Prognostic value of FDG uptake in early stage non-small cell lung cancer

Background: Non-small cell lung cancer (NSCLC) has a poor prognosis even for early stages of the disease (stage I and II). We studied the prognostic value of PET FDG in patients with completely resected stage I and II NSCLC. Methods: Retrospective study of 96 patients with NSCLC whose staging included ¹⁸F-FDG PET (fluoro deoxy glucose positron emission tomography). Histopathological stage was either stage I (75) or stage II (n = 21). FDG uptake was measured as maximal standardized uptake value for body weight (SUVmax). Mean follow-up was 45 ± 30 months (1–142 months). Overall and cancer-free survival rates were recorded. Results: SUVmax were higher for stage II than for stage I (10.5 ± 4.5 vs 8.5 ± 5, p = 0.04). Mean tumor volumes were equivalent for both stages (33 cm³, p = 0.18), excluding a partial volume effect. The median SUVmax in the whole study population was 7.8. The median survival was significantly longer in patients with a lower (SUVmax ≤ 7.8) FDG uptake (127 months vs 69 months, p = 0.001). For stage I tumors (n = 75), high FDG uptake was significantly associated with reduced median survival: 127 months if SUVmax ≤ 7.8 and 69 months if SUVmax > 7.8 (p = 0.001). For stage II tumors (n = 21), no statistical difference was observed: 72 months vs 40 months for SUVmax ≤ 7.8 and for SUVmax > 7.8, respectively (p = 0.11), although there was a clear trend towards reduced survival for highly metabolic tumors. Disease-free survival was also significantly better for lower metabolic tumors: 96.1 months vs 87.7 months (p = 0.01). Conclusion: High FDG uptake is associated with reduced overall survival and disease-free survival of patients with completely resected stage I–II NSCLC. Whether patients with highly metabolic tumors should undergo a closer postoperative surveillance or adjuvant chemotherapy has to be addressed in a properly designed prospective trial.     

Effects of pre-natal and early post-natal undernutrition on adult internal thoracic artery function

Objective: Previous studies in humans and animals have suggested that undernutrition in utero and in early post-natal life may lead to altered vascular function in a number of peripheral arteries. We investigated the effect of pre- and post-natal nutrient restriction on the vascular reactivity of the left internal thoracic artery using a sheep model. Methods: Welsh mountain ewes were mated and assigned to three dietary groups: (1) 100% of total nutritional requirements (control, n = 6); (2) 50% of total nutritional requirements during the first 31 days of gestation (n = 6); and (3) 50% nutritional restriction during the first 31 days of gestation, followed by a restriction in the diet of their offspring 12–25 weeks post-natally, designed to produce a 15% reduction in growth trajectory (n = 7). The male offspring were sacrificed at 130 weeks; the left internal thoracic artery was mounted onto a wire myograph and the reactivity of the vessel to various agonists measured. Results: The offspring of animals who underwent an early gestation nutrient restriction had a significantly increased basal tone (0.41 ± 0.25 vs 6.34 ± 1.35, p = 0.015) and sensitivity to phenylephrine (log EC₅₀: −6.23 ± 0.04 M vs −5.74 ± 0.17 M, p = 0.036) as compared with control animals. However, this phenomenon was not seen in animals that underwent both pre- and post-natal nutrient restriction. Conclusions: Pre-natal undernutrition increases the basal tone and sensitivity of the left internal thoracic artery to phenylephrine. This effect is significantly attenuated by continued undernutrition in early post-natal life. These experiments suggest that in utero and early post-natal undernutrition may be important determinants of graft function in later life.     

Jugular venous valved conduit (Contegra) matches allograft performance in infant truncus arteriosus repair

Objective: Limited availability and durability of allograft conduits require that alternatives be considered. We compared bovine jugular venous valved (JVV) and allograft conduit performance in 107 infants who survived truncus arteriosus repair. Methods: Children were prospectively recruited between 2003 and 2007 from 17 institutions. The median z-score for JVV (n = 27, all 12 mm) was +2.1 (range +1.2 to +3.2) and allograft (n = 80, 9–15 mm) was +1.7 (range −0.4 to +3.6). Propensity-adjusted comparison of conduit survival was undertaken using parametric risk-hazard analysis and competing risks techniques. All available echocardiograms (n = 745) were used to model deterioration of conduit function in regression equations adjusted for repeated measures. Results: Overall conduit survival was 64 ± 9% at 3 years. Conduit replacement was for conduit stenosis (n = 16) and/or pulmonary artery stenosis (n = 18) or regurgitation (n = 1). The propensity-adjusted 3-year freedom from replacement for in-conduit stenosis was 96 ± 4% for JVV and 69 ± 8% for allograft (p = 0.05). The risk of intervention or replacement for branch pulmonary artery stenosis was similar for JVV and allograft. Smaller conduit z-score predicted poor conduit performance (p < 0.01) with best outcome between +1 and +3. Although JVV conduits were a uniform diameter, their z-score more consistently matched this ideal. JVV exhibited a non-significant trend towards slower progression of conduit regurgitation and peak right ventricular outflow tract (RVOT) gradient. In addition, catheter intervention was more successful at slowing subsequent gradient progression in children with JVV versus those with allograft (p < 0.01). Conclusions: JVV does match allograft performance and may be advantageous. It is an appropriate first choice for repair of truncus arteriosus, and perhaps other small infants requiring RVOT reconstruction.     

Inhaled iloprost to control residual pulmonary hypertension following pulmonary endarterectomy

Objective: Pulmonary endarterectomy (PEA) is the standard therapy for patients with chronic thromboembolic pulmonary hypertension (CTEPH). In the immediate postoperative period, persistent pulmonary hypertension increases the risk of acute respiratory or right heart failure. In pulmonary arterial hypertension, prostanoid inhalation has been found to improve pulmonary hemodynamics, right ventricular function, gas exchange, and clinical outcome. We report the results of a double-blinded randomized trial with the aerosolized prostacyclin analogue iloprost in patients with residual pulmonary hypertension after PEA. Methods: Twenty-two patients (age, 55 ± 13 years; 8 females; propofol- and sufentanil-based anesthesia; pressure-controlled mechanical ventilation) were randomized to receive either a single dose of 25 μg aerosolized iloprost (iloprost group; n = 11) or normal saline (placebo group; n = 11) immediately after postoperative ICU admission. Primary endpoints were changes in gas exchange, pulmonary and systemic hemodynamics, and clinical outcome. Results: Iloprost significantly enhanced cardiac index (CI) and reduced mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance [PVR (dyn s cm⁻⁵)] in contrast to placebo. Placebo: pre-inhalation 413 ± 195 versus post-inhalation 404 ± 196 at 30 min (p = 0.051), 415 ± 189 at 90 min (p = 0.929). Iloprost: pre-inhalation 503 ± 238 versus post-inhalation 328 ± 215 at 30 min (p = 0.001), 353 ± 156 at 90 min (p = 0.003). Blood oxygenation remained unchanged. Conclusion: In addition to the effect of PEA, iloprost reduces residual postoperative pulmonary hypertension, decreases right ventricular afterload and may facilitate the early postoperative management after PEA.     

Fate of pulmonary arteries following Norwood Procedure

Objective: This study evaluated the requirement for surgical reoperation and catheter-based reintervention to central pulmonary arteries (CPAs) following Norwood Procedure (NP). We sought to identify the influence of various surgical techniques employed during NP on subsequent interventions. Methods: Between 1993 and 2004, 226 patients underwent Stage II following NP. Ninety-eight patients (43%) had completion of Fontan circulation (Stage III) and a further 107 (47%) are on course for Fontan completion with 21 (9%) inter-stage deaths. During NP, the aortic arch was reconstructed without additional material (n = 91, 40%) or with a pulmonary homograft patch (n = 135, 60%). Pulmonary blood flow was supplied by modified Blalock–Taussig shunt (n = 177, 78%) or right ventricle to pulmonary artery conduit (RV-PA; n = 49, 22%). The CPAs defect was closed directly (n = 69, 31%) or with a patch (n = 157, 69%). Complete resection of coarctation was performed in 126 patients (56%). Results: Ninety-seven patients (43%) required surgical reoperation to CPAs during Stage II. Actuarial freedom from reoperation was 60 ± 3%, 52 ± 4% and 50 ± 4% at 1, 5 and 10 years, respectively. On multivariable analysis, NP with RV-PA increased risk of reoperation (LR 8.3, 5.3–13.2; p < 0.001). Forty-one patients (18%) required catheter-based reintervention on CPAs. Actuarial freedom from reintervention was 98 ± 1%, 72 ± 4% and 58 ± 6% at 1, 5 and 10 years, respectively. CPA problems were almost exclusively limited to the proximal Left pulmonary artery. On multivariable analysis, catheter-based reintervention became more common with time. Complete resection of coarctation increased risk of reintervention (LR 3.9, 1.6–9.6; p < 0.005). Arch reconstruction and CPAs repair techniques did not affect risk of reoperation or reintervention on CPAs. Conclusions: CPA stenoses and hypoplasia need surgical attention in approximately half of all patients undergoing the NP. The need for reoperation is increased when using the RV-PA conduit technique (although the majority of these are performed as part of the Stage II procedure). Catheter reinterventions are almost exclusively confined to the left CPA and are increased when the arch is shortened by resection of the coarctation tissue at time of NP.     

Long-term experiences on cardiac retransplantation in adults

Background: It remains disputed whether cardiac retransplantation should be performed. This study aimed to evaluate our long-term experiences on cardiac retransplantation in adults. Patients and methods: Between March 1989 and December 2004, 2% (28/1290) of cardiac retransplantations were performed. Results: The reasons for cardiac retransplantation were cardiac allograft vasculopathy (n = 13; 47%), primary graft failure (n = 11; 39%), and refractory acute rejection (n = 4; 14%). The 30-day mortality risk was 29% (acute rejection: 50%; primary graft failure: 36%; cardiac allograft vasculopathy: 15%, p = 0.324), compared to 8.5% for primary cardiac transplantation (p < 0.001). The causes of early death were acute rejection (n = 3; 37%), multiorgan failure (n = 3; 37%), primary graft failure (n = 1; 13%), and right ventricular failure (n = 1; 13%). The late mortality rate was 96/1000 patient-years. The causes of late death were acute rejection (n = 4; 50%), cardiac allograft vasculopathy (n = 2; 25%), multiorgan failure (n = 1; 13%), and infection (n = 1; 13%). The 1-, 5-, 10-, and 15-year survival was respectively 78, 68, 54, and 38% (primary cardiac transplantation), and 46, 41, 32, and 32% (cardiac retransplantation) (p = 0.003). The short-term survival for cardiac retransplantation due to cardiac allograft vasculopathy was likely better than primary graft failure and refractory acute rejection (p = 0.09). Conclusion: The overall outcomes of cardiac retransplantation are significantly inferior to primary cardiac transplantation. Cardiac retransplantation should be only performed for selected patients.     

Pretreatment with recombined human erythropoietin attenuates ischemia–reperfusion-induced lung injury in rats

Objective: Based on the findings that erythropoietin (EPO) has been proved to be a multiple functional cytokine to attenuate ischemia–reperfusion (I/R) injury in various organs such as brain, heart, and kidney in animals, this experiment was designed to evaluate the effect of pretreatment with recombined human erythropoietin (rhEPO) on I/R-induced lung injury. Methods: Left lungs of rats underwent 90 min of ischemia and then were reperfused for up to 2 h. Animals were randomly divided into three experimental groups as sham group, I/R group, and rhEPO + I/R group (a single dose of rhEPO was injected intraperitoneally 3000 U/kg 24 h prior to operation). Lung injury was evaluated according to semi-quantitive analysis of microscopic changes, tissue polymorphonuclear neutrophils (PMNs) accumulation (myeloperoxidase (MPO) activity), and pulmonary microvascular permeability (Evan's blue dying method). Peripheral arterial and venous blood samples were obtained for blood–gas analysis after 5 min occlusion of right lung hilus at the end of reperfusion. The serum concentration of tumor necrosis factor (TNF)- was also measured by the method of enzyme-linked immunosorbent assay. Results: Histological injury scoring revealed significantly lessened lung alveolus edema and neutrophils infiltration in the rhEPO pretreated group compared with I/R group (p < 0.05). The rhEPO pretreated animals exhibited markedly decreased lung microvascular permeability (p < 0.05) and myeloperoxidase activity (p < 0.05). Blood–gas analysis demonstrated that the pretreated animals had significantly ameliorated pulmonary oxygenation function (p < 0.05). The serum concentration of tumor necrosis factor- in rhEPO pretreated group was markedly decreased compared with that of I/R group (p < 0.05). Conclusions: Pretreatment with rhEPO appears to attenuate I/R-induced lung injury. This function is partly related with the capacity that rhEPO inhibits the accumulation of polymorphonuclear neutrophils in lung tissue and decreases the systematic expression of tumor necrosis factor-.     

Factors affecting early and long-term outcomes after completion pneumonectomy

Objective: To identify factors that affect operative mortality and morbidity and long-term survival after completion pneumonectomy. Methods: We retrospectively reviewed the charts of consecutive patients who underwent completion pneumonectomy at our cardiothoracic surgery department from January 1996 to December 2005. Results: We identified 69 patients, who accounted for 17.8% of all pneumonectomies during the study period; 22 had benign disease and 47 malignant disease (second primary lung cancer, n = 19; local recurrence, n = 17; or metastasis, n = 11). There were 50 males and 19 females with a mean age of 60 years (range, 29–80 years). Postoperative mortality was 12% and postoperative morbidity 41%. Factors associated with postoperative mortality included obesity (p = 0.005), coronary artery disease (p = 0.03), removal of the right lung (p = 0.02), advanced age (p = 0.02), and renal failure (p < 0.0001). Preoperative renal failure was the only significant risk factor for mortality by multivariate analysis (p = 0.036). Bronchopleural fistula developed in seven patients (10%), with risk factors being removal of the right lung (p = 0.04) and mechanical stump closure (p = 0.03). Overall survival was 65% after 3 years and 46% after 5 years. Long-term survival was not affected by the reason for completion pneumonectomy. Conclusion: Although long-term survival was acceptable, postoperative mortality and morbidity rates remained high, confirming the reputation of completion pneumonectomy as a challenging procedure. Significant comorbidities and removal of the right lung were the main risk factors for postoperative mortality. Improved patient selection and better management of preoperative renal failure may improve the postoperative outcomes of this procedure, which offers a chance for prolonged survival.     

A three decade analysis of factors affecting burn mortality in the elderly

This study's objective was to identify variables that affect the mortality of elderly burn patients and to assess their changes over time. A retrospective review was conducted on all patients 75 or older (n = 201) admitted to a university-based burn center between 1972 and 2000. Variables examined were age, sex, TBSA, ABSI, inhalation injury, timing from burn to operative intervention, the number of surgical procedures, the number of pre-morbid conditions, and mortality. There were 95 fatalities. TBSA strongly correlated with mortality (p < 0.0001). Adjusting for TBSA and inhalation injury, mortality significantly decreased (p = 0.04, odds ratio = 0.58). Mortality significantly increased with inhalation injury (p < 0.01). Fatality risk increased by 400% with inhalation injury. Absence of inhalation injury was not significant with respect to mortality in the 1970s, however there was a significant decrease (p = 0.02) in mortality without an inhalation injury in the 1980s and 1990s. ABSI was strongly predictive of mortality (p < 0.0001). On average there was a 200% increase in mortality per unit increase of ABSI. The elderly are 58% less likely to die from burns now as compared to the 1970s. Although mortality rose with increasing TBSA equally in each decade, the absolute risk of mortality decreased over time. This data suggests major strides have been made in burn care, however similar success has not been achieved with inhalation injuries.     

Clinical advantages of using mini-bypass systems in terms of blood product use, postoperative bleeding and air entrainment: an in vivo clinical perspective

Objective: In an effort to minimize the effect of extracorporeal circulation (ECC), mini-bypass is gaining clinical acceptance in routine coronary artery bypass grafting (CABG). These small circuits target combine the clinical advantages of reduced prime, 100% bio-coating and suction blood separation. We demonstrate that the use of mini-bypass in routine CABG reduces homologous blood product use and postoperative bleeding. Our goal was to also demonstrate that these small systems are effective in gaseous microemboli (GME) management as compared to a conventional extracorporeal system. Methods: Prospective, randomized study comparing 30 mini-bypass (Dideco ECC.O™) to 30 conventional systems (n = 30, Dideco 903 Avant™). Study included CABG cases only, independent of preoperative coagulative status; clinic ethical committee approval and informed patient consent was obtained before initiating study. Results: There were no statistical differences in terms of patient demographics. Statistically significant differences were seen in transfusion frequency (27% of the study group vs 43% in the control group, p = 0.05), transfused volume (133.3 ± 244.5 ml vs 325 ± 483.1 ml, p < 0.05), fresh frozen plasma (0 unit vs 3 units, p < 0.001), postoperative bleeding (301.8 ± 531.9 ml vs 785.5 ± 1000.4 ml, p < 0.05) and GME activity post-arterial filter (0.14 μl vs 5.32 μl, p < 0.05). Conclusions: The adoption of mini-bypass significantly potentially reduces hemodilution, donor blood usage, postoperative bleeding and exposure to GME in routine CABG patients as compared to the use of conventional extracorporeal circulation circuits.     

Preliminary experience with inhaled milrinone in cardiac surgery

Background: Inhaled administration of milrinone reduces pulmonary artery pressure. Pulmonary hypertension (PH) and right heart failure are associated with difficult separation from cardiopulmonary bypass (CPB). Therefore, inhaled milrinone could facilitate separation from CPB. Objective: To determine the impact and timing of administration of inhaled milrinone. Methods: A retrospective analysis of our experience on high-risk patients receiving inhaled milrinone was conducted to evaluate the postoperative course after administration of the drug. Results: Seventy-three patients received inhaled milrinone from June 2002 to February 2005. Mean age was 64 ± 13 years, with a mean preoperative Parsonnet score of 27 ± 14. Inhaled milrinone (5 mg) was administered before (n = 30) or after (n = 40) CPB, three patients had off-pump procedures and were excluded. CPB time was 145 ± 78 min with cross-clamping times of 91 ± 56 min without any significant difference between groups. Fifty-four patients (74%) had difficult separation from CPB, 14 patients (19%) required an intra-aortic balloon pump and 10 patients (14%) needed emergency reinitiation of CPB for hemodynamic instability. Ten patients died in the perioperative period (13.7%). Patients receiving inhaled milrinone prior to CPB initiation had a lowering pulmonary artery pressure after CPB (p < .01) and had less emergency reinitiation of CPB after weaning (3% vs 23%, p = .02) as compared to those with administration after CPB. No detectable side effects were directly linked to the administration of the drug. Conclusion: In this high-risk cohort, use of inhaled milrinone was well tolerated. Administration before initiation of CPB could help weaning from CPB.     

Post-transplant diabetes mellitus in lung transplant recipients: incidence and risk factors

Objective: Post-transplant diabetes mellitus (PTDM) is a common and potentially serious complication after solid organ transplantation. There are only a few data, however, about the incidence of DM in patients undergoing lung transplantation. Patients and methods: The medical records of 119 consecutive patients who underwent lung transplantation from 1998 to September 2004 were reviewed. Patients were divided in three groups according to their diabetes status, including pre-transplant DM, the PTDM group and those without DM. Patient records and all laboratory data were reviewed and the clinical course of diabetes was monitored. All recipients were treated with tacrolimus based regimen. Results: Mean follow-up for all patients was 25 ± 10. Twenty-three patients had DM in the pre-lung transplantation (LTX) DM group. PTDM developed in 34 of the remaining 96 patients (35.4%) with an incidence of 20%, 23% after 6 months and 12 months post-transplant. No significant difference was noted between 12 and 24 months post-LTX. The patients who developed DM were older (57 ± 15 vs 53 ± 13 years, p = 0.009), had increased BMI (26 ± 5 vs 24 ± 4, p = 0.0001), shorter time from diagnosis to LTX (21 ± 13 vs 28 ± 18 months, p = 0.007) more cytomegalovirus infection and more acute rejection and hyperglycemia in the first month after LTX. Four patients died in the PTDM group compared to nine patients in the no-DM group (12% vs 14%; p = 0.72). Conclusions: Post-transplant diabetes is a common complication in lung transplant patients receiving tacrolimus-based immunosuppression. The risk for developing PTDM is greatest among older recipients, those obese, and among recipients with more rejections episodes.     

Retrograde flush following topical cooling is superior to preserve the non-heart-beating donor lung

Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex^® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm⁻⁵) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH₂O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH₂O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion.     

Mitral valve repair by Alfieri''s technique does not limit exercise tolerance more than Carpentier''s correction

Objective: The main goal of this study was to evaluate if the edge-to-edge mitral repair could be a limiting factor for exercise tolerance and to compare these results to those of classical techniques. Methods: Between 2000 and 2002, 54 consecutive patients were operated on for mitral valve regurgitation (MR). Twenty-five patients were operated with Alfieri's technique (group A) and 29 patients with Carpentier's technique (group C). The mean age was 63.9 years in group A and 63.8 years in group C (p = 0.98). After a mean follow-up of 16.2 ± 12 months, survivor patients were seen at the outpatient clinic, by the same physician for a clinical evaluation, an echocardiogram at rest and at peak exercise, and received a cardiorespiratory exercise testing with maximal oxygen uptake (VO₂ max) recording. Results: Clinical status improved with 0% of the patients in class NYHA III or IV in either group postoperatively versus 77% preoperatively. There was no significant MR in 80% of cases in group A versus 89.6% in group C (p = 0.54). The mean mitral valve area was 2.5 and 2.9 cm² in groups A and C, respectively (p = 0.018). The mitral gradient at rest was 3.8 and 3.3 mmHg (p = 0.31) and the mitral gradient at peak exercise was 8.5 and 9.7 mmHg (p = 0.22) in groups A and C, respectively. Cardiorespiratory exercise testing showed a mean VO₂ max of 73.7 ± 15% of normal value in group A versus 79.6 ± 13.1% in group C (p = 0.18). Conclusion: Alfieri's technique has the same efficiency on improvement of MR and clinical status than classical repair. Despite a higher restriction of mitral valve area at rest in group A, gradient and mean VO₂ max at peak exercise were similar in both groups.     

Persistent vegetative state in electrical injuries: a 10-year review

We reviewed 148 cases of electrical injury admitted to our burn centre. The incidence of persistent vegetative state was 3% (n = 5), higher in the low-voltage (6.7%) than in high-voltage group (1.2%). At the time of trauma, 44% (n = 65) lost consciousness and 50% of these (n = 32) received cardiopulmonary resuscitation on arrival at hospital. Of these, 50% recovered (n = 16), 22% became comatose (n = 7) and 28% (n = 9) died. Of the seven comatose patients, five did not show brain oedema but remained in a persistent vegetative state; this state was more common with low-voltage electrical injuries. The public should be warned of this effect of low-voltage trauma.     

Comparison of on pump and off pump coronary surgery: risk factors for neurological outcome

Objective: Cerebrovascular accidents (CVA) are devastating complications after coronary artery bypass grafting (CABG). The reported incidence of neurological complications after conventional CABG (CCABG) is 3–6%. Off-pump coronary bypass grafting (OPCAB) has been associated in recent studies to a decreased morbidity and risk of perioperative stroke. Nevertheless, uncertainty still surrounds the relative benefits of OPCAB. We investigated whether, in our experience, OPCAB was associated with lower neurological morbidity than conventional CABG approach. Methods: Eight thousand and two patients underwent isolated CABG at our institution between January 1998 and January 2005. OPCAB operation was performed on 1415 patients. Data were prospectively collected. A multiple logistic regression analysis was used to evaluate the influence of the two different surgical techniques on the neurological outcomes. Results: Patients in the OPCAB group were significantly older (66.2 vs 63.5%, p < 0.0001), had a higher incidence of renal injury (5.4 vs 2.4%, p < 0.0001), and were more redo interventions (6.95 vs 1.53%, p < 0.0001). The CCABG patients were more urgent at operation (5.46 vs 3.26, p = 0.0007), were less hypertensive (57.6 vs 63% of the patients, p = 0.0003) more diabetics (22 vs 20.6%, NS), and had an ejection fraction less than 0.40 (10.4 vs 9.6%, NS). CVA incidence was similar in both groups (Type I outcome: OPCAB = 0.70% vs CCABG = 0.68%, p = 0.91; Type II outcome OPCAB = 0.70% vs CCABG = 0.83%, p = 0.63). Conclusions: In our experience patients undergoing CCABG were not exposed to a grater risk of neurological adverse events when compared to OPCAB patients.     

Impact of HIV Infection on Total Body Composition in Treatment—Naive Men Evaluated by Dual-Energy X-ray Absorptiometry Comparison of 90 Untreated HIV-Infected Men to 241 Controls

The aim of this study was to establish the contribution of human immunodeficiency virus (HIV) itself on body composition changes evaluated by dual-energy X-ray absorptiometry (DXA). Body composition evaluated by DXA in 90 HIV never treated men, without comorbidity, or current or past opportunistic infections were compared with 241 healthy volunteers. The mean duration of seropositivity from HIV diagnosis was 41 ± 62 mo, mean CD4 and viral load at the time of DXA were 402/mm³ ± 263 (control values 500–1200/mm³) and 4.2 log copies/mL ± 1.3. Mean age (41 vs 39 yr, respectively, for HIV never treated patients and controls) and mean height (174.5 vs 176 cm) were not different, but mean weight was lower among HIV never treated patients (69.8 vs 78.7 kg). Mean total body bone mineral density (BMD) of naive HIV-infected patients was lower than that of controls (1.20 vs 1.23 g/cm², p = 0.01) but not after adjustment on age, height, lean mass (LM), and fat mass ratio (FMR = % trunk fat mass/% lower limb fat mass). Fat mass (13.2 vs 16.5 kg, p < 0.0001) and LM (53.5 vs 59 kg, p < 0.0001) of naive HIV-infected patients were lower whatever the adjustment variables. The FMR was lower in naive HIV-infected men (1.0 vs 1.3, p < 0.0001) because of a decreased trunk fat mass. After adjustment on age, height, LM, and fat mass, the lower limbs fat mass percentage was higher in HIV-infected men. The profile of naïve HIV-infected patients displayed low lean and fat masses, and a fat mass repartition characterized by a predominant loss in the trunk. Those alterations may result from the catabolic effect of the chronic HIV infection.     

Effects of hyperbaric oxygen therapy on fibrovascular ingrowth in porous polyethylene blocks implanted under burn scar tissue: an experimental study

Effects of hyperbaric oxygen (HBO) therapy on biointegration of porous polyethylene (PP) implanted beneath dorsal burn scar and normal skin were experimentally examined in Sprague–Dawley rats. In Group One (n = 20), daily HBO treatments were given after the implantation of PP material under dorsal burn scar, whereas, in Group Two (n = 20) no treatment was given following the same surgical procedure. In Group Three (n = 20), PP was placed under dorsal normal skin and subsequently HBO therapy protocol was applied while Group Four (n = 20) stayed without HBO treatment after the implantation. One, 2, 3 and 4 weeks after the implantations, sections were respectively taken from five rats from each group. Biointegration process and effects of HBO therapy were evaluated microscopically and the ratio of fibrovascular ingrowth (FVI) was determined for each rat. The results showed significantly superior FVI in Group One compared to Group Two and again FVI into PP under normal skin treated with HBO revealed better results against Group Four (p < 0.05). Well-vascularized capsule formation and tissue integration was delayed both in Group Two and in Group Three in the first 3 weeks. In conclusion, HBO therapy enhances biointegration of PP in hypoxic burn scar areas via improving collagen synthesis and neovascularization; otherwise, it apparently delays tissue ingrowth into porous structure implanted in normal healthy tissues.     

Risk factors for reoperation after relief of congenital subaortic stenosis

Background: Congenital subaortic stenosis entails a lesion spectrum, ranging from an isolated obstructive membrane, to complex tunnel narrowing of the left outflow associated with other cardiac defects. We review our experience with this anomaly, and analyze risk factors leading to restenosis requiring reoperation. Methods: From 1994 to 2006, 58 children (median age 4.3 years, range 7 days–13.7 years) underwent primary relief of subaortic stenosis. Patients were divided into simple lesions (n = 43) or complex stenosis (n = 15) associated with other major cardiac defects. Age, pre- and postoperative gradient over the left outflow, associated aortic or mitral valve insufficiency, chromosomal anomalies, arteria lusoria, and operative technique (membrane resection (22) vs associated myectomy (34) vs Konno (2)) were analyzed as risk factors for reoperation (Kaplan–Meier, Cox regression). Results: There was no operative mortality. Median follow-up spanned 2.7 years (range 0.1–10), with one late death at 4 months. Reoperation was required for recurrent stenosis in 11 patients (19%) at 2.6 years (range 0.3–7.5) after initial surgery. Risk factors for reoperation included complex subaortic stenosis (p = 0.003), younger age (p = 0.012), postoperative residual gradient (p = 0.019), and the presence of an arteria lusoria (p = 0.014). For simple lesions, no variable achieved significance for stenosis recurrence. Conclusions: Surgical relief of congenital subaortic stenosis, even with complex defects, yields excellent results. Reoperation is not infrequent, and should be anticipated with younger age at operation, complex defects, residual postoperative gradient, and an arteria lusoria. Myectomy concomitant to membrane resection, even in simple lesions, does not provide enhanced freedom from reoperation, and should be tailored to anatomic findings.     

Effect of Ascites on Bone Density Measurement in Cirrhosis

Cirrhosis is an independent risk factor for the development of osteoporosis. The presence of ascites in patients with cirrhosis may affect the accuracy of bone density measurement in the spine. Twenty cirrhotic patients had bone mineral density (BMD) measurements of the lumbar spine, femoral neck, hip, and total body using dual-energy X-ray absorptiometry (DXA; Lunar Prodigy) before and after large-volume paracentesis. To establish short-term precision of DXA measurement, 28 healthy adults also had duplicate BMD measurements on the same day. After paracentesis (6.4 ± 2.0 L), there was a significant increase in the spine BMD of 4.2% (p = 0.003) and in the total hip BMD of 1.3% (p = 0.002), but there was no change in the femoral neck or total body. No significant differences (p > 0.1) were seen in duplicate BMD measurements at any site among the healthy cohort. Within-patient changes in spine (p = 0.001) and total hip (p = 0.001) BMD measurements were significantly greater in patients with ascites than in the healthy cohort. These changes in BMD measurements were not associated with age, gender, amount of fluid removed, or time interval between measurements. These results suggest that ascites cause a fluid artifact in the soft tissue and bone interface that can falsely lower BMD measurements, particularly in the spine.