Consistent Technique Limits Suspension Laryngoscopy Complications

Dental impression silicone putty in transoral laser laryngeal surgery: prevention of oral complications

Objective

To describe a new method to improve the exposure of the surgical field and to protect the oral cavity during transoral laser micro-surgery (TOLMS) of the larynx.

Methods

Dental Impression Silicone Putty (DISP) was employed as an alternative to traditional mouthguards.

Results

DISP mouthguards perfectly fit to each patient, reduce encumbrance in the mouth, and reduce pressure on the teeth; disadvantages are minimal.

Conclusions

Although clinical studies are necessary to demonstrate the efficacy of the method in reducing the incidence of oral complications, DISP mouthguards represent a significant aid for laryngeal exposure.

Quantifying Intubation Forces on Incisors and Tongue Base Across Exposure Difficulty and Experience in a Simulator

OBJECTIVE

Laryngoscopy simulators quantifying forces on critical structures in progressively challenging airways and operator expertise are lacking. We aimed to quantify laryngoscopy forces across expertise and exposure difficulty.

STUDY DESIGN

Prospective observational study Setting: Tertiary care medical center Methods: Force gauges were affixed to a difficult airway mannequin to quantify teeth and tongue forces across increasingly challenging airway exposure. Medical students (n=10), residents (n=11), and otolaryngology staff (n=10) performed direct laryngoscopy using a Miller size 3 laryngoscope with 1) normal neck/jaw mobility, 2) restricted neck extension, 3) restricted jaw opening, and 4) restricted neck/jaw mobility. Incisor and tongue pounds of force (lbf) were continuously measured.

RESULTS

As the difficulty setting increased, forces exerted by the students, residents, and staff on the incisors and tongue base increased (p=0.01). Between normal and maximally restricted settings, force delivered to the incisors increased by 6.95 lbf (standard error (SE) 1.29), 5.93 lbf (SE 0.98), and 5.94 lbf (SE 0.70) for the students, residents, and staff, respectively. At the tongue base, force increased by 0.37 lbf (SE 0.18), 0.46 lbf (SE 0.14), and 0.73 lbf (SE 0.15) for the students, residents, and staff, respectively. Esophageal intubations occurred in 50% of the students, 23% of the residents, and 45% of the otolaryngology staff at maximal difficulty, with none at the easiest setting (p=0.33). Compared to the residents, the staff applied significantly increased pressure on the tongue base during laryngoscopy (p=0.02).

CONCLUSION

Forces exerted on the incisors and tongue base varied across exposure difficulty and expertise levels, suggesting that they may be useful markers for training and competence assessment.

Informed consent for suspension microlaryngoscopy: what should we tell the patient? A consensus statement of the European Laryngological Society

INTRODUCTION

Informed consent for any surgical intervention is necessary, as only well-informed patients can actively participate in the decision-making process about their care, and better understand the likely or potential outcomes of their treatment. No consensus exists on informed consent for suspension microlaryngoscopy (SML).

MATERIALS AND METHODS

Informed consent procedures in nine countries on five continents were studied.

RESULTS

Several risks can be discerned: risks of SML as procedure, anesthesiologic risks of SML, specific risks of phonosurgery, risks of inadequate glottic exposure or unexpected findings, risks of not treating. SML has recognized potential complications, that can be divided in temporary (minor) complications, and lasting (major) complications.

CONCLUSION

SML is a safe procedure with low morbidity, and virtually no mortality. Eleven recommendations are provided.

Comparison of Dental Injury Rates in Perioperative Intubation and Suspension Laryngoscopy for Otolaryngology Procedures

Objective

Direct laryngoscopy is an essential skill during perioperative intubation and otolaryngology procedures. Dental injury is a common complication of direct laryngoscopy. However, the technique and tools used by anesthesiologists, nurse anesthetists, and others during perioperative intubation and by ear, nose, and throat surgeons for their procedures are different. The purpose of this review is to explore the literature for all studies detailing rates of dental injury in each of these settings and to compare them to see if the approaches have a significant difference in rate of dental injury.

Data Sources

PubMed.

Review Methods

A comprehensive search of PubMed was performed through February 2021 with search terms “dental” and “intubation” or “laryngoscopy.” PRISMA guidelines were followed. Studies documenting rates of dental injuries during intubation or during laryngologic procedures were included, and the 2 groups were compared.

Results

Twenty-three studies met inclusion criteria: 17 in the perioperative intubation group and 6 in the suspension laryngoscopy group. There was an increased incidence of dental injury in the perioperative intubation group (4.86%) as compared with the suspension laryngoscopy group (1.70%).

Conclusions

The difference in dental injury rate between the groups could be due to the differences in direct laryngoscopy technique or tools used, the presence vs absence of a dental guard, or a combination of these factors. More studies need to be performed to develop definitive and specific conclusions to recommend changes that prevent dental injury.

Iatrogenic hypoglossal nerve palsy, a rare complication post suspension laryngoscopy

The hypoglossal nerve (CN XII) is a pure motor nerve arising as a paired nerve from its nuclei in the medulla, exiting the skull base via the hypoglossal canal, and descending the neck to innervate the muscles of the tongue. Iatrogenic hypoglossal nerve palsy is uncommon, but cases have been reported, especially after airway management in general anaesthesia and suspension laryngoscopy. We report a case of iatrogenic hypoglossal nerve palsy post-suspension laryngoscopy, which was managed conservatively with full recovery after three months. We discuss the importance of minimal consent for suspension laryngoscopy and possible methods to prevent this uncommon yet unpleasant complication.

Suspension laryngoscopy experiences in a tertiary airway service: A prospective study of 150 procedures

OBJECTIVES

In most cases, suspension laryngoscopy (SL) is efficient, bloodless and with minimal post-procedure discomfort. We aimed to identify predictive patient factors for acceptable surgical views at SL as well as quantify our tertiary airway unit's complication rates.

DESIGN

Prospective cohort study of 150 consecutive microlaryngoscopy procedures involving SL over an 8-month period between November 2019 and July 2020. Patients were assessed preoperatively for pre-existing oral, temporomandibular, dental, pharyngeal or laryngeal pathology, interincisor distance and qualitative gross limitations to neck extension and forward head posture. Intraoperatively, the laryngoscopic view was graded by anaesthetic and surgical teams, and complications were recorded on patient interview in recovery.

SETTING

Tertiary adult airway service for predominantly benign pathology.

RESULTS

Adequate surgical views were obtained in 149/150 procedures. BMI had a weak positive correlation with a more difficult view (r = .22, p = .008) but did not correlate with a statistically significant increase in any complication. There was a weak negative correlation between age and interincisor gap (r = -.20, p = .014), and wider mouth opening correlated very weakly with a lower incidence of sore throat (r = -.19, p = .023). Gross macroglossia showed a significant moderate positive correlation with tongue symptoms (r = .45, p = 1.611 × 10^-8 ).

CONCLUSION

In the context of an experienced airway unit with a high caseload of predominantly benign pathology, SL is very effective and safe with low associated morbidity and no mortality. The most common complication of SL is temporary sore throat and there remain recognised risks of temporary tongue and dental symptoms.

Is it possible that direct rigid laryngoscope-related ischemia-reperfusion injury occurs in the tongue during suspension laryngoscopy as detected by ultrasonography: a prospective controlled study

Background: Tongue-related complications can be seen in suspension laryngoscopy (SL) procedures.Aims/objectives: This study aimed to detect tongue edema associated with the pressure exerted by a rigid direct laryngoscope by measuring the tongue area using ultrasonography (USG) in patients undergoing SL procedures.Material and methods: The study group included 31 patients and the control group consisted of 33 patients. Submental USG examinations of the tongue in the coronal plane were performed. In the study and control groups, the first examination (TA¹) was done immediately after intubation and the second examination (TA²) was done after the surgery procedure but before extubation. The USG results regarding tongue area for both the groups were compared.Results: The study and control groups significantly differed in terms of the postoperative tongue area measurements (TA²), as well as tongue edema (based on the TA² - TA¹) values.Conclusions and significance: Direct rigid laryngoscopes may cause tongue edema in SL procedures which was demonstrated by the USG. This tongue edema can be a result of ischemia-reperfusion injury in the tongue due to the pressure exerted by a direct rigid laryngoscope. This study is the first to demonstrate the possible role of USG examination in determining the side effects of SL procedures on the tongue. Trial Registration ClinicalTrials.gov Identifier: NCT04205253.