High Cuff Pressure Research Articles

Frequencies of patient-reported sore throat, hoarseness, dysphagia, and high airway cuff pressures when manometers are used

Frequencies of patient-reported sore throat, hoarseness, dysphagia, and high airway cuff pressures when manometers are used

Reliability of Digital Artery Palpation and Pulse Oximetry Waveform As Alternatives to Radial Pulse in the Assessment of Upper Limb Injuries.

Radial pulse palpation is widely accepted as a gold standard clinical method to assess distal vascular perfusion of the upper limb. In some instances, the radial pulse may not be accessible due to splints, casts, or swelling, or the injury may be at the level or distal to the radial artery. Here, the authors assess two alternative methods of assessing perfusion of the hand more distally: palpation of the digital pulse and pulse oximetry (PO) waveform. Twenty-four healthy adult volunteers (48 hands) were assessed by two assessors. Digital artery pulses were palpated, and ease of location was recorded. A brachial cuff pressure was inflated to 20 mmHg above systolic pressure to occlude distal perfusion. Radial pulse, digital artery pulse, and PO waveform were monitored as the brachial cuff pressure was deflated in 5 mmHg increments to ascertain when each returned and compare the reliability of these tests to the gold standard of the radial pulse. The digital artery pulse was easily located in 20/24 participants, most reliably over the proximal phalanx of the index finger. With occlusion of the brachial artery, no distal pulses could be felt, and PO showed no waveform. As the brachial artery cuff pressure was incrementally deflated, the digital pulse returned with the same cuff pressure or a lower cuff pressure than the radial pulse in all cases, suggesting a high positive predictive value of radial pulse presence. PO waveform returned at a higher cuff pressure or with the same cuff pressure as the return of the radial pulse, suggesting a higher sensitivity than radial pulse palpation in assessing hand perfusion. Digital pulse palpation can be used as a surrogate method of assessing hand perfusion. When present, it can be assumed a radial pulse is present due to a high positive predictive value and no false positives seen in any participant. When absent, further investigation is required. The PO waveform was found to be more sensitive than digital or radial pulse palpation as a measure of distal perfusion, with a return of waveform prior to palpable pulses. This likely represents a more accurate clinical test of distal perfusion and can be relied upon even when pulses are not palpable.

A case of amyotrophic lateral sclerosis managed by tracheostomy and invasive ventilation in which air leaks occurred at the cuff

The patient was a 64-year-old woman who had been diagnosed with amyotrophic lateral sclerosis 8 years ago, and had been under artificial ventilation with tracheotomy for 6 years. Computed tomography indicated a dilated tracheal diameter of 29.6 ‍mm at the cuff, and a high cuff pressure of 80 ‍cmH2O. An adjustable flange tracheostomy tube with an optional length setting was used to extend the effective length by 28 ‍mm. A previously evident air leak disappeared with the change in cuff level, and cuff pressure decreased to 25 ‍cmH2O. X-ray images indicated a reduction in the size of the previous cuff area. Tracheal dilatation due to improper management of cuff pressure is a contributing factor to air leakage at the cuff area, and using an adjustable flange tracheostomy tube in an effort to resolve such air leaks is a valid option.

A Prospective Randomized Controlled Trial of the Effect of Maintenance of Continuous Cuff Pressures (20 cmH2O vs 30 cmH2O) on Postoperative Airway Symptoms in Laparoscopic Surgeries.

Recently, laparoscopic surgery has been used in many fields of surgery. It has been reported that cuff pressure becomes high during laparoscopic surgery. Increased cuff pressure may cause postoperative sore throat and hoarseness. Considering previous reports, we hypothesized that maintenance of a fixed low cuff pressure during laparoscopic surgery might be associated with low grades of postoperative sore throat and hoarseness. The participants were 100 patients between 20 and 80 years of age who were scheduled to undergo laparoscopic surgery lasting over 2 hours. Patients were randomly allocated to two groups with endotracheal tube cuff pressures fixed at 20 cmH2O (low-pressure group; LPG) and 30 cmH2O (high-pressure group; HPG). We evaluated mainly sore throat and hoarseness on postoperative day 1 using a visual analog scale (VAS; 0-10 cm). Statistical comparisons of values were performed using the unpaired t-test, Mann-Whitney U-test, and chi-square test with values of p < 0.05 considered statistically significant. There were no significant differences in background characteristics between the two groups. Median postoperative scores for the LPG and HPG were 1 (interquartile range, 0-3) and 0 (0-2; p = 0.560) for sore throat and 2 (0-4) and 1 (0-3; p = 0.311) for hoarseness, respectively, and the differences were not significant. The effects of maintenance of a fixed low cuff pressure and a fixed high cuff pressure on the degrees of postoperative sore throat and hoarseness after laparoscopic surgery were the same and the grades were low.

Towards continuous non-invasive blood pressure measurements-interpretation of the vasculature response to cuff inflation.

Blood pressure (BP) surrogates, such as pulse transit time (PTT) or pulse arrival time (PAT), have been intensively explored with the goal of achieving cuffless, continuous, and accurate BP inference. In order to estimate BP, a one-point calibration strategy between PAT and BP is typically used. Recent research focuses on advanced calibration procedures exploiting the cuff inflation process to improve calibration robustness by active and controlled modulation of peripheral PAT, as measured via plethysmograph (PPG) and electrocardiogram (ECG) combination. Such methods require a detailed understanding of the mechanisms behind the vasculature's response to cuff inflation; for this, a model has recently been developed to infer the PAT-BP calibration from measured cuff-induced vasculature changes. The model, while promising, is still preliminary and only partially validated; in-depth analysis and further developments are still needed. Therefore, this work aims to improve our understanding of the cuff-vasculature interaction in this model; we seek to define potential opportunities and to highlight which aspects may require further study. We compare model behaviors with clinical data samples based on a set of observable characteristics relevant for BP inference and calibration. It is found that the observed behaviors are qualitatively well represented with the current simulation model and complexity, with limitations regarding the prediction of the onset of the distal arm dynamics and behavior changes at high cuff pressures. Additionally, a sensitivity analysis of the model's parameter space is conducted to show the factors that influence the characteristics of its observable outputs. It was revealed that easily controllable experimental variables, such as lateral cuff length and inflation rate, have a significant impact on cuff-induced vasculature changes. An interesting dependency between systemic BP and cuff-induced distal PTT change is also found, revealing opportunities for improved methods for BP surrogate calibration. However, validation via patient data shows that this relation does not hold for all patients, indicating required model improvements to be validated in follow up studies. These results provide promising directions to improve the calibration process featuring cuff inflation towards accurate and robust non-invasive blood pressure estimation.

High peak inspiratory pressure may be associated with intraoperative coughing during neurosurgery under general anesthesia without neuromuscular blockade: a retrospective study

BackgroundThe endotracheal cuff pressure depends on the airway pressure during positive-pressure ventilation. A high endotracheal cuff pressure may be related to intraoperative coughing, which can be detrimental during neurosurgery. We investigated the incidence of intraoperative coughing and its association with peak inspiratory pressure (PIP) during neurosurgery under general anesthesia without neuromuscular blockade.MethodsThis retrospective study divided 1656 neurosurgical patients who underwent total intravenous anesthesia without additional neuromuscular blockade after tracheal intubation into high (PIP > 21.6 cmH2O, n = 318) and low (PIP ≤ 21.6 cmH2O, n = 1338) PIP groups. After propensity score matching, 206 patients were selected in each group. Demographic, preoperative, surgical, and anesthetic data were collected retrospectively from electronic medical records and continuous ventilator, infusion pump, and bispectral index data from a data registry.ResultsIntraoperative coughing occurred in 30 (1.8%) patients, including 9 (0.5%) during the main surgical procedure. Intraoperative coughing was more frequent in the high PIP group than in the low PIP group before (14/318 [4.4%] vs. 16/1338 [1.2%], P < 0.001) and after (13/206 [6.3%] vs. 1/206 [0.5%], P = 0.003) propensity score matching. In multivariable logistic regression analysis after propensity score matching, a high PIP (odds ratio [95% confidence interval] 14.22 [1.81-111.73], P = 0.012), tidal volume divided by predicted body weight (mL/kg, 1.36 [1.09–1.69], P = 0.006), and surgical duration (min, 1.01 [1.00–1.01], P = 0.025) predicted intraoperative coughing.ConclusionThe incidence of intraoperative coughing was 1.8% in neurosurgical patients undergoing general anesthesia without neuromuscular blockade and might be associated with a high PIP.

シングルルーメンチューブを用いた緊急挿管後に大量皮下気腫を生じた気管損傷の1例(A case of tracheal rupture with massive subcutaneous emphysema after emergency tracheal intubation with a single–lumen tube)

要旨 気管挿管は救急医療において日常的に行われている手技であるが，挿管後の気管損傷は稀かつ死亡リスクが高いうえ，症状発現までの時間も一定ではないため診断や原因検索に難渋する。また，発生率はダブルルーメンのほうが多く，シングルルーメンではごく僅かである。今回我々は，シングルルーメンを用いた緊急気管挿管後に大量の皮下気腫を呈したものの，良好な転帰を経た気管膜様部損傷の1例を経験したので報告する。症例は80歳代女性，明け方に呼吸困難で救急搬送された。来院時は不穏状態かつ，リザーバーマスク10L/分の高濃度酸素投与下でSpO2 86%であった。画像検査にて急性心不全による肺水腫と診断し初療室で緊急挿管を行い集中治療室管理となったが，入室時のカフ圧が高値を示していた。挿管数時間後に全身の皮下気腫を認め精査にて気管膜様部に4cmに渡る縦方向の裂傷を確認し，カフ圧損傷に伴う気管膜様部損傷と推測した。挿管後気管損傷に至る原因は患者側要因と医療側要因が複雑に絡むため原因不明な場合も多いが，双方のリスクを吟味し発症を予防するための具体的な行動指標を考察する。

Effects of Low-Load Blood Flow Restriction Resistance Training on Muscle Strength and Hypertrophy Compared with Traditional Resistance Training in Healthy Adults Older Than 60 Years: Systematic Review and Meta-Analysis.

There is clinical interest in determining the effects of low-load blood flow restriction (LL-BFR) resistance training on muscle strength and hypertrophy compared with traditional high- and low-load (HL and LL) resistance training in healthy older adults and the influence of LL-BFR training cuff-pressure on these outcomes. A search was performed on the MEDLINE, PEDro, CINHAL, Web of Science, Science Direct, Scopus, and CENTRAL databases. The analysis included 14 studies. HL resistance training produces a small increase in muscle strength (eight studies; SMD, -0.23 [-0.41; -0.05]) but not in muscle hypertrophy (six studies; (SMD, 0.08 [-0.22; 0.38]) when compared with LL-BFR resistance training. Compared with traditional LL resistance training, LL-BFR resistance training produces small-moderate increases in muscle strength (seven studies; SMD, 0.44 [0.28; 0.60]) and hypertrophy (two studies; SMD, 0.51 [0.06; 0.96]). There were greater improvements in muscle strength when higher cuff pressures were applied versus traditional LL resistance training but not versus HL resistance training. LL-BFR resistance training results in lower muscle strength gains than HL resistance training and greater than traditional LL resistance training in healthy adults older than 60 years. LL-BFR resistance training promotes a similar muscle hypertrophy to HL resistance training but is greater than that of traditional LL resistance training. Applying cuff pressures above the limb occlusion pressure could enhance the increases in muscle strength compared with traditional LL resistance training.

A Comparison between High and Low Cuff Pressures on Muscle Oxygen Saturation and Recovery Responses Following Blood-Flow Restriction Resistance Exercise.

The aim of the study was to compare the recovery response and muscle oxygenation of a blood-flow restriction resistance exercise (BFR) session with high [HP: 80% of the arterial occlusion pressure (AOP)] and low cuff pressure (LP: 40% of AOP). Both exercise sessions included 4 sets to failure at the barbell preacher curl exercise. Twelve resistance trained men (27.4 ± 5.0 years; 83.5 ± 11.6 kg; 176.6 ± 7.0 cm) performed each protocol in a counterbalanced, randomized order. Maximal isometric force, muscle morphology and muscle soreness of the biceps brachii muscle were assessed at baseline, 15-min, 60-min and 24-h post each testing session. In addition, muscle oxygen saturation (SmO2) was assessed during each training session. A lower number of repetitions (p = 0.013) was detected in HP compared to LP. A lower SmO2 (p < 0.001) was detected in the recovery time between the sets in HP (mean: 47.6 ± 15.7%) compared to LP (mean: 68.9 ± 7.2%). No differences between the two trials (p > 0.05) were noted for isometric force, muscle architecture and soreness at any timepoint. Results indicate that, despite a high cuff pressure may induce a more hypoxic condition compared to a lower cuff pressure, recovery responses may not be affected.

The impact of esophageal device insertion on cuff pressure of endotracheal tube: a literature review and meta-analysis

The impact of intraoperative esophageal device insertion (EDI) on endotracheal tube (ET) cuff inflation pressure remains unclear. Electronic databases including Medline, Embase, Google scholar, Web of Science™ and Cochrane Central Register of Controlled Trials were searched for studies involving EDI after placement of ETs from inception to July 7, 2022. The primary outcome was risk of high cuff pressure, while the secondary outcomes were increases in cuff pressure following EDI. Difference between adults and children was investigated with subgroup analysis. There were ten eligible studies (observation study, n = 9, randomized controlled study, n = 1) involving a total of 468 participants. EDI notably increased the risk of high cuff pressure (n = 7, risk ratio: 12.82, 95% confidence interval: 4.9 to 33.52, subgroup analysis: p = 0.008). There were significant elevations in cuff pressure in adults and children both during (13.42 and 7.88 cmH2O, respectively, subgroup analysis: p = 0.15) and after (10.09 and 3.99 cmH2O, respectively, subgroup analysis: p = 0.0003) EDI. Our results revealed an over 12-fold increase in the risk of high endotracheal tube cuff pressure in patients, especially adults, receiving EDI under endotracheal anesthesia. There were significant increases in both adults and children despite a higher increase in the former after device insertion.

Sealing mechanism study of laryngeal mask airways via 3D modelling and finite element analysis

Proper sealing of laryngeal mask airways (LMAs) is critical for airway management in clinical use. Understanding the sealing mechanism can significantly help front-line anaesthetists to reduce the incidence of adverse events. However, anaesthetists, who may not have the most substantial engineering backgrounds, lack intuitive ways to develop an understanding of the LMA sealing mechanism effectively. The paper aims to study the LMA-pharynx sealing mechanisms from the perspective of front-line anaesthetists. We use a computer-aided 3D modelling technique to visualise the LMA—pharynx interactions, which helps anaesthetists identify the critical areas of complications. Furthermore, we conduct a quantitative pressure distribution analysis of the LMA-pharynx contacting surface using the finite element analysis technique, which helps further understand the sealing mechanics in those areas. We present two cases studies based on one male volunteer, aged 50, inserted with a ProSeal LMA. In the first case, a relatively low cuff pressure (CP) was applied to simulate the clinical circumstances in which complications related to air leakage are most likely to happen; in the second case, we increase the CP to a relatively high value to simulate the scenarios with an increased risk of complications related to high mucosal pressure. The experiments suggest the follows: (1) Sore throat complications related to high mucosal pressure is most likely to occur in the hypopharynx with a high CP setting, particularly in the areas where the cricoid cartilage presses the mucosa. (2) The narrow hyoid bone super horn width likely causes LMA insertion difficulties. (3) Insufficient CP will significantly increase the risk of air leakage in the oropharynx. A complete sealing pressure line in the contacting surface will be formed with sufficient CP, thereby preventing the air leakage into the oral.

Under or overpressure: an audit of endotracheal cuff pressure monitoring at the tertiary care center.

BackgroundMechanical ventilation is a lifesaving intervention for critically ill patients but can produce the major complication of ventilator-associated pneumonia (VAP). Inappropriately inflated endotracheal tubes cause potential harm due to high or low pressure; this can be prevented through monitoring protocols.MethodsA cross-sectional study of 348 cuff pressure readings was performed with intubated and mechanically ventilated patients to evaluate the exact proportion of patients in intensive care units (ICUs) where the cuff pressure is optimal and to identify the ICUs where device-based monitoring is available to produce a lower proportion of sub-optimal cuff pressure cases. Every three days, cuff pressure was assessed with a handheld cuff pressure manometer. The corresponding VAP rates of those ICUs were obtained from the hospital infection control department.ResultsCuff pressure of 40.2% was the lower cutoff for the high category, that of optimal was 35.3%, and the highest cutoff of sub-optimal was 24.4%. This study also showed ICUs that had cuff pressure monitoring devices and protocols. Active measurement protocols had a higher proportion of optimal cuff pressure (58.5%) and a lower proportion of sub-optimal and high cuff pressure (19.5% and 22.0%) compared to ICUs with no device-based monitoring protocols. Furthermore, the VAP rate of ICUs exhibited a weak positive correlation with sub-optimal cuff pressure.ConclusionsDevice-based cuff pressure monitoring is essential in maintaining adequate cuff pressure but often is inadequate, resulting in high readings. Therefore, this study suggests that device-based cuff pressure monitoring be practiced.

Intraoperative Cuff Pressure Measurements of Endotracheal Tubes in the Operating Theater

Abstract Background: Endotracheal tube (ETT) intracuff pressure (PINTRACUFF) monitoring is not a mandatory part of daily anesthetic practice in many countries. Correct PINTRACUFF is required to ensure adequate ventilation, to prevent aspiration, and to avoid complications. The aim of this study was to objectively measure the PINTRACUFF in ETTs among patients from an Australian tertiary hospital to define the range of PINTRACUFF values seen in a setting without the use of routine objective monitoring. Patients and Methods: A prospective single-center audit of PINTRACUFF of 268 elective and emergency surgical patients undergoing general anesthesia with an ETT was performed. PINTRACUFF values were measured with a calibrated cuff manometer following the induction of anesthesia. Patient characteristics were compared between three patient groups of measured PINTRACUFF values: 20 cmH2O, 20–30 cmH2O, and &gt;30 cmH2O. Results: To estimate the PINTRACUFF, only the auditory method was used among 66.0% of the patients, the tactile method was used in 18.3%, and the remainder used both or other methods. Following induction of anesthesia, the mean PINTRACUFF was 31.0 cmH2O (±standard deviation 16.4). The PINTRACUFF was &lt;20 cmH2O for 54 patients (20.1%), and it exceeded 30 cmH2O for 103 patients (38.4%). Patients with a PINTRACUFF &gt;30 cmH2O had a marginally higher body mass index (BMI) compared to patients with a PINTRACUFF &lt;30 cmH2O (P = 0.002). Patients with higher BMIs and smaller ETTs had higher cuff pressures. Conclusion: This study demonstrates that replacing subjective estimation methods with mandatory cuff pressure measurement can ensure that normal values are achieved during anesthesia.

Comparison of Ambu AuraGain at low cuff pressure, Ambu AuraGain at high cuff pressure and i-gel in relation to incidence of postoperative upper airway complications.

Background and Aims:Postoperative upper airway complications are frequently encountered with the use of supraglottic airway devices (SADs). Cuff pressure is one of the risk factors for upper airway complications with SADs. Among SADs, i-gel has shown lesser incidence. The effect of different cuff pressures on the incidence of postoperative upper airway complications is not known with Ambu AuraGain and nor has Ambu AuraGain been compared with i-gel in this regard. So, we undertook this study.Methods:A total of 200 patients undergoing elective laparoscopic surgery were randomised into 3 groups based on the SAD used and intra-cuff pressure: i-gel (IG) (n = 66); Ambu AuraGain at 25 cmH2O cuff pressure (AL) (n = 67); and Ambu AuraGain at 60 cmH2O cuff pressure (AH) (n = 67). The oropharyngeal leak pressures (OLPs) were measured after insertion and generation of carboperitoneum. An observer who was blind to the intraoperative details assessed the patients for two postoperative days for sore throat, dysphagia, dysphonia, or any other upper airway complications.Results:The OLPs before and after carboperitoneum in the 3 groups were (IG-24.22 ± 7.87 and 28.31 ± 8.52, AL-24.40 ± 5.84 and 26.94 ± 5.93, AH-25.02 ± 5.02 and 28.91 ± 5.6) cmH2O (P = 0.747 and P = 0.231). The overall incidence of postoperative sore throat among the 3 groups was: IG-5.7%, AL-14.9%, and AH-17.9%; P = 0.135. Dysphagia was seen only with Ambu AuraGain at high pressure in 4 patients (5.97%) (P = 0.017).Conclusion:Limiting cuff pressure in Ambu AuraGain to 25, as against 60 cmH2O, does not affect the OLP but has the potential of reducing the incidence of dysphagia.

Dynamic functional connectivity underlying temporal summation of pain in fibromyalgia

Compared to healthy controls (HC), fibromyalgia (FM) patients exhibit enhanced temporal summation of pain (TSP) – i.e. perception of increasingly greater pain in response to repetitive or sustained noxious stimuli. Previous neuroimaging studies have linked static functional connectivity (sFC) and stimulus-evoked brain fMRI response to enhanced TSP in FM patients. However, dynamics of brain organization in FM underlying ongoing changes in pain perception, such as that during TSP, is not known. The purpose of this study was to investigate the dynamic changes in functional brain connectivity (dFC) occurring during TSP in FM. We collected high temporal resolution (TR=1.25s) 6-minute resting-state (REST) and tonic leg cuff pressure pain (PAIN) accelerated fMRI brain scan from 84 FM patients and 38 HCs. Pain ratings were collected retrospectively for each 2-minute block of the PAIN scan, and TSP was calculated as last minus first pain rating. We used an instantaneous phase synchrony analysis approach to estimate dFC, followed by the application of a multi-slice community detection algorithm to reveal the dynamic community organization of the brain over time. We found that FM patients exhibit greater TSP than HCs (meanFM = 17.93, meanHC = 9.47, p = 7.58 × 10-4). In FM (and not HC), during PAIN versus REST, fMRI signal from the contralateral leg area of primary somatosensory cortex (S1leg) spent more time in the same community as salience network regions. However, both FM and HC groups showed decreased S1leg community enmeshment with other somatotopic areas of S1 during PAIN compared to during REST. Furthermore, longer and more consistent enmeshment of the sensorimotor and salience communities throughout the PAIN scan was associated with greater TSP in FM patients. Overall, this study corroborates our prior tonic cuff pain static connectivity results and reveals that dynamics in brain organization track changes in pain perception reflecting TSP in FM. NCCIH, NIH R61/R33-AT009306 (VN) and NIAMS, NIH R01-AR064367 (VN, RRE).

Tracheoinnominate fistula due to high-riding innominate artery: A rare but potentially life-threatening complication following long-term tracheostomy

Tracheoinnominate fistula (TIF) is a rare but potentially life-threatening complication after tracheostomy. TIF was mostly observed within 7–21 days after tracheostomy but can present even years after tracheostomy. The risk factors for TIF are high cuff pressure, mucosal trauma from malpositioned cannula tip, low tracheal incision, excessive neck movement (hyperextension), radiotherapy, prolonged intubation, and high-riding innominate artery (HRIA). HRIA is also a rare anatomical variation of the innominate artery (IA) whereas IA bifurcates above the sternoclavicular joint. We report a rare case of TIF in a patient with HRIA, who presented with airway bleeding 2 months after percutaneous tracheostomy (PT) and was successfully managed with aggressive resuscitation and midline sternotomy. Knowledge of anatomical variation of the aortic arch and its major branches is essential for the physician who is routinely performing or managing tracheostomy. All the health-care workers involved in the management of tracheostomy should bear this complication in mind while dealing with any airway bleed. We recommend the routine use of bedside neck ultrasonography before all PTs to locate any aberrant vessel within the vicinity of tracheostoma to prevent this complication.

Evaluation of I-Gel, Ambu-AuraGain at low and high cuff-pressure for postoperative airway complications

Evaluation of I-Gel, Ambu-AuraGain at low and high cuff-pressure for postoperative airway complications

High Tracheal Tube Cuff Pressure During Thyroidectomy is Associated with Recurrent Nerve Injury.

High Tracheal Tube Cuff Pressure During Thyroidectomy is Associated with Recurrent Nerve Injury.

Changes in Tracheal Tube Cuff Pressure and Recurrent Laryngeal Nerve Conductivity During Thyroid Surgery.

The aetiology of recurrent laryngeal nerve (RLN) neurapraxia is unclear in most RLN palsies post-thyroidectomy. We hypothesised that high intralaryngeal pressures impede RLN conductivity, in turn contributing to RLN palsy. Therefore, we measured tracheal tube (TT) cuff pressure (as a surrogate for intralaryngeal pressure) and RLN conduction during ten standard manoeuvres in thyroidectomy, to assess for correlation between cuff pressure and RLN conductivity. A prospective cohort study of thyroidectomy during 2018. For each thyroid lobe, TT cuff pressure was continuously measured via an air pressure transducer. RLN conduction (amplitude and latency) was measured using continuous neuromonitoring. Changes in mean TT cuff pressure and median nerve conduction from baseline measurements were analysed using Student's t test and Wilcoxon signed-rank test. In a total of 50 RLNs, the mean baseline TT cuff pressure of 19.5 ± 8.9mmHg increased significantly to 22.0mmHg during anteromedial rotation of the thyroid (p < 0.05). RLN conduction changed during manipulation of the superior thyroid pole with shortening of latency (-0.49% from baseline, p = 0.05) and reduction in amplitude (-12.0% from baseline, p = 0.02). The timing of these deviations did not correlate with the increased TT cuff pressure. In three cases of temporary RLN palsy, the mean cumulative case TT cuff pressure was significantly higher (24.8mmHg, p = 0.02). This study demonstrates that TT cuff pressure and RLN conductivity can change significantly with manipulation of the thyroid and that high TT cuff pressures may be associated with RLN injuries.

Tracheal tube cuff pressure monitoring: Assessing current practice in critically ill patients at Chris Hani Baragwanath Academic Hospital.

Intubated patients with a high tracheal tube cuff pressure (CP) are at risk of developing tracheal or subglottic stenosis. Recently an increasing number of patients have presented to our hospital with these complications. To determine the frequency of tracheal tube CP measurements and the range of CP and to explore nursing knowledge regarding CP monitoring. Frequency of CP measurement was assessed using a prospective chart review, followed by an interventional component. In the final stage nurses completed a self-administered questionnaire. A total of 304 charts from 61 patients were reviewed. Patients' ages ranged from 1 to 71 years, with a male preponderance (1.5:1). The majority of charts (87%) did not reflect a documented CP measurement and only 12 charts showed at least one measurement per shift. Only 17% of recorded CPs were within the recommended range; 59% were too low. The questionnaire was completed by only 51% of the 75 respondents. Nursing experience ranged from 3 to 35 years and 92% of respondents were trained in critical care. Knowledge of current critical care CP monitoring guidelines was reported by 62% of the respondents (n=23/37). Only 53% (20/38) reported routinely measuring CP. Almost all respondents (94%) knew of at least one complication of abnormal CP. Having a basic knowledge of CP measurement, having awareness of the complications of abnormal CP and the availability of national best practice guidelines did not translate into appropriate ICU practice. Research into effective implementation strategies to achieve best practice is needed. Basic knowledge of cuff pressure measurement may not always result in best practice.Improvement in current practice requires research into effective implementation strategies.