Tissue expander complications in plastic surgery: a 10-year experience

INTRODUCTION: Tissue expanders have been of great value in plastic surgery. Tissue expansion was developed for a specific indication; however, within a very short time, the concept of tissue expansion found wide applicability. From 1990 to 1999, 315 expanders in 164 patients were utilized. A retrospective analysis of complications and prognostic factors for complications were done. METHODS: The indications for tissue expansion were burns (50%), trauma (32%), and sequelae of previous surgery (8.8%). The expanders were inserted most frequently in the scalp, trunk and neck. RESULTS: There were 22.2% of complications and the most common were expander exposure (50%), infection (24%) and bad function of the expander (12.8%). The present study revealed an increased rate of minor complications in the group of 0 to 10 years of age and an increased rate of major complications for face and neck expansions compared to trunk expansion. There were no increased complication rates for the other age and anatomic site groups, previous expansion, concomitant expansion and type of expander used. CONCLUSIONS: The outcomes from tissue expansion procedures done in our hospital are similar to those reported in the literature. Tissue expansion is a good and safe technique.

Surgery information reduces anxiety in the pre-operative period

PURPOSE: Patients preparing to undergo surgery should not suffer needless anxiety. This study aimed to evaluate anxiety levels on the day before surgery as related to the information known by the patient regarding the diagnosis, surgical procedure, or anesthesia. METHOD: Patients reported their knowledge of diagnosis, surgery, and anesthesia. The Spielberger State-Trait Anxiety Inventory (STAI) was used to measure patient anxiety levels. RESULTS: One hundred and forty-nine patients were selected, and 82 females and 38 males were interviewed. Twenty-nine patients were excluded due to illiteracy. The state-anxiety levels were alike for males and females (36.10 ± 11.94 vs. 37.61 ± 8.76) (mean ± SD). Trait-anxiety levels were higher for women (42.55 ± 10.39 vs. 38.08 ± 12.25, P = 0.041). Patient education level did not influence the state-anxiety level but was inversely related to the trait-anxiety level. Knowledge of the diagnosis was clear for 91.7% of patients, of the surgery for 75.0%, and of anesthesia for 37.5%. Unfamiliarity with the surgical procedure raised state-anxiety levels (P = 0.021). A lower state-anxiety level was found among patients who did not know the diagnosis but knew about the surgery (P = 0.038). CONCLUSIONS: Increased knowledge of patients regarding the surgery they are about to undergo may reduce their state-anxiety levels.

Monitoring the early stiffness development in epoxy adhesives for structural strengthening

The present work aimed to assess the early-age evolution of E-modulus of epoxy adhesives used for Fibre-Reinforced Polymer (FRP) strengthening applications. The study involved adapting an existing technique devised for continuous monitoring of concrete stiffness since casting, called EMM-ARM (Elasticity Modulus Measurement through Ambient Response Method) for evaluation of epoxy stiffness. Furthermore, monotonic tensile tests according to ISO standards and cyclic tensile tests were carried out at several ages. A comparison between the obtained results was performed in order to better understand the performance of the several techniques in the assessment of stiffness of epoxy resins. When compared to the other methodologies, the method for calculation of E-modulus recommended by ISO standard led to lower values, since in the considered strain interval, the adhesive had a non-linear stress–strain relationship. The EMM-ARM technique revealed its capability in clearly identifying the hardening kinetics of epoxy adhesives, measuring the material stiffness growth during the entire curing period. At very early ages the values of Young׳s modulus obtained with quasi-static tests were lower than the values collected by EMM-ARM, due to the fact that epoxy resin exhibited a significant visco-elastic behaviour.

Effects of bariatric surgery on the central nervous system and eating behavior in humans: a systematic review on the neuroimaging studies

INTRODUCTION: Neuroimaging studies suggest that obese people might show hyperactivity of brain areas regarding reward processing, and hypoactivity of brain areas concerning cognitive control, when exposed to food cues. Although the effects of bariatric surgery on the central nervous system and eating behavior are well known, few studies have used neuroimage techniques with the aim of investigating the central effects of bariatric surgery in humans. OBJECTIVES: This paper systematically and critically reviews studies using functional neuroimaging to investigate changes on the patterns of activation of central areas related to the regulation of eating behavior after bariatric surgery. METHOD: A search on the databases Medline, Web of Science, Lilacs and Science Direct on Line, was conducted in February 2013, using the keywords "Neuroimaging", "Positron-Emission Tomography", "Magnetic Resonance Imaging", "Gastric Bypass", "Gastroplasty", "Jejunoileal Bypass", "Bariatric Surgery". RESULTS: Seven manuscripts were included; the great majority studied the central effects of Roux en Y gastric bypass, using positron emission tomography or functional magnetic resonance. CONCLUSIONS: Bariatric surgery might normalize the activity of central areas concerned with reward and incentive salience processing, as the nucleus accumbens and mesencephalic tegmental ventral area, as well as circuitries processing behavioral inhibition, as the dorsolateral prefrontal cortex.

Detection of the viable myocardium. A perfusion scintigraphic study, before and after coronary bypass surgery in myocardial infarction patients

OBJECTIVE: To compare single-photon-emission computed tomography (SPECT) imaging scans using 201Tl and 99mTc-MIBI in detection of viable myocardium, in regions compromised by infarction. METHODS: Thirty-two (59.3±9.8 years old and 87% male) myocardial infarction patients were studied. All had Q waves on the ECG and left ventricle ejection fraction of <50%. They underwent coronary and left ventricle angiographies and SPECT before (including 201Tl reinjection) and after coronary artery bypass surgery (CABG). Improvement in perfusion observed after surgery was considered the gold standard for myocardial viability. RESULTS: Among 102 studied regions of the heart, there were 40 (39.2%) areas of transient perfusion defects in the conventional protocol with 201Tl and 52 (51.0%) after reinjection. Therefore, 12/62 (19.4%) more viable regions were identified by reinjection. Using 99mTc-MIBI, only 14 (13.7%) regions with transient defects were identified, all of which were seen also in 201Tl protocols. After surgery, 49 of a total of 93 regions analyzed (52.7%) were viable. Sensitivity, specificity, accuracy, positive and negative prediction values were, respectively, 201Tl SPECT scans - 65.3%, 90.9%, 77.4%, 88.9% and 70.2%, reinjection protocol with 201Tl scans - 81.6%, 81.8%, 81.7%, 83.3% and 80.0%; 99mTc-MIBI SPECT scans - 20.4%, 90.9%, 53.8%, 71.4% and 50.6%. Logistic regression demonstrated that the reinjection protocol with 201Tl was the best predictor of viability (P<0.001). CONCLUSION: Our data suggest the election of 201Tl for viability studies, especially when using the reinjection protocol.

Invasive hemodynamic monitoring in the postoperative period of cardiac surgery

OBJETIVE: To assess the hemodynamic profile of cardiac surgery patients with circulatory instability in the early postoperative period (POP). METHODS: Over a two-year period, 306 patients underwent cardiac surgery. Thirty had hemodynamic instability in the early POP and were monitored with the Swan-Ganz catheter. The following parameters were evaluated: cardiac index (CI), systemic and pulmonary vascular resistance, pulmonary shunt, central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), oxygen delivery and consumption, use of vasoactive drugs and of circulatory support. RESULTS: Twenty patients had low cardiac index (CI), and 10 had normal or high CI. Systemic vascular resistance was decreased in 11 patients. There was no correlation between oxygen delivery (DO2) and consumption (VO2), p=0.42, and no correlation between CVP and PCWP, p=0.065. Pulmonary vascular resistance was decreased in 15 patients and the pulmonary shunt was increased in 19. Two patients with CI < 2L/min/m² received circulatory support. CONCLUSION: Patients in the POP of cardiac surgery frequently have a mixed shock due to the systemic inflammatory response syndrome (SIRS). Therefore, invasive hemodynamic monitoring is useful in handling blood volume, choice of vasoactive drugs, and indication for circulatory support.

Outcome of acute renal failure associated with cardiac surgery in infants

OBJECTIVE: To analyze the impact of acute renal failure (ARF) on the evolution of infants undergoing cardiac surgery. METHODS: We assessed 15 infants undergoing cardiac surgery who developed (ARF). Their demographic, clinical and surgical data, and evolution were analyzed. RESULTS: Their mean age was 4.4±4.0 months (8 days to 24 months). Twelve infants were males, and 4 patients already had ARF at surgery. The primary cause of ARF was immediate acute cardiac dysfunction in 10 infants, cardiac dysfunction associated with sepsis in 2 infants, and isolated sepsis in 3 infants. All children depended on mechanical ventilation during their postoperative period, 14 infants used vasoactive drugs, and 11 had an infectious process associated with ARF. Thirteen infants required dialytic treatment. Eleven infants developed oluguric ARF, and all had to undergo peritoneal dialysis; of the 4 patients with non-oliguric, 2 required dialysis, the main indication being hypervolemia. Of these 13 dialyzed infants, 4 died in the first 24 hours because of the severity of the underlying cardiac disease (mean urea level of 49±20 mg/dl). The mortality rate for the entire group was 60% , and it was higher among the patients with oliguria ARF (73% vs 25%, p<0.001). The cause of death was acute cardiac dysfunction in 6 infants (early type-1ARF) and sepsis in the 3 remaining infants (late type-2 ARF). CONCLUSION: The mortality rate of ARF associated with cardiac surgery in infants was hight, being higher among children with oliguria; peritoneal dialysis was indicated due to clinically uncontrolled hypervolemia and not to the uremic hypercatabolic state.

Postoperative necrotizing fasciitis of the thorax in cardiac surgery

Necrotizing fasciitis is a rare soft tissue infection and a life-threatening emergency, often fatal. Its incidence and management are described plentifully in the medical literature regarding the most common anatomical sites involved like the abdomen, lower and upper limbs, and perineum. However, available data and case reports of chest wall necrotizing fasciitis after thoracic procedures are scarce, mainly after major cardiac operations. We report and discuss a case of necrotizing fasciitis of the chest wall occurring in the immediate postoperative period of a cardiac procedure, and include a brief review of the concepts, pathophysiology, and treatment reported in the medical literature. We emphasize the need for early diagnosis and urgent and effective surgical debridement. Of importance is the fact that we have not found any references in the literature to cases similar or equal to the one we describe here, which occurred in the postoperative period of a cardiac procedure.

Assessment of splanchnic perfusion with gastric tonometry in the immediate postoperative period of cardiac surgery in children

OBJECTIVE - A prospective, nonrandomized clinical study to assess splanchnic perfusion based on intramucosal pH in the postoperative period of cardiac surgery and to check the evolution of patients during hospitalization. METHODS - We studied 10 children, during the immediate postoperative period after elective cardiac surgery. Sequential intramucosal pH measurements were taken, without dobutamine (T0) and with 5mcg/kg/min (T1) and 10 (T2) mcg/kg/min. In the pediatric intensive care unit, intramucosal pH measurements were made on admission and 4, 8, 12, and 24 hours thereafter. RESULTS - The patients had an increase in intramucosal pH values with dobutamine 10mcg/kg/min [7.19± 0.09 (T0), 7.16±0.13(T1), and 7.32±0.16(T2)], (p=0.103). During the hospitalization period, the intramucosal pH values were the following: 7.20±0.13 (upon admission), 7.27±0.16 (after 4 hours), 7.26±0.07 (after 8 hours), 7.32±0.12 (after 12 hours), and 7.38±0.08 (after 24 hours), (p=0.045). No deaths occurred, and none of the patients developed multiple organ and systems dysfunction. CONCLUSION - An increase in and normalization of intramucosal pH was observed after dobutamine use. Measurement of intramucosal pH is a type of monitoring that is easy to perform and free of complications in children during the postoperative period of cardiac surgery.

Myocardial Revascularization Surgery with Regional Anesthesia Without an Endotracheal Tube in Conscious Patients

OBJECTIVE: To report initial experience with myocardial revascularization surgery (MRS) performed on patients who were totally awake and without an endotracheal tube.METHODS: Between January 1994 and May 2001, 272 patients underwent MRS without extracorporeal circulation. In 24, the operations were performed without the use of an endotracheal tube and with the patients totally awake and breathing normally. The age ranged from 51-75 years with the predominant male sex. Epidural thoracic administratios of the anesthesia was performed. Surgery was performed through a habitual anterolateral thoracotomy. During the entire procedure, the left lung remained partially collapsed.RESULTS: The 24 patients progressed well through the surgery. Pneumothorax time ranged from 70-190 minutes. No electrocardiographic, echocardiographic, or enzymatic alterations occurred that characterized pre- and postoperative infarcts. Twenty-three patients were stable enough to be released after 24 hours.CONCLUSION: This technique could be performed on an large number of selected patients. However, more experience is necessary.

Prognostic value of technetium-99m-labeled single-photon emission computerized tomography in the follow-up of patients after their first myocardial revascularization surgery

OBJECTIVE: To assess the prognostic value of Technetium-99m-labeled single-photon emission computerized tomography (SPECT) in the follow-up of patients who had undergone their first myocardial revascularization. METHODS: We carried out a retrospective study of 280 revascularized patients undergoing myocardial scintigraphy under stress (exercise or pharmacological stress with dipyridamole) and at rest according to a 2-day protocol. A set of clinical, stress electrocardiographic and scintigraphic variables was assessed. Cardiac events were classified as "major" (death, infarction, unstable angina) and "any" (major event or coronary angioplasty or new myocardial revascularization surgery). RESULTS: Thirty-six major events occurred as follows: 3 deaths, 11 infarctions, and 22 unstable anginas. In regard to any event, 22 angioplasties and 7 new surgeries occurred in addition to major events, resulting a total of 65 events. The sensitivity of scintigraphy in prognosticating a major event or any event was, respectively, 55% and 58%, showing a negative predictive value of 90% and 83%, respectively. Diabetes mellitus, inconclusive stress electrocardiography, and a scintigraphic visualization of left ventricular enlargement were significant variables for the occurrence of a major event. On multivariate analysis, abnormal myocardial scintigraphy was a predictor of any event. CONCLUSION: Myocardial perfusion tomography with Technetium-99m may be used to identify high-risk patients after their first myocardial revascularization surgery.

Predictive factors of in-hospital mortality and of severe perioperative complications in myocardial revascularization surgery

OBJECTIVE: To investigate preoperative predictive factors of severe perioperative intercurrent events and in-hospital mortality in coronary artery bypass graft (CABG) surgery and to develop specific models of risk prediction for these events, mainly those that can undergo changes in the preoperative period. METHODS: We prospectively studied 453 patients who had undergone CABG. Factors independently associated with the events of interest were determined with multiple logistic regression and Cox proportional hazards regression model. RESULTS: The mortality rate was 11.3% (51/453), and 21.2% of the patients had 1 or more perioperative intercurrent events. In the final model, the following variables remained associated with the risk of intercurrent events: age ³ 70 years, female sex, hospitalization via SUS (Sistema Único de Saúde - the Brazilian public health system), cardiogenic shock, ischemia, and dependence on dialysis. Using multiple logistic regression for in-hospital mortality, the following variables participated in the model of risk prediction: age ³ 70 years, female sex, hospitalization via SUS, diabetes, renal dysfunction, and cardiogenic shock. According to the Cox regression model for death within the 7 days following surgery, the following variables remained associated with mortality: age ³ 70 years, female sex, cardiogenic shock, and hospitalization via SUS. CONCLUSION: The aspects linked to the structure of the Brazilian health system, such as factors of great impact on the results obtained, indicate that the events investigated also depend on factors that do not relate to the patient's intrinsic condition.

Risk stratification with troponin I in patients undergoing myocardial revascularization surgery

OBJECTIVE: To determine the immediate behavior and the prognostic value in terms of late survival of serum troponin I measurement in patients undergoing myocardial revascularization surgery with extracorporeal circulation. METHODS: We studied 88 random patients, 65 (73.8%) of the male sex, who underwent myocardial revascularization surgery with extracorporeal circulation. Troponin measurements were performed as follows: in the preoperative period, right after intensive care unit admission, and on the first and second postoperative days. Values below 0.1 nanogram per milliliter (ng/mL) were considered normal. The cut points for late prognostic assessment were 0.5 ng/mL; 1 ng/mL; 2.5 ng/mL; and 5 ng/mL. RESULTS: The serum troponin I levels were elevated on the first postoperative day, suggesting the occurrence of specific myocardial damage. Patients with a poor prognosis could be identified, because the serum levels above 2.5 ng/mL and 5 ng/mL in the postoperative period resulted, respectively, in mortality rates of 33% and 50% in a maximum 6-month follow-up. CONCLUSION: Troponin I values around 2.5 ng/mL in the postoperative period should call attention to the need for more aggressive diagnostic or therapeutical measures.

Behavior of inflammatory markers of myocardial injury in cardiac surgery: laboratory correlation with the clinical picture of postpericardiotomy syndrome

OBJECTIVE: To verify the association of serum markers of myocardial injury, such as troponin I, creatinine kinase, and creatinine kinase isoenzyme MB, and inflammatory markers, such as tumor necrosis factor alpha (TNF-alpha), C-reactive protein, and the erythrocyte sedimentation rate in the perioperative period of cardiac surgery, with the occurrence of possible postpericardiotomy syndrome. METHODS: This was a cohort study with 96 patients undergoing cardiac surgery assessed at the following 4 different time periods: the day before surgery (D0); the 3rd postoperative day (D3); between the 7th and 10th postoperative days (D7-10); and the 30th postoperative day (D30). During each period, we evaluated demographic variables (sex and age), surgical variables (type and duration , extracorporeal circulation), and serum dosages of the markers of myocardial injury and inflammatory response. RESULTS: Of all patients, 12 (12.5%) met the clinical criteria for a diagnosis of postpericardiotomy syndrome, and their mean age was 10.3 years lower than the age of the others (P=0.02). The results of the serum markers for tissue injury and inflammatory response were not significantly different between the 2 assessed groups. No significant difference existed regarding either surgery duration or extracorporeal circulation. CONCLUSION: The patients who met the clinical criteria for postpericardiotomy syndrome were significantly younger than the others were. Serum markers for tissue injury and inflammatory response were not different in the clinically affected group, and did not correlate with the different types and duration of surgery or with extracorporeal circulation.