STUDY OBJECTIVES To develop evidence-based recommendations for prevention and management of infec... more STUDY OBJECTIVES To develop evidence-based recommendations for prevention and management of infections, bleeding, and local anesthetic toxicity in children undergoing regional anesthesia. DESIGN A joint committee of the European Society of Regional Anesthesia and Pain Therapy (ESRA) and the American Society of Regional Anesthesia and Pain Medicine (ASRA) studied electronic literature databases of pediatric regional anesthesia to construct evidence-based recommendations. MAIN RESULTS For epidural anesthesia lumbar or thoracic placement is preferred. Skin preparation prior to block placement with chlorhexidine is preferred to povidone iodine. A tunneled catheter technique is suggested when using the caudal route or if the epidural catheter placement is kept in situ for more than 3 days. Inspection of the epidural catheter insertion site should be performed at least once a day as part of the postoperative management. When medical and physical examination is normal, coagulation tests are usually unnecessary but if coagulation tests are abnormal, neuraxial and deep peripheral nerve blocks are contraindicated. For patients receiving Low Molecular Weight Heparin thromboprophylaxis, a safety interval of two half-lives plus the time required for heparin to reach maximal levels is considered an adequate compromise between bleeding risk and thrombosis risk when removing epidural catheters. Ultrasound-guided peripheral nerve blocks reduce the risk of vascular puncture and thus the risk of local anesthetic toxicity is reduced. CONCLUSIONS In children undergoing regional anesthesia the incidence of infection, hematoma, and local anesthetic toxicity is low. The ASRA/ESRA joint committee proposes a practice advisory to prevent and treat these complications.
Southern African Journal of Anaesthesia and Analgesia, 2008
Often called "funny looking kids" in the corridors and tearooms of medical institutions... more Often called "funny looking kids" in the corridors and tearooms of medical institutions worldwide, these children may challenge the paediatric anaesthesiologist. So what makes a child look funny? Is it the child's face or body stature that does not conform to the clinician's concept of normal? Is it that the child is too fat, too short, too tall, too hairy, too stiff, too floppy, too distorted? Or is it simply that the child has features of a genetic, metabolic, or dysmorphic syndrome that the clinician, through ignorance, labels as funny looking. Far from being funny, these disorders may have significant anaesthetic implications, and ignorance may lead to a disastrous outcome when these children undergo surgery or diagnostic procedures.
Extracted from text ... SYNDROMIC VIGNETTES IN ANAESTHESIA Southern African Journal of Anaesthesi... more Extracted from text ... SYNDROMIC VIGNETTES IN ANAESTHESIA Southern African Journal of Anaesthesia & Analgesia - July 2003 11 Anaesthesia and Beckwith - Weideman Syndrome Synopsis of patient: A 15 hour old, 4.2 kg male presents for closure of a large exomphalos. He was delivered by C-section for foetal distress after a prolonged labour at a peripheral hospital. Apgars were recorded as 6 and 8. His mother was an unmarried primigravida who attended antenatal clinic on one occasion. Meconium aspiration was suspected at birth. Preoperative assessment revealed a large term baby with features of Beckwith-Weideman syndrome - a large tongue; a faint naevus ..
Definition Local anaesthetic systemic toxicity (LAST) occurs when the plasma level of local anaes... more Definition Local anaesthetic systemic toxicity (LAST) occurs when the plasma level of local anaesthetic is high enough to cause major interference with sodium channels outside of the intended area of action (nerve block). LAST is not only caused by blocking the sodium channel but is also due to effects on other ion channels on the cell membrane (i.e. potassium and calcium channels) as well as direct negative effects on mitochondrial metabolism. High plasma levels of local anaesthetic agents may occur when administering the correct dose in the wrong place (i.e. unintended vascular injection; by rapid absorption from very vascular tissues) or the wrong dose (i.e. overdose).of LA is injected in the correct place In children LAST mainly manifests as CNS (seizures) or cardiovascular signs (ventricular arrhythmias or cardiac arrest) since the more subtle pretoxic signs or symptoms are not easily recognized under general anaesthesia or deep sedation. Incidence The reported incidence of local anesthetic systemic toxicity (LAST) in infants and children is remarkably low.1–3 Reports of vascular puncture does not always equate to LAST. Systemic toxicity requiring intervention is mostly confined to isolated case reports. Unintended vascular puncture is much more frequent but will rarely result in LAST if adequate precautions are taken. Few cases have been reported in large prospective multicentre audits. A positive test dose on the other hand is largely dependant on the type of block performed and the age of the patient. In an audited cohort from the Pediatric Regional Anesthesia Network (PRAN) database comprising a total of 26,949 blocks using a test dose, there was a 0.21% incidence of positive test doses, almost all of which occurred during caudal or epidural placement (Evidence B3).3 There were no positive test doses in other blocks with the exception of one truncal block. Test doses were less frequently utilized in non-neuraxial blocks particularly those performed under ultrasound guidance.2 An advantage of ultrasound is that the local anesthetic agent can be seen to spread outside the vessel. An audit of 104,393 blocks placed in 91,701 patients at 20 institutions in the PRAN database for LAST revealed an incidence of 0.67:10,000 (95% CI 0.29–1.4:10,000).3 Only 7 cases of seizures4 or cardiac arrest 5 after bolus administration mainly in infants 1–5 months of age were recorded. A further 12 cases with continuous infusions had minor signs of toxicity that were resolved by stopping the infusion3 4 Precautions should therefore be taken whenever a bolus dose is administered especially on top of a background infusion. Detection of LAST in children Detection, particularly in the more susceptible infants and neonates, is difficult. The majority of children are anaesthetised or sedated prior to placement of neuraxial or peripheral nerve block. General anaesthesia not only raises the threshold for LAST but also masks the classic early signs and symptoms (dizziness, somnolence, peri-oral tingling, tinnitus, metallic taste, visual disturbance). Under anaesthesia LAST manifests with ECG changes (ST segment changes, ventricular ectopy, ventricular tachycardia or ventricular fibrillation) and or signs of cardiovascular compromise (myocardial depression, reduced systemic vascular resistance). CNS manifestations (convulsions and muscle twitching) are difficult to detect under anaesthesia but are more obvious postoperatively in those with continuous infusions of local anaesthetic agents. Loss of consciousness, respiratory depression (tachypnoea, dyspnoea, cyanosis) and or cardiovascular collapse (syncope palpitations) are other manifestations of toxicity seen with continuous infusions. Prevention The risk for LAST is tied to the choice of local anaesthetic agent. Short-acting amide LA agents (e.g. carbocaine or lidocaine) are generally less toxic compared to long-acting LA.5–7 Of the long-acting local anesthetics ropivacaine and levo-bupivacaine are preferable to bupivacaine in view of their lower cardiac toxicity profile.6 Bupivacaine tends to accumulate after 48hr of continuous infusion. However no local anaesthetic is free from the risk. A 9-month-old infant developed LAST after an injection of 2-chloroprocaine (ester-type LA) into a paravertebral catheter.7 Despite 2-chloroprocaine’s rapid metabolism, being hydrolysed by plasma pseudo-choline esterases, the combination of an unusually high dose (28 mg/kg) and a likely direct intravascular injection contributed to producing LAST was noted in this report. Performing a regional anaesthetic block in a vascular location is risky and may also predispose to LAST. Based on case reports, penile blocks in infants and children are the most common block associated with LAST.8 9 Yu et al described seven cases of LAST after penile blocks.8 After revising the technique by limiting the maximum dose of racemic bupivacaine to less than 1.25 mg/kg and by directing injections laterally, away…
Southern African Journal of Anaesthesia and Analgesia, 2013
The perioperative preparation of children presenting for surgery aims to identify medical problem... more The perioperative preparation of children presenting for surgery aims to identify medical problems that might influence the outcome and to institute management strategies to reduce those risks. Adverse respiratory events remain a significant cause of morbidity and mortality in modern paediatric anaesthesia. This manuscript addresses some common medical problems that may impact on the anaesthetic. These include upper respiratory tract infections, and allergy and asthma; conditions whose optimal management should invoke daily discussions, and which can have significant implications if not managed correctly.
Southern African Journal of Anaesthesia and Analgesia, 2005
Case 1: An 11 month old boy was admitted for probing and syringing of the lacrimal ducts. He had ... more Case 1: An 11 month old boy was admitted for probing and syringing of the lacrimal ducts. He had presented with history of recurrent infections of the right eye and a mucocoele of right lacrimal sac. On examination, the patient was noted to have micrognathia, heavy eyebrows, blepharophimosis, an epicanthus, broad thumbs and clinodactyly. There was no obvious micrognathia or microstomia but he was noted to have a high arched palate. His milestones were delayed -he was not yet crawling or walking. Dentition was also delayed -he had no deciduous teeth. Clinical evaluation of the cardiovascular and respiratory systems and of the abdomen was unremarkable. Anaesthesia was induced with nitrous oxide, oxygen and halothane, and was maintained with nitrous oxide, oxygen and isoflurane. At laryngoscopy, a very high arched palate was confirmed and only the epiglottis was visible. Intubation was achieved with some difficulty using posterior displacement of the larynx and a Miller size 0 laryngoscope blade. There was no evidence of laryngomalacia although this was difficult to assess. Lacrimal duct stenosis was confirmed and probe dilated. Intraoperatively the child remained haemodynamically stable and recovery from anaesthesia was uneventful. Case 2: A 14month old boy with features of Rubinstein-Taybi syndrome (Fig ) presented with recurrent chest infections. His milestones were delayed; he was somewhat hypotonic and had a strabismus involving the left eye. .A series of investigations including a milk scan, and pH studies revealed significant oesophageal reflux. Following a further course of antibiotics and physiotherapy, he was presented for a Nissen fundoplication anti-reflux procedure. The open surgical procedure was performed under a combined general anaesthetic with halothane and a thoracic epidural (T10-11), without muscle relaxants. Laryngoscopy was made difficult by the high arched palate and relative micrognathia. The larynx was normal. Recovery from anaesthesia was unremarkable. Postoperative analgesia was provided by continuous epidural infusion which was terminated after 48 hours.
South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, 1993
A safer anaesthetic airway in paediatric adenotonsillectomy can be accomplished by using the Magi... more A safer anaesthetic airway in paediatric adenotonsillectomy can be accomplished by using the Magill oral connector as a sleeve over the orotracheal tube
South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, Jan 21, 1992
Rectal induction of anaesthesia is a useful method but is not widely used in South Africa. We stu... more Rectal induction of anaesthesia is a useful method but is not widely used in South Africa. We studied the onset of action and side-effects of 1% methohexitone administered rectally in a dose of 20 mg/kg to 110 preschool children. Ninety-one per cent were adequately sedated for inhalation induction by mask within 10 minutes, and all by 15 minutes, of drug administration. There was no evidence of significant cardiovascular or respiratory depression and only minor complications such as faecal soiling (11.8%) and hiccough (3.6%) were noted. The technique has been favourably received by parents, surgeons and nursing staff and has now become routine practice.
STUDY OBJECTIVES To develop evidence-based recommendations for prevention and management of infec... more STUDY OBJECTIVES To develop evidence-based recommendations for prevention and management of infections, bleeding, and local anesthetic toxicity in children undergoing regional anesthesia. DESIGN A joint committee of the European Society of Regional Anesthesia and Pain Therapy (ESRA) and the American Society of Regional Anesthesia and Pain Medicine (ASRA) studied electronic literature databases of pediatric regional anesthesia to construct evidence-based recommendations. MAIN RESULTS For epidural anesthesia lumbar or thoracic placement is preferred. Skin preparation prior to block placement with chlorhexidine is preferred to povidone iodine. A tunneled catheter technique is suggested when using the caudal route or if the epidural catheter placement is kept in situ for more than 3 days. Inspection of the epidural catheter insertion site should be performed at least once a day as part of the postoperative management. When medical and physical examination is normal, coagulation tests are usually unnecessary but if coagulation tests are abnormal, neuraxial and deep peripheral nerve blocks are contraindicated. For patients receiving Low Molecular Weight Heparin thromboprophylaxis, a safety interval of two half-lives plus the time required for heparin to reach maximal levels is considered an adequate compromise between bleeding risk and thrombosis risk when removing epidural catheters. Ultrasound-guided peripheral nerve blocks reduce the risk of vascular puncture and thus the risk of local anesthetic toxicity is reduced. CONCLUSIONS In children undergoing regional anesthesia the incidence of infection, hematoma, and local anesthetic toxicity is low. The ASRA/ESRA joint committee proposes a practice advisory to prevent and treat these complications.
Southern African Journal of Anaesthesia and Analgesia, 2008
Often called "funny looking kids" in the corridors and tearooms of medical institutions... more Often called "funny looking kids" in the corridors and tearooms of medical institutions worldwide, these children may challenge the paediatric anaesthesiologist. So what makes a child look funny? Is it the child's face or body stature that does not conform to the clinician's concept of normal? Is it that the child is too fat, too short, too tall, too hairy, too stiff, too floppy, too distorted? Or is it simply that the child has features of a genetic, metabolic, or dysmorphic syndrome that the clinician, through ignorance, labels as funny looking. Far from being funny, these disorders may have significant anaesthetic implications, and ignorance may lead to a disastrous outcome when these children undergo surgery or diagnostic procedures.
Extracted from text ... SYNDROMIC VIGNETTES IN ANAESTHESIA Southern African Journal of Anaesthesi... more Extracted from text ... SYNDROMIC VIGNETTES IN ANAESTHESIA Southern African Journal of Anaesthesia & Analgesia - July 2003 11 Anaesthesia and Beckwith - Weideman Syndrome Synopsis of patient: A 15 hour old, 4.2 kg male presents for closure of a large exomphalos. He was delivered by C-section for foetal distress after a prolonged labour at a peripheral hospital. Apgars were recorded as 6 and 8. His mother was an unmarried primigravida who attended antenatal clinic on one occasion. Meconium aspiration was suspected at birth. Preoperative assessment revealed a large term baby with features of Beckwith-Weideman syndrome - a large tongue; a faint naevus ..
Definition Local anaesthetic systemic toxicity (LAST) occurs when the plasma level of local anaes... more Definition Local anaesthetic systemic toxicity (LAST) occurs when the plasma level of local anaesthetic is high enough to cause major interference with sodium channels outside of the intended area of action (nerve block). LAST is not only caused by blocking the sodium channel but is also due to effects on other ion channels on the cell membrane (i.e. potassium and calcium channels) as well as direct negative effects on mitochondrial metabolism. High plasma levels of local anaesthetic agents may occur when administering the correct dose in the wrong place (i.e. unintended vascular injection; by rapid absorption from very vascular tissues) or the wrong dose (i.e. overdose).of LA is injected in the correct place In children LAST mainly manifests as CNS (seizures) or cardiovascular signs (ventricular arrhythmias or cardiac arrest) since the more subtle pretoxic signs or symptoms are not easily recognized under general anaesthesia or deep sedation. Incidence The reported incidence of local anesthetic systemic toxicity (LAST) in infants and children is remarkably low.1–3 Reports of vascular puncture does not always equate to LAST. Systemic toxicity requiring intervention is mostly confined to isolated case reports. Unintended vascular puncture is much more frequent but will rarely result in LAST if adequate precautions are taken. Few cases have been reported in large prospective multicentre audits. A positive test dose on the other hand is largely dependant on the type of block performed and the age of the patient. In an audited cohort from the Pediatric Regional Anesthesia Network (PRAN) database comprising a total of 26,949 blocks using a test dose, there was a 0.21% incidence of positive test doses, almost all of which occurred during caudal or epidural placement (Evidence B3).3 There were no positive test doses in other blocks with the exception of one truncal block. Test doses were less frequently utilized in non-neuraxial blocks particularly those performed under ultrasound guidance.2 An advantage of ultrasound is that the local anesthetic agent can be seen to spread outside the vessel. An audit of 104,393 blocks placed in 91,701 patients at 20 institutions in the PRAN database for LAST revealed an incidence of 0.67:10,000 (95% CI 0.29–1.4:10,000).3 Only 7 cases of seizures4 or cardiac arrest 5 after bolus administration mainly in infants 1–5 months of age were recorded. A further 12 cases with continuous infusions had minor signs of toxicity that were resolved by stopping the infusion3 4 Precautions should therefore be taken whenever a bolus dose is administered especially on top of a background infusion. Detection of LAST in children Detection, particularly in the more susceptible infants and neonates, is difficult. The majority of children are anaesthetised or sedated prior to placement of neuraxial or peripheral nerve block. General anaesthesia not only raises the threshold for LAST but also masks the classic early signs and symptoms (dizziness, somnolence, peri-oral tingling, tinnitus, metallic taste, visual disturbance). Under anaesthesia LAST manifests with ECG changes (ST segment changes, ventricular ectopy, ventricular tachycardia or ventricular fibrillation) and or signs of cardiovascular compromise (myocardial depression, reduced systemic vascular resistance). CNS manifestations (convulsions and muscle twitching) are difficult to detect under anaesthesia but are more obvious postoperatively in those with continuous infusions of local anaesthetic agents. Loss of consciousness, respiratory depression (tachypnoea, dyspnoea, cyanosis) and or cardiovascular collapse (syncope palpitations) are other manifestations of toxicity seen with continuous infusions. Prevention The risk for LAST is tied to the choice of local anaesthetic agent. Short-acting amide LA agents (e.g. carbocaine or lidocaine) are generally less toxic compared to long-acting LA.5–7 Of the long-acting local anesthetics ropivacaine and levo-bupivacaine are preferable to bupivacaine in view of their lower cardiac toxicity profile.6 Bupivacaine tends to accumulate after 48hr of continuous infusion. However no local anaesthetic is free from the risk. A 9-month-old infant developed LAST after an injection of 2-chloroprocaine (ester-type LA) into a paravertebral catheter.7 Despite 2-chloroprocaine’s rapid metabolism, being hydrolysed by plasma pseudo-choline esterases, the combination of an unusually high dose (28 mg/kg) and a likely direct intravascular injection contributed to producing LAST was noted in this report. Performing a regional anaesthetic block in a vascular location is risky and may also predispose to LAST. Based on case reports, penile blocks in infants and children are the most common block associated with LAST.8 9 Yu et al described seven cases of LAST after penile blocks.8 After revising the technique by limiting the maximum dose of racemic bupivacaine to less than 1.25 mg/kg and by directing injections laterally, away…
Southern African Journal of Anaesthesia and Analgesia, 2013
The perioperative preparation of children presenting for surgery aims to identify medical problem... more The perioperative preparation of children presenting for surgery aims to identify medical problems that might influence the outcome and to institute management strategies to reduce those risks. Adverse respiratory events remain a significant cause of morbidity and mortality in modern paediatric anaesthesia. This manuscript addresses some common medical problems that may impact on the anaesthetic. These include upper respiratory tract infections, and allergy and asthma; conditions whose optimal management should invoke daily discussions, and which can have significant implications if not managed correctly.
Southern African Journal of Anaesthesia and Analgesia, 2005
Case 1: An 11 month old boy was admitted for probing and syringing of the lacrimal ducts. He had ... more Case 1: An 11 month old boy was admitted for probing and syringing of the lacrimal ducts. He had presented with history of recurrent infections of the right eye and a mucocoele of right lacrimal sac. On examination, the patient was noted to have micrognathia, heavy eyebrows, blepharophimosis, an epicanthus, broad thumbs and clinodactyly. There was no obvious micrognathia or microstomia but he was noted to have a high arched palate. His milestones were delayed -he was not yet crawling or walking. Dentition was also delayed -he had no deciduous teeth. Clinical evaluation of the cardiovascular and respiratory systems and of the abdomen was unremarkable. Anaesthesia was induced with nitrous oxide, oxygen and halothane, and was maintained with nitrous oxide, oxygen and isoflurane. At laryngoscopy, a very high arched palate was confirmed and only the epiglottis was visible. Intubation was achieved with some difficulty using posterior displacement of the larynx and a Miller size 0 laryngoscope blade. There was no evidence of laryngomalacia although this was difficult to assess. Lacrimal duct stenosis was confirmed and probe dilated. Intraoperatively the child remained haemodynamically stable and recovery from anaesthesia was uneventful. Case 2: A 14month old boy with features of Rubinstein-Taybi syndrome (Fig ) presented with recurrent chest infections. His milestones were delayed; he was somewhat hypotonic and had a strabismus involving the left eye. .A series of investigations including a milk scan, and pH studies revealed significant oesophageal reflux. Following a further course of antibiotics and physiotherapy, he was presented for a Nissen fundoplication anti-reflux procedure. The open surgical procedure was performed under a combined general anaesthetic with halothane and a thoracic epidural (T10-11), without muscle relaxants. Laryngoscopy was made difficult by the high arched palate and relative micrognathia. The larynx was normal. Recovery from anaesthesia was unremarkable. Postoperative analgesia was provided by continuous epidural infusion which was terminated after 48 hours.
South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, 1993
A safer anaesthetic airway in paediatric adenotonsillectomy can be accomplished by using the Magi... more A safer anaesthetic airway in paediatric adenotonsillectomy can be accomplished by using the Magill oral connector as a sleeve over the orotracheal tube
South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, Jan 21, 1992
Rectal induction of anaesthesia is a useful method but is not widely used in South Africa. We stu... more Rectal induction of anaesthesia is a useful method but is not widely used in South Africa. We studied the onset of action and side-effects of 1% methohexitone administered rectally in a dose of 20 mg/kg to 110 preschool children. Ninety-one per cent were adequately sedated for inhalation induction by mask within 10 minutes, and all by 15 minutes, of drug administration. There was no evidence of significant cardiovascular or respiratory depression and only minor complications such as faecal soiling (11.8%) and hiccough (3.6%) were noted. The technique has been favourably received by parents, surgeons and nursing staff and has now become routine practice.
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