Nilson Antunes

Inflamação sistêmica causada pela periodontite crônica em pacientes vítimas de ataque cardíaco isquêmico agudo

OBJECTIVE Infectious and inflammatory processes mediated by bacteria in distant sites have been described as a risk factor for acute ischemic heart disease (AIHD). METHODS One hundred one patients with AIHD with and without chronic periodontitis (CP) were included in this study. Patients were admitted to the HC UNICAMP and stratified into three groups: in group 1, we selected patients with severe chronic periodontitis (31 men and 19 women, mean age 55.1 +/- 11.29 years old); the group 2 with mild chronic periodontitis (40 men and 28 women, mean age 54.8 +/- 10.37 years old) and group 3 represented by the toothless (43 men and 20 women, mean age 67.5 +/- 8.55 years old). Blood samples were collected to measure the lipid profiles, hematological and blood glucose levels. In addition, biopsies of seventeen coronary arteries with atherosclerosis and an equal number of internal mammary arteries without atherosclerotic degeneration in group 1 were investigated. Statistical analysis by analysis of variance (ANOVA) and Scheffé test for multiple comparisons was performed. RESULTS Triglyceride and LDL levels were elevated in group 1 than in group 2. HDL were reduced by 20% in group 1 and remained reduced by 8% in toothless. Blood glucose was higher in group 1. DNA of periodontal bacteria was detected in 58.8% of the coronary arteries. CONCLUSIONS Patients with (AIHD) and severe chronic periodontitis may have altered lipid profile, as well as microorganisms associated with CP can permeate into coronary vessels.AbstractObjective: Infectious and inflammatory processesmediated by bacteria in distant sites have been described asa risk factor for acute ischemic heart disease (AIHD). Methods: One hundred one patients with AIHD with andwithout chronic periodontitis (CP) were included in thisstudy. Patients were admitted to the HC UNICAMP andstratified into three groups: in group 1, we selected patientswith severe chronic periodontitis (31 men and 19 women,mean age 55.1 ± 11.29 years old); the group 2 with mildchronic periodontitis (40 men and 28 women, mean age 54.8± 10.37 years old) and group 3 represented by the toothless(43 men and 20 women, mean age 67.5 ± 8.55 years old).Blood samples were collected to measure the lipid profiles,hematological and blood glucose levels. In addition, biopsiesof seventeen coronary arteries with atherosclerosis and anequal number of internal mammary arteries withoutatherosclerotic degeneration in group 1 were investigated.Statistical analysis by analysis of variance (ANOVA) andScheffe test for multiple comparisons was performed.

Analysis of the hydrodynamic profile in different roller pumps models used in cardiopulmonary bypass

OBJECTIVE Among the equipments used in cardiopulmonary bypass the roller pumps have great importance with various models available from several manufacturers. The calibration is an important factor in hemolysis rates and its potential is different in each. Researchers do not always approach details on the pump bed profiles assuming that the standardized calibration settings ensure equal and comparable values for all models of roller pumps. We have mainly two methods for calibration of pumps which also interferes on the hemolytic potential. In both of them, the characteristics of fluid impulsion defined by the pump bed design are not considered. The aim of this study is to compare the hydrodynamic profile of three models of roller pumps available in the Brazilian market. METHOD The rollers occlusion was performed by measures of drop and dynamic calibration. Two different silicone diameter tubes were used (3/8 x 1/16 and 1/2 x 3/32 inches). RESULTS The profiles showed differences in their variances, P<0.01 for drop rate measures and P<0.0001 for dynamic calibration. Different changes in pressure were found between the pumps analyzed (P<0.002). CONCLUSION The measures of occlusion are dependent on the design of the pump bed and comparisons involving roller pumps should be performed with caution. Blood tests should be performed to verify the influence of changes in hemolysis pressure.

The influence of the residual stress in silicone tubes in the calibration methods of roller pumps used in cardiopulmonary bypass.

The rotation of rollers in cardiopulmonary bypass pumps propels the blood through various devices to reach the patient. Very occlusive settings may squeeze red blood cells, whereas a nonocclusive setting may result in retrograde flow. Occlusion of roller pumps may be regulated either by measuring the drop rate or by dynamic calibration. This study evaluated the influence of silicone tubing residual stress found on pump regulation. Silicone tubes obtained from two different suppliers were used in 6-inch DeBakey roller pumps. The variations occurring over time in the measurements of drop rate, dynamic calibration, and tube residual stress were analyzed. Covariance analysis of the four linear regressions has shown a progressive and accentuated reduction in drop rate (p < 0.002). It is noticeable that the angular coefficients of the drop rate measurements of the four silicone tubes are the same (p > 0.56). This reduction in drop rate measurements may affect the regulation of the pumps before surgical procedures. One probable cause for this reduction is the residual stress found in the silicone tubes. Settings based on the dynamic calibration process tended to be repeated over time. Simple linear regression test (angular coefficient equals zero) has shown a p > 0.79 showing no interference of the silicone tubes residual stress on dynamic calibration, suggesting that one should use this method to calibrate roller pumps.

Use of (all-blood) miniplegia versus crystalloid cardioplegia in an experimental model of acute myocardial ischemia.

Abstract  Purpose: Several methods of myocardial protection have been used. The use of all‐blood solutions modified with glutamate and aspartate has increased. Its use in situations of acute ischemia provides improved contractile function, “resuscitating” the previously lesioned muscle. The dilution preconized by literature is around 25% of the hematocrit. The present study evaluates an all‐blood cardioplegia solution with tepid 1% dilution, denominated miniplegia. Material and method: Pigs of the Large‐White breed were used with an isolated heart and perfused with blood of a support animal. Three groups (n = 7 per group) were designated with the following treatments: Control group (CO), St. Thomas solution (ST), continuous normothermic all‐blood solutions (SG). After the stabilization period, systolic pressure (PS), diastolic pressure (PD), developed pressure (PD), stress of the wall, elastance, and passive stiffness were recorded. The hearts were submitted to 30 minutes of regional ischemia with the clamping of the anterior interventricular artery, and subsequently to 90 minutes of global ischemia with the use of the three different treatments during this period. At the beginning of global ischemia, the coronary clamp was removed. The hearts were again reperfused. Upon three minutes into reperfusion the hearts were defibrillated when necessary. Measurements were taken every 30 minutes to 90 minutes into reperfusion. Results: The SG presented a better recovery of the ventricular function in several of the parameters recorded. The ST group was inferior to the SG group, which in turn was superior to the CO group in some of the parameters analyzed. A higher number of defibrillations were needed to reestablish coordinated heart beats in the ST and CO groups. There were no differences related to the percentage of wet weight between the SG and ST groups, and the percentage was higher in the CO group. Conclusion: The use of all‐blood miniplegia provided superior protection when compared to global ischemia or crystalloid cardioplegia in acutely ischemic hearts. The model employed is very close to the clinical situation due to the use of blood as a perfusate.

Thoracoabdominal aneurysm rupture: a modification of the visceral perfusion circuit

A patient with ruptured type IV thoracoabdominal aortic aneurysm (TAAA), underwent surgical treatment utilizing visceral perfusion assisted by a centrifugal pump and neonatal membrane oxygenator. This circuit allows visceral perfusion with oxygenated blood during the ischemic period and the fast infusion of intravenous volume after clamp removal.

The effect on hemolysis of the raceway profile of roller pumps used in cardiopulmonary bypass.

This study aims at the influence on hemolysis of the differences between the maximum and minimum amplitudes of pressure in the outlet of three roller pump models adjusted by dynamic calibration method. Tests were performed with silicone tubes (½ × 3/16 inches) in fluid analogous to blood and fresh bovine blood from slaughterhouse. Tests with analogous solution to blood were performed varying the dynamic calibration pressure between 78 and 500 mm Hg. Tests with fresh bovine blood were performed with the three pumps simultaneously, and pressure differences and free hemoglobin in the plasma were measured during 360 minutes. Tests with both analogous solution to blood and fresh bovine blood showed differences of mean pressures of pump 2 related to pumps 1 and 3 (p < 0.01). The different models of roller pumps analyzed presented differences in pressure amplitudes (p < 0.01) and hemolysis (p < 0.01) adjusted for the same dynamic calibration pressure. Raceway profile of pump 2 resulted in smaller pressure amplitude, implying lower hemolysis rate compared with pumps 1 and 3.

Hemolysis in extracorporeal circulation: relationship between time and procedures

INTRODUCTION Extracorporeal circulation (EC) is very important in cardiac surgery but causes significant damage to the blood, including hemolysis. OBJECTIVE To quantify the rate of hemolysis at different times during EC in elective coronary artery bypass grafting. METHODS We measured rates of hemolysis of 22 patients at 6 different times during myocardial revascularization during EC: T0 - before the start of EC, T1 - five minutes after of the EC initiation, T2 - 30 minutes of EC, T3 - immediately before the aortic unclamping, T4 - immediately before passage of the residual volume to the patient and T5 - five minutes after the passage of the residual volume to the patient. Rates of hemolysis were calculated between the intervals of time: T0-T1; T1-T2; T2-T3; T3-T4 and T4-T5. RESULTS The first 5 minutes after the EC showed the highest rate of hemolysis (P = 0.0003) compared to the others calculated rates, representing 29% of the total haemolysis until T4 (Immediately before passage of the residual volume to the patient). CONCLUSION There were no significant changes in the rate of hemolysis during the suction in the aortic root (P> 0.38), nor with the procedure used for the passage of the residual volume of blood in the circuit to the patient.

Brazilian perfusionists and arterial roller pump adjustment: comparison between static and dynamic calibration method

INTRODUCTION Roller pumps play an important role in extracorporeal circulation. However, occlusion of the rollers should be adequately performed and this can be adjusted mainly by two methods: static and dynamic. OBJECTIVE To investigate how the Brazilian perfusionists adjust arterial roller pumps in their services and evaluate the application of a Device to Assist Calibration (DAC) that facilitates roller adjustment by the dynamic calibration method. METHODS We installed a roller pump with accessories to perform adjustment by drop rate (static calibration) and dynamic calibration methods during the XXVIII Brazilian Congress of Extracorporeal Circulation. Perfusionists were asked to adjust the roller pump according to the procedure they usually do in their service. After each adjustment pressure was measured by dynamic calibration method with DAC. The research was approved by the Research Ethics Committee of UNICAMP, Nº 1144/2010. RESULTS There were 56 perfusionists in this study. Pressure average of 56 measurements of dynamic calibration was 434 ± 214 mmHg; 76% of measurements were within the recommended range for the use of the dynamic calibration method (between 150 and 500 mmHg). CONCLUSION Brazilian perfusionists tend to adjust roller pumps with less occlusive settings. The amplitudes of the dynamic calibration pressure tend to be smaller for more experienced perfusionists because their skills increase with time. The device can be used by the perfusionist to adjust roller pumps with greater accuracy and mainly repeatability in few minutes.INTRODUCTION: Roller pumps play an important role in extracorporeal circulation. However, occlusion of the rollers should be adequately performed and this can be adjusted mainly by two methods: static and dynamic. OBJECTIVE: To investigate how the Brazilian perfusionists adjust arterial roller pumps in their services and evaluate the application of a Device to Assist Calibration (DAC) that facilitates roller adjustment by the dynamic calibration method. METHODS: We installed a roller pump with accessories to perform adjustment by drop rate (static calibration) and dynamic calibration methods during the XXVIII Brazilian Congress of Extracorporeal Circulation. Perfusionists were asked to adjust the roller pump according to the procedure they usually do in their service. After each adjustment pressure was measured by dynamic calibration method with DAC. The research was approved by the Research Ethics Committee of UNICAMP, No 1144/2010. RESULTS: There were 56 perfusionists in this study. Pressure average of 56 measurements of dynamic calibration was 434 ± 214 mmHg; 76% of measurements were within the recommended range for the use of the dynamic calibration method (between 150 and 500 mmHg). CONCLUSION: Brazilian perfusionists tend to adjust roller pumps with less occlusive settings. The amplitudes of the dynamic calibration pressure tend to be smaller for more experienced perfusionists because their skills increase with time. The device can be used by the perfusionist to adjust roller pumps with greater accuracy and mainly repeatability in few minutes.

Auxiliary device for calibration of roller pumps: development and experimental results

Introduction: Roller pumps are commonly used in surgeries involving extracorporeal circulation and its regulation may influence the hemolysis rate. Objective: To describe an auxiliary device for adjusting roller pumps using the dynamic calibration method and show preliminary results of its application in surgical procedures. Method: The device was tested in the laboratory environment with three disposable pressure transducers normally used in surgeries. In the operation room, tests were carried out with two groups of patients. Free hemoglobin plasma rates were measured, 5 minutes after perfusion started and immediately before the passage of the residual volume of the pump. For Group 1 (n = 22), occlusion measurements were carried out using the drop rate method and for Group 2 (n = 18), measurements were carried out using the auxiliary device and 300 mmHg calibration (mean pressure for the dynamic calibration method). Results: The auxiliary calibration device has shown calibration results statistically equal to those obtained with a reference device in the laboratory environment. We have found less variability of hemolysis rates in the operating room, using the auxiliary device and we did not observe any influence of unbalanced rollers in the hemolysis rates.

Does the roller pump adjustment in cardiopulmonary bypass settings influence hemolysis

Introduction Roller pumps are widely used in procedures involving cardiopulmonary bypass (CPB) due to their ease of operation and maintenance, safety, and cost. Several studies in the literature have compared the use of roller pumps with centrifugal pumps, but the influence of the roller pump adjustment on hemolysis has been poorly explored. Methods Measurements of hemolysis rates were carried out in 86 patients. The pump was adjusted by the dynamic calibration method, which was performed by an auxiliary device, and the patients were grouped according to the pump calibration: Group 1 (n = 20) 75 mmHg; Group 2 (n = 24) 150 mmHg; Group 3 (n = 22) 300 mmHg and Group 4 (n = 21) 450 mmHg. The hemolysis rates were measured at 4 different times during CPB (TO: before the surgical procedure; T1: 5 minutes after the start of CPB; T2: 30 minutes of CPB; and T3: 5 minutes after the CPB procedure). Hemolysis rates were calculated between the time intervals T0–T1, T1–T2, and T0–T3. Results No difference in hemolysis rates was observed between the groups (p>0.31). During the first 5 minutes of CPB, hemolysis represented 35.5% of the total hemolysis and no significant difference was found between groups (p>0.60). Conclusions Calibration of roller pumps by the dynamic method did not influence the hemolysis rates. Additionally, the hemolysis during the first 5 minutes of CPB accounted for ∼1/3 of the total hemolysis.