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P Lacombe

Publications and source records attributed to P Lacombe.

At least 55 records · Page 3Linked to original sources
PubMed1999

[Preoperative angiographic landmarks of the gluteal muscle regions using Patent Blue V].

Use of a gluteus musculocutaneous flap is the most reliable technique for surgical repair of sacral ulcers. Surgery could be ideally performed when the flap is designed using only the upper or the lower half of the glutens maximus muscle depending on the superior gluteal artery or the inferior gluteal artery, respectively. The authors have developed a technique for preoperative demonstration of the vascular supply to both muscle and overlying skin from a single gluteal artery using superselective catheterization and arterial administration of a dye (Patent Blue V). This technique facilitates the surgical procedure but assessment of its usefulness will require further evaluation.

Angiography↗
PubMed1999

[Post-traumatic aneurysmal dissection of the extracranial internal carotid artery; helical computed tomographic and angiographic aspects: a case].

A 20-year-old man presented with mild intracranial bleeding, a Horner's syndrome, and left neck swelling following head injury. Following noncontrast CT of the brain, a contrast-enhanced helical CT was performed through the neck that showed a hematoma in the poststyloid space (carotid sheath) with irregular diameter of the ICA. Selective digital subtraction angiography confirmed the presence of left cervical ICA dissection with pseudoaneurysm formation. The aneurysm was resected and an end-to-end anastomosis was done using an inverted saphenous graft. Histology confirmed a diagnosis of traumatic ICA dissection with pseudoaneurysm formation and there was no evidence of pre-existing pathology. Helical CT is a simple, widely available, and relatively non-invasive imaging technique that correlates well with angiography. It should be considered in the evaluation of patients with suspected cervical ICA dissection.

Accidents, Traffic↗
PubMed1999

Percutaneous gastrostomy for enteral nutrition: long-term follow-up of 176 procedures.

OBJECTIVE: To evaluate the efficacy and safety of percutaneous gastrostomy (PG), using small catheters without gastropexy, to deliver enteral nutrition. METHODS: We reviewed the records of 176 consecutive patients in whom PG was attempted for enteral nutrition. Of these cases, 172 catheters were inserted by the Seldinger technique under fluoroscopic guidance alone, 2 were inserted under computed tomographic guidance, and 2 procedures failed. In primary procedures, 8.5- or 10.2-French catheters were used. RESULTS: The technical success rate was 98.9%. Of the 176 procedures, 2 failed because of the high position of the stomach. Seven-day follow-up was obtained in all patients; 30-day follow-up in 145 patients (83%), and long-term follow-up (30 to 1512 days) in 123 patients (70%). The 30-day mortality rate was 13.2%. One death (0.5%) was directly related to the procedure. Major complications occurred in 4 patients (2.2%), and minor complications in 12 patients (6.9%). No patient required surgery for complications attributable to the gastrostomy procedure. CONCLUSION: PG without gastropexy using small catheters is a simple, safe and effective technique for delivering enteral nutrition.

Adult↗
PubMed1999

[Arterial lipiodol chemoembolization of a left liver metastasis through the right internal thoracic artery].

The purpose of this article is to illustrate the efficacy of the chemoembolization in patients with hypervascular metastases and to describe the post-embolization change in vascularization pattern. Unusual collaterals may develop following embolization. A 59-year-old woman, followed for unresectable small bowel carcinoid tumor since 1991, underwent successful chemoembolization of several liver metastases. Only one liver lesion, located in segment IV, showed interval increase in size. This lesion was supplied by the right internal mammary artery. A branch of the right internal mammary artery was catheterized using a microcatheter and embolization was performed using doxorubicine-Lipiodol (Adriblastine, Lipiodol) and gelfoam (Spongel). No complications occurred after the procedure. The right internal mammary artery should be considered as a possible source of collateral arterial supply to the liver and should be evaluated in patients with local progression of disease.

Antibiotics, Antineoplastic↗
PubMed1999

[Helical computed tomography of the aorta and its branches].

Imaging of the aorta has greatly benefited from the recent development of helical computed tomography. This noninvasive and widespread imaging technique could be considered as a viable alternative to invasive modalities in aortic disease assessment, especially in the acute onset. Radiologists should be familiar with the principles of this technique and its clinical applications. This report develops technical aspects, typical and atypical features of a variety of noncongenital aortic diseases including dissections, aortic trauma, aneurysms, nonaneurysmal atherosclerotic diseases and arteritis. The role of helical CT as noninvasive tool for imaging the aorta and its branches is compared to the other imaging methods.

Acute Disease↗
PubMed1999

[Bronchial and pulmonary vaso-occlusions].

The technique of vaso-occlusion (or embolisation) consists in occluding one or several vessels which are causing haemoptysis. Either of the pulmonary circulations (systemic bronchial or pulmonary) may be the cause and sometimes both are. In systemic pulmonary hypervascularization the pathological issues are affected by high pressure vascularisation at the expense of functional vascularisation and are the source of frequent episodes of bleeding. Bronchial and systemic vaso-occlusion has proven efficacy and safety on condition that strict rules are respected to avoid complications; the detection of potentially dangerous arteries (spinal, coronary and visceral) and a choice of material for embolisation which is adapted to the therapeutic strategy and the clinical and angiographic presentation. The indications for the procedure are dictated by severe or recurrent haemoptysis. Vaso-occlusion of pulmonary arteries which is a rarer indication dominated by conditions such as arteriovenous malformation (MAVP). The technique is adapted to the number, to the size and to the diffusion of MAVP which is characterised precisely by computed tomography. Vaso-occlusion is the treatment of first choice for MAVP only leaving failures of vaso-occlusion to surgery and certain pedicular forms have a very short afferent of large calibre.

Arteriovenous Malformations↗
PubMed1999

[Late solitary metastasis of a renal cancer to the contralateral adrenal gland].

We report a case of metachronous metastasis from renal cell carcinoma to the contralateral adrenal gland detected one year after radical nephrectomy. The initial tumor was incidentally discovered in the setting of acute aortic dissection. A large left adrenal tumor was detected on CT follow-up at two years. Retrospectively, a hypervascular lesion was present on the first yearly CT examination. Adrenalectomy was performed. There is no evidence of recurrent disease at 12 months. The patient was also treated with oral steroids. Because of their location and of the particularities of available therapeutic options, and because these metastases can occur late, long-term sonographic and CT follow-up should be performed. The clinical, imaging, therapeutic and prognostic aspects of these lesions will be discussed.

Adrenal Gland Neoplasms↗
PubMed1998

Structural organization of the perivascular astrocyte endfeet and their relationship with the endothelial glucose transporter: a confocal microscopy study.

Despite the increasing evidence for a prominent role played by the perivascular endfeet of astrocytes in the functional metabolic coupling between astrocytes and neurons, a clear picture of their spatial organization is still lacking. To examine the three-dimensional structure of the astrocyte endfeet and their relationships with the endothelial cells, coronal rat brain sections immunolabeled for the two astroglial markers [glial fibrillary acidic protein (GFAP)/S-100beta] and the endothelial glucose transporter (GLUT1) were analyzed under the confocal microscope. Double immunolabeling of GFAP and S-100beta showed numerous well-defined astrocytes sending one or more endfeet to the vasculature. Examination of GFAP immunolabeling at higher magnification showed that these endfeet consist of well-defined rosette-like structures lying on the vessel wall. Double immunostaining of GFAP and GLUT1 showed that the endothelial cells were the main targets of these repeated geometrical units formed by the astrocyte endfeet. When three-dimensional images were reconstructed, obvious privileged anatomical relationships were observed between endfeet and individual endothelial cells. These anatomical data provide strong support for the involvement of astrocytes in cerebral metabolic coupling. The finger-like appearance of astrocyte endfeet could allow direct metabolic exchanges between intracerebral vessels and non-glial elements such as nerve terminals.

Animals↗
PubMed1998

[The value of transesophageal echocardiography for the diagnosis of pulmonary embolism with acute pulmonary heart disease].

Transoesophageal echocardiography is a method of visualising intracardiac thrombi and could therefore be useful for the diagnosis of pulmonary embolism, but its diagnostic value is unknown. The authors carried out a prospective study with this diagnostic tool in massive pulmonary embolism. The study protocol was to perform transthoracic echocardiography in patients with suspected acute pulmonary embolism and then to perform transoesophageal echocardiography when there were signs of acute cor pulmonale. The results of both echocardiographic investigations were compared with two reference radiological techniques: the spiral CT scan and/or pulmonary angiography. Fifty-six patients underwent transthoracic echocardiography. In the 34 patients with transthoracic echocardiographic signs of acute cor pulmonale, the positive predictive value of the investigation for pulmonary embolism was 91% and the negative predictive value was 54%. Twenty of these 34 patients underwent transoesophageal echocardiography. The sensitivity and specificity for the diagnosis of proximal embolism were 85% and 86% respectively. The limitations of the method were poor visualisation of the left pulmonary artery in which only one thrombus was detected, compared with 6 by spiral CT scan, and the absence of visualisation of lobar arteries. Consequently, the real sensitivity of transoesophageal echocardiography for visualisation of all thrombi in the pulmonary arteries in acute cor pulmonale was only 55%. In acute cor pulmonale, the diagnostic value of transoesophageal echocardiography is poor because the sensitivity for visualisation of intra-pulmonary arterial thrombi is low compared with other radiological techniques. However, in patients with proximal emboli in the right or main pulmonary artery, the diagnosis may be established in a few minutes without the need of other more invasive techniques. Nevertheless, normal transoesophageal echocardiography does not rule out the presence of proximal in the left pulmonary artery or distal emboli in the lobar arteries.

Acute Disease↗
PubMed1997

Reduced cortical vasodilatory response to stimulation of the nucleus basalis of Meynert in the aged rat and evidence for a control of the cerebral circulation.

In earlier studies we showed that electrical stimulation of the rat nucleus basalis of Meynert (NBM) induces large increases in cerebral blood flow, mainly through cholinergic mechanisms. We then investigated the effect of aging on this influence by measuring cortical blood flow (CoBF) and tissue gas partial pressures (PtO2, PtCO2) in the conscious young adult and aged rat. NBM stimulation increased frontal (+101%) and parietal (+29%) CoBF in young rats. The effects were halved in aged rats. Moreover, PtO2 was significantly increased in young but not in aged rats. By contrast, the corticovascular reactivity to hypercapnia did not differ between young and aged rats, nor did the potentiating vasodilator effect of physostigmine. In combined autoradiographic measurements of cerebral blood flow and cerebral glucose utilization, we recently found that the cortical circulatory response to NBM stimulation was not accompanied by significant metabolic change. Thus, the blood flow changes observed in the cortex cannot be ascribed to increased metabolic activity. The distribution of this uncoupling coincides with that of cholinergic NBM projections directly impinging on cortical microvessels. These data support the cortical microcirculation and suggest the possible involvement of NBM dysfunction in the pathology of cortical microcirculation.

Aging↗
PubMed1997

Cerebrovascular consequences of altering serotonergic transmission in conscious rat.

Many therapeutic strategies aim at altering serotonin brain levels. However, serotonin (5-HT) is known to influence the cerebral circulation. The purpose of this study was to determine the effects of acutely decreasing intracerebral serotonin release upon cerebral blood flow and cerebrovascular reactivity to hypercapnia in conscious rats. To this end, (1) we analyzed the time-course of cortical blood flow changes measured with laser-Doppler flowmetry following injection of 0.1 mg kg(-1) 8-OHDPAT (5-HT1A agonist), and (2) we evaluated the cerebrovascular reactivity to hypercapnia using a quantitative multiregional diffusible tracer technique 5 and 60 min following 8-OHDPAT administration. 8-OHDPAT induced a rapid and transient increase in cortical blood flow (+34%) that was prevented totally by WAY100135 (5-HT1A antagonist) pre-treatment. Five min following 8-OHDPAT administration, the cerebrovascular responsiveness to hypercapnia was increased significantly in striatum (+27%) and fronto-parietal cortex (+61%). This result is consistent with a vasoconstrictor role of the serotonergic system that becomes manifest during hyperemic conditions.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1997

Epidural analgesia and intravenous patient-controlled analgesia result in similar rates of postoperative myocardial ischemia after aortic surgery.

UNLABELLED: To assess the role of postoperative analgesia on myocardial ischemia after aortic surgery, we compared intravenous patient-controlled analgesia (PCA) with thoracic epidural analgesia (TEA). One hundred twenty-four patients were prospectively randomized to the PCA or TEA group. In the TEA group, a T6-7 or T7-8 epidural catheter was inserted before the induction of general anesthesia. Within 1 h of the end of surgery, analgesia and 24-h two-channel Holter monitoring were begun. Myocardial ischemia was defined as ST segment depression > or = 1 mm, 0.06 s after the J point, and lasting for more than 1 min. In the PCA group, a bolus of morphine, 0.05 mg/kg, was given, followed by 0.02 mg/kg of morphine on demand every 10 min. Bupivacaine 0.125% and fentanyl 10 microg/mL was used in the TEA group. Analgesics were titrated to maintain a visual analog scale score < or = 3. The overall incidence of myocardial ischemia was 18.4%-18.2% for TEA and 18.6% for PCA (P = not significant). There were no differences between the groups in the total duration of ischemia per patient (22.2 +/- 119.8 min for TEA and 20.5 +/- 99 min for PCA) and the number of episodes per patient (0.69 +/- 2.1 for TEA and 1.2 +/- 4.9 for PCA). Twenty-three patients had an adverse cardiac outcome, although there were no differences between the groups. The postoperative pain control was superior with TEA. In these patients undergoing elective aortic surgery, the use of postoperative TEA did not result in a lower incidence of early myocardial ischemia compared with intravenous PCA with morphine, despite better analgesia with TEA. IMPLICATIONS: Postoperative myocardial ischemia is associated with adverse cardiac outcome. Using Holter monitoring after aortic surgery, this study shows that the use of thoracic epidural analgesia with bupivacaine and fentanyl did not result in a lower incidence of myocardial ischemia compared with intravenous patient-controlled analgesia with morphine.

Aged↗
PubMed1997

Autoradiographic evidence for flow-metabolism uncoupling during stimulation of the nucleus basalis of Meynert in the conscious rat.

We earlier reported that electrical stimulation of the rat nucleus basalis of Meynert (NBM) induces large cerebral blood flow increases, particularly in frontal cortical areas but also in some subcortical regions. The present study was designed to address the issue of blood flow control exerted by NBM projections. To this aim, we have determined whether these flow increases were associated with proportionate changes in metabolic activity as evaluated by cerebral glucose utilization (CGU) strictly under the same experimental conditions in the conscious rat. An electrode was chronically implanted in a reactive site of the NBM as determined by laser-Doppler flowmetry (LDF) of the cortical circulation. One to two weeks later, while the cortical blood flow was monitored by LDF, we measured CGU using the [14C]2-deoxyglucose autoradiographic technique during unilateral electrical stimulation of the NBM, and analyzed the local flow-metabolism relationship. The large increases in cortical blood flow induced by NBM stimulation, exceeding 300% in various frontal areas, were associated with at most 24% increases in CGU (as compared with the control group) in one frontal area. By contrast, strong increases in CGU exceeding 150% were observed in subcortical regions ipsilateral to the stimulation, especially in extrapyramidal structures, associated with proportionate CBF changes. Thus, none of the blood flow changes observed in the cortex can be ascribed to an increased metabolic activity, whereas CBF and CGU were coupled in many subcortical areas. This result indicates that different mechanisms, which do not necessarily involve any metabolic factor, contribute to the regulation of the cerebral circulation at the cortical and subcortical level. Because the distribution of the uncoupling is coincident with that of cholinergic NBM projections directly reaching cortical microvessels, these data strongly support the hypothesis that NBM neurons are capable of exerting a neurogenic control of the cortical microcirculation.

Animals↗
PubMed1997

Local uncoupling of the cerebrovascular and metabolic responses to somatosensory stimulation after neuronal nitric oxide synthase inhibition.

It has recently been shown, using either genetically engineered mutant mice (nitric oxide synthase [NOS] knockout) or specific pharmacological tools, that type I NOS (neuronal isoform of NOS, [nNOS]) participates in coupling cerebral blood flow to functional activation. However, it has not been clearly established whether the associated metabolic response was preserved under nNOS inhibition and whether this action was exerted homogeneously within the brain. To address these issues, we analyzed the combined circulatory and metabolic consequences of inhibiting the nNOS both at rest and during functional activation in the rat anesthetized with alpha-chloralose. Cerebral blood flow and cerebral glucose use (CGU) were measured autoradiographically using [14C]iodoantipyrine and [14C]2-deoxyglucose during trigeminal activation induced by unilateral whiskers stimulation in vehicle- and 7-nitroindazole-treated rats. Our data show that inhibition of nNOS globally decreased CBF without altering CGU, indicating that NO-releasing neurons play a significant role in maintaining a resting cerebrovascular tone in the whole brain. During whisker stimulation, nNOS inhibition totally abolished the cerebrovascular response only in the second order relay stations (thalamus and somatosensory cortex) of the trigeminal relay without altering the metabolic response. These findings provide evidence that the involvement of neurally-derived NO in coupling flow to somatosensory activation is region-dependent, and that under nNOS inhibition, CBF and CGU may vary independently during neuronal activation.

Animals↗