Sang Beom Nam

Incidence and Risk Factors of Acute Kidney Injury After Thoracic Aortic Surgery for Acute Dissection

BACKGROUND Previous studies have reported a high incidence of acute kidney injury (AKI) after thoracic aortic surgery in heterogeneous patient cohorts, including various aortic diseases and the use of deep hypothermic circulatory arrest. Moderate hypothermia with cerebral perfusion makes deep hypothermia nonessential, but can make end organs susceptible to ischemia during circulatory arrest. We investigated the incidence and risk factors of AKI after thoracic aortic surgery with and without moderate hypothermic circulatory arrest for acute dissection. METHODS We reviewed the medical records of 98 patients undergoing graft replacement of the thoracic aorta for acute dissection between 2008 and 2011 at a university hospital. Acute kidney injury was defined by RIFLE criteria, which is based on serum creatinine or glomerular filtration rate. RESULTS The mean age was 55±15 years. The surgical procedures, 96% of which were emergencies, involved the ascending aorta (67%), aortic arch (41%), descending aorta (41%), and aortic valve (5%). Moderate hypothermic circulatory arrest was performed in 75%. The overall incidence of AKI was 54%, and 11% of 98 patients required renal replacement therapy. Thirty-day mortality increased with AKI severity (p=0.002). Independent risk factors for AKI were long cardiopulmonary bypass duration (>180 minutes; odds ratio, 7.50; p=0.008) and preoperative serum creatinine level (odds ratio, 8.43; p=0.016). CONCLUSIONS Acute kidney injury was common after thoracic aortic surgery for acute dissection with or without moderate hypothermic circulatory arrest and worsened 30-day mortality. Prolonged cardiopulmonary bypass and increased preoperative serum creatinine were independent risk factors for AKI, but moderate hypothermic circulatory arrest was not.

The usefulness of the laryngeal mask airway Fastrach for laryngeal surgery.

Background and objective Suspension laryngoscopy under general anaesthesia with a tracheal tube has been widely used for laryngeal microsurgery, but it has some limitations such as intense cardiovascular stimulation during anaesthesia of short duration, occasionally a poor surgical field, and the possibility of a mass being hampered by the tracheal tube. The aim of this study was to compare the usefulness of the laryngeal mask airway (LMA) Fastrach and fibreoptic bronchoscope with a conventional suspension laryngoscope in laryngeal microsurgery. Methods Forty patients scheduled for laryngeal microsurgery were enrolled in this prospective randomized study consecutively. After general anaesthesia was induced, laryngeal microsurgery was performed with a fibreoptic bronchoscope through the LMA Fastrach or conventional suspension laryngoscope. The best view of the surgical field, evaluated by percentage of glottic opening score, was obtained by the up–down manipulations of the LMA Fastrach or repositioning the suspension laryngoscope. Blood pressure and heart rate changes at the baseline, preinsertion, and postinsertion were recorded. Results Percentage of glottic opening score of the LMA Fastrach group was 100 and that of the suspension laryngoscope group was 80 (P < 0.05). The LMA Fastrach insertion was performed without remarkable systolic or diastolic blood pressure or heart rate changes, but systolic, diastolic blood pressure or heart rate were increased after intubation in the suspension laryngoscope group. Conclusion The LMA Fastrach during fibreoptic bronchoscope-guided laryngeal surgery provided a good surgical field and haemodynamic stability without additional risk compared with the conventional suspension laryngoscope.

The CobraPLA™ during anesthesia with controlled ventilation: A clinical trial of efficacy

The CobraPLA™ (CPLA) is a relatively new supraglottic airway device that has not been sufficiently investigated. Here, we performed a prospective observational study to evaluate the efficacy of the CPLA during controlled ventilation. In 50 anesthetized and paralyzed patients undergoing elective surgery a CPLA was inserted and inflated to an intracuff pressure of 60 cm H2O. The success rate of insertion upon the first attempt was 82% (41/50), with a mean insertion time of 16.3 ± 4.5 seconds. The adequacy of ventilation was assessed by observing the end tidal CO2 waveform, movement of the chest wall, peak airway pressure (13.5 cm H2O), and leak fraction (4%). We documented the airway sealing pressure (22.5 cm H2O) and noted that the the site of gas leaks at that pressure were either at the neck (52%), the abdomen (46%), or both (2%). In 44 (88%) patients, the vocal cords were visible in the fiberoptic view through the CPLA. There was no gastric insufflation during the anesthesia. Respiratory and hemodynamic parameters remained stable during CPLA insertion. Postoperative blood staining of CPLA was minimal, occurring in 22% (11/50) of patients. Mild and moderate throat soreness was reported in 44% (22/50) and 4% (2/50) of patients, respectively. Lastly, mild dysphonia was observed in 6% (3/50) of patients and mild dysphagia in 10% (5/50) of patients. Our results indicated that the CPLA is both easy to place and allows adequate ventilation during controlled ventilation.

Stress-induced cardiomyopathy after negative pressure pulmonary edema during emergence from anesthesia -A case report-

Stress-induced cardiomyopathy (SICM) presenting as an acute myocardial dysfunction is characterized by transient left ventricular wall motion abnormality, which has been known to be associated with excessive catecholamine production caused due to various types of stress. Sympathetic hyperactivity is common during the perioperative period, and reports of SICM occurring during this period have actually increased. We present a case of SICM following negative pressure pulmonary edema due to upper airway obstruction during emergence from anesthesia. Excessive catecholamine release in response to respiratory difficulty could have been the underlying inciting factor.

Relationship between arterial and end‐tidal carbon dioxide pressures during anesthesia using a laryngeal tube

Background:  The Laryngeal Tube® (LT), (VBM Medizintechnik, Sulz, Germany) is a relatively new supraglottic device for controlling the airway. Arterial carbon dioxide tension (PaCO2) can be estimated by monitoring the end‐tidal tension of carbon dioxide (PETCO2). The relationship between PETCO2 and PaCO2 during controlled ventilation via the LT has not been reported.

Comparison of the i-gel and other supraglottic airways in adult manikin studies: Systematic review and meta-analysis

Background: The i-gel has a gel-like cuff composed of thermoplastic elastomer that does not require cuff inflation. As the elimination of cuff inflation may shorten insertion time, the i-gel might be a useful tool in emergency situations requiring prompt airway care. This systematic review and meta-analysis of previous adult manikin studies for inexperienced personnel was performed to compare the i-gel with other supraglottic airways. Methods: We searched PubMed, the Cochrane Library, and EMBASE for eligible randomized controlled trials (RCTs) published before June 2015, including with a crossover design, using the following search terms: “i-gel,” “igel,” “simulation,” “manikin,” “manikins,” “mannequin,” and “mannequins.” The primary outcomes of this review were device insertion time and the first-attempt success rate of insertion. Results: A total of 14 RCTs were included. At the initial assessment without difficult circumstances, the i-gel had a significantly shorter insertion time than the LMA Classic, LMA Fastrach, LMA Proseal, LMA Unique, laryngeal tube, Combitube, and EasyTube. However, a faster insertion time of the i-gel was not observed in comparisons with the LMA Supreme, aura-i, and air-Q. In addition, the i-gel did not show the better results for the insertion success rate when compared to other devices. Conclusion: The findings of this meta-analysis indicated that inexperienced volunteers placed the i-gel more rapidly than other supraglottic airways with the exception of the LMA Supreme, aura-i, and air-Q in manikin studies. However, the quicker insertion time is clinically not relevant. The unapparent advantage regarding the insertion success rate and the inherent limitations of the simulation setting indicated that additional evidence is necessary to confirm these advantages of the i-gel in an emergency setting.

Hypoglossal nerve injury following the use of the CobraPLA.

EDITOR: Hypoglossal nerve injury has been reported as a complication associated with airway management using supraglottic airways [1–5]. The CobraPLA (CPLA) is a relatively new supraglottic airway device. There is no report of cranial nerve injury following the use of the CPLA. We present a case of hypoglossal nerve injury after the use of the CPLA. A healthy 51-yr-old male, height 177 cm, weight 80 kg, was scheduled for elective orthopaedic surgery for ulnar nerve palsy after right supracondylar fracture. He had no past medical history. His preanaesthetic physical examination was normal. Midazolam 3.0 mg and glycopyrrolate 0.2 mg was given intravenously for premedication. Anaesthesia was induced with propofol 100 mg and rocuronium 50 mg. A CPLA, size 4, was inserted successfully on the first attempt without difficulty. The cuff was inflated with air by using a manometer (Cuff Pressure Gauge; VBM Medizintechnik, Sulz, Germany) to a pressure of 60 cm H2O. Anaesthesia was maintained with enflurane, air and oxygen. We monitored cuff pressure continuously and kept the pressure between 60 and 70 cm H2O throughout the operation. The patient’s head was placed in the neutral position during the operation. The operation was uneventful and lasted 2 h 55 min. After the patient was awakened, the CPLA cuff was deflated and expelled. There was no blood on the surface of the cuff. After discharge from the recovery room, the patient complained of a strange feeling in his tongue and some impairment of speech. On the day after the operation, his tongue deviated to the right on protrusion. Swelling was observed on the right side of the tongue. Neurological examination was otherwise normal. Diagnosis of an isolated right hypoglossal nerve injury was made. Dexamethasone 10 mg was given followed by prednisolone 60 mg day. After 7 days, deviation of the tongue was much improved. After 12 days, he was discharged with only a slight deviation remaining. He was scheduled for outpatient follow-up. The use of supraglottic airway is increasing and with it the number of complications. Supraglottic airways are relatively atraumatic, but any manipulation of the oropharyngeal cavity might lead to injury of any related structure contained therein. Hypoglossal nerve injury is a rare complication of airway manipulation using a supraglottic airway. It may be injured, alone or in combination with the lingual nerve and/or recurrent laryngeal nerve. Many cases are related to the use of N2O, the position of the patient during the operation or the preexisting disease [1–5]. Excessive cuff pressure or malposition of cuff is likely to have played a part. In this case, we did not use N2O, and monitored and kept the cuff pressure below 70 cm H2O continuously. The head was placed neutrally without fixation. The position of the CPLA had no problem clinically, but we cannot rule out the possibility of an improper position of the tongue. Also, we think that the operation time was relatively long. Even when a patient is healthy, N2O is not used, and the patient is placed neutrally; prolongation of the operation might increase the risk of nerve injury in patients using the CPLA.

The use of the LMA Fastrach™ system as a guidance tool for inaccessible glottic lesion biopsies

Sir, Laryngeal microsurgery (LMS) for vocal cord lesions is usually performed using a suspension laryngoscope. However, some lesions cannot be accessed using this method. We report the use of the LMA Fastrach airway system (ILMA; LMA North America Inc., San Diego, CA) as a guidance tool in a case of an inaccessible glottic lesion. A 66-year-old, 62 kg male patient was referred to our hospital for biopsy of a vocal cord mass that could not be visualized under suspension laryngoscopy at facilities previously visited by the

Standard versus Rotation Technique for Insertion of Supraglottic Airway Devices: Systematic Review and Meta-Analysis

Purpose Supraglottic airway devices have been widely utilized as an alternative to tracheal intubation in various clinical situations. The rotation technique has been proposed to improve the insertion success rate of supraglottic airways. However, the clinical efficacy of this technique remains uncertain as previous results have been inconsistent, depending on the variable evaluated. Materials and Methods We systematically searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials in April 2015 for randomized controlled trials that compared the rotation and standard techniques for inserting supraglottic airways. Results Thirteen randomized controlled trials (1505 patients, 753 with the rotation technique) were included. The success rate at the first attempt was significantly higher with the rotation technique than with the standard technique [relative risk (RR): 1.13; 95% confidence interval (CI): 1.05 to 1.23; p=0.002]. The rotation technique provided significantly higher overall success rates (RR: 1.06; 95% CI: 1.04 to 1.09; p<0.001). Device insertion was completed faster with the rotation technique (mean difference: -4.6 seconds; 95% CI: -7.37 to -1.74; p=0.002). The incidence of blood staining on the removed device (RR: 0.36; 95% CI: 0.27 to 0.47; p<0.001) was significantly lower with the rotation technique. Conclusion The rotation technique provided higher first-attempt and overall success rates, faster insertion, and a lower incidence of blood on the removed device, reflecting less mucosal trauma. Thus, it may be considered as an alternative to the standard technique when predicting or encountering difficulty in inserting supraglottic airways.

Thrombus entrapped by patent foramen ovale in a patient with pulmonary embolism: a case report

Thrombus-in-transit appears to increase the risk of mortality compared to pulmonary embolism alone and can require alteration in therapeutic plan. We present the case of a biatrial thromboembolus caught in transit across a patent foramen ovale diagnosed by intraoperative transesophageal echocardiogram in a 69-year-old female with acute pulmonary embolism and subsequent acute cerebral infarction. We suggest that echocardiography should be performed in a patient with suspected pulmonary thromboembolism to evaluate right heart function and diagnose emboli in transit.