Early Progressive Mobilization of Patients with External Ventricular Drains: Safety and Feasibility.

BACKGROUND/OBJECTIVE: Early mobilization of critically ill patients has been shown to improve functional outcomes. Neurosurgery patients with an external ventricular drain (EVD) due to increased intracranial pressure often remain on bed rest while EVD remains in place. The prevalence of mobilizing patients with EVD has not been described, and the literature regarding the safety and feasibility of mobilizing patients with EVDs is limited. The aim of our study was to describe the outcomes and adverse events of the first mobilization attempt in neurosurgery patients with EVD who participated in early functional mobilization with physical therapy or occupational therapy. METHODS: We performed a single-site, retrospective chart review of 153 patients who underwent placement of an EVD. Hemodynamically stable patients deemed appropriate for mobilization by physical or occupational therapy were included. Mobilization and activity details were recorded. RESULTS: The most common principal diagnoses were subarachnoid hemorrhage (61.4%) and intracerebral hemorrhage (17.0%) requiring EVD for symptomatic hydrocephalus. A total of 117 patients were mobilized (76.5%), and the median time to first mobilization after EVD placement in this group of 117 patients was 38 h. Decreased level of consciousness was the most common reason for lack of mobilization. The highest level of mobility on the patient's first attempt was ambulation (43.6%), followed by sitting on the side of the bed (30.8%), transferring to a bedside chair (17.1%), and standing up from the side of the bed (8.5%). No major safety events, such as EVD dislodgment, occurred in any patient. Transient adverse events with mobilization were infrequent at 6.9% and had no permanent neurological sequelae and were mostly headache, nausea, and transient diastolic blood pressure elevation. CONCLUSION: Early progressive mobilization of neurosurgical intensive care unit patients with external ventricular drains appears safe and feasible.

Role of Intrinsic (Graft) Versus Extrinsic (Host) Factors in the Growth of Transplanted Organs Following Allogeneic and Xenogeneic Transplantation.

In our studies of life-supporting α-1,3-galactocyltransferase knockout (GalT-KO) pig-to-baboon kidneys, we found that some recipients developed increased serum creatinine with growth of the grafts, without histological or immunological evidence of rejection. We hypothesized that the rapid growth of orthotopic pig grafts in smaller baboon recipients may have led to deterioration of organ function. To test this hypothesis for both kidneys and lungs, we assessed whether the growth of outbred (Yorkshire) organ transplants in miniature swine was regulated by intrinsic (graft) or extrinsic (host environment) factors. Yorkshire kidneys exhibited persistent growth in miniature swine, reaching 3.7 times their initial volume over 3 mo versus 1.2 times for miniature swine kidneys over the same time period. Similar rapid early growth of lung allografts was observed and, in this case, led to organ dysfunction. For xenograft kidneys, a review of our results suggests that there is a threshold for kidney graft volume of 25 cm3 /kg of recipient body weight at which cortical ischemia is induced in transplanted GalT-KO kidneys in baboons. These results suggest that intrinsic factors are responsible, at least in part, for growth of donor organs and that this property should be taken into consideration for growth-curve-mismatched transplants, especially for life-supporting organs transplanted into a limited recipient space.

[Heart rate variability: analysis of time-domain indices in patients with chronic Chagas disease before and after an exercise program]. / Variabilidade da frequência cardíaca: análise dos índices no domínio do tempo em portadores de cardiopatia chagásica crónica, antes e após um programa de exercícios.

UNLABELLED: Chagas disease (CD) is an infection caused by the protozoan flagellate Trypanosoma cruzi, and transmitted by insects of the genera Triatoma, Rhodnius and Panstrongylus. The heart is affected to varying degrees by inflammatory and destructive lesions in atrial and ventricular myocardial fibers. Several studies have demonstrated the benefits of exercise in patients with congestive heart failure (CHF), including reduced sympathetic tone and increased parasympathetic tone, the result of reduced epinephrine and norepinephrine levels, both at rest and during exercise, including at submaximal levels. It has been hypothesized that the increase in sympathetic arousal during exercise improves peripheral muscle metabolism. OBJECTIVES: The objectives of this study were to select patients with chronic Chagas cardiomyopathy (CCC) with dysautonomia on 24-h Holter monitoring, assess autonomic function after rehabilitation, and determine whether it resulted in reduced daytime levels of SDNN and increased daytime and nighttime levels of pNN50 and rMSSD. METHODS: We analyzed time-domain indices of heart rate variability through 24-h Holter monitoring before and after a supervised exercise program. We studied 18 CCC patients (five men), mean age 57.33±9.73 years, followed at the CD outpatient clinic of the National Institute of Cardiology and IPEC/Fiocruz in Rio de Janeiro, Brazil, between April 2009 and November 2010. The following tests were used to assess the severity of CCC: clinical examination, functional evaluation by cardiopulmonary stress testing, electrocardiogram and conventional Doppler echocardiography. The exams were performed within a month of the start and end of the exercise program, which consisted of 60-min sessions of aerobic exercise on a treadmill and resistance training three times a week for six months. The goal was to reach the patients' heart rate target zone during training, and their rating of perceived exertion was assessed by the modified Borg scale. RESULTS: There were no statistically significant differences (p>0.05) in SDNN, pNN50 and rMSSD, probably due to the large standard deviation observed, patients' poor adherence to the program and their low socioeconomic status, resulting in a small sample, and the short duration of the program. CONCLUSION: Heart rate variability parameters in patients with CCC did not undergo statistically significant changes after a six-month cardiac rehabilitation program.

Pre-operative sildenafil and pulmonary endothelial-related complications following cardiopulmonary bypass: a randomised trial in children undergoing cardiac surgery.

In a randomised trial, we compared the effects of oral sildenafil (0.5 mg.kg(-1) ) and placebo, administered the day before cardiac surgery, in 24 children. In sildenafil vs placebo patients, pre-cardiopulmonary bypass median (IQR [range]) cyclic-guanosine-monophosphate was not significantly different (29.9 (2.1-208.1 [0.5-391.5]) vs 5.2 (0.3-54.6 [0-628.9]) pmol.ml(-1) , respectively). Post-cardiopulmonary bypass, nitrate/nitrite levels were also not significantly different (0.7 (0-8.0 [0-142.8]) vs 0 (0-2.7 [0-52.7]) µM, respectively). Postoperatively, mean (SD) pulmonary vascular resistance (2.64 (2.28) vs 1.90 (1.12) WU.m(-2) , respectively and oxygenation index (5.29 (4.60) vs 3.38 (2.54), respectively) remained unchanged, whilst oxygen delivery (57.18 (21.24) vs 74.13 (35.46) ml.min(-1) .m(-2) , respectively) and bi-ventricular systolic function (left ventricle 3.78 (0.94) vs 4.55 (1.08) cm.s(-1) , respectively; p=0.002; right ventricle 6.93 (1.47) vs 8.09 (2.25) cm.s(-1) , respectively; p<0.001) were significantly reduced in the sildenafil group. In this trial, pre-operative sildenafil did not affect postoperative pulmonary vascular resistance. There was, however, a negative impact on ventricular function and oxygenation.

Fibrinogen deficiency is compatible with the development of atherosclerosis in mice.

A critical role of the coagulation system in the development of atherosclerosis has been frequently postulated based on a variety of indirect observations, including the expression of procoagulants and fibrinolytic factors within atherosclerotic vessels, the presence of substantial amounts of fibrin(ogen) and fibrin degradation products within intimal lesions, the cellular infiltration and assimilation of mural thrombi into developing plaques, and the identification of high plasma fibrinogen (Fib) levels as an independent risk factor for the development of ischemic heart disease. To directly examine the role of fibrin(ogen) in atherogenesis, Fib-deficient mice were crossed to atherosclerosis-prone apolipoprotein E (apo E)-deficient mice. Both apo E-/- and apo E-/-/Fib-/- mice developed lesions throughout the entire aortic tree, ranging in appearance from simple fatty streaks to complex fibrous plaques. Furthermore, remarkably little difference in lesion size and complexity was observed within the aortae of age- and gender-matched apo E-/- and apo E-/-/Fib-/- mice. These results indicate that the contribution of fibrin(ogen) to intimal mass and local cell adhesion, migration, and proliferation is not strictly required for the development of advanced atherosclerotic disease in mice with a severe defect in lipid metabolism.

Modified Glenn connection for acutely ischemic right ventricular failure reverses secondary left ventricular dysfunction.

BACKGROUND: Right heart failure after cardiopulmonary bypass can result in severe hemodynamic compromise with high mortality, but the underlying mechanisms remain poorly understood. After ischemia-induced right ventricular failure, alterations in the interventricular septal position decrease left ventricular compliance and limit filling but may also distort left ventricular geometry and compromise contractility and relaxation. This study investigated the effect of acute isolated right ventricular ischemia on biventricular performance and interaction and the response of subsequent right ventricular unloading by use of a modified Glenn shunt. METHODS: In 8 pigs isolated right ventricular ischemic failure was induced by means of selective coronary ligation. A modified Glenn circuit was then established by a superior vena cava-pulmonary artery connection. Ventricular performance was determined by conductance catheter-derived right ventricular pressure-volume loops and left ventricular pressure-segment length loops. Hemodynamic data at baseline, after right ventricular ischemia, and after institution of the Glenn circuit were obtained during inflow occlusion, and the load-independent contractile indices were derived. RESULTS: Right ventricular free-wall ischemia resulted in acute right ventricular dilation (118 +/- 81 mL vs 169 +/- 70 mL, P =.0008) and impairment of left ventricular contractility indicated by the reduced end-systolic pressure-volume relation slope (50.0 +/- 19 mm Hg/mm vs 18.9 +/- 8 mm Hg/mm, P =.002) and preload recruitable stroke work index slope (69.6 +/- 26 erg x cm(-3) x 10(3) vs 39.7 +/- 13 erg x cm(-3) x 10(3), P =.003). In addition, left ventricular relaxation (tau) was significantly prolonged (33.3 +/- 10 ms vs 53.0 +/- 16 ms, P =.012). Right ventricular unloading with the Glenn shunt reduced right ventricular dilation and significantly improved left ventricular contraction, end-systolic pressure-volume relation slope (18.9 +/- 8 mm Hg/mm vs 35.8 +/- 18 mm Hg/mm, P =.002), preload recruitable stroke work index slope (39.7 +/- 26 erg x cm(-3) x 10(3) vs 63.0 +/- 22 erg x cm(-3) x 10(3), P =.003), and diastolic performance (tau 53.0 +/- 16 ms vs 43.5 +/- 13 ms, P =.001). CONCLUSIONS: Right ventricular ischemia-induced dilation resulted in acute impairment of left ventricular contractility and relaxation. A modified Glenn shunt attenuated the left ventricular dysfunction by limiting right ventricular dilation and restoring left ventricular cavity geometry.

Genetic manipulation of fibrinogen and fibrinolysis in mice.

Vascular integrity is maintained by a sophisticated system of circulating and cell associated hemostatic factors that control local platelet deposition, the conversion of soluble fibrinogen to an insoluble fibrin polymer, and the dissolution of fibrin matrices. However, hemostatic factors are likely to be biologically more important than merely maintaining vascular patency and controlling blood loss. Specific hemostatic factors have been associated with a wide spectrum of physiological processes, including development, reproduction, tissue remodeling, wound repair, angiogenesis, and the inflammatory response. Similarly, it has been proposed that hemostatic factors are important determinants of a variety of pathological processes, including vessel wall disease, tumor dissemination, infectious disease, and inflammatory diseases of the joint, lung, and kidney. The development of gene targeted mice either lacking or expressing modified forms of selected hemostatic factors has provided a valuable opportunity to test prevailing hypotheses regarding the biological roles of key coagulation and fibrinolytic system components in vivo. Genetic analyses of fibrin(ogen) and its interacting factors in transgenic mice have proven to be particularly illuminating, often challenging long standing concepts. This review summarizes the key findings made in recent studies of gene targeted mice with single and combined deficits in fibrinogen and fibrinolytic factors. Studies illustrating the role and interplay of these factors in disease progression are highlighted.

Excimer versus carbon dioxide transmyocardial laser revascularization: effects on regional left ventricular function and perfusion.

BACKGROUND: Transmyocardial laser revascularization (TMR) has been established with the carbon dioxide (CO2) laser. The largely unstudied excimer laser creates channels through chemical bond dissociation instead of thermal ablation, thereby avoiding thermal injury. We sought to compare the effects of CO2 and excimer TMR in a porcine model of chronic ischemia. METHODS: Pigs underwent ameroid constrictor placement on the circumflex artery to create chronic ischemia. TMR was performed with CO2 (n = 8) or excimer (n = 8) laser 6 weeks later; controls (n = 7) had ameroid placement only. Regional myocardial blood flow (RMBF), determined by radioactive microspheres, and regional myocardial function, determined by percent segmental shortening (%SS), were assessed 18 weeks after ameroid placement. RESULTS: Values are mean +/- SD. In the ischemic zone, RMBF (mL/min/g) was improved in the CO2 (0.73 +/- 0.19) and excimer (0.78 +/- 0.22) groups when compared with controls (0.55% +/- 0.12%, p < 0.05). %SS was also improved in the CO2 (15.2% +/- 5.5%) and excimer (15.3% +/- 5.1%) groups when compared with controls (8.0% +/- 4.2%, p < 0.05). CONCLUSIONS: Excimer and CO2 TMR significantly improve RMBF and regional function in this porcine model of chronic myocardial ischemia despite fundamentally different tissue interactions.

Clinical and hemodynamic performance of the Toronto SPV bioprosthesis.

BACKGROUND AND AIM OF THE STUDY: By providing a superior hemodynamic profile, the stentless valve design allows ventricular remodeling and may improve patient survival after aortic valve replacement (AVR). Compared with stent-mounted prostheses, implantation is more complex and requires a longer ischemic time; this may adversely affect surgical risk, especially if patients are elderly or require a concomitant procedure. The mid-term clinical and hemodynamic performance of the Toronto SPV bioprosthesis in a predominantly elderly patient group was analyzed. METHODS: A total of 123 patients (median age 72 years) underwent AVR with the Toronto SPV. Concomitant procedures (mainly coronary artery bypass grafting, CABG), were performed in 60 patients (49%). Clinical details were recorded, with 100% follow up (total 317 patient-years). Hemodynamic evaluation, by serial echocardiography, was performed at four and 18 months after implantation. RESULTS: The early mortality rate was low (0.8%). Mean (+/- SD) actuarial survival at 53 months was 78 +/- 5.9%, with most patients (91%) in NYHA classes I and II. Freedom from valve-related complications were: endocarditis 93.8 +/- 2.3%, thromboembolism 90.3 +/- 3.7% and bleeding 95.8 +/- 1.8%; there were no structural failures. The valve hemodynamic profile was excellent for all sizes: peak gradient 8.8 +/- 4.3 mmHg, effective orifice area 1.9 +/- 0.54 cm2 with significant improvement in left ventricular fractional shortening. CONCLUSION: In this patient population the Toronto SPV was a suitable choice. Advanced age, a requirement for concomitant procedures and increased ischemic times did not adversely affect surgical risk. AVR with the Toronto SPV provided an excellent hemodynamic profile, and improved both left ventricular function and NYHA functional class.

Simultaneous cardiac surgery with pulmonary resection: presentation of series and review of literature.

BACKGROUND: The issue of performing simultaneous pulmonary resection and cardiac surgery in patients with coexisting lung carcinoma and ischaemic heart disease remains controversial. We report our experience and review the literature. METHODS: Thirteen patients (male ten, female three; mean age 65 years) underwent simultaneous cardiac surgery and pulmonary resection. Lung pathology consisted of primary lung carcinoma (n = 10), benign disease (n = 2) and carcinoid (n = 1). Lung resections included pneumonectomy (n = 3), lobectomy (n = 4), segmentectomy (n = 1) and local excision (n = 5). Cardiac procedures consisted of coronary artery bypass grafting (CABG) in 11, aortic valve replacement in one and mitral valve repair with CABG in one patient. In all but one case the lung resection was performed prior to heparinization and cardiopulmonary bypass (CPB). In two patients, with suitable coronary anatomy, myocardial revascularization without CPB was performed to reduce morbidity. RESULTS: There was no hospital mortality. Postoperative blood loss and ventilation requirements were reduced in the patients who were operated on without CPB. Prolonged ventilatory support was required in two cases. All patients with benign pathology are alive. In the lung cancer group there have been five late deaths: disseminated metastatic disease (n = 3), anticoagulant related haemorrhage (n = 1) and broncho-pleural fistula (n = 1). Of the remaining five patients four are alive and disease free 7-23 months post-operatively; one patient has recurrent disease 40 months post-operatively. CONCLUSIONS: Simultaneous pulmonary resection and cardiac surgery is associated with acceptable operative morbidity and mortality. In patients with lung carcinoma long-term survival was determined by tumour stage. The avoidance of CPB may be advantageous by decreasing blood loss and ventilation requirements.

Repair of truncus arteriosus: a considered approach to right ventricular outflow tract reconstruction.

OBJECTIVE: In repair of truncus arteriosus the accepted methods of establishing right ventricle (RV) to pulmonary artery (PA) continuity utilize an allograft or xenograft valved conduit. Alternatively, the PA confluence may be directly anastomosed to the RV with anterior patch augmentation, which may allow growth and delay or avoid subsequent RVOT obstruction. These methods of RVOT reconstruction were evaluated in infants undergoing truncus arteriosus repair. METHODS: A retrospective analysis of 61 infants undergoing repair of truncus arteriosus between November 1988 and June 2000 was performed. Median age was 34 days (range 1 day to 6.4 months). The patient cohort was subdivided into two groups (1) Valved conduit group: RV to PA continuity performed with a conduit in 38 patients using allograft (28) or xenograft (10). (2) Direct anastomosis group: direct RV-PA anastomosis performed in 23 patients, augmented anteriorly with monocusp (15) or simple pericardial patch (eight). RESULTS: There were eight hospital deaths (13%, 95% confidence limits 5--21%). Hospital mortality did not differ significantly between group 1 and 2 (three patients (8%) versus five patients (22%) respectively, P=0.23). By multivariate analysis, low operative weight (P=0.023), severe truncal regurgitation (P=0.022) and major coronary abnormalities (P=0.018), were independent risk factors for hospital death. Hospital survivors were followed-up from 1.3 months to 11.8 years (mean 4.2+/-3.4 years). There were eight late deaths with survival of 73+/-6% at 2 years and beyond. Survival was not influenced by method of RVOT reconstruction (Conduit versus direct RV-PA anastomosis, 2.76+/-7%, 63+/-10%, respectively, P=0.23). Freedom from surgical RVOT reintervention was 56+/-10% in group 1 and 89+/-10% in group 2 at 10 years (P=0.023). The use of a xenograft conduit was an independent risk factor for reintervention (P<0.001). CONCLUSIONS: In truncus arteriosus repair, RV to PA continuity established by a direct anastomosis was associated with a low incidence of surgical RVOT re-intervention. This technique has the potential for RVOT growth and may be a useful alternative when an appropriate allograft is unavailable, particularly in the neonate where the risk of pulmonary hypertension are lower.

Smooth muscle tumours of the alimentary tract.

Neoplasms arising from smooth muscle of the gastrointestinal (GI) tract are uncommon, comprising only 1% of gastrointestinal tumours. A total of 51 cases of smooth muscle tumour of the GI tract were analysed; 44 leiomyomas and 7 leiomyosarcomas. Lesions occurred in all areas from the oesophagus to the rectum, the stomach being the commonest site. Thirty-six patients had clinical features referable to the tumour. The tumour was detected during investigation or management of an unrelated disease process in 15 patients. The clinical presentation varied depending on tumour location, but abdominal pain and GI bleeding were the commonest presenting symptoms. The lesion was demonstrated preoperatively, mainly by endoscopy and barium studies, in 27 patients. Surgical excision was the treatment of choice, where possible. There was no recurrence in the leiomyoma group but four patients died in the leiomyosarcoma group. Although rare, smooth muscle tumours should be considered in situations where clinical presentation and investigations are not suggestive of any common GI disorder. The preoperative assessment and diagnosis is difficult because of the variability in clinical features and their inaccessibility to routine GI investigation. It is recommended that, where possible, the lesion, whether symptomatic or discovered incidentally, should be excised completely to achieve a cure and prevent future complications.

Harderoporphyrin: a misnomer.

More than 30 years ago it was reported that rodent Harderian glands contained a tricarboxylic acid porphyrin, which the authors named Harderoporphyrin. The recent finding in rat Harderian glands of the porphyrin glycoconjugate, protoporphyrin-1-O-acyl-beta-xyloside as a major component led to scrutiny of earlier publications. It became apparent that the results were flawed and that the conclusions were unsustainable. The procedural artefacts which led to the errors are discussed and their bases are demonstrated experimentally. Harderoporphyrin as originally defined never existed.

Isolation of mutant adenosine deaminase by coformycin affinity chromatography.

Adenosine deaminase is a purine salvage enzyme that catalyzes the deamination of adenosine and deoxyadenosine. Deficiency of the enzyme activity is associated with T-cell and B-cell dysfunction. Mutant adenosine deaminase has been isolated from heterozygous and homozygous deficient lymphoblast cell lines with the aid of an affinity matrix consisting of coformycin (a potent inhibitor of the enzyme) as the affinity ligand, bound to 3,3'-iminobispropylamine-derivatized Sepharose. Routinely, 80-90% of adenosine deaminase in crude cell homogenates could be bound to the material. Adenosine deaminase was specifically eluted by enzyme inhibitors or less efficiently by high substrate concentrations. Protein preparations isolated from several different deficient cell lines were highly purified and exhibited molecular weights identical to wild-type adenosine deaminase. This method produces a protein that is suitable for structural studies.

Prophylactic digitalisation in pulmonary surgery.

BACKGROUND: Prophylactic digoxin is widely used in patients undergoing pulmonary surgery to prevent or control cardiac arrhythmias, but whether it is helpful or not is uncertain. METHODS: An open, controlled randomised prospective clinical study of 111 patients was undertaken to compare the incidence of cardiac arrhythmias in the 58 patients who received preoperative digoxin and the 53 who did not. RESULTS: Cardiac arrhythmia occurred in half (29/58) of those given prophylactic digoxin and in 36% (19/53) of those who were not. The overall incidence of arrhythmia was 43%, with no statistically significant difference between the groups. CONCLUSION: Cardiac arrhythmias remain an important complication of pulmonary surgery and the incidence is not reduced by prophylactic digoxin.

[SVCV infection of Carp (author's transl)]. / Virémie printanière de la carpe. Résultats de contaminations expérimentales effectuées au printemps.

This word was carried out to confirm several pathogenical points which had been previously outlined during SVCV infection trials of carp performed in autumn at + 11 degrees C, when the temperature was naturally decreased. Here, 50 g carp which had undergone the wintering, were infected in spring either via the water-route (2 h in 5 x 10(3) pfu/ml water) or intraperitoneally (5 x 10(3) pfu/fish) when the natural elevation of the water temperature had reached + 11 degrees C. Then the fish appeared to be readily susceptible to infection and the course of the disease estimated by the virus detection in gill, blood and water, was 3 to 4 times quicker than that of the autumn infection. The virus detection in gill is the first clue of contamination and the viraemia accounts for the spleen and kidney target cells infection and its increase is fatal.