Regurgitation and aspiration of gastric contents in a child during general anaesthesia using the laryngeal mask airway

We present a case report of a child who underwent general anaesthesia for elective surgery in whom regurgitation and aspiration of gastric contents were associated with the use of the laryngeal mask airway (LMA). Bronchospasm developed but mechanical ventilation was not required. The possible mechanisms causing regurgitation are discussed.     

Temporomandibular joint dysfunction following the use of a supraglottic airway device during general anaesthesia: a prospective observational study

Supraglottic airway devices are commonly used to manage the airway during general anaesthesia. There are sporadic case reports of temporomandibular joint dysfunction and dislocation following supraglottic airway device use. We conducted a prospective observational study of adult patients undergoing elective surgery where a supraglottic airway device was used as the primary airway device. Pre-operatively, all participants were asked to complete a questionnaire involving 12 points adapted from the Temporomandibular Joint Scale and the Liverpool Oral Rehabilitation Questionnaire. Objective measurements included inter-incisor distance as well as forward and lateral jaw movements. The primary outcome was the inter-incisor distance, an accepted measure of temporomandibular joint mobility. Both the questionnaire and measurements were repeated in the postoperative period and we analysed data from 130 participants. Mean (SD) inter-incisor distance in the pre- and postoperative period was 46.5 (7.2) mm and 46.3 (7.5) mm, respectively (p = 0.521) with a difference (95%CI) of 0.2 (−0.5 to 0.9) mm. Mean (SD) forward jaw movement in the pre- and postoperative period was 3.6 (2.4) mm and 3.9 (2.4) mm, respectively (p = 0.018). Mean (SD) lateral jaw movement to the right in the pre- and postoperative period was 8.9 (4.1) mm and 9.1 (4.0) mm, respectively (p = 0.314). Mean (SD) lateral jaw movement to the left in the pre- and postoperative period was 8.8 (4.0) mm and 9.3 (3.6) mm, respectively (p = 0.008). The number of patients who reported jaw clicks or pops before opening their mouth as wide as possible was 28 (21.5%) vs. 12 (9.2%) in the pre- and postoperative period, respectively (p < 0.001) with a difference (95%CI) of 12.3% (6.7–17.9%). There was no significant difference in the responses to the other 11 questions or in the number of patients who reported pain in the temporomandibular joint area postoperatively. No clinically significant dysfunction of the temporomandibular joint following the use of supraglottic airway devices in the postoperative period was identified by either patient questionnaires or objective measurements.     

Critical incidents in paediatric anaesthesia: an audit of 10 000 anaesthetics in Singapore

BACKGROUND: We undertook an audit of paediatric perioperative incidents in the first 10000 anaesthetics administered in KK Women's and Children's Hospital in Singapore between May 1997 and April 1999. The spectrum of surgery performed ranged from simple ambulatory surgery to open heart surgery for complicated congenital heart diseases. METHODS: An audit form is completed for every anaesthetic delivered and critical incidents are reported on the reverse blank page of the audit form. An anaesthetic incident was defined as 'any incident which affected, or could have affected, the safety of the patient under anaesthetic care'. RESULTS: Two hundred and ninety-seven critical incidents were reported. The majority of them happened in healthy patients (80.1% ASA I and II) scheduled for elective surgery (73.3%). Critical incidents in infants less than 1 year of age were four times as common as in older children (8.6% versus 2.1%). Incidents occurred mainly during maintenance (80.6%). There was no anaesthetic mortality. Respiratory events were the most common (77.4%) with laryngospasm accounting for 35.7%. Cardiovascular incidents (10.8%) included hypotension from haemorrhage and sepsis, and dysrhythmias. The incidence of equipment and pharmacologically related problems was low. CONCLUSIONS: Future reviews of a larger patient population may be helpful to determine trends of perioperative events and whether quality assurance programs have made a difference.     

Risk of epilepsy in surgical patients undergoing general or neuraxial anaesthesia

Limited information is available on the risks of epilepsy after surgery in patients receiving general or neuraxial anaesthesia. Using Taiwan's National Health Insurance Research Database, we identified 1,478,977 patients aged ≥ 20 years who underwent surgery (required general or neuraxial anaesthesia with hospitalisation for more than one day) between 2004 and 2011. We selected 235,066 patients with general anaesthesia and 235,066 patients with neuraxial anaesthesia using a frequency‐matching procedure for age and sex. We did not study those with co‐existing epilepsy‐related risk factors. The adjusted rate ratios (RRs) and 95% confidence intervals (CIs) of newly diagnosed epilepsy 1 year after surgery associated with general anaesthesia were analysed in the multivariate Poisson regression model. The one‐year incidence of postoperative epilepsy for patients with general anaesthesia and neuraxial anaesthesia were 0.41 and 0.32 per 1000 persons, respectively, and the corresponding RR was 1.27 (95%CI 1.15–1.41). The association between general anaesthesia and postoperative epilepsy was significant in men (RR = 1.22; 95%CI 1.06–1.40), women (RR = 1.33; 95%CI 1.15–1.55) and 20–39‐year‐old patients. The risk of postoperative epilepsy increased in patients with general anaesthesia who had co‐existing medical conditions and postoperative complications.     

The use of the cuffed oropharyngeal airway in paediatric patients

BACKGROUND: The cuffed oropharyngeal airway (COPA) is a device which has already been demonstrated to be suitable for anaesthetized adult patients undergoing either spontaneous or mechanical ventilation. There are few reports on the use of the COPA in children. In this study, the authors assessed the COPA in paediatric patients undergoing minor surgery. METHODS: The same anaesthesiologist inserted the COPA in 40 consecutive paediatric patients, ASA I and II, aged 1.8-15.3 years. (7.4 +/- 3.9), after induction of anaesthesia with N2O/O2/sevoflurane. COPA size was chosen by measuring the distal tip of the device at the angle of the jaw with the COPA perpendicular to the patient's bed. The proper positioning of the COPA was assessed by observing thoracoabdominal movements, regular capnograph trace, the reservoir bag movements and SpO2 > 94% with a fraction of inspired oxygen of 0.5. Anaesthesia was maintained with 1 MAC halothane, sevoflurane, or isoflurane in N2O/O2 (50%) and the patients were spontaneously breathing. The stability of the COPA following changes in head, neck and body position was tested. We recorded the duration time for COPA insertion, the side-effects of placement of the COPA and during the intraoperative period, the number of attempts, the type of manipulation in order to provide an effective airway and postoperative symptoms, such as the presence of blood on the device, sore throat, neckache, jaw pain and PONV. RESULTS: Successful COPA insertion at the first attempt was 90% and at the second attempt in the remaining 10%. The most frequent airway manipulations were head tilt in 27.5% (obtained by a pillow under shoulders) and chin lift in 5%. No complications both at COPA placement nor during the intraoperative period were observed. On the basis of weight and age, the COPA size was no. 8 in 50%, no. 9 in 30%, no. 10 in 12.5%, and no. 11 in 7.5%. The COPA demonstrated stability after changes in head, neck and body position. Postoperative complications were the presence of blood stains in one case and PONV in six cases (15%). CONCLUSIONS: The COPA is an extratracheal airway device suitable in paediatric patients undergoing general anaesthesia with spontaneous ventilation for minor surgery and other painful procedures. This study shows that for paediatric patients: (i) complications seem to be rare; (ii) the COPA allows hands free anaesthesia; (iii) specific indication for the COPA could be obese patients with a small mouth; and (iv) COPA sizing can be easily established by the weight or age of the patients.     

Continuous monitoring of oesophageal pH during general anaesthesia with laryngeal mask airway in children

We studied the incidence of gastro-oesophageal reflux (GOR) during general anaesthesia with the laryngeal mask airway (LMA) in a paediatric population with two ventilatory regimes: spontaneous breathing and controlled mechanical ventilation (CMV). Thirty children between 6 months and 15 years, ASA I-II, for routine surgery, were randomly assigned in two groups: spontaneous ventilation (n=14), and CMV (n=16). A pH probe was situated in the central third of the oesophagus. Some 66% of the patients breathing spontaneously had GOR episodes vs. 92% of the patients with CMV (P < 0,01). Reflux took place mainly after LMA removal (21% vs. 68%; P < 0,01) and in the Postanaesthetic Care Unit (PACU) (29% vs. 43%; P < 0,05). There was a high incidence of GOR during general anaesthesia and in the PACU in paediatric patients anaesthetized with the LMA. GOR episodes were significantly more evident in the CMV group, mainly after LMA removal, but without clinical significance.     

Preoperative assessment and preparation for safe paediatric anaesthesia

The delivery of anaesthesia to children and young people provides unique challenges. A careful, systematic approach to assessment and preparation can deliver a positive experience for the child, carers and staff while mitigating potential complications. Preparation for anaesthesia should encompass information gathering, assessment and planning for anatomical, physiological, social and behavioural elements specific to the child and the surgery. Delivery of appropriate information, consent and fasting are also key elements of ensuring positive perioperative outcomes. We consider the common components of preparation for the delivery of safe paediatric anaesthesia.     

Preoperative assessment and preparation for safe paediatric anaesthesia

The delivery of anaesthesia to children and young people provides unique challenges. A careful, systematic approach to assessment and preparation can deliver a positive experience for the child, carers and staff while mitigating potential complications. Preparation for anaesthesia should encompass information gathering, assessment and planning for anatomical, physiological, social and behavioural elements specific to the child and the surgery. Delivery of appropriate information, consent and fasting are also key elements of ensuring positive perioperative outcomes. We consider the common components of preparation for the delivery of safe paediatric anaesthesia.     

The upper airway during anaesthesia

Upper airway obstruction is common during both anaesthesia andsleep. Obstruction is caused by loss of muscle tone presentin the awake state. The velopharynx, a particularly narrow segment,is especially predisposed to obstruction in both states. Patientswith a tendency to upper airway obstruction during sleep arevulnerable during anaesthesia and sedation. Loss of wakefulnessis compounded by depression of airway muscle activity by theagents, and depression of the ability to arouse, so they cannotrespond adequately to asphyxia. Identifying the patient at riskis vital. Previous anaesthetic history and investigations ofthe upper airway are helpful, and a history of upper airwaycompromise during sleep (snoring, obstructive apnoeas) shouldbe sought. Beyond these, risk identification is essentiallya search for factors that narrow the airway. These include obesity,maxillary hypoplasia, mandibular retrusion, bulbar muscle weaknessand specific obstructive lesions such as nasal obstruction oradenotonsillar hypertrophy. Such abnormalities not only increasevulnerability to upper airway obstruction during sleep or anaesthesia,but also make intubation difficult. While problems with airwaymaintenance may be obviated during anaesthesia by the use ofaids such as the laryngeal mask airway (LMA), identificationof risk and caution are keys to management, and the airway shouldbe secured before anaesthesia where doubt exists. If trachealintubation is needed, spontaneous breathing until intubationis an important principle. Every anaesthetist should have inmind a plan for failed intubation or, worse, failed ventilation. Br J Anaesth 2003; 91: 31–9     

An evaluation of the laryngeal mask airway during routine paediatric anaesthesia

During a six week period, all anaesthetists at the Royal Hospital for Sick Children, Glasgow were asked to complete a questionnaire whenever a laryngeal mask airway (LMA) was used. Seniority of anaesthetist, age of patient, anaesthetic technique, technique of LMA insertion, ease of LMA insertion, and any problems encountered either during LMA insertion, or during induction, maintenance, and recovery from anaesthesia were documented. Complete data were obtained from 211 patients aged 5 weeks to 15 years. Ninety-six children were anaesthetized by consultant paediatric anaesthetists, and 115 by trainees. LMA insertion was successful at the first attempt in 86% of all cases, achieved with some difficulty in 11% of cases, and failed or its use was abandoned in 6 cases (3%). Difficulties other than with LMA placement per se occurred in 11% of cases during induction of anaesthesia. Seniority of anaesthetist and choice of anaesthetic agent influenced neither the success rate of insertion nor the frequency of other difficulties encountered during induction of anaesthesia. Significantly fewer problems were encountered at LMA removal if this was done during deep anaesthesia compared with removal when protective reflexes were present (P < 0.05).     

Respiratory complications during anaesthesia in Apert syndrome

BACKGROUND: Clinical experience with anaesthesia for a series of patients with Apert syndrome (craniosynostosis, midface hypoplasia and syndactyly) has not been reported previously. METHODS: In this review, 10 years of experience was examined at our hospital. There were 145 anaesthetics administered to 18 individuals. RESULTS: There were 16 complications (15 were perioperative wheezing) which occurred in seven patients. In four cases, surgery was cancelled due to intractable wheezing. CONCLUSIONS: We could not demonstrate any benefit from preoperative administration of nebulized albuterol. Paediatric anaesthetists should be aware of this high incidence of respiratory complications in Apert syndrome.     

Major complications of airway management: a prospective multicentre observational study

We conducted an observational study of serious airway complications, using similar methods to the fourth UK National Audit Project (NAP4) over a period of 1 year across four hospitals in one region in the UK. We also conducted an activity survey over a week, using NAP4 methods to yield an estimate for relevant denominators to help interpret the primary data. There were 17 serious airway complications, defined as: failed airway management leading to cancellation of surgery (eight); airway management in recovery (five); unplanned intensive care admission (three); and unplanned emergency front of neck access (one). There were no reports of death or brain damage. This was an estimate of 0.028% (1 in 3600) complications using the denominator of 61,000 general anaesthetics per year in the region. Complications in patients with ‘predicted easy’ airways were rare (approximately 1 in 14,200), but 45 times more common in those with ‘predicted difficult’ airways (approximately 1 in 315). Airway management in both groups was similar (induction of anaesthesia followed by supraglottic airway or tracheal tube). Use of awake/sedation intubation, videolaryngoscopy and high-flow nasal oxygenation were uncommon even in the predicted difficult airway patients (in 2.7%, 32.4% and 9.5% of patients, respectively). We conclude that the incidence of serious airway complications is at least as high as it was during NAP4. Despite airway prediction being used, this is not informing subsequent management.     

Postobstructive pulmonary oedema during anaesthesia in children with mucopolysaccharidoses

We present case reports of five patients with severe forms of mucopolysaccharidoses who developed postobstructive pulmonary oedema during anaesthesia. The difficulties of anaesthesia in these patients and the particular predisposition that these patients exhibit for the development of postobstructive pulmonary oedema is discussed.     

Anticipated difficult airway during obstetric general anaesthesia: narrative literature review and management recommendations.

We reviewed the literature on management of general and regional anaesthesia in pregnant women with anticipated airway difficulty. We identified 138 publications comprising 158 cases; these either described equipment or techniques for the provision of general anaesthesia, or the management of women with regional analgesia or anaesthesia, with the aim of avoiding general anaesthesia. Most of the former group described women requiring caesarean section alone, or in combination with other surgery, which was sometimes airway-related. Management techniques were largely similar to those in non-obstetric patients requiring surgery who have airway difficulties, although suggested differences related to physiological changes of pregnancy and avoidance of nasal intubation. In the reports discussing regional anaesthesia, consideration was often given to the possible requirement for urgent out-of-hours anaesthetic intervention, and the predicted difficulty of management of general anaesthesia should it be required. In a number of reported cases, multidisciplinary planning led to the conclusion that elective caesarean section should be performed in order to avoid emergency airway management. Based on this literature review, we advise antenatal planning that includes: assessment of the patient's clinical characteristics; consideration of the equipment and personnel available to provide safe airway management out-of-hours; and elective caesarean section should these be lacking. If general anaesthesia is required, a risk assessment must be made as to the probability of safe airway management after the induction of anaesthesia, and awake tracheal intubation should be used if this cannot be assured. Decision aids are provided to illustrate these points. Online appendices include a comprehensive compendium of case reports on the management of a number of rare syndromes and airway conditions.     

The laryngeal mask airway in paediatric anaesthesia

Forty-eight children, aged between 2 and 10 years, admitted as day cases for otological surgery were allocated at random into two groups. The first group was anaesthetised using a standard facemask, and the second with a laryngeal mask airway. The laryngeal airway produced a satisfactory airway in all children, and was inserted on the first attempt in 67% of patients. Hypoxia was significantly less frequent in the laryngeal airway group (p less than 0.05), and there were significantly fewer interruptions to surgery than in the facemask group (p less than 0.001). Patient safety, operating and anaesthetic conditions were all considered superior in the laryngeal airway group.     

Accidental awareness during general anaesthesia – a narrative review

Unintended accidental awareness during general anaesthesia represents failure of successful anaesthesia, and so has been the subject of numerous studies during the past decades. As return to consciousness is both difficult to describe and identify, the reported incidence rates vary widely. Similarly, a wide range of techniques have been employed to identify cases of accidental awareness. Studies which have used the isolated forearm technique to identify responsiveness to command during intended anaesthesia have shown remarkably high incidences of awareness. For example, the ConsCIOUS‐1 study showed an incidence of responsiveness around the time of laryngoscopy of 1:25. On the other hand, the 5th Royal College of Anaesthetists National Audit Project, which reported the largest ever cohort of patients who had experienced accidental awareness, used a system to identify patients who spontaneously self‐reported accidental awareness. In this latter study, the incidence of accidental awareness was 1:19,600. In the recently published SNAP‐1 observational study, in which structured postoperative interviews were performed, the incidence was 1:800. In almost all reported cases of intra‐operative responsiveness, there was no subsequent explicit recall of intra‐operative events. To date, there is no evidence that this occurrence has any psychological consequences. Among patients who experience accidental awareness and can later remember details of their experience, the consequences are better known. In particular, when awareness occurs in a patient who has been given neuromuscular blocking agents, it may result in serious sequelae such as symptoms of post‐traumatic stress disorder and a permanent aversion to surgery and anaesthesia, and is feared by patients and anaesthetists. In this article, the published literature on the incidence, consequences and management of accidental awareness under general anaesthesia with subsequent recall will be reviewed.     

Prevention and management of complications of airway surgery in children

Preventing and managing complications of airway surgery in children requires proactive attention to both surgical and anaesthetic aspects of the planned procedure. Preoperative evaluation should include a thorough physical examination and, especially in children with multiple congenital anomalies, flexible fibreoptic nasopharyngolaryngoscopy, direct laryngoscopy and rigid or flexible bronchoscopy. The goal is to identify dynamic abnormalities such as laryngomalacia or vocal cord paralysis, tracheal or bronchial lesions, gastro-oesophageal reflux disease (GORD), aspiration, laryngotracheal stenosis, totally obstructing tracheostomy-associated granulation tissue and Noonan syndrome preoperatively, and then to plan surgical management to achieve the best possible outcome for each patient.     

A prospective,cohort evaluation of major and minor airway management complications during routine anaesthetic care at an academic medical centre

The aim of this study was to develop an audit tool to identify prospectively all peri‐operative adverse events during airway management in a cost‐effective and reproducible way. All patients at VU University Medical Center who required general anaesthesia for elective and emergency surgical procedures were included during a period of 8 weeks. Daily questionnaires and interviews were taken from anaesthesia trainees and anaesthetic department staff members. A total of 2803 patients underwent general anaesthesia, 1384 men and 1419 women, including 2232 elective patients and 571 emergency procedures, 697 paediatric and 2106 adult surgical procedures. A total of 168 airway‐related events were reported. The incidence of severe airway management‐related events was 24/2803 (0.86%). There were 12 (0.42%) unanticipated ICU admissions, two patients (0.07%) required a surgical airway. There was one (0.04%) death, one cannot intubate cannot oxygenate (0.04%), one aspiration (0.04%) and eight (0.29%) severe desaturations < S_pO₂ 50%. We suggest that our method to determine and investigate airway management‐related adverse events could be adopted by other hospitals.     

The size 1.5 laryngeal mask airway (LMA) in paediatric anaesthetic practice

BACKGROUND: The recently introduced size 1.5 laryngeal mask airway (LMA) is specifically designed for use in children weighing 5-10 kg. METHODS: We prospectively evaluated its use in 68 patients, mean age 8.7 months, who were undergoing a variety of routine surgical procedures. RESULTS: The overall incidence of complications was high (42%) and was significantly more common in younger patients. Most of these related to poor positioning of the LMA, or airway problems such as obstruction or laryngospasm. Critical incidents occurred in seven patients, and all but one of these was related to the use of an LMA. CONCLUSIONS: The size 1.5 LMA is a useful addition to the range available, although the overall complication rate is considerable and is inversely related to the age of the child.     

Midazolam sedation and local anaesthesia compared with general anaesthesia for paediatric outpatient dental surgery

Midazolam sedation may offer an alternative to general anaesthesia for dental treatment in children. This study evaluated the efficacy and safety of i.v. midazolam with local anaesthesia in uncooperative paediatric dental patients. Thirty children (aged 2–10 years, physical status ASA 1 or 2) were randomized into two groups to receive general anaesthesia (group G) or local anaesthesia during sedation with i.v. midazolam (group M). Incremental doses of midazolam 0.05 mgkg^-1 were given to a sedative endpoint of 2 on a Sedation Scale of 5–0 (hyperactive–asleep), or 0.4 mgkg^-1 maximum, then as needed to maintain the same level of sedation. Amnesia was tested at the sedative endpoint by showing the child a tinkling ball and checking recall 1 h after surgery. Recovery was assessed by the Post-Anesthetic Recovery Scale at 3 h (0–10) with 10 representing readiness for discharge. Questionnaires were completed by the dentist and anaesthetist during recovery and by telephone to the parents 1–2 weeks later. Dental treatment was completed according to protocol in 11 of the 15 patients in group M (sedative doses: 0.27 0.09 mgkg^-1, mean SD) and all patients in group G. Recovery was similar in both groups, with discharge criteria met after 1 h 30 min in all but one group M patient. None had recall for intra-operative events. However, the variability of responsiveness makes midazolam unreliable when used alone to facilitate dental treatment, and the high dose requirements make close monitoring of paediatric patients mandatory.