A systematic review of the prevalence of chronic postsurgical pain in children.

Two prior reviews highlight the scarcity and conflicting nature of available data on chronic postsurgical pain in children, reporting a wide prevalence range of 3.2% to 64% (at ≥3 months). This updated systematic review aimed to consolidate information on the prevalence of pediatric chronic postsurgical pain. A thorough literature search of full English-text publications from April 2014 to August 2021 was conducted using Ovid MEDLINE, PubMed, and Cochrane Database of Systematic Reviews, with search terms: postoperative pain, child, preschool, pediatrics, adolescent, chronic pain. Seventeen relevant studies were identified. Most assessed chronicity once greater than 3 months duration postoperatively (82%), were predominantly prospective (71%) and conducted in inpatient settings (88%). The surgeries examined included orthopedic (scoliosis and limb), urological, laparotomy, inguinal, and cardiothoracic procedures, involving numbers ranging from 36 to 750, totaling 3137 participants/2792 completers. The studies had wide variations in median age at surgery (6 days to 16 years), the percentage of female participants (unspecified or 12.5% to 90%), and follow-up duration (2.5 months to 9 years). Various pain, functional, psychosocial, and health-related quality of life outcomes were documented. Chronic postsurgical pain prevalence varied widely from 2% to 100%. Despite increased data, challenges persist due to heterogeneity in definitions, patient demographics, mixed versus single surgical populations, diverse perioperative analgesic interventions, follow-up durations and reported outcomes. Interpretation is further complicated by limited information on impact, long-term analgesia and healthcare utilization, and relatively small sample sizes, hindering the assessment of reported associations. In some cases, preoperative pain and deformity may not have been addressed by surgery and persisting pain postoperatively may then be inappropriately termed chronic postsurgical pain. Larger-scale, procedure-specific data to better assess current prevalence, impact, and whether modifiable factors link to negative long-term outcomes, would be more useful and allow targeted perioperative interventions for at-risk pediatric surgical patients.

Sensory Modulation: An Important Piece of the Disability Puzzle for Adolescents With Persistent Pain.

OBJECTIVES: Sensory modulation patterns contribute to altered pain perception and disengagement in activities; atypical sensory modulation patterns have been associated with higher pain sensitivity, catastrophizing, and reduced function. Objectives of this study were to ascertain whether: adolescents with persistent pain had atypical sensory modulation patterns, atypical sensory modulation was associated with reduced functioning and higher pain, and pain catastrophizing mediated the relationship between sensory modulation and functional disability. METHODS: Adolescents (N=70, females=63, males=7) attending tertiary level interdisciplinary team assessment for persistent pain completed sensory modulation (Adolescent/Adult Sensory Profile), pain catastrophizing (Bath Adolescent Pain Questionnaire), pain intensity, functional disability (Functional Disability Index), and quality of life (QOL) (Pediatric QOL Scales) questionnaires. RESULTS: Adolescents with persistent pain had atypical patterns of sensory modulation compared with normative data. Sensory modulation patterns were not associated with pain intensity; however, higher sensitivity was associated with greater disability (r=0.36, P<0.01), and lower registration of sensation was associated with poorer emotional (r=0.31, P<0.01), social (r=0.35, P<0.01), and school-related (r=0.49, P<0.001) QOL. Sensory modulation, pain intensity, and catastrophizing contributed independently to disability; catastrophizing mediated sensory sensitivity and both functional disability and emotional QOL. DISCUSSION: This study is the first to show that atypical sensory modulation patterns are associated with poorer function for adolescents with persistent pain, suggesting that individualized sensory-informed interventions can potentially facilitate participation in daily activities and improve QOL.

Is spinal anaesthesia in young infants really safer and better than general anaesthesia?

PURPOSE OF REVIEW: Concerns regarding the potential neurotoxic effects of general anaesthesia have seen resurgence in awake spinal anaesthesia in neonates and infants. This review includes recently published data from a large prospective randomized controlled trial with view to determining if spinal anaesthesia is safer and better than general anaesthesia in this population. RECENT FINDINGS: Compared with general anaesthesia, spinal anaesthesia results in less haemodynamic instability and fewer early (<30 min) apnoeic episodes in neonates and infants undergoing inguinal herniorraphy; the overall incidence of apnoeas in the first 12 h postoperatively was similar. Neurodevelopmental outcome 2 years postoperatively was similar. An appreciable failure rate for spinal anaesthesia was confirmed. SUMMARY: Spinal anaesthesia represents a suitable alternative to general anaesthesia in neonates and infants undergoing minor surgery avoiding the need for endotracheal intubation and ventilation. Spinal anaesthesia has some advantages but a significant failure rat and has not been demonstrated to improve neurodevelopmental outcome.

Child and Family Antecedents of Pain During the Transition to Adolescence: A Longitudinal Population-Based Study.

Pediatric persistent pain is associated with poorer physical and psychosocial functioning in children, as well as immediate and long-term societal costs. Onset typically occurs in early adolescence, suggesting that late childhood is a key window for identifying potential intervention targets before pain symptoms become entrenched. This study used population-based data from the Longitudinal Study of Australian Children (n = 3,812) and adopted a biopsychosocial and ecological systems approach to investigate child, family, and sociodemographic factors associated with pain problems in children transitioning to adolescence. The prevalence of at least weekly parent-reported pain in the study sample was approximately 5% at 10 to 11 years of age, and pain continued at 12 to 13 years of age for 40% of these children. Key factors at 10 to 11 years that uniquely predicted parent-reported pain problems at 12 to 13 years were frequency of previous pain (1-3 times weekly: odds ratio [OR] = 7.49; 95% confidence interval [CI], 4.3-13.0; 4-7 times weekly: OR = 17.8; 95% CI, 8.7-36.5) and sleep difficulties (OR = 1.86; 95% CI, 1.16-2.97). This study highlights the importance of early intervention for persistent pain in childhood, because pain complaints in late childhood tend to persist into early adolescence. PERSPECTIVE: This article used a biopsychosocial and ecological systems approach to understanding predictors of pain problems during the transition to adolescence within a nationally representative community-based cohort. Sleep difficulties at 10 to 11 years uniquely predicted pain at ages 12 to 13 years, suggesting that early intervention using sleep interventions may be a promising direction for future research.

Comparison of lumbar epidural bupivacaine with fentanyl or clonidine for postoperative analgesia in children with cerebral palsy after single-event multilevel surgery.

AIM: To compare diazepam use, muscle spasm, analgesia, and side effects when clonidine or fentanyl are added to epidural bupivacaine in children with cerebral palsy after multilevel orthopaedic surgery. METHOD: Fifty children were prospectively randomized to receive clonidine (n=24, mean age 10y 10mo [SD 2y 11mo]) or fentanyl (n=26, mean age 10y 11mo [SD 2y 10mo]). RESULTS: There was no difference in primary outcome measures: median diazepam use (fentanyl 0, interquartile range [IQR] 0-0; clonidine 0, IQR 0-0; p=0.46), any muscle spasm (no muscle spasms in: fentanyl, 36%; clonidine, 62%; p=0.11), painful muscle spasm (fentanyl 40%; clonidine 25%; p=0.46), or pain score ≥6 (none: fentanyl 44%; clonidine 42%; p=0.29). There were differences in secondary outcome measures: no vomiting (clonidine 63%; fentanyl 20%); vomiting occurred more frequently with fentanyl (32% vomited more than three times; clonidine none; p=0.001). Fentanyl resulted in more oxygen desaturation (at least two episodes: fentanyl 20%; clonidine 0; p<0.001). Clonidine resulted in lower mean (SD) area under the curve for systolic blood pressure (fentanyl 106.5 [11.0]; clonidine 95.7mmHg [7.9]) and heart rate (fentanyl 104.9 beats per minute [13.6]; clonidine 85.3 [11.5]; p<0.001). INTERPRETATION: Clonidine and fentanyl provide adequate analgesia with low rates of muscle spasm, resulting in low diazepam use. The choice of epidural additive should be based upon the most tolerable side-effect profile.

Post-thoracotomy pain in children and adolescence: a retrospective cross-sectional study.

OBJECTIVE: We sought to determine the prevalence of chronic post-thoracotomy pain, defined as persistent or recurring incisional pain for at least 2 months after thoracotomy, in children. DESIGN: Retrospective cross-sectional study. SETTING: Quaternary pediatric teaching hospital. SUBJECTS: Patients who underwent a lateral thoracotomy from January 2005 to December 2007 at the Royal Children's Hospital, Melbourne, Australia. METHODS: Eligible patients were sent a questionnaire for telephonic completion with a researcher, with assistance from the parents if required. RESULTS: Of the 87 patients eligible to participate, 51 (59%) completed questionnaires. The majority of respondents was male (65%), underwent a single thoracotomy (84%; range 1-3), and were non-elective operations (71%). The median age at first thoracotomy was 5.7 (interquartile range [IQR] 2-14.2) years. The median age at questionnaire completion was 9.0 (IQR 5.4-17.9) years, with 3.6 (IQR 2.8-4.1) years between thoracotomy and time of questionnaire completion. Three patients (6%) scored ≥12 on self-report versions of the Leeds Assessment of Neuropathic Symptoms and Signs pain scale. Of these, only one patient complained of current post-thoracotomy pain. All three patients had a single thoracotomy and were older (mean age 14.2 years) at the time of thoracotomy. The rate of post-thoracotomy pain calculated using the binomial exact method is 1.96% (95% confidence interval 0-10.4%). CONCLUSIONS: Our study reports a low prevalence of post-thoracotomy pain in childhood and adolescence, and stands in contrast to previously published adult data.

Effective postoperative pain management in children after ambulatory surgery, with a focus on tonsillectomy: barriers and possible solutions.

Pain following ambulatory surgery is often poorly managed at home. Certain procedures, such as tonsillectomy, cause high levels of pain for at least 1 week postoperatively. This impacts significantly on recovery and postoperative morbidity with regards to oral intake, sleep, and behavior. Barriers to effective postoperative pain management at home following discharge have been investigated and incorporate: parental factors, such as the ability to recognize and assess their child's pain, and misconceptions about analgesics; child factors, such as refusal to take medication; medication factors, such as ineffective medication or inadequate formulation or dose of analgesics; and system factors, such as poor discharge instructions, difficulty in obtaining medication and lack of information provision. A number of interventions have been suggested and trialled in an effort to address these barriers, which encompass educational strategies, improved information provision, improved medication regimens, and the provision of tools to aid parents in the pain management of their children. All in all, improvements in pain outcomes have been minor, and a more holistic approach, that appreciates the complex and multifaceted nature of pain management at home, is required.

Absorption characteristics of epidural levobupivacaine with adrenaline and clonidine in children.

AIM: To determine if the addition of adrenaline, clonidine, or their combination altered the pharmacokinetic profile of levobupivacaine administered via the caudal epidural route in children. METHODS: Children aged <18 years old scheduled to undergo sub-umbilical surgery were administered caudal levobupivacaine plain 2.5 mg · ml(-1) or with adjuvants adrenaline 5 mcg · ml(-1) or clonidine 2 mcg · ml(-1) or their combination. Covariate analysis included weight and postnatal age (PNA). Time-concentration profile analysis was undertaken using nonlinear mixed effects models. A one-compartment linear disposition model with first-order input and first-order elimination was used to describe the data. The effect of either clonidine or adrenaline on absorption was investigated using a scaling parameter (Fabs(CLON), Fabs(ADR)) applied to the absorption half-life (Tabs). RESULTS: There were 240 children (median weight 11.0, range 1.9-56.1 kg; median postnatal age 16.7, range 0.6-167.6 months). Absorption of levobupivacaine was faster when mixed with clonidine (Fabs(CLON) 0.60; 95%CI 0.44, 0.83) but slower when mixed with adrenaline (Fabs(ADR) 2.12; 95%CI 1.45, 3.08). The addition of adrenaline to levobupivacaine resulted in a bifid absorption pattern. While initial absorption was unchanged (Tabs 0.15 h 95%CI 0.12, 0.18 h), there was a late absorption peak characterized by a Tabs(LATE) 2.34 h (95%CI 1.44, 4.97 h). The additional use of clonidine with adrenaline had minimal effect on the bifid absorption profile observed with adrenaline alone. Neither clonidine nor adrenaline had any effect on clearance. The population parameter estimate for volume of distribution was 157 l 70 kg(-1). Clearance was 6.5 l · h(-1) 70 kg(-1) at 1-month PNA and increased with a maturation half-time of 1.6 months to reach 90% of the mature value (18.5 l · h(-1) 70 kg(-1)) by 5 months PNA. CONCLUSIONS: The addition of adrenaline decreases the rate of levobupivacaine systemic absorption, reducing peak concentration by half. Levobupivacaine concentrations with adrenaline adjuvant were reduced compared to plain levobupivacaine for up to 3.5 hours. Clonidine as an adjuvant results in faster systemic absorption of levobupivacaine and similar concentration time profile to levobupivacaine alone. Adding adrenaline with clonidine does not alter the concentration profile observed with adrenaline alone.

Audit of extrapleural local anaesthetic infusion in neonates following repair of tracheo-oesophageal fistulae and oesophageal atresia via thoracotomy.

In order to reduce postoperative opioid requirement, extrapleural local anaesthetic infusion dosing recommendations and guidelines for extrapleural catheter insertion were developed in our institution for 'extubatable' neonates requiring short-gap neonatal tracheo-oesophageal fistula/oesophageal atresia repair (via thoracotomy) and audited prospectively. Data audited included patient characteristics, analgesia details and ventilation duration. We divided patients into two groups: group 1 - term patients (=36 weeks gestational age) with birth-weights =2.5 kg; group 2 - pre-term patients (<36 weeks gestational age), with birth weights <2.5 kg and those with co-morbidities. There were 26 neonates in group 1 and 11 in group 2. All received extrapleural infusions of bupivacaine or levobupivacaine: the majority (90%) =300 µg.kg(-1).hour(-1) (median duration 43 hours, range 1.5 to 72 hours); 36% required morphine infusion and 39% were ventilated (median duration 34 hours, range 3 to 140 hours). In group 1, 24% required morphine infusion compared with 64% in group 2. Most group 1 patients (77%) were extubated immediately postoperatively; 20% had short duration ventilation (median 15 hours, range 11 to 37 hours); one required longer-term ventilation (231 hours). 82% of group 2 were ventilated for a median of 72 hours (range 3 to 140 hours). Review of patients' co-morbidities facilitated guideline revision. These now specify use in neonates requiring short-gap tracheo-oesophageal fistula/oesophageal atresia repair who are term at =36 weeks gestational age and =2.5 kg birth-weight, anticipated as ready for extubation either immediately or shortly after surgery.

The severity and duration of postoperative pain and analgesia requirements in children after tonsillectomy, orchidopexy, or inguinal hernia repair.

OBJECTIVES: To provide parents of children with accurate information regarding postoperative pain, its management, and functioning following common surgical procedures. BACKGROUND: The increasing prevalence of pediatric day-case procedures demands a more thorough understanding of the recovery profiles associated with these operations. AIM: To document postdischarge pain profiles, analgesia requirements, and functional limitation in children following tonsillectomy, orchidopexy, or inguinal hernia repair (IHR). METHODS: Following hospital discharge, parents were asked to record their children's pain levels, analgesia consumption, and degree of functional limitation each day until complete recovery. Pain and functional limitation were measured using the Parents' Postoperative Pain Measurement (PPPM) scale and Functional Activity Score, respectively. Significant pain was defined as PPPM ≥ 6. RESULTS: One hundred and five patients (50, tonsillectomy; 24, orchidopexy; and 31, IHR) were recruited. Median PPPM was always <6 after IHR, ≥6 only on day 1 after orchidopexy and persisted through to day 8 after tonsillectomy. Mild or severe functional limitation was observed after all surgeries and persisted for 4, 5, and 4 days after median PPPM < 6 after IHR, orchidopexy, and tonsillectomy, respectively. Combination analgesia was commonly administered after orchidopexy and tonsillectomy but less so after IHR. The general practitioner consultation rate following tonsillectomy was 54%. CONCLUSIONS: After tonsillectomy, children experience significant pain and severe functional limitation for 7 days after surgery. For many children, pain and functional limitation persists throughout the second postoperative week. In children undergoing orchidopexy, paracetamol and ibuprofen provide adequate analgesia. Pain begins to subside after the first postoperative day, and normal activity resumes after 7 days. After IHR, children experience mild pain that can be treated with paracetamol and return to normal functioning after 4 days.

A case of sympathetically mediated headache treated with stellate ganglion blockade.

BACKGROUND: Chronic pain following trauma may be mediated in part by the sympathetic nervous system. There is evidence of sympathetic nervous system dysfunction in patients who suffer from posttraumatic headaches. Not all patients will obtain relief from conventional and antineuropathic medications. Furthermore, the development of adverse effects may limit therapeutic dosing or continuation of these medications. CASE REPORT: A pediatric case of posttraumatic headache is described. The patient failed medical therapy, and a single stellate ganglion blockade was performed for possible sympathetic involvement. Following sympathetic blockade, the patient's headaches resolved completely. The analgesia proved to be long lasting as the patient reported no further headaches at monthly follow-up intervals. The patient did not require any further analgesic medication after the single procedure. CONCLUSION: Posttraumatic headache is difficult to treat. Although there is evidence of sympathetic nervous system dysfunction in some patients, the extent to which this influences pain remains to be determined. While most cases are treated with a combination of nonpharmacological and pharmacological measures, sympathetic blockade via the stellate ganglion may be an alternative for those patients not responding to conventional therapy.

Sex differences in pain intensity in adolescents suffering from cancer: differences in pain memories?

UNLABELLED: Although sex differences have been investigated in chronic pain populations, little is known about sex differences in the pain experience of paediatric oncology patients and also whether their parents rate the pain experience differently for boys and girls. The aim of the present study was to determine if (1) boys and girls with cancer differ in current perception and past recollection of cancer-related pain and (2) if adolescents' and parents' pain ratings differ in relation to the sex of the adolescent. One hundred twelve adolescents with malignant diagnoses (12 to 18 years) and their parents participated in the study. Girls reported higher pain intensity within the last 7 days and 4 weeks despite similar diagnosis, physical status, duration of diagnoses, and main pain causes. When asked for pain intensity that dated back in time, parent and adolescent ratings diverged, with a trend for parents to reporting higher pain intensity in boys and lower pain intensity in girls, particularly for pain in the preceding 7 days. The present study provides preliminary evidence for sex differences in the recalled pain experience of adolescents with malignant diagnoses. Although boys and girls experience present pain similarly and hence should be treated similarly, girls recall higher pain intensity than boys. Future studies should address whether negative memories in girls play a significant role and may have an impact on girls' well-being and pain-related distress. Additionally, psychosocial factors such as gender role expectations may need to be investigated. Parental variables and their impact on parents' pain ratings, especially for ratings of precedent pain, warrants further investigation. PERSPECTIVE: Girls with malignant diagnoses differ from boys in their recalled pain intensity ratings, with girls reporting higher pain intensity. Additional pain management strategies referring to the memory of pain may need to be implemented.

Does epidural analgesia delay the diagnosis of lower limb compartment syndrome in children?

One of the cardinal symptoms of compartment syndrome is pain. A literature review was undertaken in order to assess the association of epidural analgesia and compartment syndrome in children, whether epidural analgesia delays the diagnosis, and to identify patients who might be at risk. Evidence was sought to offer recommendations in the use of epidural analgesia in patients at risk of developing compartment syndrome of the lower limb. Increasing analgesic use, increasing/breakthrough pain and pain remote to the surgical site were identified as important early warning signs of impending compartment syndrome in the lower limb of a child with a working epidural. The presence of any should trigger immediate examination of the painful site, and active management of the situation (we have proposed one clinical pathway). Avoidance of dense sensory or motor block and unnecessary sensory blockade of areas remote to the surgical site allows full assessment of the child and may prevent any delay in diagnosis of compartment syndrome. Focusing on excluding the diagnosis of compartment syndrome rather than failure of analgesic modality is vital. In the pediatric cases reviewed there was no clear evidence that the presence of an epidural had delayed the diagnosis.

Clinically unrecognized intravascular placement of epidural catheter in a child--an argument for the use of radio-opaque contrast?

An epidural catheter was inserted after induction of anesthesia in a 28.2 kg 9-year-old boy scheduled to undergo bilateral femoral varus derotational osteotomies. There was no gravity free flow of blood down the catheter and there was no blood aspirated with a 2 ml syringe. After a negative test dose of a 4 ml solution of 0.25% levobupivacaine with epinephrine 1 : 200 000, a further 8 ml was administered via the epidural catheter. No significant increase in heart rate was noted. On surgical skin incision the heart rate increased from 94 to 116 b.min(-1) and blood pressure increased from 104/44 to 116/46 mmHg. A further 3 ml 0.25% levobupivacaine with epinephrine and clonidine 2 mug.kg(-1) were administered via the epidural catheter. The operation continued uneventfully although it was noted that the heart rate increased intermittently during the procedure. In view of the unexplained tachycardia and a history of cerebral palsy with the potential for postoperative muscle spasms, it was felt important to have a reliable epidural. To confirm placement, 2 ml of Isovue 300 (Iopamidol) was administered via the epidural catheter. X-ray screening demonstrated intravascular placement and the rapid disappearance of contrast. The catheter was removed and reinserted. Contrast demonstrated good spread in the epidural space. The merits of screening with contrast for epidural catheter placement in children are discussed.

Age and size are the major covariates for prediction of levobupivacaine clearance in children.

BACKGROUND: We aimed to identify and quantify major factors describing the variability of levobupivacaine clearance in children. METHODS: Data from three published studies were used to estimate population pharmacokinetics of levobupivacaine in children who were given epidural regional blockade. Covariate analysis included weight and postnatal age (PNA). Time-concentration profile analysis was undertaken using nonlinear mixed effects models. A one-compartment linear disposition model with first order input and first order elimination was used to describe the data. RESULTS: There were 86 children (weight 9.4, sd 5.5, range 1.9-23 kg; PNA 16.1, sd 22.7, range 0.6-98 months). The population parameter estimate for volume of distribution (V) was 189 l.70 kg(-1). Clearance (CL) was 5.8 l.h(-1).70 kg(-1) at 1-month PNA and increased with a maturation half-time of 2.3 months to reach 80% of the mature value (22.1 l.h(-1).70 kg(-1)) by 6-month PNA. The between subject variability (BSV) for V and CL were 48.5% and 35.2%. Overall, 85.7% of the variability of CL was predictable. Weight alone explained 62.4% and the addition of PNA a further 23.3%. Overall, 69.2% of the variability of V was predictable and attributable to weight; V did not change with age in this cohort. The absorption half-time decreased from 0.36 h at 1-month PNA to 0.14 h (CV 48.1%) at 6-month PNA with a maturation half-time of 0.8 months. CONCLUSIONS: Size and PNA are the major contributors to clearance variability in children. These covariates should be considered when establishing safe epidural infusion regimens. Reduced clearance and slower absorption half-time contribute to delayed T(max) in neonates and young infants.