Biomedical subjects

Luc Nguyen

Publications and source records attributed to Luc Nguyen.

5 recordsLinked to original sources

PubMed2006

[Propofol to facilitate spinal anesthesia in the lateral position in patients with femoral neck fracture].

PURPOSE: The aim of this study was to assess the feasibility and efficacy of propofol before positioning elderly patients with a femoral neck fracture in the lateral decubitus position, to perform a spinal anesthetic. METHODS: In this prospective and descriptive study, 79 consecutive patients, > 75 yr old, with a femoral neck fracture were included. Propofol, 0.5 mg x kg(-1), was administered. If loss of consciousness was not obtained (Ramsay score < or = 3/6), then additional doses of 0.25 mg x kg(-1) were given until a Ramsay score of 4 or 5 was attained. Then, the patient was turned to the lateral decubitus position, the fractured side up. The efficacy of propofol was assessed by observing a grimace during positioning and asking the patients if they had recall of pain. Hemodynamic data and oxygen saturation were collected. RESULTS: Forty-three patients required a single injection, 34 required two injections and only two patients required three injections. No grimace and no recall of pain were recorded during the study. There was no desaturation (SpO(2) < 92 %), and hypotension, defined as a systolic blood pressure decrease > 30% from baseline, was observed. CONCLUSION: Propofol is a simple and efficacious means of providing comfort while positioning elderly patients with a femoral head fracture before performing spinal anesthesia.

Aged↗

PubMed2006

[Epidural hematoma after hemorrhagic shock in a parturient].

PURPOSE: Epidural hematoma is a rare but serious complication of epidural anesthesia. We report a case of epidural hematoma, occurring in an obstetric patient after the epidural catheter had been withdrawn accidentally after an episode of hemorrhagic shock leading to a hypocoagulable state. CLINICAL FEATURES: A patient had the epidural catheter inserted during labour when coagulation was normal. She had a postpartum hemorrhage with alteration of coagulation (platelets 16 x 10(-9) x L(-1), thrombin time: 85 sec. Vital signs returned to normal after a general anesthetic, transfusion of blood products, volume repletion and ligation of hypogastric arteries. It was then noticed that the epidural catheter had been withdrawn inadvertently while the patient was hypocoagulable. The patient then developed neurological signs consistent with spinal cord compression due to an epidural hematoma. A hematoma extending from T3 to L5 was diagnosed by magnetic resonance imaging. Because the cord had minimal compression, no specific action was undertaken, other than clinical and radiological follow-up. There were no long-term sequelae. CONCLUSION: In the presence of an epidural hematoma, surgery for emergency cord decompression is usually required. Another option that receives increasing attention is to monitor neurological function, but the indications for this expectant treatment are not well defined.

Adult↗

PubMed2006

Infraclavicular brachial plexus block versus humeral block in trauma patients: a comparison of patient comfort.

In this prospective randomized study, we compared humeral block (HB) and infraclavicular brachial plexus block (ICB) with pain caused by the block as a primary outcome, assuming that ICB would cause less pain than HB. Patients undergoing emergency upper limb surgery were included in this study and received either ICB (group I, n = 52 patients) or HB (group H, n = 52 patients). Patients were asked to quantify the severity of the pain during the procedure using a visual analog scale from 0 to 100 mm and to identify which of the 4 components of the procedure was most unpleasant (skin transfixion, needle redirection in search of the nerves, local anesthetic injections, or electrical stimulation). The block was assessed every 5 min for 30 min after completion of the block. Overall visual analog scale scores for the block were 35 +/- 27 mm in group H versus 19 +/- 18 mm in group I (P < 0.0011). Electrical stimulation was the most unpleasant part of the block (group H, 29 +/- 15 mm versus group I, 15 +/- 10 mm) (P < 0.019). Time to perform the block was significantly shorter in group I (ICB, 6 +/- 4 min versus HB, 10 +/- 4 min; P < 0.0001). The onset time was 13 +/- 7 min for ICB and 9 +/- 3 min for HB (P < 0.05). No serious complications were observed. In summary, ICB is less painful, compared with HB, with a similar success rate.

Adult↗

PubMed2006

Spinal anesthesia using single injection small-dose bupivacaine versus continuous catheter injection techniques for surgical repair of hip fracture in elderly patients.

Aging and disease may make elderly patients particularly susceptible to hypotension during spinal anesthesia. We compared the hemodynamic effect of continuous spinal anesthesia (CSA) and small dose single injection spinal anesthesia (SA) regarding the incidence of hypotension. Seventy-four patients aged >75 yr undergoing surgical repair of hip fracture were randomized into 2 groups of 37 patients each. Group CSA received a continuous spinal anesthetic with a titration of 2.5 mg boluses every 15 min of isobaric bupivacaine, while group SA received a single injection spinal anesthetic with 7.5 mg of isobaric bupivacaine. The overall variations in noninvasive automated arterial blood pressure were not statistically significantly different in the 2 groups at baseline and after CSA or SA (not significant). In the SA group, 68% of patients experienced at least one episode of hypotension (decrease in systolic arterial blood pressure greater than 20% of baseline value) versus 31% of patients in the CSA group (P = 0.005). In the SA group, 51% of patients experienced at least one episode of severe hypotension (decrease in systolic arterial blood pressure more than 30% of baseline value) versus 8% of patients in the CSA group (P < 0.0001). In the CSA group, 4.5 +/- 2 mg of ephedrine was injected versus 11 +/- 2 mg in the SA group (P = 0.005). In the CSA group, 5 mg (2.5-10) of anesthetic solution was required versus 7.5 mg in the SA group (P < 0.0001). We conclude that, in elderly patients undergoing hip fracture repair, CSA provides fewer episodes of hypotension and severe hypotension compared with a single intrathecal injection of 7.5 mg bupivacaine.

Aged↗

PubMed2003

Hemangiosarcomas, medulloblastomas, and other tumors in Ink4c/p53-null mice.

Ink4 proteins inhibit the enzymatic activities of cyclin D-dependent kinases, thereby governing transcriptional programs that depend on the activities of the retinoblastoma protein and other retinoblastoma family members (p107 and p130). Mice lacking Ink4c and p53 spontaneously develop a broad spectrum of neoplasms, usually presenting with multiple tumors of different histological types and dying of cancer by 6 months of age. Whereas thymic lymphomas or pituitary tumors predominate in mice lacking p53 or Ink4c, respectively, animals lacking both genes develop many vascular tumors and also present with medulloblastomas not observed in the parental strains. Unlike p53, loss of the Arf tumor suppressor did not contribute to the appearance of vascular or cerebellar tumors. Vascular tumors ranged in severity from angiomas to hemangiosarcomas, some of which could be transplanted into immunocompromised mice. Intriguingly, loss of Ink4c but maintenance of at least one Ink4d allele was required for formation of medulloblastomas in p53-null mice. In situ hybridization revealed that, in newborn mice, Ink4c is detected in the pia mater and in an adjacent layer of rapidly dividing cells within the cerebellar external granule layer (EGL), whereas Ink4d is primarily expressed in Purkinje neurons. Because the pia mater and Purkinje cells sandwich the cerebellar EGL from which medulloblastomas are presumed to arise, Ink4 proteins might function in a cell-autonomous manner in governing neuronal cell cycle exit as well as in a non-cell-autonomous manner in controlling the production of diffusible mitogens and chemokines that influence postnatal development of the cerebellar EGL.

Animals↗