Laryngospasm: review of different prevention and treatment modalities

A Complex Case of Laryngospasm Secondary to COVID-19 Infection in a 40-Year-Old Male

COVID-19 is a novel viral infection with a wide variety of clinical manifestations ranging from asymptomatic cases to severe respiratory illness. Laryngospasm is a spontaneous sustained closure of the laryngeal muscles leading to acute airway obstruction. We report a case of a 40-year-old male with a history of nephrolithiasis who underwent laparoscopic pyeloplasty and developed laryngospasm as a consequence of contracting COVID-19. The case was further complicated by the development of pneumothorax and pleural effusion during the postoperative period. The patient was managed with supplemental oxygen, antibiotics, antiviral therapy, and close monitoring. He recovered without any additional complications. This case highlights the potential initial clinical manifestation and the importance of early diagnosis and treatment of COVID-19 infection in surgical patients.

The efficacy of magnesium sulphate in preventing laryngospasm in paediatric patients undergoing general anaesthesia: A systematic review and meta-analysis of randomised control trials

BACKGROUND

Laryngospasm is sustained closure of the airways and can be a life-threatening condition. Magnesium sulphate is postulated to reduce the incidence of laryngospasm if administered peri-operatively. This systematic review and meta-analysis was performed to assess the efficacy of magnesium sulphate in preventing peri-operative laryngospasm in paediatric patients undergoing non-cardiac surgery.

METHODS

Four databases and a trial registry were searched. Inclusion criteria were paediatric patients undergoing general anaesthesia. Exclusion criteria were patients who underwent cardiopulmonary bypass during surgery. The intervention of interest was the peri-operative administration of magnesium sulphate. The intervention was compared to either a placebo or other pharmacological agent. The primary outcome was the incidence of laryngospasm. A meta-analysis of all studies was performed. Sub-group analysis was subsequently performed.

RESULTS

A total of 953 patients from 13 trials were included in this study. Nine RCTs administered magnesium intravenously and 4 RCTs administered magnesium locally. Laryngospasm rates were 6% lower in the magnesium group (OR 0.48 [95% CI 0.25-0.96], p = 0.04) compared to control in the pooled data. Subgroup analysis showed laryngospasm rates were lower by 12.5% (Odds Ratio 0.26 [CI 0.09-0.76], p = 0.01) in the local magnesium group. Subgroup analysis of studies that only administered intravenous magnesium did not show a statistically significant difference in the incidence of laryngospasm (OR 0.73 [95% CI 0.33-1.63], p = 0.44).

CONCLUSIONS

This review shows a potential role for magnesium in the prevention of laryngospasm in paediatric patients undergoing general anaesthesia. There is a correlation between local administration of magnesium and reduction in laryngospasm rates. Further studies are required to assess the efficacy of intravenous magnesium in prevention of laryngospasm.

REGISTRATION

Prospective Register of Systematic Reviews (PROSPERO); PROSPERO ID CRD42022307868 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022307868).

Remimazolam: a randomized controlled study of its suitability for insertion of a supraglottic airway

PURPOSE

Loss of motor response to thrusting the jaw forward is a useful indicator for uncomplicated insertion of a supraglottic airway. The aim of this study was to assess the suitability of remimazolam for insertion of a supraglottic airway assessed by loss of response to jaw thrusting.

METHODS

Seventy patients, who were scheduled for elective surgeries under general anesthesia, were allocated randomly to one of two groups. In one group (remimazolam group), remimazolam was infused 12 mg kg-1 h-1 (50 mg maximum), and in the other (propofol group), propofol was infused at 120 mg kg-1 h-1 (500 mg maximum). Once the eyelash reflex disappeared, response to jaw thrusting was assessed. Primary outcome measure was the proportion of patients with loss of response to jaw thrusting before reaching the maximum dose of the test drug. We planned an interim analysis (of one time) after 40 patients, using the Pocock adjustment method.

RESULTS

From the interim analysis results, the study was stopped after recruitment of 40 patients. Loss of response to jaw thrusting was observed in all of 21 patients (100%) in the propofol group, and in 9 of 19 patients (47%) in the remimazolam group. There was a significant difference in the proportion between the groups (P = 0.0001, 95% CI for difference 30-75%).

CONCLUSION

Remimazolam frequently does not inhibit response to jaw thrusting, and thus remimazolam is not a suitable induction agent for uncomplicated insertion of a supraglottic airway unless either a neuromuscular blocking agent or an opioid is co-administered.

Dynamic vocal cord behavior and stridor during emergence from general anesthesia in small children with supraglottic airway

PURPOSE

Stridor during emergence from anesthesia is not rare in children managed with supraglottic airway (SGA). However, we know little about the mechanisms of stridor and behavior of the vocal cords (VC). This study aimed to clarify patterns of VC movement and laryngeal airway maintenance function during recovery from anesthesia in children with SGA.

METHODS

This is a secondary analysis of data collected from an observational study involving 27 anesthetized children. Using a multi-panel recording system, endoscopic VC image, vital sign monitor, multi-channel tracings of respiratory variables and respiratory sound and patient's view were simultaneously captured in one monitor. Inspiratory and expiratory VC angles formed by lines connecting anterior and posterior commissures were measured at the first spontaneous breath and the breath one minute after the first breath. VC narrowing and dilation were assessed by differences of VC angles.

RESULTS

Inspiratory VC narrowing (median (IQR): 5.3 (2.7, 9.1) degree at the first breath) and dilation (- 2.7 (- 3.8, - 1.7) degree at the first breath) were observed in 15 and 12 out of 27 children, respectively. The former group achieved greater tidal volume compared to the latter in one minute. Five children (19%) temporarily developed stridor-like sound from outside with inspiratory VC narrowing. The stridor-like sound was captured by microphones attached to the neck and anesthesia circuit, but was not evident from the chest.

CONCLUSION

Laryngeal narrowing occurs in half of the children with SGA during emergence from anesthesia, and temporal stridor-like sound is relatively common.

CLINICAL TRIAL REGISTRATION

UMIN (University Hospital Information Network) Clinical Registry: UMIN000025058 ( https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000028697 ).

Positional Change Used to Manage Postextubation Respiratory Failure in a Child With Cerebral Palsy

Dental treatment for patients with cerebral palsy (CP) is often performed under general anesthesia due to involuntary movements that can render dental treatment difficult. Since CP is often accompanied by spasticity, care must be taken when positioning patients during general anesthesia. We report the management of a 14-year-old girl with CP and epilepsy undergoing general anesthesia for dental treatment who experienced respiratory failure due to acute thoracoabdominal muscle hypertonia after extubation. She had a history of cardiac arrest due to respiratory failure caused by acute muscle hypertonia and successful resuscitation. General anesthesia was induced after careful positioning of the patient to prevent spastic muscle stretching, and the dental treatment was completed without complications. However, upon awakening after extubation, the patient developed respiratory failure due to acute muscle hypertonia. The patient was resedated and repositioned from a supine to a sitting position, and her symptoms improved. There was no recurrence of muscle hypertonia, and she recovered fully without complications. In this case, respiratory failure associated with acute muscle hypertonia was successfully managed by position change after initial treatment with positive-pressure ventilation and propofol. It is important to be prepared for the possibility of respiratory failure associated with acute muscle hypertonia and its countermeasures when providing general anesthesia for patients with CP.

Comparison of modified anterior and traditional posterior accesses for ultrasound-guided superior laryngeal nerve block in awake endotracheal intubation: study protocol for a randomised non-inferiority clinical trial

INTRODUCTION

Awake tracheal intubation (ATI) involves placing a tracheal tube in an awake, spontaneously breathing patient. Superior laryngeal nerve block (SLNB) can effectively abolish the glottic closure reflex, and blunt the sensation of the structures above the cords. A method that consists of SLNB along with translaryngeal injection (TLI) can provide satisfactory anaesthesia and intubating conditions. We present a novel modified access of SLNB, ultrasound (US)-guided anterior SLNB, to aid awake videolaryngoscopes-assisted endotracheal intubation in adult elective surgery patients, and we compare the effectiveness and safety to traditional US-guided posterior SLNB.

METHODS AND ANALYSIS

A total of 100 adult elective surgery patients requiring general endotracheal anaesthesia will be randomly assigned to the modified group (modified US-guided anterior SLNB) or the traditional group (traditional US-guided posterior SLNB). After SLNB, all participants will be performed with TLI. The primary outcome is the proportion of acceptable intubation conditions based on intubation scores. Secondary outcomes include: (a) the first-attempt intubation success rate, (b) haemodynamic changes during ATI, (c) time taken for airway anaesthesia and intubation, (d) recall of intubation, (e) participant perception of comfort during intubation, (f) perioperative complication rate. This report describes the study design of this randomised controlled trial.

ETHICS AND DISSEMINATION

The study protocol has been approved by an ethical committee of the West China Hospital (Sichuan University), and registered at the Chinese Clinical Trials Register (www.chictr.org.cn). Results will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ChiCTR2200058086.

[Airway Management in Paediatric Anaesthesia]

Due to their low reserves, hypoxia and cardiac arrest occur rapidly in children. The continuous securing of the airway as well as maintenance of oxygenation and ventilation are of prior importance in paediatric anaesthesia. For this purpose, bag-mask ventilation and the opening of the upper airway must be trained and mastered in particular. As the most important supraglottic device, the laryngeal mask has been evaluated for patients of all ages.

The Nature, Frequency, and Timing of Pediatric Sedation Adverse Events

OBJECTIVES

The nature and frequency of pediatric sedation adverse events (AEs) have been well described. However, the timing of specific AEs in induction, procedure, and recovery phase of sedation remains unknown. The objective was to describe the nature, frequency, and timing of AEs. We hypothesized that most AEs would start at the induction phase.

METHODS

We examined prospectively collected data of sedation encounters of children 3 months to 18 years of age, characterized by at least 1 AE, from January 1, 2013 to December 31, 2020. Patient characteristics, primary diagnosis, procedure type, nature, frequency, and timing of AEs were reported.

RESULTS

Of 12 012 sedation encounters, the mean age was 7.6 (SD = 4.9) years, most (89%) were American Society of Anesthesiologists II risk, the most common diagnosis was hematology/oncology (27.3%) and the most common procedure radiologic (47.8%). At least 1 AE occurred during 765 (6.4%) encounters. Respiratory AEs were most common (n = 645, 5.4% of all encounters) and started more often during induction (64.5% of respiratory AEs). Partial upper airway obstruction was the most common respiratory AE (2.8% of all encounters). Partial (59.4%) and complete (77.3%) upper airway obstruction and apnea (84%) all began more often during induction. Laryngospasm (48.4% vs 46.8%) and hypoxemia (59.3% vs 39%) were similarly distributed between induction and procedure, respectively, though they were rare during recovery.

CONCLUSIONS

Most respiratory events in this cohort started during the induction or procedure phases. The sedation team should be especially prepared to administer rescue maneuvers and allocate staff/resources during these phases.

Anticholinergics and serious adverse events in pediatric procedural sedation: A report of the pediatric sedation research consortiums

BACKGROUND

Pediatric sedation is a clinical activity with potential for serious but rare airway adverse events, particularly laryngospasm. Anticholinergic drugs, atropine and glycopyrrolate, are frequently used with the intention to improve sedation safety by virtue of their antisialagogue effects.

AIMS

The objective of this study is to describe the current practice of anticholinergic use in pediatric sedation and to compare the frequency of serious sedation-related adverse events in patients who received anticholinergics to those who did not.

METHODS

We examined prospectively collected data from the Pediatric Sedation Research Consortium database. Patient characteristics, procedure type, sedation provider, sedatives, location of sedation, anticholinergic administered, adverse events, and airway interventions were reported. Propensity score matching and multivariable logistic regression were used to test whether any association exists between anticholinergic use and serious sedation-related adverse events.

RESULTS

Anticholinergics were administered in 7.1% (n = 18 707) of all cases (n = 263 883) reported between November 2011 and October 2017. When anticholinergics were used, atropine was used in 22% (n = 4111) and glycopyrrolate in 78.1% (n = 14 601) of sedations. Use of anticholinergics was more common in patients with well-described risk factors for airway adverse events: active/history of upper respiratory infection, history of reactive airway disease/asthma, and exposure to smoke. However, infants and ASA 3 patients were not associated with higher rate of anticholinergic use. Anticholinergic use was independently associated with an increase in the odds of serious adverse events, OR 1.8 (95% CI 1.6-2.1), especially airway adverse events.

CONCLUSIONS

In this large Pediatric Sedation Research Consortium study, we found the use of anticholinergic adjuvants independently associated with greater odds of serious adverse events, especially airway adverse events, after adjusting for well-known sedation risk factors using propensity score matching and multivariate analysis.

Comparison of the effects of intravenous propofol and propofol with low-dose ketamine on preventing postextubation cough and laryngospasm among patients awakening from general anaesthesia: A prospective randomised clinical trial

BACKGROUND

Coughing and laryngospasm are undesirable consequences occurring when patients awaken from general anaesthesia. The objective of the study aimed to compare the effects of intravenous propofol and propofol with low-dose ketamine on preventing postextubation cough and laryngospasm.

METHODS

In all, 120 patients scheduled surgery under general anaesthesia were randomly assigned into three groups. Patients in the control group (C-group) received intravenous 0.9% NaCl, while patients in the propofol group (P-group) received intravenous 0.25mg/kg propofol and patients in the propofol combined with ketamine group (PK-group) received intravenous 0.25mg/kg of propofol plus 0.15mg/kg of ketamine. Drugs were administered before extubation. Incidence and severity of coughing and laryngospasm were recorded by a blinded anaesthesiologist.

RESULTS

Subjects of the PK-group (25%) experienced significantly reduced incidence of postoperative cough than that in the P-group (55%) and C-group (72.5%) (all P < 0.05). The severity of cough in the PK-group was significantly less than that in the P-group and C-group (P = 0.039 and P < 0.001, respectively). No significant difference was found in the incidence and severity of laryngospasm between comparison groups.

CONCLUSION

Intravenous combination of propofol and low-dose ketamine significantly reduced the incidence and severity among patients awakening from general anaesthesia.

The use of laryngeal mask airway for tonsillectomy and adenoidectomy

PURPOSE

Patients undergoing tonsillectomy and adenoidectomy traditionally receive anesthesia with endotracheal intubation (ETT) for airway management. The laryngeal mask airway (LMA) may be used instead and may be associated with less airway stimulation and shorter operating room times. The purpose of this study was to report on a large cohort of patients undergoing tonsillectomy and/or adenoidectomy while using the LMA for airway maintenance during anesthesia.

METHODS

Patients undergoing tonsillectomy and adenoidectomy between January 6, 2017 and January 6, 2020 with a LMA were reviewed for safety outcomes. We compared two cohorts of patients with LMA and ETT to analyze the effect on operating room times.

RESULTS

Our study identified 1042 patients who met criteria for review. The incidence of cases requiring conversion to ETT (1.2%) and laryngospasm (0.3%) in our cohort is lower than previously suggested by the literature. The patients who underwent surgery with the LMA spent less time in the operating room (p = 0.004) compared to the ETT group.

CONCLUSION

The use of the LMA may be a safe and effective option for airway management during tonsillectomy and adenoidectomy. There may be a benefit of OR time reduction in patients undergoing anesthesia with an LMA compared to ETT.

Comparison of the Effects of Desflurane, Sevoflurane, and Propofol on the Glottic Opening Area during Remifentanil-Based General Anesthesia Using a Supraglottic Airway Device

Purpose

The aim of this study was to compare the effects of desflurane, sevoflurane, and propofol on the glottic opening area during general anesthesia using remifentanil.

Methods

Ninety patients undergoing hand and upper limb surgery combined with brachial plexus block under general anesthesia were enrolled in the study. The patients were randomized into three groups to receive desflurane (group D), sevoflurane (group S), or propofol (group P) for maintenance of anesthesia. Following induction of general anesthesia with remifentanil, continuous fiberoptic video recording around the glottis via an i-gel™ supraglottic device was started after establishing mechanical ventilation. Desflurane, sevoflurane, or propofol was administrated after video recording was started. The changes in normalized glottic opening area (n-GOA) and peak inspiratory pressure (PIP) during surgery were compared between the three groups.

Results

Intraoperative changes of n-GOA in group D showed significant differences compared with group S and group P (−0.0656 ± 0.0772 vs. −0.0076 ± 0.0499 and +0.0269 ± 0.0809, P=0.005 and P < 0.0001). The changes of PIP in group D showed significant differences compared with group S and group P (+3.7 ± 3.4 cmH₂O vs. +1.0 ± 1.3 cmH₂O and −0.3 ± 3.6 cmH₂O, P=0.002 and P < 0.0001). Four cases of relapsed glottic stenosis in group D were improved by changing desflurane to propofol.

Conclusions

Desflurane narrowed the n-GOA and increased the PIP compared to sevoflurane and propofol during general anesthesia with remifentanil. Clinicians should be aware of the possibility of glottic stenosis during desflurane-remifentanil anesthesia when the airway is secured by a supraglottic airway device without the use of neuromuscular blockade.

Out-of-hospital ketamine: review of a growing trend in patient care

Ketamine is a unique medication with a long history of use in the emergency department. Out-of-hospital indications for ketamine have been explored and are currently expanding in some systems. This article provides background on ketamine history and pharmacology, its use in the hospital environment and possible applications for emergency medical services usage of this medication. Contraindications and adverse reactions are discussed to provide education on the nuances of ketamine administration and mitigation strategies. Out-of-hospital indications for ketamine are discussed including airway management, rapid sequence induction, analgesia, sedation, and treatment of excited delirium.

Management of Refractory Laryngospasm

Laryngospasm has been well described in patients emerging from general anesthesia (GA) and is routinely managed with intermittent positive-pressure mask ventilation, a temporary increase in the depth of anesthesia, or small, titrated amounts of succinylcholine. Patients with severe laryngospasm require reintubation to maintain adequate oxygenation and ventilation. However, reintubation may be only a temporary solution because laryngospasm may recur during re-emergence and re-extubation; thus, anesthesiologists need a comprehensive plan that addresses potential causes of laryngospasm and incorporates continuous positive airway pressure (CPAP) for patients with difficulty emerging from GA. Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) is a noninvasive ventilation and oxygenation technique used to provide apneic oxygenation, which also generates CPAP. THRIVE uses a high-flow nasal cannula and is more easily tolerated than CPAP with a tight-fitting mask. To our knowledge, we present the first case of refractory laryngospasm during emergence from GA that was successfully managed with THRIVE.

Incidence and Associated Factors of Laryngospasm among Pediatric Patients Who Underwent Surgery under General Anesthesia, in University of Gondar Compressive Specialized Hospital, Northwest Ethiopia, 2019: A Cross-Sectional Study

Introduction

Laryngospasm is a glottis closure due to reflex constriction of the laryngeal muscles. It can occur at any phase of the anesthetic. Different studies have been done previously with various results and indicative values which initiated us to do this research. This study aimed to assess the incidence and associated factors of laryngospasm among pediatric patients who underwent surgery under general anesthesia (GA).

Methods

Institution-based, cross-sectional study was conducted on pediatric patients from February to August, 2019, in University of Gondar Comprehensive Specialized Hospital (UOGCSH). Data were entered and analyzed with SPSS version 20. Variables with P value less than <0.2 in bivariate analysis were fitted into the multivariable logistic regression analysis to identify factors associated with laryngospasm. Both crude and adjusted odds ratio with 95% CI were calculated to show strength of association. In multivariable analysis, P value of <0.05 was considered as statistically significant.

Results

The incidence of laryngospasm among pediatric patients who underwent surgery under GA was 57 (18.4%). Of this, 34 (59.6%), 12 (21.1%), and 11 (19.3%) happened during emergence, maintenance, and induction phases of GA, respectively. In multivariable analysis, airway anomalies (AOR: 14.64, 95% CI: 1.71, 125.04), secretion (AOR: 2.45, 95% CI: 1.19, 5.06), attempts of airway devices (AOR: 2.47, 95% CI: 1.16, 5.22), upper respiratory tract infection (AOR: 2.91, 95% CI: 1.008, 8.41), and inadequate depth of anesthesia (AOR: 7.92, 95% CI: 2.7, 23.22) were significantly associated with incidence of laryngospasm.

Conclusions

Laryngospasm can occur at any phase of the anesthetic. At UOGCSH, the overall rate of laryngospasm was 18.4%, with the vast majority of episodes occurring on emergence. Inadequate depth of anesthesia, URTI, airway anomalies, multiple attempts of airway devices, and oropharyngeal secretion were predictors of laryngospasm. So, added vigilance is needed in patients with URTI, airway anomalies, or those who require multiple attempts at airway device insertion. Prompt clearing of airway secretions and adequate depth of anesthesia may help to prevent laryngospasm. Since the majority of our patients received an IV induction, endotracheal intubation, and maintenance with halothane, caution must be taken in extrapolating these results to other patient populations.

Perioperative laryngospasm management in paediatrics: a high-fidelity simulation study

Aim

Paediatric anaesthesia is a very specialised domain lacking training during the traditional curriculum. The laryngospasm is a stressful and life-threatening event that requires immediate action. The main objective of this study was to assess the effect of knowledge of a simple algorithm on the management of laryngospasm by trainee anaesthetists and nurse anaesthetists during a high-fidelity simulation session.

Method

Residents in paediatric anaesthesia and training nurse anaesthetists with similar curriculum were randomly allocated to undergo a simulation session of laryngospasm with the help of a simple algorithm administered to them 5 min before the simulation session (group A) or as taught in their curriculum (group C). The primary endpoint was the assessment score of laryngospasm management using 10 technical items (validated in experienced paediatric anaesthetists). Secondary endpoints were: the non-technical skills using the Anaesthetists' Non-Technical Skills (ANTS) score and timing of critical management steps. The correlation between the technical and non-technical scores was also studied. Data are expressed as median (range).

Results

72 participants (18 teams in each group) were included in this study. There was a statistically significant difference between group A and C on the primary endpoint: 8.5 (2–10) vs 5 (2–8), respectively (p<0.0001). There was also a significant difference between the two groups for the ANTS score 12 (7–16) vs 8 (6–12), respectively (p<0.0001). No difference in timing of management was observed. Finally, there was a strong correlation between the technical skills and all the non-technical skills categories in the A group.

Conclusion

A simple algorithm improved the technical and non-technical skills of students during the management of a simulated laryngospasm.

Effect of using the Suction Above Cuff Endotracheal Tube (SACETT) on postoperative respiratory complications in rhinoplasty: a randomized prospective controlled trial

Background: The Suction Above Cuff Endotracheal Tube (SACETT) has a dorsal port above the cuff designed to enable the continuous or intermittent suctioning of secretions from the subglottic space. Thus, it facilitates the suctioning of excessive secretions above the cuff and around the glottis.

Objectives: In this study, we investigated the effect of the using the SACETT on laryngospasm and postoperative complications in rhinoplasty operations.

Methods: This randomized controlled clinical trial enrolled 132 patients undergoing rhinoplasty. The patients were randomly divided into two groups: Suction above Cuff Endotracheal Tube (n=66; Group SA) and classic endotracheal tube (n=66; Group C). Complications following general anesthesia were statistically analyzed among the two groups.

Results: The incidence of postoperative laryngospasm (p=0.02) and respiratory complications was found to be lower in Group SA than in Group C. In addition, the incidence of agitation (p=0.035), postoperative nausea, and vomiting (PONV) (p=0.041), which required antiemetic drug administration, swallowing difficulty (p=0.012), and sore throat (p=0.027) were found to be lower in Group SA than in Group C.

Conclusion: We suggest that using the SACETT in rhinoplasty reduces the incidence of postoperative respiratory complications as well as the incidence of agitation, sore throat, swallowing difficulty, and PONV.

Clinical Trial Number: NCT03584503

Office-Based Anesthesia: Safety and Outcomes in Pediatric Dental Patients

The number of children with caries requiring general anesthesia to achieve comprehensive dental care and the demand for dentist anesthesiologists to provide ambulatory anesthesia for these patients is increasing. No current published studies examine the safety and outcomes of ambulatory anesthesia performed by dentist anesthesiologists for dental procedures in pediatric patients, and there is no national requirement for reporting outcomes of these procedures. In 2010, the Society for Ambulatory Anesthesia Clinical Outcomes Registry was developed. This Web-based database allows providers of ambulatory anesthesia to track patient demographics and various outcomes of procedures. Our study is a secondary analysis of data collected in the registry over a 4-year period, 2010-2014. Of the 7041 cases reviewed, no cases resulted in serious complications, including death, anaphylaxis, aspiration, cardiovascular adverse events, or neurologic adverse events. Of the 7041 cases reviewed, 196 (3.0%) resulted in a predischarge or postdischarge adverse event. The predischarge adverse event occurring with the highest frequency was laryngospasm, occurring in 35 cases (0.50%). The postdischarge adverse event occurring with the highest frequency was nausea, reported by 99 patients (5.0%). This study provides strong clinical outcomes data to support the safety of office-based anesthesia as performed by dentist anesthesiologists in the treatment of pediatric dental patients.

Pulmonary edema post-adenotonsillectomy in children

Post-adenotonsillectomy pulmonary edema (pATPE) is a life-threatening condition that necessitates immediate clinical intervention. The early diagnosis and detection of the signs of this condition is vital to its treatment and patient outcome. The purpose of this review article is to present epidemiological data on the prevalence of pATPE, and address the mechanisms of development, types, etiology, pathophysiology, and management of pATPE. In order to minimize postoperative intensive care unit admission rates of pATPE, utilization of preoperative clinical assessment, operative/postoperative monitoring tools, and procedural precautions are discussed.

Anaesthesia for adenotonsillectomy: An update

Adenotonsillectomy remains one of the most common surgical procedures carried out in children. Though a commonly performed procedure, it poses a great challenge to the surgeon as well as the anaesthesiologist and is associated with a substantially increased risk of morbidity and mortality. In the post-operative period, it poses threats such as post-tonsillectomy bleeding and airway obstruction if not diagnosed and treated promptly. Various recent advances in airway management and early detection of post-operative complications have been made to reduce the sequelae associated with tonsillectomy. In this article, we have reviewed the various techniques, complications and recent advances, which have evolved in the anaesthetic technique related to adenotonsillectomy.

The effects of propofol, ketamine and combination of them in prevention of coughing and laryngospasm in patients awakening from general anesthesia: A randomized, placebo-controlled, double blind clinical trial

BACKGROUND

Coughing and laryngospasm are undesirable outcomes occurring during emergence from general anesthesia. We compared the effect of small doses of propofol, ketamine and a combination of them on the occurrence and severity of coughing and laryngospasm in patients awakening from general anesthesia.

MATERIALS AND METHODS

160 patients who were scheduled to undergo operations under general anesthesia were randomly assigned to one of the following groups, 40 in each group: propofol group (0.25 mg/kg intravenous (IV) propofol), ketamine group (0.25 mg/kg IV ketamine), combination group (0.25 mg/kg IV propofol, and 0.25 mg/kg IV ketamine) and control (0.1 ml/kg IV saline). Drugs were administered before extubation at previously defined time. Presence and severity of coughing and laryngospasm were recorded within twominutes after extubation.

RESULTS

The presence of coughing in the combination group (27.5%) was less than that in other groups; also it was less frequent in the propofol group (57.5%) than the control (82.5%) (all P < 0.05). But the incidence did not differ between the propofol and the ketamine (70%) group; nor did it differ between the ketamine and control groups (P = 0.356 and P = 0.121, respectively). The cases with severe coughing (grade 3) in the combination group (none) were significantly less than in the propofol (four) and the control groups (seven) (P = 0.040 and P = 0.006 respectively). There was no significant difference between the groups in frequency of laryngospasm.

CONCLUSION

Administration of propofol or combination of propofol and ketamine decreases the incidence of post extubation coughing. This combination can also decrease severe cases.

Continuous positive airway pressure with pressure support ventilation is effective in treating acute-onset bilateral recurrent laryngeal nerve palsy

Acute bilateral recurrent laryngeal nerve injury leading to acute vocal cord paralysis (VCP) is a serious complication of head and neck surgery, often requiring emergent surgical intervention. Although well documented, its presentation may be sudden and unexpected, occurring despite lack of obvious intraoperative nerve injury. There is limited literature on airway management strategies for patients with acute bilateral VCP before attaining a secure airway. We report a case of acute VCP that was successfully treated with continuous positive airway pressure via facemask ventilation. This effective temporizing strategy allowed clinicians to plan and prepare for tracheostomy, minimizing potential complications.

Pediatric emergencies

It is important that pediatric critical care nurses possess a thorough understanding of their patient and be able to provide exceptional care, especially during emergent situations in the operating room. This care is accomplished by assessing the pediatric patient, dosing medications accurately and effectively, and performing effective Pediatric Advanced Life Support. Pediatric patients present with unique anatomy, physiology, and pathophysiology. Emergencies are reviewed according to organ system, with a focus on definition, presentation, pathophysiology, management, and special considerations.

Interventions guided by analysis of quality indicators decrease the frequency of laryngospasm during pediatric anesthesia

INTRODUCTION

Clinical outcomes in pediatric anesthesia have improved significantly over the last 20-30 years but unexpected laryngospasm that is difficult to treat can still result in patient morbidity, increased postoperative medical management and unnecessary hospital admission. The incidence of laryngospasm in pediatric anesthesia is difficult to determine with incidences from 0.9% to as high as 14% quoted in the literature. Clinical experience in our institution suggests that laryngospasm is one of the more frequent unanticipated complications that occur under general anesthesia. Therefore, we applied quality improvement (QI) methodology to: (i) identify the etiology and contributing factors that lead to unanticipated incidents during pediatric anesthesia care; and (ii) decrease the incidence of laryngospasm during pediatric anesthesia care by focusing on awareness, preparedness, education and knowledge translation.

MATERIALS & METHODS

We conducted a 30-month improvement project. Twelve months of baseline data describing unanticipated events during pediatric anesthesia care were collected prospectively in a single institution. Data were analyzed to identify leading causes of these unanticipated events and to identify key drivers to improve overall quality of care. Interventions focused on raising awareness of the impact of laryngospasm on quality of patient care, knowledge dissemination and the creation of a knowledge translation tool to encourage future early learning. The primary objective was to decrease the incidence of unanticipated calls for help due to laryngospasm by 50% over a 12-month period.

RESULTS

During the 12-month baseline data period, laryngospasm was responsible for 33 instances (50%) of the 65 'calls for help' identified. The incidence of laryngospasm for which help was sought was 0.25% of all anesthetics performed during the baseline data period. After the introduction of our interventions, 16 (24%) of the 68 'calls for help' over the subsequent 16 months were attributed to laryngospasm. The incidence of laryngospasm for which help was sought during the second time period was 0.09% of all anesthetics performed.

CONCLUSIONS

We applied QI methodology to identify potential improvements in the quality of anesthesia care we deliver to our patients. By designing a number of key drivers and interventions specifically focused on laryngospasm, we decreased the incidence of unanticipated calls for help due to laryngospasm by 50% and maintained this improvement to clinical care across a 12-month period.

Incidence and causes of perioperative endotracheal reintubation in children: a review of 28,208 anesthetics

OBJECTIVES/AIM

To determine the incidence, risk factors, and causes of endotracheal reintubation in children and identify methods to reduce the occurrence.

BACKGROUND

Reintubation during the perioperative period is a serious and potentially preventable adverse event that can result in significant morbidity.

METHODS

A total of 28,208 anesthetics were delivered to pediatric patients at our institution between May 2006 and May 2009. Reintubations were identified with our quality assurance (QA) surveillance database coupled with chart review by our QA nurse. Cases were classified as planned versus inadvertent extubations, and adverse events were assessed.

RESULTS

We discovered 27 cases of reintubation with an incidence of 9.6 : 10,000 anesthetics. Reintubated patients were found to be younger than the general population (P = 0.001) with a high rate of comorbid disease. While most reintubations could be attributed to respiratory causes, 30% were attributed to inadvertent displacement of the endotracheal tube. No mortalities were seen, but 22% of patients needed resuscitative medications and 7% received chest compressions. Of the patients who failed planned extubations, 53% were left intubated with an average duration of postoperative intubation of 2.4 ± 1.9 days.

CONCLUSIONS

The incidence of endotracheal reintubation in children is low, but can result in significant morbidity. Because of the high frequency of inadvertent extubation, a significant number of reintubations could be prevented with greater care during transfer of patients with endotracheal tubes, and in procedures near the airway. Increased vigilance in younger children is also recommended as children under 3 years old required the majority of the reintubations.

Pulmonary delivery of dry powders to rats: tolerability limits of an intra-tracheal administration model

The inhaled route is increasingly developed to deliver locally acting or systemic therapies, and rodent models are used to assess tolerance before clinical studies. Endotracheal intubation of rats with a probe which generates powder aerosols enables controlled administration of drug directly into the respiratory tract. However, preliminary observations of intratracheal powder administration procedures have raised concerns with regard to pulmonary safety. The aim of the present work was to evaluate the safety of intra-tracheal administration of dry powder in a rat model. Sixty animals were administered various volumes of air alone, lactose or magnesium stearate through a Microsprayer(®) (Pencentury, USA). The mass of powder actually delivered to each animal was calculated. Rats were sacrificed immediately after administration, and the lungs, trachea and larynx were removed and examined for gross pathology. The mass of powder delivered varied, the full dose being rarely delivered. About one third of the administration procedures resulted in respiratory failure, and macroscopic pulmonary lesions were observed in about 55% of animals. Lung damages were observed with air alone, lactose and magnesium stearate. In conclusion, artifacts observed with this technique may limit the relevance of the model. These observations are particularly important in the context of regulatory toxicity studies.

The influence of perioperative factors on primary severe hypospadias repair

Hypospadias is one of the most common congenital malformations of the male genitalia. Severe cases present with associated curvature greater than 30° and the meatus opening proximally to the penoscrotal junction. The perioperative management of patients with primary severe hypospadias is variable. Systematic evaluation of the upper urinary tract and the search for enlarged prostatic utricles seem unnecessary in patients with isolated primary severe hypospadias, and should be limited to severe cases with associated extraurinary malformations. Detection of a disorder of sex development is key for gender assignment and prognosis, but the identification of cases warranting a full work-up and the influence of such a diagnosis on the success of hypospadias repair is controversial. Preoperative hormonal stimulation allows for penile growth irrespective of the administration route. Associated morbidity is minimal, but its influence on the success of surgery is still unknown. An age of 6-18 months is generally recommended for surgery, but no trial data support this policy. Second-layer coverage of the urethroplasty and postoperative urinary drainage seem to reduce the complications of surgery, whereas postoperative antibiotic prophylaxis and type of dressing have minimal impact on surgical success. Overall, most interventions are based on weak evidence, and their influence on the outcomes of repair is ill-defined. Clinicians should be made aware of the evidence supporting any single intervention in order to standardize their management policies. We hope the issues outlined here will prompt researchers to design new studies to address the clinically relevant questions.

Effect of a small dose of propofol or ketamine to prevent coughing and laryngospasm in children awakening from general anesthesia

BACKGROUND

Coughing during emergence from general anesthesia may be detrimental in children. We compared the effect of a small dose of propofol or ketamine administered at the end of sevoflurane anesthesia on the incidence or severity of coughing in children undergoing a minimal invasive operation.

METHODS

One hundred and eighteen children aged between 3 and 15 years, American Society of Anesthesiologists (ASA) status I, were enrolled in this randomized double blind study. Anesthesia was induced with propofol or ketamine and maintained with sevoflurane in N(2)O/O(2). Each group received propofol 0.25 mg/kg or ketamine 0.25 mg/kg and the control group received saline 0.1 ml/kg. The decision to perform tracheal extubation was based on specified criteria, including the resumption of spontaneous respiration. During emergence from anesthesia and extubation, coughing was observed and graded at predefined times.

RESULTS

The incidence of emergence without coughing was higher in the propofol group than in the ketamine and control group (19%, 11% and 6%, respectively), whereas the incidence of severe coughing was higher in the control group than in propofol and ketamine group (17.14%, 10.0% and 6.98%, respectively).

CONCLUSIONS

The addition of propofol 0.25 mg/kg decreased the incidence of coughing after sevoflurane general anesthesia in children undergoing non-painful procedures.

Neuromuscular block and current treatment strategies for its reversal in children

Even though neuromuscular blocking agents are an essential part of balanced anesthesia and the risks of residual paralysis are well documented, many anesthetists seldomly monitor neuromuscular block. Classical reversal agent neostigmine is unable to antagonise a deep neuromuscular block and is rather slow to antagonise even a moderate block. These caveats may have introduced a practice to use muscle relaxants mainly for an endotracheal intubation. This review presents current views on the effects of muscle relaxants and their reversal agents in pediatric patients. This may help clinicians to reconsider the value of muscle relaxants during anesthesia in children.

[Laryngospasm]

BACKGROUND AND OBJECTIVES

Airways management is fundamental for anesthesiologists, especially during induction of anesthesia and after extubation, when laryngeal spasm is more common. The anesthesiologist should know pharyngeal-laryngeal physiology and the risk factors for airways obstruction, since this is a potentially severe complication with a multifactorial etiology that can develop during anesthesia and whose consequences can be catastrophic. A delay in the diagnosis or treatment and its evolution can lead to hypoxemia, acute pulmonary edema, and, eventually, death of the patient. In this context, the objective of this report was to review the measures that should be taken in cases of laryngospasm because adequate oxygenation and ventilation may be compromised in this situation.

CONTENTS

This review article presents the mechanisms of airways management, discussing the most relevant aspects and etiology, pathophysiology, treatment, and prevention of laryngospasm.

CONCLUSIONS

The literature has several recommendations on the treatment or prevention of laryngospasm, but none of them is completely effective. Due to its severity, further studies on measures to prevent this complication are necessary.

Current world literature

This bibliography is compiled by clinicians from the journals listed at the end of this publication. It is based on literature entered into our database between 1 February 2008 and 31 January 2009 (articles are generally added to the database about two and a half months after publication). In addition, the bibliography contains every paper annotated by reviewers; these references were obtained from a variety of bibliographic databases and published between the beginning of the review period and the time of going to press. The bibliography has been grouped into topics that relate to the reviews in this issue.