Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Neuromuscular Blockade”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources
PubMed1992

No effect of neuromuscular blockade on the temporomandibular joint position during general anesthesia.

In an attempt to determine the role that nondepolarizing neuromuscular blocking agents play in the intraoperative position of the mandibular condyle, occlusal checkbites were taken on 10 patients under general anesthesia before and after neuromuscular blockade with vecuronium. These checkbites were compared to checkbites taken preoperatively. Nondepolarizing neuromuscular blocking agents had no effect on condylar position recordings during general anesthesia. The results demonstrate that general anesthesia itself is by far the dominant factor in intraoperative condylar position changes.

Anesthesia, General↗
PubMed1997

Priming with rocuronium accelerates the onset of neuromuscular blockade.

STUDY OBJECTIVE: To investigate the effects of priming rocuronium on the time course of neuromuscular blockade. DESIGN: Prospective, controlled, randomized clinical study. SETTING: University teaching hospital. PATIENTS: 42 ASA physical status I and II patients undergoing peripheral surgery with general anesthesia. INTERVENTIONS: Following a standardized propofol-fentanyl induction, patients in Group 1 (n = 21) received a priming dose of rocuronium 0.06 mg/kg followed two minutes later by an intubating dose of rocuronium 0.54 mg/kg. Patients in Group 2 (n = 21) received a saline placebo injection followed two minutes later by rocuronium 0.6 mg/kg. Anesthesia was maintained with isoflurane and nitrous oxide 60% in oxygen. MEASUREMENTS AND MAIN RESULTS: Neuromuscular function was assessed at the wrist using mechanomyography with a single-twitch mode of stimulation at a frequency of 1 Hz until tracheal intubation and at 0.1 Hz thereafter. The times from injection of the intubating dose of rocuronium until 95% suppression of the twitch tension (onset time), recovery of twitch tension to 25% of control (clinical duration of action), and the time from 25% to 75% spontaneous recovery of twitch tension (recovery index) were recorded. The trachea was intubated at 95% depression of the twitch tension and the intubating conditions were graded using a 3-point scale. The onset times with priming rocuronium (34 +/- 6 s) were significantly shorter (p < 0.01) than those without priming (59 +/- 14 s). The intubation conditions were similar in the two groups; however, the intubating times with priming were significantly shorter. The clinical duration of action and the recovery index did not differ significantly between the two groups. CONCLUSIONS: Priming rocuronium decreased the onset times and thus, the intubating times without increasing the clinical duration of action or recovery index.

Adult↗
PubMed1994

[Potentiation of pancuronium induced neuromuscular blockade by nitrous oxide].

To evaluate in man the potentiation by nitrous oxide of the neuromuscular blockade produced by pancuronium, pancuronium 0.025, 0.035, 0.049 or 0.068 mg.kg-1 was given during thiamylal-fentanyl anesthesia with and without nitrous oxide, and the evoked electromyography (EMG) of hypothenar muscle was measured. In the group receiving nitrous oxide the ED50 and ED95 were 0.0359 and 0.0691 mg.kg-1. In the group not receiving nitrous oxide, these values were 0.0389 and 0.0849 mg.kg-1. The dose-response curve (DRC) constructed from log-probit transformation for the group not receiving nitrous oxide shifted to the right for 10.3% (P < 0.05). It was also revealed that the magnitude of the blockade was influenced by dose, gender, nitrous oxide, lean body mass and body surface area by the multiple regression analysis. DRS for the female patients shifted to the left, and the differences between both sexes seemed to decrease in the group receiving nitrous oxide. It is concluded that the results of the present study appears to be similar to those obtained in the previous study on vecuronium using EMG.

Adolescent↗
PubMed1990

[Influence of small doses of vecuronium and pancuronium on succinylcholine-induced neuromuscular blockade].

The effects of pretreatments with vecuronium (VB) and pancuronium (PB) on succinylcholine (SCC)-induced neuromuscular blockade were evaluated in 266 patients using electromyographic responses to train-of-four (TOF) ulnar nerve stimulation repeated every 20 seconds. Seventy-five patients served as the control group and received 1 mg.kg-1 SCC without pretreatment with VB or PB. Other 191 patients were divided into three groups according to the type and dosage of pretreatment as follows: VB 20 micrograms.kg-1, VB 14 micrograms.kg-1 and PB 20 micrograms.kg-1. Five minutes after each pretreatment. SCC 1 mg.kg-1 was administered intravenously. All patients were intubated after SCC injection and then anesthesia was maintained with nitrous oxide and enflurane. Among pretreatment groups, the maximal amplitude response to TOF stimuli and TOF ratio were depressed most by 20 micrograms.kg-1 VB and least by 20 micrograms.kg-1 PB at the time of SCC administration. All pretreatments delayed the onset time from SCC injection to maximal blockade compared with that of control group. Maximal blockade induced by SCC was significantly less in VB 20 micrograms.kg-1 group than that in other pretreatment and control groups. The duration of action of SCC was shortened by pretreatments with two dosages of VB but prolonged by PB pretreatment. TOF ratio during the recovery phase was depressed in all pretreatment groups than that in control group. It is demonstrated that a non-depolarizing muscle relaxant, VB has relatively potent antagonistic action on SCC-induced effects, although another potent agent, PB exerts antagonistic action only slightly.

Adult↗
PubMed1990

Effect of d-tubocurarine pretreatment on succinylcholine twitch augmentation and neuromuscular blockade.

Subparalyzing doses of d-tubocurarine (dTC) given before succinylcholine decrease the duration of neuromuscular blockade. In animal preparations, they also abolish succinylcholine-induced twitch augmentation, defined as a greater-than-maximal contraction in response to a single stimulus. To determine quantitatively the effect of dTC on succinylcholine potency and on twitch augmentation in humans, 60 adult patients, ASA physical status I or II, were assigned randomly to receive either 0.05 mg/kg of dTC or saline 2 min before induction of anesthesia with fentanyl and thiopental. Train-of-four stimulation was applied every 12 s to the ulnar nerve and the force of contraction of the adductor pollicis muscle was measured. One minute after induction of anesthesia, 0.15, 0.20, 0.25, 0.35, or 0.50 mg/kg of succinylcholine was given. The height of the first twitch (T1) reached 121% +/- 6% (mean +/- SEM) of control without dTC, and was virtually abolished by dTC pretreatment (105% +/- 1%, P less than 0.01). Twitch augmentation was more noticeable with lower doses of succinylcholine, and was not observed in the response to the fourth stimulus of the train of four (T4). The potency of succinylcholine was decreased by approximately one-half in the dTC-pretreated groups. The ED50 was 0.27 +/- 0.04 mg/kg without dTC and 0.50 +/- 0.06 mg/kg with dTC (P less than 0.002). The corresponding values for ED90 were 0.51 +/- 0.07 and 1.02 +/- 0.12 mg/kg, respectively (P less than 0.02). The ED95 values were 0.63 +/- 0.09 and 1.28 +/- 0.15 mg/kg, respectively (P less than 0.02). The slopes of the regression lines did not deviate significantly from parallelism.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

The effect of neuromuscular blockade on human fetal heart rate and its variation.

OBJECTIVE: To determine the effect of neuromuscular blockade on fetal heart rate and its variation. DESIGN: Case control study. SETTING: Tertiary referral fetal medicine unit in a London teaching hospital. SUBJECTS: Forty women with rhesus iso-immunisation requiring an intravascular fetal blood transfusion between 28 and 34 weeks gestation. INTERVENTION: Intravascular injection of pancuronium to the fetus prior to fetal blood transfusion in 20 cases. MAIN OUTCOME MEASURES: Comparison between the group receiving pancuronium and the control group with regard to differences in perceived fetal activity and computer derived numerical indices of fetal heart rate and fetal heart rate variation after fetal blood transfusion. RESULTS: After transfusion in the control group, there were fewer perceived fetal movements, a small reduction in fetal heart rate but no differences in number of fetal heart rate accelerations or measures of fetal heart rate variation. In the study group, pancuronium produced no change in fetal heart rate despite a virtual abolition of perceived fetal movements and fetal heart rate accelerations. Measures of fetal heart rate variation were reduced by 60%. Comparison of the pre- to post-transfusion changes between the two groups showed significant differences for all fetal heart rate indices. CONCLUSION: Fetal activity accounts for more than half the measured variation of the human fetal heart rate.

Blood Transfusion, Intrauterine↗
PubMedDate not supplied

[Effect of sevoflurane on the neuromuscular blockade produced by continuous mivacurium infusion ].

OBJECTIVE: To evaluate the effect of sevoflurane on a neuromuscular block from mivacurium in continuous infusion. PATIENTS AND METHODS: Fourteen ASA I-II patients receiving general anesthesia for orthopedic procedures on the knee. The neuromuscular block was monitored by acceleromyography in the adductor pollicis muscle after stimulation of the cubital nerve. Anaesthesia was induced with propofol and remifentanil. After orotracheal intubation, mivacurium was given in continuous infusion adjusted to obtain a stable submaximal block defined as a variation in the block of 3% more or less for 10 minutes (first response on a train of four [T1] between 40% and 60% of the calibrated value). Values for T1, the T4/T1 ratio (TR) and temperature over the thenar eminence were recorded at 3 moments: control moment (infusion of mivacurium and sevoflurane at an expired fraction of 1.5% for 30 minutes) and post-sevoflurane moment (perfusion of mivacurium and sevoflurane at an expired fraction of 0% for 15 minutes). Statistical analysis was by analysis of variance and post-hoc contrast (Tukey). RESULTS: Results are expressed as means with standard error between parentheses. We found that values at T1(%) and TR(%) were significantly lower at the sevoflurane moments (T1 = 43.11 [1]; TR = 25.68 [1]) and the post-sevoflurane moment (T1 = 36.29 [2]; TR = 25.06 [2]) than at the control moment (T1 = 53.18 [1]; TR = 38.93 [1]) (P < .05). T1 was significantly lower at the post-sevoflurane moment than at the sevoflurane moment (P < .05) but TR did not differ significantly. CONCLUSION: Sevoflurane causes a significant increase in the neuromuscular block maintained by mivacurium in continuous infusion and the increase lasts at least 15 minutes after the halogenated agent is cleared from blood.

Adult↗
PubMed2002

National practice with assessment and monitoring of neuromuscular blockade.

The Food and Drug Administration, drug manufacturers, and critical care experts recommend using peripheral nerve stimulators (PNSs) to monitor depth of blockade when administering neuromuscular blocking agents (NMBAs). This study evaluates critical care nurses' practices regarding use of PNSs, identifies problems associated with their use, and determines other methods of assessing level of blockade to guide medication titration. Of respondents to a survey, 75% reported administering NMBAs for long-term use in their critically ill patients. In facilities using NMBAs, 63% monitored blockade level with aPNS. Because of practice disparities and monitoring problems, further education and research are needed to ensure adequate monitoring during NMBA administration.

Attitude of Health Personnel↗
PubMed1994

Structural components of beta-eudesmol essential for its potentiating effect on succinylcholine-induced neuromuscular blockade in mice.

beta-Eudesmol, a sesquiterpenoid alcohol isolated from Atractylodes lancea rhizoma, potentiates the neuromuscular blocking effect of succinylcholine (SuCh). The potentiating effect is greater in diabetic muscles than in normal ones. To identify the structural components of beta-eudesmol contributing to this action, we examined the potentiating effect of newly synthesized tertiary alcohols related to beta-eudesmol in phrenic nerve-diaphragm muscle preparations of normal and alloxan-diabetic mice. Potentiating effects were exhibited by cyclohexylidene derivatives but not by cyclohexanone or cyclohexanol derivatives. The compound 2-(3-hydroxy-3-methylbutyl)cyclohexylidene exhibited a potentiating effect, but 3-(3-hydroxy-3-methylbutyl)cyclohexylidene did not. These results indicate that both the presence of an exo-methylene attached to a cyclohexane ring and the distance between the exo-methylene and the hydroxy group in beta-eudesmol are involved in the potentiating effect on SuCh-induced neuromuscular blockade.

Animals↗
PubMed1984

Potentiation of neuromuscular blockade by verapamil.

The effects of intravenous (iv) verapamil (0.01 to 1.0 mg/kg) on the constant neuromuscular block produced by an iv infusion of either pancuronium or succinylcholine were studied on the indirectly stimulated gastrocnemius and tibialis-anterior muscles of the rabbit anesthetized with halothane in oxygen. Verapamil alone (n = 6) had no significant effect. However, the drug did significantly potentiate the 50% twitch depression of the gastrocnemius muscle produced by a constant iv infusion of either pancuronium (n = 5) or succinylcholine (n = 5) to 36 +/- 6% and 45 +/- 1% of control, respectively. This effect of verapamil occurred with doses of 0.1 mg/kg for pancuronium and 0.01 mg/kg for succinylcholine; these doses of verapamil were the lowest which produced a significant effect. In contrast, verapamil had no significant effect on the progression of the neuromuscular blockade of either the gastrocnemius or tibialis-anterior muscles produced by alpha-bungarotoxin (n = 5). Verapamil also significantly prolonged the P-R interval of the ECG from a control value of 71 +/- 2 ms to 78 +/- 3 ms at a dose of 0.1 mg/kg and to 93 +/- 6 ms at a dose of 0.3 mg/kg. The possible mechanisms of the neuromuscular actions of verapamil are discussed and it is concluded that verapamil can produce potentiation of either pancuronium- or succinylcholine-induced neuromuscular block at doses within the therapeutic range.

Animals↗
PubMed2005

A priming technique accelerates onset of neuromuscular blockade at the laryngeal adductor muscles.

PURPOSE: Priming is a known technique to accelerate onset of neuromuscular blockade (NMB). Its effect on NMB of the larynx has not been studied yet. METHODS: We compared a priming technique with a bolus application of rocuronium on the onset of NMB at the laryngeal adductor and the adductor pollicis muscles (AP). In 30 female patients, after induction of anesthesia a tube with a surface electrode was placed into the trachea prior to the administration of any neuromuscular blocking agent to monitor electromyography (EMG) of the laryngeal adductor muscles. Neuromuscular monitoring consisted of EMG of the laryngeal adductor muscles and the left AP. Patients were randomized into two groups. After transcutaneous stimulation of the recurrent laryngeal nerve and ulnar nerve, a bolus of rocuronium 0.6 mg x kg(-1) (Bolus group) or a priming dose of rocuronium 0.06 mg x kg(-1) followed by rocuronium 0.54 mg x kg(-1) three minutes later (Priming group) were injected. Lag time, onset 90%, onset time and peak effect of NMB were recorded and compared; a P < 0.05 was considered significant. RESULTS: The onset 90% and onset time measured at the laryngeal adductor muscles (onset: 44.7 +/- 7.4 vs 74.0 +/- 23.8 sec) and at the AP (onset: 105.4 +/- 29.9 vs 139.2 +/- 51.5 sec) were significantly shorter in the Priming group than in the Bolus group. Within groups, the onset times were significantly shorter at the laryngeal muscles in comparison to AP. CONCLUSION: Our results indicate that a priming technique with rocuronium significantly accelerates the onset of NMB at the laryngeal adductor muscles. Our results further support the use of rocuronium as an alternative to succinylcholine for rapid sequence induction.

Adult↗
PubMed1989

beta-eudesmol (a main component of Atractylodes lancea)-induced potentiation of depolarizing neuromuscular blockade in diaphragm muscles of normal and diabetic mice.

Potentiating effects of beta-eudesmol on neuromuscular blockade were investigated in phrenic nerve-diaphragm muscles of normal and alloxan-diabetic mice. Pretreatment with beta-eudesmol potentiated the blocking effects of succinylcholine to a greater extent in diabetic muscles than in normal ones. This effect was saturated after 30-min pretreatment in normal muscles. Further potentiation was observed after 60-min pretreatment in diabetic muscles. These results suggest that beta-eudesmol modifies the sensitivity of diabetic mice to depolarizing blockers so that they have a higher susceptibility to these compounds.

Animals↗
PubMed1988

Use of the post-tetanic count to monitor recovery from intense neuromuscular blockade in children.

The post-tetanic count was investigated as a method of monitoring intense neuromuscular blockade in children. One of five myoneural blockers (atracurium, vecuronium, pancuronium, tubocurarine or alcuronium) was given to groups of six children during nitrous oxide-oxygen-halothane anaesthesia. During recovery, the first post-tetanic response always preceded the first train-of-four response. The interval between the appearance of the first post-tetanic response and the first train-of-four response was typically 5-10 min for the intermediate-acting agents vecuronium and atracurium, and 20-30 min for the long-acting agents pancuronium, alcuronium and tubocurarine. A post-tetanic count of 6 with alcuronium and tubocurarine, or 7 with vecuronium, atracurium and pancuronium indicated that recovery of the first train-of-four response was imminent.

Anesthesia, Inhalation↗
PubMed2001

Comparison of cisatracurium-induced neuromuscular blockade between immediate postpartum and nonpregnant patients.

STUDY OBJECTIVES: To evaluate and compare cisatracurium-induced neuromuscular blockade and intubating conditions between immediate postpartum (PP) and nonpregnant (NP) patients. DESIGN: Prospective control study. SETTINGS: University Hospital Center. PATIENTS: 44 ASA physical status I and II patients: 22 immediate postpartum (PP) patients (<48 hours after delivery) scheduled for elective postpartum tubal ligation and 22 nonpregnant (NP) patients (>40 weeks from prior pregnancy) scheduled for elective gynecological procedures. INTERVENTIONS: General anesthesia was induced intravenously (IV) with thiopental sodium 5 mg/kg, fentanyl 2.0 to 3.0 ug/kg, midazolam 0.015 to 0.025 mg/kg, and cisatracurium 0.2 mg/kg. Evoked electromyographic responses of the adductor pollicis muscle were obtained by supra-maximal train-of-four stimulation of the ulnar nerve every ten seconds via surface electrodes at the wrist. Intubation was attempted at 90 s after completion of cisatracurium administration and again at 120 seconds if the first attempt was unsuccessful. The intubating anesthesiologist assessed the intubating conditions with four variables: jaw relaxation, vocal cord immobility and exposure, patient/diaphragmatic movement, and overall intubating impression. Intraoperative anesthetic was maintained with 30% oxygen, 70% nitrous oxide, and 1% end-tidal isoflurane, as tolerated. Patient temperature was maintained at 35.5 degrees to 37.5 degrees Celsius (C), and end-tidal carbon dioxide at 30 to 36 mmHg. MEASUREMENTS AND MAIN RESULTS: The mean onset times to 50%, 90%, and maximal T(1) depression and mean time to 25% T(1) recovery in the PP group (68 +/- 19 sec, 110 +/- 26 sec, 147 +/- 32 sec, 60 +/- 6 min) were significantly less than those in the NP group (80 +/- 17 sec, 131 +/- 28 sec, 181 +/- 44 sec, 69 +/- 12 min), respectively (p < 0.05). All patients were successfully intubated on the first attempt at 90 seconds. 91% of the NP group and 81% of the PP group had excellent overall intubating conditions. CONCLUSIONS: This is the first published control study to compare the effects of cisatracurium between NP and PP patients. The results suggest that the mean onset time and clinical duration of cisatracurium are significantly shorter in immediate postpartum patients than those in nonpregnant female patients.

Adult↗
PubMed2004

Prolonged neuromuscular blockade as a result of malnutrition-induced pseudocholinesterase deficiency.

Mivacurium is a short-acting neuromuscular blocking drug, ideal for short surgical procedures. The brief duration of action depends on rapid hydrolysis by plasma cholinesterase. An inherited or acquired deficiency of plasma cholinesterase can prolong the effect of mivacurium. We present an unusual case of unanticipated postoperative apnea following mivacurium administration, as a result of acquired plasma cholinesterase deficiency, in a patient with previous uneventful exposure to both mivacurium and suxamethonium (succinylcholine).

Aged↗
PubMed1995

Clindamycin-induced neuromuscular blockade.

The purpose of this article is to report the case of a patient who developed prolonged neuromuscular block after a large dose of clindamycin (2400 mg). A 58-yr-old, 65 kg woman with severe rheumatoid arthritis was admitted for wrist arthrodesis. After d-tubocurarine (3 mg) and fentanyl (1.5 micrograms.kg-1), anaesthesia was induced with thiopentone (4 mg.kg-1) followed by succinylcholine (1.5 mg.kg-1) and was maintained with N2O in O2 and isoflurane (0.75-1.0% end tidal) and ventilation was controlled. No further neuromuscular relaxants were given although full return of neuromuscular activity in response to train-of-four and 100 Hz tetanic stimulation was observed after succinylcholine. An overdose of clindamycin (2400 mg, instead of the intended 600 mg) was given i.v. soon after the start of surgery. At the end of surgery, 75 min later, the patient made no attempt at spontaneous ventilation, was unresponsive to painful stimuli and naloxone (0.2 mg i.v.) was ineffective. Controlled ventilation was continued in the Recovery Room where neuromuscular testing showed a train-of-four ratio of 0.27 which improved to only 0.47 five minutes after calcium chloride (1.5 mg.kg-1 i.v.), and to 0.62 after edrophonium (20 mg) and neostigmine (2 mg). Nine hours later the patient began to cough, the TOF had returned to 1.0 and two hours later the trachea was extubated and spontaneous ventilation was resumed. Large doses of clindamycin can induce profound, long-lasting neuromuscular blockade in the absence of non-depolarizing relaxants and after full recovery from succinylcholine has been demonstrated.

Anti-Bacterial Agents↗
PubMed1995

Sedation and pain control in the critically ill patient maintained on continuous neuromuscular blockade.

Anxiety and pain pose a challenge in the management of the critically ill patient on continuous neuromuscular blockade. Without adequate treatment, anxiety can further complicate a patient's already compromised state. Benzodiazepines, haloperidol, and propofol provide options for anxiolysis in these patients. Despite the fact that the physiologic consequences of pain can be devastating, the undertreatment of pain remains an issue. The opioid agonists constitute the agents of choice for parenteral analgesia in the critically ill.

Procedural Sedation↗
PubMed1986

Profound atracurium induced neuromuscular blockade. A comparison of evoked reversal with edrophonium or neostigmine.

Speed of reversal of profound atracurium induced neuromuscular blockade following edrophonium (0.5 or 1.0 mg/kg) or neostigmine (0.04 or 0.08 mg/kg) was measured using the train-of-four pattern of nerve stimulation. In all patients adequate clinical reversal was present when the ratio of the strength of the fourth to the first twitch (T4 ratio) was 0.5. Both doses of edrophonium were associated with a significantly faster speed of reversal than the smaller dose of neostigmine (p less than 0.05 in both cases). However, the larger dose of neostigmine was associated with a reversal time approaching that of edrophonium. Possible explanations for these findings are discussed in terms of contemporary theories of neuromuscular pharmacology.

Adult↗