Postoperative sore throat: influence of tracheal tube lubrication versus cuff design

The incidence and severity of postoperative sore throat was evaluated in six groups of 20 patients each after elective orthopedic surgery. Groups I to V had tracheal intubation with Portex disposable polyvinylchloride tracheal tubes and group VI had mask anaesthesia. All groups were exposed to heated humidified gases. Tracheal tubes in groups I—III were uncuffed and lubricated with four per cent lidocaine jelly (group I), four per cent lidocaine hydrochloride anaesthetic solution (group II) or normal saline (group III). Patients in group IV had unlubricated tubes with large residual volume cuffs, patients in group V unlubricated tubes with small residual volume cuffs and patients in group VI (mask anaesthesia) had the lowest incidence and severity of postoperative sore throat while those in group I had the highest incidence and most severe postoperative sore throats. Patients in group V had a lower incidence and severity of postoperative sore throat than patients in all other groups, except group VI. Postoperative sore throat was equally common and severe in patients in groups II, III, and IV. The data indicate that, with the use of heated humidified gases, tracheal intubation with either cuffed or uncuffed tubes produces a greater incidence and severity of postoperative sore throat than mask anaesthesia. In addition, our findings suggest that lubrication of tracheal tubes provides no advantage in terms of reducing postoperative sore throat and, depending on the lubricant, can increase the incidence and severity, Finally, our results demonstrate that the tracheal tube causing the least incidence and severity of postoperative sore throat is one with an unlubricated low residual volume cuff.     

Postoperative pulmonary complications in older patients undergoing elective surgery with a supraglottic airway device or tracheal intubation

The two most commonly used airway management techniques during general anaesthesia are supraglottic airway devices and tracheal tubes. In older patients undergoing elective non-cardiothoracic surgery under general anaesthesia with positive pressure ventilation, we hypothesised that a composite measure of in-hospital postoperative pulmonary complications would be less frequent when a supraglottic airway device was used compared with a tracheal tube. We studied patients aged ≥ 70 years in 17 clinical centres. Patients were allocated randomly to airway management with a supraglottic airway device or a tracheal tube. Between August 2016 and April 2020, 2900 patients were studied, of whom 2751 were included in the primary analysis (1387 with supraglottic airway device and 1364 with a tracheal tube). Pre-operatively, 2431 (88.4%) patients were estimated to have a postoperative pulmonary complication risk index of 1–2. Postoperative pulmonary complications, mostly coughing, occurred in 270 of 1387 patients (19.5%) allocated to a supraglottic airway device and 342 of 1364 patients (25.1%) assigned to a tracheal tube (absolute difference −5.6% (95%CI −8.7 to −2.5), risk ratio 0.78 (95%CI 0.67–0.89); p < 0.001). Among otherwise healthy older patients undergoing elective surgery under general anaesthesia with intra-operative positive pressure ventilation of their lungs, there were fewer postoperative pulmonary complications when the airway was managed with a supraglottic airway device compared with a tracheal tube.     

Tracheal tube size in adults undergoing elective surgery – a narrative review

Tracheal tubes are routinely used in adults undergoing elective surgery. The size of the tracheal tube, defined by its internal diameter, is often generically selected according to sex, with 7–7.5 mm and 8–8.5 mm tubes recommended in women and men, respectively. Tracheal diameter in adults is highly variable, being narrowest at the subglottis, and is affected by height and sex. The outer diameter of routinely used tracheal tubes may exceed these dimensions, traumatise the airway and increase the risk of postoperative sore throat and hoarseness. These complications disproportionately affect women and may be mitigated by using smaller tracheal tubes (6–6.5 mm). Patient safety concerns about using small tracheal tubes are based on critical care populations undergoing prolonged periods of tracheal intubation and not patients undergoing elective surgery. The internal diameter of the tube corresponds to its clinical utility. Tracheal tubes as small as 6.0 mm will accommodate routinely used intubation aids, suction devices and slim-line fibreoptic bronchoscopes. Positive pressure ventilation may be performed without increasing the risk of ventilator-induced lung injury or air trapping, even when high minute volumes are required. There is also no demonstrable increased risk of aspiration or cuff pressure damage when using smaller tracheal tubes. Small tracheal tubes may not be safe in all patients, such as those with high secretion loads and airflow limitation. A balanced view of risks and benefits should be taken appropriate to the clinical context, to select the smallest tracheal tube that permits safe peri-operative management.     

Tracheal intubation and sore throat: a mechanical explanation

Although tracheal intubation remains a valuable tool, it may result in pressure trauma and sore throat. The evidence for an association between these sequelae is not conclusive and sore throat may be caused at the time of intubation. This hypothesis was tested in a mechanical model and the results from tracheal intubation compared with those from insertion of a laryngeal mask airway, which is associated with a lower incidence of sore throat. Use of the model suggests that the tracheal tube and laryngeal mask airway impinge on the pharyngeal wall in different manners and involve different mechanisms for their conformation to the upper airway, but that in a static situation, the forces exerted on the pharyngeal wall are low with both devices. It also suggests that the incidence of sore throat should be lower for softer and smaller tracheal tubes and that the standard 'Magill' curve (radius of curvature 140 +/- 20 mm) is about optimum for the average airway.     

Postoperative sore throat related to tracheal tube cuff design

Recent reports of the incidence of postoperative sore throat following anaesthesia with trachéal intubation have claimed that low volume high pressure cuffs are preferable to those with high volume and low pressure. In this study similar methods were used for evaluating postoperative sore throat. Randomly selected trachéal tubes were used in 56 patients undergoing elective abdominal surgery, followed by direct questioning about sore throat on the first postoperative day. The incidence of postoperative sore throat was 41 per cent with high volume low pressure cuffed tubes and 55 per cent with low volume high pressure cuffed tubes. This difference is not statistically significant, but the tendency of the results is contradictory to those published earlier. The incidence of postoperative sore throat varies greatly if direct or indirect questioning is used and also varies between studies using the same method of questioning. Therefore the validity of this method for evaluating the influence of cuff design must be questioned. Postoperative sore throat is a symptom caused by many factors, such as the intubation procedure and the use of stylets or lubricants. The incidence of postoperative sore throat does not necessarily reflect damage caused by the trachéal tube cuff.     

Quality improvement in anesthetic practice--incidence of sore throat after using small tracheal tube

BACKGROUND AND OBJECTIVE: Sore throat following surgery is common and is due to multitude of factors. The highest incidence of sore throat tends to occur in patients who have undergone tracheal intubation. Between 14.4% to 50% of intubated patients complain of sore throat and hoarseness in the immediate postoperative period, 3% of them are still hoarse after a week. This contributes to higher incidence of postoperative morbidity and patient dissatisfaction of the service. A prospective study was conducted to demonstrate the incidence of hoarseness and sore throat following the use of small tracheal tubes. METHODS: Adult patients, 16 years old and above, presented for tonsillectomy, nasal surgery and/or for functional endoscopic sinus surgery (FESS) were included in the study. Patients who had signs of, common cold were excluded from the study. Size 7-7.5 mm cuffed tracheal tube was used in males and size 6-6.5 mm in females. Patients were asked during 24 hours postoperatively about the presence of hoarseness of voice and of their satisfaction of the service. RESULTS: There were 1618 patients 883 males and 735 females, ages: 16-62 yrs included in the study between February 2000 and end of May 2003. 189 (11.7%) developed postoperative hoarseness of voice and 1429 (88.3%) did not have hoarseness or sore throat (P = 0.0001). Patient satisfaction was 95%. CONCLUSIONS: The use of small tube in intubating the trachea, together with other measures such as lubricating the tube with water soluble jelly, careful airway instrumentation, intubation only when patient was fully relaxed, careful suctioning technique, and extubation when the tracheal tube cuff was fully deflated, have dramatic effects on minimizing the incidence of postoperative hoarseness and sore throat. Accordingly, patient satisfaction has been reported to be high.     

Postoperative sore throat: cause, prevention and treatment

Sore throat is a common postoperative complaint, occurring most often following tracheal intubation. Factors such as tracheal-tube size and cuff design have been shown to be important causative factors. Routine tracheal intubation for elective surgical procedures can result in pathological changes, trauma and nerve damage which may also account for postoperative throat symptoms. Sore throat following the use of a laryngeal mask appears to be related to the technique of insertion but the contribution of intracuff pressure remains to be clarified. It would appear, however, that high intracuff pressure is associated with nerve palsies due to neuropraxia and nerve compression. Careful insertion techniques for both the tracheal tube and laryngeal mask are of paramount importance in the prevention of airway trauma and postoperative sore throat.     

Sore throat after endotracheal intubation.

Nitrous oxide can diffuse into the cuff of an endotracheal tube during tracheal intubation, and the cuff pressure against the tracheal wall may cause mucosal damage. An endotracheal tube has been developed (Brandt Anesthesia Tube) that effectively limits nitrous oxide-related intracuff pressure increases. We determined whether the incidence of postoperative sore throat could be reduced by using this tube. Forty-eight female patients, 18-50 yr of age, were included in the study. Endotracheal intubation was performed with either a Brandt Anesthesia Tube or a Mallinckrodt endotracheal tube. All patients were interviewed postoperatively after 20-30 h by individuals who did not know which tube was used. In the Mallinckrodt group, 12 of 20 patients had a sore throat and 10 patients had intracuff pressures greater than 25 mm Hg. Only 3 of 20 patients in the Brandt group had a sore throat. We found that the incidence of sore throats after intubation could be significantly reduced by using the Brandt Anesthesia Tube (P less than 0.005).     

Pharyngo-laryngeal discomfort after breast surgery: comparison between orotracheal intubation and laryngeal mask

Sore throat and dysphonia are a significant source of postoperative discomfort for patients scheduled for breast surgery who have been intubated for general anaesthesia. The aim of this study was to compare the incidence of postoperative pharyngo-laryngeal pain and dysphonia in the use of the laryngeal mask airway (LMA) or tracheal intubation in these patients. In a prospective, double-blind, randomised clinical trial we studied 53 women undergoing elective breast surgery to test the hypothesis that the use of the LMA could reduce the incidence of pharyngo-laryngeal morbidity compared with tracheal intubation. Postoperative sore throat and hoarseness were assessed at 6 and 24h by a standardised interview. The incidence of postoperative sore throat was significantly higher in the case of tracheal intubation at 6h (74% vs. 27%, p=0.0003) and at 24h (27% vs. 0%, p=0.004). The incidence of hoarseness was significantly higher in the tracheal intubation group than in the LMA group at 6h after surgery (40% vs. 15%, p=0.04), but not at 24h. Compared with tracheal intubation, the use of the LMA is associated with a lower incidence of postoperative sore throat and hoarseness and may contribute for improving patient comfort after breast surgery.     

Postoperative hoarseness and sore throat after tracheal intubation: effect of a low intracuff pressure of endotracheal tube and the usefulness of cuff pressure indicator]

Many clinical reports have described postoperative hoarseness and sore throat after general anesthesia. In most cases, these symptoms were attributed to high pressure of the endotracheal tube cuff. The recommended cuff pressure is less than 25 mmHg, as excessive pressure produces ischemia of the tracheal mucosa. However, within the safe pressure range, postoperative hoarseness and sore throat are still often observed. In this study, one hundred and ninety patients of ASA classes I or II were allocated randomly to two groups, low cuff pressure group (< 15 mmHg) or high cuff pressure group (15-25 mmHg), using continuous monitoring with a cuff pressure gauge. We investigated the incidence of postoperative hoarseness and sore throat at 24 hours after intubation and on the seventh postoperative day. The incidence of postoperative hoarseness and sore throat was significantly decreased in the low pressure group at 24 hours after intubation as compared with the high pressure group, but there was no significant difference between the two groups on the seventh postoperative day. These results suggest that keeping the cuff pressure under 15 mmHg can prevent postoperative hoarseness or sore throat at 24 hours after intubation, and that a cuff pressure gauge is thought to be one of the indispensable monitors during anesthesia.     

气管导管套囊高压的影响因素及并发症的预防

气管插管是通过建立人工气道抢救和治疗危重患者的重要措施。气管导管套囊压力的监测是人工气道管理的重要组成部分。多种因素均可导致套囊压力增高,引起咽痛、咳嗽、气道炎症和气道狭窄等多种并发症,对患者术后恢复产生较多不良影响。为减少套囊高压相关并发症的发生,增强麻醉科医师套囊压监控管理意识,本文将从影响套囊压力变化的因素和套囊高压所致并发症的预防进行综述,以期为管理气管插管提供参考。     

The second-generation air-Q intubating laryngeal mask for airway maintenance during anaesthesia in adults: a report of the first 70 uses

The second-generation air-Q intubating laryngeal airway is a newer commercially available supraglottic airway device. In this retrospective review, we describe our initial clinical experience of 70 insertions. The ease and number of insertion attempts, airway leak pressure, device positioning, duration of use, success of fibreoptic-aided intubation and oropharyngeal morbidity were recorded. The intubating laryngeal airway was successfully inserted in all 770 patients and functioned adequately as a primary airway in all 57 patients in which it was used. The median airway leak pressure was 25 and 30 cmH2O for the single-use and reusable devices (P = 0.001), respectively. Fibreoptic-aided intubation using the intubating laryngeal airway as a conduit was successful in 12/13 (92%) cases. One in four (26%) patients complained of mild sore throat postoperatively before discharge. In our series, the intubating laryngeal airway performed adequately as a primary airway during anaesthesia with respect to ease of insertion, adequacy of airway maintenance, and as a conduit for intubation in both anticipated and unanticipated difficult airways. Further investigation is warranted regarding the role of the intubating laryngeal airway as a conduit for both blind and fibreoptic-aided intubation. In addition, the incidence of postoperative throat complaints deserves further scrutiny.     

声门上气道管理器具的进展

声门上气道管理(supraglottic airway management)的关键内涵是上呼吸道管理,新意在于进一步强调麻醉和药物镇静期间采用各种技术,保持上呼吸道通畅,便于实施人工通气,防止气道误吸,以及避免气管内插管。主要采用新型声门上通气器具,包括各种喉罩和喉管。1引起上呼吸道梗阻的机     

Performance characteristics of a novel reusable intermediate–volume low–pressure cuffed endotracheal tube

Study objective: To evaluate the performance of the reusable intermediate–volume low–pressure cuffed “Super Safety Yellow” (Willy Rüsch AG, P. O. Box 1620, D–71332 Waiblingen, Germany) endotracheal tube with regard to cuff seal, tube tip position, and incidence of postoperative throat complaints. The “Super Safety Yellow” was compared with the “Super Safety Clear” (W. Rusch AG), the “lo–pro” (Mallinckrodt Laboratories, Cornamady, Athlone County, Ireland), and the “red rubber” (W. Rüsch AG) tubes. Methods: Two hundred adult patients scheduled for minor surgery under standardized general anaesthesia were allocated to one of these tubes. Past–cuff leakage (indicator: orally instilled 0.2% indigocarmine) as well as intratracheal tube tip position (degree of being centred) were assessed by fibre–optic tracheoscopy. The semi–standardized interviews for the recording of postoperative sore throat were performed in double–blind fashion once a day, starting on the day of operation till p.o. day 3. Statistics: x ²–test; significance: P < 0.05. Main Results: A past–cuff leakage was found in three “red rubber” tubes. There were significant differences in tube tip position with the “Super Safety Clear” being best, and the “Super Safety Yellow” being worst centred (P = 0.010). The incidence of postoperative throat complaints showed a nonsignificant tendency in favour of the PVC–tubes. A significant number of such complaints were observed in women (P = 0.0004) and in obese patients (P = 0.011). By contrast, this incidence did not significantly differ with age, tracheal cross–sectional shape, tube tip position, use of atropine, and duration of intubation. Conclusion: Although resembling the “red rubber” tube in the incidence of postoperative throat complaints, the “Super Safety Yellow” may be an alternative to the currently used disposable tubes in anaesthesia. Its performance is comparable with regard to cuff seal and intra–cuff pressure. Additionally, it helps in reducing PVC waste and may lessen costs.     

Evolution of the extraglottic airway: a review of its history, applications, and practical tips for success

The development of the laryngeal mask airway in 1981 was an important first step toward widespread use and acceptance of the extraglottic airway (EGA). The term extraglottic is used in this review to encompass those airways that do not violate the larynx, in addition to those with a supraglottic position. Although the term extraglottic may be broad and include airways such as tracheostomy tubes, the term supraglottic does not describe a large number of devices with subglottic components and is too narrow for a discussion of modern devices. EGAs have flourished in practice, and now a wide variety of devices are available for an ever-expanding array of applications. In this review we attempt to clarify the current state of EGA devices new and old, and to illustrate their use in numerous settings. Particular attention is paid to the use of EGAs in special situations such as obstetric, pediatric, prehospital, and nontraditional "out of the operating room" settings. The role of the EGA in difficult airway management is discussed. EGA devices have saved countless lives because they facilitate ventilation when facemask ventilation and tracheal intubation were not possible. Traditionally, difficult airway management focused on successful tracheal intubation. The EGA has allowed a paradigm shift, changing the emphasis of difficult airway management from tracheal intubation to ventilation and oxygenation. EGA devices have proved to be useful adjuncts to tracheal intubation; in particular, the combination of EGA devices and fiberoptic guidance is a powerful technique for difficult airway management. Despite their utility, EGAs do have disadvantages. For example, they typically do not provide the same protection from pulmonary aspiration of regurgitated gastric material as a cuffed tracheal tube. The risk of aspiration of gastric contents persists despite advances in EGA design that have sought to address the issue. The association between excessive EGA cuff pressure and potential morbidity is becoming increasingly recognized. The widespread success and adoption of the EGA into clinical practice has revolutionized airway management and anesthetic care. Although the role of EGAs is well established, the user must know each device's particular strengths and limitations and understand that limited data are available for guidance until a new device has been well studied.     

The intubating LMA: a comparison of insertion techniques with conventional tracheal tubes

PURPOSE: To compare the performance of the intubating laryngeal mask airway (ILMA) in assisting blind tracheal intubation with conventional tracheal tubes of different curvatures and the frequency of possible associated complications. METHODS: After informed consent, 240 ASA I-II adults undergoing elective surgery participated in a randomized, single blind clinical trial to receive blind trachea intubation via ILMA with a conventional tracheal tube curved with normal (Normal group) or reversed (Reverse group) direction. More than three attempts at intubation was regarded as failure. The lowest oxygen saturation during intubation was recorded and postintubation sore throat and hoarseness were evaluated with verbal analog scales. RESULTS: The overall success rates of intubation with Normal and Reverse groups were not different (96.7% and 94.2% respectively). Successful intubation at the first attempt was higher in the Reverse group than in the Normal group (86.7% vs 75.0%, P=0.033). The incidence of sore throat was higher in the Normal group than in the Reverse group (19.2% vs 9.2% respectively, P =0.042). CONCLUSIONS: Blind trachea intubation via an ILMA with the conventional curved tracheal tube is feasible and highly successful. Reverse curve direction is preferable at the first attempt of intubation for its higher success rate and lower incidence of complications.     

Rescue supraglottic airway devices at caesarean delivery: What are the options to consider?

Tracheal intubation is considered the gold standard means of securing the airway in obstetric general anaesthesia because of the increased risk of aspiration. Obstetric failed intubation is relatively rare. Difficult airway guidelines recommend the use of a supraglottic airway device to maintain the airway and to allow rescue ventilation. Failed intubation is associated with a further increased risk of aspiration, therefore there is an argument for performing supraglottic airway-guided flexible bronchoscopic intubation (SAGFBI). The technique of SAGFBI has a high success rate in the non-obstetric population, it protects the airway and it minimises task fixation on repeated attempts at laryngoscopic tracheal intubation. However, after failed intubation via laryngoscopy, there is a lack of specific recommendations or indications for SAGFBI in current obstetric difficult airway guidelines in relation to achieving tracheal intubation.Our narrative review explores the issues pertaining to airway management in these cases: the use of supraglottic airway devices and the techniques of, and technical issues related to, SAGFBI. We also discuss the factors involved in the decision-making process as to whether to proceed with surgery with the airway maintained only with a supraglottic airway device, or to proceed only after SAGFBI.     

Tracheal tubes for maxillofacial and dental surgery

Maxillofacial and dental surgery have developed with anaesthesia. This is because of the mutual understanding that is necessary for safe and successful surgery on the ‘shared airway’. The choice of airway management technique is influenced by patient factors, surgical requirements and anaesthetic preferences. Good communication between surgeon and anaesthetist is imperative for the safety of the patient and the smooth running of the surgery. The anaesthetic considerations include: dealing with the difficult airway; the risk of obstruction, transection, disconnection or removal of the airway intraoperatively; the risk of soiling of the airway due to bleeding and surgical debris such as tooth or bone fragments; and the potential for airway compromise postoperatively. A cuffed tracheal tube with a throat pack provides the highest level of airway protection in shared airway surgery, but may not always be the most suitable technique. A north polar nasal tube provides a secure airway and excellent surgical access for surgery on the jaws, teeth, oral cavity and neck; it also allows intermaxillary fixation (wiring of the jaws) and assessment of dental occlusion. South facing preformed oral (RAE) tubes are suitable for procedures involving the nose, upper mid face and forehead. Submental intubation provides an alternative to oral and nasal tracheal intubation and is useful in selected procedures. The laryngeal mask airway (LMA) has an important role intraoperatively and provides smooth emergence from anaesthesia. Transtracheal catheter and jet ventilation is seldom used in maxillofacial anaesthesia, but is an important rescue technique. An elective tracheostomy should be considered if significant postoperative airway compromise is anticipated and may occasionally be necessary under local anaesthesia before induction. It requires surgical expertise and carries a high incidence of morbidity. This article discusses how to select appropriate tracheal tubes for maxillofacial and dental surgery.     

Pediatric airway management : cuffed endotracheal tube and other devices for tracheal intubation

Uncuffed endotracheal tubes have been commonly used in pediatric patients, but cuffed pediatric endotracheal tubes are recently introduced and stirred up a controversy. Uncuffed tubes may require multiple laryngoscopies, pollute the environment, and cause pulmonary aspiration as well as unstable ventilation. A recent study revealed that the contours of the airway and the tracheal tube are different, so that the pressure exerted on some parts of the cricoid mucosa may not be appropriate. Cuffed endotracheal tubes overcome these shortcomings if anesthesiologists pay close attention to the insertion length of the tube and cuff pressure. Laryngeal mask airway has worked well, with few complications, as a ventilatory device in pediatric patients whose tracheas cannot be intubated and/or whose lungs cannot be ventilated with conventional techniques. It is also used for a conduit for fiberoptic intubation and emergent airway with patients in the prone position. The lightwand (Trachlight) is another device for pediatric intubation and is recommended as the first-line option in patients who can be ventilated but in whom laryngoscopic intubation has failed. AirWayScope (Pentax-AWS) is a novel intubation device which combines an airway, camera and monitor It can be an epoch-making intubation device for infants and children if a smaller size is available in the future.     

Flexible, tapered-tip tube facilitates conventional orotracheal intubation by novice intubators

Orotracheal intubation is the standard technique for airway management, but several untoward airway complications are possible with this method. To avoid airway trauma caused by the tube tip during intubation, the Parker Flex-Tip tube (PFT), which has a flexible, tapered tip, was developed. It has been reported that the PFT facilitates fiberoptic orotracheal intubation and introducer-guided tracheal intubation. In this study, we compared the PFT to a standard endotracheal tube (SET), regarding the time of intubation during conventional orotracheal intubation and the incidence of postoperative sore throat and hoarseness. One hundred and thirty-four patients scheduled for elective anesthesia using orotracheal intubation were randomized to either the PFT or SET and 132 completed the study. The intubators were classified into three groups: staff anesthesiologists, inexperienced anesthesiologists, and anesthesia trainees. The tube was selected by another anesthesiologist and the time required for intubation was measured. PFT did not shorten the time required for intubation and did not reduce the incidence of sore throat and hoarseness. However, a detailed analysis revealed that the PFT decreased the time required for intubation in the anesthesia trainee group. The PFT may help novice intubators to conduct a smooth intubation.