4), postoperatively (T5), 24 hours after the operation (T6), postoperative day 3 (T7), and postoperative day 6 (T8). The neuropsychological tests, including Mini-Mental State Examination (MMSET) and visual-aural digit span test (VADST), were administered 1 day prior to surgery and on the third and sixth postoperative days. RESULTS The postoperative third and sixth day MMSET scores and third day visual-written subtest scores in the sevoflurane group were significantly lower than in the isoflurane and desflurane groups (P < .05). S100 BP levels increased with the beginning of anesthesia in the sevoflurane and desflurane groups. Although S100 BP decreased to baseline levels on postoperative day 1 in the sevoflurane group, this was significantly higher on the third and sixth days postoperatively in the desflurane group (P < .05). In the isoflurane group, the S100 BP level was significantly higher than the baseline level only after CPB (P < .05). CONCLUSION Our study suggests that isoflurane is associated with better neurocognitive functions than desflurane or sevoflurane after on-pump CABG. Sevoflurane seems to be associated with the worst cognitive outcome as assessed by neuropsychologic tests, and prolonged brain injury as detected by high S100 BP levels was seen with desflurane.

Comparison of the Effects of Sevoflurane, Isoflurane, and Desflurane on Microcirculation in Coronary Artery Bypass Graft Surgery

OBJECTIVE This investigation was performed to compare the effects of inhalation agents on microcirculation in coronary artery bypass grafting (CABG) using orthogonal polarization spectral imaging. DESIGN This prospective and randomized study was performed in patients scheduled for CABG surgery from March through September 2010. SETTING Tertiary care university hospital. PARTICIPANTS Thirty patients undergoing elective CABG. INTERVENTIONS Patients were assigned to sevoflurane, desflurane, or isoflurane. MEASUREMENTS AND MAIN RESULTS Orthogonal polarization spectral imaging was used to evaluate the sublingual microcirculation. Hemodynamic variables (heart rate, mean arterial pressure, central venous pressure, cardiac output, and pulmonary capillary wedge pressure), laboratory parameters (hematocrit, lactate, and potassium), and microcirculatory variables (total vascular density [TVD] [mm/mm(2)], microvascular flow index [MFI] [arbitrary units], perfused vessel density [PVD] [mm/mm(2)], and proportion of perfused vessels [PPV] [percentage] were obtained before induction, after induction, during cardiopulmonary bypass, at the end of surgery, and 24 hours after surgery. The greatest alterations in microcirculation parameters were found during cardiopulmonary bypass. In the sevoflurane group, TVD (14.7%), PVD (22%), PPV (5.97%, p < 0.05), and MFI (7.69%, p > 0.05) were decreased. In the isoflurane group, TVD (14.7%) and PVD (20.3%) were decreased, whereas PPV (1.69%) and MFI (17.99%) were increased (p < 0.05). In the desflurane group, there were no changes in TVD and PVD, but MFI (8.99%, p > 0.05) and PPV (1.48%, p < 0.05) were increased in the small vessels. These changes returned to their initial values 24 hours postoperatively. CONCLUSIONS Sevoflurane had a negative effect on the microcirculation. Isoflurane decreased vascular density and increased flow. Desflurane produced stable effects on the microcirculation. These inhalation agents induced transient alterations in microvascular perfusion.