A modified technique of tubeless anaesthesia for microlaryngoscopy and bronchoscopy in young children with stridor

Comparison of the application of high-flow nasal oxygen with two different oxygen concentrations in infant and child laryngotracheal surgery

Background

This study aimed to compare the use of the STRIVE Hi technique with 70 and 100% oxygen concentrations in children with 1st or 2nd degree laryngeal obstruction undergoing suspension laryngoscopic surgery.

Methods

Children aged 1 month to 6 years scheduled for suspension laryngoscopic surgery with spontaneous respiration were randomly divided into the 70% oxygen concentration group (HFNO70% group) and the 100% oxygen concentration group (HFNO100% group). The data recorded for all the patients included age and sex, comorbidities, preoperative physiological status, methods of induction and maintenance of anesthesia, course of the disease and surgical options, and duration of operation. The primary endpoint was the lowest oxygen saturations during the surgery. The secondary endpoints included the partial pressure of oxygen PaO2, the arterial pressure of carbon dioxide PaCO2, the peak transcutaneous carbon dioxide PtcCO2, and the incidence of desaturation (defined as SpO2 < 90%) or hypercarbia (PtcCO2 > 65 mmHg).

Results

A total of 80 children with 1st or 2nd degree laryngeal obstruction were included in the analysis. The median [IQR (range)] duration of spontaneous ventilation using STRIVE Hi was 52.5 [40–60 (30–170)]min and 62.5 [45–81 (20–200)]min in the HFNO 70% and HFNO 100% groups, respectively (p = 0.99); the lowest oxygen saturation recorded during the operation was 97.8 ± 2.1% and 96.8 ± 2.5%, respectively (p = 0.053); the mean PaO2 at the end of surgery was 184.6 ± 56.3 mmHg and 315.2 ± 101.3 mmHg, respectively (p < 0.001); and the peak transcutaneous CO2 was 58.0 ± 13.0 mmHg and 60.4 ± 10.9 mmHg, respectively (p = 0.373), despite a long operation time.

Conclusion

STRIVE Hi had a positive effect on children undergoing tubeless laryngeal surgery with spontaneous ventilation, and for children with 1st or 2nd degree laryngeal obstruction, there was no significant difference in maintaining the intraoperative oxygenation between the 70 and 100% oxygen concentration groups. The 100% oxygen concentration group showed significant hyperoxia, which has been proven to be associated with multiple organ damage. Using a relatively lower oxygen concentration of 70% can effectively reduce the hazards associated with hyperoxia compared to 100% oxygen concentration.

Clinical trial registration

[www.chictr.org.cn], identifier [CHICTR2200064500].

Early experience with high-flow nasal oxygen therapy (HFNOT) in pediatric endoscopic airway surgery

OBJECTIVE

Reporting our institutional experience with high-flow nasal oxygen therapy (HFNOT), a recently-introduced technique, for endoscopic airway approaches.

METHODS

Prospective collection of data of children (<16 years) undergoing endoscopic between January 2016 and August 2017 at a tertiary referral university hospital.

RESULTS

HFNOT was used in 6 children who underwent 14 procedures for different forms and causes of upper airway obstruction of various origins. No intraoperative complications; related to oxygenation were observed, and the surgical procedures could be carried out as; initially planned.

CONCLUSIONS

We found that HFNOT is an effective and safe technique with a variety of potential applications in the field of endoscopic pediatric airway surgery.

Nasal high-flow oxygen delivery in children with abnormal airways

BACKGROUND

Transnasal Humidified Rapid-Insufflation Ventilatory Exchange has been shown to safely prolong the safe apnea time in well children post induction of anesthesia and is rapidly becoming a new standard for apneic oxygenation in adults. The same oxygenation technique is described as nasal high flow and can be used in infants and children at risk of apnea during anesthesia.

AIM

We investigated the use of nasal high flow oxygen delivery during anesthesia in children with abnormal airways requiring tubeless airway assessment or surgery.

METHODS

Data and outcomes of pediatric patients receiving nasal high flow for upper airway procedures were analyzed. Four categories were defined: (i) tubeless airway surgery, (ii) flexible bronchoscopy, (iii) expected difficult airway, and (iv) comorbidity related risk of apnea. Anesthesia was induced intravenously or with sevoflurane (4-8%) and then converted to total intravenous anesthesia aiming for spontaneous ventilation. Age appropriate nasal high flow cannulae were secured with 100% oxygen delivery at weight-related flow rates. Topicalization of the airway was achieved with lignocaine. Complication rates of desaturation requiring interruption of procedure for rescue oxygenation were recorded.

RESULTS

Twenty children were analyzed with age range of 5 days to 11 years, ASA 1-4, and weight range 3-57 kg. Fifteen were induced with sevoflurane and 100% oxygen, five received total intravenous anesthesia only. All children received Optiflow™ nasal high flow and intravenous anesthesia during their procedure. Average SpO₂ recorded was 96% with lowest SpO₂ 77%. One required rescue oxygenation. Median length of procedure was 32 min, (range 3-61). Most common indication was tubeless airway surgery but seven children had more than one indication.

CONCLUSION

Nasal high flow can be used in spontaneously breathing children with abnormal airways for maintenance of oxygenation during anesthesia for tubeless airway procedures.

State-Dependent Laryngomalacia in Sleeping Children

Laryngomalacia is a common congenital laryngeal abnormality. Despite its being widely discussed in the literature, the pathophysiology is not clearly understood. Both anatomic and neuromuscular theories have been suggested to explain laryngomalacia. We report 4 cases of laryngomalacia in which the presenting signs occurred during sleep. Awake flexible nasopharyngolaryngoscopy failed to demonstrate supraglottic structure collapse. Only while the patients were breathing spontaneously under general anesthesia was laryngomalacia noted. A proposed algorithm for diagnosis and treatment is included. These 4 cases of state-dependent laryngomalacia support a neuromuscular cause for laryngomalacia.

Tubeless anaesthesia with sevoflurane and propofol in adult laryngeal surgery

The presence of endotracheal intubation tube or jet ventilation cannula can compromise free view and access to operation area in certain endolaryngeal operations. The objective of this prospective study was to test whether adequate level of anaesthesia could be obtained in adults using tubeless sevoflurane inhalation anaesthesia with spontaneous breathing. In 23 ASA 1-2 patients, 31 treatments were included in the study of which 19 were laser-assisted papilloma or other tumour resections and 12 were fascia injection laryngoplasties. Anaesthesia was induced with propofol and maintained by insufflating sevoflurane mixture to the patient's oropharynx. The adequacy of the anaesthesia level was assessed by monitoring bispectral index, haemodynamic parameters and peripheral oxygen saturation during the anaesthesia. The ENT surgeon estimated operating conditions, whilst the two participating anaesthesiologists assessed the quality of anaesthesia using a 100 mm VAS scale. Sevoflurane contamination in the operating theatre was measured during five treatments. Mean bispectral index was below 40 throughout the operation. Haemodynamic parameters showed only minor changes during the anaesthesia. Both attending anaesthesiologists and operating ENT surgeon were satisfied with the quality of the anaesthesia and operating conditions (VAS 83 ± 15, mean ± SD, range 42-100, and VAS 93 ± 10, range 55-100, respectively). Sevoflurane room air contamination was high in most measured cases. The modification of tubeless inhalation anaesthesia used in this study produced adequate level of anaesthesia with stable haemodynamics and good operating conditions. Sevoflurane contamination can be reduced with more efficient scavenging systems.

Anesthesia for a neonate with persistent buccopharyngeal membrane and unilateral choanal atresia

We report our anesthetic management of a neonate who presented with complete persistent buccopharyngeal membrane and unilateral choanal atresia, and underwent examination under anesthesia. Maintaining airway patency and spontaneous respiration were our priority. Intravenous propofol was used to maintain adequate anesthetic depth for flexible laryngotracheoscopy and nasotracheal intubation through the only patent passage. We encountered problems of bradycardia and hypotension. Tracheostomy was performed. Definitive management of the persistent buccopharyngeal membrane was carried out on day 14.

Clinical and biochemical effects of propofol EDTA vs sevoflurane in healthy infants and young children

BACKGROUND

Propofol is frequently used for the induction and maintenance of anaesthesia in children aged 3 years and older. The present study compared the clinical and chemical effects of propofol containing disodium edetate (Diprivan) with that of sevoflurane in children younger than 3 years of age.

METHODS

This was an open-label, comparative, parallel-group study. Fifty-six healthy children were randomly assigned to receive either propofol (n=28; mean age 14.7 months) or sevoflurane (n=28; mean age 13.2 months) for ambulatory surgical procedures. Anaesthesia was induced with nitrous oxide (60%), oxygen and sevoflurane (8%). In the propofol group, it was followed by an intravenous infusion of propofol at a rate of 200 microg.kg(-1).min(-1). For the sevoflurane group, anaesthesia was maintained with sevoflurane (1.5-2.5%). Haemodynamic measurements, recovery time and side-effects were recorded. Ionized calcium and magnesium concentrations in blood were measured. Statistical analysis was performed using ancova and the Fisher's exact test.

RESULTS

The effects of propofol were similar to those of sevoflurane with respect to haemodynamic profile, recovery times (20 min vs 19.4 min) and side-effects (i.e. vomiting 10.7% vs 7.1%). Throughout the study, there were no significant differences between the mean ionized calcium and ionized magnesium concentrations in the two groups.

CONCLUSIONS

In children younger than 3 years of age, propofol containing ethylenediaminetetraacetic acid has a similar profile to sevoflurane with respect to haemodynamic effects, recovery times, side-effects, ionized calcium and ionized magnesium levels.

Propofol Decreases Waste Anesthetic Gas Exposure During Pediatric Bronchoscopy

OBJECTIVE

This study compared the anesthetic gas exposure and operating conditions during insufflation anesthesia with halothane-alone versus halothane-propofol in children undergoing direct laryngobronchoscopy.

STUDY DESIGN

Forty-six children were enrolled in this randomized prospective study, with institutional review board approval and informed consent.

METHODS

All children were anesthetized by halothane mask induction and anesthesia was maintained using spontaneous ventilation with insufflation. No muscle relaxants or opioids were used. In the halothane group, halothane was titrated as needed. In the propofol group, halothane was decreased to 1% inspired concentration and the propofol was titrated as needed to maintain spontaneous ventilation and a still patient. Trace anesthetic gases, hemodynamic stability, and operating conditions were measured.

RESULTS

The groups were similar in age, weight, and bronchoscopy time. There was significantly less gas exposure in the propofol group (25 +/- 33 parts per million) versus the halothane group (66 +/- 97 ppm; P <.02). There was a trend toward earlier emergence in the halothane group (33 +/- 13 minutes) versus the propofol group (41 +/- 17 minutes). Postoperative stridor was common, occurring in 30% of children.

CONCLUSIONS

Insufflation anesthesia with spontaneous respiration provides excellent surgical conditions for laryngobronchoscopy. The addition of propofol resulted in fewer airway complications (P =.047). Although the addition of propofol significantly decreased anesthetic gas exposure in the operating room, both techniques resulted in operating room pollution that exceeded the maximum levels of 2 ppm per hour recommended by the US National Institute for Occupational Safety and Health (NIOSH).

Comparison of remifentanil and alfentanil during anaesthesia for patients undergoing direct laryngoscopy without intubation

BACKGROUND

Remifentanil and alfentanil are opioids often used during direct laryngoscopy (DL). This prospective, randomized study compared these agents with respect to haemodynamic and Bispectral Index (BIS) responses, glottic visualization, and rapidity of recovery (spontaneous ventilation, eye opening) in DL without intubation.

METHODS

A total of 60 patients undergoing DL were randomized into two groups: remifentanil (R) and alfentanil (A). Anaesthesia was induced with propofol 2.5 mg kg(-1) and the opioid was administered 1 min later (R=2 microg kg(-1) or A=30 microg kg(-1) over 30 s). DL was commenced 1 min after (corresponding to 3 min after the beginning of induction). Glottic visualization, opioid and/or propofol re-injection, spontaneous ventilation recovery, and eye opening were recorded.

RESULTS

During DL, mean arterial pressure (MAP) increased by 6% in the R group vs 20% in the A group (P<0.05) when compared with post-induction values without affecting heart rate or BIS. No significant difference was observed between groups with respect to glottic exposure, opioid and/or propofol re-injection, and spontaneous ventilation recovery (mean (SEM) 3.8 (0.6) min, R group vs 3.2 (0.7) min, A group, NS) or eye opening (7.1 (1.1) min, R group vs 7.4 (0.9) min, A group, NS). Thirty minutes after postanaesthesia care unit (PACU) admission, MAP returned to its pre-induction value in the R group (104 (3) vs 109 (3) at baseline, NS), whereas in the A group MAP remained significantly lower at this time point (96 (4) vs 106 (3) at baseline, P<0.05).

CONCLUSION

This study showed that only remifentanil prevented MAP increase without adverse effects such as bradycardia during DL, and prevented MAP decrease 30 min after PACU admission.

Childhood obesity: a challenge for the anaesthetist?

The definition of childhood obesity has not been standardized in the past, making studies difficult to compare. In spite of this, the increase in the incidence of childhood obesity is evident and has now reached epidemic proportions. Obese children experience few of the medical complications seen in obese adults. Respiratory physiology appears to be most affected, the degree of which is determined by the level of obesity. Although there is a considerable amount of information on the anaesthetic management of the obese adult, very little has been written concerning the obese child. There is less pathology in the obese child when compared with the adult but some evidence shows a higher likelihood of a critical incident occurring when anaesthetizing such children. This shows that we need to be as worried about anaesthetizing the obese child as we are for the obese adult. This concern should increase with increasing body mass index.

Combination propofol-ketamine anaesthesia in sick neonates

Two critically ill, opioid-tolerant neonates were anaesthetized using pancuronium and a mixture of propofol (PROP) and ketamine (KET). Three mg of KET were added per ml (10 mg) of PROP in a single syringe and infused at a rate of 100-150 microg x kg(-1) x min(-1) of the PROP component (30-45 microg x kg(-1) x min(-1) KET). Total doses of 12-15 and 3.6-4.5 mg x kg(-1) of PROP and KET, respectively, were administered. Both patients remained haemodynamically stable throughout their surgical procedures. PROP-KET is a rational and effective combination for intravenous anaesthesia in critically ill neonates who are likely to be opioid-tolerant when an anaesthesia vaporizer is not readily available.