Improved Accuracy and Sensitivity in Diagnosis and Staging of Lung Cancer with Systematic and Combined Endobronchial and Endoscopic Ultrasound (EBUS-EUS): Experience from a Tertiary Center

BACKGROUND

Combined endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endoscopic ultrasound-guided tissue acquisition (EUS-TA) are accurate procedures for the diagnosis and staging of mediastinal lymph nodes (MLNs) in lung cancer. However, the respective contribution of separate and combined procedures in diagnosis and staging has not been fully studied. The aim of this study was to assess their respective performances.

METHODS

Patients with suspected malignant MLNs in lung cancer or recurrence identified by PET-CT who underwent combined EBUS-TBNA and EUS-TA were retrospectively reviewed.

RESULTS

A total of 141 patients underwent both procedures. Correct diagnosis was obtained in 82% with EBUS-TBNA, 91% with EUS-TA, and 94% with the combined procedure. The overall sensitivity, specificity, and positive and negative predictive values (PPV and NPV) of EBUS-TBNA, EUS-TA, and the combined procedure for diagnosing malignancy were [75%, 100%, 100%, 58%], [87%, 100%, 100%, 75%], and [93%, 100%, 100%, 80%], respectively, with a significantly better sensitivity of the combined procedure (p < 0.0001). Staging (82/141 patients) was correctly assessed in 74% with EBUS-TBNA, 68% with EUS-TA, and 85% with the combined procedure. The overall sensitivity, specificity, PPV, and NPV of EBUS-TBNA, EUS-TA, and the combined procedure for lung cancer staging were [62%, 100%, 100%, 55%], [54%, 100%, 100%, 50%], and [79%, 100%, 100%, 68%], respectively, significantly better in terms of sensitivity for the combined procedure (p < 0.001).

CONCLUSION

The combined EBUS-EUS approach in lung cancer patients showed better accuracy and sensitivity in diagnosis and staging when compared with EBUS-TBNA and EUS-TA alone.

Prostacyclin receptor agonists induce DUSP1 to inhibit pulmonary artery smooth muscle cell proliferation

AIMS

Upregulated p38^MAPK signaling is implicated in the accelerated proliferation of pulmonary artery smooth muscle cells (PA-SMCs) and the pathogenesis of pulmonary artery remodeling observed in pulmonary arterial hypertension (PAH). Previously, we reported that after endothelin-1 (ET-1) pretreatment, bone morphogenetic protein 2 (BMP2) activates p38^MAPK signaling and accelerates PA-SMC proliferation. The activity of p38^MAPK signaling is tightly regulated by the inactivation of dual-specificity phosphatase 1 (DUSP1). Activated p38^MAPK induces DUSP1 expression, forming a negative feedback loop. Prostacyclin IP receptor agonists (prostacyclin and selexipag) are used to treat PAH. In this study, we aimed to verify whether IP receptor agonists affect DUSP1 expression and accelerate the proliferation of PA-SMCs.

MAIN METHODS

PA-SMCs were treated with BMP2, ET-1, prostacyclin, and MRE-269, an active metabolite of selexipag, either alone or in combination. We quantified mRNA expressions using real-time quantitative polymerase chain reaction. Pulmonary artery specimens and PA-SMCs were obtained during lung transplantation in patients with PAH.

KEY FINDINGS

Both prostacyclin and MRE-269 increased DUSP1 expression. Combined treatment with BMP2 and ET-1 induced cyclin D1 and DUSP1 expression and increased PA-SMC proliferation. MRE-269 attenuated BMP2/ET-1-induced cell proliferation. ET-1 increased DUSP1 expression in PA-SMCs from control patients but not in PA-SMCs from patients with PAH.

SIGNIFICANCE

This study showed that the p38^MAPK/DUSP1 negative feedback loop is impaired in PAH, contributing to unregulated p38^MAPK activation and PA-SMC hyperplasia. IP receptor agonist MRE-269 increases DUSP1 expression and inhibit p38^MAPK-mediated PA-SMC proliferation. Future elucidation of the detailed mechanism underlying reduced DUSP1 expression would be informative for PAH treatment.

Endothelin-1 induces lysyl oxidase expression in pulmonary artery smooth muscle cells

The increase in thickening of the arterial wall of pulmonary arterial hypertension (PAH) includes cellular proliferation as well as matrix deposition and interrupted internal elastic lamina (IEL) consisting of a thick homogeneous sheet of elastin. Little is, although, known about the detail of IEL formation in PAH. Endothelin-1 is overexpressed in pulmonary arterioles of PAH. We aimed to examine the expression of genes contributing to IEL formation in pulmonary artery smooth muscle cells (PASMCs) especially focused on lysyl oxidase (LOx), an exreacellular matrix enzyme that catalyzes the cross-linking of collagens or elastin. We quantified mRNA expressions of genes contributing to IEL formation including LOx in PASMCs using real-time quantitative polymerase chain reaction. We stimulated human PASMCs with endothelin-1 with prostacyclin or trapidil. Endothelin-1 significantly increased LOx expression. Prostacyclin and trapidil restored endothelin-1-induced LOx expression to the basal level. Endothelin-1 increased LOx expression strongly in PASMCs from PAH patients compared to those from controls. Trapidil reduced LOx expression only in PASMCs from PAH patients. Overexpressed endothelin-1 in PAH patients can increase expression of LOx and agitate cross-linking of elastin and collagen, resulting in ectopic deposition of these in the vascular media.

Intraspinal Iliac Venous Stent Migration with Lumbar Nerve Root Compression

BACKGROUND

Venous stenting is a common treatment for chronic peripheral venous disease. The most frequent complications caused by this technique are stent misplacement and intracardiac or intravascular stent migration. In this publication, we will describe the first case of an intraspinal stent misplacement leading to lumbar nerve root compression.

CASE DESCRIPTION

Our patient was a 20-year-old woman with a bilateral pulmonary embolism caused by a right common iliac vein thrombosis and a severe compression of the left common iliac vein by the right common iliac artery (May-Thurner or Cockett syndrome). She underwent an endovascular stenting of the left iliac vein. A few days later, she reported some pain in the right L5 radicular and showed signs of hypoesthesia of the left leg and of paresis of the left extensor hallucis longus muscle. A lumbar computed tomography scan showed a stent misplacement into the spinal canal through the left L5 foramen with nerve root compression. She underwent a surgical removal of the stent through a unilateral L5-S1 laminarthrectomy. The postoperative follow-up showed a complete clinical recovery and a control lumbar computed tomography scan confirmed the L5 nerve root decompression.

CONCLUSIONS

The intraspinal misplacement of a venous stent is a rare complication that may cause nerve root injury. It requires a prompt treatment. Surgically removing the stent by a posterior approach seems to be a simple and safe therapeutic option.

Impact of donor lung quality on post-transplant recipient outcome in the Lung Allocation Score era in Eurotransplant - a historical prospective study

The aim of this study was to investigate whether there is an impact of donation rates on the quality of lungs used for transplantation and whether donor lung quality affects post-transplant outcome in the current Lung Allocation Score era. All consecutive adult LTx performed in Eurotransplant (ET) between January 2012 and December 2016 were included (N = 3053). Donors used for LTx in countries with high donation rate were younger (42% vs. 33% ≤45 years, P < 0.0001), were less often smokers (35% vs. 46%, P < 0.0001), had more often clear chest X-rays (82% vs. 72%, P < 0.0001), had better donor oxygenation ratios (20% vs. 26% with PaO₂ /FiO₂  ≤ 300 mmHg, P < 0.0001), and had better lung donor score values (LDS; 28% vs. 17% with LDS = 6, P < 0.0001) compared with donors used for LTx in countries with low donation rate. Survival rates for the groups LDS = 6 and ≥7 at 5 years were 69.7% and 60.9% (P = 0.007). Lung donor quality significantly impacts on long-term patient survival. Countries with a low donation rate are more oriented to using donor lungs with a lesser quality compared to countries with a high donation rate. Instead of further stretching donor eligibility criteria, the full potential of the donor pool should be realized.

Nosocomial outbreak of extended-spectrum β-lactamase-producing Enterobacter cloacae among cardiothoracic surgical patients: causes and consequences

BACKGROUND

Enterobacteriaceae are recognized as leading pathogens of healthcare-associated infections.

AIM

To report the investigation of a nosocomial outbreak of extended-spectrum β-lactamase-producing Enterobacter cloacae affecting cardiothoracic surgery patients in a Belgian academic hospital.

METHODS

Cases were defined based on epidemiological and microbiological investigations, including molecular typing using repetitive element-based polymerase chain reaction and multi-locus sequence typing. Case-control studies followed by field evaluations allowed the identification of a possible reservoir, and the retrospective assessment of human and financial consequences.

FINDINGS

Over a three-month period, 42 patients were infected or colonized by CTX-M-15-producing E. cloacae strains that belonged to the same clonal lineage. Acquisition mainly occurred in the intensive care unit (N = 23) and in the cardiothoracic surgery ward (N = 16). All but one patient had, prior to acquisition, undergone a cardiothoracic surgical procedure, monitored by the same transoesophageal echocardiography (TOE) probe in the operating room. Despite negative microbiological culture results, the exclusion of the suspected probe resulted in rapid termination of the outbreak. Overall, the outbreak was associated with a high mortality rate among infected patients (40%) as well as significant costs (€266,550).

CONCLUSION

The outbreak was indirectly shown to be associated with the contamination of a manually disinfected TOE probe used per-operatively during cardiothoracic surgery procedures, because withdrawal of the putative device led to rapid termination of the outbreak.

Giant true aneurysm of superficial femoral artery in patient with multiple atherosclerotic aneurysms: A case report

True atherosclerotic aneurysms of superficial femoral artery (SFA) are rare and often associated with other peripheral or aortic aneurysms. We report the case of a 84-year-old patient presenting a giant degenerative ruptured aneurysm of the superficial femoral artery. The patient underwent successful aneurysm resection and bypass grafting, with a satisfying long-term follow-up and patency of the graft. The patient was also operated one year before, for a ruptured aneurysm of the abdominal aorta. This case report is rare, because we described a case of patient with multiple atherosclerotic aneurysms, who present, for the second time, a life threating ruptured aneurysm. In this report, we see extreme and rapid evolution of SFA Aneurysm before being symptomatic. Degenerative aneurysms of the lower extremity most commonly involve the popliteal artery, while they are rarely detected in the femoral region (Leon et al., 2008). In this region, aneurysms most frequently involve the common femoral artery (CFA), whereas true aneurysms of the superficial femoral artery (SFA) represent only 15% to 25% of femoral arterial aneurysms [1-5]. Degenerative aneurysms of the SFA display peculiar characteristics (in terms of clinical onset, diagnostic timing, and clinical behavior) so that they differ from other peripheral aneurysms. Because the relative rarity of this location, our case report can be useful to participate to increase the number of reported cases, and define the therapeutic approach for this rare location.

Bosentan reverses the hypoxia-induced downregulation of the bone morphogenetic protein signaling in pulmonary artery smooth muscle cells

AIMS

Pulmonary hypertension (PH) is a common complication of chronic hypoxic lung diseases. Bone morphogenetic protein (BMP) and endothelin-1 signaling pathways have been shown to be altered in hypoxic PH and to play crucial roles in the associated pulmonary artery remodeling. We, therefore, aimed to study the potential link between hypoxia and the alteration of BMP and endothelin-1 signaling observed in pulmonary artery smooth muscle cells (PA-SMCs) in hypoxic PH.

MATERIALS AND METHODS

Human PA-SMCs were treated with hypoxia-mimetic agent cobalt chloride (CoCl2; 100μM), with or without pretreatment with a dual endothelin receptor antagonist bosentan (10μM). Expressions of preproendothelin-1 (PPET1), BMP type 2 receptor (BMPR-2), and one BMP signaling target gene, the inhibitor of DNA binding 1 (ID1) were evaluated by real time quantitative polymerase chain reaction. BMP2-treated PA-SMCs were assessed for Smad1/5/8 signaling activation by Western Blotting.

KEY FINDINGS

Treatment of PA-SMCs with CoCl2 increased PPET1 gene expression, while it did not alter expressions of endothelin converting enzyme, endothelin receptor type A or type B. Hypoxia-mimetic agent CoCl2 decreased the expressions of BMPR-2 and ID1 maximally after 3- and 6-hour treatment respectively, while CoCl2 treatment progressively increased noggin expression. Bosentan pretreatment restored expressions of BMPR-2 and ID1, as well as the activation (by phosphorylation) of Smad1/5/8 signaling induced by BMP2.

SIGNIFICANCE

Hypoxia induces the downregulation of the BMP signaling in PA-SMCs, at least, partly through the endothelin system. In hypoxic PH, increased endothelin-1 production might therefore contribute to the altered BMP signaling and subsequent PA-SMC hyperplasia.

β-Lactam pharmacokinetics during extracorporeal membrane oxygenation therapy: A case-control study

Most adult patients receiving extracorporeal membrane oxygenation (ECMO) require antibiotic therapy, however the pharmacokinetics of β-lactams have not been well studied in these conditions. In this study, data from all patients receiving ECMO support and meropenem (MEM) or piperacillin/tazobactam (TZP) were reviewed. Drug concentrations were measured 2h after the start of a 30-min infusion and just before the subsequent dose. Therapeutic drug monitoring (TDM) results in ECMO patients were matched with those in non-ECMO patients for (i) drug regimen, (ii) renal function, (iii) total body weight, (iv) severity of organ dysfunction and (v) age. Drug concentrations were considered adequate if they remained 4-8× the clinical MIC breakpoint for Pseudomonas aeruginosa for 50% (TZP) or 40% (MEM) of the dosing interval. A total of 41 TDM results (27 MEM; 14 TZP) were obtained in 26 ECMO patients, with 41 matched controls. There were no significant differences in serum concentrations or pharmacokinetic parameters between ECMO and non-ECMO patients, including Vd [0.38 (0.27-0.68) vs. 0.46 (0.33-0.79)L/kg; P=0.37], half-life [2.6 (1.8-4.4) vs. 2.9 (1.7-3.7)h; P=0.96] and clearance [132 (66-200) vs. 141 (93-197)mL/min; P=0.52]. The proportion of insufficient (13/41 vs. 12/41), adequate (15/41 vs. 19/41) and excessive (13/41 vs. 10/41) drug concentrations was similar in ECMO and non-ECMO patients. Achievement of target concentrations of these β-lactams was poor in ECMO and non-ECMO patients. The influence of ECMO on MEM and TZP pharmacokinetics does not appear to be significant.

Downregulated bone morphogenetic protein signaling in nitrofen-induced congenital diaphragmatic hernia

PURPOSE

Bone morphogenetic proteins (BMP) have been shown to play crucial roles in not only lung and heart development, but also in the pathogenesis of pulmonary vascular remodeling in pulmonary hypertension (PH). We therefore hypothesized that BMP signaling could be altered in nitrofen-induced congenital diaphragmatic hernia (CDH) and associated PH.

METHODS

Pregnant rats were exposed to either 100 mg nitrofen or vehicle on embryonic day (E) 9.5. On E17 and E21, fetuses were delivered by cesarean section, killed and checked for left-sided CDH. The tissue was then harvested for pathobiological evaluation.

RESULTS

In nitrofen-induced CDH, pulmonary expressions of BMP4, BMP receptor (BMPR) type 2 and Id1 decreased on E17 and E21. On E17, pulmonary gremlin-1 expression increased, while BMP7 decreased. In the lungs, Id1 expression was correlated to BMP4 and BMPR2 and inversely correlated to gremlin-1 expression. Myocardial expressions of BMPR2, BMPR1A, BMP7 and SERCA-2A decreased, while gremlin-1 and noggin expressions increased on E17. On E21, myocardial expressions of Id1 and SERCA-2A decreased, while gremlin-1 expression increased. Moreover, BMPR2 and BMPR1A expressions were correlated to SERCA-2A expression and inversely correlated to pro-apoptotic Bax/Bcl2 ratio within the myocardium.

CONCLUSION

Downregulation of BMP signaling seems to contribute to pulmonary and myocardial anomalies observed in nitrofen-induced CDH.

Prolonged overcirculation-induced pulmonary arterial hypertension as a cause of right ventricular failure

AIMS

Three-month chronic systemic-to-pulmonary shunting in growing piglets has been reported as an early pulmonary arterial hypertension (PAH) model with preserved right ventricular (RV) function. We sought to determine whether prolonged shunting might be associated with more severe PAH and RV failure.

METHODS AND RESULTS

Fourteen growing piglets were randomized to a sham operation or the anastomosis of the left innominate artery to the pulmonary arterial trunk. Six months later, the shunt was closed and the animals underwent haemodynamic evaluation followed by tissue sampling for pathobiological assessment. Prolonged shunting had resulted in increased mean pulmonary artery pressure (22 ± 2 versus 17 ± 1 mmHg) and pulmonary arteriolar medial thickness, while cardiac output was decreased. However, RV-arterial coupling was markedly deteriorated, with a ~50% decrease in the ratio of end-systolic to pulmonary arterial elastances (Ees/Ea). Lung tissue expressions of endothelin-1, angiopoietin-1, and bone morphogenetic protein receptor-2 were similarly altered compared with previously observed after 3-month shunting. At the RV tissue level, pro-apoptotic ratio of Bax-to-Bcl-2 expressions and caspase-3 activation were increased, along with an increase in cardiomyocyte size, while expressions in voltage-gated potassium channels (Kv1.5 and Kv2.1) and angiogenic factors (angiopoietin-2 and vascular endothelial growth factor) were decreased. Right ventricular expressions of pro-inflammatory cytokines [interleukin (IL)-1α, IL-1β, tumour necrosis factor-α (TNF-α)] and natriuretic peptide precursors (NPPA and NPPB) were increased. There was an inverse correlation between RV Ees/Ea and pro-apoptotic Bax/Bcl-2 ratios.

CONCLUSIONS

Prolonged left-to-right shunting in piglets does not further aggravate pulmonary vasculopathy, but is a cause of RV failure, which appears related to an activation of apoptosis and inflammation.

[Pulmonary granulomatous necrotizing vasculitis: an extra-intestinal manifestation of ulcerative colitis or Wegener's granulomatosis?]

Respiratory symptoms are rare manifestations of ulcerative colitis as well as intestinal manifestations in Wegener granulomatosis. We report the case of a 17-year old man previously diagnosed as having ulcerative colitis who presented with diffuse thoracic pain. Hypermetabolic pulmonary nodules were discovered at the positron emission tomographic scan. Necrotizing granulomatous vasculitis was demonstrated at lung biopsy. In this paper, we describe the association between pulmonary nodules and ulcerative colitis and we discuss the possibility of an overlap syndrome between ulcerative colitis and Wegener granulomatosis.

Sildenafil added to sitaxsentan in overcirculation-induced pulmonary arterial hypertension

Experimental left-to-right shunt-induced pulmonary arterial hypertension (PAH) can be partially prevented by the endothelin-A receptor blocker sitaxsentan or by the phosphodiesterase-5 inhibitor sildenafil. We hypothesized that the combined administration of these drugs would completely prevent shunt-induced PAH, arguing in favor of a major role of endothelial dysfunction in the initiation of the disease. Twenty-four 3-wk-old piglets were randomized to a sham operation or to placebo, sitaxsentan therapy, or sitaxsentan combined with sildenafil after the anastomosis of the left subclavian artery to the pulmonary arterial trunk. Three months later, the animals underwent a hemodynamic evaluation, followed by pulmonary tissue sampling for morphometry and quantitative real-time PCR for endothelin-1, angiopoietin-1, and bone morphogenetic protein receptor (BMPR) signaling molecules. Three months of left-to-right shunting induced an increase in pulmonary vascular resistance (PVR) and medial thickness, an overexpression of endothelin-1, and angiopoietin-1 and decreased expressions of BMPR-2 and BMPR-1A. Sitaxsentan partially prevented a shunt-induced increase in PVR, medial thickness, and associated biological disturbances. Sildenafil combined with sitaxsentan normalized PVR, medial thickness, and the expression of endothelin-1. However, the expression of angiopoietin-1 remained increased, and the expressions of BMPR-1A and BMPR-2 were incompletely returned to normal. The coupling of right ventricular end-systolic to arterial elastances was maintained in all circumstances. Sitaxsentan combined with sildenafil prevents shunt-induced PAH more effectively than sitaxsentan alone, suggesting a major role for the targeted signaling pathways in the initiation of the disease. Sitaxsentan alone or combined with sildenafil did not affect right ventricular function.

[Medical complications of lung transplantation]

In 2010, lung transplantation is a valuable therapeutic option for a number of patients suffering from of end-stage non-neoplastic pulmonary diseases. The patients frequently regain a very good quality of life, however, long-term survival is often hampered by the development of complications such as the bronchiolitis obliterans syndrome, metabolic and infectious complications. As the bronchiolitis obliterans syndrome is the first cause of death in the medium and long term, an intense immunosuppressive treatment is maintained for life in order to prevent or stabilize this complication. The immunosuppression on the other hand induces a number of potentially severe complications including metabolic complications, infections and malignancies. The most frequent metabolic complications are arterial hypertension, chronic renal insufficiency, diabetes, hyperlipidemia and osteoporosis. Bacterial, viral and fungal infections are the second cause of mortality. They are to be considered as medical emergencies and require urgent assessment and targeted therapy after microbiologic specimens have been obtained. They should not, under any circumstances, be treated empirically and it has also to be kept in mind that the lung transplant recipient may present several concomitant infections. The most frequent malignancies are skin cancers, the post-transplant lymphoproliferative disorders, Kaposi's sarcoma and some types of bronchogenic carcinomas, head/neck and digestive cancers. Lung transplantation is no longer an exceptional procedure; thus, the pulmonologist will be confronted with such patients and should be able to recognize the symptoms and signs of the principal non-surgical complications. The goal of this review is to give a general overview of the most frequently encountered complications. Their assessment and treatment, though, will most often require the input of other specialists and a multidisciplinary and transversal approach.

[Tako-Tsubo syndrome after anaphylaxis caused by succinylcholine during general anaesthesia]

The Tako-Tsubo syndrome (or transient left ventricular apical balloning) is a new clinical entity, very similar to acute myocardial infarction, but different by its excellent short-term prognosis. It has been reported after a physical or an emotional stress, and it is diagnosed by a coronary angiogram and a left ventriculography. We report here a case of Tako-Tsubo syndrome related to an anaphylactic shock caused by succinylcholine during general anaesthesia of a female patient, wearing an unadjustable gastric band.

Sitaxsentan for the prevention of experimental shunt-induced pulmonary hypertension

We previously reported on the partial prevention of experimental shunt-induced pulmonary arterial hypertension (PAH) by the nonselective endothelin (ET) ET-A/ET-B receptor antagonist bosentan. As the respective roles of the ET-A and ET-B receptor signaling in the pathobiology of the disease remain undefined, we investigated the effects of selective ET-A receptor blockade by sitaxsentan in the same early stage PAH model. Twenty-one 3-wk-old piglets were randomized to placebo or sitaxsentan therapy (1.5 mg/kg/d), after anastomosis of the left subclavian artery to the pulmonary arterial trunk or after a sham operation. Three months later, the animals underwent a hemodynamic evaluation, followed by pulmonary tissue sampling for morphometry and real-time-quantitative-PCR for ET-1, angiopoietin-1, and bone morphogenetic receptor (BMPR) signaling molecules. Three months of left to right shunting induced an increase in pulmonary vascular resistance (PVR) and medial thickness, an overexpression of ET-1, ET-B receptor, and angiopoietin-1, and a decreased expression of BMPR-2 and BMPR-1A. Pretreatment with sitaxsentan prevented shunt-induced increase in PVR and decreased medial thickness by 64%. Sitaxsentan therapy completely prevented the decreased expression of BMPR-2 and limited the overexpression of ET-1, ET-B and angiopoietin-1, and the decreased expression of BMPR-1A. In conclusion, selective ET-A receptor blockade partially prevents shunt-induced PAH.

Effects of sildenafil on hypoxic pulmonary vascular function in dogs

Sildenafil has been shown to be an effective treatment of pulmonary arterial hypertension and is believed to present with pulmonary selectivity. This study was designed to determine the site of action of sildenafil compared with inhaled nitric oxide (NO) and intravenous sodium nitroprusside (SNP), known as selective and nonselective pulmonary vasodilators, respectively. Inhaled NO (40 ppm), and maximum tolerated doses of intravenous SNP and sildenafil, (5 microg x kg(-1) x min(-1) and 0.1 mg x kg(-1) x h(-1)), respectively, were administered to eight dogs ventilated in hypoxia. Pulmonary vascular resistance (PVR) was evaluated by pulmonary arterial pressure (Ppa) minus left atrial pressure (Pla) vs. flow curves, and partitioned into arterial and venous segments by the occlusion method. Right ventricular hydraulic load was defined by pulmonary arterial characteristic impedance (Zc) and elastance (Ea) calculations. Right ventricular arterial coupling was estimated by the ratio of end-systolic elastance (Ees) to Ea. Decreasing the inspired oxygen fraction from 0.4 to 0.1 increased Ppa - Pla at a standardized flow of 3 l x min(-1) x m(-2) from 6 +/- 1 to 18 +/- 1 mmHg (mean +/- SE). Ppa - Pla was decreased to 9 +/- 1 by inhaled NO, 14 +/- 1 by SNP, and 14 +/- 1 mmHg by sildenafil. The partition of PVR, Zc, Ea, and Ees/Ea was not affected by the three interventions. Inhaled NO did not affect systemic arterial pressure, which was similarly decreased by sildenafil and SNP, from 115 +/- 4 to 101 +/- 4 and 98 +/- 5 mmHg, respectively. We conclude that inhaled NO inhibits hypoxic pulmonary vasoconstriction more effectively than sildenafil or SNP, and sildenafil shows no more selectivity for the pulmonary circulation than SNP.

Hypertension artérielle pulmonaire en anesthésie–réanimation

OBJECTIVE

To review the perioperative anaesthetic management of pulmonary arterial hypertension.

DATA SOURCES

Extraction from Pubmed database of French and English articles on the perioperative anaesthetic management of pulmonary hypertension for 9 years.

DATA SELECTION

The collected articles were reviewed and selected according their quality and originality. The more recent data were selected.

DATA SYNTHESIS

Pulmonary arterial hypertension is classically divided in primary and secondary. Primary pulmonary hypertension (familial and sporadic) is relatively severe and rare. Muscularization of the terminal portion of the pulmonary vascular arterial tree, caused by smooth muscle cell hyperplasia is the first change. Pulmonary arterial hypertension linked with disorders of the respiratory system and hypoxemia or pulmonary venous hypertension including mitral valve disease and chronic left ventricular dysfunction are often associated with high morbidity and mortality. The main consequence of pulmonary hypertension development is the occurrence of right-sided circulatory failure. A better understanding of disease pathophysiology will contribute to the development of new therapies increasing then the prognosis of these patients. The management of primary pulmonary hypertension or secondary pulmonary arterial hypertension is a challenge for the anaesthesiologist because the risk of right ventricular failure is markedly increased.

Signaling Molecules in Overcirculation-Induced Pulmonary Hypertension in Piglets

Background— The phosphodiesterase type-5 (PDE-5) inhibitor sildenafil has been reported to improve pulmonary arterial hypertension (PAH), but the mechanisms that account for this effect are incompletely understood. Severe pulmonary hypertension has been characterized by defects in a signaling pathway involving angiopoietin-1 and the bone morphogenetic receptor-2 (BMPR-2). We investigated the effects of sildenafil on hemodynamics and signaling molecules in a piglet overcirculation-induced model of early PAH.

Methods and Results— Thirty 3-week-old piglets were randomized to placebo or sildenafil therapy 0.75 mg/kg TID after anastomosis of the left subclavian artery to the pulmonary arterial trunk or after a sham operation. Three months later, the animals underwent a hemodynamic evaluation followed by pulmonary tissue sampling for morphometry, immunohistochemistry or radioimmunoassay, and real-time quantitative-polymerase chain reaction. Chronic systemic-to-pulmonary shunting increased pulmonary mRNA for angiopoietin-1, endothelin-1 (ET-1), angiotensin II, inducible nitric oxide synthase, vascular endothelial growth factor, and PDE-5. Pulmonary messenger RNA for BMPR-1A and BMPR-2 decreased. Pulmonary angiotensin II, ET-1, and vascular endothelial growth factor proteins increased. Pulmonary artery pressure increased from 20±2 to 33±1 mm Hg, and arteriolar medial thickness increased by 91%. The expressions of angiopoietin-1, ET-1, and angiotensin II were tightly correlated to pulmonary hypertension. Sildenafil prevented the increase in pulmonary artery pressure, limited the increase in medial thickness to 41%, and corrected associated biological perturbations except for the angiopoietin-1/BMPR-2 pathway, PDE-5, and angiotensin II.

Conclusions— Sildenafil partially prevents overcirculation-induced PAH and associated changes in signaling molecules. Angiotensin II, PDE-5, and angiopoietin-1/BMPR-2 signaling may play a dominant role in the early stages of the disease.

Expression of the serotonin 1b receptor in experimental pulmonary hypertension

The pathogenesis of pulmonary arterial hypertension (PAH) remains uncertain. Both the serotonin and endothelin (ET) systems are believed to be involved. Recent studies pointed to the importance of the serotonin 2B receptor as a limiting step. The current authors investigated the lung tissue expression of serotonin receptors and of the serotonin transporter (5-HTT) by real-time-quantitative polymerase chain reaction in chronic overcirculation-induced PAH in growing piglets, with and without treatment with the dual ET receptor blocker bosentan. Pulmonary haemodynamic changes were described by pulmonary arterial impedance spectra. Three months after the surgical anastomosis of the left subclavian artery to the pulmonary arterial trunk, there was a shift of the impedance spectra to higher ratios of pressure and flow moduli, with increases in both 0 Hz impedance and characteristic impedance, and these changes were completely prevented by bosentan therapy. There was an increase in the expression of the serotonin 1B receptor. There was no change in the expression of the 5-HTT, and of the serotonin 2B, 1D, and 4 receptors. The overexpression of the serotonin 1B receptor was partially prevented by bosentan therapy. The present authors conclude that this early pulmonary arterial hypertension model is characterised by an endothelin receptor-dependent increased expression of the serotonin 1B receptor.

Early activation of cardiac and renal endothelin systems in experimental heart failure

We investigated the time course of the expression of cardiac and renal endothelin systems in tachycardia-induced heart failure in dogs. Eleven beagles underwent rapid pacing at a progressively increased rate over a period of 5 wk, with a weekly clinical examination, echocardiography, measurement of circulating and urinary endothelin-1 (ET-1), and myocardial and renal tissue biopsies. Real-time quantitative PCR was used for determinations of tissue prepro-ET-1 (ppET-1), ET-1-converting enzyme (ECE-1), and ETA and ETB receptor mRNA. Cardiac and renal tissue ET-1 contents were evaluated by immunostaining and measured by radioimmunoassay at autopsy. Rapid pacing caused a progressive increase in end-systolic and end-diastolic ventricular volumes (P < 0.05) from week 2 together with a decrease in ejection fraction and in mean velocity of circumferential shortening (P < 0.05) from week 1. These changes were tightly correlated to myocardial ppET-1 and renal ETA receptor mRNA and less so to myocardial ECE-1 mRNA, and they occurred before any increase in plasma and urinary ET-1 (P < 0.05 from week 4) and clinical signs of heart failure. Renal ppET-1 did not change. Both cardiac and renal ET-1 peptide contents were increased at autopsy. We conclude that tachycardia-induced heart failure in dogs is characterized by an early activation of the cardiac and renal tissue endothelin systems, which occurs before any changes in circulating and urinary ET-1 and is closely related to altered ventricular function.

Conversion from ministernotomy to full sternotomy in aortic valve replacement

Conversion (C) from ministernotomy (M.S.) to full sternotomy was necessary in 5% of the cases in a series of 100 patients consecutively operated for Aortic Valve Replacement (A.V.R.) Analysis of the demographics and surgical techniques indicate older age, aortic fragility, diffuse coronary disease, chronic renal failure and left vent insertion as contributing factors. Despite increased operative blood losses, extra-corporeal circulation (E.C.C.) times, intensive care unit (I.C.U.) stay and hospital stay, no mortality was observed in the conversion group, as compared to 4.2% mortality in the total ministernotomy (MS) population. Preoperative patients selection, avoidance of technical pitfalls, and knowledge of alternative surgical measures are suggested to further decrease the incidence of conversions.

The use of disharmonic motion curves in problems of the cervical spine

Cervical spine motion was investigated by three-dimensional electrogoniometry in 257 asymptomatic volunteers and in 32 patients with cervical disc hernia or whiplash syndrome. Maximal ranges of main and coupled motions were considered. Motion curves were analysed qualitatively and using fitting of sixth degree polynomials. Motion ranges obtained were in agreement with previous observations. Significant differences between patients and volunteers concerned several primary and coupled components but not all. Qualitatively, patients displayed less harmonic curves, with irregularities and plateau-like appearances. Root mean square differences between data and fit were significantly modified in patients. Although cervical spine motion ranges may remain within normal limits in patients, motion patterns were altered qualitatively and quantitatively. Motion pattern analysis might prove a useful discrimination parameter in patients in whom anatomical lesions are not clearly identifiable.

Normal global motion of the cervical spine: an electrogoniometric study

OBJECTIVE

Establishment of a normal database and clinical reference of active global cervical spine motion ranges and patterns using a commercial electrogoniometer.

DESIGN

Three-dimensional cervical motion ranges and patterns were analyzed in 250 asymptomatic volunteers.

BACKGROUND

In vivo out-of-plane motion patterns of the cervical spine have not yet been reported in large populations, but could be of clinical interest.

METHODS

In 250 subjects (aged 14-70 yr), motion range and patterns between the first thoracic vertebra and the head were analyzed for flexion-extension, lateral bending, rotation in neutral sagittal plane position and in full flexion using the CA 6000 Spine Motion Analyzer.

RESULTS AND CONCLUSIONS

Average motion range in the sagittal plane was 122 degrees (SD: 18 degrees ). Flexion was slightly more important than extension. Out-of-plane components were negligible. Global bending range averaged 88 degrees (SD: 16 degrees ), left and right bending being comparable. Homolateral rotation was associated to lateral bending. Its extent was approximately 40% of the bending range. Global rotation range in neutral sagittal plane position was 144 degrees (SD: 20 degrees ), without significant difference between right and left rotations. Associated motion components were small. During rotation in flexed head position, global range (134 degrees, SD: 24 degrees ) was comparable to the one in neutral flexion. But heterolateral bending, averaging 60% of the primary motion, was associated to flexed rotation. Significant reduction of all primary (but not conjunct) motions with age were obtained. Sex had no influence on cervical motion range.

RELEVANCE

Our results agreed with previous observations, validating the methodology used. They thus constitute reference data of cervical out-of-plane motion for clinical applications.