Biomedical subjects

J A Alvarez-Gómez

Publications and source records attributed to J A Alvarez-Gómez.

3 recordsLinked to original sources

PubMed2005

The cuff method: a pilot study of a new method of monitoring neuromuscular function.

BACKGROUND: A new method of monitoring neuromuscular blockade based on a modified blood pressure cuff that incorporates stimulating electrodes was compared with mechanomyography (MMG) ('gold standard'). METHODS: Forty adults and 20 children (ASA I-II) underwent neuromuscular blockade monitoring on the contralateral arms and on the same arm using the new cuff method and MMG. Only train-of-four (TOF) ratios > 0.1 and T(1) heights > 0 were studied. Supramaximal stimulation was also assessed. A device based on a PC with an analogue-to-digital conversion card was used to control and synchronize MMG and the cuff method. The agreement between both methods was assessed using the statistical method of Bland and Altman. RESULTS: When TOF ratios were >0.7, the bias between the two methods was -0.04 with the limits of agreement ranging from -0.21 to -0.12 (95% CI -0.06 to -0.02). The T(1) > 0 heights bias was -0.01 with the limits of agreement ranging from -0.26 to 0.24 (95% CI -0.02 to -0.003). The sensitivity of the cuff method was 88%, with a specificity of 85% and an accuracy of 86%. CONCLUSION: This pilot study indicates that the cuff method could be useful to monitor neuromuscular blockade according to the bias and limits of agreement compared with MMG, particularly when the degree of blockade was evaluated by TOF ratios > 0.7. The new cuff method is easy and simple to use. However, further studies in a larger number of patients are necessary to confirm these favourable preliminary results.

Adolescent↗

PubMed1997

[Rocuronium].

Rocuronium is a new nondepolarizing neuromuscular blocking agent (NDNMBA) that has recently been introduced for clinical use. Its main advantage over other such agents is its rapid onset of action, which may lead to its use as the relaxant of choice when rapid intubation is required. An additional advantage is that, unlike other amino-steroidal NDNMBAs, rocuronium does not produce active metabolites. The potency of rocuronium is five times lower than that of vecuronium and its half life at its place of effect is shorter. Selectivity for the laryngeal muscle system is greater, possibly explaining the rapid onset observed. Hemodynamic stability, along with the absence of histamine release even at doses as high as 4 to 5 ED95, allow it to be used in high risk patients. Successful use has been reported in emergency surgery in patients with full stomachs, in cesarean deliveries, in cardiovascular surgery, and in liver, kidney and other transplants. Rocuronium administered in repeated doses or in continuous infusion provides adequate muscle relaxation over the required period, with predictable reversibility of effects.

Age Factors↗

PubMedDate not supplied

[Speed of intubation using a new neuromuscular blocker. Rocuronium bromide (ORG 9426)].

OBJECTIVES: To compare intubation conditions and neuromuscular parameters, patency time, maximum level of block, time and clinical duration of effect for rocuronium bromide 0.6 mg/kg (ORG 9426) versus equally potent doses of vecuronium and atracurium under similar experimental conditions. PATIENTS AND METHODS: Sixty patients were divided into three groups of twenty. Intubation conditions were scored on a scale of 3-12 points based on relaxation of the vocal cords, presence of cough and ease of laryngoscopy after 60 or 90 sec. Neuromuscular parameters were obtained by integrated electromyography of the thenar and hypothenar muscle structure, evoked by supramaximal stimuli of the cubital nerve in train of four (2 Hz in 2 sec). The shape of the electrocardiographic curve, heart rate and mean arterial pressure measured non-invasively were recorded throughout the surgical procedure. RESULTS: Means of onset times and times of effect for rocuronium (33 and 135 sec) were significantly lower than those obtained with vecuronium and atracurium. Clinical duration, free of hemodynamic changes, was similar in the three groups. Rocuronium produces excellent intubation conditions 60 sec after administration, although at this point peripheral muscle block was only partial. Rocuronium may be superior to other neuromuscular blockers available today as a result of the speed with which it affords excellent intubation conditions.

Adult↗