Modeling Recurrence in Idiopathic Subglottic Stenosis With Mobile Peak Expiratory Flow

OBJECTIVES/HYPOTHESIS

We sought to establish normative peak expiratory flow (PEF) data for patients with idiopathic subglottic stenosis (iSGS), evaluate whether immediate changes in PEF after a procedure predict long-term treatment response, and test if a decline in longitudinal PEF is associated with disease recurrence.

STUDY DESIGN

International, prospective, 3-year multicenter cohort study of 810 patients with untreated, newly diagnosed, or previously treated iSGS.

METHODS

iSGS patients consented and enrolled in the North American Airway Collaborative (NoAAC) iSGS¹⁰⁰⁰ cohort recorded PEF data on a mobile smartphone app. Cox regression tested the associations between the magnitude of postoperative PEF improvement and longitudinal 90-day PEF decline with the risk of disease recurrence.

RESULTS

Within the NoAAC iSGS¹⁰⁰⁰ cohort, 810 patients participated in a 3-year prospective study comparing surgical treatment efficacy and 385 had appropriate PEF measurements and follow-up data. Of those patients, 42% (161/385) required at least one operation during study follow-up. The mean PEF preceding operative intervention was 241 L/min (95% confidence interval [CI]: 120-380) corresponding to a predicted PEF of 52%. The mean increase in PEF following a procedure was 111 L/min (95% CI: 96-125 L/min). Interestingly, the magnitude of immediate PEF improvement was not predictive of disease recurrence (hazard ratio [HR] for 100 L/min increase = 0.90, 95% CI: 0.60-1.00). However, recurrence was associated with the magnitude of PEF decline over 90 days (30% vs. 10% decline, HR = 2.2, 95% CI: 1.5-3.0).

CONCLUSIONS

We provide normative PEF data on a large iSGS patient cohort. The degree of PEF improvement immediately after surgery was not associated with a longer procedure-free interval. However, a 30% decline in PEF over 90 days was associated with elevated risk of disease recurrence.

LEVEL OF EVIDENCE

2 Laryngoscope, 2021.

Management of traumatic laryngotracheal separation: Case series and review

Laryngotracheal separation injuries are a rare but serious condition, as survival from such injuries relies on proper airway management. As a result, recommendations for management have been based on small case reports and expert opinion. We reviewed our last 10 years of experience with managing laryngotracheal separation injuries and identified 6 cases for chart review. Awake tracheostomy or videolaryngobronchoscopy was used in each case to initially obtain the airway. Surgical repair was then performed immediately using nonabsorbable monofilament suture or a miniplate, and a low fenestrated tracheostomy was placed. All of our patients who followed up were decannulated, eating regular diets, and had satisfactory voice quality at 3 months postoperatively. Review of the literature revealed that, while management strategies have changed over time, treatment still varies widely depending on surgeon preference and the details of each injury. Outcomes from our series suggest that our described techniques and management strategies can be used with good outcomes. We believe that this is due to securing a safe airway, early surgical intervention with no unnecessary tissue dissection, effective reconstruction of the airway, and the fenestrated tracheostomy technique.

First-attempt success rate of video laryngoscopy in small infants (VISI): a multicentre, randomised controlled trial

BACKGROUND

Orotracheal intubation of infants using direct laryngoscopy can be challenging. We aimed to investigate whether video laryngoscopy with a standard blade done by anaesthesia clinicians improves the first-attempt success rate of orotracheal intubation and reduces the risk of complications when compared with direct laryngoscopy. We hypothesised that the first-attempt success rate would be higher with video laryngoscopy than with direct laryngoscopy.

METHODS

In this multicentre, parallel group, randomised controlled trial, we recruited infants without difficult airways abnormalities requiring orotracheal intubation in operating theatres at four quaternary children's hospitals in the USA and one in Australia. We randomly assigned patients (1:1) to video laryngoscopy or direct laryngoscopy using random permuted blocks of size 2, 4, and 6, and stratified by site and clinician role. Guardians were masked to group assignment. The primary outcome was the proportion of infants with a successful first attempt at orotracheal intubation. Analysis (modified intention-to-treat [mITT] and per-protocol) used a generalised estimating equation model to account for clustering of patients treated by the same clinician and institution, and adjusted for gestational age, American Society of Anesthesiologists physical status, weight, clinician role, and institution. The trial is registered at ClinicalTrials.gov, NCT03396432.

FINDINGS

Between June 4, 2018, and Aug 19, 2019, 564 infants were randomly assigned: 282 (50%) to video laryngoscopy and 282 (50%) to direct laryngoscopy. The mean age of infants was 5·5 months (SD 3·3). 274 infants in the video laryngoscopy group and 278 infants in the direct laryngoscopy group were included in the mITT analysis. In the video laryngoscopy group, 254 (93%) infants were successfully intubated on the first attempt compared with 244 (88%) in the direct laryngoscopy group (adjusted absolute risk difference 5·5% [95% CI 0·7 to 10·3]; p=0·024). Severe complications occurred in four (2%) infants in the video laryngoscopy group compared with 15 (5%) in the direct laryngoscopy group (-3·7% [-6·5 to -0·9]; p=0·0087). Fewer oesophageal intubations occurred in the video laryngoscopy group (n=1 [<1%]) compared with in the direct laryngoscopy group (n=7 [3%]; -2·3 [-4·3 to -0·3]; p=0·028).

INTERPRETATION

Among anaesthetised infants, using video laryngoscopy with a standard blade improves the first-attempt success rate and reduces complications.

FUNDING

Anaesthesia Patient Safety Foundation, Society for Airway Management, and Karl Storz Endoscopy.

Changing the view: Video versus direct laryngoscopy for intubation in the pediatric emergency department

The aim of this study was to compare the success of first-attempt tracheal intubation in pediatric patients >1-year old performed using video versus direct laryngoscopy and compare the frequency of tracheal intubation-associated events and desaturation among these patients.Prospective observational cohort study conducted in an Academic pediatric tertiary emergency department. We compared 50 children intubated with Mcgrath Mac video laryngoscope (VL group) and an historical series of 141 children intubated with direct laryngoscopy (DL group). All patients were aged 1 to 18 years.The first attempt success rates were 68% (34/50) and 37.6% (53/141) in the VL and DL groups (P < .01), respectively. There was a lower proportion of tracheal intubation-associated events in the VL group (VL, 31.3% [15/50] vs DL, 67.8% [97/141]; P < .01) and no significant differences in desaturation (VL, 35% [14/50] vs DL 51.8% [72/141]; P = .06). The median number of attempts was 1 (range, 1-5) for the VL group and 2 (range, 1-8) for the DL group (P < .01). Multivariate logistic regression showed that video laryngoscope use was associated with higher chances of first-attempt intubation with an odds ratio of 4.5 (95% confidence interval, 1.9-10.4, P < 0.01).Compared with direct laryngoscopy, VL was associated with higher success rates of first-attempt tracheal intubations and lower rates of tracheal intubation-associated events.

Is Vocal Cord Assessment before Total Thyroidectomy Required for All Patients?

We investigated whether laryngoscopy should be performed before total thyroidectomy on all patients without a history of neck surgery. A total of 2523 patients who underwent total thyroidectomy between January 1, 2013, and March 18, 2018, were retrospectively examined. Preoperative vocal cord examination was performed on 2070 of these patients by the otorhinolaryngology department using indirect laryngoscopy. Patients with a history of neck or thyroid surgery were not included in the study. The patients were evaluated in terms of age, gender, symptom (hoarseness/dyspnea), comorbidity, surgical history, biopsy, nodule diameter, pathological diagnosis, and tracheal deviation. Preoperative vocal cord paralysis was detected in 0.8 per cent of the patients (17/2070). Four patients (23.5%) were male and 13 patients (76.5%) were female. The mean age was 62 (range, 25-82) years. Seven of the 17 patients (41%) were symptomatic, with complaints of dyspnea in five and hoarseness in two. The univariate analysis revealed that a nodule diameter >30 mm and the presence of dyspnea were associated with vocal cord damage. Furthermore, the multivariate analysis showed that dyspnea alone was an independent variable (P = 0.011). It is recommended that preoperative vocal cord evaluation should be performed only in patients with severe symptoms, such as dyspnea.

Use of the pediatric intensive care unit for post-procedural monitoring in young children following microlaryngobronchoscopy: Impact on resource utilization and hospital cost

OBJECTIVE

To assess the frequency of post-procedural complications, medical interventions, and hospital costs associated with microlaryngobronchoscopy (MLB) in children prophylactically admitted for pediatric intensive care unit (PICU) monitoring for age ≤ 2 years.

METHODS

We performed a single-center, retrospective, descriptive study within a 44-bed PICU in a stand-alone, tertiary, pediatric referral center. Inclusion criteria were age ≤2 years and pre-procedural selection of prophylactic PICU monitoring after MLB between January 2010 and December 2015. Children were excluded for existing tracheostomy, if undergoing concurrent non-otolaryngeal procedures, or if intubated at the time of PICU admission. Primary outcomes were the development of major and minor procedural complications and medical rescue interventions. Secondary outcomes were hospital cost and length of stay (LOS).

RESULTS

One hundred and eight subjects met inclusion criteria with a median age of 5.3 (IQR: 2.6-10.9) months. A majority (86%) underwent therapeutic instrumentation in addition to diagnostic MLB. There were no observed major complications or rescue interventions. Minor complications were noted within 5 h of monitoring and included isolated stridor (24%), desaturation <90% (10%), and nausea/emesis (8%). Minor interventions included supplemental oxygen via regular nasal cannula (39%), single-dose inhaled racemic epinephrine (19%), single-dose systemic corticosteroids (19%), or high flow nasal cannula (HFNC) therapy (4%). Save for two cases of HFNC, interventions were completed or discontinued within 5 h. Median PICU LOS was 1.1 days and median cost was $9650 (IQR: $8235- $14,861) per encounter. Estimated cost of same day observation in our post anesthesia care unit (PACU) following MLB without PICU admission is $1921 per encounter.

CONCLUSIONS

In children ≤ 2 years of age prophylactically admitted for PICU observation, we did not observe severe complications or major interventions after MLB. Minor interventions and complications were noted early during post-procedural monitoring. PICU monitoring was substantially more expensive than same-day PACU observation. Young age as the sole criteria for prophylactic PICU monitoring after diagnostic or therapeutic MLB may be unjustified when comparable, cost-conscious care can be achieved in a PACU setting. Prior to pre-procedural selection of PICU monitoring, we recommend a broad contextual risk assessment including a review of comorbidities, operative plan, and intended anesthetic exposure.

The association of body mass index with difficult tracheal intubation management by direct laryngoscopy: a meta-analysis

BACKGROUND

Obesity is a serious disorder and may bring about many difficulties of perioperative management. A systematic review was conducted to assess the association between obesity and difficult intubation.

METHODS

We searched electronic databases for related reviews and references of meta-analyses on August 14, 2017. The databases of PubMed, Embase, and the Cochrane controlled trials register were searched compared obese with non-obese patients in which difficult intubation rate of the adult population were retrieved. Patients with a BMI ≥ 30 kg·m- 2 were considered obese. The primary outcome was difficult tracheal intubation; secondary outcomes were the rates of difficult laryngoscopy and Mallampati score ≥ 3. This review included papers published from 1998 to 2015.

RESULTS

This review included 204,303 participants in 16 studies. There was a statistically significant association between obesity and risk of difficult tracheal intubation (pooled RR = 2.04, 95% CI: 1.16-3.59, p = 0.01; I2 = 71%, p = 0.008, Power = 1.0). It also showed significantly association between obesity and risk of difficult laryngoscopy (pooled RR = 1.54, 95% CI: 1.25-1.89, p < 0.0001; I2 = 45%, p = 0.07, Power = 1.0), obesity and risk of Mallampati score ≥ 3 (pooled RR = 1.83, 95% CI: 1.24-2.69, p = 0.002; I2 = 81%, p < 0.00001, Power = 0.93). However, there were no association of obesity and risks of difficult intubation compared with non-obesity in the cohort studies (pooled RR = 3.41, 95% CI: 0.88-13.23, p = 0.08; I2 = 50%, p = 0.14) and the elective tracheal intubation (pooled RR = 2.31, 95% CI: 0.76-6.99, p = 0.14; I2 = 73%, p = 0.01), no associated with an increased risk of difficult laryngoscopy in the sniffing position (pooled RR = 2.00, 95% CI: 0.97-4.15, p = 0.06; I2 = 67%, p = 0.03).

CONCLUSION

Obesity was associated with an increased risk of difficult intubation, difficult laryngoscopy and Mallampati score ≥ 3 in adults patients undergoing general surgical procedures. However, there were no association of obesity and risks of difficult intubation compared with non-obesity in the cohort studies and the elective tracheal intubation, no associated with an increased risk of difficult laryngoscopy in the sniffing position. Future analyses should explore the association of BMI and difficult airway.

Airway physical examination tests for detection of difficult airway management in apparently normal adult patients

BACKGROUND

The unanticipated difficult airway is a potentially life-threatening event during anaesthesia or acute conditions. An unsuccessfully managed upper airway is associated with serious morbidity and mortality. Several bedside screening tests are used in clinical practice to identify those at high risk of difficult airway. Their accuracy and benefit however, remains unclear.

OBJECTIVES

The objective of this review was to characterize and compare the diagnostic accuracy of the Mallampati classification and other commonly used airway examination tests for assessing the physical status of the airway in adult patients with no apparent anatomical airway abnormalities. We performed this individually for each of the four descriptors of the difficult airway: difficult face mask ventilation, difficult laryngoscopy, difficult tracheal intubation, and failed intubation.

SEARCH METHODS

We searched major electronic databases including CENTRAL, MEDLINE, Embase, ISI Web of Science, CINAHL, as well as regional, subject specific, and dissertation and theses databases from inception to 16 December 2016, without language restrictions. In addition, we searched the Science Citation Index and checked the references of all the relevant studies. We also handsearched selected journals, conference proceedings, and relevant guidelines. We updated this search in March 2018, but we have not yet incorporated these results.

SELECTION CRITERIA

We considered full-text diagnostic test accuracy studies of any individual index test, or a combination of tests, against a reference standard. Participants were adults without obvious airway abnormalities, who were having laryngoscopy performed with a standard laryngoscope and the trachea intubated with a standard tracheal tube. Index tests included the Mallampati test, modified Mallampati test, Wilson risk score, thyromental distance, sternomental distance, mouth opening test, upper lip bite test, or any combination of these. The target condition was difficult airway, with one of the following reference standards: difficult face mask ventilation, difficult laryngoscopy, difficult tracheal intubation, and failed intubation.

DATA COLLECTION AND ANALYSIS

We performed screening and selection of the studies, data extraction and assessment of methodological quality (using QUADAS-2) independently and in duplicate. We designed a Microsoft Access database for data collection and used Review Manager 5 and R for data analysis. For each index test and each reference standard, we assessed sensitivity and specificity. We produced forest plots and summary receiver operating characteristic (ROC) plots to summarize the data. Where possible, we performed meta-analyses to calculate pooled estimates and compare test accuracy indirectly using bivariate models. We investigated heterogeneity and performed sensitivity analyses.

MAIN RESULTS

We included 133 (127 cohort type and 6 case-control) studies involving 844,206 participants. We evaluated a total of seven different prespecified index tests in the 133 studies, as well as 69 non-prespecified, and 32 combinations. For the prespecified index tests, we found six studies for the Mallampati test, 105 for the modified Mallampati test, six for the Wilson risk score, 52 for thyromental distance, 18 for sternomental distance, 34 for the mouth opening test, and 30 for the upper lip bite test. Difficult face mask ventilation was the reference standard in seven studies, difficult laryngoscopy in 92 studies, difficult tracheal intubation in 50 studies, and failed intubation in two studies. Across all studies, we judged the risk of bias to be variable for the different domains; we mostly observed low risk of bias for patient selection, flow and timing, and unclear risk of bias for reference standard and index test. Applicability concerns were generally low for all domains. For difficult laryngoscopy, the summary sensitivity ranged from 0.22 (95% confidence interval (CI) 0.13 to 0.33; mouth opening test) to 0.67 (95% CI 0.45 to 0.83; upper lip bite test) and the summary specificity ranged from 0.80 (95% CI 0.74 to 0.85; modified Mallampati test) to 0.95 (95% CI 0.88 to 0.98; Wilson risk score). The upper lip bite test for diagnosing difficult laryngoscopy provided the highest sensitivity compared to the other tests (P < 0.001). For difficult tracheal intubation, summary sensitivity ranged from 0.24 (95% CI 0.12 to 0.43; thyromental distance) to 0.51 (95% CI 0.40 to 0.61; modified Mallampati test) and the summary specificity ranged from 0.87 (95% CI 0.82 to 0.91; modified Mallampati test) to 0.93 (0.87 to 0.96; mouth opening test). The modified Mallampati test had the highest sensitivity for diagnosing difficult tracheal intubation compared to the other tests (P < 0.001). For difficult face mask ventilation, we could only estimate summary sensitivity (0.17, 95% CI 0.06 to 0.39) and specificity (0.90, 95% CI 0.81 to 0.95) for the modified Mallampati test.

AUTHORS' CONCLUSIONS

Bedside airway examination tests, for assessing the physical status of the airway in adults with no apparent anatomical airway abnormalities, are designed as screening tests. Screening tests are expected to have high sensitivities. We found that all investigated index tests had relatively low sensitivities with high variability. In contrast, specificities were consistently and markedly higher than sensitivities across all tests. The standard bedside airway examination tests should be interpreted with caution, as they do not appear to be good screening tests. Among the tests we examined, the upper lip bite test showed the most favourable diagnostic test accuracy properties. Given the paucity of available data, future research is needed to develop tests with high sensitivities to make them useful, and to consider their use for screening difficult face mask ventilation and failed intubation. The 27 studies in 'Studies awaiting classification' may alter the conclusions of the review, once we have assessed them.

Cross-over study of novice intubators performing endotracheal intubation in an upright versus supine position

There are a number of potential physical advantages to performing orotracheal intubation in an upright position. The objective of this study was to measure the success of intubation of a simulated patient in an upright versus supine position by novice intubators after brief training. This was a cross-over design study in which learners (medical students, physician assistant students, and paramedic students) intubated mannequins in both a supine (head of the bed at 0°) and upright (head of bed elevated at 45°) position. The primary outcome of interest was successful intubation of the trachea. Secondary outcomes included log time to intubation, Cormack-Lehane view obtained, Percent of Glottic Opening score, provider assessment of difficulty, and overall provider satisfaction with the position. There were a total of 126 participants: 34 medical students, 84 physician assistant students, and 8 paramedic students. Successful tracheal intubation was achieved in 114 supine attempts (90.5 %) and 123 upright attempts (97.6 %; P = 0.283). Upright positioning was associated with significantly faster log time to intubation, higher likelihood of achieving Grade I Cormack-Lehane view, higher Percent of Glottic Opening score, lower perceived difficulty, and higher provider satisfaction. A subset of 74 participants had no previous intubation training or experience. For these providers, there was a non-significant trend toward improved intubation success with upright positioning vs supine positioning (98.6 % vs. 87.8 %, P = 0.283). For all secondary outcomes in this group, upright positioning significantly outperformed supine positioning.

Day-care unit for rigid panendoscopy of the upper aerodigestive tract: A study of 436 procedures

OBJECTIVES

To assess the role of day-care management of upper aerodigestive tract (UADT) panendoscopy and to study criteria for conventional hospital admission and reasons for conversion.

PATIENTS AND METHODS

Retrospective study, from January 2011 to May 2013. Inclusion criteria UADT panendoscopy for carcinoma assessment. Study variables, age, gender, tumor location, reason for panendoscopy, TNM stage, previous external radiotherapy, home-to-hospital distance and Apfel, Detsky and ASA scores. A day-care and a conventional admission group were compared using Fisher's test for ASA score, student's test for age and Pearson's chi² test for the other variables.

RESULTS

Four hundred and thirty-six panendoscopies were performed: 252 in day-care, including 4 cases of conversion and 184 with conventional admission. There were no significant differences between groups for age, gender, tumor location, TNM stage, reason for panendoscopy, previous external radiotherapy, home-to-hospital distance or Apfel score. A significant difference was observed for ASA score (P<0.0001) and Detsky score (P=0.03). In 39% of cases, the reason for hospital admission without criteria defined by the French Society of Anesthesia and Intensive Care Medicine (SFAR) and French Health Authority (HAS) was the patient's refusal of day care. In 10% of conventional admissions, day-care was not implemented because of psychosocial factors.

CONCLUSION

Day-care management is appropriate for UADT panendoscopy in selected patients. The reasons for the high rate of patient refusal should be studied.

Videolaryngoscopy versus direct laryngoscopy for tracheal intubation in children (excluding neonates)

BACKGROUND

Direct laryngoscopy is the method currently used for tracheal intubation in children. It occasionally offers unexpectedly poor laryngeal views. Indirect laryngoscopy involves visualizing the vocal cords by means other than obtaining a direct sight, with the potential to improve outcomes. We reviewed the current available literature and performed a meta-analysis to compare direct versus indirect laryngoscopy, or videolaryngoscopy, with regards to efficacy and adverse effects.

OBJECTIVES

To assess the efficacy of indirect laryngoscopy, or videolaryngoscopy, versus direct laryngoscopy for intubation of children with regards to intubation time, number of attempts at intubation, and adverse haemodynamic responses to endotracheal intubation. We also assessed other adverse responses to intubation, such as trauma to oral, pharyngeal, and laryngeal structures, and we assessed vocal cord view scores.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), and trial registers (www.clinicaltrials.gov and www.controlledtrials) in November 2015. We reran the search in January 2017. We added new studies of potential interest to a list of 'Studies awaiting classification' and will incorporate them into formal review findings during the review update. We performed reference checking and citation searching and contacted the authors of unpublished data to ask for more information. We applied no language restrictions.

SELECTION CRITERIA

We included only randomized controlled trials. Participants were children aged 28 days to 18 years. Investigators performed intubations using any type of indirect laryngoscopes, or videolaryngoscopes, versus direct laryngoscopes.

DATA COLLECTION AND ANALYSIS

We used Cochrane standard methodological procedures. Two review authors independently reviewed titles, extracted data, and assessed risk of bias.

MAIN RESULTS

We included 12 studies (803 children) in this review and meta-analysis. We identified three studies that are awaiting classification and two ongoing studies.Trial results show that a longer intubation time was required when indirect laryngoscopy, or videolaryngoscopy, was used instead of direct laryngoscopy (12 trials; n = 798; mean difference (MD) 5.49 seconds, 95% confidence interval (CI) 1.37 to 9.60; I² = 90%; very low-quality evidence). Researchers found no significant differences between direct and indirect laryngoscopy on assessment of success of the first attempt at intubation (11 trials; n = 749; risk ratio (RR) 0.96, 95% CI 0.91 to 1.02; I² = 67%; low-quality evidence) and observed that unsuccessful intubation (five trials; n = 263) was significantly increased in the indirect laryngoscopy, or videolaryngoscopy, group (RR 4.93, 95% CI 1.33 to 18.31; I² = 0%; low-quality evidence). Five studies reported the effect of intubation on oxygen saturation (n = 272; very low-quality evidence). Five children had desaturation during intubation: one from the direct laryngoscopy group and four from the indirect laryngoscopy, or videolaryngoscopy, group.Two studies (n = 100) reported other haemodynamic responses to intubation (very low-quality evidence). One study reported a significant increase in heart rate five minutes after intubation in the indirect laryngoscopy group (P = 0.007); the other study found that the heart rate change in the direct laryngoscopy group was significantly less than the heart rate change in the indirect laryngoscopy, or videolaryngoscopy, group (P < 0.001). A total of five studies (n = 244; very low-quality evidence) looked at evidence of trauma resulting from intubation. Investigators reported that only two children from the direct laryngoscopy group had trauma compared with no children in the indirect laryngoscopy, or videolaryngoscopy, group.Use of indirect laryngoscopy, or videolaryngoscopy, improved the percentage of glottic opening (five trials; n = 256). Studies noted no significant difference in Cormack and Lehane score (C&L) grade 1 (three trials; n = 190; RR 1.06, 95% CI 0.93 to 1.21; I² = 59%).

AUTHORS' CONCLUSIONS

Evidence suggests that indirect laryngoscopy, or videolaryngoscopy, leads to prolonged intubation time with an increased rate of intubation failure when compared with direct laryngoscopy (very low-quality evidence due to imprecision, inconsistency, and study limitations). Review authors had difficulty reaching conclusions on adverse haemodynamic responses and other adverse effects of intubation, as only a few children were reported to have these outcomes. Use of indirect laryngoscopy, or videolaryngoscopy, might lead to improved vocal cord view, but marked heterogeneity between studies made it difficult for review authors to reach conclusions on this outcome.

Video Laryngoscopy vs Direct Laryngoscopy on Successful First-Pass Orotracheal Intubation Among ICU Patients: A Randomized Clinical Trial

IMPORTANCE

In the intensive care unit (ICU), orotracheal intubation can be associated with increased risk of complications because the patient may be acutely unstable, requiring prompt intervention, often by a practitioner with nonexpert skills. Video laryngoscopy may decrease this risk by improving glottis visualization.

OBJECTIVE

To determine whether video laryngoscopy increases the frequency of successful first-pass orotracheal intubation compared with direct laryngoscopy in ICU patients.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial of 371 adults requiring intubation while being treated at 7 ICUs in France between May 2015 and January 2016; there was 28 days of follow-up.

INTERVENTIONS

Intubation using a video laryngoscope (n = 186) or direct laryngoscopy (n = 185). All patients received general anesthesia.

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion of patients with successful first-pass intubation. The secondary outcomes included time to successful intubation and mild to moderate and severe life-threatening complications.

RESULTS

Among 371 randomized patients (mean [SD] age, 62.8 [15.8] years; 136 [36.7%] women), 371 completed the trial. The proportion of patients with successful first-pass intubation did not differ significantly between the video laryngoscopy and direct laryngoscopy groups (67.7% vs 70.3%; absolute difference, -2.5% [95% CI, -11.9% to 6.9%]; P = .60). The proportion of first-attempt intubations performed by nonexperts (primarily residents, n = 290) did not differ between the groups (84.4% with video laryngoscopy vs 83.2% with direct laryngoscopy; absolute difference 1.2% [95% CI, -6.3% to 8.6%]; P = .76). The median time to successful intubation was 3 minutes (range, 2 to 4 minutes) for both video laryngoscopy and direct laryngoscopy (absolute difference, 0 [95% CI, 0 to 0]; P = .95). Video laryngoscopy was not associated with life-threatening complications (24/180 [13.3%] vs 17/179 [9.5%] for direct laryngoscopy; absolute difference, 3.8% [95% CI, -2.7% to 10.4%]; P = .25). In post hoc analysis, video laryngoscopy was associated with severe life-threatening complications (17/179 [9.5%] vs 5/179 [2.8%] for direct laryngoscopy; absolute difference, 6.7% [95% CI, 1.8% to 11.6%]; P = .01) but not with mild to moderate life-threatening complications (10/181 [5.4%] vs 14/181 [7.7%]; absolute difference, -2.3% [95% CI, -7.4% to 2.8%]; P = .37).

CONCLUSIONS AND RELEVANCE

Among patients in the ICU requiring intubation, video laryngoscopy compared with direct laryngoscopy did not improve first-pass orotracheal intubation rates and was associated with higher rates of severe life-threatening complications. Further studies are needed to assess the comparative effectiveness of these 2 strategies in different clinical settings and among operators with diverse skill levels.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02413723.

Office-based lower airway endoscopy (OLAE) in pediatric patients: a high-value procedure

OBJECTIVES

Office-based lower airway endoscopy (OLAE) is not a widespread practice in children due to concerns about its safety and efficacy. In 2003, we reported on OLAE in 105 children presenting with airway symptoms and found it both safe and effective as a diagnostic tool. The current study is a follow-up to the 2003 study that reports on an additional 122 pediatric patients who received OLAE with special attention to the safety and efficacy of the procedure.

METHODS

A retrospective review at a tertiary-quaternary pediatric institution of 122 consecutive pediatric patients in which an airway lesion, by history and initial physical exam, was determined to be present at the level of the supraglottic larynx to the carina. In all patients, airway endoscopy was performed in the office using flexible fiberoptic laryngoscopy (FFL) and the endoscope was passed beyond the glottis to assess the lower airway, including the subglottis, trachea, and carina. The diagnoses were recorded and the number of times each diagnosis was encountered as well as the percent of patients who had each diagnosis was calculated. All cases requiring operating room procedures for further diagnosis or therapy were assessed for office-based and operating room diagnostic agreement. The ease of performing the lower airway assessment and the ease with which the subglottis, trachea, and carina were visualized were graded. An assessment for complications was also performed.

RESULTS

There were no complications with OLAE in any of the 122 patients. The percent of patients rated as having good visualization of anatomic structures were: 97% for visualization of the subglottis, 98% for visualization of the trachea, and 92% for visualization of the carina. In 93% of the cases the procedure was easily performed. There was excellent correlation between OLAE and operative endoscopy.

CONCLUSION

OLAE continues to be a safe, efficacious, and cost-effective tool for the diagnosis of lower airway pathology in pediatric patients.

Using image processing technology combined with decision tree algorithm in laryngeal video stroboscope automatic identification of common vocal fold diseases

This study used the actual laryngeal video stroboscope videos taken by physicians in clinical practice as the samples for experimental analysis. The samples were dynamic vocal fold videos. Image processing technology was used to automatically capture the image of the largest glottal area from the video to obtain the physiological data of the vocal folds. In this study, an automatic vocal fold disease identification system was designed, which can obtain the physiological parameters for normal vocal folds, vocal paralysis and vocal nodules from image processing according to the pathological features. The decision tree algorithm was used as the classifier of the vocal fold diseases. The identification rate was 92.6%, and the identification rate with an image recognition improvement processing procedure after classification can be improved to 98.7%. Hence, the proposed system has value in clinical practices.

The effect of body mass index on intubation success rates and complications during emergency airway management

We evaluated the effect of body mass index (BMI) on intubation success rates and complications during emergency airway management. We retrospectively analyzed an airway registry at an academic medical center. The primary outcomes were the incidence of difficult intubation and complication rates, stratified by BMI. We captured 1,075 (98 %, 1,075/1,102; 95 % CI 97-99) intubations. Four hundred twenty-six patients (40 %) had a normal BMI, 289 (27 %) were overweight, 261 (25 %) were obese, and 77 (7 %) were morbidly obese. In a multivariate analysis, obesity (OR 1.90; 95 % CI 1.04-3.45; p = 0.04), but not morbid obesity (OR 2.18; 95 % CI 0.95-4.99; p = 0.07), predicted difficult intubation. BMI was not predictive of post-intubation complications. Airway management in the morbidly obese differed when compared with lean patients, with less use of rapid sequence intubation and increased use of fiberoptic bronchoscopy in the former. During emergency airway management, difficult intubation is more common in obese patients, and morbidly obese patients are more commonly treated as potentially difficult airways.

First experience of the use of the C-MAC PM videolaryngoscope in a clinical setting by anesthetic nurses: a comparison with anesthetists

BACKGROUND

The Storz C-MAC videolaryngoscope has been found to facilitate endotracheal intubation and to be easy to use by novice users. However, it has never been studied in those who will probably use it most, anesthetists and anesthetic nurses. The aim of the present study was to identify the number of attempts needed before the participants were able to intubate 2 consecutive patients within 30 seconds.

METHODS

Following a didactic session, 22 anesthetists and 21 anesthetic nurses were included in the study and attempted to intubate 184 patients with predicted easy laryngoscopy scheduled to undergo elective surgery. The number of attempts before achieving 2 consecutive successful intubations and time to intubation were recorded for both groups of participants. Perception of ease of use for the device was also recorded.

RESULTS

Overall, anesthetic nurses required more attempts before achieving 2 consecutive successful intubations (5.9 +/- 3.24 vs 2.73+/- 1.67, p < 0.0005). They also had significantly more failures until 2 consecutive successful intubations were achieved, compared to anesthetists (4.1 +/- 2.8 vs 1.32 +/- 1.25, p < 0.0005). A significantly higher percentage of anesthetic nurses required more than 3 attempts before achieving 2 consecutive intubations (75% vs 36%, p = 0.016). Regarding the intubation time, no significant differences were recorded between specialties. Anesthetic nurses assessed the C-MAC as easier to use than anesthetists did.

CONCLUSIONS

This is the first clinical study assessing the use of the C-MAC videolaryngoscope by inexperienced anesthetists and anesthetic nurses indicating that it is easy to learn and to use in their hands.

[Epidemiological aspects of congenital stridor]

The objective of the present work was to study epidemiology of congenital stridor as a leading symptom of laryngeal malformation. The continuous sampling method was employed to perform the retrospective analysis of the growth charts of the patients attending three children's polyclinics in Moscow (9.625 patients born between 2005 and 2009). In addition, the medical histories of 4.623 newborn and breast-fed babies under the age of 1 year admitted to the Department of Newborn and Neonatal Pathology, Saint Vladimir City Children's Clinical Hospital, and 347 patients of the Department of Reconstructive Laryngeal Surgery were analysed. The children with the history of tracheal intubation in the preceding period were excluded from the study. The frequency of congenital stridor annually diagnosed in the aforementioned polyclinics varied from 0.17 to 5.8% compared with 1.5% in the general population. It was 2.21 to 3.14% (mean 2.47%) among the children treated at the Clinical Hospital. In the children under the age of 1 year, congenital malformations accounted for 90.8% of all laryngeal diseases. The principal cause of stridor was shown to be laryngomalacia. This pathology was diagnosed in 91.9% of the cases included in this study. In 11.2% of the patients, this condition occurred in combination with other congenital pathologies. It is concluded that the diagnosis of congenital stridor is an indication for laryngeal endoscopy regardless of the children's age starting from the first day of life. Meeting this recommendation allows the cause of stridor to be established and the treatment strategy to be developed on an individual basis.

Algorithms for difficult airway management: a review

Difficult airway management and maintenance of oxygenation remain the two most challenging tasks for anesthetists, while also being controversial items in terms of clinically based-evidence to support relevant guidelines in the literature. Nevertheless, different expert groups and scientific societies from several countries have published guidelines dedicated to the management of difficult airways. These documents have been demonstrated to be useful in reducing airway management related critical accidents, despite their limited use in litigations and legal issues. The aim of this review is to compare different airway management guidelines published by the United States, United Kingdom, France, Italy, Germany, and Canada while trying to elucidate the main differences, weaknesses, and strengths for identifying critical concepts in the management of difficult airways.

Anterior Vocal Commissure Invasion in Laryngeal Carcinoma Diagnosis

BACKGROUND

Laryngeal carcinoma involving anterior vocal commissure (AVC) represents a great challenge for staging and treatment.

OBJECTIVES

To compare laryngoscopy and computed tomography (CT) scan efficiency in staging tumors extending to the AVC. We also analyzed the helicoidal axial CT scan accuracy in recognizing this larynx subregion invasion.

MATERIAL AND METHODS

Fifty-two glottic and supraglottic laryngeal squamous cell carcinoma patients with tumoral extension to the AVC were prospectively studied from August 2001 to August 2003 at the National Cancer Institute (Rio de Janeiro, Brazil). All patients underwent videolaryngoscopic examination and direct laryngoscopy for lesion extension analysis and biopsy. After AVC helicoidal axial CT scan with sagittal and coronal 1.0 mm thick reconstruction, patients were submitted to surgical treatment. The same pathologist analyzed all surgical specimens.

RESULTS

When compared with pathologic stage, clinical endoscopic classification was correct in 40.38% of cases (40% for T1, 29.41% for T2, 46.43% for T3, and 50% in T4). Helicoidal axial CT scan accuracy for AVC tumors was 75% (P = .0001), being more important for T2 (62.50%), T3 (73.91%), and T4 (88.24%) lesions. Identification of radiologic signs described as gross radiologic anterior commissure involvement (GRACI) increased radiologic image staging accuracy to over 96%.

CONCLUSIONS

Endoscopic evaluation understaged tumors in all clinical stages but really T1. Helicoidal axial CT scan reformatted to 1.0 mm thick played an important role in correctly staging more advanced AVC laryngeal tumors. Radiologic signs, here identified as GRACI, may be very helpful for tomographic staging and patient treatment.

Laryngeal Cancer in the United States: Changes in Demographics, Patterns of Care, and Survival

BACKGROUND

Survival has decreased among patients with laryngeal cancer during the past 2 decades in the United States. During this same period, there has been an increase in the nonsurgical treatment of laryngeal cancer.

OBJECTIVE

The objectives of this study were to identify trends in the demographics, management, and outcome of laryngeal cancer in the United States and to analyze factors contributing to the decreased survival.

STUDY DESIGN

The authors conducted a retrospective, longitudinal study of laryngeal cancer cases.

METHODS

Review of the National Cancer Data Base (NCDB) revealed 158,426 cases of laryngeal squamous cell carcinoma (excluding verrucous carcinoma) diagnosed between the years 1985 and 2001. Analysis of these case records addressed demographics, management, and survival for cases grouped according to stage, site, and specific TNM classifications.

RESULTS

This review of data from the NCDB analysis confirms the previously identified trend toward decreasing survival among patients with laryngeal cancer from the mid-1980s to mid-1990s. Patterns of initial management across this same period indicated an increase in the use of chemoradiation with a decrease in the use of surgery despite an increase in the use of endoscopic resection. The most notable decline in the 5-year relative survival between the 1985 to 1990 period and the 1994 to 1996 period occurred among advanced-stage glottic cancer, early-stage supraglottic cancers, and supraglottic cancers classified as T3N0M0. Initial treatment of T3N0M0 laryngeal cancer (all sites) in the 1994 to 1996 period resulted in poor 5-year relative survival for those receiving either chemoradiation (59.2%) or irradiation alone (42.7%) when compared with that of patients after surgery with irradiation (65.2%) and surgery alone (63.3%). In contrast, identical 5-year relative survival (65.6%) rates were observed during this same period for the subset of T3N0M0 glottic cancers initially treated with either chemoradiation or surgery with irradiation.

CONCLUSIONS

The decreased survival recorded for patients with laryngeal cancer in the mid-1990s may be related to changes in patterns of management. Future studies are warranted to further evaluate these associations.

[Endoscopic adenotomy--clinical assessment of value and safety--an own experience]

High number of performed adenotomies inclines ENT surgeons to introduce more and more satisfying concerning safety, accuracy and results predictability surgical techniques. The aim of our study was to assess the value and safety of an endoscopic surgical technique. The study was performed on 768 patients aged 7 months - 14 years. Group A (I) consisted of 453 patients on whom adenotomy was performed with use of Beckmann adenotome. Group B (II) consisted of 315 patients operated under endoscope control with the use of Jurasz forceps. An endoscopic technique gives remarkable decrease of intraoperative blood loss and eliminates post op bleedings, what increases patients safety. Low aggressiveness of an endoscopic technique compared to classic decreases incidents of undesirable post adenotomy signs and symptoms. In authors opinion, the results obtained during study, definitely prove the superiority of endoscopic technique--it is worth of introducing into daily surgical practice.

Inter-observer agreement of tests used for prediction of difficult laryngoscopy/tracheal intubation

BACKGROUND

Guidelines recommend pre-operative airway evaluation for the prediction of airway management difficulties. Combining tests for evaluation increases the accuracy of the assessment. One model including seven parameters transformed into a simplified airway risk index (SARI) has been proven to be valid. We determined the inter-observer agreement of the specific test combinations included in SARI as well as of the total score.

METHODS

Four observers assessed 136 patients, 120 without and 16 with a difficult airway history. Two residents and two specialists in anaesthesia performed the airway assessment consisting of the measurement of the mouth opening, the thyromental distance (TMD), the ability to protrude the mandible and an evaluation of the Mallampati class and head and neck mobility. Body weight was also recorded. Inter-observer agreement between specialists and residents, separately, was analysed using kappa statistics and Spearman's correlation analysis and the limits of agreement were evaluated using the 95% confidence interval. The agreement between pairs of assessors was also evaluated.

RESULTS

The inter-observer agreement was good to excellent for both specialists and residents when measuring mouth opening (Spearman's correlation coefficient R=0.88-0.97) and the horizontal distance between the upper and lower incisors during jaw protrusion (R=0.56-0.97). The Mallampati classification assessment demonstrated satisfactory to complete inter-observer agreement (kappa=0.41-1). The assessment of TMD and neck mobility showed considerable discrepancies between observers.

CONCLUSIONS

We demonstrated good inter-observer agreement using three tests from SARI and recommend the Mallampati classification, mouth opening and ability of jaw protrusion for pre-operative airway evaluation. A simplification of the assessment of TMD and neck mobility is warranted.

[Incidence of inappropriate cases for training of emergency medical technicians in endotracheal intubation]

BACKGROUND

Before emergency medical technicians are licensed to perform prehospital endotracheal intubation, they must undergo training in the operating room setting. We investigated the incidence of cases of difficult intubation classified as Cormack & Lehane grade III or IV, because such cases are considered inappropriate for training emergency medical technicians.

METHODS

We examined anesthesia records between March 2002 and April 2003, retrospectively. The survey included 585 adult surgical patients with ASA physical status I or II requiring general endotracheal anesthesia.

RESULTS

Five anesthesiologists and three doctors from the surgical department performed laryngoscopy during this period. In initial laryngoscopy with a Macintosh blade, the view of larynx was grade I in 436, grade II in 98, grade III in 27 and grade IV in 24 patients. In 68 patients, application of cricoid pressure led to improvement of laryngoscopy grade. The use of McCoy blade was necessary for intubation in 16 patients. Out of 51 patients classified as difficult intubation grade III or IV, 35 were originally not expected to be difficult cases.

CONCLUSIONS

Patients with grade I or II view of larynx with a Macintosh blade was only 91%. In order to prepare for unexpected case of difficult intubation, it is necessary to take various measures such as having instructors perform laryngoscopy.

Cricoid Pressure Does Not Increase the Rate of Failed Intubation by Direct Laryngoscopy in Adults

Background

Cricoid pressure (CP) is applied during induction of anesthesia to prevent regurgitation of gastric content and pulmonary aspiration. However, it has been suggested that CP makes tracheal intubation more difficult. This double-blind randomized study evaluated the effect of CP on orotracheal intubation by direct laryngoscopy in adults.

Methods

Seven hundred adult patients undergoing general anesthesia for elective surgery were randomly assigned to have a standardized CP (n = 344) or a sham CP (n = 356) during laryngoscopy and intubation. After anesthesia induction and complete muscle relaxation, a 30-s period was allowed to complete intubation with a Macintosh No. 3 laryngoscope blade. The primary endpoint was the rate of failed intubation at 30 s. The secondary endpoints included the intubation time, the Cormack and Lehane grade of laryngoscopic view, and the Intubation Difficulty Scale score.

Results

Groups were similar for demographic data and risk factors for difficult intubation. The rates of failed intubation at 30 s were comparable for the two groups: 15 of 344 (4.4%) and 13 of 356 (3.7%) in the CP and sham CP groups, respectively (P = 0.70). The grades of laryngoscopic view and the Intubation Difficulty Scale score were also comparable. Median intubation time was slightly longer in the CP group than in the sham CP group (11.3 and 10.4 s, respectively, P = 0.001).

Conclusions

CP applied by trained personnel does not increase the rate of failed intubation. Hence CP should not be avoided for fear of increasing the difficulty of intubation when its use is indicated.

Clinical Outcome of Perioperative Airway and Ventilatory Management in Children Undergoing Craniofacial Surgery

Data on the management of perioperative airway and ventilatory support in children undergoing craniofacial surgery are limited. The purpose of this study was to review the authors' experience with airway management and ventilatory support during the perioperative period in children undergoing craniofacial surgery. Ninety-five consecutive children underwent 99 craniofacial procedures from July 1, 1999, through June 30, 2002. Direct laryngoscopy was successfully used to establish an airway in 86 (86.8%) cases, whereas 13 (13.1%) cases required the use of fiberoptic bronchoscopy to establish an airway before surgery. The oral route was used in 82 (83%) cases, and the nasal route was used in 17 (17%) cases. Length of anesthesia was 330 +/- 160 minutes, and the actual surgical time was 246 +/- 151 minutes. The volume of crystalloids infused during surgery was 87 +/- 78 mL/kg body weight (BW), and the volume of packed red blood cells infused during surgery was 10 +/- 14 mL/kg BW (range, 0-60 mL/kg BW). Tracheal extubation was successfully accomplished in the postanesthesia recovery unit (PACU) in 57 (58%) patients, whereas 42 patients were admitted to the pediatric intensive care unit (PICU) and received mechanical ventilation for 10 +/- 9 hours (range, 1-60 hours). Of these, 37 (37%) were extubated in the PICU, whereas 5 patients were extubated in the operating room with the craniofacial surgeon in attendance in the event an emergency tracheostomy was needed. However, none of these patients required tracheostomy to maintain a secure airway. Three patients required reintubation after the first attempt at tracheal extubation in the PICU. All three of those patients subsequently were extubated without the need for tracheostomy. The length of tracheal intubation and mechanical ventilation was longer (24 +/- 13 hours versus 8.6 +/- 7 hours, P < 0.001) in patients who required bronchoscopic intubation than in those who were intubated using direct laryngoscopy. The length of hospital stay, although clinically relevant, did not reach statistical significance between the two groups (5 +/- 7 days versus 3.7 +/- 2.7 days, P = 0.5). A positive correlation was observed between the duration of tracheal intubation and mechanical ventilation and the following perioperative factors: anesthesia time (rho = 0.6, P < 0.01), surgical time (rho = 0.55, P < 0.01), volume of crystalloids (rho = 0.5, P < 0.01), and the volume of packed red blood cells infused (rho = 0.55, P < 0.01) during surgery. No episodes of cardiorespiratory arrest or death occurred in any of the patients. This study demonstrates that when performing complex craniofacial procedures in children, a thorough evaluation of the airway before surgery and continuous communication between specialists during the perioperative period is imperative for a successful outcome. Furthermore, most pediatric patients who require mechanical ventilation during the postoperative period do so for a short period of time following surgery.

Rapid sequence intubation of trauma patients in Scotland

BACKGROUND

Endotracheal intubation remains the gold standard for trauma airway management. Rapid sequence intubation (RSI) has traditionally been performed by anesthesiologists but increasingly, emergency physicians are also undertaking RSI. We aimed to compare success and complication rates for trauma intubations for the two specialties.

METHODS

Two year, prospective multi-center descriptive study of trauma RSI in seven Scottish urban emergency departments.

RESULTS

439 trauma patients were identified, including 233 RSIs. Patients intubated by emergency physicians had a higher median ISS (p < 0.001) and lower median RTS (p < 0.001) compared with anesthesiologists. For RSI, anesthesiologists had more grade I & II views at laryngoscopy (p = 0.051) and more successful first attempt intubations (p = 0.034) but there was no difference in the number of patients suffering complications (emergency physicians 10.0%, anesthesiologists 10.6%).

CONCLUSION

There is no significant difference in complication rates for trauma RSI between emergency physicians and anesthesiologists in Scottish urban centers. A collaborative approach to the critical trauma airway is vital. Emergency physicians should consult with senior anesthesiologists before RSI when intubation is predicted to be difficult.

Alternating day emergency medicine and anesthesia resident responsibility for management of the trauma airway

STUDY OBJECTIVE

We compare laryngoscopy performance and overall intubation success in trauma airways when primary airway management alternated between emergency medicine and anesthesia residents on an every-other-day basis.

METHODS

Data on all trauma intubations during approximately 3 years were prospectively collected. Primary airway management was assigned to emergency department (ED) residents on even days and anesthesia residents on odd days. Emergency medicine residents intubated patients who arrived without notification or who needed immediate intubation before anesthesia arrived. The study was conducted in an inner-city, Level I trauma center with approximately 50,000 ED patients and 1,800 major trauma cases a year. Main outcomes were success or failure at laryngoscopy and the number of laryngoscopy attempts needed for intubation.

RESULTS

Six hundred fifty-eight trauma patients were intubated during the study period. Laryngoscopy was successful in 654 of 656 cases. Two (0.3%) patients underwent cricothyrotomy after failed laryngoscopy, and 2 (0.3%) patients had awake nasal intubation without laryngoscopy. The specific number of laryngoscopy attempts was unknown in 6 cases (3 from each service), resulting in 650 cases for laryngoscopy performance analysis. Overall, 87% of patients were intubated on first attempt, and 3 or more attempts occurred in 2.9% of patients. Laryngoscopy performance by service (broken down by 1, 2, and >or=3 attempts) was as follows: emergency medicine 86.4%, 11%, and 2.6% versus anesthesia 89.7%, 6.7%, and 3.6%. Analysis by service was done by using Wilcoxon Mann-Whitney testing (P=.225).

CONCLUSION

There were no differences in laryngoscopy performance and intubation success in trauma airways managed on an every-other-day basis by emergency medicine versus anesthesia residents.

[Diagnostic correlation between indirect laryngoscopy, fibro-laryngoscopy and microlaryngoscopy with the anatomopathological results]

We have studied 265 patients with an organical lesion of the larynx, using three different laryngoscopical methods: Indirect laryngoscopy, fibrolaryngoscopy and microlaryngoscopy. We have compared the correlation between each one and the anatomopatological diagnosis, concluding that microlaryngoscopy has the best correlation, better than the fibrolaryngoscopy and this one better than indirect laryngoscopy.

Fiberoptic nasopharyngolaryngoscopy for airway monitoring after obstructive sleep apnea surgery

PURPOSE

This study evaluated the upper airway characteristics in the early postoperative period after reconstructive surgery for obstructive sleep apnea (OSA).

METHODS

During a 24-month period, the upper airway of patients who underwent uvulopalatopharyngoplasty (UPPP) with genioglossus advancement (GA) or hyoid myotomy (HM) or maxillomandibular advancement (MMA) were evaluated with fiberoptic nasopharyngolaryngoscopy (NPG) preoperatively and 24 to 72 hours postoperatively.

RESULTS

NPG was performed on 271 patients. One hundred seventy-three patients had UPPP with GA or HM, and the remainder had MMA. All of the patients who underwent UPPP with GA or HM were found to have varying degrees of soft tissue edema involving the soft palate and the tongue base. The patients who underwent tonsillectomies and UPPP with GA or HM had greater soft palate/pharyngeal wall edema. In contrast, patients who underwent MMA had minimal edema involving the soft palate and the base of tongue, but diffuse lateral pharyngeal wall edema throughout the upper airway was identified. Eighteen of the MMA patients had ecchymosis and edema involving the pyriform sinus and aryepiglottic fold; 4 of these patients also had a hypopharyngeal hematoma involving the pyriform sinus, aryepiglottic fold, arytenoid, and false vocal cord, which partially obstructed the airway. These 4 patients were closely monitored for 1 to 2 additional days, and all were discharged without problems. None of the patients in the study had postoperative airway obstruction.

CONCLUSION

NPG may be useful in postoperative airway monitoring and assist in discharge planning after upper airway reconstruction in the OSA patients.

Difficult intubation in acromegalic patients: incidence and predictability

BACKGROUND

Previous studies have suggested that the incidence of difficult intubation in acromegalic patients is higher than in normal patients. However, these studies were retrospective and did not include preoperative assessment of the airways. The aims of this study were to determine the incidence of difficult intubation and to assess the usefulness of preoperative tests in predicting difficult laryngoscopy.

METHODS

One hundred twenty-eight consenting acromegalic patients requiring general anesthesia and tracheal intubation were studied. Preoperatively, Mallampati classification, thyromental distance, and head and neck movement were determined in each patient. After induction of anesthesia and muscle paralysis, laryngoscopic grade was assessed during direct laryngoscopy; Cormack and Lehane grade III or IV were classified as difficult. The association of individual airway assessment with laryngeal view was evaluated using the Fisher exact test. Predictors of difficult laryngoscopy were evaluated by calculating their sensitivity and specificity.

RESULTS

Laryngoscopy was difficult (grade III) in 33 of 128 patients (26%). Application of external laryngeal pressure improved laryngeal visualization to grade II in 20 of these 33 patients. In the remaining 13 patients (10%), intubation was difficult (more than two attempts, blade change, use of gum-elastic bougie). Mallampati classes 3 and 4 were significantly related to laryngoscopy grade III (Fisher exact test, P = 0.001).

CONCLUSIONS

The incidence of difficult laryngoscopy and intubation in acromegalic patients is higher than in normal patients. Preoperative Mallampati scores of 3 and 4 were of value in predicting difficult laryngoscopy. Nevertheless, even this test will miss a significant number of patients with a difficult airway.

[Rigid endoscopy and laryngo-tracheo-bronchial foreign bodies in children: observations apropos of 200 endoscopies conducted in a tropical setting]

Between 1986 and 1998, 200 rigid bronchoscopic procedures under general anesthesia were carried out at the Principal Hospital in Dakar, Senegal for foreign body extraction from the distal airways of 194 children. For the study period, the incidence of this accident was 3.7 p. 1000. Sixty-three percent of patients were male and 77 p. 100 were under 4 years of age. Most patients (69 p. 100) were examined within 48 hours after the accident. Examination of clinical records showed that aspiration was mentioned during anamnesis in only 56 p. 100 of cases. Persistent coughing (80 p. 100) and mild dyspnea (70 p. 100) were the most common symptoms. Auscultation of the lungs was negative in 25 p. 100 of cases and anterior x-ray of the neck and chest were normal or poorly informative in 59 p. 100. In 154 of the 200 procedures, extraction of the foreign body was successful from the trachea in 35 p. 100 of cases, the larynx in 13 p. 100, the right main stem bronchus in 31 p. 100 and the left main stem bronchus in 21 p. 100. In the remaining 46 cases, extraction was unsuccessful. The most frequent foreign body was a peanut. No deaths occurred in this series but cardiac arrest was observed in 6 patients during or immediately after endoscopy. This experience confirms the indication for immediate rigid bronchoscopy in cases involving aspiration or persistent respiratory symptoms. The high incidence of this accident suggests that information campaigns should be undertaken in health care facilities, households, and schools.

Efficacy of fiberoptic laryngoscopy in the diagnosis of inhalation injuries

BACKGROUND

A significant proportion of burn patients with inhalation injuries incur difficulties with airway protection, dysphagia, and aspiration. In assessing the need for intubation in burn patients, the efficacy of fiberoptic laryngoscopy was compared with clinical findings and the findings of diagnostic tests, such as arterial blood gas analysis, measurement of carboxyhemoglobin levels, pulmonary function tests, and radiography of the lateral aspect of the neck.

OBJECTIVE

To determine if these patients were at risk for aspiration or dysphagia, barium-enhanced fluoroscopic swallowing studies were performed.

DESIGN

Prospective study.

SETTINGS

Burn intensive care unit in an academic tertiary referral center.

MAIN OUTCOME MEASURES

Need for endotracheal intubation and potential for aspiration.

RESULTS

Six (55%) of 11 patients had clinical findings and symptoms that indicated, under traditional criteria, endotracheal intubation for airway protection. Visualization of the upper airway with fiberoptic laryngoscopy obviated the need for endotracheal intubation in all 11 patients. These patients also failed to evidence an increased risk of aspiration or other swallowing dysfunction.

CONCLUSIONS

In comparison with other diagnostic criteria, fiberoptic laryngoscopy allows differentiation of those patients with inhalation injuries who, while at risk for upper airway obstruction, do not require intubation. These patients may be safely observed in a monitored setting with serial fiberoptic examinations, thus avoiding the possible complications associated with intubation of an airway with a compromised mucosalized surface. In these patients, swallowing abnormalities do not manifest.

The quick look airway classification. A useful tool in predicting the difficult out-of-hospital intubation: experience in an air medical transport program

The unpredictable nature of the out-of-hospital care environment poses unique challenges for active airway management techniques. This descriptive study was conducted in the helicopter air medical transport (AMT) environment for a period of 32 months to determine whether initial direct airway visualization classification may provide a useful tool to predict the difficulty of intubation. Data extracted from documented oral intubation attempts included initial airway visualization grade, number of attempts, final airway management method, and procedural complications. Oral intubation was attempted on 429 patients. Initial airway visualization grades were found with the following frequency for grades I through IV: 65.6%, 21.5%, 8.6%, and 5.4%, respectively. Similarly, the average number of attempts was 1.34, 1.65, 1.97, and 2.39, respectively. The serious complication rate was 24%, 46%, 62%, and 65%, respectively. A statistically significant correlation (Spearman's rho) was found between increasing grade and both the number of intubation attempts (0.52) and the number of complications (0.45). Initial visualization classification may serve as a useful indicator in the out-of-hospital environment to help anticipate the difficulty of intubation and the need for early alternative airway management strategies. In this program, such classification is used to monitor airway management skills.

[Difficult intubation in otorhinolaryngologic laser surgery. Is there a predictive parameter?]

In the planning of laser surgery for ENT operations, the specialist is often consulted by the anesthesiologist to predict possible intubation problems. Intubation problems in such operations can occur frequently due to the pathological findings present in the upper aerodigestive tract and the different constructions of laser-resistant endotracheal tubes. The aim of this study was to determine if a known predictive parameter could have a sufficient sensitivity and specificity to reliably predict possible intubation problems for ENT-related laser surgery. In a prospective study, 91 patients were included and the Mallampati-score modified by Samsoon and Young was analyzed and compared to a score describing the actual conditions of intubation. The results showed a significant correlation (p < 0.05, Chi-Square test). However, the specificity was only 72% and the sensitivity of 60% was too low to be of practical use. The results were independent of the endotracheal tube used. Although use of the laser for ENT operations provides a special situation for the anesthesiologist, there is still no system that is sensitive and specific enough to be of practical use. This problem is demonstrated in a literature review.

Elective tracheal intubation in cervical spine injuries

Patients presenting for surgical stabilisation of an unstable cervical spine are at risk of sustaining a further iatrogenic spinal cord injury during intubation of the trachea. Controversy exists regarding the optimal anaesthetic technique for securing the airway. We reviewed the techniques employed for intubating the trachea in our hospital over a five year period. Tracheal intubation was achieved using two different techniques: awake fibre-optic intubation with local anaesthesia, and general anaesthesia via the intravenous or inhalational route with neuromuscular blockade. Forty five patients were included. 16 patients demonstrated a pre-operative neurological deficit. Awake fibre-optic intubation was used in 27 cases, general anaesthesia was employed via the intravenous route in 17 cases and the inhalational route in 1 case. Weighted traction was employed in all cases to immobilize the cervical spine during intubation. There was no new neurological sequelae with any of these techniques. Our study suggests that there is no optimal anaesthetic technique for intubating the trachea in patients with cervical spine injuries and it is noteworthy that in line traction was used in every case.

Observer agreement about laryngoscopic assessment of papilloma

BACKGROUND

Observer bias may confound the assessment of therapies utilized for recurrent respiratory papilloma, a recidivistic fluctuating disease. Any convincing change in a patient's disease must exceed the imprecision of the measuring system.

MATERIALS AND METHODS

Videotapes of ten children, who had airway endoscopy for care of laryngeal papilloma, were edited. The videotapes were independently reviewed by six otolaryngologists, of whom five repeated their assessments 5 to 20 weeks later. The 'reference standard' was the operating surgeon's categorization of his patient's videotape. Agreement was calculated by the kappa statistic, the observed proportions of positive and negative agreement, and the proportion categorized as exact opposites, for each of twelve anatomic sites.

RESULTS

Moderate agreement was found for both (a) the operative findings versus the later-determined 'reference standard', and (b) the 'reference standard' versus categorizations by other otolaryngologists. Intra-observer agreements were better than inter-observer agreements. Agreement as to whether or not papilloma involved each of twelve sites was within about 20% for the five pediatric otolaryngologists vs the 'reference standard', and within about 10% for the same reviewer.

CONCLUSION

Videotapes may add objectivity to the assessment of laryngeal papilloma. For changes to be considered significant, an observer should identify a 10% change in the number of sites involved, or a 30% change in the extent of overall airway obstruction. For different observers, changes would have to be even greater to be meaningful.

Instability of voice in adolescence: pathologic condition or normal developmental variation?

OBJECTIVE

Pediatricians often send adolescents with dysphonia to the otorhinolaryngologist's office to find the reason for their hoarseness. The aim of this study was to identify the main characteristics of adolescent voice and to determine which characteristic (variable of voice analysis) can distinguish normal variations of voice development from pathologic disorders.

STUDY DESIGN

On the basis of history, indirect laryngoscopy, and stroboscopy, 51 adolescents (22 boys, 29 girls) from age 10 to 17 years were divided into four subgroups: candidates for singing lessons without voice problems, subjects with mutation voice disorders, subjects with functional dysphonia, and subjects with vocal cord nodules. Voice analysis by Multi-Dimensional Voice Program (Kay Elemetrics) evaluated the fundamental frequency, the variability of pitch and amplitude (loudness), and the presence of noise in the analyzed voice sample of each of the subjects. Data were analyzed with the SPSS+/PC Statistical Program.

RESULTS

All mean values of variables that describe variability of pitch and amplitude were abnormal in boys and in girls, with greater abnormality among boys. The variability of loudness and specifically the variability of pitch were abnormal in a majority of subjects. A significant negative correlation between age and fundamental frequency was stated in boys only and between age and variability of amplitude in girls only. Variables that express variability of pitch and amplitude correlated positively between themselves. No significant differences were found between the first subgroup (candidates for singing lessons), which represented a normal population, and the other three subgroups (subjects with mutational disorders, functional dysphonia, and vocal cord nodules). In addition, no significant differences were found between the first three subgroups (subjects without voice problems and subjects with functional voice disorders) and the fourth subgroup (subjects with vocal cord nodules: organic lesion of laryngeal mucosa).

CONCLUSIONS

According to this study, the main characteristic of adolescent voice is the instability of amplitude (loudness) and specifically the instability of pitch. Female voices appear more stable than male voices. No single variable of performed voice analysis can distinguish normal variation of voice development from pathologic disorders. The reason for this instability can be attributed to more gradual adaptation of the afferent and efferent nervous control to the rapid growth of the phonatory, respiratory, and resonatory organs. In the growing speech apparatus, optimal phonatory patterns can be created; therefore adolescence is an ideal period for treatment of functional voice disorders.

Reconsidering a paradigm: the spread of supraglottic carcinoma to the glottis

This study was performed to evaluate the spread of supraglottic carcinoma to the glottic level. Whole organ sections of total laryngectomy specimens from 37 patients with previously untreated supraglottic carcinomas were reviewed retrospectively. Of the 37 specimens, 20 (54%) were noted to have extension of cancer to the glottic level. A significant relationship was noted between glottic extension and abnormal cord motion (P = .0002). A statistically significant trend was noted for the relationship between inferior extension along the supraglottic mucosa and glottic level extension (P < .0001). Contrary to the prevailing model of the spread of supraglottic carcinoma, in which there is a distinct barrier to spread at the ventricle, this analysis of selected supraglottic carcinomas revealed a continuum of spread from the supraglottic to the glottis.

Laryngeal response during forced vital capacity maneuvers in normal adult humans

Previous investigators have reported that transient forced expiration is accompanied by abduction of the vocal cords. To further investigate the laryngeal response during voluntary forced vital capacity maneuvers, intramuscular electromyographic recordings were obtained in 25 normal adult humans from three intrinsic laryngeal muscles: the posterior cricoarytenoid (PCA), a vocal cord abductor, and the thyroarytenoid (TA) and arytenoideus (AR), both vocal cord adductors. All three muscles exhibited sustained activation throughout most of forced expiration from total lung capacity. Forced inspiration from residual volume was associated with a further increase in PCA activity and a marked decrease in adductor muscle activity. To determine the net effect of these electromyographic changes on vocal cord position, simultaneous fiberoptic recordings of vocal cord movement were obtained in five of the subjects. The angle formed by the vocal cords at the anterior commissure was used to assess glottic aperture size. Glottic angle progressively decreased from peak expiratory flow to the end of forced expiration. The angle was 56 +/- 13 degrees (SD) at peak expiratory flow, 34 +/- 4 degrees after forced expiration of 90% of the vital capacity, and 7 +/- 7 degrees at end-expiration. The results indicate that forced expiration is associated with marked activation of not only the PCA but also laryngeal adductor muscles. During forced expiration, the glottis does not decrease below its size during quiet breathing until exhalation of about 75% of forced vital capacity.

The airway: problems and predictions in 18,500 patients

The purpose of this study was to describe methods, risk factors, and outcomes of airway management in all patients (obstetrics excluded) attended by anaesthetists over 27 months. Preoperatively, anaesthetists recorded patient factors and assessed four airway characteristics. Methods of tracheal intubation and ease of direct laryngoscopy following general anaesthesia (easy, awkward, difficult) were noted. Factors predictive of poor outcome and the value of the preoperative airway examination were determined. For 18,205 patients following a direct laryngoscopy, (GA), tracheal intubation was difficult (> 2 laryngoscopies) in 1.8% and awkward (< or = 2 laryngoscopies) in 2.5%. This approach was a failure in 0.3%, and surgery was postponed in 0.05%. However, an alternative approach to direct laryngoscopy, (GA) was the first choice in 353 patients. Risk factors for difficult tracheal intubation included male sex, age 40-59 yr and obesity (P < or = 0.01). For direct laryngoscopy, (GA), airway characteristics predictive of difficult tracheal intubation were decreased mouth opening (relative risk 10.3), shortened thyromental distance (9.7), poor visualization of the hypopharynx (4.5), and limited neck extension (3.2), any two (7.6) and more than two (9.4) (P < 0.01). For 1,856 patients (10.0%) where at least one airway characteristic was abnormal, a direct laryngoscopy, (GA) resulted in 8.3% awkward and 6.0% difficult tracheal intubations. For patients with no abnormal airway characteristics, tracheal intubation was easy in 96.3%. Where tracheal intubation was difficult, 34.3% of patients had one or more abnormal airway characteristics preoperatively. Patients with difficult tracheal intubation had an increased rate of desaturation (< 90%), hypertension (> 200 mm Hg) and dental damage on induction of anaesthesia. It is concluded that difficult tracheal intubations occurred infrequently but were associated with increased morbidity. Patient factors and four physical airway characteristics were useful predictors but limited in identifying all problems.

Pediatric laryngobronchoscopy. 1332 procedures stored in a data base

Laryngobronchoscopy (LBS), using both rigid and flexible bronchoscopes, has become a frequently performed operation in children. A data base was established to enable retrospective evaluation of a large number of LBSs carried out in a pediatric center. Experience with 1332 cases of LBS involving 808 patients over an 8-year period is presented. The main indications for LBS were inspiratory stridor, atelectasis, and suspected foreign body aspiration. Most frequent diagnoses at LBS were bronchopneumonia, intubation trauma, tracheomalacia, laryngomalacia, and foreign body aspiration. Only 25 complications occurred (1.9%) including two cases of xylometazoline intoxication.

Changing patterns of epiglottitis in children

With an increased awareness of appropriate management of childhood epiglottitis, overall morbidity and mortality has decreased. However, some trends have developed over the past several years that are variations on the classic picture. In a series of 42 patients seen from 1977 to 1986, epiglottitis has occurred in a progressively younger population. Thirty-six percent of our patients were found to be less than 2 years old, and 51% were less than 3 years old. Also, the causative organism, Haemophilus influenzae, has been found to be increasingly ampicillin-resistant. The incidence, presentation, management, and outcome of the patients are reviewed, and compared to similar data from other series in the literature.