Neuromuscular block in patients 80 years and older: a prospective, controlled study

Abstract Background An increasing number of patients older than 80 years are undergoing anesthesia, but little information is available regarding pharmacodynamic effects of myorelaxants in this population. This study aims to compare the time course of rocuronium neuromuscular block in patients ≥ 80 years with those of younger adults. Methods Under total intravenous anesthesia with propofol and sufentanil, time course of a bolus of rocuronium 0.6 mg/kg neuromuscular block was assessed with acceleromyography in patients ≥ 80 and in patients 20–50 years old. Onset time, clinical duration, duration until 90% and 100% recovery of baseline were determined. Results Data from 32 patients were analyzed, 16 were ≥ 80 years and 16 were 20–50 years old. Demographic data are shown in Table 1. In the group ≥ 80, onset time was 190 s ± 46 s compared to 123 s ± 40 s in the group 20–50, P < 0.001 and the clinical duration was 52 [48–69.5] min and 36 [34–41] min, respectively, P < 0.001. Duration to 90% recovery of baseline was 77.5 [71–88.5] min and duration to 100% recovery of baseline was 91.2 [82.2–98] min in patients ≥ 80 years and the corresponding values in the patients 20–50 years old were 53.5 [49–55.5] min and 59.5 [56.5–70.25] min, respectively, P < 0.001. Conclusion Compared to younger adults rocuronium shifted in patients ≥ 80 years from a rapid onset, intermediate acting compound to a slower onset, long-acting compound. Trial registration ClinicalTrials.gov identifier: NCT03551652 (29/05/2018).

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The Influence of Mild Hypothermia on the Pharmacokinetics and Time Course of Action of Neostigmine in Anesthetized Volunteers

Anesthesiology ◽

10.1097/00000542-200207000-00013 ◽

2002 ◽

Vol 97 (1) ◽

pp. 90-95 ◽

Cited By ~ 28

Author(s):

Tom Heier ◽

David Clough ◽

Peter M. C. Wright ◽

Manohar L. Sharma ◽

Daniel I. Sessler ◽

...

Keyword(s):

Time Course ◽

Mechanical Response ◽

Mild Hypothermia ◽

Neuromuscular Block ◽

Onset Time ◽

Volume Of Distribution ◽

Maximum Effect ◽

Surface Cooling ◽

Duration Of Action ◽

Course Of Action

Background The pharmacokinetics, maximum effect, and time course of action of neostigmine were studied in seven human volunteers. Methods Each volunteer was studied twice, during both normothermia and hypothermia. Anesthesia was induced with 30 microg/kg alfentanil and 3 mg/kg propofol, and was maintained with 60-70% nitrous oxide and 0.7-0.9% isoflurane. The mechanical response of the adductor pollicis to train-of-four stimulation of the ulnar nerve was recorded, and central body temperature maintained stable at either less than 34.5 degrees C or greater than 36.5 degrees C by surface cooling or warming. Before neostigmine administration, a stable 5% twitch height was obtained by an infusion of vecuronium, and the infusion rate remained unchanged thereafter. Neostigmine, 70 microg/kg, was then infused over 2 min, and blood samples for estimation of neostigmine concentrations were collected at intervals for 240 min. Results With hypothermia, the central volume of distribution of neostigmine decreased by 38%, and onset time of maximum effect increased (4.6 vs. 5.6 min). Hypothermia did not change the clearance (696 ml/min), maximum effect, or duration of action of neostigmine. Conclusions The efficacy of neostigmine as an antagonist of vecuronium-induced neuromuscular block is not altered by mild hypothermia.

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Dose-Response of Rocuronium Bromide in Children Anesthetized with Propofol

Anesthesiology ◽

10.1097/00000542-199712000-00016 ◽

1997 ◽

Vol 87 (6) ◽

pp. 1368-1372 ◽

Cited By ~ 27

Author(s):

Rex L. Woolf ◽

Mark W. Crawford ◽

Shu May Choo

Keyword(s):

Dose Response ◽

Time Course ◽

Neuromuscular Block ◽

Linear Regression Analysis ◽

Rapid Onset ◽

Rocuronium Bromide ◽

Response Data ◽

Course Of Action ◽

Recovery Profile ◽

Supramaximal Stimulation

Background The aim of this study was to determine the potency of rocuronium during propofol/fentanyl/N2O anesthesia in children and to compare the time course of action of rocuronium at doses of two and three times the ED95 with that of succinylcholine. Methods Rocuronium (120, 160, 200, or 240 microg/kg) was administered to 48 children aged 2-10 yr. Neuromuscular block was assessed by monitoring the electromyographic response of the adductor digiti minimi to supramaximal stimulation of the ulnar nerve at 2 Hz for 2 s every 10 s. Potency was determined by log-probit transformation and least-squares linear regression analysis of dose and response. In a second group of 30 children, the onset and recovery profile of rocuronium at doses of two and three times the ED95 was compared with that of succinylcholine (2 mg/kg). Results Values for ED50 and ED95 were 210 +/- 24 and 404 +/- 135 microg/kg, respectively. The time to 90% neuromuscular block after 1.2 mg/kg rocuronium (three times the ED95), 33 +/- 5 s (mean +/- SD), did not differ significantly from that after succinylcholine, at 30 +/- 7 s; however, both were significantly less than that after 0.8 mg/kg rocuronium, 46 +/- 8 s (P < 0.05). The time to 25% recovery from 1.2 microg/kg rocuronium, 41 +/- 13 min, was approximately 50% greater than that after 0.8 mg/kg, at 27 +/- 6 min (P < 0.001), and eight times greater than that after succinylcholine, at 5.2 +/- 1.9 min (P < 0.001). Conclusions Both 1.2 mg/kg rocuronium (three times the ED95) and 2 mg/kg succinylcholine provide 90% neuromuscular block within 45 s in 95% of children. The present dose-response data support the use of rocuronium at a dose of 1.2 mg/kg when rapid onset and intermediate-duration neuromuscular block are needed in children.

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ORG 9487 Neuromuscular Block at the Adductor Pollicis and the Laryngeal Adductor Muscles in Humans

Anesthesiology ◽

10.1097/00000542-199706000-00011 ◽

1997 ◽

Vol 86 (6) ◽

pp. 1300-1305 ◽

Cited By ~ 46

Author(s):

Bertrand Debaene ◽

Thomas Lieutaud ◽

Valerie Billard ◽

Claude Meistelman

Keyword(s):

Neuromuscular Block ◽

Onset Time ◽

Rapid Onset ◽

Adductor Pollicis ◽

Vocal Cords ◽

Onset Of Action ◽

Duration Of Action ◽

Adductor Pollicis Muscle ◽

Org 9487 ◽

Adductor Muscles

Background ORG 9487 is a new steroidal nondepolarizing muscle relaxant with a rapid onset of action. This study was designed to determine the neuromuscular blocking profile of ORG 9487 at the adductor muscles of the larynx and the adductor pollicis. Methods In 30 adults, anesthesia was induced with propofol (2-5 mg/kg) and fentanyl (2-3 microg/kg). After train-of-four stimulation, the block of the laryngeal adductor muscles was evaluated by measuring the pressure changes in the cuff of the tracheal tube placed between the vocal cords, and the force of the contraction of the adductor pollicis was measured with a force transducer. Patients were randomly allocated to receive ORG 9487 at intravenous bolus doses of 0.75, 1.5 or 2 mg/kg (n = 10 in each group). Results Time to peak effect was significantly shorter at the vocal cords than at the adductor pollicis muscle (P < 0.001). Onset time at the vocal cords was 62 +/- 16 s, 62 +/- 13 s, and 52 +/- 14 s (mean +/- SD) after doses of 0.75, 1.5, and 2 mg/kg, respectively (not significant). Onset time at the adductor pollicis muscle was 126 +/- 33 s, 96 +/- 20 s, and 82 +/- 21 s after 0.75, 1.5, and 2 mg/kg doses, respectively (P < 0.001). Maximum block was significantly less intense at the vocal cords than at the adductor pollicis muscle (69 +/- 15% vs. 94 +/- 4% after 0.75 mg/kg; 86 +/- 7% vs. 97 +/- 4% after 1.5 mg/kg; and 91 +/- 5% vs. 99 +/- 1% after 2 mg/kg). After 1.5 mg/kg duration to 25%, recovery was 3.7 +/- 2.2 min versus 10.2 +/- 2.5 min at the vocal cords and the adductor pollicis muscle, respectively, and 75% recovery occurred at 9.7 +/- 3.7 min at the vocal cords and at 18.3 +/- 5.2 min at the adductor pollicis muscle. Conclusions ORG 9487 has a rapid onset of action at the laryngeal adductor and the adductor pollicis muscles. Onset and duration of action are faster at the vocal cords than at the adductor pollicis muscle. However, the maximum block obtained at the laryngeal muscles was less than at the adductor pollicis, regardless of the dose of ORG 9487.

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Molar Potency Is Predictive of the Speed of Onset of Neuromuscular Block for Agents of Intermediate, Short, and Ultrashort Duration

Anesthesiology ◽

10.1097/00000542-199902000-00016 ◽

1999 ◽

Vol 90 (2) ◽

pp. 425-431 ◽

Cited By ~ 55

Author(s):

Aaron F. Kopman ◽

Monica M. Klewicka ◽

David J. Kopman ◽

George G. Neuman

Keyword(s):

Short Duration ◽

Neuromuscular Block ◽

Onset Time ◽

Inverse Correlation ◽

Peak Effect ◽

American Society ◽

The Times ◽

Long Acting ◽

End Tidal ◽

Speed Of Onset

Background The times to peak effect of rocuronium, vecuronium, cisatracurium, mivacurium, and succinylcholine were evaluated to confirm that the correlation between potency and onset time observed for long-acting relaxants also held for drugs of intermediate and short duration. Methods The authors recruited 99 patients classified as American Society of Anesthesiologists physical status score 1 or 2 for the study. After anesthesia was induced, tracheal intubation was accomplished without relaxants. Anesthesia was maintained with nitrous oxide and 3% or 4% end-tidal desflurane plus intravenous narcotic supplementation. The evoked electromyographic response to single stimuli administered at 0.10 Hz was recorded continuously. Drug doses were selected to produce approximately 95% twitch depression. If peak twitch depression did not fall in the range of 90% to 98%, the patient was excluded from the study. The time to 50% to 90% of peak effect was plotted as a function of the administered dose. Results There was no difference in the onset profiles of mivacurium and vecuronium, or in the time to 50% of peak effect between succinylcholine and rocuronium. For all other parameters, onset times ranked as follows: succinylcholine < rocuronium < vecuronium-mivacurium < cisatracurium (P < 0.05). When the log of the ED95 in micromoles per kilogram for all five drugs was plotted against the log of onset time to 50% peak effect, the R2 value for the best fit line was more than 0.98. Conclusions The inverse correlation between the molar potency and speed of onset previously described for agents of long duration also applies to nondepolarizing agents of intermediate and short duration. The onset time of succinylcholine also appears to be compatible with this relation.

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COMPARISON OF TRAMADOLAS AN ADJUVANT TO INTRATHECAL ISOBARIC LEVOBUPIVACAINE FOR ELECTIVE LOWER LIMB SURGERIES UNDER SPINAL ANESTHESIA

10.36106/8422685 ◽

2021 ◽

pp. 53-55

Author(s):

Shiv Shankar Jangid ◽

S. P. Chittora ◽

Mohammed Mishal ◽

Akil Hussain

Keyword(s):

Lower Limb ◽

Demographic Data ◽

Onset Time ◽

Motor Blockade ◽

Time Duration ◽

Sensory Blockade ◽

Ethical Committee Approval ◽

The Mean ◽

Long Acting ◽

Mean Time

Background: Long acting local anesthetics are used in subarachnoid block to increase the duration of anesthesia. Adjuvants are added to improve the duration of analgesia. The objective of this study was to evaluate the efcacy of tramadol as an intrathecal adjuvant to levobupivacaine in terms of duration of analgesia, onset of sensory blockade, onset of motor blockade, and duration of motor blockade. Methodology: After obtaining the Institutional Ethical Committee approval and informed consent, sixty patients posted for infraumbilical surgeries were recruited. Randomization was done using a sealed envelope technique. Patients were divided into two groups: LTreceived 2.5 ml of 0.5% isobaric levobupivacaine with tramadol 25 mg (0.5 ml) and LS received 2.5 ml of 0.5% isobaric levobupivacaine with 0.5 ml of normal saline. Duration of analgesia, onset of sensory blockade, and onset and duration of motor blockade were recorded. Results: There was no statistical difference in demographic data between the two groups. The mean onset time of sensory blockade in Group LS was 7.17±3.07 min and for Group LT was 8.53 ± 2.47 min, which was not statistically signicant between two groups (P = 0.064). The mean onset time of motor blockade in Group LS was 9.76 ± 3.18 min and for Group LT was 11.23 ± 2.47 min, which was statistically signicant between the two groups (P = 0.050). The mean time duration of analgesia in Group LS was 265.60± 39.18 min and for LT was 304.30 ± 24.88 min. There was mild prolongation of analgesia in Group LT, but it was statistically signicant (P <0.001). The mean duration of motor blockade in Group LS was 197.93 ± 4.41 min and Group LT was 236.20 ± 33.89 min, which was statistically signicant between the two groups (P <0.001). Conclusion: Tramadol as an adjuvant to isobaric intrathecal levobupivacaine does prolong analgesia signicantly.

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