Efficacy of sugammadex for the reversal of moderate and deep rocuronium-induced neuromuscular block in patients pretreated with intravenous magnesium: a randomized controlled trial.

BACKGROUND: Magnesium enhances the effect of rocuronium. Sugammadex reverses rocuronium-induced neuromuscular block. The authors investigated whether magnesium decreased the efficacy of sugammadex for the reversal of rocuronium-induced neuromuscular block. METHODS: Thirty-two male patients were randomized in a double-blinded manner to receive magnesium sulfate (MgSO4) 60 mg/kg or placebo intravenously before induction of anesthesia with propofol, sufentanil, and rocuronium 0.6 mg/kg. Neuromuscular transmission was monitored using TOF-Watch SX acceleromyography (Organon Ltd., Dublin, Ireland). In 16 patients, sugammadex 2 mg/kg was administered intravenously at reappearance of the second twitch of the train-of-four (moderate block). In 16 further patients, sugammadex 4 mg/kg was administered intravenously at posttetanic count 1 to 2 (deep block). Primary endpoint was recovery time from injection of sugammadex to normalized train-of-four ratio 0.9. Secondary endpoint was recovery time to final T1. RESULTS: Average time for reversal of moderate block was 1.69 min (SD, 0.81) in patients pretreated with MgSO4 and 1.76 min (1.13) in those pretreated with placebo (P = 0.897). Average time for reversal of deep block was 1.77 min (0.83) in patients pretreated with MgSO4 and 1.98 min (0.58) in those pretreated with placebo (P = 0.572). Times to final T1 were longer compared with times to normalized train-of-four ratio 0.9, without any difference between patients pretreated with MgSO4 or placebo. CONCLUSION: Pretreatment with a single intravenous dose of MgSO4 60 mg/kg does not decrease the efficacy of recommended doses of sugammadex for the reversal of a moderate and deep neuromuscular block induced by an intubation dose of rocuronium.

Anesthesia for craniotomy in a patient with previous paralytic polio.

Poliomyelitis remains endemic in many developing nations. Patients may develop residual muscle weakness in one or more limbs after an attack of poliomyelitis in childhood. We report an adult patient who presented for right temporal cortical grid placement. He had childhood poliomyelitis and, while showing no evidence of postpolio syndrome, demonstrated excessive sensitivity to nondepolarizing muscle relaxants and developed prolonged muscle weakness during the postoperative period.

Pharmacokinetics of pancuronium in patients undergoing coronary artery surgery with and without low dose dopamine.

Pancuronium is frequently used in coronary artery surgery, but its pharmacokinetics in these patients are still unknown. It is possible that dopamine, administered to prevent renal impairment induced by the surgery, might promote the elimination of pancuronium. Therefore, the pharmacokinetics of a bolus dose of pancuronium were studied in 2 groups of coronary artery surgery patients, with and without dopamine 2 micrograms/kg/min, administered during and after cardiopulmonary bypass. Dopamine in the administered dose did not influence the systemic haemodynamics. The pharmacokinetic variables in both groups did not differ from those found in an earlier study in healthy normothermic patients. Total renal clearance was not influenced by dopamine, due to post-bypass rebound hyperperfusion in the control group. Pancuronium was shown to be subject to considerable tubular reabsorption, and its elimination was found to be increased during hypothermia. Dopamine increases pancuronium elimination by an increase in glomerular filtration rate. The dopamine-induced decrease in tubular solute reabsorption did not enhance the elimination of pancuronium.

Investigation of pleural effusion: an evaluation of the new Olympus LTF semiflexible thoracofiberscope and comparison with Abram's needle biopsy.

STUDY OBJECTIVES: Recently, pulmonologists have performed thoracoscopy under local anesthesia using rigid thoracoscopes or flexible bronchoscopes. The latter allow greater access within the pleural cavity but are difficult to manipulate. The Olympus LTF semiflexible fiberoptic thoracoscope combines features of both instruments, having a solid body and a flexible terminal section. In the first study with this instrument, we evaluated ease of use and compared diagnostic yield with closed needle biopsy. PATIENTS: Twenty-four patients with pleural effusion were investigated. SETTING: Scottish University Hospital. DESIGN: Thoracoscopy was performed in the bronchoscopy suite after premedication with atropine and papaveretum. Following a standard Abram's needle biopsy, the LTF thoracoscope was inserted through a flexible introducer (Olympus Optical Co Ltd; Tokyo, Japan). The pleura was inspected and biopsy specimens were taken of suspicious areas. RESULTS: The final diagnosis was malignant pleural effusion in 16 of 24 patients. Ten of 16 were positive by Abram's biopsy, giving a sensitivity of 62%. Thirteen of 16 were positive by fiberoptic thoracoscopy, giving an improved sensitivity of 81%. The LTF thoracoscope was easy to use for pulmonologists experienced in rigid thoracoscopy and flexible bronchoscopy. Excellent views of the pleura were obtained from a single entry point. The procedure was well tolerated and no complications were encountered. CONCLUSION: The LTF thoracoscope allows excellent pleural access but a larger biopsy channel (currently 2 mm) might increase the accuracy of diagnosis.

Acute pancreatitis complicating a bone marrow harvest.

A patient developing acute pancreatitis with pseudocyst formation after an uncomplicated bone marrow harvest is reported. The diagnosis was confirmed by elevated serum amylase and lipase, and by CT scan. We suggest that the pancreatitis may have been precipitated by spasm of the sphincter of Oddi secondary to opiates administered as premedication and for pain relief.

Effect of prior administration of a non-depolarising muscle relaxant on the action of suxamethonium in the dog.

The non-depolarising muscle relaxants alcuronium (0.1 mg kg-1), gallamine (1 mg kg-1) and pancuronium (0.06 mg kg-1) were administered to six dogs. At 50 per cent return of neuromuscular activity, as measured by the train-of-four technique, the depolarising muscle relaxant suxamethonium (0.3 mg kg-1) was injected intravenously. At 50 per cent return of neuromuscular activity, atropine and neostigmine were administered to reverse the neuromuscular block. The duration of action of suxamethonium was reduced by each of the non-depolarising muscle relaxants.

The use of meptazinol as a premedication for surgical patients.

The acceptability of a mixture of meptazinol and hyoscine as a surgical premedication was compared with that of an Omnopon-hyoscine combination in a randomized, double-blind trial involving 101 surgical patients. Blood pressure and respiratory rate were significantly reduced to a similar extent by both premedicant combinations, and this may be interpreted as evidence of a satisfactory alleviation of anxiety by both test mixtures. The two mixtures produced a similar degree of sedation, and both were associated with a useful inhibition of salivary secretion. Side-effects were reported in 25% patients in the meptazinol group, and in 28% of those receiving Omnopon, although a number of these effects may be attributable to hyoscine. There was no difference in the pattern of post-operative analgesic requirements between the two groups, and no unfavourable interaction was noted with any of the anaesthetic agents used.

Succinylcholine and intraocular pressure.

Thirty-one patients (61 eyes) had a rise in intraocular pressure averaging 8.2 mm Hg following the use of succinylcholine as a muscle relaxant prior to general anesthesia. Just prior to the start of surgery (an average of 14 minutes following Anectine administration), the tension had returned to the control level. Ten patients (20 eyes) had pancuronium used without succinylcholine. No change in intraocular tension was noted with this agent and pressure remained unchanged at the start of surgery. Work of other investigators, using the "spring back balance" test and strain gauge force measurement to rotate the globe, indicate that the effect of Anectine upon the extraocular muscles may take 20 to 30 minutes to wear off. This is long after the return of intraocular pressure to control values and suggests that monitoring of intraocular tension may not be accurate method of assessing the action of Anectine upon the eye muscles. The mechanism of increased fluid outflow, not muscle relaxation, probably accounts for this lowering of intraocular pressure.

The synergistic effect of two different nondepolarizing muscle relaxants on intraocular pressure.

STUDY OBJECTIVES: To evaluate the synergistic effect of neuromuscular blockade, produced by administering a priming dose of d-tubocurarine before or after pancuronium bromide, on endotracheal intubating conditions, intraocular pressure (IOP), and hemodynamic changes 1 minute following injection of intubating doses. To compare the results with equipotent doses of the individual muscle relaxants administered as a single bolus dose or in divided doses. DESIGN: Randomized study. SETTING: University medical center. PATIENTS: Ninety ASA physical status I and II inpatients (45 males, 45 females) assigned to one of six comparable groups (A-F). INTERVENTIONS: One hour after premedication, either normal saline (Groups A and B) or a priming dose of either d-tubocurarine (Groups C and F) or pancuronium (Groups D and E) was given intravenously (IV). Three minutes later, anesthesia was induced with 6 mg/kg of 2.5% thiopentone i.v. Then an intubating dose of pancuronium (Groups A, C, and E) or d-tubocurarine (Groups B, D, and F) was administered. The total dose given was equal to d-tubocurarine 0.4 mg/kg or pancuronium 0.07 mg/kg. Patients were intubated 1 minute after injection of an intubating dose of either relaxant. MEASUREMENTS AND MAIN RESULTS: IOP was measured with a Perkins applanation tonometer and blood pressure (BP) by a sphygmomanometer. Heart rate was derived from the electrocardiogram. Intubating conditions were scored according to given intubation criteria. Measurements were obtained at different times before and after intubation. In those patients given only one muscle relaxant for intubation either divided into priming and intubating doses or preceded by normal saline (Groups A, B, E, and F), there was a significant increase in IOP in response to intubation as compared with baseline (p < 0.05). In contrast, when d-tubocurarine was used as the priming drug for pancuronium blockade (Group C), IOP was significantly reduced in response to intubation, despite a concomitant increase in BP (p < 0.05). No significant change in IOP was observed when pancuronium was used as the priming drug for d-tubocurarine blockade (Group D). Although good to excellent intubating conditions were reported in Groups C and D, poor intubating conditions were reported when the priming muscle relaxant was the same as the relaxant used to intubate. CONCLUSIONS: A smooth, rapid-sequence intubation with a concomitant reduction in IOP as required for open-eye, full-stomach patients can be achieved with a judicious mixture of nondepolarizing muscle relaxants as described for d-tubocurarine and pancuronium in Groups C and D.

A simple, cheap, effective and safe procedure for general anesthesia.

A simplified, safe and flexible technique of anesthesia, based on a limited number of relatively cheap drugs, and allowing ventilation with air, was applied to 60 patients undergoing operations of at least 60 minutes' duration. The required depth of hypnosis was produced by intravenous diazepam or gamma-OH, whilst droperidol and fentanyl provided a satisfactory degree of sedation and analgesia. Pancuronium bromide was used for muscle relaxation. Spontaneous respiration was resumed immediately after postoperative use of nalorphine and neostigmine. The anesthetic course was smooth and predictable, with cardiovascular stability and an uneventful postoperative recovery. Emphasis is laid on the suitability of this procedure on the Battle Field or in Developing Countries, and on its safety (no toxic volatile liquids). (Acta anaesth. belg., 1976, 27, 25-34).

Muscle relaxants for out-patient procedures.

The requirements for muscle relaxation in out-patient anesthesia are: a short total relaxation enabling the induction of an endotracheal tube followed by a period of 15-20 minutes of clinical relaxation. Reversal should be spontaneous. The new short acting muscle relaxants vecuronium and atracurium enable such a procedure, provided small doses are used (0.045 mg/kg for vecuronium or 0.2 mg/kg for atracurium. These small doses require a longer waiting time before intubation is easily performed (5 min for vecuronium and 6 min for atracurium). Spontaneous reversal of these small doses is achieved within 20-30 minutes. Potentiation of the relaxation by inhalational agents is not recommended.

Clinical use of vecuronium (ORG NC 45) in balanced anesthesia. Comparison with pancuronium.

In 2 groups of 25 patients 0.1 mg/kg vecuronium (Org NC 45) or pancuronium, according to a randomised basis, was injected during balanced anesthesia (thiopental, fentanyl, dehydrobenzperidol and N2O). Intubation conditions 120 seconds after injection were satisfactory. After intubation, a heart rate increase was present with pancuronium (p less than 0.01), but not with vecuronium (difference: p less than 0.05); heartrate decreased 15 and 30 minutes after injection of vecuronium (p less than 0.01). The clinical duration of action of vecuronium was 32.7 +/- 2.4 min (Mean +/- SEM) and of pancuronium 73.5 +/- 4.8 min (p less than 0.01). Successive maintenance doses of 0.025 mg/kg of vecuronium had a duration of action of 23.1 +/- 1.7, 26.8 +/- 2.1, 27.6 +/- 4.0 and 24.0 +/- 2.8 min (diff. NS), showing no cumulative activity. The duration of action of identical doses of pancuronium were 56.9 +/- 3.1, 52.1 +/- 7.2 and 61.3 +/- 17.6 min (diff. NS), values nearly +/- 220% above those of vecuronium (p less than 0.01). Reversion of neuromuscular blockade after vecuronium with small amounts of neostigmine was clinically adequate.

Slow EEG-power spectra correlate with haemodynamic changes during laryngoscopy and intubation following induction with fentanyl or sufentanil.

We studied nociception-associated arousal following laryngoscopy and intubation in patients scheduled for elective open heart surgery, using EEG power spectra and hemodynamics. Either fentanyl (7 micrograms/kg; n = 30) or sufentanil (1 microgram/kg; n = 30) were given in a randomized fashion to induce anesthesia in heavily premedicated patients, followed by pancuronium bromide (100 micrograms/kg). EEG-power spectra (delta, theta, alpha, beta) as well as mean arterial blood pressure (MAP) and heart rate (HF) were measured at the following end-points: before the induction of anesthesia (control), 1 and 10 minutes after laryngoscopy and intubation (L & I). Linear regression analysis was computed to determine which of the EEG power spectra was most sensitive to detect insufficient blockade of nociceptive-related arousal when correlated with haemodynamics. In the fentanyl group the change in HF closely correlated with the decrease of power in the slow delta- and theta-domain (r2 = 0.98 and r2 = 0.89 respectively) of the EEG. The change in MAP also closely correlated with a decrease in the slow delta- and theta-domain (r2 = 0.97 and r2 = 0.99 respectively). There was little correlation in regard to spectral edge frequency (SEF) and HF and MAP changes (r2 = 0.36 and r2 = 0.12 respectively). In the sufentanil group the change in HF correlated closely with an increase of power in the fast alpha and a decrease in the slow theta-domain (r2 = 0.91 and r2 = 0.98 respectively) of the EEG. The changes in MAP closely correlated with an increase in the fast alpha-band a decrease in the slow theta-domain (r2 = 0.98 and r2 = 0.73 respectively). Also there was little correlation of SEF with HF and MAP changes (r2 = 0.09 and r2 = 0.02 respectively). Among the EEG-spectra, reduction of power in the slow delta- and theta-bands are the most sensitive parameters to determine insufficient antinociception of opioids commonly used for the induction in cardiac anesthesia. Increase of power in the alpha-band seems to be closely correlated with cortical reactivation and reduction of hypnosis, while a reduction of power especially in the deltabut more so in the theta-band of the EEG reflects nociception related arousal.

[Anaphylactic shock caused by pancuronium and vecuronium]. / Choc anaphylactique au pancuronium et au vécuronium.

A case is reported of anaphylactic shock due to vecuronium occurring in a patient who had already had such a shock, due then to pancuronium, during a previous general anaesthesia. The need for a full immuno-allergological investigation, the occasional efficiency of the anti-histamine premedication, and crossed allergies between muscle relaxants are stressed. It is noted that an anaphylactic shock can be seen on first using a new molecule, as the patient can have been sensitized to it by other muscle relaxants. This case was the first to be described of an anaphylactic shock due to vecuronium bromide.

[Induction-intubation sequence in neuroanesthesia. Usefulness of vecuronium in fractionated doses]. / Secuencia de inducción-intubación en neuroanestesia. Utilidad del vecuronio en dosis fraccionadas.

Muscular relaxant vecuronium bromide (Norcuron R, Organon Teknika Española, S.A.) was administered to 20 patients undergoing intracranial surgery with general anesthesia at a dose of 0.01 mg/kg weight followed by 0.1 mg/kg (intubation dose) four minutes later. Two minutes after the second dose and under careful manual mechanical ventilation with O2 100%, a laryngoscopy was performed to evaluate the conditions for intubation. Mean arterial pressure, heart rate, PaO2, and PaCO2 were measured at baseline and immediately before laryngoscopy. Neuromuscular function was monitored observing the response to a train of four stimuli applied on the cubital nerve. During the operation a continuous infusion of vecuronium at a rate of 1 microgram/kg/min was maintained. Conditions for intubation were excellent in 18 patients and good in two cases. Mean heart rate and PaCO2 did not show significant variations. In contrast, during prelaryngoscopy mean arterial pressure decreased and PaO2 increased with respect to the baseline values. During surgery all patients showed a good clinical relaxation. Thus, we believe that vecuronium is a good muscular relaxant agent, safe, and effective to be used in neurosurgery.

[Is it necessary to discontinue captopril before heart surgery?]. / Faut-il arrêter le captopril avant l'opération en chirurgie cardiaque?

Interaction between kininase II and anaesthesia is not well described. Twenty two patients treated by kininase II for congestive heart failure are studied during anaesthesia for cardiovascular surgery. A first group of seventeen homogeneous hemodynamic data are reported. High cardiac index contrasts with severe clinical cardiac failure. A second group of inhomogeneous patients are separately described. Vasoconstrictor can be codified in the situation of low systemic resistance with high cardiac index. Preoperative treatment can be continued, under requirement of hemodynamic monitoring.