Gastric Tube Insertion Performance of Second-Generation Supraglottic Airway Devices: A Prospective Manikin Study With Literature Review

BACKGROUND

Second-generation supraglottic airway devices (SGAs) are pivotal in airway management, with the ability to accommodate gastric tube (GT) insertion. However, research on GT insertion with SGAs under controlled conditions is limited. This study aimed to evaluate the GT insertion performance of SGAs using a manikin.

METHODS

This prospective study included 32 anesthesiologists in our department, each with more than two years of clinical experience. These anesthesiologists randomly inserted four second-generation SGAs, including i-gel (Intersurgical Ltd., Berkshire, UK), Ambu AuraGain (Ambu, Copenhagen, Denmark), LMA ProSeal (Teleflex Medical, Wayne, PA), and LMA Supreme (Teleflex Medical), all of size 4, into a manikin, followed by GT insertion using Salem Sump™ tubes (Cardinal Health, Dublin, OH) (12 Fr for i-gel and 14 Fr for others) until the GT was 55 cm deep at the port entrance. The primary outcome was the difference in GT insertion time, with participants' evaluations. The usual use of second-generation SGAs, including GT insertion, was also surveyed. The differences in GT insertion time among the four SGAs were analyzed using the Friedman test, followed by the Bonferroni method for post-hoc analysis. P < 0.05 was considered significant.

RESULTS

The median GT insertion times were 17.2 seconds for i-gel, 9.9 seconds for AuraGain, 18.8 seconds for ProSeal, and 8.9 seconds for Supreme. These times showed significant differences (p < 0.001). Post-hoc analysis revealed that both Supreme and AuraGain had significantly shorter insertion times than i-gel and ProSeal, respectively (p < 0.001). Of the participants, 59% (19/32) evaluated Supreme as the easiest SGA for GT insertion, which is consistent with the observed insertion times. i-gel was the most frequently used SGA, chosen by 72% (23/32) of participants. Additionally, 72% (23/32) of anesthesiologists inserted GTs less than half as often following second-generation SGA placement.

CONCLUSIONS

Significant differences in GT insertion performance were found among the four second-generation SGAs. According to a survey of participants, second-generation SGAs were often used without GT insertion. Although the differences between products may not be clinically significant, selecting an SGA with easy GT insertion may improve the efficiency and reliability of gastric content drainage and enhance the safety of airway management when using SGAs.

Required volume for color flow injection test to confirm the intravascular placement of a peripheral venous catheter

BACKGROUND

Confirmation of adequate peripheral intravenous catheter placement is essential before using venous catheters. The color flow injection test has been reported as a method with high sensitivity and specificity for this purpose. The technique involves administrating saline through the peripheral venous route to observe changes in the color flow pattern around the same vein at a more central location. However, the required volume of saline remains uncertain. This study aims to determine the appropriate dosage for conducting the test in pediatric patients and explore any potential correlations between dosage and patient characteristics.

METHODS

A prospective study was conducted in children under 6 years of age with American Society of Anesthesiologists Physical Status 1-2 presenting for general anesthesia. After an intravenous cannula was placed in the forearm under general anesthesia, normal saline was injected at a speed of approximately 1 mL/s while the axillary artery and vein were observed with color flow Doppler imaging. The volume of normal saline required to induce a change in the color flow pattern around the vessels was measured. Measurements were performed twice and averaged for comparison with patient characteristics and other factors.

RESULTS

The study cohort included 30 patients aged from 0.3 to 5.5 (2.6 ± 1.6) years. The change in color flow Doppler imaging was noted in all the patients, and the average volume was 1.40 ± 0.36 mL (95% confidence interval (CI), 1.27-1.54; p < 0.001), which was significantly correlated with age, with a correlation coefficient of 0.435 (95% CI, 0.09-0.69; p = 0.02).

CONCLUSIONS

The required volume for the color flow injection test is small; therefore, the test is easy to perform and minimally invasive in pediatric patients.

One-lung ventilation and 3D image analysis in a case of tracheal bronchus with steeply angled branching of left main bronchus: a case report

Background

Establishing one-lung ventilation (OLV) in patients with tracheal bronchus (TB) may be challenging due to its unusual bronchial anatomy. We present a case of difficult OLV in a patient with right TB and steeply angled bifurcation of the left main bronchus.

Case presentation

A 79-year-old woman was scheduled to undergo video-assisted thoracic surgery left upper lobectomy. We planned right OLV with a bronchial blocker; however, it was difficult to place the blocker in the left main bronchus due to a steep bifurcation angle. Therefore, we changed the entry angle of the lumen tip by advancing the tracheal tube to just above the tracheal bifurcation, allowing successful placement of the bronchial blocker into the bronchus.

Conclusion

For airway management in patients with TB, especially for OLV, it is essential to understand the anatomy of the trachea, bronchus, and TB and to select the appropriate device for each case.

Usefulness of real-time elastography for diagnosing lymph node metastasis of skin cancer: does elastography potentially eliminate the need for sentinel lymph node biopsy in squamous cell carcinoma?

BACKGROUND

The metastatic involvement of regional lymph nodes is the most important prognostic factor for overall survival of skin cancer patients. The sonographic technique of freehand real-time tissue elastography (RTE), which displays tissue rigidity as a colour overlay of the tissue image, was developed.

OBJECTIVE

Our purpose was to evaluate the benefit of RTE for detecting lymph node metastases of skin cancer non-invasively before operation.

METHODS

We first selected lymph nodes of skin cancer patients which had already been diagnosed by biopsy as being reactive or metastatic, and then retrospectively collected images of RTE and B-mode and colour Doppler ultrasound on those lymph nodes performed preoperatively. Twenty-one lymph nodes from 12 patients with squamous cell carcinoma (SCC), 23 lymph nodes from 14 patients with malignant melanoma (MM) and 14 lymph nodes from six patients with extramammary Paget disease (Paget) were investigated. Elastographic images were assessed on a scale of one to four according to the percentage of high elasticity (hard) area (HEA) in the lymph node.

RESULTS

In all three skin cancers, lymph nodes evaluated as grade 3 or 4 by RTE were metastatic. All lymph nodes evaluated as grade 1 or 2 by RTE were reactive in SCC, whereas some lymph nodes evaluated as grade 1 or 2 were metastatic in MM and Paget.

CONCLUSION

Real-time tissue elastography may aid in distinguishing reactive lymph nodes from metastatic ones especially in SCC.

Intracuff pressure during one-lung ventilation in infants and children

OBJECTIVE

We prospectively evaluated intracuff pressure (IP) during one-lung ventilation (OLV) to characterize potential risk associated with overinflation of the cuff used for OLV.

DESIGN

Prospective observational study over a 2-year period, in infants and children undergoing thoracic surgery. The IPs of the tracheal and bronchial balloon were measured using a manometer and compared to a previously recommended threshold of 30 cmH2O. Data were compared by the device type used to achieve OLV.

SETTING

Freestanding tertiary-care pediatric hospital.

PARTICIPANTS

Patients ≤18 years of age undergoing thoracic procedures requiring OLV.

INTERVENTIONS

Measurement of IP.

MEASUREMENTS AND MAIN RESULTS

Thirty patients were enrolled (age 5 months-18 years) with a median weight of 28 kg. Median tracheal and bronchial IPs were 32 cmH2O (range: 11, 90) and 44 cmH2O (range: 10, 100), respectively. The tracheal and bronchial IPs exceeded 30 cmH2O in 13 of 20 patients (65%) and 21 of 30 patients (70%), respectively.

CONCLUSIONS

IP was high and in excess of recommended levels in most children undergoing OLV. Continuous monitoring of IP may be indicated during OLV to address the risks involved and ensure the prevention of complications related to high IP.

TYPE OF STUDY

Prospective comparative study.

LEVEL OF EVIDENCE

Level II.

Changes in cerebral and renal oxygenation during laparoscopic pyloromyotomy

Although a laparoscopic approach may be preferred over open procedures for abdominal surgery, there are limited data on the effect of laparoscopic procedures on cerebral and renal oxygenation in neonates and young infants. Here, we evaluated the effect in neonates and infants. In this two-center prospective observational study, we evaluated changes in cerebral and renal regional oxygen saturation (rSO₂) in infants during laparoscopic pyloromyotomy. Intraoperative hemodynamic and respiratory parameters and rSO₂ were recorded. For the primary outcome, these parameters were compared at incision and at the end of pneumoperitoneum. The study cohort included 25 infants with a mean age of 40 ± 10 days and weight of 4.0 ± 0.6 kg. IAP at the beginning of laparoscopy was 10 ± 2 mmHg (range 7-15 mmHg). Although both cerebral and renal rSO₂ decreased from incision compared to the end of laparoscopy, the decrease reached statistical significance only for cerebral rSO₂ (81 ± 12 to 76 ± 16, p = 0.033). Similarly, the increase in fractional tissue oxygen extraction (FTOE) was only statistically significant for cerebral FTOE (0.18 ± 0.12 to 0.23 ± 0.16, p = 0.037). No change in hemodynamic or respiratory parameters was found. Although there was a decrease in cerebral rSO₂ and increase in cerebral FTOE during pneumoperitoneum, the values did not decrease below those noted before anesthetic induction.

Use of remifentanil in general anesthesia for neonatal non-cardiac surgery: a case series

OBJECTIVE

This case series aimed to summarize our experience in usage of remifentanil in neonates undergoing non-cardiac surgery.

BACKGROUND

Physiology of neonates and infants is different from that of adults. Immaturity of their vital organ systems narrows a safety margin of perioperative management including anesthesia. Remifentanil has favorable characteristics for pediatrics such as short duration of action and rapid elimination. Although remifentanil was introduced into clinical practice since 1996, its application to neonatal anesthesia has not been validated yet.

METHODS

This is a 14-month retrospective case series of neonates receiving remifentanil during non-cardiac surgery at a tertiary care pediatric hospital in Japan. Patients' characteristics, intraoperative data, and complications were retrieved from medical records.

RESULTS

A total of 68 neonates underwent non-cardiac surgery under general anesthesia, of whom 48 received remifentanil. Infusion rate was 0.14 (0.04-0.35) mcg/kg/min (median, range). No intractable adverse events including postoperative apnea were detected.

CONCLUSION

Remifentanil is generally feasible to neonatal surgical population.

General anesthesia with a native airway for patients with mucopolysaccharidosis type III

BACKGROUND

Mucopolysaccharidosis type III is a progressive disease with worsening airway, pulmonary, and cardiac involvement that may complicate anesthetic care.

AIM

To prospectively evaluate the incidence of airway issues and complications during magnetic resonance imaging (MRI) and lumbar puncture (LP) during general anesthesia with a native airway for patients with mucopolysaccharidosis type III.

METHOD

The study was a part of the natural history study. Anesthesia was induced with sevoflurane, which was discontinued after intravenous access was obtained. General anesthesia with a native airway was provided by dexmedetomidine and propofol. Dexmedetomidine (0.5 μg·kg^-1 ) was administered over 5 min followed by a continuous infusion at 0.5 μg·kg^-1 ·h^-1 . A continuous infusion of propofol was started at 150 μg·kg^-1 ·min^-1 . A bolus dose of propofol (1 mg·kg^-1 ) was administered and the propofol infusion was increased as needed. Airway management and vital signs were recorded for the entire procedure until discharge.

RESULTS

Twenty-five patients (6.9 ± 3.1 years) received total of 43 MRI and LP procedures in the cohort. No patient failed sedation. Although mask induction with sevoflurane was not clinically problematic, upper airway obstruction was noted during 14 procedures (33%). This required the application of continuous positive airway pressure, temporary oral airway placement, jaw thrust, or shoulder roll. Airway dynamics improved once the anesthesia was transitioned to intravenous anesthetic agents. Although a small shoulder roll was needed to improve airway patency for 11 cases (26%), a large shoulder roll tended to make the upper airway obstruction worse. Oxygen desaturation (≤90%) was noted during MRI in three cases (7%).

CONCLUSION

A combination of dexmedetomidine and propofol provided effective general anesthesia with a native airway during the procedures. Although upper airway obstruction was noted, it resolved with simple airway maneuvers without further airway intervention.

Perioperative care in an adolescent patient with heparin-induced thrombocytopenia for placement of a cardiac assist device and heart transplantation: case report and literature review

Heparin-induced thrombocytopenia (HIT) can cause life-threatening complications following the administration of heparin. Discontinuation of all sources of heparin exposure and the use of alternative agents for anticoagulation are necessary when HIT is suspected or diagnosed. We present the successful use of bivalirudin anticoagulation in an adolescent patient during cardiopulmonary bypass who underwent both placement of a left ventricular assist device and subsequent heart transplantation within a 36-hour period. The pathophysiology and diagnosis of HIT are reviewed, previous reports of the use of direct thrombin inhibitors for cardiac surgery are presented, and potential dosing regimens for bivalirudin are discussed.

A Retrospective Analysis of the Influence of Ventricular Morphology on the Perioperative Outcomes After Fontan Surgery

OBJECTIVES

The objectives of this study were to evaluate the effect of ventricular morphology on perioperative outcomes during Fontan surgery.

DESIGN

Retrospective cohort study.

SETTING

Single standing, not-for-profit pediatric hospital.

PARTICIPANTS

A total of 72 patients who underwent Fontan surgery using cardiopulmonary bypass without aortic cross-clamp between January 1, 2009 and December 31, 2014.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The patients were divided into 3 categories depending on their single-ventricle lesions: (1) LV group (n = 20): left dominant and hypoplastic right ventricle; (2) RV group (n = 37): right dominant and hypoplastic left ventricle; and (3) BV group (n = 15): biventricular or indeterminate dominance. Perioperative major adverse events were collected based on the Society of Thoracic Surgeons database. The need for perioperative allogeneic blood transfusions also was determined. The mean age was 3.3±1.7 years and the mean weight was 13.6±4.0 kg. All patients had extracardiac lateral tunnel or conduit Fontan procedures. Sixty-nine of the patients (96%) underwent tracheal extubation in the operating room. Anesthesia, surgery, and CPB times were 326±68, 239±73, and 70±41 minutes, respectively. Eleven patients (15%) required allogeneic blood products intraoperatively, while 30 patients (42%) required allogeneic blood products during the perioperative period. Length of cardiac intensive care unit stay and hospital stay (median [IQR]) were 1 [1,2] and 12 [9,18] days, respectively. There was no mortality and no significant differences between groups in major postoperative complications, anesthetic or surgical variables.

CONCLUSIONS

No difference in the immediate perioperative outcomes was noted based on ventricular morphology.

[Laparoscopi Surgery and Anesthetic Management for Infants and Children]

The advantages of laparoscopic surgery resulting in quicker recovery from surgery, decreased postopera- tive pain, shorter hospital stay, and an: improved cos- metic outcome compared to open surgery have led to the expansion of its applications. This expansion includes its use for new surgical procedures as well as indications in younger patients even neonates. The majority of surgical procedures in children are at- tempted under laparoscopy, ranging from short pro- cedures such as day surgeries to even longer case such as congenital biliary atresia. The anesthetic man- agement of laparoscopic surgery in pediatric population has unique features and pitfalls. This chapter de- scribes : (i) the application of laparoscopic surgery for pediatrics ; (ii) the physiological effects of pneumo- peritoneum on respiratory, cardiovascular, renal sys- tems and intracranial pressure ; and (iii) actual anes- thesia management To accomplish safe anesthetic management of the pediatric patients for laparoscopic surgery, anesthesiologists should be familiar with the basic tenets of pediatric anesthesia as well as the potential physiological changes that result from in- creased intra-abdominal pressure due to insufflated CO2, the absorbed CO2, and patient positioning.

Clarifying the mechanism of effect of the Bionator for treatment of maxillary protrusion: A percentile growth study

AIM

The reported effects of Bionator treatment in patients with mandibular retrognathism are conflicting. This study evaluated the changes in craniofacial morphology resulting from treatment with a Bionator, based on measurement percentiles previously reported, to clarify the mechanism of the effect of this commonly used functional device.

MATERIALS AND METHODS

Study Design: Retrospective.

SETTING

A private orthodontic clinic.

PARTICIPANTS

Forty-two children (mean age, 10.13 years) requiring treatment with a Bionator for Class II malocclusion (mandibular retrognathism). Children were randomly assigned to a Bionator group with or without an expansion screw. Measurements on lateral cephalometric radiographs were taken before and upon completion of Bionator treatment. All parameters measured were characterised according to the measurement percentiles previously reported. Each parameter was compared before and after treatment for all patients and for each treatment group using Wilcoxon's test.

RESULTS

No significant differences in cranial length or mandibular body length were seen in any of the 3 groups, but anterior cranial base length and maxillary length were significantly decreased while mandibular ramus height and mandibular length were significantly increased after treatment in the Bionator with expansion screw group and in the all-patient group.

CONCLUSIONS

The findings suggest that treatment with a Bionator with expansion screw during the growth and development stage results in increased mandible length and ramus height and inhibits the growth of the maxilla and anterior cranial base bone.

Residual volume in the cuff of the endotracheal tube when the pilot balloon is torn off instead of deflated using a syringe

BACKGROUND

In recent years, there has been a shift in airway management with the use of cuffed endotracheal tubes (ETT) in pediatric patients. While the use of a syringe to deflate the cuff is generally recommended, anecdotal observations suggest that some healthcare practitioners tear off the pilot balloon from ETT to deflate the cuff. This study was conducted to estimate the residual volume in the cuff when the pilot balloon is torn off for deflation.

METHOD

The in vitro study was conducted in three phases. In phases 1 and 2, various sized cuffed ETTs (3.0, 4.0, and 5.0 mm) were inflated to achieve an intracuff pressure of 20-30 cmH2O in open atmosphere (phase 1) or inside a tube to simulate external pressure from the tracheal wall (phase 2). The pilot balloons were ripped off and the residual volume in the cuff was measured. The process was repeated using 10 ETTs of each of the 3 sizes. In phase 3, the same process was repeated using ten, size 7.0 cuffed ETTs inflated in an intubating mannequin.

RESULTS

In phase 1, the percentage of the remaining residual volume was 60.7, 72.8, and 69.5% in 3.0, 4.0, and 5.0 mm ETTs respectively. Although the percentage of residual volume in phases 2 and 3 was less than phase 1, the residual volume in phases 2 and 3 still averaged approximately 60-70% of the volume required for cuff inflation. In one case, the pilot balloon tube was completely occluded and the residual volume in the cuff could not be expelled even with external pressure.

CONCLUSION

Since significant percentage of the volume remained in the cuff after tearing off the pilot balloon tube with one being completely occluded, we would not recommend this method for cuff deflation.