Loss Of Tidal Volume Research Articles

An Innovative Technique to Prevent Air Leaks from Cervical Esophagostomy during Face Mask Ventilation.

The objective of the study was to report the indigenous use of an electrocardiography (ECG) electrode in successfully occluding the Cx-esophagostomy to prevent inadvertent loss of tidal volume. Twenty-nine observations were recorded on 27 patients (mean age: 10.9 months; male:female = 2.6:1). The oral cavity, pharynx, and Cx-esophagostomy were cleared of saliva. Peristomal area was cleaned with dry gauze and dried with alcohol. Latex-free, 50 mm, ECG electrode was pasted symmetrically over the Cx-esophagostomy. The efficacy of the electrode was assessed using a five-point algorithm: (i) collapse of reservoir bag, (ii) chest expansion, (iii) ballooning of electrode, (iv) cotton-wisp test, and (v) change in compliance with manual compression of the electrode. Subgroup analysis was conducted for laterality and health of Cx-esophagostomy. Study cohort: Cx-esophagostomy was located on the left in 58.26% (n = 17/29) patients. The health of Cx-esophagostomies was graded from I to IV (n = 9, 16, 3, and 1, respectively). The collapse of the reservoir bag and chest rise indicated successful ventilation. Ballooning of the electrode with each breath was observed in 79% (23/29) patients. Partial separation of the electrode from the skin (exaggerated with each breath) was observed in 10.3% (3/29) patients (Group I: n = 1, Group III: n = 1, and Group IV: n = 1). This was related to poor local preparation or pooling of saliva (n = 1; Group I: resolved with procedural re-application of a fresh electrode) and underlying skin condition (n = 2; Groups III and IV: resolved only temporarily with re-application). The cotton-wisp test was positive in two additional patients (1 each in Groups II and III) and was related to the pooling of saliva. No change in compliance was observed with manual compression of the electrode. No difference in success was observed between left and right Cx-esophagostomies. Overall success with this technique was 82.8% with a potential for 100% in those with peristomal health graded I-III. The ECG electrode is a technically simple, cost-effective, and widely available device, instrumental in addressing the problem of air leak through Cx-esophagostomy during face mask ventilation before intubation.

Pre-hospital emergency cricothyrotomy in dogs part 2: Airway sealing and ventilation using cricothyrotomy tubes.

Cricothyrotomy (CTT) has been recommended for use in the pre-hospital setting for military working dogs and Operational K9s during airway emergencies. Although the CTT can establish a patent airway for spontaneous ventilation, the ability to seal the airway and provide positive pressure ventilation (PPV) using tubes designed for humans has not been determined. Using various CTT tubes placed in cadaver dog airways, this study aimed to determine: (1) Whether the tube cuff could create a functional airway seal with safe intra-cuff pressures; (2) The magnitude of delivered tidal volume (TV) loss during a standard breath to assess the possibility of delivering an adequate tidal volume with a bag-valve device (BVM); (3) The best performing tubes for either test; (4) The reasons behind the findings using observations from upper airway endoscopy, dissection, and measurements. Cadaver dogs of similar weights to MWD and Operational K9 breeds had various CTT tubes placed including three from commercial kits, a standard endotracheal tube, and a tracheostomy tube. The minimum occlusive volume technique was used to inflate the tube cuff and a pressure ≤ 48 cm H2O with an adequate seal was considered successful. Individual TVs were calculated for each dog and added to the volume lost during delivery of a standard breath from an ICU ventilator. Endoscopy and airway dissection were performed to assess the relationship between tubes cuffs and the airway. The tubes from the CTT kits performed poorly with regards to producing an airway seal with the H&H tube failing to seal the airway all tests. Tracheal dimensions were significantly associated with successful airway sealing (P = 0.0004). Tidal volume loss could be compensated using a BVM in 34/35 tests with the H&H tube in cadaver 8 the only to fail. Tracheal airway sealing is influenced by airway anatomy when tube cuffs are inflated to a target pressure and larger tubes do not always provide a better seal. The CTT tubes tested have the potential to facilitate ventilation with a BVM under the conditions set in this study. The 8.0 mm endotracheal tube performed the best and the H&H the worst in both tests.

Dead space washout by intentional leakage flow during conventional ventilation of premature infants-an experimental study.

ObjectiveInvasive mechanical ventilation poses a strong risk factor for the development of chronic lung disease in preterm infants. A reduction of the dead space as part of the total breathing volume would reduce the ventilation effort and thereby lower the risk of ventilator‐induced lung injuries. In this experimental study, we compared the efficacy of mechanical dead space washout via uncontrolled and controlled leakage flow in their ability to eliminate CO2 during conventional ventilation in preterm infants.MethodsThree frequently used neonatal ventilators, operating under standard conventional ventilating parameters, were individually connected to a test lung. To maintain a constant physiological end‐expiratory pCO2 level during ventilation, the test lung was continuously flooded with CO2. A side port in the area of the connector between the endotracheal tube and the flow sensor allowed breathing gas to escape passively or in a second experimental setup, regulated by a pump. Measurements of end‐expiratory pCO2 were taken in both experiments and compared to end‐expiratory pCO2 levels of ventilation without active dead space leakage.ResultsFollowing dead space washout, a significant reduction of end‐expiratory pCO2 was attained. Under conditions of uncontrolled leakage, the mean decrease was 14.1% while controlled leakage saw a mean reduction of 16.1%.ConclusionWashout of dead space by way of leakage flow is an effective method to reduce end‐expiratory pCO2. Both controlled and uncontrolled leakage provide comparable results, but precise regulation of leakage allows for a more stable ventilation by preventing uncontrolled loss of tidal volume during inspiration.

BRONCHOPLEURAL FISTULA? ENDOBRONCHIAL VALVES TO THE RESCUE

TOPIC: Procedures TYPE: Fellow Case Reports INTRODUCTION: Bronchopleural fistula (BPF) is a sinus tract between the main stem, lobar, or segmental bronchus and the pleural space. Most commonly seen as a complication of lung resection surgery with morbidity ranging from 25%-71%. Treatment of BPF primarily is surgical closure but might but bronchoscopic interventions can be considered in certain cases. Here we present a case of endobronchial valves (EBVs) being used as a bridge to surgery. CASE PRESENTATION: A 60-year-old man presented muscle weakness, anterior mediastinal mass and respiratory failure requiring intubation. Diagnosis of myasthenic crisis was made and he underwent three rounds of plasmapheresis. Subsequently, video assisted thoracoscopy with resection of the thymoma was done but the surgery was complicated with need for right pneumonectomy. On post-operative day 6, patient developed right sided tension pneumothorax requiring a 28 Fr chest tube placement resulting in continuous grade IV air leak. Chest CT scan revealed a right hydropneumothorax (Fig 1). Diagnostic bronchoscopy on day 10, showed absence of right main stem bronchus along with a 4mm bronchopleural fistula (Fig 2). Cultures from the bronchoscopy grew methicillin sensitive staphylococcus aureus and he was started on appropriate antibiotics. He continued to have PAL along with significant tidal volume loss which led to failed weaning on the ventilator. Unfortunately, he was deemed not a surgical candidate due to his ventilator dependence from pneumonia and poor nutritional status. On day 14, we repeated bronchoscopy and fibrin sealant was applied through a guide sheath, down the working channel which reduced the air leak but still persisted. Next day, bronchoscopy with deployment of size 5 spiration endobronchial valves was performed (Fig 3) which led to cessation of air leak and on day 20, patient was successfully weaned off ventilator support. Patient was treated for the empyema for 4 weeks and chest tubes were thereafter removed. He was then discharged to subacute rehabilitation after 57 days of hospitalization and 8 weeks later underwent surgical closure. DISCUSSION: BPF diagnosis and management requires a multidisciplinary approach. Patients with poor cardiopulmonary status, the risks of general anesthesia and surgical intervention pose a challenge. A variety of bronchoscopic options like EBVs, stents, ASD closure devices and occlusive material can be considered, primarily as temporizing measures. EBVs allow retrograde passage of air and infected secretions while blocking anterograde airflow. This reduces or stops the air leak and promotes healing. Their use in our patient allowed for weaning from high levels of oxygen support and liberation from mechanical ventilation. CONCLUSIONS: EBV placement is a minimally invasive procedure which can be performed to help with PAL associated with small BPF (<5mm) when surgery is not an option. REFERENCE #1: M. Lois, M. Noppen, Bronchopleural fistulas: an overview of the problem with special focus on endoscopic management, Chest 128 (2005) 3955–3965. REFERENCE #2: Giddings O, Kuhn J, Akulian J. Endobronchial valve placement for the treatment of bronchopleural fistula: a review of the current literature. Curr Opin Pulm Med. 2014 Jul;20(4):347-51. doi: 10.1097/MCP.0000000000000063. PMID: 24811833. REFERENCE #3: Mahajan AK, Verhoef P, Patel SB, Carr G, Kyle Hogarth D. Intrabronchial valves: a case series describing a minimally invasive approach to bronchopleural fistulas in medical intensive care unit patients. J Bronchology Interv Pulmonol. 2012;19(2):137-141. doi:10.1097/LBR.0b013e318251c897 DISCLOSURES: No relevant relationships by Tejaswi Nadig, source=Web Response

Supraglottic Airway Devices for Elective Pediatric Anesthesia: I-gel versus Air-Q, Which is the Best?

Objectives:The objectives of the study were to compare the insertion facility, the effect on hemodynamic parameters, and effective ventilation using I-gel versus Air-Q supraglottic airway devices (SADs) for pediatric patients undergoing short-duration surgical procedures.Patients and Methods:One hundred and fifty children aged 3–10 years were randomly divided into two equal groups: Group I received I-gel and Group Q received Air-Q SAD. All patients were anesthetized by sevoflurane inhalation using a face mask without neuromuscular blockade. Study outcomes included SAD insertion success rate (SR), insertion time, anatomic alignment of the SAD to the larynx as judged using fiberoptic bronchoscope (FOB) inserted through the SAD, and tidal volume leak, and incidence of postoperative complications.Results:Total and first attempt SRs were 97.3% and 85.3% for I-gel and 94.7% and 82.7% respectively, for Air-Q with nonsignificant differences. However, I-gel insertion time (12.3 ± 3.6 s.) was significantly (P = 0.034) shorter than Air-Q (13.7 ± 4.2 s). FOB grading of laryngeal view through SAD was better with I-gel but without significant difference for patients who had view Grades 1-2. Percentage of tidal volume loss was significantly decreased at 5 min after insertion than immediately after insertion, in all patients, with a nonsignificant difference in favor of I-gel. Intraoperative hemodynamic changes and postoperative complications showed a nonsignificant difference between both the groups.Conclusion:Both Air-Q and I-gel SAD provided advantages for pediatric anesthesia during short-duration surgical procedure with nonsignificant differences. However, I-gel SAD required a shorter insertion time and provided a high SR which is satisfactory for trainees and during an emergency. I-gel SAD allowed minimization of tidal volume leak and gastric inflation and is associated with infrequent complications.

Virtues of Using a Double Lumen Tube for Anesthesia in Patients with Endobronchial Tumours Requiring Open Lung Resection or Bronchoplastic Procedures

Objective The benefits and risks of using double lumen tube (DLT) in open thoracotomy are not well studied and the relative contraindication for using it in cases of endobronchial tumours is not proven. In this study, we compared our experience with using DLT versus single lumen tube (SLT) for anesthesia in patients requiring an open thoracotomy for resection of endobronchial tumours. Methods A prospective observational study was performed in a single tertiary care university hospital in patients with endobronchial tumours anesthetized with single and double lumen tubes for open thoracotomy procedures over a period from 2010 till 2018. Results One hundred and six patients with endobronchial tumours were studied. There were 76 males. Median age was 32 years (14 - 62). In 96 cases, endobronchial pathology was a typical carcinoid. 58 patients were anesthetized using a DLT and 48 using a SLT. Four cases of near miss from potentially fatal intraoperative tumour migration occurred in the SLT group (p = 0.025). There was only one case of mild tumour bleeding from the DLT group and time of insertion was longer (16.2 vs. 4.5 min p Conclusions We conclude that it is safe to place a double lumen endo tracheal tube for patients with endobronchial tumours requiring open lobectomies or bronchoplastic procedures. An additional benefit of DLT use is increasing surgical satisfaction by reducing spillage and tidal volume loss during surgical anastomosis of the open airway.

Comparison of laryngeal mask airway supremeTM as non-inflatable cuff device and self-pressurized air-QTM in children: Randomized controlled non-inferiority study.

Background: Supraglottic airway (SGA) device with non-inflatable cuff reduce the airway complications associated with cuff hyperinflation. The aim of the study is to determine whether the default setting of Supreme is as effective as the non-inflatable cuff devices. The oropharyngeal leak pressure was measured and compared between the Supreme and Air-Q, a typical non-inflatable cuff device. We hypothesized that the default setting of Supreme is non-inferior to the the Air-Q self-pressurized (SP) in respect to the oropharyngeal leak pressure.Methods: Eighty-four patients aged 1 to 7 years who were scheduled for general anesthesia, participated in the study. The patients were randomly assigned to Supreme group (n = 41) or Air-Q SP group (n = 43). We considered that the primary outcome, oropharyngeal leak pressure of Supreme group would be non-inferior to the Air-Q SP group, within 3 cmH2O. Other outcomes included tidal volume loss, difficulty of insertion, insertion time, and complications.Results: The oropharyngeal leak pressure of the Supreme and Air-Q SP was 19.9 ± 4.1 cm H2O and 17.4 ± 2.9 cm H2O, respectively. The mean differences of 2 devices (Air-Q SP—Supreme) were −2.5 cm H2O, (95% confidence interval [−4.0 to −0.9], P = .002). The upper CI was smaller than the non-inferiorty margin (3 cm H2O). This result suggested that the default setting of Supreme was superior to the Air-Q SP with respect to the oropharyngeal leak pressure. However, there were no significant differences in tidal volume loss over time, ease of device insertion score, insertion time, and complications.Conclusions: The Supreme can be used in the default setting in pediatric patients accordingly in terms of tolerable leak pressure and the stability for mechanical ventilation compared with Air-Q SP.

Adverse Events during Inter-Hospital Transports on Extracorporeal Membrane Oxygenation

Background: Extracorporeal membrane oxygenation (ECMO) may be a lifesaving rescue therapy in refractory, severe respiratory, and/or circulatory failure. To provide the best cost efficiency to the population served and patient outcome, ECMO therapy should be provided by specialized high volume ECMO centers. This requires dedicated transport teams to organize and perform these complex transports. Concerning adverse events and complications during these transfers, only a minimal amount of data has been published. Methods: To shed light on this matter, all medical transport records from transports on ECMO between January 2010 and June 2016 were analyzed. The data was classified in constituent groups and categorized to risk groups. Results: During the study period, 536 transports on ECMO were performed. The transport records could be identified in 514 of these cases (95.9%). In 163 (31.7%) transports 206 adverse events occurred. In 34 transports two or more adverse events passed on the same trip. No deaths occurred during transport. Sixty-five percent (134) of the complications were Patient related; the most prominent was loss of tidal volume with or without fluid flooding of the lung (n = 57, 43%). Lack of control of equipment was the most common Staff related flaw. Causes due to Equipment/technical (n = 30) could be traced to 14.6% of the events. Vehicle/transportation related complications were reported from 26 transfers, a sub-group in which 50% of the reports concerned malfunction of Ambulance utility/electrical, or Wrong ambulance size at hospital or airport. Conclusions: If transporting on ECMO high-risk or sudden threat-of-life situations are inevitable and have to be dealt with immediately, sometimes within seconds. A well-trained staff and an experienced high-volume organization are recommended. Key words: extra corporeal membrane oxygenation; ECMO, transport; adverse event; complication

Whole-lung lavage complicated with pneumothorax: a case report.

A patient with pulmonary alveolar proteinosis underwent whole lung lavage of the right lung. Lavage of the left lung was not immediately possible because of severe hypoxemia. Three days later, after correction of hypoxemia, we re-attempted the left lung lavage. However, the patient had severe hypoxemia (SpO2 < 80%) within a few minutes of performing right one lung ventilation (OLV). On bronchoscopic examination, proper tube location was confirmed. Bronchodilator nebulization and steroid injection were attempted with no effect. While searching for the cause of the hypoxemia, we found that the breath sound from the right lung had become very weak and distant compared with that from initial auscultation. Right pneumothorax was diagnosed on chest X-ray and a chest tube was inserted. After confirming pneumothorax resolution, we re-tried right OLV and were able to proceed with the left lung lavage without signs of aggravating air leak, loss of tidal volume, or severe hypoxemia.

Can ventilator settings reduce the negative effects of endotracheal suctioning? Investigations in a mechanical lung model.

BackgroundThe insertion of suction devices through endotracheal tubes (ETTs) increases airway resistance and the subsequent suctioning may reduce airway pressures and facilitate atelectasis.The aim of this study was to investigate how airway pressures and tidal volumes change when different combinations of suction equipment and ETT sizes are used, and to what extent unfavorable effects can be ameliorated by choice of ventilator settings.MethodsA mechanical ventilator was connected to a lung model by ETTs of 9 mm, 8 mm or 7 mm internal diameter (ID) with a pressure transducer inserted distal to the ETT. The effects of suction procedures with bronchoscope and closed catheter systems were investigated during pressure controlled ventilation (PCV) and volume controlled ventilation (VCV). In each mode, the effects of changes in inspiration:expiration (I:E) ratio, trigger sensitivity and suction pressure were examined.ResultsThe variables that contributed most to negative model airway pressures and loss of tidal volume during suctioning were (in descending order); 1) Small-size ETTs (7–8 mm ID) combined with large diameter suction devices (14–16 Fr); 2) inverse I:E ratio ventilation (in VCV); 3) negative ventilator trigger sensitivity; and 4) strong suction pressure. The pressure changes observed distal to the ETTs were not identical to those detected by the ventilator.ConclusionsNegative model airway pressure was induced by suctioning through small-size ETTs. The most extreme pressure and volume changes were ameliorated when conventional ventilator settings were used, such as PCV mode with short inspiration time and a trigger function sensitive to flow changes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12871-016-0196-z) contains supplementary material, which is available to authorized users.

Complications with the use of Bivona adjustable flange tracheostomy tube.

We wish to report two issues that we recently identified following the insertion of a Bivona (Smiths Medical, Ashford, UK) tracheostomy tube which developed recurrent leakage due to cuff deflation. In the first instance, the pilot balloon and cuff were both slowly deflating and required repeated re-inflation. In the second instance (with the same tube), the pilot balloon pressure was elevated, but the cuff continued to have a sizeable leak. On removal and examination of the tube, no structural damage was noted, but the cause for both incidents was identified. The Bivona tracheostomy tube was surgically inserted, and the cuff balloon was initially inflated with air and a good seal was achieved. However, we found a gradual and consistent loss of cuff pressure leading to a loss of tidal volume. The cuff was then re-inflated with air via the pilot balloon and although this resolved the issue temporarily, the cuff leak recurred and the cuff pressure was checked and indicated to be less than 20 cmH2O. Assuming this could be due to tube migration, the adjustable flange clip was released and the tube was inserted 1 cm further down the stoma site and the clip was reconnected to its position. The cuff was inflated with air; however, this manoeuvre did not resolve the issue of air leak; examination of the cuff pressure showed a pressure of between 80 and 90 cmH2O. The Bivona tracheostomy tube was changed to a conventional size 9.0 Portex (Smiths Medical, Ashford, UK) tube and ventilation improved. Following the removal of the Bivona tracheostomy tube, we had a thorough examination of the tube and found no structural defect or damage to the tube. However, we did find the reasons for the initial cuff leak and the unexpected high cuff pressure.

Endotracheal tube cuff leak: Minor product defect or lack of cuff pressure monitoring?

Sir, We report a leak in the pilot inflation line of an endotracheal tube (ETT) resulting in partial loss of tidal volume and increased risk of pulmonary aspiration. It also brings out the significance of intra-operative cuff pressure monitoring. A 60-year-old man, body mass index 30 kg/m2, a case of acute subdural hematoma and subarachnoid hemorrhage with increased intracranial pressure and deteriorating sensorium (Glasgow Coma Scale 6) was admitted to the intensive care unit. The history of preoperative fasting and other co-morbidities was unreliable. After a quick routine pre check for cuff patency of the ETT by inflation and cuff inspection followed by rapid deflation, the patient was intubated with a size 8.0 mm ID ETT (Ruschelit® Safety Clear Plus, Teleflex Medical Sdn Bhd, Kamunting, Malaysia) and the cuff was inflated with air and manually palpated to assess adequacy of its pressure. He was mechanically ventilated and other measures to control intracranial pressure were initiated. The patient was shifted to the operation theatre for an emergency craniotomy. Nitrous oxide and oxygen 60:40 sub-minimum alveolar concentration isoflurane and propofol infusion 50–100 μg/kg/min were used for maintenance. During the period of approximately 45 min from the time of intubation to the beginning of surgery, a loss of tidal volume was noticed. A check laryngoscopy ruled out tube migration. The cuff appeared lax and was re-inflated but the events repeated in the same manner again. The ETT was changed with another one and examined for obvious leaks. This ETT was then immersed in a bowl of water and the cuff inflated with an aneroid manometer (Mallinckrodt Medical Athlone, Ireland). Multiple air bubbles were noticed to appear at higher cuff pressures (>100 cm H2O), but as the pressure was reduced gradually, their size, number and speed lowered, and the bubbling stopped at the cuff pressure below 40 cm H2O. The leak was detected from the point where the transparent pilot inflation line entered the blue stem of the pilot cuff [shown by the arrow in [Figure 1]. The product defect was communicated to the manufacturers. Figure 1 Arrow showing air bubbles in water at higher cuff pressure; inset showing pilot inflation line entering the pilot cuff with the arrow showing the probable leak site A leak from any part of the ETT assembly can be alarming, more so in cases of difficult airway or in surgeries involving limited access to airway (non-supine position and head and neck surgery) where a change of tube may not be possible intra-operatively.[1] It may cause increased risk of pulmonary aspiration and inadequate ventilation (inadequate depth of anesthesia, intra-operative awareness, and hemodynamic instability). The leaks in the cuffs and the various ways to tackle them are well known but a defect in the pilot inflation line has been sparsely reported in the literature.[2] Various methods using continuous inflation with air, saline or lignocaine jelly or use of three-way stopcock to maintain cuff pressure are documented, though most of them are no more than a rescue measure.[1] This report alarms the caregiver to be vigilant at all times as even minor leaks from unusual sites may have clinically significant and long-standing consequences. Besides, it also reinforces the need for objective monitoring of the ETT cuff pressure, especially in the presence of nitrous oxide (which readily diffuses into the cuff and increases its pressure). Manual assessment of cuff pressure may be grossly incorrect and may underestimate pressures.[3] The pressure can be high as to manifest minor leaks (even when high volume low-pressure cuffs are used), as seen in the case reported. The effects of the leak due to the minor product defect could have been avoided if the cuff pressure was measured and maintained within the safe range of 20–30 cm of H2O.[4]

Early presentation of postintubation tracheoesophageal fistula: Perioperative anesthetic management

Tracheoesophageal fistula (TEF) in adults occurs as a result of trauma, malignancy, cuff-induced tracheal necrosis from prolonged mechanical ventilation, traumatic endotracheal intubation, foreign body ingestion, prolonged presence of rigid nasogastric tube, and surgical complication. Anesthetic management for repair of TEF is a challenge. Challenges include difficulties in oxygenation or ventilation resulting from placement of endotracheal tube in or above the fistula; large fistula defect causing loss of tidal volume with subsequent gastric dilatation, atelactasis, and maintenance of one lung ventilation. The most common cause of acquired nonmalignant TEF is postintubation fistula, which develops after prolonged intubation for ventilatory support. Acquired TEF, which occurs after prolonged intubation, usually develops after 12–200 days of mechanical ventilation, with a mean of 42 days. We present a rare case of TEF that developed after 7 days of intubation. It was a difficult case to be diagnosed as patient had a history of polytrauma, followed by emergency intubation and both these conditions can contribute to tracheobronchial injury.

The diagnostic challenge of a tracheal tear with a double-lumen endobronchial tube: massive air leak developing from the mouth during mechanical ventilation

The case of a 78 year-old woman who underwent a right lower lobectomy using a 35-French, left-sided, double-lumen endobronchial tube (DLET) is presented. Multiple adjustments were needed for the DLET's proper placement. At the end of surgery, sudden loss of tidal volume with a large air leak from the patient's mouth was noted. Fiberoptic bronchoscopic examination through the DLET was negative. Rupture of the tracheal cuff was suspected, and the DLET was replaced with a single-lumen tube. In the intensive care unit, the massive air leak from the mouth recurred during mechanical ventilation. Nasal fiberoptic bronchoscopic examination showed a longitudinal laceration of the membranous portion of the trachea extending from the subglottic area to the orifice of the right bronchus. Surgical repair of the tear was performed.

The intracorporeal use of 2-octyl cyanoacrylate resin to control air leaks after lung resection

To describe the outcome of patients who had 2-octyl cyanoacrylate used as an adjunct to control air leaks after lung resection by application directly onto the visceral pleura. A retrospective review of these patients from 2007 to 2009 from a single surgeon's practice. Seven challenging patients had 2-octyl cyanoacrylate used to control difficult air leaks after lung resection. The indications included lack of standard sealants in patients with emphysematous lung that would not hold suture and vast air leaks after decortications or extensive nonanatomic resections in patients that would not tolerate the loss of tidal volume. All air leaks sealed immediately and none of the patients left the operating theater with an air leak, including three patients who underwent difficult decortications for empyema. All patients recovered uneventfully, except one patient who died from acute respiratory distress syndrome. His postmortem examination revealed that the resin remained intact on the lung without signs of degradation after being in an intracorporeal environment for weeks. There were no complications nor toxicity directly related to the 2-octyl cyanoacrylate resin. 2-Octyl cyanoacrylate is extremely effective in immediately controlling air leaks, with the results being seen instantly. It dries quickly, does not wash off the lung, and remains intact on the visceral pleura for several weeks. 2-Octyl cyanoacrylate deserves additional testing as an adjunct to control air leaks after lung resection.

Perioperative use of cuffed endotracheal tubes is advantageous in young pediatric burn patients

Uncuffed endotracheal tubes traditionally have been preferred over cuffed endotracheal tubes in young pediatric patients. However, recent evidence in elective pediatric surgical populations suggests otherwise. Because young pediatric burn patients can pose unique airway and ventilation challenges, we reviewed adverse events associated with the perioperative use of cuffed and uncuffed endotracheal tubes. We retrospectively reviewed 327 cases of operating room endotracheal intubation for general anesthesia in burned children 0–10 years of age over a 10-year period. Clinical airway outcomes were compared using multivariable logistic regression, controlling for relevant patient and injury characteristics. Compared to those receiving cuffed tubes, children receiving uncuffed tubes were significantly more likely to demonstrate clinically significant loss of tidal volume (odds ratio 10.62, 95% confidence interval 2.2–50.5) and require immediate reintubation to change tube size/type (odds ratio 5.54, 95% confidence interval 2.1–13.6). No significant differences were noted for rates of post-extubation stridor. Our data suggest that operating room use of uncuffed endotracheal tubes in such patients is associated with increased rates of tidal volume loss and reintubation. Due to the frequent challenge of airway management in this population, strategies should emphasize cuffed endotracheal tube use that is associated with lower rates of airway manipulation.

Use of the pro-seal laryngeal mask airway facilitates percutaneous dilatational tracheostomy in an intensive care unit

Purpose:To study the feasibility of using the pro-seal laryngeal mask airway (LMA) for airway maintenance during bronchoscopic-guided percutaneous tracheostomy.Materials and Methods:Observational study of 60 patients in a 16-bed intensive care unit. The patient’s tracheal tube was exchanged for a pro-seal LMA before undertaking percutaneous tracheostomy.Results:Inspiratory pressure and tidal volumes achieved during the procedure were recorded. The median peak inspiratory pressure was 25 (standard deviation 4.4) cm H2O. There was no loss of tidal volume in 30 patients, a loss of less than 100 mL/breath in 27, and loss of more than 100 mL in 3 patients. A pro-seal LMA successfully maintained the airway and allowed adequate ventilation during per-cutaneous tracheostomy in all 60 patients. In all patients, fiber optic bronchoscopy through the pro-seal LMA provided a clear view of the cords and trachea and there was no laryngeal or tracheal soiling at any stage of the procedure.Conclusion:The pro-seal LMA provides a reliable airway and allows effective ventilation during percutaneous tracheostomy. The passage of a fiberscope through the pro-seal LMA and glottis is easy and provides a clear view of the upper trachea.

Percutaneous Tracheostomy in ICU

Dear Editor, We read with interest the recent article of Yavas on the tracheostomy in the intensive care unit.1 The authors treated 205 patients needing tracheostomy, 65.4% with surgical tracheostomy (ST) and 34.6% with percutaneous tracheostomy (PT). The authors, while performing PT, used two procedures: the Ciaglia percutaneous dilatational tracheostomy technique using multiple dilators and the Griggs percutaneous technique using guidewire-dilating forceps. We would like to address two points on the use of PT. First point: Since the first report,2 the technique has undergone an important modification: a single dilator has been substituted for multiple dilators. This is a bevelled and curved dilator for the Blue Rhino and the UltraPerc technique and a screwlike dilating device for the Percu-twist technique described by Frova and Quintel.3 The single-step dilator has the advantage of not requiring a change in dilator, thereby reducing tidal volume loss until the tracheostomy tube is inserted and reducing the bleeding during the changing of dilators. The Percutwist kit3 has a screw-type dilator with a hydrophilic coating activated by wetting; this dilator has a thin internal lumen and the guidewire slides into that. The dilator is advanced over the guidewire to the skin and is rotated clockwise into the soft tissue, avoiding pressure over the anterior tracheal wall. Second point: The procedure can be performed under bronchoscopic guidance to confirm the correct site for puncture that is spotted with tracheal transillumination. After the correct site of needle is confirmed by bronchoscopy, the metal needle is removed and a Seldinger guidewire is advanced into the trachea through the cannula.

Recovery from welding-fume-exposure-induced lung fibrosis and pulmonary function changes in sprague dawley rats.

Welder's pneumoconiosis has generally been determined as benign based on the absence of pulmonary function abnormalities in welders with marked radiographic abnormalities. Yet, there have also been several reports on welders with respiratory symptoms, indicating lung function impairment, X-ray abnormalities, and extensive fibrosis. Accordingly, this study attempted to investigate the inflammatory responses and pulmonary function changes in rats during a 60-day welding-fume-inhalation exposure period to elucidate the process of fibrosis. The rats were exposed to manual metal-arc stainless-steel welding fumes (MMA-SS) with total suspended particulate concentrations of 64.8 +/- 0.9 (low dose) and 107.8 +/- 2.6 mg/m3 (high dose) for 2 h per day in an inhalation chamber for 60 days. Animals were sacrificed after the initial 2-h exposure and after 15, 30, and 60 days, and the pulmonary function was also measured every week after the daily exposure. Elevated cellular differential counts were also measured in the acellular bronchoalveolar lavage fluid of the rats exposed to the MMA-SS fumes for 60 days. Among the pulmonary function test parameters, only the tidal volume showed a statistically significant and dose-dependent decrease after 35 to 60 days of MMA-SS welding-fume exposure. When the rats exposed to the welding fumes were left for 60 days to recover their lung function and cellular differentiation, recovery was observed in both the high and low-dose rats exposed up to 30 days, resulting in the disappearance of inflammatory cells and restoration of the tidal volume. The rats exposed for 60 days at the low dose also recovered from the inflammation and tidal volume loss, yet the rats exposed for 60 days at the high dose did not fully recover even after a 60-day recovery period. Therefore, when taken together, the results of the current study suggest that a decrease in the tidal volume could be used as an early indicator of pulmonary fibrosis induced by welding-fume exposure in Sprague Dawley rats, and fibrosis would seem to be preventable if the exposure is short-term and moderate.

A new ventilator converter with the Siemens Servo Ventilator--evaluation in a lung model.

A ventilator converter device (Anmedic) for connecting a non-rebreathing ventilator (Servo Ventilator 900 B; Siemens-Elema) to a circle anaesthesia system was evaluated in a lung model. Recorded minute ventilation was slightly lower than dialled in most cases. We furthermore found inadequate expiratory expansion of the ventilator converter bellows, with progressive loss of tidal volume and consequently recorded minute volume, when fresh gas flow to the circle system was low (1 l.min-1), expiratory time was short (less than 40%) and respiratory obstruction was present.