Anaesthesia, Pain, Intensive Care and Emergency - Part 9 ppsx

Initial evaluation International guidelines in 2000 included five questions (Term gestation? Amnio- tic fluid clear? Breathing or crying? Good muscle tone? Pink?) for the initial evaluation of each neonate [2–4]. These questions had to be asked within the first 30 s of each infant’s life, and the answers determined whether the neonate would receive “routine” or “intensive” care. In the international guidelines issued in 2005 [5] the colour of the patient(pink?) isnotconsideredinthis phase.Inarecentstudy, Kramlin et al. evaluated transcutaneous SaO 2 in 175 “healthy” neonates (gestational age 38 +3 weeks; birth weight 2,953+865) during the first 5 min of postnatal life [12]. At 1 min of life the median (interquartile range) trancutaneous SaO 2 values were 63% (53–68%), confirming that clinical oxygenation (pink?) is not useful for the initial evaluation of the patient. Meconium aspiration syndrome Meconium aspiration syndrome (MAS) is frequently encountered in the delivery room [2–5]. In the presence of meconium-stained infants, the original guidelines suggested performing (a) suction of the nose, mouth and posterior pharynx before delivery of the shoulders, (b) direct laryngoscopy immediately after birth for suctioning of residual meconium from the hypopharynx and (c) intubation/suc- tion of the trachea [2–4]. However, previous studies demonstrated that tracheal suctioning of the vigorous infant with meconium-stained fluid did not improve outcome and could cause complications [13]. The 2000 guidelines stated that intubation of the trachea in meconium-stained infants must be limited to patients with “absent or depressed respirations, decreased muscle tone, or heart rate <100 bpm” [2–4]. A recent randomised multicentre study demonstrated that the suction of mouth, nose and posterior pharynx before the delivery of the infant’s shoulders did not change the incidence of MAS (relative risk 0.9, CI 0.6–1.3) [14]. Based on this study, the international guidelines of 2005 “No longer advise routine intrapartum oropharyngeal and nasopharyngeal suctioning for infants born to mothers with meconium staining of amniotic fluid” [5]. Temperature The accepted standard for preterm infants and nonasphyxiated term infants is an environment that provides minimal heat loss and metabolic oxygen consumption. The Guidelines for Perinatal Care suggest that the environmental temperature in newborn care areas should be kept at 23.8–26.1°C [15]. A recent study showed that in Italy half of the level III centres fail to reach this standard [16]. Instead, a few centres are using the method of wrapping the infant’s trunk in a polyethylene membrane to lower heat loss [16]. This method was demonstrated to be effective Resuscitation of the newborn 379 in preventing heat loss evaporation in ELBWI by Vohra et al. and has already become part of clinical management in this high-risk population [17]. For this reason, international guidelines 2005 recommend that “additional warming tech- niques be used, such as covering the infant in plastic wrapping (food-grade, heat-resistant plastic) and placing him or her under radiant heat” [5]. On the other hand, guidelines advise avoiding hyperthermia, because animal studies indicate that this condition during and after ischaemia is associated with progression of cerebral injury [5, 18]. Finally, although animal and human studies seem to be promising in terms of brain damage prevention [19, 20], there is too little information available to justify recommending routine application of modest systemic or selective cerebral hypo- thermia after resuscitation of infants with suspected asphyxia. Administration of oxygen “Old” guidelines for neonatal resuscitation recommended provision of 100% oxy- gen at delivery [2–4]. Clinical studies have shown that room air is as effective as 100% oxygen for resuscitation of asphyxiated newborns and reduces the oxidative stress [21–23]. A meta-analysis of four human studies showed a reduction in mortality rate and no evidence of harm in infants resuscitated with room air compared with those resuscitated with 100% oxygen, although these results should be viewed with caution because of significant methodological concerns [24]. In a national survey, almost half the centres (44.6%) used oxygen concentra- tions lower than 100% for resuscitation of ELBWIs, showing a deviation from the NRP guidelines [25]. These data were comparable to those reported by O’Donnell et al. in a recent survey involving neonatologists from 13 countries [26]. Although the results of experimental and clinical studies suggest that it may be desirable to use lower oxygen concentrations [21–23], the 2005 guidelines state that “the standard approach to resuscitation is to use 100% oxygen” [5]. However, for the first time, they consider the possibility of using oxygen concentrations lower than 100%: “There is evidence that employing either of these practices (room air or 100% oxygen) during resuscitation of neonates is reasonable.” A recent study shows that pulse oxim etry has not become an accepted standard of care during neonatal resuscitation [25]. Instead, a more aggressive use of the pulse oximeter in the delivery setting may facilitate the achievement of adequate blood oxygen levels, avoiding hyperoxia throughout and beyond the resuscitation process. The “new” guidelines consider the use of pulse oximetry to guide adminis- tration of a variable concentration of oxygen in the delivery room setting [5]. Positive pressure ventilation The recommendations for assisted ventilation are similar to those in previous guidelines: initial peak inflating pressures of 30–40 cmH 2 O at a rate of 40–60 380 D. Trevisanuto, N. Doglioni, F. Mario breaths per minute [2–5]. Furthermore, the guidelines of 2005 outlined that “There is insufficient evidence to recommend an optimum inflation time” [5]. Self-infla - ting and flow-inflating bag-and-m ask eq uipment and techniques remain the corn erstone of achieving eff ective ventilation in most resuscitation s. However, for the first time, in the new guidelines the flo w-con trolled pressu re-limited mecha- nical devices (e.g. T-piece resuscitators) are recognised as an acceptable method of administering positive-pressure ventilation during resuscitation of the newly born, and in particular the premature infant [5]. With regard to preterm neonates, previous guidelines did not make a distinc- tion between the respiratory support desirable for term and/or very premature infants [2–4]. Owing to the aetiology of the respiratory failure, it is reasonable to postulate that very preterm infants may need a different resuscitation management than term infants [10, 27–31]. The guidelines of 2005 dedicate a specific chapter to assisted ventilation of preterm infants [5]. Although the level of evidence remains low or indeterminate for these statements, the following indications are reported: inclusion of positive end-expiratory pressure during application of positive-pres- sure ventilation, monitoring of administered pressures (initial inflation pressure of 20–25 cmH 2 O) and use of continuous positive airway pressure in spontaneously breathing preterm infants after resuscitation [5]. The 2005 Guidelinesstatethatend otrachealintubationmayb eind icatedforspecial circumstances such as congenital diaphragmaticherniaorELBWI , suggestingthatthis procedure is mandatory for these groups of patients [5]. Some experts advocate the intubation of all the VLBWI at delivery [2–4]; however, recent studies suggest that individualised intubation strategy is superior in this group of neonates [28, 29]. Furthermore, a recent survey showed that the intubation policy for ELBWI is based on an individualised strategy for the majority of the Italian centres (86.4%) [25]. Medications The recommendations of 2005 changed for two drugs traditionally used for neo- natal resuscitation [5]. First, based on the route of administration (IV or endotra- cheal), the dose of epinephrine was modified. In fact, if the endotracheal route is used, epinephrine doses of 0.01–0.03 mg/kg will probably be ineffective. Therefore, with 0.01–0.03 mg/kg per dose IV administration is the preferred route. While access is being obtained, administration of a higher dose (up to 0.1 mg/kg) through the endotracheal tube may be considered, but the safety and efficacy ofthispractice have not been evaluated. Second, the guidelines of 2005 stated that “Naloxone is not recommended during the primary steps of resuscitation” [5]. Furthermore, as there are no studies reporting the efficacy of endotracheal naloxone, this route is not recommended at this point. Resuscitation of the newborn 381 Withholding and discontinuing resuscitation Guidelines 2005 state that “A consistent and coordinated approach to individual cases by the obstetric and neonatal teams and the parents is an important goal” [5]. However, recent studies show that hospitals frequently have no written protocols for ethical aspects of neonatal resuscitation, the final decision is taken by the attending physician, and the parent’s wishes are not adequately taken into account [32, 33]. Previous guidelines suggested that in particular circumstances it was reasonable to withhold resuscitation [2–4]. They included extreme prematurity, (gestational age <23 weeks or birth weight <400 g), anencephaly, and chromoso- mal abnormalities incompatible with life, such as trisomy 13 or 18. In the latest recommendations, all these circum stances are confirmed with the exception of trisomy 18 [5]. Based on previous guidelines [2–4], it was thought justified to discontinue resuscitation after 15 min of continuous and adequate resuscitative efforts when faced with infants showing no signs of life (no heart beat and no respiratory effort).In these circumstances, Guidelines 2005limitthistimeto10min [5]. In Italy, 31.8% of the level III neonatal centres have no defined time for discontinuation of resuscitative efforts when faced with this clinical situation [32]. In conclusion, based on the results of recent randomised clinical trials, current guidelines for neonatal resuscitation have been changed. However, the level of evidence of some recommendations remains low, suggesting that further prospec- tive research in this field is needed. References 1. Saugstad OD (1998) Practical aspects of resuscitating asphyxiated newborn infants. Eur J Pediatr 157 Suppl 1:S11–15 2. Kattwinkel J (2000) Neonatal resuscitation program—Textbook of neonatal resuscita- tion, 4th edn. American Academy of Pediatrics/American Heart Association 3. Kattwinkel J, Niermeyer S, Nadkarmi et al (1999) ILCOR advisory statement: resusci- tation of the newly born infant. Pediatrics 103:e56 4. Contributors and Reviewers for the Neonatal Resuscitation Guidelines (2000) Interna- tional guidelines for neonatal resuscitation: an excerpt from the guidelines 2000 for cardiopulmonary resuscitation and emergency cardiovascular care: international con- sensus on science. Pediatrics 106:e29 5. American Heart Association, American Academy of Pediatrics (2006) 2005 American Heart Association (AHA) Guidelines for cardiopulmonary resuscitation (CRP) and emergency cardiovascular care of pediatric and neonatal patients: neonatal resuscita- tion guidelines. Pediatrics 117:e1029–1038 6. Milner AD (1998) Resuscitation at birth. Eur J Pediatr 157:524–527 7. Soll R (1999) Consensus and controversy over resuscitation of the newborn infant. Lancet 354:4–5 8. Silverman WA (2004) A cautionary tale about supplemental oxygen: the albatross of neonatal medicine. Pediatrics 113:304–306 9. Kattwinkel J (2003) Evaluating resuscitation practices on the basis of evidence: the findings at first glance may seem illogical. J Pediatr 142:221–222 382 D. Trevisanuto, N. Doglioni, F. Mario 10. O’Donnell CPF. Davis PG, Morley CJ (2003) Resuscitation of premature infants: what are we doing wrong and can we do better? Biol Neonate 84:76–82 11. Carbine DN, Finer NN, Knodel E et al (2000)Video recording as a means of evaluating neonatal resuscitation performance. Pediatrics 106:654–658 12. Kramlin CO, O’Donnell CP, Davis PG et al (2006) Oxygen saturation in healthy infants immediately after birth. J Pediatr 148:585–589 13. Wiswell TE, Gannon CM, Jacob J et al (2000) Delivery room management of apparently vigorous meconium-stained neonate: results of the multicenter, international collabo- rative trial. Pediatrics 105:1–7 14. Vain NE, Szyld EG, Prudent LM et al (2004) Oropharyngeal and nasopharyngeal suctioning of meconium-stained neonates before delivery of their shoulders: multicen- ter, randomised conrolled trial. Lancet 364:597–602 15. American Academy of Pediatrics, American College of Obstetricians andGynecologists (1997) Impatient perinatal care services. In: Guidelines for perinatal care, 4th edn. AmericanAcademy ofPediatrics/AmericanCollege ofObstetriciansand Gynecologists, pp 13–50 16. Trevisanuto D, Doglioni N, Ferrarese P et al (2005) Thermal management of extremely low birth weight infants at birth. J Pediatr 147:716–717 17. Vohra S, Roberts RS, Zhang B et al (2004) Heat Loss Prevention (HeLP) in the delivery room: a randomized controlled trial of polyethylene occlusive skin wrapping in very preterm infants. J Pediatr 145:750–753 18. Coimbra C, Boris-Moller F, Drake M et al (1996) Diminished neuronal damage in the rat brain by late treatment with the antipyretic drug dipyrone or cooling following cerebral ischemia. Acta Neuropathol (Berl) 92:447–453 19. Gluckman PD, Wyatt JS, Azzopardi D et al (2005) Selective head cooling with mild systemic hypothermia after neonatal encephalopathy: multicentre randomised trial. Lancet 365:663–670 20. Donovan EF, Fanaroff AA, Poole WK et al (2005) Whole-body hypothermia for neona- tes with hypoxic-ischemic encephalopathy. N Engl J Med 353:1574–1584 21. SaugstadOD, Rootwelt T,Aalen O(1998). Resuscitation ofasphyxiatednewborn infants withroom air oroxygen: Aninternational controlledtrial: TheResair2 study.Pediatrics 102:e1 22. Saugstad OD, Ramji S, Irani SF (2003) Resuscitation of newborn infants with 21% or 100% oxygen: follow-up at 18 to 24 months. Pediatrics 112:296–300 23. Vento M, Asensi M, Sastre J et al (2003) Oxidative stress in asphyxiated term infants resuscitated with 100% oxygen. J Pediatr 142:240–246 24. Davis PG, Tan A, O’Donnell CPF (2004) Resuscitation of newborn infants with 100% oxygen or air: a systematic review and meta-analysis. Lancet 364:1329–1333 25. Trevisanuto D, Doglioni N, Ferrarese P et al (2006) Neonatal resuscitation of extremely low birth weight infants: a survey of practice in Italy. Arch Dis Child Fetal Neonatal Ed 91:F123–F124 26. O’Donnell CPF. Davis PG, Morley CJ. Positive pressure ventilation at neonatal resusci- tation: review of equipment and international survey of practice. Acta Paediatr 93:583–588 27. Graham AN, Finer NN (2001) The use of continuous positive airway pressure and positive end-expiratory pressure in the delivery room. Pediatr Res 49:400A 28. Lindner W, Vossbeck S, Hummler H et al (1999) Delivery room management of extremely low birth weight infants: spontaneous breathing or intubation? Pediatrics 103:961–967 Resuscitation of the newborn 383 29. Van Marter LJ, Allred EN, Pagano M (2000) Do clinical markers of barotrauma and oxygen toxicity explain interhospital variations in chronic lung disease? Pediatrics 105:1194–1201 30. DreyfussD, SaumonG (1998)Ventilator-inducedlung injury.Lessons from experimen- tal studies. Am J Respir Crit Care Med 157:294–323 31. ClarkRH (1999) Supportof gas exchange indelivery roomand beyond:how dowe avoid hurting the baby we seek to save? Clin Perinatol 26:669–681 32. Trevisanuto D, Doglioni N, Micaglio M et al (2006) Neonatal resuscitation in Italy: an ethical perspective. Arch Dis Child Fetal Neonatal Ed (in press) 33. Peerzada JM, Schollin J, Hakansson S (2006) Delivery room decision-making for extremely preterm infants in Sweden. Pediatrics 117:1988–1995 384 D. Trevisanuto, N. Doglioni, F. Mario Regional anaesthesia in neonates M. ASTUTO,D.SAPIENZA,G.RIZZO The last decade has seen many advances in the management of pain in neonates, which are based upon an increased understanding of the neurophysiology of pain, combined with the development of clinical pain services, analgesic delivery devices and monitoring protocols. The nervous system of neonates is characterised by the absence of full myeli- nation and by poorly myelinated thalamocortical radiations. These elements must be considered as a reflection of immaturity but not as an indication of lack of function. The immaturity of the nociceptive system implies that young patients cannot localise pain as accurately as adults, and the corresponding perception of nociceptive sensation may be more widespread. The differences in subclasses of opioid receptors in neonates may contribute to a reduced ability to modulate nociceptive transmission. Painful experiences in very-low-weight infants may result in significantly higher somatisationscores.This increased understanding of paintransmissionand long-term pain consequences [1] underlines the need for a wide spectrum of strategies to achieve optimal patient pain relief. Regional anaesthesia is commonly used as an adjunct to general anaesthesia or, most commonly, as a means ofproviding postoperative analgesia. Peripheral (both continuous or single shot) and central blocks (epidural or spinal) and the use of new low-toxicity local anaesthetics, sometimes combined with nonopioid addi- tives, are current strategies of multimodal analgesia in neonates. When these proce- dures are applied to perform blocks it is essential to take account of the anatomical and physiological differences existing between neonates and children (Table 1). Table 1. Anatomical and physiological considerations in neonates and children Neonates Children 1 year Dural sac S-4 S2-S3 Spinal cord L-3 L1 Intercristal space L5–S1 L5 Lumbar lordosis Absent Present (acquired upright position) CSF 4 ml/kg (50% 4 ml/kg in spinal canal) Plasmatic level albumin/a-1 Very low Low glycoproteins Chapter 35 Peripheral nerve blocks Standard peripheral blocks, such as paraumbilical, axillary, intercostal, inguinal, penile and femoral blocks and those of the fascia iliaca compartment, are the mainstay of analgesic management for neonatal surgery. Peripheral nerve blocks may avoid the risks inherent in a central blockade and also its side-effects. Other advantages are: higher safety, less nausea/vomiting, less urinary retention, good postoperative analgesia that is long lasting, and the option of performing it even in anticoagulated or febrile patients. However, peripheral nerve blocks require multiple injections and larger vo- lumes of anaesthetic solution and have a longer onset time. Moreover, their limited effects in cavity surgery (thoracotomy/laparotomy) and their relatively short du- ration of action mean that they are less well suited to more major surgery. A ‘single-shot peripheral block’ means a single injection of a local anaesthetic. This technique is now widely used in infants, but can provide analgesia for only a few hours. Another drawback of these blocks is the relatively high failure rate. For example, although inguinal hernia repair is one of the most common surgical procedures performed in neonates and premature infants, the precise anatomical positions of both the ilioinguinal and the iliohypogastric nerves are still not identi- fied in this age group, and the relatively high failure rate of 10–25%, even when the technique is applied by experienced practitioners, could be due to a lack of specific spatial knowledge of the anatomy of these nerves in infants and neonates [2]. Direct ultrasonographic visualisation of the inguinal and iliohypogastric nerves might improve the quality of the block and reduce the risk of complications. The using of real-time imaging makes it possible to detect the precise location of the needle tip between the ilioinguinal and iliohypogastric nerves and to observe the spread of the local anaesthetic around both nerves. This allows the use of significan- tly smaller amounts of local anaesthetics while clinically effective blocks are still achieved. This is particularly relevant for neonates,who are at risk of local anaesthe- tic toxicity and higher free plasma concentrationsoflocal anaesthetic agents in view oftheirlowerplasmaconcentrationofthebindingproteinalpha-1 acidglycoprotein. The results of a recent study are encouraging and demonstrate a further application of the use of ultrasonography in paediatric regional anaesthesia [3]; it is important, however, to underline that ultrasound imaging in neonates should be considered an important and ongoing part of training in regional paediatric anaesthesia, as it is a way of demonstrating the relevant anatomical differences of this age group and many of the structures that regional anaesthetists seek to avoid are clearly shown: the pleura, arteries and veins. It is for this reason that the availability of ultrasound may lead to changes in regional neonatal anaesthetic practice. A ‘continuous peripheral nerve block (CPNB)’ means a continuous infusion of local anaesthetic/s. CPNBs are even safer than central ones and are very effective for long-term pain control. Many published studies demonstrate the efficacy and safety of analgesia via a peripheral catheter; no complications or side-effects linked to long-term infusions 386 M. Astuto, D. Sapienza, G. Rizzo have been described, and few accidental removals and little drug leakage have been described. CPNBs are at least as efficient as epidural analgesia, but produce fewer side-effects [4]. The use of ropivacaine and levobup ivacaine for CPNBs is particularly interesting in neonates, b ecause of the l ower cardiac and central nervous system ( CNS) toxic ity and differential sensory/motor blockade duration with these agents [5]. Ropivacaine is the drug of choice; it has the potential to produce a differential neural blockade with less pronounced motor block and induces less myotoxicity than bupivacaine [6]. There has so far been a lack of specific equipment for performance of such techniques in neonates, and practitioners have just used radial artery catheterisa- tion sets, epidural kits, and central venous catheter sets. A specially designed set for paediatric CPNB has recently been developed. It is composed of a 20-G bevelled (15°) conducting needle 33 or 55 mm long sheathed in a plastic cannula and a 22-G, 400-mm-long catheter with a wire. Data in the literature suggest that the starting bolus dose administered before a continuous infusion depends on the objective; 0.4–0.6 ml/kg of a low concentra- tion (e.g. 0.2% ropivacaine) is generally used for intraoperative pain control and for postoperative analgesia. Lidocaine 1.5% can be added to a bolus of 0.2% ropivacaine. A continuous infusion is then administered using 0.125–0.25% bupi- vacaine or 0.2% ropivacaine at 0.1–0.3 ml kg –1 h –1 , which is equivalent to 0.2–0.4 mg kg –1 h –1 . A 25–30% reduction in local anaesthetic is recommended for infants months [7]. In a recent study, Ivani et al. [8] demonstrated better postoperative analgesia achieved when 2 mg/kg clonidine was added to ropivacaine for an ilioingui- nal–iliohypogastric nerve block, but this observation was not supported by the results of the study published by Kaabachi et al. [9], which in fact failed to demonstrate a better postoperative analgesia following the addition of 1 mg/kg clonidine to 0.25% bupivacaine for ilioinguinal–iliohypogastric nerve blocks. These different effects ofasmalldoseof clonidine on the efficacy ofnerveblocks may be explained by the differences in the type of nerve block, mixture injected and technique used, which probably influence the rate of absorption of the anaesthetic solutions injected. Central blocks Epidural Epidural analgesia in combination with light general anaesthesia is a useful alter- native for neonates undergoing major surgery, avoiding the adverse effects related to systemic administration of opioids and other agents. Apart from providing good intraoperative and postoperative analgesia, epiduralblockade has beneficial effects on the humoral, metabolic, and haemodynamic responses to surgery and may improve postoperative respiratory performance. Regional anaesthesia in neonates 387 In experienced hands, the complicationrateof epidural analgesia islow.Serious complications have been described in small infants, including paraplegia and death. In most cases direct trauma is reported, and it seems probable that it is a result of difficulty in performing the epidural. Many authors share the opinion that only anaesthesiologists who are experienced in the technique should perform epidural anaesthesia in small infants and neonates. Caudal epidural anaesthesia remains the most frequently performed regional anaesthetic technique in infants and children. This is a popular single-shot tech- nique characterised by a high level of efficacy and safety. Of all central blocks, this is the one that has the lowest incidence of complications (0.7/1000 cases) [10]. In neonates and infants, the straighter column and less dense packing of the extradural space by fatand fibrous tissue allows catheters to be placed via the sacral hiatus, then threaded through to the thoracic region. This provides segmental thoracic analgesia, yet avoids the hazards associated with direct needling of the thoracic extradural space. Catheters may also be passed to low lumbar levels for lumbar blocks, so that the larger doses of local anaesthetic needed when the injection is performed at the sacral hiatus are avoided. Correct cannula placement and catheter level should be checked to avoid high blocks and respiratory compromise or low blocks and inadequate analgesia. A number of techniques have been described for the confirmation of correct or intravascular placement, but the novel use of ultrasound to visualise the epidural catheter has a particularly high potential for impr oving safety and providing better quality analgesia [11, 12]. Toxicity of local anaesthetics affects the heart and the brain and is commonly produced as a result of inadvertent intravascular administration or administration of an excessive bolus dose. Owing to the lower level of the plasma protein a1-acid glycoprotein, albumin, and lower bicarbonate reserves, neonates have a high risk of bupivacaine toxicities, such as cardiac dysrhythmia or respiratory arrest, which are more likely in neo- nates and infants than convulsions [13]. This can be avoided by using bolus doses and infusion rates that are within the recommended guidelines and by taking account of the pharmacokinetics of local anaesthetics in neonates. Pharmac okinetic studies of several local anaesthetics have been performed in neonates and have produced important information on the safe use of local anaesthetics in neonates. Pharmacokinetic studies on bupivacaine showed a reduction of clearance in neo- nates reaching mature values by 4–6 months of age. An infusion rate of 0.2 mg kg –1 h –1 provokes a continuous increase in the plasma concentration, which rises to the threshold for toxicity in about 72 h. Therefore, bupivacaine infusion rates of 0.4 mg kg –1 h –1 are safe in infants aged more than 6 months, but infusion rates in neonates should be no faster than 0.2 mg kg –1 h –1 [14]. Ropivacaine has a number of advantages that could be considered important in neonates. These include l ower cardiotoxicity tha n a re a ssociated with eq ual c oncen- trations ofracemicbupivacaine andahigher threshold for CNStoxicity oft he unbound concentration. The greater degree of block in nerve fibres of pain transmission than of motor function for a given concentration [15] would be of further benefit. 388 M. Astuto, D. Sapienza, G. Rizzo [...]... internationally, and the model discriminates accurately between death and survival PIM was developed from data collected between 199 4 and 199 6 in seven PICUs in Australia and one in the United Kingdom [6] PIM2 was developed from data collected between 199 7 and 199 9 in 13 ICUs in Australia, New Zealand and the United Kingdom [7] PIM and PIM2 use data collected at the time of intensive care admission or... 31:66 8-6 71 46 Kokki H, Hendolin H, Vainio J et al ( 199 2) Operationen im Vorschulalter: Vergleich von Spinalanasthesie und Allgemeinanasthesie Anaesthetist 41:76 5-7 68 47 Kokki H, Hendolin H ( 199 5) Comparison of spinal anaesthesia with epidural anaesthesia in paediatric surgery Acta Anaesthesiol Scand 39: 89 6 -9 00 48 Melman E, Penuelas J, Marrufo J ( 197 5) Regional anesthesia in children Anesth Analg 54:38 7-3 90 ... Anesth Analg 54:38 7-3 90 49 Parkinson SK, Little WL, Malley RA et al ( 199 0) Use of hyperbaric bupivacaine with epinephrine for spinal anesthesia in infants Reg Anesth 15:8 6-8 8 50 Rice LJ, DeMars PD, Whalen TV et al ( 199 4) Duration of spinal anesthesia in infants less than one year of age Reg Anesth 19: 32 5-3 29 51 Aronsson DD, Gemery JM, Abajian JC ( 199 6) Spinal anesthesia for spine and lower extremity... 10: 5-1 6 34 Shenkman Z, Hoppenstein D, Litmanowitz I et al (2002) Spinal anesthesia in 62 premature, former-premature or young infants-technical aspects and pitfalls Can J Anaesth 49: 26 2-2 69 35 Mahe V, Ecoffey C ( 198 8) Spinal anesthesia with isobaric bupivacaine in infants Anesthesiology 68:60 1-6 03 36 Kokki H, Touvinen K, Hendolin H ( 199 8) Spinal anaesthesia for paediatric day-case surgery: a double-blind,... first 24 h after intensive care admission Age, operative status and the PRISM score are used to predict the risk of death PRISM III was derived from data collected in units in the United States in 199 3 and 199 4 [10] With this revision, the method of assigning points for abnormalities in physiology was refined and variables that adjust for treatment given before intensive care admission and for five specific... prolongs analgesia from caudal S(+)-ketamine in children Anesth Analg 94 :116 9- 1 172 21 Ooi R, Pattison J, Feldman SA ( 199 1) The effects of intravenous clonidine on ventilation Anaesthesia 46:63 2-6 33 394 M Astuto, D Sapienza, G Rizzo 22 O’Halloran KD, Herman JK, Bisgard GE (2000) Ventilatory effects of alpha2-adrenoceptor blockade in awake goats Respir Physiol 126:2 9- 4 1 23 De Negri P, Ivani G, Visconti... with ultrasound in children Paediatr Anaesth 13:68 1-6 84 12 Roberts SA, Guruswamy V, Galvez I (2005) Caudal injectate can be reliably imaged using portable ultrasound – a preliminary study Paediatr Anaesth 15 :94 8 -9 52 13 Bosenberg A ( 199 8) Epidural analgesia for major neonatal surgery Paediatr Anaesth 8:47 9- 4 83 14 Larsson BA, Lonnqvist PA, Olsson GL ( 199 7) Plasma concentrations of bupivacaine in neonates... anesthesia in high-risk infants J Pediatr Surg 27:102 2-1 025 43 Blaise GA, Roy WL ( 198 6) Spinal anaesthesia for minor paediatric surgery Can Anaesth Soc J 33:22 7-2 30 Regional anaesthesia in neonates 395 44 Tobias JD, Flannagan J, Brock J et al ( 199 3) Neonatal regional anesthesia: alternative to general anesthesia for urologic surgery Urology 41:36 2-3 65 45 Tobias JD, Flannagan J ( 199 2) Regional anesthesia... neonates and infants Paediatr Anaesth 15:73 9- 7 49 18 Chalkiadis GA, Anderson BJ, Tay M et al (2005) Pharmacokinetics of levobupivacaine after caudal epidural administration in infants less than 3 months of age Br J Anaesth 95 :52 4-5 29 19 Fellmann C, Gerber AC, Weiss M (2002) Apnoea in a former preterm infant after caudal bupivacaine with clonidine for inguinal herniorrhaphy Paediatr Anaesth 12:63 7-6 40 20... inguinal surgery in children Paediatr Anaesth 12:68 0-6 84 9 Kaabachi O, Zerelli Z, Methamem M (2005) Clonidine administered as adjuvant for bupivacaine in ilioinguinal-iliohypogastric nerve block does not prolong postoperative analgesia Paediatr Anaesth 15:58 6-5 90 10 Lloyd-Thomas AR ( 199 9) Modern concepts of paediatric analgesia Pharmacol Ther 83: 1-2 0 11 Chawathe MS, Jones RM, Gildersleve CD et al (2003) . Pediatrics 105:1 194 –1201 30. DreyfussD, SaumonG ( 199 8)Ventilator-inducedlung injury.Lessons from experimen- tal studies. Am J Respir Crit Care Med 157: 294 –323 31. ClarkRH ( 199 9) Supportof gas. epidural anaesthe- sia in paediatric surgery. Acta Anaesthesiol Scand 39: 89 6 -9 00 48. Melman E, Penuelas J, Marrufo J ( 197 5) Regional anesthesia in children. Anesth Analg 54:38 7-3 90 49. Parkinson. Anesth 19: 32 5-3 29 51. Aronsson DD, Gemery JM, Abajian JC ( 199 6) Spinal anesthesia for spine and lower extremity surgery in infants. J Pediatr Orthop 16:25 9- 2 63 52. Tobias JD, Mencio GA ( 199 8) Regional