Analgesia and anesthesia in neonates

Narcotic Utilization After Cleft Lip Repair: Does Local Anesthetic Choice Matter?

To analyze whether the choice of intraoperative local anesthetic for cleft lip repair is associated with the amount of perioperative narcotic utilization.

Retrospective cohort study.

Hospitals participating in the Pediatric Health Information System.

Primary cleft lip repairs performed in the United States from 2010 to 2020.

Local anesthesia injected-treatment with lidocaine alone, bupivacaine alone, or treatment with both agents.

Perioperative narcotic administration.

During the study interval, 8954 patients underwent primary cleft lip repair. Narcotic utilization for unilateral (P < .001) and bilateral (P = .004) cleft lip repair has decreased over the last 5 years. Overall, 21.8% (n = 1950) of infants were administered perioperative narcotics for cleft lip repair, such that 14.3% (n = 1282) required narcotics on POD 0, and 7.2% (n = 647) required narcotics on POD 1.In this study, 36.5% (n = 3269) patients received lidocaine, 22.0% (n = 1966) patients received bupivacaine, and 19.7% (n = 1762) patients received both local anesthetics. Administration of any perioperative narcotic was significantly lower in patients receiving both lidocaine and bupivacaine than those receiving only lidocaine (P = .001, 17.5% vs 21.7%) or only bupivacaine (P < .001, 17.5% vs 22.9%). Narcotic utilization on the day of surgery was significantly lower in patients receiving both lidocaine and bupivacaine than those receiving only lidocaine (P < .001, 11.5% vs 15.1%) or only bupivacaine (P = .004, 11.5% vs 14.6%). Narcotic utilization on the first postoperative day was significantly lower in patients receiving both lidocaine and bupivacaine than those receiving only bupivacaine (P = .009, 5.9% vs 8.1%).

CONCLUSIONS

In children undergoing cleft lip repair, local anesthetic combination of lidocaine and bupivacaine is associated with decreased perioperative narcotic use compared to lidocaine or bupivacaine alone.

The fetal pain paradox

Controversy exists as to when conscious pain perception in the fetus may begin. According to the hypothesis of cortical necessity, thalamocortical connections, which do not form until after 24-28 weeks gestation, are necessary for conscious pain perception. However, anesthesiologists and neonatologists treat age-matched neonates as both conscious and pain-capable due to observable and measurable behavioral, hormonal, and physiologic indicators of pain. In preterm infants, these multimodal indicators of pain are uncontroversial, and their presence, despite occurring prior to functional thalamocortical connections, has guided the use of analgesics in neonatology and fetal surgery for decades. However, some medical groups state that below 24 weeks gestation, there is no pain capacity. Thus, a paradox exists in the disparate acknowledgment of pain capability in overlapping patient populations. Brain networks vary by age. During the first and second trimesters, the cortical subplate, a unique structure that is present only during fetal and early neonatal development, forms the first cortical network. In the third trimester, the cortical plate assumes this function. According to the subplate modulation hypothesis, a network of connections to the subplate and subcortical structures is sufficient to facilitate conscious pain perception in the fetus and the preterm neonate prior to 24 weeks gestation. Therefore, similar to other fetal and neonatal systems that have a transitional phase (i.e., circulatory system), there is now strong evidence for transitional developmental phases of fetal and neonatal pain circuitry.

An interview with Dr. Anne Marie Lynn, a pioneering woman in medicine

Dr. Anne Marie Lynn (1949-present), Professor Emeritus of Anesthesiology, Pain Medicine, and Pediatrics at the University of Washington, Seattle, was one of the most influential women in pediatric anesthesiology of her generation. Dr. Lynn embodies the spirit of discovery and advancement that have created the practice of pediatric anesthesiology as we know it today. A pioneer in pain medicine pharmacology, particularly morphine and ketorolac, her research transformed pediatric anesthesia, pediatric pain medicine, and pediatric intensive care medicine. Through her journal articles, book chapters, national and international lectures, mentoring of residents, fellows, and faculty, and leadership in the Society for Pediatric Anesthesia, she inspired a generation of women and men physicians by demonstrating that gender should not be a barrier to undertaking roles once only held only by men. In 2017, for her many contributions, she was awarded the Society for Pediatric Anesthesia's Myron Yaster lifetime achievement award.

Opioid Prescribing Practices in Cleft Lip and Cleft Palate Reconstruction

INTRODUCTION

Currently, there is no consensus regarding the role of opioids in the management of perioperative pain in children undergoing cleft lip/palate repair.

METHOD

The present study evaluated opioid prescribing patterns of surgeon members within the American Cleft Palate-Craniofacial Association surgeons utilizing an anonymous survey.

RESULTS

Respondents performing cleft lip repair typically operate on patients 3 to 6 months of age (86%), admit patients postoperatively (82%), and discharge them on the first postoperative day (72%). Comparatively, respondents performed palatoplasty between the ages of 10 and 12 months (62%), almost always admit the patients (99%), and typically discharge on the first postoperative day (78%). Narcotics were more frequently prescribed after palatoplasty than after cleft lip repair, both for inpatients (66%; 49%) and at discharge (38%; 22%). Oxycodone was the most prescribed narcotic (39.1%; 41.4%), typically for a duration of 1 to 3 days (81.5%; 81.2%). All surgeons who reported changing their narcotic regimen (34.4% dose, 32.8% duration) after cleft lip repair, decreased both parameters from earlier to later in their career. Similarly, surgeons who changed the dose (32.2%) and duration (42.5%) of narcotics after palatoplasty, mostly decreased both parameters (96%). Additionally, physicians with >15 years of practice were less likely to prescribe opioids in comparison with colleagues with ≤15 years of experience. Ninety-two percent of respondents endorsed prescribing nonopioid analgesics after prescribing cleft surgery, most commonly acetaminophen (85.7%; 85.4%).

CONCLUSION

Cleft surgeons typically prescribe opioids to inpatients and rarely upon discharge. Changes to opioid-prescribing patterns typically involved a decreased dose and duration.

Discovering Pain in Newborn Infants

Randomised Trial of Fentanyl Anesthesia in Preterm Babies Undergoing Surgery: Effects on the Stress Response. By Anand KJ, Sippell WG, and Aynsley-Green A. Lancet 1987; 1:243-8. Reprinted with permission.In a randomised controlled trial, preterm babies undergoing ligation of a patent ductus arteriosus were given nitrous oxide and D-tubocurarine, with (n = 8) or without (n = 8) the addition of fentanyl (10 μg/kg intravenously) to the anesthetic regimen. Major hormonal responses to surgery, as indicated by changes in plasma adrenaline, noradrenaline, glucagon, aldosterone, corticosterone, 11-deoxycorticosterone, and 11-deoxycortisol levels, in the insulin/glucagon molar ratio, and in blood glucose, lactate, and pyruvate concentrations were significantly greater in the nonfentanyl than in the fentanyl group. The urinary 3-methylhistidine/creatinine ratios were significantly greater in the nonfentanyl group on the second and third postoperative days. Compared with the fentanyl group, the nonfentanyl group had circulatory and metabolic complications postoperatively. The findings indicate that preterm babies mount a substantial stress response to surgery under anesthesia with nitrous oxide and curare and that prevention of this response by fentanyl anesthesia may be associated with an improved postoperative outcome.

Postoperative analgesia for cleft lip and palate repair in children

Acute pain such as postoperative pain during infancy was ignored approximately three decades ago due to biases and misconceptions regarding the maturity of the infant's developing nervous system, their inability to verbally report pain, and their perceived inability to remember pain. More recently, these misconceptions are rarely acknowledged due to enhanced understanding of the developmental neurobiology of infant pain pathways and supraspinal processing. Cleft lip and palate is one of the most common congenital abnormalities requiring surgical treatment in children and is associated with intense postoperative pain. The pain management gets further complicated due to association with postsurgical difficult airway and other congenital anomalies. Orofacial blocks like infraorbital, external nasal, greater/lesser palatine, and nasopalatine nerve blocks have been successively used either alone or in combinations to reduce the postoperative pain. Since in pediatric population, regional anesthesia is essentially performed under general anesthesia, association of these two techniques has dramatically cut down the risks of both procedures particularly those associated with the use of opioids and nonsteroidal anti-inflammatory drugs. Definitive guidelines for postoperative pain management in these patients have not yet been developed. Incorporation of multimodal approach as an institutional protocol can help minimize the confusion around this topic.

Bilateral Infraorbital Nerve Block Versus Intravenous Pentazocine: A Comparative Study on Post-operative Pain Relief Following Cleft Lip Surgery

BACKGROUND AND OBJECTIVES

Infra orbital nerve block is utilized for postoperative pain control in children undergoing cleft lip repair. This study was conducted to compare the effectiveness, advantages and disadvantages of infra orbital nerve block and opioids for postoperative pain relief following cheiloplasty.

MATERIALS AND METHODS

Sixty paediatric patients aged 3 months - 13 years undergoing cheiloplasty were selected by simple random sampling and were divided into two groups. All the children received standardized premedication with midazolam, were operated upon under general anaesthesia and the block was performed at the end of surgery before reversal. Group B patients were administered bilateral infra orbital nerve block with 0.25% Bupivacaine (upto 2 mg/kg). Group O patients received Pentazocine 0.5 mg / kg IV. Postoperatively, the heart rate and respiratory rates were recorded every 15 minutes for the first 60 minutes, half hourly till 4 hours and then at 12 and 24 hours. Behavioural assessment for pain / discomfort was done at intervals of ½, 1, 2, 3, 4, 12 and 24 hours. Need for supplementary analgesics and duration between the administration of block/opioid and the first dose of supplementary analgesics were noted. Side effects such as nausea and vomiting, pruritus, respiratory depression and bradycardia during each of these periods were noted.

RESULTS

Both the groups were comparable for age, sex, weight and operative time with no statistical difference. The mean duration of analgesia for infra orbital nerve block was 357.5 minutes i.e. 5 hours 58 minutes and that for opioid was 231 minutes i.e. 3 hours 51 minutes which was significantly lower than the hours of analgesia provided by the block. Further, at the 4th hour, 76.6% of the patients in Group O required supplementary analgesics, in contrast to only 16.6% in Group B. The incidence of nausea and vomiting and pruritus was also higher in Group O.

CONCLUSION

The results indicate that bilateral infra orbital nerve block provides effective analgesia in the postoperative period, lasting for 6 hours in comparison to 3½ - 4 hours following the administration of intravenous Pentazocine, with no major untoward effects.

Analgesic effects of skin-to-skin contact and breastfeeding in procedural pain in healthy term neonates

OBJECTIVES

The effectiveness of skin-to-skin contact to decrease pain from heel-lancing in healthy term neonates and whether breastfeeding in addition to skin-to-skin contact provided a more effective analgesia than skin-to-skin contact alone were investigated.

METHODS

A randomised, controlled trial was conducted in 107 neonates undergoing heel-lance. Infants were randomly assigned to three groups: (i) being breastfed with skin-to-skin contact (group 1, n=35), (ii) being held in their mother's arms with skin-to-skin contact but no breastfeeding (group 2, n=36), or (iii) lying on the table before, during and after painful stimulus (group 3, n=36). Physiological responses to pain were measured by heart rate and oxygen saturation changes and behavioural responses were measured by duration of crying and grimacing.

RESULTS

Infants had a mean (SD) birthweight of 3355 (270) g and gestational age of 39.5 (0.6) weeks; at the time of the procedure, mean (SD) postnatal age was 33.1 (5) hours. There was no significant difference between the groups in clinical characteristics and time spent squeezing the heel. Heart rate, oxygen saturation changes and length of crying were significantly reduced in groups 1 and 2 compared with group 3 (p<0.001). No difference was found between group 1 and group 2. Grimacing was less in group 2 than in group 3 (p<0.001).

CONCLUSIONS

In healthy term neonates, skin-to-skin contact with the mother and breastfeeding with skin-to-skin contact reduce both physiological and behavioural pain response. Breastfeeding in the 1st 2 postnatal days with skin-to-skin contact did not increase the analgesic effect of skin-to-skin contact alone.

Analgesia in preterm newborns: the comparative effects of sucrose and glucose

The aim of this study was to evaluate the effectiveness of different oral carbohydrate solutions for alleviation of pain in healthy preterm babies. Thirty-one preterm infants who were having blood drawn by heel prick were given 2 ml of solution A (20% sucrose), solution B (20% glucose) or solution C (placebo, sterile water) into the mouth, 2 min before lancing. Behavioural responses to this painful stimulus were measured by duration of crying and facial expressions (Neonatal Facial Coding System, NFCS) and physiological responses were measured by heart rate (HR), respiratory rate (RR), and oxygen saturation changes (SaO(2)). Infants had a mean birth weight (+/-SD) of 1,401 g (406), gestational age of 30.5 weeks (2.7); at the time of the procedure the postmenstrual age was 32.3 weeks (1.5). There was no significant difference in the time spent squeezing the heel between the three groups (P = 0.669). After the heel prick of both the sucrose and glucose groups the duration of first cry and total crying time was significantly reduced (P = 0.005 and P = 0.007). When the babies received placebo they showed a significantly higher NFCS score at 4 and 5 min after the heel prick (P = 0.009 and 0.046 respectively). Following painful stimulus HR increased significantly in the first 3 min compared with baseline, and at the first minute the mean of the HR was found to be significantly higher in the placebo group than in the sucrose and glucose groups (P = 0.007). We concluded that both sucrose and glucose administered orally before a heel prick reduce the pain response in preterm infants.

Pediatric Anesthesia Historical Perspective

This article examines how anesthesia evolved to serve the needs of children. Discussion includes milestones in technologic advancement related to pediatric anesthetic care and how collaboration among pediatric surgeons, neonatologists, and pediatric anesthesiologists has helped our specialty to progress. Conversely, the significant contributions of pediatric anesthesiology to pediatric critical care medicine, pain management, and pediatric public health care are also presented.

Our youngest patients' pain--from disbelief to belief?

Though human pain has existed since the dawn of time, formal medical pain relief in the form of anesthesia and analgesia has been available only since the mid-nineteenth century. Even after these measures became available, they were used very selectively for the first 100 years of their existence. The youngest patients, especially, were denied pain relief, probably because they could not complain about their pain as articulately and as effectively as adult patients could. A desperate need existed for health care professionals to recognize and appreciate the fact that their youngest patients could suffer immensely and to adequately address the issue. This article reviews the evolution of knowledge and attitudes regarding young patients' pain and addresses why and how this process occurred. The evolution of knowledge was traced by reviewing the literature found in MEDLINE, CINAHL, and LEXIS-NEXIS searches and through hand searches of articles that were frequently cited. Physiologic, pharmacologic, ethical, and psychologic aspects of young patients' pain are addressed. A unique phenomenon arose from the data reviewed. The process of belief and changes in practice were encouraged not only by advances in science, but also by consumer demand. Advances in the past decade in the management of young patients' pain were profound, but are still not complete. Understanding the evolution surrounding pain recognition in young patients provides a stepping stone that can facilitate further improvements in the management of pain in young patients.

Methodological considerations for the use of heart rate variability as a measure of pain reactivity in vulnerable infants

Measures of HR and HRV offer multiple indices of reactivity to painful events. These measures are particularly helpful in preterm and ill infants where distress signals are often nonspecific and ambiguous. HR is easy to acquire, and a variety of widely used techniques are available for processing it. In general, the neuroanatomic and neurophysiologic bases for pain perception are in place even in the most preterm infant and produce patterns of HR and HRV responses that are similar across multiple settings. Developmental and experiential factors related to preterm birth, however, may affect these HR responses. Furthermore, evaluation of ill infants in an NICU setting adds multiple contextual factors that potentially influence HR and HRV and alter their specificity as measures of pain. In some cases, it may appear that pain reactivity is reduced when, in fact, HR reactivity is only an expression of the biologic capacity to produce a response, not the presence of a response itself. The nature of the setting and the infant's health, developmental stage, and behavioral state all contribute to potentially altering HR responses to painful events in this setting. Thus, the methodology used and its application must be flexible. A variety of HRV analysis techniques may be needed to identify a variety of response patterns and mechanisms that influence pain reactivity. Furthermore, careful selection of HR epochs for stationarity, an understanding of the potential discordance between biologic and behavioral measures, the effects of medication, and an accounting for developmental differences that occur during a typical NICU course are all critical factors for investigators to be aware of. Understanding cardiovascular reactivity as a measure of response to painful events in vulnerable infants requires ongoing work.

Morphine pharmacokinetics and pain assessment in premature newborns

OBJECTIVES

To determine morphine pharmacokinetics in premature neonates varying in postconceptional age (PCA) and evaluate behavioral pain response in relationship to serum morphine concentrations.

METHODS

Premature neonates (n = 48), stratified by weeks of PCA (group 1 = 24-27 weeks, group 2 = 28-31 weeks, group 3 = 32-35 weeks, and group 4 = 36-39 weeks) received morphine infusions. Blood samples were drawn at 48, 60, and 72 hours and at discontinuation of morphine, followed by 3 samples obtained during the next 24 hours. Newborns were videotaped during heel lances and restful states, with morphine at steady-state concentrations and without morphine. Pain was assessed by using the Neonatal Facial Coding System (NFCS). Statistical analysis included regression between NFCS score changes from baseline to painful procedure with and without morphine.

RESULTS

Morphine clearance for groups 1, 2, 3, and 4 was calculated as 2.27 +/- 1.07, 3.21 +/- 1.57, 4.51 +/- 1.97, and 7.80 +/- 2.67 mL/kg/min, respectively, and correlated with PCA (r = 0.63, P <.001). Pain measured by facial expression was diminished; however, it did not correlate with morphine concentrations.

CONCLUSION

Morphine clearance in premature neonates is less than reported, increasing with PCA. Facial activity discloses morphine analgesia; however, it is unrelated to morphine concentrations.

Long-term alterations in opiate antinociception resulting from infant fentanyl tolerance and dependence

Postnatal day-14 (P14) infant rats remained naive or were implanted with osmotic minipumps infusing saline or fentanyl (50 microg kg(-1) h(-1)). Fentanyl was administered 72 h later for measurement of antinociception in the tail-flick test. The potency of fentanyl was 3.0-fold lower in fentanyl-infused compared to saline-infused P17 rats. Fentanyl-infused P17 rats injected with naloxone underwent withdrawal characterized by increases in spontaneous activity, wall climbing, diarrhea, abdominal stretching, forepaw treading/tremors, wet-dog shakes, jumping, ptosis, rhinorrhea and hypothermia. Other naive, saline-infused and fentanyl-infused P17 rats not challenged with fentanyl or naloxone were housed until maturing into P42 juveniles. Fentanyl's potency was equal among each treatment group. However, morphine's potency was reduced in juveniles tolerant to fentanyl as infants. Morphine was also less potent in P90 adults tolerant to fentanyl as infants. Thus, chronic opiate exposure during infancy may affect the developing central nervous system, and desensitize animals and humans to opiate analgesia throughout life.

Characterization of neonatal rat morphine tolerance and dependence

The administration of morphine and fentanyl by continuous intravenous infusion has been shown to produce analgesic tolerance and physical dependence in human neonates. In animals, daily repeated morphine bolus injections is a common method of inducing neonatal rat tolerance and dependence. Yet this method differs from the intravenous route reported to affect human neonates. Alzet osmotic minipumps were implanted in postnatal day 14 rats to provide a continuous morphine infusion more closely mimicking the clinical picture. Rats remained naive or were infused with saline or morphine (0.7 mg/kg/h) for 72 h. Morphine's antinociceptive potency was similar between naive and saline-infused animals, while morphine-infused animals were tolerant. Gender did not contribute to the degree of tolerance observed. Naloxone precipitated withdrawal in the morphine pump-implanted rats was similar to that reported by others. Thus, minipumps provide a useful model for assessing the tolerance and dependence liability of different opioids.

Differential ontogenesis of thermal and mechanical antinociception induced by morphine and beta-endorphin

The antinociceptive effects induced by beta-endorphin and morphine given supraspinally have been previously demonstrated to be mediated by the activation of different neural mechanisms. The present experiments were to examine the effects of intraventricular administration of beta-endorphin and morphine in mechanical paw-withdrawal and thermal tail-flick nociceptive tests in rats of 2-28 days of age. 2-4-day-old neonates were not responsive to i.c.v. injection of beta-endorphin or morphine for the inhibition of the tail-flick response. The thermal antinociceptive responses induced by beta-endorphin and morphine started to develop in 7-14-day-old rats and continued to increase at 21-28 days. The inhibition of the mechanical paw-withdrawal response to beta-endorphin was already present in 2-day-old rats and morphine in 4-day-old rats. The mechanical antinociception progressively increased and reached a plateau at 7 days of age for beta-endorphin and 28 days of age for morphine. beta-Endorphin was found to be more efficacious than morphine in producing mechanical antinociception. The results demonstrate that beta-endorphin- and morphine-induced antinociception to mechanical and thermal stimuli develops differently and are consistent with the hypothesis that two descending pain inhibitory systems activated by beta-endorphin and morphine are differentially developed.

A comparison of the antinociceptive effects of opioid agonists in neonatal and adult rats in phasic and tonic nociceptive tests

Changes in the attitudes about neonatal pain and pain management have recently resulted in increases in the administration of opioids to neonates. Little is known, however, about the relative potencies of the various opioid agonists employed, especially in comparison to adult responses. The first objective in the present study was to compare the antinociceptive potency of four clinically relevant opioids in neonatal and adult rats. The second objective was to compare and contrast these agents in two different types of nociceptive tests: tonic (formalin-induced inflammation) and phasic (tail flick and hot plate). Our results indicate that the opioid agonists morphine, meperidine, and fentanyl, and the mixed agonist buprenorphine were all effective antinociceptive agents in both neonates and adults in each of the three tests employed, and that the relative potencies of these agents appeared to be similar in neonates and adults. In general, the pups were more sensitive to the antinociceptive agents when tested in the phasic nociceptive tests, and the drugs were more potent in the tonic test than either of the phasic tests.

Sedative-analgesic agent administration in children: analysis of use and complications in the emergency department

The frequency of, indications for, and complications from non-acetaminophen sedative-analgesic agents (SAAs) administered to children less than 16 years of age in the emergency department (ED) were determined by a retrospective review. All 21,353 charts from a single university hospital ED over a 16-month period were included. Few children (N = 759; 3.5%) received SAAs. Of 919 total doses, 13% of children received a second and 4.5% received a third SAA. The group was 59% male. Most children were < or = 10 years of age. Sixty-two percent of SAAs were either sedatives or opioids. Sedatives given included chloral hydrate, diazepam, lorazepam, midazolam, and phenobarbital. Opioids given included morphine, codeine, and meperidine. Indications for SAAs included painful procedures, analgesia, radiographic imaging, and seizure activity. Complications (N = 51; 6.7%) included inadequate sedation, vomiting, and respiratory depression or oxygen desaturation. Respiratory depression or oxygen desaturation occurred only after intravenous administration of SAAs for seizures. In children, non-acetaminophen SAAs are used most commonly in younger patients requiring sedation for painful procedures or for radiologic imaging. Respiratory depression was observed only after intravenous administration of anticonvulsants.

Neonatal pain: a comprehensive survey of attitudes and practices

We surveyed 352 physicians board certified in neonatal-perinatal medicine on their attitudes and practices in the area of pain and pain management in neonates and infants. In contrast to earlier surveys of this type, almost all respondents indicated that even the youngest and most premature infants are able to perceive pain, and most reported that they always advocated anesthesia during the intraoperative period. The use of analgesic agents in the postoperative period, however, was more variable. Respondents who indicated that neonates perceived less pain than adults reported seeing fewer signs of pain and using less analgesia in the postoperative period. They were also more likely to believe that analgesics are too dangerous to use in neonates and that physiologic factors such as incomplete myelination of the pain pathways and neural/physical immaturity (factors now known not to play a role) contribute to diminished pain sensitivity. Conversely, respondents who indicated that neonates do not perceive less pain than adults, the majority of respondents, reported seeing more signs of pain and using more medication in the postoperative period. These physicians also believed that the physiologic stress associated with pain can be more dangerous than the analgesics. We conclude that attitudes and reported practices have changed in the area of neonatal pain and pain management. Furthermore, our data indicate that these attitudes significantly predict reported postoperative medicating practices.

Analgesic effects of intraventricular and intrathecal injection of morphine and ketocyclazocine in the infant rat

Little is known of the neural bases of analgesia in immature animals. This experiment examined the effects of intracerebroventricular (i.c.v.) and intrathecal (i.t.) administration of morphine or ketocyclazocine in tests of antinociception in rats aged 3 to 14 days of age. Analgesia tests were conducted using both thermal and mechanical (pressure) noxious stimuli applied to the forepaw, hindpaw or tail. In the 3-day-old morphine-injected i.c.v. produced analgesia in the forepaws when either the mechanical or thermal noxious stimulus was used. There was no effect when the hindpaw or tail was tested. At 10 days of age, when the mechanical stimulus was used, morphine was analgesic in tests on all three appendages but was only effective in the forepaw when the thermal stimulus was used. Morphine was fully effective in all tests with both stimuli at 14 days of age. Ketocyclazocine had no consistent effect when given i.c.v. When injected i.t., morphine produced analgesia in the forepaws in the thermal test at 4 days of age and in all appendages by 10 days. When the mechanical test was used, morphine was effective in all appendages at all ages tested. Ketocyclazocine was analgesic at all appendages for the mechanical stimulus at all ages but was only transiently effective in the thermal test. The results demonstrate differential development of analgesia mediated at different levels of the neural axis and are consistent with the development of descending inhibitory that may mediate analgesia induced by i.c.v. injections of morphine. Neural mechanisms that are involved in the analgesic effects of these drugs against the two types of stimuli are also developmentally distinct.

Perioperative pain management in children: a review

Pain in children from the neonate to the teenager has recently begun to achieve the attention it deserves in the medical literature. Practitioners have been slow to apply both old and new techniques in this patient population. This review focuses on the perioperative management of pain and its associated symptoms in pediatric patients.

Psychiatric symptoms of pediatric cancer pain

This study investigated the contribution of pain to psychiatric symptoms in 43 hospitalized children and adolescents referred for psychiatric evaluation in a pediatric cancer center during a 1-yr period. Procedures included determination of the primary reason for referral, child and parent diagnostic interviews assessing pain history and psychiatric symptoms, and recommendations for improved pain control or other types of intervention and followup. Across the four referral categories (for symptoms of depression, cognitive/perceptual disturbance, anxiety, or disruptive behavior), approximately 20% of all consultations resulted in a primary recommendation for improved pain control. The findings suggest that pediatric cancer pain may go untreated when its manifestations are psychiatric. Implications for staff education, consultation-liaison psychiatry, and psychiatric nosology are discussed.

Opioids and the developing organism: a comprehensive bibliography, 1984-1988

A comprehensive bibliography of the literature concerned with opioids and the developing organism for 1984-1988 is presented. Utilized with companion papers (Neurosci. Biobehav. Rev. 6:439-479; 1982; 8:387-403; 1984), these articles cover the clinical and laboratory references beginning in 1875. For the years 1984, 1985, 1986, 1987, and 1988, a total of 877 citations were recorded. A series of indexes accompanies the citations in order to make the literature more accessible. These indexes are divided into clinical and laboratory topics, and subdivided into such topics as the type of opioid explored and the general area of biological interest (e.g., physiology).

Management of pediatric pain with opioid analgesics

We have attempted to dispel many of the myths and misconceptions surrounding the use of narcotic analgesics in the treatment of childhood pain. Our hope is that an improved understanding and the application of effective, safe therapy will minimize the suffering of the child with acute or chronic pain.