Effects of Propofol on H-reflex in Humans

2001 ◽  
Vol 94 (1) ◽  
pp. 32-37 ◽  
Author(s):  
Thomas Kerz ◽  
Hans-Jürgen Hennes ◽  
Annaïk Fève ◽  
Philippe Decq ◽  
Paul Filipetti ◽  
...  

Background Depression of spinal cord motoneuron excitability has been proposed to contribute to surgical immobility. The H-reflex, which measures alpha-motoneuron excitability, is depressed by volatile anesthetics, whereas the action of propofol is unknown. The objective of this study was to determine the effects of propofol anesthesia on the H-reflex. Methods In 13 patients (group 1), H-reflex was measured before (T0), 3 min after (T1), and 10 min after (T2) a 2-mg/kg bolus dose of propofol, followed by an infusion of 10 mg x kg(-1) x h(-1). Ten patients (group 2) were studied when propofol was given via a programmable pump set to a propofol blood concentration of 6 microg/ml, and 10 patients (group 3) were studied with the pump set to 9 microg/ml. Latencies and amplitudes of H-reflexes (H0, H1, H2) and M-responses (M0, M1, M2) of the soleus muscle were recorded, and H/M ratios (H0/M0, H1/M1, H2/M2) were calculated. Results In group 1, H-reflex amplitudes and the H/M ratio were diminished after induction with propofol (H0 vs. H1, P = 0.033; H0/M0 vs. H1/M1, P = 0.042). After 10 min of propofol infusion, the H2/M2 ratio was still decreased versus H0/M0 (P = 0.031). In group 2, no difference was detected. In group 3, propofol depressed H-reflex amplitudes at T2 (H0 vs. H2, P < 0.01), and amplitudes were also lower at T2 than at T1 (H1 vs. H2, P < 0.01). In this group, the H/M ratio decreased from T0 to T2 (H0/M0 vs. H2/M2, P < 0.002). Conclusions During steady state conditions using propofol as the sole agent, a depression of the H-reflex is observed only at a high blood concentration of 9 microg/ml. The authors suggest that immobility during propofol anesthesia is not caused by a depression of spinal motoneuron circuit excitability.

2021 ◽  
pp. 197140092098356
Author(s):  
Marwan Alkrenawi ◽  
Michael Osherov ◽  
Azaria Simonovich ◽  
Jonathan Droujin ◽  
Ron Milo ◽  
...  

Background Cervical discopathy and demyelinating lesions often co-exist in patients with multiple sclerosis (MS). Our study examines the possible association between these two pathologies. Methods Medical records and cervical magnetic resonance imaging scans of MS patients with cervical discopathy who were seen at our MS clinic during 2018 were retrospectively reviewed. The severity of the disc disease was classified as grade I (no compression), grade II (compression of the dural sac) and grade III (cord compression). The spinal cord in each scan was divided into six segments corresponding to the intervertebral space of the spine (C1–C6). Each segment was defined as containing demyelinating lesion and disc pathology (group 1), demyelinating lesion without disc pathology (group 2), disc pathology without demyelinating lesion (group 3) and no demyelinating lesion or disc pathology (group 4). Fisher’s exact test was used to test the association between demyelinating lesions and disc pathology. Results Thirty-four MS patients with cervical discopathy were included in the study (26 females; average age 42.9 ± 13.7 years; average disease duration 8.4 ± 5.4 years). A total of 204 spinal cord segments were evaluated. Twenty-four segments were classified as group 1, 27 segments as group 2, 52 segments as group 3 and 101 segments as group 4. There was no association between demyelinating lesions and the grade of disc disease ( p = 0.1 for grade I, p = 0.3 for grade II and p = 1 for grade III disc disease). Conclusion Our study did not find any association between cervical disc disease and demyelinating spinal cord lesion.


2018 ◽  
Vol 21 (1) ◽  
pp. 4-10 ◽  
Author(s):  
Melissa M. Stamates ◽  
David M. Frim ◽  
Carina W. Yang ◽  
Gregory L. Katzman ◽  
Saad Ali

OBJECTIVETethered cord syndrome (TCS) is a neurosurgical disorder with varied clinical manifestations believed to result from vascular compromise due to stretch forces on the spinal cord. Conventional supine MRI findings may include a low-lying conus medullaris, thickened or fat-infiltrated filum terminale, or lipoma; however, imaging sensitivity and specificity for tethered cord can be low. The purpose of this study was to evaluate the utility of prone MRI in the diagnosis of tethered and retethered spinal cord.METHODSMedical records were reviewed in 41 patients who underwent surgical release of tethered cord and in whom preoperative prone MRI sequences were available. Patients were divided into Group 1 (new TCS diagnosis) and Group 2 (recurrent TCS after previous untethering). Absolute conus ventral motion and motion as a percentage of canal width between supine and prone positions was measured in these 2 groups via sagittal T2-weighted sequences; these groups were compared with 30 consecutive patients (Group 3) who were classified as the normal control group.RESULTSThe mean ventral motion was as follows: Group 1 (absolute: 0.5 ± 0.5 mm [range 0–2.4 mm]; canal percentage: 3.7% ± 3.9% [range 0%–16.3%]); Group 2 (absolute: 0.4 ± 0.7 mm [range 0–2.6 mm]; canal percentage: 2.2% ± 3.7% [range 0%–14.0%]); and Group 3 (absolute: 3.4 ± 1.3 mm [range 1.4–5.6 mm]; canal percentage: 22.0% ± 7.2% [range 10.5%–36.1%]). Whereas 38/41 surgically treated patients with TCS had diminished (< 10% canal width) ventral motion on preoperative MRI, 30/30 controls had > 10% canal width motion. Sensitivity and specificity were thereby calculated as 92.7% and 100%, respectively.CONCLUSIONSIn the present series, prone imaging is found to be a sensitive and specific tool, and the authors believe it may have a role as supportive evidence in the diagnosis of tethered and retethered spinal cord.


2021 ◽  
Vol 11 (3) ◽  
pp. 110-117
Author(s):  
O.S. Nekhlopochyn ◽  
V.V. Verbov ◽  
Ia.V. Tsymbaliuk ◽  
M.V. Vorodi ◽  
Ie.V. Cheshuk

Background. Neuropathic pain is one of the principal secondary complications of spinal cord injury. The biological role of neuropathic pain has not been established yet. This type of pain is formed directly in the area of the spinal cord injury; therefore, it can be assumed that its intensity may characterize both degenerative and reparative processes. The aim of this work is to assess the possible relationship between the intensity of neuropa­thic pain in patients with spinal cord injury at cervical subaxial spine and the dynamics of neurological disorder regression. Materials and methods. We have performed a retrospective analysis of patients referred to outpatient department of the Romodanov Neurosurgery Institute of National Academy of Medical Sciences of Ukraine in the period from 2010 to 2020 after a surgical treatment of subaxial cervical spine traumatic injury. The extent of neurolo­gical disorders and the intensity of neuropathic pain were assessed within 5–7 and 11–13 months after surgery. Results. All 102 patients selected for analysis were divided into three groups depen­ding on the intensity of the registered pain sensations: 1) absence of constant pain sensations — 19.6 % of subjects, 2) moderate pain — 56.9 %, 3) severe neuropathic pain — 23.5 %. In the first group, the regression of neurological disorders was 3.5 (95% confidence interval (CI) 2.15–6.15), in the second — 25.0 (95% CI 24.14–29.58), in the third — 13.0 (95% CI 10.87–16.55). The differences are statistically significant (χ2 = 60.4, df = 2, p < 0.0001). In patients with severe neurological disorders, the dynamics of recovery did not correlate with the pain intensity. With ASIA B, the dynamics of group 1 was 8.5 (95% CI 10.56–27.56), of group 2 — 15.0 (95% CI 13.41–18.41), of group 3 — 10.5 (95% CI 7.45–14.89). With ASIA C functional class, the difference is even more pronounced: in group 1, the median was 8.0 (95% CI 0.83–20.83), in group 2 — 32.0 (95% CI 25.41–36.86), in group 3 — 15.5 (95% CI 10.27–27.4). With ASIA D, a similar trend was observed. Conclusions. The worst regression of neurological disorders is observed in patients without clinically significant pain, the best results of neurological dysfunction recovery are found in patients with mode rate neuropathic pain.


2017 ◽  
Vol 20 (3) ◽  
pp. 289-297 ◽  
Author(s):  
Goichiro Tamura ◽  
Nobuhito Morota ◽  
Satoshi Ihara

OBJECTIVESacrococcygeal dimples in neonates and infants are of uncertain pathological import. Previously they were believed to be rarely associated with intraspinal anomalies. Recent studies using MRI, however, revealed that 6%–7% of pediatric cases of sacrococcygeal dimples were associated with anatomical tethered spinal cord (TSC). Because the prevalence of tethered cord syndrome is still unclear, there is no consensus among pediatric neurosurgeons on the management of children with sacrococcygeal dimples. The authors performed an analysis of MRI and urodynamic studies to validate their management strategy for pediatric cases of sacrococcygeal dimples.METHODSA total of 103 Japanese children (49 male and 54 female, median age 4 months, range 8 days–83 months) with sacrococcygeal dimples who were referred to the Division of Pediatric Neurosurgery between 2013 and 2015 were included in this study. The lumbosacral region of all the patients was investigated using MRI. Anatomical TSC was defined as a condition in which the caudal end of the conus medullaris is lower than the inferior border of the L2–3 intervertebral disc. Patients with minor spinal anomalies (e.g., anatomical TSC, filum lipoma, thickened filum, or filar cyst) underwent further urodynamic studies to ascertain the presence of neurogenic bladder (NGB). In this study, the presence of NGB without anatomical TSC but with other minor spinal anomalies was defined as “functional TSC.” The prevalence of anatomical and functional TSC was investigated. The association of the following cutaneous findings with spinal anomalies was also assessed: 1) depth of the dimple, 2) deviation of the gluteal fold, and 3) other skin abnormalities (e.g., discoloration, angioma, or abnormal hair).RESULTSThe children were classified into 4 groups: Group 1, patients with anatomical TSC; Group 2, patients with functional TSC; Group 3, patients without anatomical or functional TSC but with other minor spinal anomalies; and Group 4, patients with no spinal anomaly. There were 6 patients (5.8%) in Group 1, 8 patients (7.8%) in Group 2, 10 patients (9.7%) in Group 3, and 79 patients (76.7%) in Group 4. Twenty-four patients (23.3%; Groups 1, 2, and 3) showed MRI abnormalities, including filum lipoma (14 cases), filar cysts (5 cases), thickened filum (2 cases), and anatomical TSC without other spinal anomalies (3 cases). Untethering of the spinal cord was indicated for 14 patients (13.6%; Groups 1 and 2) with anatomical and functional TSCs. Preoperative NGB was found in 12 patients and improved postoperatively in 7 (58.3%). None of the associated lumbosacral skin findings predicted the presence of underlying spinal anomalies.CONCLUSIONSThe prevalence of tethered cord syndrome among children with sacrococcygeal dimples was, for the first time, revealed to be higher than previously thought. MRI and supplemental urodynamic studies may be indicated for children with sacrococcygeal dimples to identify patients with symptomatic TSC.


Neurosurgery ◽  
1987 ◽  
Vol 20 (2) ◽  
pp. 281-285 ◽  
Author(s):  
Edward C. Benzel ◽  
Theresa A. Hadden ◽  
James Edward Coleman

Abstract We evaluated 42 patients with neurological deficits after civilian gunshot wounds to the spine. Thirty-five of these patients (the study population presented here) received their initial and follow-up care at Louisiana State University Medical Center in Shreveport over a 4-year period. Each patient had incurred a single gunshot wound to the spinal cord or cauda equina with an accompanying neurological deficit. The patient population was divided into three groups. Group 1 patients had incurred a complete motor and sensory loss below the injury (20 patients (57%)). Group 2 patients had incurred incomplete spinal cord injuries (9 patients (26%)), whereas Group 3 patients had cauda equina injuries (6 patients (17%)). Myelography was performed for all Group 2 and 3 patients as well as Group 1 patients in whom the trajectory of the bullet did not explain a higher level of neurological injury (3 patients (15%)). A decompressive operation was performed in the patients whose myelography showed neural compression. Three patients in Group 1 (15%), 5 patients in Group 2 (56%), and 5 Group 3 patients (83%) underwent operation. All 3 Group 1 patients who underwent operation had some improvement of nerve root function postoperatively. All operated Group 2 and 3 patients had improvement of myelopathic or radicular function postoperatively. All began improving within several days of operation, implying a cause and effect relationship. None of the 17 nonoperated Group 1 patients improved neurologically, whereas 3 of the 4 nonoperated Group 2 patients improved. The single nonoperated Group 3 patient improved neurologically. It is concluded that patients with incomplete neurological injuries after civilian gunshot wounds to the spine can expect radicular or myelopathic improvement. Decompressive operation is indicated in selected cases with unexpected radicular injuries or incomplete myelopathic injuries with myelographic evidence of neural compression. A stepwise improvement in neurological function over that expected without operation should be realized in these cases.


VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.


1984 ◽  
Vol 52 (03) ◽  
pp. 253-255 ◽  
Author(s):  
C Isles ◽  
G D O Lowe ◽  
B M Rankin ◽  
C D Forbes ◽  
N Lucie ◽  
...  

SummaryWe have previously shown abnormalities of haemostasis suggestive of intravascular coagulation in patients with malignant hypertension, a condition associated with retinopathy and renal fibrin deposition. To determine whether such abnormalities are specific to malignant hypertension, we have measured several haemostatic and haemorheological variables in 18 patients with malignant hypertension (Group 1), 18 matched healthy controls (Group 2), and 18 patients with non-malignant hypertension (Group 3) matched for renal pathology, blood pressure and serum creatinine with Group 1. Both Groups 1 and 3 had increased mean levels of fibrinogen, factor VIIIc, beta-thrombo- globulin, plasma viscosity and blood viscosity (corrected for haematocrit); and decreased mean levels of haematocrit, antithrombin III and platelet count. Mean levels of fast antiplasmin and alpha2-macroglobulin were elevated in Group 1 but not in Group 3. We conclude that most blood abnormalities are not specific to malignant hypertension; are also present in patients with non-malignant hypertension who have similar levels of blood pressure and renal damage; and might result from renal damage as well as promoting further renal damage by enhancing fibrin deposition. However increased levels of fibrinolytic inhibitors in malignant hypertension merit further investigation in relation to removal of renal fibrin.


2020 ◽  
pp. 64-75
Author(s):  
E. Burleva ◽  
O. Smirnov ◽  
S. Tyurin

The purpose of the study was to conduct a comparative assessment of the course of the postoperative period after phlebectomy and thermal ablation in patients with varicose veins of the lower extremities in the system of the great saphenous vein (GSV) with class C2 of chronic venous insufficiency (CVI) — CEAP class C2. Materials and methods: 455 patients (455 limbs) with CEAP class C2. Group 1 (n = 154) received stripping + minimally invasive phlebectomy; Group 2 — endovenous laser ablation (EVLA) of GSV trunk + sclerotherapy of varicose veins; 3 group (n = 150) — radiofrequency ablation (RFA) of the GSV + sclerotherapy. All patients were united by a single tactical solution — the elimination of pathological vertical reflux in GSV. In each group, patients were with similar hemodynamic profile were selected (Group 1 = 63; Group 2 = 61; Group 3 = 61). The course of the postoperative period (from 2 days to 2 months) was compared for pain (visual analog scale — VAS), clinical symptoms of chronic venous insufficiency, degree of satisfaction (Darvall questionnaire), and duration of disability. Statistical processing was carried out using Excel programs for Windows XP, MedCalc® (version 11.4.2.0., Mariakerke, Belgium). Results: Postoperative pain is more pronounced (during day 1 for Group 1–4.0, Group 2–3.0, Group 3–2.0) and more prolonged (up to 4 days) after open surgeries (p < 0.05). The dynamics of the clinical symptoms of CVI (including varicose syndrome and use of compression therapy) could not be fully evaluated in connection with the ongoing sclerotherapy procedures for patients of Groups 2 and 3. Satisfaction of patients with aesthetic aspects was higher than expected in all groups. Reliable statistical differences proved decrease in days of disability (Group 1–14; Group 2–4; Group 3–3) and earlier return to physical activities and work in patients after thermal ablation in comparison with phlebectomy. Conclusion: The study shows that all three methods for eliminating vertical reflux in the GSV can be proposed for a large category of patients with CEAP of class C3 and C2. Medical and social rehabilitation of patients using endovascular thermal ablation technologies proceeds faster, which is beneficial both for the patients and for society.


To identify the prevalence of early pathology of cardiovascular diseases, a survey of 400 200 girls) in the age group 15 and 17 years old was conducted as a part of routine medical of the level of blood pressure (BP) was carried out, with the calculation of the average level pressure on the basis of three separate measurements estimated by percentile tables for a registration of a standard resting ECG in 12 leads. According to the results of the survey, into 3 groups: with an increase in blood pressure above 95 ‰ (group 1 – 16 people), which recorded in males (p<0,05); Group 2 (67 people) – adolescents with a normal blood pressure level and group 3 of adolescents with a decrease in blood pressure below 5 ‰ changes in the form of rhythm and conduction disturbances were noted in almost every a predominance of sinus tachycardia in the first group. In the third group of adolescents, form of ectopic rhythm and pacemaker migration were significantly more frequently only 78 % of adolescents were referred for consultation and in-depth examination by a pediatric cardiologist.


2019 ◽  
Vol 17 (4) ◽  
pp. 354-364
Author(s):  
Hassan Al-Thani ◽  
Moamena El-Matbouly ◽  
Maryam Al-Sulaiti ◽  
Noora Al-Thani ◽  
Mohammad Asim ◽  
...  

Background: We hypothesized that perioperative HbA1c influenced the pattern and outcomes of Lower Extremity Amputation (LEA). Methods: A retrospective analysis was conducted for all patients who underwent LEA between 2000 and 2013. Patients were categorized into 5 groups according to their perioperative HbA1c values [Group 1 (<6.5%), Group 2 (6.5-7.4%), Group 3 (7.5-8.4%), Group 4 (8.5-9.4%) and Group 5 (≥9.5%)]. We identified 848 patients with LEA; perioperative HbA1c levels were available in 547 cases (Group 1: 18.8%, Group 2: 17.7%, Group 3: 15.0%, Group 4: 13.5% and Group 5: 34.9%). Major amputation was performed in 35%, 32%, 22%, 10.8% and 13.6%, respectively. Results: The overall mortality was 36.5%; of that one quarter occurred during the index hospitalization. Mortality was higher in Group 1 (57.4%) compared with Groups 2-5 (46.9%, 38.3%, 36.1% and 31.2%, respectively, p=0.001). Cox regression analysis showed that poor glycemic control (Group 4 and 5) had lower risk of mortality post-LEA [hazard ratio 0.57 (95% CI 0.35-0.93) and hazard ratio 0.46 (95% CI 0.31-0.69)]; this mortality risk persisted even after adjustment for age and sex but was statistically insignificant. The rate of LEA was greater among poor glycemic control patients; however, the mortality was higher among patients with tight control. Conclusion: The effects of HbA1c on the immediate and long-term LEA outcomes and its therapeutic implications need further investigation.


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