PubMed Health⌕ Search

Biomedical subjects

R Krivosic-Horber

Publications and source records attributed to R Krivosic-Horber.

At least 55 records · Page 3Linked to original sources
PubMed1996

In vitro human masseter muscle hypersensitivity: a possible explanation for increase in masseter tone.

To determine whether a difference in fiber-type caffeine and Ca2+ sensitivities exists between human masseter and vastus lateralis skeletal muscle, we compared the fiber-type caffeine sensitivities in chemically skinned muscle fibers from 13 masseter and 18 vastus lateralis muscles. Caffeine sensitivity was defined as the threshold concentration inducing > 10% of the maximal tension obtained after the fiber was loaded with a 1.6 x 10(-2) mM Ca2+ solution for 30 s. Significant difference in the mean caffeine sensitivity was found between type I masseter fibers [2.57 +/- 1.32 (SD) mM] vs. type I (6.02 +/- 1.74 mM) and type II vastus lateralis fibers (11.25 +/- 3.13 mM). Maximal Ca(2+)-activated force per cross-sectional area was significantly different between masseter and vastus lateralis fibers. However, the Ca2+ concentration corresponding to half-maximal tension (pCa50) was not significantly different between type I masseter (pCa50 5.9 +/- 0.02) and type I vastus lateralis muscle (pCa50 6.01 +/- 0.08). These results suggest that the increase in caffeine sensitivity of masseter muscle reflects the presence of a low reactivity threshold of the sarcoplasmic reticulum.

Caffeine↗
PubMed1996

[Gamstorp's disease and pregnancy. A case report].

Gamstorp's disease or hyperkaliemic periodic paralysis is a rare pathology leading to spells of generalized hypotonia due to hyperkaliema. It is hard to say how far pregnancy affects the course of the disease and what is the impact of the disease on pregnancy. We report a case of Gamstorp's disease during pregnancy and we insist on the fact that because it can be crippling during its acute phases, close surveillance is needed during pregnancy. Screening for malignant hyperthermia should be carried out. During labour, kaliemia level should be monitored repeatedly and the expulsion phase kept as short as possible if necessary by forceps delivery.

Adult↗
PubMed1995

Evaluation of the Augustine Guide for difficult tracheal intubation.

Successful tracheal intubation with Augustine Guide (Augustine Medical, Inc., Eden Prairie, MN) in patients with normal airways has recently been described. There are no studies describing Augustine Guide (AG) use in patients with difficult airways. Accordingly, we studied AG intubation in a population of patients with expected difficult airways due to cervical spine pathology, limited mouth opening, obesity, facial trauma or deformity due to previous operation or radiation and in patients with unexpectedly difficult airways. A total of 44 patients were studied. The AG was used as a primary intubating tool in patients with known difficult airways (n = 36) and as a secondary intubating tool in patients with unexpected inability to intubate using conventional direct laryngoscopy (n = 8). Airway difficulty was predicted by history and physical examination. Intubations were performed under general anaesthesia in 40 of the 44 patients studied. In four patients with predictably difficult airways, topical anaesthesia and sedation were used. Backup methods to achieve intubation were available. Thirty-two of the 36 with known or suspected difficult airways were classified as Mallampati Class III or IV. In the remaining eight patients the preoperative examination suggested an easy airway; however, after induction of general anaesthesia, their laryngeal inlet could not be seen using direct laryngoscopy. Using the AG, all were intubated successfully (36/44 at the first attempt, in 8/44 repositioning of the AG to allow successful laryngeal entry of the stylet was necessary). There were no failures or complications secondary to AG use. This study shows that the AG is a useful device for oral tracheal intubation in patients with known or unexpectedly difficult airways.

Adult↗
PubMed1995

[Mild hypothermia and cerebral protection].

To define the part played by mild-to-moderate hypothermia in neuroprotection, it is necessary to take into account the thermoregulatory responses that occur in the normal human as the change in central temperature exceeds 0.2 degrees C. The mechanisms induced by cold are cutaneous vasoconstriction and shivering. They must be suppressed before starting controlled hypothermia. In these conditions, controlled moderate hypothermia between 32 and 35 degrees C does not seem to have deleterious side-effects, especially on coagulation. Caution is needed with the analysis of the numerous papers reporting experiments concerning the effects of moderate hypothermia in animals with induced cerebral ischaemia because of significant differences in the study designs. These differences concern mainly the time of onset of hypothermia, viz before or after ischaemia, the fact that the ischaemia is either global or focal, that it is caused by vascular occlusion posttraumatic or initiated by hypo or hyperglycemia. Some differences are also existing in the criteria used to appreciate the neuronal damage, as well as in the level of temperature and the site where it is measured. The mechanism of neuroprotection from moderate hypothermia seems to be not only a decrease in cerebral metabolism, but also involves a specific action on some intra-cellular events such as the blocking of the release of glutamate and of lipid peroxydation in brain tissue. An indirect proof of the neuroprotective effect of moderate hypothermia is the increase in the neuronal damage induced by moderate hyperthermia. It is conceivable that moderate hypothermia could exert a better neuroprotective effect than the drugs having this reputation, such as barbiturates, isoflurane and propofol.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthetics↗
PubMed1995

[Cervicofacial cellulitis of dental origin and tracheal intubation].

OBJECTIVES: To evaluate the difficulty of intubation in relation with the localisation and spread of cervico-facial cellulitis of odontogenic origin and to recognize the optimal technique of intubation in such circumstances. STUDY DESIGN: Prospective clinical open study. PATIENTS: Hundred patients, including 16 children, undergoing surgical drainage of a cervico-facial cellulitis of odontogenic origin under general anesthesia were studied. METHODS: Difficulty of intubation was evaluated with the following four criteria: active mouth opening in the awake patient, Mallampati's classifying system, presence of trismus, clinical and radiological control of localisation and extension of the cellulitis (mandibular, maxillar or mouth floor). In case of a foreseen difficult intubation, a fibrescope was used in the awake patient. Otherwise the endotracheal tube was inserted after administration of propofol (3 mg.k-1) and alfentanil (10 to 20 micrograms.kg-1). A Cormack's grading was performed during intubation. RESULTS: Mouth opening depended on the localisation of the cellulitis. Trismus occurred more often with mandibular than maxillary localisations. Trismus and a Mallampati's class > 2 were associated with difficulty in intubation (Cormack's grade > 2), except in maxillary localisations. CONCLUSIONS: The localisation of cellulitis of odontogenic origin is responsible for the difficulty grade of intubation. Awake fibreoptic intubation should be systematically performed in patients with a floor of the mouth cellulitis to reduce the risk of rupture of the abscess by a laryngoscope blade. As trismus associated with mandibular localisations is not relieved by general anaesthesia, awake fibreoptic endotracheal intubation should be preferred.

Adolescent↗
PubMed1995

[Retrograde percutaneous catheterization of the internal jugular vein in head injured patients].

The monitoring of jugular venous oxygen saturation and lactate concentration in order to detect cerebral ischaemia or hyperaemia requires the insertion of a fibreoptic catheter into the upper bulb of the internal jugular vein. With dissection studies we have defined superficial anatomical landmarks which are constant and easily palpable, namely the mastoid process and the sternocleidomastoid muscle. This technique does not require a rotation of the head. The puncture site is located at the top of a triangular area between its sternal and clavicular insertions. At this site the jugular vein is rather superficial. This study reports our experience of the retrograde catheterisation of the jugular vein in twelve severely head injured patients.

Adult↗
PubMed1995

[Management of neurologic manifestations after obstetrical epidural anesthesia].

Epidural anaesthesia is commonly used in obstetrics (70% of all deliveries in the maternity units of Lille University Hospital). Four cases are reported: headache followed by diplopia and amaurosis, delayed lumbosacral paraesthesia, early paraesthesia of the left lower limb, severe cephalalgia. Etiological analysis allowed to find the causes of these disorders and to exclude any anaesthesia responsibility, moreover permitting adapted treatments. The medicolegal aspect must be emphasized and also the need of an extensive medical investigation to find out the aetiology and propose an appropriate management.

Adult↗
PubMed1994

Mutation screening of the RYR1 gene in malignant hyperthermia: detection of a novel Tyr to Ser mutation in a pedigree with associated central cores.

The ryanodine receptor gene (RYR1) has been shown to be mutated in a small number of malignant hyperthermia (MH) pedigrees. Missense mutations in this gene have also been identified in two families with central core disease (CCD), a rare myopathy closely associated with MH. In an effort to identify other RYR1 mutations responsible for MH and CCD, we used a SSCP approach to screen the RYR1 gene for mutations in a family exhibiting susceptibility to MH (MHS) where some of the MHS individuals display core regions in their muscle. Sequence analysis of a unique aberrant SSCP has allowed us to identify a point mutation cosegregating with MHS in the described family. The mutation changes a conserved tyrosine residue at position 522 to a serine residue. This mutation is positioned relatively close to five of the six MHS/CCD mutations known to date and provides further evidence that MHS/CCD mutations may cluster in the amino terminal region of the RYR1 protein.

Amino Acid Sequence↗
PubMed1994

[Lack of sensitivity to per-anesthetic malignant hyperthermia in 32 patients who developed neuroleptic malignant syndrome].

The aim of this study was to verify whether a relationship exists between neuroleptic malignant syndrome (NMS) and anaesthetic-induced malignant hyperthermia (MH) or not. The in vitro halothane-caffeine tests were performed on muscle tissue obtained from 32 patients with documented NMS episodes. The diagnosis of NMS relied on Levenson's criteria. The results, expressed in accordance with the criteria of the European MH Group, defined 29 subjects as MH non-susceptible. Three patients were classified as MH equivocal. These findings demonstrate the lack of any link between NMS and MH. Therefore, patients with a history of NMS are not likely to be at risk of developing MH and special measures against MH are not required for anaesthesia in these patients.

Adolescent↗
PubMed1994

Detection of a novel common mutation in the ryanodine receptor gene in malignant hyperthermia: implications for diagnosis and heterogeneity studies.

Malignant hyperthermia (MH) is a potentially fatal autosomal dominant disorder of skeletal muscle and is triggered in susceptible people by all commonly used inhalational anaesthetics. To date, the ryanodine receptor gene (RYR1) has been shown to be mutated in a small number of malignant hyperthermia susceptible (MHS) cases. To determine if a common RYR1 mutation exists that might account for a significant number of MHS cases, we have investigated the RYR1 gene in unrelated patients for the presence of new mutations by the single-stranded conformation polymorphism method and have identified a novel Gly341Arg mutation which accounts for approximately 10% of Caucasian MHS cases. The implications of this common mutation in MHS diagnosis and heterogeneity studies are discussed.

Base Sequence↗
PubMed1994

[Lumbar disk herniation with surgical option: general versus local anesthesia. Round table].

Lumbar disc hernia is a frequent pathology whose treatment remains essentially surgical. The type of anesthesia can be general anesthesia with intubation and controlled ventilation, both mandatory due to the position, peridural or spinal anesthesia. The usual position is knee-chest position which impairs circulation and ventilation if some precaution are not taken. Spinal anesthesia has been chosen in more than 40% of the patients by Lille CHU Team. This choice is justified by the important level of satisfaction of the patients and the absence of complications due to the anesthesia in a series of 1871 consecutive spinal anesthesia for lumbar disc surgery.

Adolescent↗
PubMed1994

[Hemodynamic effects of genu-pectoral position during the surgery of lumbar disk herniation: spinal anesthesia versus general anesthesia].

Spinal anesthesia (SA) for lumbar disk surgery in the genu-pectoral position (GP) has been proposed as an alternative to general anesthesia (GA). This study compares the haemodynamic effects of GP in two groups of patients undergoing either SA (n = 43) or GA (n = 40). Mean arterial pressure (MAP) and heart rate (HR) were recorded before and after GP. MAP and HR were significantly lower in the GA group after GP. We conclude that SA during GP for lumbar disk surgery is haemodynamically well tolerated.

Adult↗
PubMed1993

[Subarachnoid hematoma after spinal anesthesia and low molecular weight heparin].

A case is reported of spinal subarachnoid haematoma occurring after spinal anaesthesia. The patient was given prophylactic pre and postoperative low molecular weight heparin. On the second postoperative day, he complained of backache and got a partial cauda equina syndrome. Magnetic resonance imaging carried out on the 6th day confirmed the presence of a spinal haematoma, which was removed surgically. One year later, the bilateral motor palsy which had involved several roots, had completely regressed. It remained a severe sensory loss associated with a loss of sphincter control. This case highlights the role of predisposing factors and the importance of early diagnosis.

Anesthesia, Spinal↗