Anaesthesia related mortality data at a Tertiary Pediatric Hospital in Western Australia.

BACKGROUND: Anaesthesia related mortality in paediatrics is rare. There are limited data describing paediatric anaesthesia related mortality. This study determined the anaesthesia related mortality at a Tertiary Paediatric Hospital in Western Australia. METHODS: A retrospective cohort study of children under-18 years of age, that died within 30-days of undergoing anaesthesia at Princess Margaret Hospital (PMH), between 01 January 2001 and 31 March 2015. A senior panel of clinicians reviewed each death to determine whether the death was (i) due wholly to the provision of anaesthesia (ii) due partly to the provision of anaesthesia or (iii) if death was related to the underlying pathology of the patient and anaesthesia was not contributory. Anaesthesia related mortality, 24-h and 30-day mortality as well as predictors of mortality were determined. RESULTS: A total of 154,538 anaesthetic events were recorded. There were 198 deaths within 30-days of anaesthesia. Anaesthesia attributable mortality was 0.19/10,000 with all anaesthesia deaths occuring in patients undergoing cardiothoracic surgery. The 24-h and 30-day all-cause mortality rate was 3.43/10,000 (95% CI 2.57-4.49) and 9.38/10,000 (95% CI 7.92-11.04), respectively. Overall mortality was 12.34/10,000 (95% CI 11.09-14.73) Age less than 1-year, cardiac surgery, emergency surgery and higher ASA score were all significant predictors of mortality. CONCLUSION: Paediatric anaesthesia related mortality as reflected in this retrospective cohort study is uncommon. Significant risk factors were determined as predictors of mortality.

The impact of surgical cancellations on children, families, and the health system in an Australian paediatric tertiary referral hospital.

BACKGROUND: Reasons for elective surgery cancelations and their impact vary from one institution to another. Cancelations have emotional and financial implications for patients and their families. Our service has a particularly broad and geographically diverse patient population; hence, we sought to examine these impacts in our service. METHODS: We identified families with procedural cancelations and administered a telephone questionnaire. Survey items included the reason for and timing of cancelation, how the family was informed, the mode of transport and distance traveled to the hospital, associated leave from work, expenses, whether the child was required to fast, missed school, as well as the child's and parent's emotional responses to the cancelation, along with overall parental satisfaction with how the cancelation was handled. RESULTS: During our study period, a total of 7870 procedures were booked. 6734 (86%) of these were completed and 1136 (14%) were canceled, with 6% canceled on the day of surgery. In 750 (66%) of these cancelations, families were successfully contacted by telephone and agreed to participate. Of these 305 (41%) cancelations were family-initiated and 444 (59%) were hospital-initiated, with these hospital-initiated cancelations occurring closer to scheduled surgery. The most common cause of cancelation was that the child could not undergo the procedure due to illness (22%) or being unable attend the hospital (14%). The greatest disruption to families and children occurred when procedures were canceled late, particularly when the cancelation occurred on the day of the planned procedure.

Audit of anesthetic trainees' 'hands-on' operating room experience in an Australian tertiary children's hospital.

BACKGROUND: There are no internationally accepted guidelines about what constitutes adequate clinical exposure during pediatric anesthetic training. In Australia, no data have been published on the level of experience obtained by anesthetic trainees in pediatric anesthesia. There is, however, a new ANZCA (Australian and New Zealand College of Anaesthetists) curriculum that quantifies new training requirements. AIM: To quantify our trainees' exposure to clinical work in order to assess compliance with new curriculum and to provide other institutions with a benchmark for pediatric anesthetic training. METHODS: We performed a prospective audit to estimate and quantify our anesthetic registrars' exposure to pediatric anesthesia during their 6-month rotation at our institution, a tertiary pediatric hospital in Perth, Western Australia. RESULTS: Our data suggest that trainees at our institution will achieve the new ANZCA training standards comfortably, in terms of the required volume and breadth of exposure. Experience, however, of some advanced pediatric anesthetic procedures appears limited. CONCLUSIONS: Experience gained at our hospital easily meets the new College requirements. Experience of fiber-optic intubation and regional blocks would appear insufficient to develop sufficient skills or confidence. The study provides other institutions with information to benchmark against their own trainee experience.

Direct laryngoscopy after potential difficult intubation in children only predicts standard Cormack and Lehane view to within one grade.

BACKGROUND: Some techniques used to achieve intubation in children predicted to have a difficult airway do not involve direct laryngoscopy or assessment of the laryngeal grade. Direct laryngoscopy may therefore be performed immediately after intubation to provide a record for future anesthetics. It is unknown whether this postintubation grade accurately reflects the standard laryngeal grade in this group. AIM: The aim of the study was to identify those children who were predicted to be a difficult intubation and to perform direct laryngoscopy before and after intubation. We set out to ascertain if direct laryngoscopy performed after intubation could accurately predict the standard un-intubated laryngeal grade in this group. METHODS: All children presenting for general anesthesia who were clinically predicted to be a difficult intubation were considered for this study and prospectively recruited. After induction of anesthesia, one study anesthetist performed direct laryngoscopy before and another study anesthetist then performed direct laryngoscopy after intubation. These laryngeal grades were then compared. RESULTS: A total of 21 children were successfully recruited and studied, and all patients were successfully intubated. Overall, the postintubation grade did not reliably reflect the standard grade, but did not differ by more than one grade in any patient. In one-third of subjects, the postintubation grade was equal to the standard grade, in one-third it was a grade 'easier' and in one-third a grade 'harder'. CONCLUSION: Assessment and documentation of a postintubation laryngeal grade does not appear to provide reliable information for future anesthetics and may even have the potential to be misleading. Any such documentation should always refer to the presence of an endotracheal tube and be interpreted with caution.

Ingestion of stimulant medications does not alter bispectral index or clinical depth of anesthesia at 1 MAC sevoflurane in children.

BACKGROUND/AIM: Children treated with stimulant medications for the behavioral management of attention deficit hyperactivity disorder (ADHD) may present for elective surgery. Stimulant medication is often continued until the morning of surgery to optimize perioperative behavior. It is unknown whether such stimulant drug ingestion can affect cerebral arousal and alter depth of anesthesia. A clinically relevant alteration in measured depth of anesthesia could form the basis for an evidence-based recommendation that children taking stimulant medications require a change in the amount of anesthetic delivered or that they require routine monitoring of depth of anesthesia. MATERIALS AND METHODS: Thirty-four ASA 1 and 2 children aged between 5 and 16, presenting for elective day case surgery, were recruited. Seventeen had a diagnosis of ADHD and had taken stimulant medication on the day of surgery, and 17 were controls. A standard inhalational induction of anesthesia using air, oxygen, and sevoflurane by facemask was performed and maintained for 10 min at 1 MAC endtidal sevoflurane. During this time, no other stimulus was applied to the patient. Bispectral index (BIS) and other markers of depth of anesthesia were recorded after 10 min. RESULTS: Children in both groups were of similar ages and weights. There were a higher percentage of boys in the stimulants group. Baseline physiological parameters were similar in both groups. After induction and equilibration for 10 min of anesthesia at 1 MAC endtidal sevoflurane, there was no significant difference in BIS or clinical markers of depth of anesthesia. CONCLUSIONS: Children taking stimulant medication for ADHD, and who ingest medication on the day of surgery, do not appear to have altered BIS or depth of anesthesia at 1 MAC of sevoflurane. These results do not support a recommendation for a change in anesthetic practice for children having ingested stimulants up to the day of surgery, either in terms of increasing the amount of anesthetic given or monitoring of depth.

Risk assessment for respiratory complications in paediatric anaesthesia: a prospective cohort study.

BACKGROUND: Perioperative respiratory adverse events in children are one of the major causes of morbidity and mortality during paediatric anaesthesia. We aimed to identify associations between family history, anaesthesia management, and occurrence of perioperative respiratory adverse events. METHODS: We prospectively included all children who had general anaesthesia for surgical or medical interventions, elective or urgent procedures at Princess Margaret Hospital for Children, Perth, Australia, from Feb 1, 2007, to Jan 31, 2008. On the day of surgery, anaesthetists in charge of paediatric patients completed an adapted version of the International Study Group for Asthma and Allergies in Childhood questionnaire. We collected data on family medical history of asthma, atopy, allergy, upper respiratory tract infection, and passive smoking. Anaesthesia management and all perioperative respiratory adverse events were recorded. FINDINGS: 9297 questionnaires were available for analysis. A positive respiratory history (nocturnal dry cough, wheezing during exercise, wheezing more than three times in the past 12 months, or a history of present or past eczema) was associated with an increased risk for bronchospasm (relative risk [RR] 8.46, 95% CI 6.18-11.59; p<0.0001), laryngospasm (4.13, 3.37-5.08; p<0.0001), and perioperative cough, desaturation, or airway obstruction (3.05, 2.76-3.37; p<0.0001). Upper respiratory tract infection was associated with an increased risk for perioperative respiratory adverse events only when symptoms were present (RR 2.05, 95% CI 1.82-2.31; p<0.0001) or less than 2 weeks before the procedure (2.34, 2.07-2.66; p<0.0001), whereas symptoms of upper respiratory tract infection 2-4 weeks before the procedure significantly lowered the incidence of perioperative respiratory adverse events (0.66, 0.53-0.81; p<0.0001). A history of at least two family members having asthma, atopy, or smoking increased the risk for perioperative respiratory adverse events (all p<0.0001). Risk was lower with intravenous induction compared with inhalational induction (all p<0.0001), inhalational compared with intravenous maintenance of anaesthesia (all p<0.0001), airway management by a specialist paediatric anaesthetist compared with a registrar (all p<0.0001), and use of face mask compared with tracheal intubation (all p<0.0001). INTERPRETATION: Children at high risk for perioperative respiratory adverse events could be systematically identified at the preanaesthetic assessment and thus can benefit from a specifically targeted anaesthesia management. FUNDING: Department of Anaesthesia, Princess Margaret Hospital for Children, Swiss Foundation for Grants in Biology and Medicine, and the Voluntary Academic Society Basel.

Incidence of sore throat in children following use of flexible laryngeal mask airways - impact of an introducer device.

BACKGROUND: Insertion of a flexible laryngeal mask airway (FLMA) is more difficult and therefore might result in a higher risk for trauma to the upper airway. To facilitate the insertion of FLMA, the use of an introducer device (Portex Limited, Hythe, Kent, UK) was promoted. However, the impact of the use of this device on the occurrence of postoperative sore throat is unknown. METHODS: Four hundred children (3-21 years) undergoing elective ambulatory surgery were consecutively included in this study. In 196 cases, the FLMA was inserted using an introducer device. The FLMA cuff was then inflated and the pressure adjusted to below 60 cmH(2)O (according to manufacturers guidelines) using a calibrated cuff manometer (Portex Limited). Three types of FLMA were available: FLMA classic, FLMA unique (both FLMA PacMed, Richmond, Victoria, Australia) and FLMA ProBreathe (Well Lead Medical Co Ltd., Hualong, Guangzhou, China). Prior to discharge, patients' pain was assessed using an age appropriate scale. RESULTS: Thirteen children (3.3%) developed sore throat, two (0.5%) sore neck and three (0.75%) sore jaw. Of those that developed sore throat, seven had a FLMA inserted with an introducer, six without an introducer. Using a laryngeal mask airways (LMA) with a polyvinyl chloride (PVC), surface was associated with a higher risk for sore throat compared with an LMA with a silicone surface (P = 0.0002). CONCLUSION: In this study with controlled low cuff pressures, the incidence of sore throat was low. The use of an introducer device did not affect the rate of sore throat.

Reduced air leakage by adjusting the cuff pressure in pediatric laryngeal mask airways during spontaneous ventilation.

BACKGROUND: Optimal inflation of the laryngeal mask airway (LMA) cuff should allow ventilation with low leakage volumes and minimal airway morbidity. Manufacturer's recommendations vary, and clinical end-points have been shown to be associated with cuff hyperinflation and increased leak around the LMA. However, measurement of the intra-cuff pressure of the LMA is not routine in most pediatric institutions, and the optimal intra-cuff pressure in the LMA has not been determined in clinical studies. METHODS: This was a prospective audit in 100 pediatric patients undergoing elective general anesthesia breathing spontaneously via LMA (size 1.5-3). Cuff pressure within the LMA was adjusted using a calibrated pressure gauge to three different values (60, 40, and 20 cmH2O) within the manufacturers' recommended LMA cuff pressure range (< or = 60 cmH2O). Three corresponding inspiratory and expiratory tidal volumes were recorded, and the differences were calculated as the 'leak volume'. RESULTS: Compared with 20 and 60 cmH2O intra-cuff pressure, measured leakage volumes were the lowest at cuff inflation pressures of 40 cmH2O [median (range) 0.42 (0.09-1.00) ml x kg(-1)] in most patients (83%), while 17% of children demonstrated minimally smaller leakages at 20 cmH2O [0.51 (0.11-1.79) ml x kg(-1)]. Maximum leakage values occurred with cuff pressures of 60 cmH2O in all groups [0.65 (0.18-1.27) ml x kg(-1)] and were not associated with the smallest value of air leakage in any patient. CONCLUSION: Using cuff manometry, an intra-cuff pressure of 40 cmH2O was associated with reduced leak around the LMA while higher (60 cmH2O) and lower (20 cmH2O) cuff pressures resulted in higher leak volumes during spontaneous ventilation. In spontaneously breathing children, reducing the intra-cuff pressure of pediatric-sized LMAs even below the manufacturers' recommendations allows ventilation with minimized leakage around the LMA cuff.

Laryngeal mask airways--to inflate or to deflate after insertion?

BACKGROUND: Hyperinflation of the laryngeal mask airway (LMA) cuff is known to be a risk factor for airway morbidity and increased leakage around the LMA. While the manufacturers' recommendation is to inflate the cuff with the maximum recommended volumes and/or to adjust the cuff pressure to <60 cmH2O, cuff pressures below 40 cmH2O have been shown to be associated with a minimal rate of sore throat and minimal leakage. However, it remains to be determined whether inflation or deflation is needed to achieve favorable pressures. Therefore, we assessed the need for cuff-volume adjustment following insertion of the LMA unchanged straight from the sterile packaging in a prospective audit. METHODS: One thousand children (0-16 years) undergoing elective surgery were consecutively included in this quality of care audit. After taking the LMA from its sterile packaging, the LMA cuff was emptied and the amount of air recorded. Then, the same amount of air was returned into the LMA, the LMA was inserted into the patient, and the cuff pressure was measured using a calibrated cuff manometer. RESULTS: Following insertion of the LMA (without further inflation or deflation of the cuff), 20.5% of children had cuff pressures > or = 60 cmH2, while 55.7% had LMA cuff pressures <40 cmH2O. Cuff pressures were also significantly higher in size 1 LMAs (66.6% had cuff pressures > or = 60 cmH2O and 2% <40 cmH2O) compared with all other sizes (P < 0.05). Furthermore, cuff pressures in LMAs with a poly vinyl chloride (PVC) surface were higher compared to LMAs with a silicone surface (65.2% > or = 60 cmH2O and 9.3% <40 cmH2O vs 9% > or = 60 cmH2O and 67.6% <40 cmH2O, respectively). CONCLUSIONS: This study demonstrates that LMAs, particularly when using small-sized LMAs or LMAs with a more rigid PVC surface, need to be deflated following insertion of the device rather than inflated to avoid cuff hyperinflation. Hence, cuff pressures should be measured routinely using a manometer to minimize potential pressure-related airway complications.

Impact of laryngeal mask airway cuff pressures on the incidence of sore throat in children.

BACKGROUND: Hyperinflation of laryngeal mask airway cuffs can cause harm to the upper airway mainly by exerting high pressures on pharyngeal and laryngeal structures thus impairing mucosal perfusion. Although cuff manometers can be used to guide the monitoring of cuff pressures, their use is not routine in many institutions. In a prospective audit, we assessed the incidence of sore throat following day-case-surgery in relation to the intracuff pressure within the laryngeal mask airway. METHODS: Four hundred children (3-21 years) were consecutively included in this study. The laryngeal mask airway was inflated as deemed necessary by the attending anesthetist. Cuff pressures were measured using a calibrated cuff manometer (Portex Limited, Hythe, Kent, UK, 0-120 cm H2O, pressures exceeding the measurement range were set at 140 cm H2O for statistical purposes) at induction of anesthesia. RESULTS: Forty-five children (11.25%) developed sore throat, 32 (8%) sore neck and 17 (4.25%) sore jaw. Of those that developed sore throat, 56.5% had cuff pressures exceeding >100 cm H2O. In contrast, when cuff pressures were <40 cm H2O, there were no episodes of sore throat, whilst there was only a 4.6% occurrence of sore throat if cuff pressures were between 40-60 cm H2O. CONCLUSION: We have demonstrated that intra cuff pressure in laryngeal mask airways is closely related to the development of sore throat with higher pressures increasing its likelihood. Hence, cuff pressures should be measured routinely using a manometer to minimize the incidence of sore throat.

Lower cuff pressures improve the seal of pediatric laryngeal mask airways.

BACKGROUND: Hyperinflation of laryngeal mask airway (LMA) cuffs may be harmful because of the exertion of high pressures on pharyngeal and laryngeal structures. Although cuff manometers may be used to monitor cuff pressure, their use is not routine in many institutions and clinical endpoints are used instead. Furthermore, it is common clinical practice to add air to the cuff in the presence of an air leak to obtain a better seal. METHODS: In a prospective audit, the authors assessed air leakage around pediatric sized LMAs (n = 200) following inflation guided by common clinical endpoints (slight outward movement of the LMA) and then following adjustment of the cuff pressure to the recommended pressure range (<60 cmH(2)O) according to institutional guidelines with the use of a calibrated cuff manometer, directly after induction of anesthesia. Following induction, all children were gently ventilated with pressure control ventilation with 10 cmH(2)O and a positive end-expiratory pressure of 5 cmH(2)O. RESULTS: Following inflation of the cuff guided by clinical endpoints, the median initial cuff pressure (LMA size 1-3) was 92 (size 3) to >120 cmH(2)O (size 1) and the median leakage around the cuff ranged from 0.66 to 1.07 ml x kg(-1). Following cuff pressure adjustment according to the recommended pressure range (<60 cmH(2)O), the leakage decreased significantly to 0.51-0.79 ml x kg(-1) (P = 0.002 for size 1, P < 0.001 for size 1.5-3). CONCLUSION: The use of clinical endpoints to inflate LMA cuffs is not only associated with significant hyperinflation in the majority of patients but also with an increased leakage around the LMA cuff when compared with adjusted LMA cuff pressures. Therefore, cuff manometers should routinely be used not only to avoid unnecessary hyperinflation but also to improve cuff sealing of LMA in children.

Can Bispectral Index aid laryngeal mask placement in children?

BACKGROUND: Laryngeal mask airway (LMA) placement requires an adequate depth of anesthesia to prevent patient movement and adverse airway responses. Patient movement, coughing, stridor or laryngospasm at LMA placement may result in transient hypoxia, injury to the patient and prolong time spent in the anesthetic room. The Bispectral Index Score (BIS) is a relatively new tool that has not yet established its place in routine clinical pediatric anesthesia practice. One potential use may be to predict an adequate depth of anesthesia for successful intraoperative interventions such as LMA placement in children. METHODS: A total of 116 children aged between 1 and 16 years due to have an LMA placed under general anesthesia were enrolled into this prospective, blinded observational study. Complication or success of LMA placement was then analyzed in relation to the BIS value at the time of placement. Other clinical variables were also considered. RESULTS: The difference in BIS values in children with complicated compared with successful LMA placement was small and BIS therefore appears not to be a reliable predictor for either. Inexperience of the anesthetist and a history of recent upper respiratory tract infection (URTI) may be better indicators for complications. CONCLUSIONS: Bispectral Index Score appears, from this study, not to be a useful tool to help predict complications of LMA placement or to help reduce airway complications during LMA placement. Other markers may be more useful predictors of adverse airway events.

Anesthesia in a child with newly diagnosed Hypertrophic Cardiomyopathy.

We report the initial resuscitation and subsequent management of a child with newly diagnosed Hypertrophic Cardiomyopathy (HCM), which presented as an out of hospital cardiac arrest. HCM is an autosomal dominant condition that is uncommonly encountered in the pediatric setting and is an important cause of sudden death. Here, we describe the safe use of an anesthetic technique for insertion of an implantable cardioverter-defibrillator that ensured strict hemodynamic stability and modest bradycardia.

Airway management of three cases of congenital cervical teratoma.

Cervical teratomas are rare congenital tumors derived from all three germ cell layers. The vast majority are histologically benign, but the significant size they may attain can potentiate life-threatening upper airway obstruction. All cases require the specialist airway skills of the pediatric anesthetist. This may be planned, in the case of antenatally diagnosed lesions, when the pediatric anesthetist is part of a multidisciplinary team involved in an EX utero Intrapartum Treatment (EXIT) or Operation On Placental Support (OOPS) procedure, or when a neonate is undergoing elective excision in the early neonatal period as definitive treatment. Alternatively the anesthetist may be called upon urgently to secure a compromised airway immediately postpartum when no antenatal diagnosis has been made. Furthermore, after elective surgical excision, airway compromise is possible, which may again require anesthetic intervention. The aim of this study is to report the authors' experience in managing the airway in three cases of congenital cervical teratoma in the study institution over the last 24 months. These cases highlight the possible airway scenarios that may confront the anesthetist in the immediate postpartum, elective surgery and postoperative stages and the variety of techniques that may be employed in order to overcome the potential difficulties encountered.

Tramadol vs morphine during adenotonsillectomy for obstructive sleep apnea in children.

BACKGROUND: Optimal analgesia for children undergoing adenotonsillectomy for obstructive sleep apnea (OSA) is controversial. Tramadol may represent a superior choice over morphine in this group, with a potential to cause less postoperative sedation and respiratory depression. Optimal perioperative analgesia may allow expensive and time-consuming preoperative work-up and postoperative monitoring to be rationalized. METHODS: Sixty-six children were randomized to receive either perioperative tramadol or morphine in this double blinded, prospective, controlled trial. Postoperative sedation, pain, respiratory events, and vomiting were then compared between groups. RESULTS: There was no significant difference between the two groups in sedation scores 1 h after arrival in recovery (P = 0.24) or at any other time up to 6 h postoperation. There was also no evidence of a difference between the groups in pain scores up to 6 h postoperation. There were fewer episodes of postoperative desaturation (<94%) in the tramadol group up to 3 h postoperation, with 26% fewer episodes in the tramadol group during the second hour postoperation (P = 0.02). Overall, there was a trend toward fewer desaturation episodes in the tramadol group. CONCLUSIONS: Tramadol may be a suitable drug for children undergoing adenotonsillectomy for OSA. Further work is required to investigate this.