Administration Of Neuromuscular Blocking Agents Research Articles

Neuromuscular Blockade in Geriatric Patients

The administration of neuromuscular blocking agents has been used in anesthesia for decades and continues to play an important role in modern anesthesia. Special patient populations, such as very young or very old patients, require adapted use. The following article discusses the specifics of neuromuscular blocking agents administration in geriatric patients.

Pediatric Intraoperative Electromyographic Responses at the Adductor Pollicis and Flexor Hallucis Brevis Muscles: A Prospective, Comparative Analysis.

Peripheral nerve stimulation with a train-of-four (TOF) pattern can be used intraoperatively to evaluate the depth of neuromuscular block and confirm recovery from neuromuscular blocking agents (NMBAs). Quantitative monitoring can be challenging in infants and children due to patient size, equipment technology, and limited access to monitoring sites. Although the adductor pollicis muscle is the preferred site of monitoring, the foot is an alternative when the hands are unavailable. However, there is little information on comparative evoked neuromuscular responses at those 2 sites. Pediatric patients undergoing inpatient surgery requiring NMBA administration were studied after informed consent. Electromyographic (EMG) monitoring was performed simultaneously in each participant at the hand (ulnar nerve, adductor pollicis muscle) and the foot (posterior tibial nerve, flexor hallucis brevis muscle). Fifty patients with a mean age of 3.0 ± standard deviation (SD) 2.9 years were studied. The baseline first twitch amplitude (T1) of TOF at the foot (12.46 mV) was 4.47 mV higher than at the hand (P <.0001). The baseline TOF ratio (TOFR) before NMBA administration and the maximum TOFR after antagonism with sugammadex were not different at the 2 sites. The onset time until the T1 decreased to 10% or 5% of the baseline value (T1) was delayed by approximately 90 seconds (both P =.014) at the foot compared with the hand. The TOFR at the foot recovered (TOFR ≥0.9) 191 seconds later than when this threshold was achieved at the hand (P =.017). After antagonism, T1 did not return to its baseline value, a typical finding with EMG monitoring, but the fractional recovery (maximum T1 at recovery divided by the baseline T1) at the hand and foot was not different, 0.81 and 0.77, respectively (P =.68). The final TOFR achieved at recovery was approximately 100% and was not different between the 2 sites. Although this study in young children demonstrated the feasibility of TOF monitoring, interpretation of the depth of neuromuscular block needs to consider the delayed onset and the delayed recovery of TOFR at the foot compared to the hand. The delay in achieving these end points when monitoring the foot may impact the timing of tracheal intubation and assessment of adequate recovery of neuromuscular block to allow tracheal extubation (ie, TOFR ≥0.9).

Neuromuscular Blocking Agent Use in Critical Care Transport Not Associated With Intubation

ObjectiveVariable indications exist for neuromuscular blocking agents (NMBAs) in the critical care transport setting beyond facilitation of intubation. MethodsThis retrospective cohort study included adult patients (≥ 18 years) who underwent critical care transport from July 1, 2020, to May 2, 2023, and received NMBAs during transport that was not associated with intubation. The primary outcome was the indication for NMBA administration. Secondary outcomes included the characterization of NMBA use, mean Richmond Agitation Sedation Scale score before NMBA administration, sedation strategy used, and continuation of NMBAs within 48 hours of hospital admission. ResultsOne hundred twenty-six patients met the inclusion criteria. The most common indication for NMBA administration was ventilator dyssynchrony (n = 71, 56.4%). The majority of patients received rocuronium during transport (n = 113, 89.7%). The mean pre-NMBA Richmond Agitation Sedation Scale score was −3.7 ± 2.4. The most common sedation strategy was a combination of continuous infusion and bolus sedatives (76.2%). One hundred (79.4%) patients had sedation changes in response to NMBA administration. Seventy-two (57.1%) received NMBAs during the first 48 hours of their intensive care unit admission. ConclusionNMBAs were frequently administered for ventilator dyssynchrony and continuation of prior therapy. Optimization opportunities exist to ensure adequate deep sedation and reassessment of NMBA indication.

Expiratory Muscle Activity Counteracts Positive End-Expiratory Pressure and Is Associated with Fentanyl Dose in Patients with Acute Respiratory Distress Syndrome.

Rationale: Hypoxemia during mechanical ventilation might be worsened by expiratory muscle activity, which reduces end-expiratory lung volume through lung collapse. A proposed mechanism of benefit of neuromuscular blockade in acute respiratory distress syndrome (ARDS) is the abolition of expiratory efforts. This may contribute to the restoration of lung volumes. The prevalence of this phenomenon, however, is unknown. Objectives: To investigate the incidence and amount of end-expiratory lung impedance (EELI) increase after the administration of neuromuscular blocking agents (NMBAs), clinical factors associated with this phenomenon, its impact on regional lung ventilation, and any association with changes in pleural pressure. Methods: We included mechanically ventilated patients with ARDS monitored with electrical impedance tomography (EIT) who received NMBAs in one of two centers. We measured changes in EELI, a surrogate for end-expiratory lung volume, before and after NMBA administration. In an additional 10 patients, we investigated the characteristic signatures of expiratory muscle activity depicted by EIT and esophageal catheters simultaneously. Clinical factors associated with EELI changes were assessed. Measurements and Main Results: We included 46 patients, half of whom showed an increase in EELI of >10% of the corresponding Vt (46.2%; IQR, 23.9-60.9%). The degree of EELI increase correlated positively with fentanyl dosage and negatively with changes in end-expiratory pleural pressures. This suggests that expiratory muscle activity might exert strong counter-effects against positive end-expiratory pressure that are possibly aggravated by fentanyl. Conclusions: Administration of NMBAs during EIT monitoring revealed activity of expiratory muscles in half of patients with ARDS. The resultant increase in EELI had a dose-response relationship with fentanyl dosage. This suggests a potential side effect of fentanyl during protective ventilation.

Comparison of Intubating Conditions with Succinylcholine Versus Rocuronium in the Prehospital Setting

Objective Rapid sequence intubation (RSI) is frequently performed by emergency medical services (EMS). We investigated the relationship between succinylcholine and rocuronium use and time until first laryngoscopy attempt, first-pass success, and Cormack-Lehane (CL) grades. Methods We included adult patients for whom prehospital RSI was attempted from July 2015 through June 2022 in a retrospective, observational study with pre-post analysis. Timing was verified using recorded defibrillator audio in addition to review of continuous ECG, pulse oximetry, and end-tidal carbon dioxide waveforms. Our primary exposure was neuromuscular blocking agent (NMBA) used, either rocuronium or succinylcholine. Our prespecified primary outcome was the first attempt Cormack-Lehane view. Key secondary outcomes were first laryngoscopy attempt success rate, timing from NMBA administration to first attempt, number of attempts, and hypoxemic events. Results Of 5,179 patients in the EMS airway registry, 1,475 adults received an NMBA while not in cardiac arrest. Cormack-Lehane grades for succinylcholine and rocuronium were similar: grade I (64%, 59% [95% CI 0.64–1.09]), grade II (16%, 21%), grade III (18%, 16%), grade IV (3%, 3%). The median interval from NMBA administration to start of the first attempt was 57 s for succinylcholine and 83 s for rocuronium (mean difference 28 [95% CI 20–36] seconds). First attempt success was 84% for succinylcholine and 83% for rocuronium. Hypoxemic events were present in 25% of succinylcholine cases and 23% of rocuronium cases. Conclusions Prehospital use of either rocuronium or succinylcholine is associated with similar Cormack-Lehane grades, first-pass success rates, and rates of peri-intubation hypoxemia.

Intraoperative electromyographic monitoring in children using a novel pediatric sensor.

Train-of-four (TOF) monitoring is essential in optimizing perioperative outcomes as a means to assess the depth of neuromuscular blockade and confirm recovery following the administration of neuromuscular blocking agents (NMBAs). Quantitative TOF monitoring has been limited in infants and children primarily due to lack of effective equipment. The current study evaluates a novel electromyography (EMG)-based TOF monitor with a recently developed pediatric-sized self-adhesive sensor in infants and children. Consented pediatric patients undergoing inpatient surgery requiring the administration of NMBAs were enrolled. The EMG electrode was placed along the ulnar nerve on the volar aspect of the distal forearm. The muscle action potentials from the adductor pollicis muscle were recorded throughout surgery at 20-second intervals. Data from the monitor's built-in memory card were later retrieved and analyzed. The final study cohort included 51 patients who ranged in age from 0.2 to 7.9 years and in weight from 4.2 to 36.0 kilograms. Thirty patients weighed less than 15 kgs. Supramaximal stimulus current intensity (mA) at a pulse width of 200 μsec was 30 mA in 8%; 40 mA in 29%; 50 mA in 16%; and 60 mA in 20% of the patients. Supramaximal stimulus current intensity (mA) at a pulse width of 300 μsec was 50 mA in 4%; 60 mA in 24%. The muscle action potential baseline amplitude was 8.7 ± 3.3 mV and recovered to 7.2 ± 3.7 mV after antagonism of neuromuscular blockade. The average baseline TOF ratio was 100 ± 3% and recovered to 98 ± 7% after antagonism of neuromuscular blockade. No technical issues were noted with application of the sensor or subsequent use of the monitor. Neuromuscular monitoring can be performed intraoperatively in pediatric patients who are less than 8 years of age using a novel commercially available EMG-based monitor with a recently developed pediatric sensor. The novel sensor allows use of an EMG-based monitor in infants and children in whom acceleromyography or subjective (visual) observation of the TOF response may not be feasible. Automatic detection of neuromuscular stimulating parameters (supramaximal current intensity level, baseline amplitude of the muscle action potential) was feasible in pediatric patients of all sizes including those weighing less than 15 kilograms or when there was limited access to the extremity being monitored.

ROCURONIUM BROMIDE – ESMERON

&lt;div&gt;&lt;p&gt;Repeated neuromuscular-blocking agent administration lengthens the duration of action, and intraoperative use of high doses of neuromuscular-blocking agent may compromise respiratory security. We tested the main hypothesis that intermediate-acting neuromuscular-blocking agents are dose dependently associated with the risk of postoperative respiratory complications in a hospital-based registry study that took place between January 2022 and June 2022 on 70 patients that we worked with who received these medications. Additionally, we looked at the relationship between respiratory problems and the dose of neostigmine used to reverse neuromuscular blockers. We assessed the impact of proper neostigmine reversal on respiratory complications post hoc. Compared to low doses, high doses of neuromuscular-blocking drugs were linked to a higher risk of postoperative respiratory complications. A dose-dependent increase in the risk of postoperative respiratory complications was linked to neostigmine. According to post hoc analysis, the dose-dependent relationship between neuromuscular-blocking drugs and respiratory complications was eliminated by the proper neostigmine reversal. The risk of postoperative respiratory complications was dose-dependently correlated with the use of neuromuscular-blocking drugs. The risk of respiratory complications increased dose-dependently after neostigmine reversal. The exploratory data analysis, however, indicates that the proper use of neostigmine, guided by the results of the monitoring of neuromuscular transmission, can help eliminate the postoperative respiratory complications brought on by the use of neuromuscular-blocking drugs. For newborns and small infants, rocuronium should be administered in lower doses.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;&lt;span&gt;Keywords: &lt;/span&gt;&lt;/strong&gt;&lt;span&gt;respiratory complications, Esmeron, neostigmine, surgery, anesthetic, intubation, etc.&lt;/span&gt;&lt;/p&gt;&lt;/div&gt;

Effects of depth of neuromuscular blockade on the BIS-guided propofol requirement: A randomized controlled trial.

Background:Deep neuromuscular blockade is considered beneficial for improving the surgical space condition during laparoscopic surgery. Adequacy of the surgical space condition may affect the anesthetists’ decision regarding titration of depth of anesthesia. We investigated whether deep neuromuscular blockade reduces the propofol requirement under bispectral index monitoring compared to moderate neuromuscular blockade.Methods:Adult patients undergoing elective laparoscopic colorectal surgery were randomly allocated to a moderate or deep group. A train-of-four count of 1–2 in the moderate group, and a post-tetanic count of 1–2 in the deep group, were maintained by continuous infusion of rocuronium. The induction and maintenance of anesthesia were achieved by target-controlled infusion of propofol and remifentanil. The dose of propofol was adjusted to maintain the bispectral index in the range of 40–50. The remifentanil dose was titrated to maintain the systolic blood pressure to within 20% of the ward values.Results:A total of 82 patients were included in the analyses. The mean±SD dose of propofol was 7.54 ± 1.66 and 7.42 ± 1.01 mg·kg−1·h−1 in the moderate and deep groups, respectively (P = .104). The mean±SD dose of remifentanil was 4.84 ± 1.74 and 4.79 ± 1.77 μg kg−1 h−1 in the moderate and deep groups, respectively (P = .688). In comparison to the moderate group, the deep group showed significantly lower rates of intraoperative patient movement (42.9% vs 22.5%, respectively, P = .050) and additional neuromuscular blocking agent administration (76% vs 53%, respectively, P = .007). Postoperative complications, including pulmonary complications, wound problems and reoperation, were not different between the two groups.Conclusion:Deep neuromuscular blockade did not reduce the bispectral index-guided propofol requirement compared to moderate neuromuscular blockade during laparoscopic colon surgery, despite reducing movement of the patient and the requirement for a rescue neuromuscular blocking agent.Trial registration:Clinicaltrials.gov (NCT03890406)

Risk factors for difficult Laryngeal Mask Airway LMA-Supreme™ (LMAS) placement in adults: a multicentric prospective observational study in an Italian population.

Supraglottic airway devices (SADs) are precious tools for airway management in both routine and rescue situations; few studies have analyzed the risk factors for their difficult insertion. The aim of this study was to identify the risk factors for difficult insertion for a specific SAD, the Laryngeal Mask Airway LMA-Supreme™ (LMAS). This was a prospective multicentric observational study on a cohort of Italian adult patients receiving general anesthesia for elective surgery. The possible causes of difficulty in LMAS placement (difficulty in insertion or unsatisfactory ventilation) were identified based on literature and on the opinion of international airway management experts. A dedicated datasheet was prepared to collect patients' data, including anthropometric-parameters and parameters for the prediction of difficult airway management, as well as technical choices for the use of LMAS. Data were analyzed to discover the risk factors for difficult LMAS placement and the association between each risk factor and the proportion of incorrect positioning was evaluated through the relative risk and its confidence interval. Four hundred thirty-two patients were enrolled; seventy required two or more attempts to insert the LMAS; nine required a change of strategy. At multivariate analysis, the following factors were significantly associated with difficult LMAS placement: Mallampati III-IV with either phonation or not; inter-incisor distance < 3 cm; reduced neck mobility; no administration of neuromuscular blocking agents (NMBAs). The alignment of the laryngeal and pharyngeal axes seems to facilitate the procedure, together with NMBA administration; on the contrary, Mallampati grade III-IV are associated with difficult LMAS placement.

Neuromuscular Blocking Agents for ARDS: A Systematic Review and Meta-Analysis.

Studies evaluating neuromuscular blocking agents (NMBAs) in the management of ARDS have produced inconsistent results in terms of their effect on mortality. The purpose of this systematic review and meta-analysis was to evaluate differences in mortality comparing subjects with ARDS who received NMBA to those who received placebo or usual care. We searched Ovid, MEDLINE, Embase, CINAHL, Cochrane, Scopus, and Web of Science for randomized controlled trials evaluating administration of NMBAs in subjects with ARDS. We included 6 studies (N = 1,558 subjects) from 1,814 abstracts identified by our search strategy. The use of early, continuous-infusion NMBAs reduces the risk of short-term (ie, 21-28-d) mortality (relative risk 0.71 [95% CI 0.52-0.98], P = .030, I 2 = 60%) in subjects with ARDS but does not reduce the risk of long-term (ie, 90-d) mortality (relative risk 0.81 [95% CI 0.64-1.04], P = .10, I 2 = 54%). NMBAs decreased the risk of barotrauma (relative risk 0.55 [95% CI 0.35-0.85], P = .008, I 2 = 0%) and pneumothorax (relative risk 0.46 [95% CI 0.28-0.77], P = .003, I 2 = 0%) compared to control. In subjects with ARDS, early use of NMBAs improves oxygenation, reduces the incidence of ventilator-induced lung injury, and decreases 21-28-d mortality, but it does not improve 90-d mortality. NMBAs should be considered for select patients with moderate-to-severe ARDS for short durations.

Pre-hospital emergency anaesthesia in the United Kingdom: an observational cohort study

BackgroundUp to one in eight trauma patients arrive at a hospital with a partially or completely obstructed airway. The UK National Institute for health and Care Excellence (NICE) practice guidelines recommend that trauma patients requiring anaesthesia for definitive airway management receive this care within 45 min of an emergency call, preferably at the incident scene. How frequently this target is achieved remains unclear. We assessed the recorded time to pre-hospital emergency anaesthesia after trauma across UK helicopter emergency medical service (HEMS) units. MethodsWe retrospectively recorded time to pre-hospital emergency anaesthesia across all 20 eligible UK HEMS units (comprising 52 enhanced care teams) from April 1, 2017 to March 31, 2018. Times recorded for emergency notification, dispatch, arrival, and neuromuscular blocking agent administration were analysed. ResultsHEMS undertook 1755 pre-hospital emergency anaesthetics for trauma across the UK during the study period. There were 1176/1755 (67%) episodes undertaken by helicopter response teams during daylight hours. The median time to pre-hospital emergency anaesthesia was 55 min (inter-quartile range: 45–70); anaesthesia within 45 min of the initial emergency call was achieved in 25% cases. Delayed dispatch time (>9 min) was associated with fewer patients receiving pre-hospital anaesthesia within 45 min (odds ratio: 7.7 [95% confidence intervals: 5.8–10.1]; P<0.0001). ConclusionsThe time to achieve pre-hospital emergency anaesthesia by UK HEMS frequently exceeds the recommended 45 min target. Reducing the time to dispatch of emergency medical teams may impact on the delivery of pre-hospital emergency anaesthesia.

Neuromuscular blockers in the acute respiratory distress syndrome: A meta-analysis.

BackgroundThe effects of neuromuscular blocking agents (NMBAs) on adult patients with acute respiratory distress syndrome (ARDS) remain unclear. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate its effect on mortality.MethodsWe searched the Cochrane (Central) database, Medline, Embase, the Chinese Biomedical Literature Database (SinoMed), WanFang data and ClinicalTrials from inception to June 2019, with language restriction to English and Chinese. We included published RCTs and eligible clinical trials from ClinicalTrials.gov that compared NMBAs with placebo or usual treatment in adults with ARDS. We pooled data using random-effects models. The primary outcome was mortality. The secondary outcomes were the ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO2/FIO2), total positive end expiratory pressure (PEEP), plateau pressure (Pplat), days free of ventilator at day 28, barotrauma and ICU-acquired weakness.ResultsWe included 6 RCTs (n = 1557). Compared with placebo or usual treatment, NMBAs were associated with lower 21 to 28-day mortality (RR 0.72, 95% CI 0.53–0.97, I2 = 59%). NMBAs significantly improved oxygenation (Pao2:Fio2 ratios) at 48 hours (MD 27.26 mm Hg, 95% CI 1.67, 52.84, I2 = 92%) and reduced the incidence of barotrauma (RR 0.55, 95% CI 0.35, 0.85, I2 = 0). However, NMBAs had no effect on oxygenation (Pao2:Fio2 ratios) (MD 18.41 mm Hg, 95% CI -0.33, 37.14, I2 = 72%) at 24 hours. We also found NMBAs did not affect total PEEP, plateau pressure, days free of ventilation at day 28 and ICU-acquired weakness.ConclusionsIn patients with moderate-to-severe ARDS, the administration of NMBAs could reduce 21 to 28-day mortality and barotrauma, and improve oxygenation at 48 hours, but have no significant effects on 90-day/ICU mortality, days free of ventilation at day 28 and the risk of ICU-acquired weakness. Further large-scale, high-quality RCTs are needed to confirm our findings. Registration: PROSPERO (ID: CRD 42019139656).

Comparison of a novel clinical score to estimate the risk of REsidual neuromuscular block Prediction Score and the last train-of-four count documented in the electronic anaesthesia record: A retrospective cohort study of electronic data on file.

Residual neuromuscular block (rNMB) after surgery is not difficult to identify if proper neuromuscular monitoring is used, but many clinicians do not use quantitative neuromuscular monitoring. The aim of this study was to develop a REsidual neuromuscular block Prediction Score (REPS) to predict postoperative rNMB and compare the predictive accuracy of the prediction score with train-of-four count (TOFC) measurement at the end of a surgical case. Retrospective cohort study of data on file. Electronic patient data and peri-operative data on vital signs, administered medications, and train-of-four ratio (TOFR) obtained in the postoperative recovery rooms [postanaesthesia care unit (PACU)] at Massachusetts General Hospital in Boston, Massachusetts, USA. Quantitative TOFR measurements obtained on admission to the PACU were available from 2144 adult noncardiac surgical patients. Presence of rNMB at PACU admission, defined as a TOFR of less than 0.9. In the score development cohort (n=2144), rNMB occurred in 432 cases (20.2%). Ten independent predictors for residual paralysis were identified and used for the score development. The final model included: hepatic failure, neurological disease, high-neostigmine dose, metastatic tumour, female sex, short time between neuromuscular blocking agent administration and extubation, aminosteroidal neuromuscular blocking agent, BMI more than 35, absence of nurse anaesthetist and having an experienced surgeon. The model discrimination by C statistics was 0.63, 95% confidence interval (0.60 to 0.66), and risk categories derived from the REPS had a higher accuracy than the last documented intra-operative TOFC for predicting rNMB (net reclassification improvement score 0.26, standard error 0.03, P < 0.001). The REPS can be used to identify patients at greater risk of rNMB. This tool may inform anaesthetists better than an intra-operative TOFC and thus enable peri-operative anaesthetic practices to be tailored to the patient and minimise the undesirable effects of rNMB. Approved by Partners Human Research Committee (protocol number 2016P000940) at MGH in Boston, Massachusetts, USA on 25 April 2016.

Non-inferiority studies: is 'better' the enemy of 'good enough'?

Non-inferiority studies: is 'better' the enemy of 'good enough'?

Effects of neuromuscular blockers on transpulmonary pressures in moderate to severe acute respiratory distress syndrome.

To investigate whether neuromuscular blocking agents (NMBA) exert beneficial effects in acute respiratory distress syndrome (ARDS) by reason of their action on respiratory mechanics, particularly transpulmonary pressures (P L). A prospective randomised controlled study in patients with moderate to severe ARDS within 48h of the onset of ARDS. All patients were monitored by means of an oesophageal catheter and followed up for 48h. Moderate ARDS patients were randomised into two groups according to whether they were given a 48-h continuous infusion of cisatracurium besylate or not (control group). Severe ARDS patients did not undergo randomisation and all received cisatracurium besylate per protocol. The changes during the 48-h study period in oxygenation and in respiratory mechanics, including inspiratory and expiratory P L and driving pressure, were assessed and compared. Delta P L (∆P L) was defined as inspiratory P L minus expiratory P L. Thirty patients were included, 24 with moderate ARDS and 6 with severe ARDS. NMBA infusion was associated with an improvement in oxygenation in both moderate and severe ARDS, accompanied by a decrease in both plateau pressure and total positive end-expiratory pressure. The mean inspiratory and expiratory P L were higher in the moderate ARDS group receiving NMBA than in the control group. In contrast, there was no change in either driving pressure or ∆P L related to NMBA administration. NMBA could exert beneficial effects in patients with moderate ARDS, at least in part, by limiting expiratory efforts.

Clinical Practice Guidelines for Sustained Neuromuscular Blockade in the Adult Critically Ill Patient.

Clinical Practice Guidelines for Sustained Neuromuscular Blockade in the Adult Critically Ill Patient.

The Effect of Quantitative Neuromuscular Monitoring on the Incidence of Residual Neuromuscular Blockade and Clinical Outcomes

Neuromuscular blocking agents (NMBAs) are useful perioperative medications. Despite this utility, their administration is associated with increased morbidity due to residual neuromuscular blockade. Clinical testing prior to tracheal extubation is subjective, dependent on the patient’s cooperation, and not predictive of adequate respiratory function to prevent the occurrence of postoperative critical respiratory events. The use of peripheral nerve stimulators may improve detection of residual weakness; however, this technique does not reliably detect residual paralysis, as it requires the subjective (and imperfect) assessment of fade in response to train-of-four (TOF) stimulation. Quantitative neuromuscular monitoring can be accomplished through a variety of modalities and remains as the most effective and reproducible method of detecting residual paralysis after NMBA administration. In this review, we will discuss the various techniques that are used clinically to assess depth of block and adequacy of reversal, with a focus on quantitative (objective) neuromuscular monitoring.

Dose-dependent Association between Intermediate-acting Neuromuscular-blocking Agents and Postoperative Respiratory Complications.

Duration of action increases with repeated administration of neuromuscular-blocking agents, and intraoperative use of high doses of neuromuscular-blocking agent may affect respiratory safety. In a hospital-based registry study on 48,499 patients who received intermediate-acting neuromuscular-blocking agents, the authors tested the primary hypothesis that neuromuscular-blocking agents are dose dependently associated with the risk of postoperative respiratory complications. In the secondary analysis, the authors evaluated the association between neostigmine dose given for reversal of neuromuscular-blocking agents and respiratory complications. Post hoc, the authors evaluated the effects of appropriate neostigmine reversal (neostigmine ≤ 60 μg/kg after recovery of train-of-four count of 2) on respiratory complications. The authors controlled for patient-, anesthesia-, and surgical complexity-related risk factors. High doses of neuromuscular-blocking agents were associated with an increased risk of postoperative respiratory complications (n = 644) compared with low doses (n = 205) (odds ratio [OR], 1.28; 95% CI, 1.04 to 1.57). Neostigmine was associated with a dose-dependent increase in the risk of postoperative respiratory complications (OR, 1.51; 95% CI, 1.25 to 1.83). Post hoc analysis revealed that appropriate neostigmine reversal eliminated the dose-dependent association between neuromuscular-blocking agents and respiratory complications (for neuromuscular-blocking agent effects with appropriate reversal: OR, 0.98; 95% CI, 0.63 to 1.52). The use of neuromuscular-blocking agents was dose dependently associated with increased risk of postoperative respiratory complications. Neostigmine reversal was also associated with a dose-dependent increase in the risk of respiratory complications. However, the exploratory data analysis suggests that the proper use of neostigmine guided by neuromuscular transmission monitoring results can help eliminate postoperative respiratory complications associated with the use of neuromuscular-blocking agents.

Effect of administration of neuromuscular blocking agents in children with severe traumatic brain injury on acute complication rates and outcomes: a secondary analysis from a randomized, controlled trial of therapeutic hypothermia.

To evaluate the association between neuromuscular blocking agents and outcome, intracranial pressure, and medical complications in children with severe traumatic brain injury. A secondary analysis of a randomized, controlled trial of therapeutic hypothermia. Seventeen hospitals in the United States, Australia, and New Zealand. Children (< 18 yr) with severe traumatic brain injury. None for this secondary analysis. Children received neuromuscular blocking agent on the majority of days of the study (69.6%), and the modified Pediatric Intensity Level of Therapy scores (modified by removing neuromuscular blocking agent administration from the score) were increased on days when neuromuscular blocking agents were used (9.67 ± 0.21 vs 5.48 ± 0.26; p < 0.001). Children were stratified into groups based on exposure to neuromuscular blocking agents (group 1 received neuromuscular blocking agents each study day; group 2 did not). Group 1 had increased number of daily intracranial pressure readings more than 20 mm Hg (4.4 ± 1.1 vs 2.4 ± 0.5;p = 0.015) and longer ICU and hospital length of stay (p = 0.003 and 0.07, respectively, Kaplan-Meier). The Glasgow Outcome Score-Extended for Pediatrics at hospital discharge and 3, 6, and 12 months after traumatic brain injury and medical complications observed during the acute hospitalization were similar between groups. Administration of neuromuscular blocking agents was ubiquitous and daily administration of neuromuscular blocking agents was associated with intracranial hypertension but not outcomes-likely indicating that increased injury severity prompted their use. Despite this, neuromuscular blocking agent use was not associated with complications. A different study design-perhaps using randomization or methodologies-of a larger cohort will be required to determine if neuromuscular blocking agent use is helpful after severe traumatic brain injury in children.

Predictive value of allergy tests for neuromuscular blocking agents: tackling an unmet need.

Neuromuscular blocking agents (NMBAs) are a predominant cause of perioperative anaphylaxis in Europe. Diagnosis of NMBA allergy relies upon the careful review of the anaesthetic report complemented with skin tests. Additional diagnostic tests are quantification of specific IgE antibodies (sIgE) and basophil activation test (BAT). However, data on the predictive value of the skin tests, the BAT and the sIgE assays (drug-specific and substituted ammonium structures) are limited or not available, mainly because such exploration requires dangerous NMBA provocation tests. In this study, the predictive value of skin test, BAT and measurement of sIgE to substituted ammonium structures is gathered from a review of anaesthetic records of subsequent surgical procedures with NMBA administration and/or occurrence of perioperative incidents. We investigated a series of 272 patients with perioperative anaphylaxis, of whom 100 had undergone second general anaesthesia. Negative skin test and negative BAT assisted the selection of alternative NMBA, which were well tolerated in all cases. Five patients with a positive sIgE to rocuronium but with negative skin testing and BAT safely received rocuronium during second anaesthesia. Twelve patients with sIgE reactivity to morphine, but negative skin test and BAT to benzylisoquinolines, tolerated administration of cisatracurium or atracurium. Alternatively, benzylisoquinoline allergy went undetected in the morphine solid-phase assay. Skin test and BAT have an excellent negative predictive value in our series. The uneventful re-exposure of rocuronium in patients with an isolated positive sIgE result to rocuronium calls into question the predictive value of this assay and suggests sIgE serology to be less clinically predictive than the functional investigations relying upon activation of mast cells or basophils. The presence of a positive sIgE to substituted ammonium structures such as morphine does not preclude further use of benzylisoquinolines.