Adverse Respiratory Events in a Post-Anesthesia Care Unit

Improving Neuromuscular Monitoring Through Education-Based Interventions and Studying Its Association With Adverse Postoperative Outcomes: A Retrospective Observational Study

BACKGROUND

We assessed the association between education-based interventions, the frequency of train-of-four (TOF) monitoring, and postoperative outcomes.

METHODS

We studied adults undergoing noncardiac surgery from February 1, 2020 through October 31, 2021. Our education-based interventions consisted of 3 phases. An interrupted time-series analysis, adjusting for patient- and procedure-related characteristics and secular trends over time, was used to assess the associations between education-based interventions and the frequency of TOF monitoring, postoperative pulmonary complications (PPCs), 90-day mortality, and sugammadex dosage. For each outcome and intervention phase, we tested whether the intervention at that phase was associated with an immediate change in the outcome or its trend (weekly rate of change) over time. In a sensitivity analysis, the association between education-based interventions and postoperative outcomes was adjusted for TOF monitoring.

RESULTS

Of 19,422 cases, 11,636 (59.9%) had documented TOF monitoring. Monitoring frequency increased from 44.2% in the first week of preintervention stage to 83.4% in the final week of the postintervention phase. During the preintervention phase, the odds of TOF monitoring trended upward by 0.5% per week (odds ratio [OR], 1.005; 95% confidence interval [CI], 1.002-1.007). Phase 1 saw an immediate 54% increase (OR, 1.54; 95% CI, 1.33-1.79) in the odds, and the trend OR increased by 3% (OR, 1.03; 95% CI, 1.01-1.05) to 1.035, or 3.5% per week (joint Wald test, P < .001). Phase 2 was associated with a further immediate 29% increase (OR, 1.29; 95% CI, 1.02-1.64) but no significant association with trend (OR, 0.96; 95% CI, 0.93-1.01) of TOF monitoring (joint test, P = .04). Phase 3 and postintervention phase were not significantly associated with the frequency of TOF monitoring (joint test, P = .16 and P = .61). The study phases were not significantly associated with PPCs or sugammadex administration. The trend OR for 90-day mortality was larger by 24% (OR, 1.24; 95% CI, 1.06-1.45; joint test, P = .03) in phase 2 versus phase 1, from a weekly decrease of 8% to a weekly increase of 14%. However, this trend reversed again at the transition from phase 3 to the postintervention phase (OR, 0.82; 95% CI, 0.68-0.99; joint test, P = .05), from a 14% weekly increase to a 6.2% weekly decrease in the odds of 90-day mortality. In sensitivity analyses, adjusting for TOF monitoring, we found similar associations between study initiatives and postoperative outcomes. TOF monitoring was associated with lower odds of PPCs (OR, 0.69; 95% CI, 0.55-0.86) and 90-day mortality (OR, 0.79; 95% CI, 0.63-0.98), but not sugammadex dosing (mean difference, -0.02; 95% CI, -0.04 to 0.01).

CONCLUSIONS

Our education-based interventions were associated with both TOF utilization and 90-day mortality but were not associated with either the odds of PPCs or sugammadex dosing. TOF monitoring was associated with reduced odds of PPCs and 90-day mortality.

Coadministration of intravenous calcium along with neostigmine for rapid neuromuscular blockade recovery: A systematic review and meta-analysis

Postoperative residual curarization (PORC) and the impact of the coadministration of intravenous calcium along with an acetylcholinesterase inhibitor on it are not well addressed. Extensive electronic database screening was done until October 7, 2022 after enlisting the protocol of this systematic review in PROSPERO (CRD42021274879). Randomized controlled trials (RCTs) evaluating the impact of intravenous calcium and neostigmine coadministration on neuromuscular recovery were included in this meta-analysis. Our search retrieved four RCTs with a total of 266 patients. The application of calcium shortened the neuromuscular recovery time (SMD = -2.13, 95% confidence interval [CI]: -2.66 to -1.59, I2 = 66%) and reduced the risk of PORC at 5 min (odds ratio [OR] = 0.21, 95% CI: 0.10-0.46, I2 = 0%), with an improved train-of-four (TOF) ratio at 5 min (mean difference [MD] = 9.28, 95% CI: 4-14.57, I2 = 66%). However, neither significant reduction in PORC at 10 min (OR = 0.41, 95% CI: 0.15-1.09, I2 = 0%) nor a better TOF ratio was associated with coadministration of calcium (MD = 0.40, 95% CI: -1.3-2.11). Coadministration of calcium along with neostigmine during the early period of neuromuscular blockade reversal can be used to enhance neuromuscular recovery.

Incidence and factors associated with post-anesthesia care unit complications in resource-limited settings: An observational study

Background and aims

Postoperative complications are frequent encounters in the patients admitted to postanesthesia care units (PACU). The main aim of this study was to assess the incidence of complications and associated factors among surgical patients admitted in limited-resource settings of the PACU.

Methods

This is an observational study of 396 surgical patients admitted to PACU. This study was conducted from February 1 to March 30, 2021, in Ethiopia. Study participants' demographics, anesthesia, and surgery-related parameters, PACU complications, and length of stay in PACU were documented. Multivariate and bivariate logistic regression analyses, the odds ratio (OR), and 95% confidence interval (CI) were calculated. p-value < 0.05 was considered as statistically significant.

Results

The incidence of complications among surgical patients admitted to PACU was 54.8%. Of these, respiratory-related complications and postoperative nausea/vomiting were the most common types of PACU complications. Being a female (adjusted odds ratio [AOR] = 2.928; 95% CI: 1.899-4.512) was significantly associated with an increased risk of developing PACU complications. Duration of anesthesia >4 h (AOR = 5.406; 95% CI: 2.418-12.088) revealed an increased risk of association with PACU complications. The occurrences of intraoperative complications (AOR = 2.238; 95% CI: 0.991-5.056) during surgery were also associated with PACU complications. Patients who develop PACU complications were strongly associated with length of PACU stay for >4 h (AOR = 2.177; 95% CI: 0.741-6.401).

Conclusion

The identified risk factors for complications in surgical patients admitted to PACU are female sex, longer duration of anesthesia, and intraoperative complications occurrences. Patients who developed complications had a long time of stay in PACU. Based on our findings, we recommend the PACU team needs to develop area-specific institutional guidelines and protocols to improve the patients' quality of care and outcomes in PACU.

The association between residual neuromuscular blockade (RNMB) and critical respiratory events: a prospective cohort study

Background

Inadequate neuromuscular recovery might impair pulmonary function among adult patients who undergo general anaesthesia and might thus contribute to critical respiratory events in the post-anaesthesia care unit (PACU). The pilot study aims to understand the baseline incidence of residual neuromuscular blockade (RNMB) and postoperative critical respiratory events (CREs), which are described in a modified Murphy’s criteria in the PACU.

Method

This is a prospective cohort study from January to March 2017 from a tertiary hospital in Saudi Arabia with thirty adult patients over 18 years old scheduled for elective surgery under general anaesthesia with neuromuscular blocking drugs (NMBDs) who were enrolled in the study. The Mann-Whitney U tests, chi-square tests and independent-samples T tests were used. The train-of-four (TOF) ratios were measured upon arrival in the PACU by using acceleromyography with TOF-Scan. Subjects’ demographics, perioperative data and the occurrence of postoperative CREs in the PACU were recorded.

Results

Twenty-six (86.7%) patients out of thirty in the study have received rocuronium as NMBDs whilst neostigmine as a reversal drug with only 23 (76.7%). The incidence of RNMB (TOF ratio < 0.9) was in 16 patients (53.3%). The incidence of RNMB was significantly higher in female patients (p = 0.033), in patients who had not undergone quantitative neuromuscular monitoring before extubation (p = 0.046) and in patients with a shorter duration of surgery (p = 0.001). Postoperative CREs occurred in twenty patients (66.7%), and there were significantly more of these CREs among patients with RNMB (p = 0.001). In addition, a statistically significant difference was observed in the occurrence of CREs according to body mass index (p = 0.047).

Conclusion

This research showed that RNMB is a significant contributing factor to the development of critical respiratory events during PACU stay. Therefore, routine quantitative neuromuscular monitoring is recommended to reduce the incidence of RNMB.

Comparison of the TetraGraph and TOFscan for monitoring recovery from neuromuscular blockade in the Post Anesthesia Care Unit

STUDY OBJECTIVE

Comparison of the TetraGraph (TG) and TOFscan (TS) for monitoring recovery from neuromuscular blockade in the Post Anesthesia Care Unit (PACU).

DESIGN

Randomized, multicenter trial.

SETTING

PACU in three tertiary care hospitals.

PATIENTS

120 patients (40 per site) receiving neuromuscular blockade during elective surgery.

INTERVENTIONS

Patients were enrolled preoperatively and intraoperative neuromuscular blockade management was at the discretion of the anesthesiologist. Upon arrival to the PACU, patients were randomized to have either TG or TS placed on their dominant hand. The alternate device (TS or TG) was placed on the non-dominant hand. Following simultaneous ulnar nerve stimulation on each arm, the response of the adductor pollicis was measured.

MEASUREMENTS

Train-of-four ratios (TOFRs) were obtained upon arrival to the PACU (t = 0), after 5 min (t = + 5) and after +10 min (t = + 10).

MAIN RESULTS

There was there was no significant difference in the mean TOFRs obtained with the TG and TS at t = 0 (0.97 ± 0.18 vs 0.94 ± 0.13, P = 0.06, respectively) and t = + 5 (0.96 ± 0.20 vs 0.95 ± 0.12, P = 0.29, respectively). At (t = + 10), there was a statistically significant difference in mean TOFRs obtained with the TG and TS, (0.99 ± 0.14 vs 0.94 ± 0.12, P < 0.001, respectively). The bias between devices at t = 0 was estimated to be 0.03 (95% CI, -0.29 to 0.35, P = 0.26); at t = + 5 min, it was estimated to be 0.02 (95% CI, -0.36 to 0.40, P = 0.54); and at t = +10 min, it was estimated to be 0.05 (95% CI, -0.25 to 0.36, P = 0.77).

CONCLUSIONS

TS and TG provide interchangeable quantitative measurements once the TOF ratio has returned to a value of 0.90 or greater in the PACU.

Epidemiology and outcomes of residual neuromuscular blockade: A systematic review of observational studies

OBJECTIVES

Complete reversal of neuromuscular blockade (NMB) is important for patient safety and prognosis following surgical procedures involving NMB agents (NMBAs). Published evidence on the epidemiology and consequences of residual neuromuscular blockade (rNMB; incomplete neuromuscular recovery) in real-world clinical settings is lacking with advances in NMB management. Therefore, we aimed to examine the burden of rNMB and its associated clinical, economic and humanistic outcomes using a systematic review framework.

REVIEW METHODS

Electronic and conference database searches were performed to include observational studies examining rNMB or related outcomes in adults undergoing surgery and receiving NMBAs with or without NMBA antagonists.

RESULTS

Of 1438 screened abstracts, 58 studies with 25,277 total patients were included. Inconsistent definitions of rNMB were reported across studies with 44 (76%) and 29 (50%) studies utilizing quantitative and qualitative measures to detect rNMB, respectively. The most common definition of rNMB was train-of-four ratio (TOFR) <0.9 (29 studies) and TOFR <0.7 (16 studies) measured at post-anesthesia care unit (PACU) entry. For TOFR <0.9 at PACU entry, rNMB incidence ranged from 0% to 90.5% (median 30%) overall; 0% to 16.0% in the sugammadex (SUG) group; 3.5% to 90.5% in the neostigmine (NEO) group; and 15% to 89% in the spontaneous recovery (SR) group. Twenty-one studies reported clinical outcomes (reintubation, mild hypoxemia, or a respiratory event) or resource utilization outcomes (hospital/PACU length of stay [LOS]) by presence/absence of rNMB. Patients with rNMB had higher rates of acute respiratory events compared to those without rNMB.

CONCLUSIONS

Real-world observational studies show a significant burden of rNMB and associated health sequelae, though rNMB measures were not reported consistently across studies. Appropriate quantitative measurement is needed to accurately identify rNMB, and interventions are needed to reduce its burden and associated adverse outcomes.

Incidence of residual neuromuscular blockade and use of neuromuscular blocking agents with or without antagonists: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

Neuromuscular blocking agents (NMBAs) have revolutionized the field of anesthesiology as they facilitate airway management and ensure optimal surgical conditions. Despite their beneficial and ubiquitous use during surgery, delayed or partial recovery from NMBAs, referred to as residual neuromuscular block (rNMB), is a common clinical problem. While it is well accepted that the antagonist sugammadex, compared to neostigmine, can more rapidly reverse rocuronium-induced NMB regardless of depth of block, the occurrence of rNMB for routinely used combinations of NMBAs with sugammadex or neostigmine has not yet been quantified or evaluated systematically.

REVIEW METHODS

We conducted a systematic literature review and meta-analysis of randomized controlled trials (RCTs) to quantify and compare the incidence of rNMB [defined as train-of-four ratio (TOFR) <0.9] in patients with moderate and deep neuromuscular block. Methods recommended by Cochrane Collaboration and PRISMA group were followed.

RESULTS

A total of 35 RCTs were identified, of which 20 contributed to the meta-analysis. For moderate block, rNMB incidence at 2 min after sugammadex administration was 19.2% (95% CI 0.0-57.8; 122 patients) and declined to 2.8% (95% CI 0.0-16.7; 93 patients) at 6 min post administration. For timepoints 10 to 60 min after administration, rNMB incidence ranged between 0.05% to 2.8%. In contrast, rNMB incidence at 2 min after neostigmine administration was 100% (95% CI 89.9-100; 182 patients) and was 82% (95% CI 71.4-91.2; 93 patients) at 6 min post administration. For timepoints 10 to 60 min after administration, rNMB incidence ranged between 14 and 32%. For deep block, rNMB incidence following sugammadex was essentially reduced to 1% at 15 min after administration. Residual NMB incidence following neostigmine remained at or above 95% for the first 60 min after administration.

CONCLUSIONS

Overall, based on evidence from 20 RCTs, our results suggest that the combination of rocuronium or vecuronium plus sugammadex is more effective and more rapid in reversing NMB compared with combinations of rocuronium, vecuronium, cisatracurium, or pancuronium plus neostigmine.

Evaluation of a Safety Protocol for the Management of Thirst in the Postoperative Period

PURPOSE

To associate medications, anesthetic techniques, and clinical conditions that interfere in the time of patient approval in the safety protocol for thirst management.

DESIGN

A quantitative, analytical, and longitudinal study conducted in Southern Brazil.

METHODS

A nonprobabilistic sample, of 203 adult patients in the immediate postoperative period, evaluated every 15 minutes for 1 hour.

FINDINGS

A general prevalence of thirst of 67.7%, and mean intensity of 6.38. Fentanyl, morphine, rocuronium, and sevoflurane increased lack of approval in the protocol within 30 minutes (P < .05). General anesthesia (P < .0001) and level of consciousness (95.4%) presented the highest nonapproval rates.

CONCLUSIONS

Anesthetics and general anesthesia delayed protocol approval; however, after 30 minutes, 75.4% of patients had been approved. Level of consciousness was the main criterion of disapproval. The protocol identified crucial clinical conditions that made it impossible for the patient to receive thirst relief strategies and demonstrated that thirst can be satiated precociously with safety.

Severity of disease scoring systems and mortality after non-cardiac surgery

Background

Mortality after surgery is frequent and severity of disease scoring systems are used for prediction. Our aim was to evaluate predictors for mortality after non-cardiac surgery.

Methods

Adult patients admitted at our surgical intensive care unit between January 2006 and July 2013 was included. Univariate analysis was carried using Mann–Whitney, Chi-square or Fisher's exact test. Logistic regression was performed to assess independent factors with calculation of odds ratio and 95% confidence interval (95% CI).

Results

4398 patients were included. Mortality was 1.4% in surgical intensive care unit and 7.4% during hospital stay. Independent predictors of mortality in surgical intensive care unit were APACHE II (OR = 1.24); emergent surgery (OR = 4.10), serum sodium (OR = 1.06) and FiO₂ at admission (OR = 14.31). Serum bicarbonate at admission (OR = 0.89) was considered a protective factor. Independent predictors of hospital mortality were age (OR = 1.02), APACHE II (OR = 1.09), emergency surgery (OR = 1.82), high-risk surgery (OR = 1.61), FiO₂ at admission (OR = 1.02), postoperative acute renal failure (OR = 1.96), heart rate (OR = 1.01) and serum sodium (OR = 1.04). Dying patients had higher scores in severity of disease scoring systems and longer surgical intensive care unit stay.

Conclusion

Some factors influenced both surgical intensive care unit and hospital mortality.

[Severity of disease scoring systems and mortality after non-cardiac surgery]

BACKGROUND

Mortality after surgery is frequent and severity of disease scoring systems are used for prediction. Our aim was to evaluate predictors for mortality after non-cardiac surgery.

METHODS

Adult patients admitted at our surgical intensive care unit between January 2006 and July 2013 was included. Univariate analysis was carried using Mann-Whitney, Chi-square or Fisher's exact test. Logistic regression was performed to assess independent factors with calculation of odds ratio and 95% confidence interval (95% CI).

RESULTS

4398 patients were included. Mortality was 1.4% in surgical intensive care unit and 7.4% during hospital stay. Independent predictors of mortality in surgical intensive care unit were APACHE II (OR=1.24); emergent surgery (OR=4.10), serum sodium (OR=1.06) and FiO₂ at admission (OR=14.31). Serum bicarbonate at admission (OR=0.89) was considered a protective factor. Independent predictors of hospital mortality were age (OR=1.02), APACHE II (OR=1.09), emergency surgery (OR=1.82), high-risk surgery (OR=1.61), FiO₂ at admission (OR=1.02), postoperative acute renal failure (OR=1.96), heart rate (OR=1.01) and serum sodium (OR=1.04). Dying patients had higher scores in severity of disease scoring systems and longer surgical intensive care unit stay.

CONCLUSION

Some factors influenced both surgical intensive care unit and hospital mortality.

Current Status of Neuromuscular Reversal and Monitoring

Postoperative residual neuromuscular block has been recognized as a potential problem for decades, and it remains so today. Traditional pharmacologic antagonists (anticholinesterases) are ineffective in reversing profound and deep levels of neuromuscular block; at the opposite end of the recovery curve close to full recovery, anticholinesterases may induce paradoxical muscle weakness. The new selective relaxant-binding agent sugammadex can reverse any depth of block from aminosteroid (but not benzylisoquinolinium) relaxants; however, the effective dose to be administered should be chosen based on objective monitoring of the depth of neuromuscular block.

To guide appropriate perioperative management, neuromuscular function assessment with a peripheral nerve stimulator is mandatory. Although in many settings, subjective (visual and tactile) evaluation of muscle responses is used, such evaluation has had limited success in preventing the occurrence of residual paralysis. Clinical evaluations of return of muscle strength (head lift and grip strength) or respiratory parameters (tidal volume and vital capacity) are equally insensitive at detecting neuromuscular weakness. Objective measurement (a train-of-four ratio greater than 0.90) is the only method to determine appropriate timing of tracheal extubation and ensure normal muscle function and patient safety.