Postoperative Upper Airway Obstruction After Recovery of the Train of Four Ratio of the Adductor Pollicis Muscle from Neuromuscular Blockade

Abstract

Anesthetics, and even minimal residual neuromuscular blockade, may lead to upper airway obstruction (UAO). In this study we assessed by spirometry in patients with a train-of-four (TOF) ratio >0.9 the incidence of UAO (i.e., the ratio of maximal expiratory flow and maximal inspiratory flow at 50% of vital capacity [MEF50/MIF50] >1) and determined if UAO is induced by neuromuscular blockade (defined by a forced vital capacity [FVC] fade, i.e., a decrease in values of FVC from the first to the second consecutive spirometric maneuver of > or =10%). Patients received propofol and opioids for anesthesia. Spirometry was performed by a series of 3 repetitive spirometric maneuvers: the first before induction (under midazolam premedication), the second after tracheal extubation (TOF ratio: 0.9 or more), and the third 30 min later. Immediately after tracheal extubation and 30 min later, 48 and 6 of 130 patients, respectively, were not able to perform spirometry appropriately because of sedation. The incidence of UAO increased significantly (P < 0.01) from 82 of 130 patients (63%) at preinduction baseline to 70 of 82 patients (85%) after extubation, and subsequently decreased within 30 min to values observed at baseline (80 of 124 patients, 65%). The mean maximal expiratory flow and maximal inspiratory flow at 50% of vital capacity ratio after tracheal extubation was significantly increased from baseline (by 20%; 1.39 +/- 1.01 versus 1.73 +/- 1.02; P < 0.01), and subsequently decreased significantly to values observed at baseline (1.49 +/- 0.93). A statistically significant FVC fade was not present, and a FVC fade of > or =10% was observed in only 2 patients after extubation. Thus, recovery of the TOF ratio to 0.9 predicts with high probability an absence of neuromuscular blocking drug-induced UAO, but outliers, i.e., persistent effects of neuromuscular blockade on upper airway integrity despite recovery of the TOF ratio, may still occur.

Comparison of the use of thoracic epidural analgesia in a wake patients versus general anesthesia undergoing intra-abdominal surgery

“…Baburajan et al (13) reported that with the awake thoracic epidural method, sufficient analgesic activity is provided and there is no need for analgesic supplement. In other literatures, similar results were reported (8,11,13). In our study, in three patients in the epidural group and in seven patients from the general group the intraoperative fentanyl was required and this difference was not regarded as statistically significant.…”

“…Residual neuromuscular blockade is a predictor of postoperative pulmonary complication, causing alveolar hypoventilation and gastric regurgitation with consequent bronchoaspiration (8). Elrazek et al (9) applied the awake TEA method in two patients for whom cholecystectomy and sigmoid colon operations were planned and reported that the haemodynamic and respiratory parameters were stable and sufficient muscle relaxation was provided.…”

Neuromuscular Blockade, Bariatric Surgeon Satisfaction, and Quality of Patient Recovery

“…In the post-anesthesia care unit (PACU), postoperative residual curarization (PORC) may be particularly problematic due to the possibility of critical respiratory events (10). Although the incidence is low, PORC may lead to respiratory insufficiency, impaired upper airway function (11), and increased risk of aspiration (12). This, in turn, is also associated with significantly delayed discharges (13).…”

Acceleromyography at the Flexor Hallucis Brevis Muscle Underestimates Residual Neuromuscular Blockade

“…Neuromuscular monitoring of the upper limb is used to determine when swallowing and respiratory functions have returned to pre-neuromuscular blockade levels [1][2][3][4][5]. To prevent postoperative respiratory complications, TOFR of the upper limb should recover to > 0.9 before extubation [2,[6][7][8][9][10].…”

“…To prevent postoperative respiratory complications, TOFR of the upper limb should recover to > 0.9 before extubation [2,[6][7][8][9][10]. However, it is difficult to monitor a patient's upper limb responses to neuromuscular blockade if their arms are not accessible because they are involved with the surgery or tucked at their side.…”