- Email: [email protected]
Perioperative respiratory complications in children
Comment
Perioperative respiratory complications in children
www.thelancet.com Vol 376 September 4, 2010
basis, such as asthma or gastroeosphageal reflux, as its cause.6–8 The unexpected frequency of nocturnal cough and its association with intraoperative bronchospasm in today’s study suggests that the cough might have had an organic basis, which warranted further investigation and treatment. Fifth, children with obstructive sleep apnoea and nocturnal haemoglobin desaturation (<85%) were not identified as being at increased risk for perioperative respiratory adverse events even though ear, nose, and throat surgery was common.9,10 Sixth, the greater frequency of perioperative respiratory adverse events in children who were treated with sevoflurane compared with those treated with propofol is interesting and curious, but is supported by evidence.11 Most anaesthetists are well versed in using sevoflurane for induction of anaesthesia and might be surprised by these findings, although one should anticipate a reduced frequency of perioperative respiratory adverse events after intravenous induction of anaesthesia than after inhalational induction, even when a minimally noxious agent such as sevoflurane is used. A large, prospective, observational study is a formidable proposition, and limiting the enrolment to one institution was reasonable. Von Ungern-Sternberg and colleagues wisely minimised observers’ and operators’ bias by withholding the study hypothesis from the anaesthetists, a strategy that is not widely exploited in clinical research. The investigators used the ISAAC questionnaire to collect the historical data, even though this questionnaire has never been properly validated. The advantages of a single-
See Articles page 773
Science Photo Library
Respiratory events are a major risk for perioperative morbidity and cause 30% of perioperative cardiac arrests in children.1 In The Lancet today, Britta von UngernSternberg and colleagues2 present a prospective cohort of more than 9000 children who had had general anaesthesia in a single children’s hospital. The investigators evaluated specific details in the children’s history (with the International Study Group for Asthma and Allergies in Childhood [ISAAC] questionnaire), demographic data, and anaesthetic management, and correlated these variables with occurrence of perioperative respiratory adverse events.2 Multivariate analysis showed that airway sensitivity, eczema, a family history of airway disorders, and anaesthetic management statistically contributed to the risk of such events. Although today’s results are mostly consistent with previous studies, they do raise questions. First, is the practice described in today’s study consistent with most urban paediatric anaesthetic practices? For children with upper respiratory tract infections who present with a temperature of more than 38°C, a change in behaviour, mucopurulent airway sections, or lower respiratory tract signs such as wheezing that does not clear with a deep cough, surgery is usually cancelled before anaesthesia and rescheduled, particularly if the upper respiratory tract infection started less than 2 weeks ago.3 In von Ungern-Sternberg and colleagues’ study, surgery for children with two of these factors—high temperature and green runny nose—was not cancelled and unsurprisingly these children developed perioperative respiratory adverse events. This non-cancellation of surgery might reflect the unusual geodemographic referral pattern for paediatric anaesthesia in Western Australia. Second, I treat a clear runny nose (rhinorrhoea) preoperatively with a nasal vasoconstrictor to assuage its effect on the airways (this method is based on my 30 years’ experience and is not evidence-based).4 In today’s study, there was no mention about whether rhinorrhoea was treated preoperatively, and this sign proved to be a significant risk factor for laryngospasm and perioperative respiratory adverse events.2 Third, I wonder whether medical management of the children with asthma and allergies was optimised preoperatively.4,5 Optimisation would certainly have affected the results, although the assumption is that all children were in optimum shape. Fourth, a chronic (nocturnal) cough might have an organic
745
Comment
institution study include consistent, uniform, and complete data collection, and the ability to verify all complications; the main disadvantage is that the external validity of the results might be limited. Indeed, the anaesthetic practice in this single institution seems to partly differ from my practice, and probably from other urban paediatric anaesthetic practices. Nonetheless, many of the findings are consistent with our experiences—the frequency of laryngospasm decreases with increasing age, and secondhand smoke and airway manipulation independently increase the risk of perioperative respiratory adverse events. Today’s study adds an interesting perspective to our understanding of perioperative respiratory adverse events in a cross-section of children undergoing surgery, although its external validity might be challenged and the reproducibility of several findings requires further research. Optimising anaesthetic care for children includes identifying risk factors for complications, and providing the best preoperative medical management and the best anaesthetic care. In the hands of experienced paediatric anaesthetists, perioperative respiratory adverse events rarely lead to serious perioperative morbidity, admission to hospital or the intensive care unit, cardiac arrest, or death. One might even suggest that perioperative respiratory adverse events (as defined in today’s study) that do not result in serious outcomes are surrogate outcome markers of clinically minimal importance. If the absence of any unanticipated hospital admission and death in today’s study means that none truly occurred, the frequency of serious morbidity in this study was less than 0/9297.1,12,13 Although this statistic is consistent with a global risk for children undergoing general anaesthesia, it might not reflect specific subpopulations of atrisk infants and children (such as those with obstructive sleep apnoea or cardiac disease) or specific management strategies
because this was an observational study. Randomised trials are required to evaluate and validate the contributions of some subpopulations and management strategies to the frequency of perioperative respiratory adverse events.
Jerrold Lerman Department of Anesthesia, Women and Children’s Hospital of Buffalo, Buffalo, NY 14222, USA [email protected] I declare that I have no conflicts of interest. 1
2
3 4
5
6 7 8
9
10
11
12
13
Bhananker SM, Ramamoorthy C, Geiduschek JM, et al. Anesthesia-related cardiac arrest in children: update from the Pediatric Perioperative Cardiac Arrest Registry. Anesth Analg 2007; 105: 344–50. von Ungern-Sternberg BS, Boda K, Chambers NA, et al. Risk assessment for respiratory complications in paediatric anesthesia: a prospective cohort study. Lancet 2010; 378: 773–83. Tait AR, Malviya S. Anesthesia for the child with an upper respiratory tract infection: still a dilemma? Anesth Analg 2005; 100: 59–65. Lerman J, Coté CJ, Steward DJ. Medical conditions influencing anesthetic management. Manual of pediatric anesthesia: with an index of pediatric syndromes, 6th edn. New York: Elsevier Health Sciences, 2010: 171–213. von Ungern-Sternberg BS, Habre W, Erb TO, Heaney M. Salbutamol premedication in children with a recent respiratory tract infection. Pediatr Anesth 2009; 19: 1064–69. Mvula M, Larzelere M, Kraus M, et al. Prevalence of asthma and asthma-like symptoms in inner-city schoolchildren. J Asthma 2005; 42: 9–16. de Jongste JC, Shields MD. Cough·2: chronic cough in children. Thorax 2003; 58: 998–1003. Shields MD, Bush A, Everard ML, McKenzie S, Primhak R, for the British Thoracic Society Cough Guideline Group. BTS guidelines: recommendations for the assessment and management of cough in children. Thorax 2008; 63 (suppl 3): iii1–15. Brown KA, Laferrière A, Moss IR. Recurrent hypoxemia in young children with obstructive sleep apnea is associated with reduced opioid requirement for analgesia. Anesthesiology 2004; 100: 806–10. Raghavendran S, Bagry H, Detheux G, Zhang X, Brouillette RT, Brown KA. An anesthetic management protocol to decrease respiratory complications after adenotonsillectomy in children with severe sleep apnea. Anesth Analg 2010; 110: 1093–101. Oberer C, von Ungern-Sternberg BS, Frei FJ, Erb TO. Respiratory reflex responses of the larynx differ between sevoflurane and propofol in pediatric patients. Anesthesiology 2005; 103: 1142–48. Flick RP, Sprung J, Harrison TE, et al. Perioperative cardiac arrests in children between 1988 and 2005 at a tertiary referral center: a study of 92 881 patients. Anesthesiology 2007; 106: 226–37. Bharti N, Batra YK, Kaur H. Paediatric perioperative cardiac arrest and its mortality: database of a 60-month period from a tertiary paediatric centre. Eur J Anaesthiol 2009; 26: 490–95.
Refractory breathlessness: oxygen or room air? See Articles page 784
746
Breathlessness is a frightening and devastating symptom which affects patients with many diseases in advanced stages. The prevalence reaches 90% in cancer, 95% in chronic obstructive pulmonary disease (COPD), 88% in cardiac failure,1 and 80% in advanced-stage renal disease.2 Patients with various neurological conditions also become breathless.3,4 Oxygen therapy is often used to manage breathlessness. However, although there is accepted evidence for using oxygen in patients
with COPD and hypoxaemia,5 palliative oxygen is often used in patients with advanced life-limiting illness, irrespective of the partial pressure of oxygen in arterial blood (PaO2). Three systematic reviews raised concerns about a lack of robust evidence with trials that were underpowered, inadequately controlled, or had unclear outcomes.6–8 In The Lancet today, Amy Abernethy and colleagues9 report a double-blind randomised trial to evaluate the www.thelancet.com Vol 376 September 4, 2010
Perioperative respiratory complications in children
www.thelancet.com Vol 376 September 4, 2010
basis, such as asthma or gastroeosphageal reflux, as its cause.6–8 The unexpected frequency of nocturnal cough and its association with intraoperative bronchospasm in today’s study suggests that the cough might have had an organic basis, which warranted further investigation and treatment. Fifth, children with obstructive sleep apnoea and nocturnal haemoglobin desaturation (<85%) were not identified as being at increased risk for perioperative respiratory adverse events even though ear, nose, and throat surgery was common.9,10 Sixth, the greater frequency of perioperative respiratory adverse events in children who were treated with sevoflurane compared with those treated with propofol is interesting and curious, but is supported by evidence.11 Most anaesthetists are well versed in using sevoflurane for induction of anaesthesia and might be surprised by these findings, although one should anticipate a reduced frequency of perioperative respiratory adverse events after intravenous induction of anaesthesia than after inhalational induction, even when a minimally noxious agent such as sevoflurane is used. A large, prospective, observational study is a formidable proposition, and limiting the enrolment to one institution was reasonable. Von Ungern-Sternberg and colleagues wisely minimised observers’ and operators’ bias by withholding the study hypothesis from the anaesthetists, a strategy that is not widely exploited in clinical research. The investigators used the ISAAC questionnaire to collect the historical data, even though this questionnaire has never been properly validated. The advantages of a single-
See Articles page 773
Science Photo Library
Respiratory events are a major risk for perioperative morbidity and cause 30% of perioperative cardiac arrests in children.1 In The Lancet today, Britta von UngernSternberg and colleagues2 present a prospective cohort of more than 9000 children who had had general anaesthesia in a single children’s hospital. The investigators evaluated specific details in the children’s history (with the International Study Group for Asthma and Allergies in Childhood [ISAAC] questionnaire), demographic data, and anaesthetic management, and correlated these variables with occurrence of perioperative respiratory adverse events.2 Multivariate analysis showed that airway sensitivity, eczema, a family history of airway disorders, and anaesthetic management statistically contributed to the risk of such events. Although today’s results are mostly consistent with previous studies, they do raise questions. First, is the practice described in today’s study consistent with most urban paediatric anaesthetic practices? For children with upper respiratory tract infections who present with a temperature of more than 38°C, a change in behaviour, mucopurulent airway sections, or lower respiratory tract signs such as wheezing that does not clear with a deep cough, surgery is usually cancelled before anaesthesia and rescheduled, particularly if the upper respiratory tract infection started less than 2 weeks ago.3 In von Ungern-Sternberg and colleagues’ study, surgery for children with two of these factors—high temperature and green runny nose—was not cancelled and unsurprisingly these children developed perioperative respiratory adverse events. This non-cancellation of surgery might reflect the unusual geodemographic referral pattern for paediatric anaesthesia in Western Australia. Second, I treat a clear runny nose (rhinorrhoea) preoperatively with a nasal vasoconstrictor to assuage its effect on the airways (this method is based on my 30 years’ experience and is not evidence-based).4 In today’s study, there was no mention about whether rhinorrhoea was treated preoperatively, and this sign proved to be a significant risk factor for laryngospasm and perioperative respiratory adverse events.2 Third, I wonder whether medical management of the children with asthma and allergies was optimised preoperatively.4,5 Optimisation would certainly have affected the results, although the assumption is that all children were in optimum shape. Fourth, a chronic (nocturnal) cough might have an organic
745
Comment
institution study include consistent, uniform, and complete data collection, and the ability to verify all complications; the main disadvantage is that the external validity of the results might be limited. Indeed, the anaesthetic practice in this single institution seems to partly differ from my practice, and probably from other urban paediatric anaesthetic practices. Nonetheless, many of the findings are consistent with our experiences—the frequency of laryngospasm decreases with increasing age, and secondhand smoke and airway manipulation independently increase the risk of perioperative respiratory adverse events. Today’s study adds an interesting perspective to our understanding of perioperative respiratory adverse events in a cross-section of children undergoing surgery, although its external validity might be challenged and the reproducibility of several findings requires further research. Optimising anaesthetic care for children includes identifying risk factors for complications, and providing the best preoperative medical management and the best anaesthetic care. In the hands of experienced paediatric anaesthetists, perioperative respiratory adverse events rarely lead to serious perioperative morbidity, admission to hospital or the intensive care unit, cardiac arrest, or death. One might even suggest that perioperative respiratory adverse events (as defined in today’s study) that do not result in serious outcomes are surrogate outcome markers of clinically minimal importance. If the absence of any unanticipated hospital admission and death in today’s study means that none truly occurred, the frequency of serious morbidity in this study was less than 0/9297.1,12,13 Although this statistic is consistent with a global risk for children undergoing general anaesthesia, it might not reflect specific subpopulations of atrisk infants and children (such as those with obstructive sleep apnoea or cardiac disease) or specific management strategies
because this was an observational study. Randomised trials are required to evaluate and validate the contributions of some subpopulations and management strategies to the frequency of perioperative respiratory adverse events.
Jerrold Lerman Department of Anesthesia, Women and Children’s Hospital of Buffalo, Buffalo, NY 14222, USA [email protected] I declare that I have no conflicts of interest. 1
2
3 4
5
6 7 8
9
10
11
12
13
Bhananker SM, Ramamoorthy C, Geiduschek JM, et al. Anesthesia-related cardiac arrest in children: update from the Pediatric Perioperative Cardiac Arrest Registry. Anesth Analg 2007; 105: 344–50. von Ungern-Sternberg BS, Boda K, Chambers NA, et al. Risk assessment for respiratory complications in paediatric anesthesia: a prospective cohort study. Lancet 2010; 378: 773–83. Tait AR, Malviya S. Anesthesia for the child with an upper respiratory tract infection: still a dilemma? Anesth Analg 2005; 100: 59–65. Lerman J, Coté CJ, Steward DJ. Medical conditions influencing anesthetic management. Manual of pediatric anesthesia: with an index of pediatric syndromes, 6th edn. New York: Elsevier Health Sciences, 2010: 171–213. von Ungern-Sternberg BS, Habre W, Erb TO, Heaney M. Salbutamol premedication in children with a recent respiratory tract infection. Pediatr Anesth 2009; 19: 1064–69. Mvula M, Larzelere M, Kraus M, et al. Prevalence of asthma and asthma-like symptoms in inner-city schoolchildren. J Asthma 2005; 42: 9–16. de Jongste JC, Shields MD. Cough·2: chronic cough in children. Thorax 2003; 58: 998–1003. Shields MD, Bush A, Everard ML, McKenzie S, Primhak R, for the British Thoracic Society Cough Guideline Group. BTS guidelines: recommendations for the assessment and management of cough in children. Thorax 2008; 63 (suppl 3): iii1–15. Brown KA, Laferrière A, Moss IR. Recurrent hypoxemia in young children with obstructive sleep apnea is associated with reduced opioid requirement for analgesia. Anesthesiology 2004; 100: 806–10. Raghavendran S, Bagry H, Detheux G, Zhang X, Brouillette RT, Brown KA. An anesthetic management protocol to decrease respiratory complications after adenotonsillectomy in children with severe sleep apnea. Anesth Analg 2010; 110: 1093–101. Oberer C, von Ungern-Sternberg BS, Frei FJ, Erb TO. Respiratory reflex responses of the larynx differ between sevoflurane and propofol in pediatric patients. Anesthesiology 2005; 103: 1142–48. Flick RP, Sprung J, Harrison TE, et al. Perioperative cardiac arrests in children between 1988 and 2005 at a tertiary referral center: a study of 92 881 patients. Anesthesiology 2007; 106: 226–37. Bharti N, Batra YK, Kaur H. Paediatric perioperative cardiac arrest and its mortality: database of a 60-month period from a tertiary paediatric centre. Eur J Anaesthiol 2009; 26: 490–95.
Refractory breathlessness: oxygen or room air? See Articles page 784
746
Breathlessness is a frightening and devastating symptom which affects patients with many diseases in advanced stages. The prevalence reaches 90% in cancer, 95% in chronic obstructive pulmonary disease (COPD), 88% in cardiac failure,1 and 80% in advanced-stage renal disease.2 Patients with various neurological conditions also become breathless.3,4 Oxygen therapy is often used to manage breathlessness. However, although there is accepted evidence for using oxygen in patients
with COPD and hypoxaemia,5 palliative oxygen is often used in patients with advanced life-limiting illness, irrespective of the partial pressure of oxygen in arterial blood (PaO2). Three systematic reviews raised concerns about a lack of robust evidence with trials that were underpowered, inadequately controlled, or had unclear outcomes.6–8 In The Lancet today, Amy Abernethy and colleagues9 report a double-blind randomised trial to evaluate the www.thelancet.com Vol 376 September 4, 2010