Pulmonary function and head lift during spontaneous recovery from pipecuronium neuromuscular block

Abstract

We have studied in seven healthy conscious volunteers the correlation between the electromyographic (EMG) and clinical criteria used to identify adequate recovery from sub-paralysing doses of pipecuronium. Pipecuronium (mean dose 1.88 (range 0.92-3.16) mg) was administered to reach a T4/T1 ratio of 0.5; full recovery to 1.0 was produced in a mean time of 25.3 (14-39) min. During recovery from neuromuscular block, we measured tidal volume, forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) negative inspiratory pressure (NIP), peak expiratory flow rate (PEFR), mid-expiratory flow rate (MEFR) and 5-s head lift. The assessments were started when the train-of-four (TOF) ratio reached 0.5 +/- 0.001 and repeated at each 0.1 +/- 0.001 increase up to a ratio of 1.0. All volunteers showed ptosis and diplopia after the first dose and difficulty in swallowing with subsequent doses. They also experienced a pleasant, relaxing sedative sensation. All could sustain head lift for 5 s at a TOF ratio of 0.5 and higher, except for one subject who could not lift his head only at a ratio of 0.5. There was a statistically significant decrease in FVC, FEV1 and PEFR with a nonsignificant decrease in other pulmonary measurements, except for NIP which only decreased significantly at a ratio of 0.5. These changes are probably of no clinical importance. All the measured respiratory variables returned to control values at a TOF ratio of 0.9.

Reversal of profound vecuronium-induced neuromuscular block under sevoflurane anesthesia: sugammadex versus neostigmine

“…In addition to using the TOF-Watch, neuromuscular recovery was assessed using clinical tests (5-sec head-lift test and a test for general weakness). The 5-second head-lift test may be considered insensitive [10] and inappropriate for the detection of residual block [11], and the test for general muscle weakness has not been formally validated and was intended more as a clinical measurement tool for overall well being. However, these tests were not meant to stand alone but rather to complement the findings of the objective neuromuscular monitoring.…”

Recovery of Neuromuscular Function After Cardiac Surgery: Pancuronium Versus Rocuronium

“…Although the ability to sustain a 5-second head-or leg-lift may occur when TOF ratios of 0.50 are attained (8), some subjects will be unable to perform these tasks until TOF ratios more than 0.80 are reached (7,9). The most sensitive test on physical examination for residual paresis may be the ability to maintain incisor teeth apposition; TOF ratios must exceed 0.85 before subjects can resist a vigorous effort to remove a tongue depressor (7).…”

“…Only one test of residual muscle weakness, a negative inspiratory force of Ϫ20 cm H 2 O, was performed before extubation. A negative inspiratory force of Ϫ20 cm H 2 O can be generated in the presence of a TOF fade ratio as small as 0.5, however (8). An additional limitation was that TOF monitoring was terminated at the start of ventilatory weaning.…”

Intraoperative Acceleromyography Monitoring Reduces Symptoms of Muscle Weakness and Improves Quality of Recovery in the Early Postoperative Period

“…27 In the clinical setting, 71% of patients with TOF ratios less than 0.7 were able to perform a 5-s head lift on arrival to the PACU. 28 In the current investigation, the median number of signs of muscle weakness was 0 in the acceleromyography and control groups at all four measurement times.…”