Twenty-four-hour pharmacokinetics of rectal acetaminophen in children: an old drug with new recommendations

Efficacy of different routes of acetaminophen administration for postoperative pain in children: a systematic review and network meta-analysis

PURPOSE

Acetaminophen is the most common drug used to treat acute pain in the pediatric population, given its wide safety margin, low cost, and multiple routes for administration. We sought to determine the most efficacious route of acetaminophen administration for postoperative acute pain relief in the pediatric surgical population.

METHODS

We conducted a systematic review of randomized controlled trials (RCTs) that included children aged between 30 days and 17 yr who underwent any type of surgical procedure and that evaluated the analgesic efficacy of different routes of administration of acetaminophen for the treatment of postoperative pain. We searched MEDLINE, CENTRAL, Embase, CINAHL, LILACs, and Google Scholar databases for trials published from inception to 16 April 2023. We assessed the risk of bias in the included studies using the Cochrane Risk of Bias 1.0 tool. We performed a frequentist network meta-analysis using a random-effects model. Our primary outcome was postoperative pain using validated pain scales.

RESULTS

We screened 2,344 studies and included 14 trials with 829 participants in the analysis. We conducted a network meta-analysis for the period from zero to two hours, including six trials with 496 participants. There was no evidence of differences between intravenous vs rectal routes of administration of acetaminophen (difference in means, -0.28; 95% confidence interval [CI], -0.62 to 0.06; very low certainty of the evidence) and intravenous vs oral acetaminophen (difference in means, -0.60; 95% CI, -1.20 to 0.01; low certainty of the evidence). For the comparison of oral vs rectal routes, we found evidence favouring the oral route (difference in means, -0.88; 95% CI, -1.44 to -0.31; low certainty of the evidence). Few trials reported secondary outcomes of interest; when comparing the oral and rectal routes in the incidence of nausea and vomiting, there was no evidence of differences (relative risk, 1.20; 95% CI, 0.81 to 1.78).

CONCLUSION

The available evidence on the effect of the administration route of acetaminophen on postoperative pain in children is very uncertain. The outcomes of postoperative pain control and postoperative vomiting may differ very little between the oral and rectal route. Better designed and executed RCTs are required to address this important clinical question.

STUDY REGISTRATION

PROSPERO (CRD42021286495); first submitted 19 November 2021.

The Three W's of Acetaminophen In Children: Who, Why, and Which Administration Mode

Acetaminophen is one of the oldest medications commonly administered in children. Its efficacy in treating fever and pain is well accepted among clinicians. However, the available evidence supporting the use of acetaminophen's different modes of administration remains relatively scarce and poorly known. This short report summarizes the available evidence and provides a framework to guide clinicians regarding a rational use of acetaminophen in children.

Analgesic use and favourable patient-reported outcome measures after paediatric surgery: an analysis of registry data

BACKGROUND

Pain after paediatric appendectomy and tonsillectomy is often undertreated. Benchmarking of hospitals could reveal which measures are associated with improved patient- or parent-reported pain-related outcomes.

METHODS

A total of 898 anonymised cases from 11 European hospitals participating in PAIN OUT infant were analysed. The children completed a questionnaire on patient-reported outcomes (PROs) 24 h after surgery. According to a composite PRO measure, including pain intensity and pain-related interference, hospitals were allocated to Group I (favourable results), II (average results), and III (unfavourable results). Benchmarking of hospital groups was performed investigating process variables (dosing of non-opioid analgesics, opioids, and dexamethasone) associated with PROs, side-effects, and children's perception of care. Variables associated with PROs were analysed using multinomial regression analysis with the PRO score-related hospital group as a dependent variable (estimated odds ratios [OR], 95% confidence interval [CI]).

RESULTS

During the first 24 h after surgery, 1.2 (1.1-1.3) full daily doses of non-opioid analgesics (non-steroidal anti-inflammatory drug [NSAID], paracetamol, metamizole) were administered in group I and 0.7 (0.6-0.8) in group III (P<0.001). Intraoperative dexamethasone was administered to 70.1 and 52.6% of the children in Group I and Group III, respectively (P<0.001). A lower number of full daily doses of non-opioid analgesics: 0.22 [0.15-0.31]), less dexamethasone (0.49 [0.33-0.71]), fewer non-opioid analgesics before the end of surgery (0.37 [0.22-0.62]) and higher opioid doses were associated with hospital allocation to group III vs group I (Nagelkerke's R²=0.433).

CONCLUSIONS

The results indicated substantial deficits in the concept, application, and dosing of analgesics in paediatric patients after surgery. Timely administration of adequate analgesic doses can easily be introduced into daily clinical practice.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov NCT02083835.

Paracetamol (acetaminophen) use in infants and children was never shown to be safe for neurodevelopment: a systematic review with citation tracking

Although widely believed by pediatricians and parents to be safe for use in infants and children when used as directed, increasing evidence indicates that early life exposure to paracetamol (acetaminophen) may cause long-term neurodevelopmental problems. Furthermore, recent studies in animal models demonstrate that cognitive development is exquisitely sensitive to paracetamol exposure during early development. In this study, evidence for the claim that paracetamol is safe was evaluated using a systematic literature search. Publications on PubMed between 1974 and 2017 that contained the keywords "infant" and either "paracetamol" or "acetaminophen" were considered. Of those initial 3096 papers, 218 were identified that made claims that paracetamol was safe for use with infants or children. From these 218, a total of 103 papers were identified as sources of authority for the safety claim.   Conclusion: A total of 52 papers contained actual experiments designed to test safety, and had a median follow-up time of 48 h. None monitored neurodevelopment. Furthermore, no trial considered total exposure to drug since birth, eliminating the possibility that the effects of drug exposure on long-term neurodevelopment could be accurately assessed. On the other hand, abundant and sufficient evidence was found to conclude that paracetamol does not induce acute liver damage in babies or children when used as directed. What is Known: • Paracetamol (acetaminophen) is widely thought by pediatricians and parents to be safe when used as directed in the pediatric population, and is the most widely used drug in that population, with more than 90% of children exposed to the drug in some reports. • Paracetamol is known to cause liver damage in adults under conditions of oxidative stress or when used in excess, but increasing evidence from studies in humans and in laboratory animals indicates that the target organ for paracetamol toxicity during early development is the brain, not the liver. What is New: • This study finds hundreds of published reports in the medical literature asserting that paracetamol is safe when used as directed, providing a foundation for the widespread belief that the drug is safe. • This study shows that paracetamol was proven to be safe by approximately 50 short-term studies demonstrating the drug's safety for the pediatric liver, but the drug was never shown to be safe for neurodevelopment. Paracetamol is widely believed to be safe for infants and children when used as directed, despite mounting evidence in humans and in laboratory animals indicating that the drug is not safe for neurodevelopment. An exhaustive search of published work cited for safe use of paracetamol in the pediatric population revealed 52 experimental studies pointing toward safety, but the median follow-up time was only 48 h, and neurodevelopment was never assessed.

Management of acute fever in children: Consensus recommendations for community and primary healthcare providers in sub-Saharan Africa

Fever is one of the most common reasons for unwell children presenting to pharmacists and primary healthcare practitioners. Currently there are no guidelines for assessment and management of fever specifically for community and primary healthcare workers in the sub-Saharan Africa region. This multidisciplinary consensus guide was developed to assist pharmacists and primary healthcare workers in sub-Saharan Africa to risk stratify and manage children who present with fever, decide when to refer, and how to advise parents and caregivers. Fever is defined as body temperature ≥ 37.5 °C and is a normal physiological response to illness that facilitates and accelerates recovery. Although it is often associated with self-limiting illness, it causes significant concern to both parents and attending healthcare workers. Clinical signs may be used by pharmacy staff and primary healthcare workers to determine level of distress and to distinguish between a child with fever who is at high risk of serious illness and who requires specific treatment, hospitalisation or specialist care, and those at low risk who could be managed conservatively at home. In children with warning signs, serious causes of fever that may need to be excluded include infections (including malaria), non-infective inflammatory conditions and malignancy. Simple febrile convulsions are not in themselves harmful, and are not necessarily indicative of serious infection. In the absence of illness requiring specific treatment, relief from distress is the primary indication for prescribing pharmacotherapy, and antipyretics should not be administered with the sole intention of reducing body temperature. Care must be taken not to overdose medications and clear instructions should be given to parents/caregivers on managing the child at home and when to seek further medical care.

Opioids in the Management of Acute Pediatric Pain: An Update in a Time of Crisis

Management of acute pain in children is fundamental to our practice. Its myriad benefits include reduced suffering, improved patient satisfaction, more rapid recovery, and a reduced risk of developing postsurgical chronic pain. Although a multimodal analgesic approach is now routinely used, informed and judicious use of opioid receptor agonists remains crucial in this treatment paradigm, as long as the benefits and risks are fully understood. Further, an ongoing public health response to the current opioid crisis is required to help prevent new cases of opioid addiction, identify opioid-addicted individuals, and ensure access to effective opioid addiction treatment, while at the same time continuing to safely meet the needs of patients experiencing pain.

Acetaminophen pharmacokinetics in severely obese adolescents and young adults

BACKGROUND

Intravenous acetaminophen is commonly administered as an adjunctive to opioids during major surgical procedures, but neither the correct pharmacokinetic size descriptor nor the dose is certain in severely obese adolescents undergoing bariatric surgery.

METHODS

Adolescents, 14-20 years of age, with a body mass index (BMI) ≥95th percentile for age and sex or BMI ≥40 kg·m^-2 , presenting for laparoscopic or robotic assisted or vertical sleeve gastrectomy were administered intravenous acetaminophen (1000 mg) following completion of the surgical procedure. Venous blood was drawn for acetaminophen assay at eight time points, starting 15 minutes after completion of the infusion and up to 12 hours afterward. Time-concentration data profiles were analyzed using nonlinear mixed effects models. Parameter estimates were scaled to a 70-kg person using allometry. Normal fat mass was used to assess the impact of obesity on pharmacokinetic parameters.

RESULTS

The study cohort comprised 11 female patients, age 17 SD 2 years with a weight of 125 SD 19 kg and a mean BMI of 46 SD 5 kg·m^-2 . The plasma acetaminophen serum concentration was 17 (SD 4) μg·mL^-1 at 10-20 minutes after completion of the infusion and 5 (SD 6) μg·mL^-1 at 80-100 minutes. A two-compartment model, used to investigate pharmacokinetics, estimated clearance 10.6 (CV 72%) L·h·70 kg^-1 , intercompartment clearance 37.3 (CV 63%) L·h·70 kg^-1 , central volume of distribution 20.4 (CV 46%) L·70 kg^-1 , and peripheral volume of distribution 16.8 (CV 42%) L·70 kg^-1 . Clearance was best described using total body weight. Normal fat mass with a parameter that accounts for fat mass contribution (Ffat) of 0.88 best described volumes.

CONCLUSION

Current recommendations of acetaminophen to a maximum dose of 1000 mg resulted in serum concentrations below detection limits in all patients within 2 hours after administration. Dose is better predicted using total body mass with allometric scaling.

Comparison of Antipyretic Efficacy of Intravenous (IV) Acetaminophen versus Oral (PO) Acetaminophen in the Management of Fever in Children

OBJECTIVE

To assess the dynamics of the onset of antipyretic efficacy of intravenous (IV) acetaminophen vs. oral (PO) acetaminophen in the management of fever in children.

METHODS

This observational single-dose study was conducted at Department of Pedriatrics, Army Hospital (Research and Referral), a multispecialty tertiary care center in New Delhi in fever patients to assess the antipyretic efficacy of IV acetaminophen 15 mg/kg/dose vs. PO acetaminophen 15 mg/kg/dose over 6 h. Subjects were randomly assigned to receive either IV acetaminophen (n = 200) or PO acetaminophen (n = 200).

RESULTS

Demographics and baseline characteristics were similar between the two groups and were normally distributed. Allergic reaction was found in 7 (3.5%) patients in IV acetaminophen group and was absent in PO acetaminophen group. Onset of constipation and dry mouth was found in 8 patients (4%) in IV acetaminophen group and was absent in PO acetaminophen group. Additional dose was required in 6 patients (3%) in intravenous acetaminophen group and 10 patients (5%) in oral acetaminophen group respectively. Statistically significant differences in the rate of fall in temperature through 180 min were observed in favor of the IV acetaminophen group when compared to those receiving PO acetaminophen.

CONCLUSIONS

A single dose of intravenous acetaminophen is safe and effective in reducing fever where patients are unable to tolerate oral administration or when rapid reduction of temperature is desirable.

Paracetamol and morphine for infant and neonatal pain; still a long way to go?

INTRODUCTION

Pharmacologic pain management in newborns and infants is often based on limited scientific data. To close the knowledge gap, drug-related research in this population is increasingly supported by the authorities, but remains very challenging. This review summarizes the challenges of analgesic studies in newborns and infants on morphine and paracetamol (acetaminophen). Areas covered: Aspects such as the definition and multimodal character of pain are reflected to newborn infants. Specific problems addressed include defining pharmacodynamic endpoints, performing clinical trials in this population and assessing developmental changes in both pharmacokinetics and pharmacodynamics. Expert commentary: Neonatal and infant pain management research faces two major challenges: lack of clear biomarkers and very heterogeneous pharmacokinetics and pharmacodynamics of analgesics. There is a clear call for integral research addressing the multimodality of pain in this population and further developing population pharmacokinetic models towards physiology-based models.

Enduring large use of acetaminophen suppositories for fever management in children: a national survey of French parents and healthcare professionals' practices

The pharmacological specificities of the rectal formulation of acetaminophen led to a debate on its appropriateness for managing fever in children, but few data are available on the formulation's current use and determinants of use. In a national cross-sectional study between 2007 and 2008, healthcare professionals were asked to include five consecutive patients with acute fever. Among the 6255 children (mean age 4.0 years ± 2.8 SD) who received acetaminophen given by parents or prescribed/recommended by healthcare professionals, determinants of suppository use were studied by multilevel models. A suppository was given by 27 % of parents and prescribed/recommended by 19 % of healthcare professionals, by 24 and 16 %, respectively, for children 2 to 5 years old, and by 13 and 8 %, respectively, for those 6 to 12 years old. Among children who received suppositories from parents and healthcare professionals, 83 and 84 %, respectively, did not vomit. Suppository use was independently associated with several patient- and healthcare professional-level characteristics: young age of children, presence of vomiting, or lack of diarrhea.

CONCLUSION

We report an enduring large use of suppositories in France for the symptomatic management of fever in children, including in non-vomiting and/or older children. The rational for such use should be questioned.

WHAT IS KNOWN

• The pharmacological specificities of the rectal formulation of acetaminophen have led to a debate on its appropriateness for managing fever in children. Few data are available on the formulation's current use and determinants of the use. What is New: • In a national cross-sectional study, we observed a large use of suppositories in France for symptomatic management of fever in children. Suppositories were frequently used for the youngest children but also for older and/or non-vomiting children.

Treatment of Pain in Pediatric Patients

A growing body of evidence demonstrates that untreated pain is associated with adverse consequences that can compromise clinical and developmental outcomes in children but that these adverse consequences can be prevented or attenuated by appropriate analgesic therapy. Thus, effective treatment of acute pain must be a clinical priority for children of all ages. Over the past 20 years, extensive pediatric research exploring pain assessment, developmental pharmacology of analgesics, and the clinical use of analgesics has dispelled many myths and misconceptions about pain management in pediatric patients; proven that analgesics can be used safely in neonates, infants, and children; and provided a framework for the development of pediatric pain management guidelines. This article reviews guidelines recommended for managing acute pain in pediatric patients and the treatment options for children experiencing acute pain. Contemporary issues regarding acetaminophen, nonsteroidal anti-inflammatory agents, and opioids are discussed.

Perioperative care of infants with pyloric stenosis

Pyloric stenosis (PS) is one of the most common surgical conditions affecting neonates and young infants. The definitive treatment for PS is surgical pyloromyotomy, either open or laparoscopic. However, surgical intervention should never be considered urgent or emergent. More importantly, emergent medical intervention may be required to correct intravascular volume depletion and electrolyte disturbances. Given advancements in surgical and perioperative care, morbidity and mortality from PS should be limited. However, either may occur related to poor preoperative resuscitation, anesthetic management difficulties, or postoperative complications. The following manuscript reviews the current evidence-based medicine regarding the perioperative care of infants with PS with focus on the preoperative assessment and correction of metabolic abnormalities, intraoperative care including airway management (particularly debate related to rapid sequence intubation), maintenance anesthetic techniques, and techniques for postoperative pain management. Additionally, reports of applications of regional anesthesia for either postoperative pain control or as an alternative to general anesthesia are discussed. Management recommendations are provided whenever possible.

Neonatal pain management

The past 2-3 decades have seen dramatic changes in the approach to pain management in the neonate. These practices started with refuting previously held misconceptions regarding nociception in preterm infants. Although neonates were initially thought to have limited response to painful stimuli, it was demonstrated that the developmental immaturity of the central nervous system makes the neonate more likely to feel pain. It was further demonstrated that untreated pain can have long-lasting physiologic and neurodevelopmental consequences. These concerns have resulted in a significant emphasis on improving and optimizing the techniques of analgesia for neonates and infants. The following article will review techniques for pain assessment, prevention, and treatment in this population with a specific focus on acute pain related to medical and surgical conditions.

The postoperative management of pain from intracranial surgery in pediatric neurosurgical patients

Pain following intracranial surgery has historically been undertreated because of the concern that opioids, the analgesics most commonly used to treat moderate-to-severe pain, will interfere with the neurologic examination and adversely affect postoperative outcome. Over the past decade, accumulating evidence, primarily in adult patients, has revealed that moderate-to-severe pain is common in neurosurgical patients following surgery. Using the neurophysiology of pain as a blueprint, we have highlighted some of the drugs and drug families used in multimodal pain management. This analgesic method minimizes opioid-induced adverse side effects by maximizing pain control with smaller doses of opioids supplemented with neural blockade and nonopioid analgesics, such nonsteroidal antiinflammatory drugs, local anesthetics, corticosteroids, N-methyl-D-aspartate (NMDA) antagonists, α2 -adrenergic agonists, and/or anticonvulsants (gabapentin and pregabalin).

Acute pain management in infants and children-Part 1: Pain pathways, pain assessment, and outpatient pain management

The field of pediatric pain management continues to evolve, with ongoing changes in our appreciation of the impact of pain on our fragile patients, a better understanding of how to assess pain, and refinements of the medications and techniques used to provide analgesia to patients with acute pain of various etiologies. The following article reviews the techniques for the assessment of pain, including various age-specific pain scoring systems. The pharmacological management of pain is discussed, including the use of agents that inhibit prostaglandin formation-nonsteroidal anti-inflammatory agents and acetaminophen-as well as the "weak opioids" that are commonly used when oral administration is feasible for the treatment of mild to moderate pain.

Rectal route in the 21st Century to treat children

The rectal route can be considered a good alternative to the oral route for the paediatric population because these dosage forms are neither to be swallowed nor need to be taste-masked. Rectal forms can also be administered in an emergency to unconscious or vomiting children. Their manufacturing cost is low with excipients generally regarded as safe. Some new formulation strategies, including mucoadhesive gels and suppositories, were introduced to increase patient acceptability. Even if recent paediatric clinical studies have demonstrated the equivalence of the rectal route with others, in order to enable the use of this promising route for the treatment of children in the 21st Century, some effort should be focused on informing and educating parents and care givers. This review is the first ever to address all the aforementioned items, and to list all drugs used in paediatric rectal forms in literature and marketed products in developed countries.

Ring block with levobupivacaine 0.25% and paracetamol vs. paracetamol alone in children submitted to three different surgical techniques of circumcision: A prospective randomized study

Background:

circumcision in children is a painful procedure. We aim compare the intraoperative and postoperative efficacy of three different surgical procedures of the ring block using levobupivacaine 0.25% combined with rectal paracetamol as opposed to rectal paracetamol alone.

Methods:

the study included 106 boys scheduled to undergo circumcision. The patients were randomly assigned within two groups to receive either ring block with levobupivacaine 0.25% and rectal paracetamol 30 mg/kg, or rectal paracetamol 30 mg/kg alone. The following surgical procedures were performed: sutureless proctoplasty, preputial plasty, and conventional circumcision. The efficacy of intraoperative analgesia was estimated on the basis of increases in heart rate and mean arterial pressure. Postoperatively, children were assessed for pain, pain-free (PF) period, and the total doses of analgesics administered during hospitalization, on the day after discharge, and on the first and second postoperative days.

Results:

all children remained stable during anesthesia. Postoperatively, the mean pain score did not show statistical differences between the groups. Children who received combined analgesia had a longer PF period (P < 0.001). However, the total doses of paracetamol administered during the observational period showed no differences. Children undergoing sutureless prepuceplasty received lower doses of paracetamol postoperatively (P < 0.001).

Conclusion:

subcutaneous ring block either with levobupivacaine 0.25% plus rectal paracetamol or rectal paracetamol alone provides adequate intraoperative and postoperative analgesia in circumcised children. However, combined analgesia allows a longer PF period. The need for less analgesic administration in children undergoing sutureless prepuceplasty could mean that the circumcision techniques might be a mitigating factor in terms of pain.

Pain management in neonates

Multiple lines of evidence suggest an increased sensitivity to pain in neonates. Repeated and prolonged pain exposure may affect the subsequent development of pain systems, as well as potentially contribute to alterations in long-term development and behavior. Despite impressive gains in the knowledge of neonatal pain mechanisms and strategies to treat neonatal pain acquired during the last 15 years, a large gap still exists between routine clinical practice and research results. Accurate assessment of pain is crucial for effective pain management in neonates. Neonatal pain management should rely on current scientific evidence more than the attitudes and beliefs of care-givers. Parents should be informed of pain relief strategies and their participation in the health care plan to alleviate pain should be encouraged. The need for systemic analgesia for both moderate and severe pain, in conjunction with behavioral/environmental approaches to pain management, is emphasized. A main sources of pain in the neonate is procedural pain which should always be prevented and treated. Nonpharmacological approaches constitute important treatment options for managing procedural pain. Nonpharmacological interventions (environmental and preventive measures, non-nutritive sucking, sweet solutions, skin-skin contact, and breastfeeding analgesia) can reduce neonatal pain indirectly by reducing the total amount of noxious stimuli to which infants are exposed, and directly, by blocking nociceptive transduction or transmission or by activation of descending inhibitory pathways or by activating attention and arousal systems that modulate pain. Opioids are the mainstay of pharmacological pain treatment but there are other useful medications and techniques that may be used for pain relief. National guidelines are necessary to improve neonatal pain management at the institutional level, individual neonatal intensive care units need to develop specific practice guidelines regarding pain treatment to ensure that all staff are familiar with the effects of the drugs being used and to guarantee access and safe administration of pain treatment to all neonates.

S. Pediatric Otolaryngology

Otolaryngologic procedures are commonly performed on children. In fact, pressure equalizing tube placement (ear tubes) and adenotonsillectomy are among the most frequent surgical interventions in the pediatric population. Therefore, every anesthesiologist who manages children undergoing otolaryngologic procedures must be familiar with the special implications of sharing the pediatric airway with an otolaryngologist working in the head and neck region. In addition, it is imperative to be skilled in the challenges of compassionately yet safely managing anxious young patients and their parents from the time of preoperative assessment until discharge from the post anesthesia care unit.

Protocols in cleft lip and palate treatment: systematic review

Objectives. To find clinical decisions on cleft treatment based on randomized controlled trials (RCTs). Method. Searches were made in PubMed, Embase, and Cochrane Library on cleft lip and/or palate. From the 170 articles found in the searches, 28 were considered adequate to guide clinical practice. Results. A scarce number of RCTs were found approaching cleft treatment. The experimental clinical approaches analyzed in the 28 articles were infant orthopedics, rectal acetaminophen, palatal block with bupivacaine, infraorbital nerve block with bupivacaine, osteogenesis distraction, intravenous dexamethasone sodium phosphate, and alveoloplasty with bone morphogenetic protein-2 (BMP-2). Conclusions. Few randomized controlled trials were found approaching cleft treatment, and fewer related to surgical repair of this deformity. So there is a need for more multicenter collaborations, mainly on surgical area, to reduce the variety of treatment modalities and to ensure that the cleft patient receives an evidence-based clinical practice.

Clinical and economic evidence for intravenous acetaminophen

Intravenous acetaminophen received United States Food and Drug Administration approval in November 2010 for the management of mild-to-moderate pain, management of moderate-to-severe pain with adjunctive opioid analgesics, and reduction of fever. Although intravenous acetaminophen generally improved pain relief and demonstrated opioid-sparing effects compared with placebo, it did not consistently reduce the frequency of opioid-related adverse events (e.g., postoperative nausea and vomiting). The safety and efficacy of intravenous acetaminophen as an antipyretic agent have been documented in adults and children; however, its cost is several-fold higher than that of the oral and rectal formulations. Although use of intravenous acetaminophen has reduced other postoperative resource utilization (e.g., hospital length of stay) in some studies outside the United States in patients undergoing abdominal surgery, a full economic evaluation in the United States has yet to be undertaken. In addition, its administration time (15-min infusion) and packaging (glass, single-use vial) have the potential to adversely affect patient flow in the postanesthesia care unit, create burden on patient care units, and lead to drug waste. Furthermore, 1 g of intravenous acetaminophen is formulated in 100 ml of solution, which may be an issue for patients with fluid restrictions. Given the clinical and economic evidence currently available, intravenous acetaminophen should not replace oral or rectal acetaminophen, but its use may be considered in a limited number of patients who cannot receive drugs orally and rectally and who cannot tolerate other parenteral nonopioid analgesic or antipyretic agents.

A randomized study of the efficacy and safety of intravenous acetaminophen compared to oral acetaminophen for the treatment of fever

OBJECTIVES

The purpose of this study was to assess the safety and dynamics of the onset of antipyretic efficacy of intravenous (IV) acetaminophen versus oral (PO) acetaminophen in the treatment of endotoxin-induced fever.

METHODS

This randomized, double-blind, double-dummy, single-dose study was conducted at a single center in the United States in healthy volunteer adult males with an endotoxin-induced fever to assess the antipyretic efficacy and safety of IV acetaminophen 1 g versus PO acetaminophen 1 g over 6 hours. Subjects who achieved a sufficient fever response to a test dose of reference standard endotoxin were randomly assigned to receive either IV acetaminophen and PO placebo (n = 54) or PO acetaminophen and IV placebo (n = 51). The primary efficacy outcome was the weighted sum of temperature differences from baseline at time T0 through T120 minutes. Safety evaluations included adverse event (AE), physical exam, and laboratory assessments.

RESULTS

Of 105 subjects receiving study medication, 24 vomited within 2 hours postdose (PO acetaminophen, n = 15; and IV acetaminophen, n = 9) and were excluded from the modified intent-to-treat population that consisted of 36 and 45 subjects treated with PO and IV acetaminophen, respectively. While this was done to not confer an advantage to the IV formulation, a sensitivity analysis including these subjects did not change the overall efficacy results. Statistically significant results favoring IV acetaminophen were observed for the primary endpoint (weighted sum of temperature differences over 120 minutes, p = 0.0039) and also at each time point from T30 to T90 minutes, although the maximum mean observed temperature difference was only 0.3°C. The study drugs were well tolerated. The AE frequency was comparable between the IV and PO groups.

CONCLUSIONS

A single dose of IV acetaminophen is as safe and effective in reducing endotoxin-induced fever as PO acetaminophen. IV acetaminophen may be useful where patients are unable to tolerate PO intake or when an earlier onset of action is desirable.

Fever and antipyretic use in children

Fever in a child is one of the most common clinical symptoms managed by pediatricians and other health care providers and a frequent cause of parental concern. Many parents administer antipyretics even when there is minimal or no fever, because they are concerned that the child must maintain a "normal" temperature. Fever, however, is not the primary illness but is a physiologic mechanism that has beneficial effects in fighting infection. There is no evidence that fever itself worsens the course of an illness or that it causes long-term neurologic complications. Thus, the primary goal of treating the febrile child should be to improve the child's overall comfort rather than focus on the normalization of body temperature. When counseling the parents or caregivers of a febrile child, the general well-being of the child, the importance of monitoring activity, observing for signs of serious illness, encouraging appropriate fluid intake, and the safe storage of antipyretics should be emphasized. Current evidence suggests that there is no substantial difference in the safety and effectiveness of acetaminophen and ibuprofen in the care of a generally healthy child with fever. There is evidence that combining these 2 products is more effective than the use of a single agent alone; however, there are concerns that combined treatment may be more complicated and contribute to the unsafe use of these drugs. Pediatricians should also promote patient safety by advocating for simplified formulations, dosing instructions, and dosing devices.

[Therapy of perioperative pain in pediatric urology]

Difficulties in estimating the kind and intensity of pain as well as uncertainty in drug selection and dosing are often responsible for a suboptimal treatment of pain therapy in the various age groups in childhood. The following article will help to minimize these deficits by contributing full details of safe and effective concepts for perioperative pain therapy in childhood.

Intravenous paracetamol: a review of efficacy and safety in therapeutic use

Paracetamol is well established as a leading nonprescription antipyretic analgesic drug and is available in oral, rectal or intravenous forms. However, except for oral paracetamol, there is a marked discrepancy between the extent to which paracetamol is used and the available evidence for an analgesic effect in postoperative pain. This review mainly focuses on intravenous paracetamol. Its efficacy and safety are analyzed, as well as its use in therapeutics, alone or in combination. The morphine-sparing, additive and antihyperalgesia effects of intravenous paracetamol are also reviewed. The analyses are divided into several sections, comparing the efficacy of intravenous paracetamol with placebo, other forms of paracetamol or analgesic agents and analyzing its efficacy in multimodal therapy combined with NSAIDs or a morphinic agent.

When to add supplemental rectal paracetamol for postoperative analgesia with caudal bupivacaine in children? A prospective, double-blind, randomized study

BACKGROUND

The aim of this study was to investigate whether a supplemental dose of rectal paracetamol at the third or fourth hour would enhance the quality of analgesia provided by caudal epidural blockade in children.

METHODS

Two hundred and two ASA I patients aged 1-12 years undergoing inguinal surgery were randomized into three groups in the postanesthesia care unit by drawing lots. Patients in the control group did not receive any analgesic until they had a pain score of 5 or higher, patients in the group P3 received rectal paracetamol (20-25 mg x kg(-1)) at the third hour, and patients in the group P4 received the same dose of rectal paracetamol at the fourth hour after caudal epidural injection. Pain was assessed by VAS (Visual Analog Scale) and supplementary rescue analgesic need was recorded.

RESULTS

There was no difference between the demographic data or the duration and variety of surgery among the groups. A significantly lower number of patients required rescue analgesia at the sixth postoperative hour in group P3 and also lower pain scores were again obtained in group P3 at the sixth and eighth postoperative hours.

CONCLUSIONS

Supplemental rectal paracetamol at the third hour of caudal blockade enhances the quality of postoperative analgesia better than its addition at the fourth hour in children undergoing inguinal surgery.

Paracetamol: new vistas of an old drug

Paracetamol (acetaminophen) is one of the most popular and widely used drugs for the treatment of pain and fever. It occupies a unique position among analgesic drugs. Unlike NSAIDs it is almost unanimously considered to have no antiinflammatory activity and does not produce gastrointestinal damage or untoward cardiorenal effects. Unlike opiates it is almost ineffective in intense pain and has no depressant effect on respiration. Although paracetamol has been used clinically for more than a century, its mode of action has been a mystery until about one year ago, when two independent groups (Zygmunt and colleagues and Bertolini and colleagues) produced experimental data unequivocally demonstrating that the analgesic effect of paracetamol is due to the indirect activation of cannabinoid CB(1) receptors. In brain and spinal cord, paracetamol, following deacetylation to its primary amine (p-aminophenol), is conjugated with arachidonic acid to form N-arachidonoylphenolamine, a compound already known (AM404) as an endogenous cannabinoid. The involved enzyme is fatty acid amide hydrolase. N-arachidonoylphenolamine is an agonist at TRPV1 receptors and an inhibitor of cellular anandamide uptake, which leads to increased levels of endogenous cannabinoids; moreover, it inhibits cyclooxygenases in the brain, albeit at concentrations that are probably not attainable with analgesic doses of paracetamol. CB(1) receptor antagonist, at a dose level that completely prevents the analgesic activity of a selective CB(1) receptor agonist, completely prevents the analgesic activity of paracetamol. Thus, paracetamol acts as a pro-drug, the active one being a cannabinoid. These findings finally explain the mechanism of action of paracetamol and the peculiarity of its effects, including the behavioral ones. Curiously, just when the first CB(1) agonists are being introduced for pain treatment, it comes out that an indirect cannabino-mimetic had been extensively used (and sometimes overused) for more than a century.

Rectal acetaminophen does not reduce morphine consumption after major surgery in young infants

BACKGROUND

The safety and value of acetaminophen (paracetamol) in addition to continuous morphine infusion has never been studied in newborns and young infants. We investigated the addition of acetaminophen to evaluate whether it decreased morphine consumption in this age group after major thoracic (non-cardiac) or abdominal surgery.

METHODS

A randomized controlled trial was performed in 71 patients given either acetaminophen 90-100 mg kg(-1) day(-1)or placebo rectally, in addition to a morphine loading dose of 100 microg kg(-1) and 5-10 microg kg(-1) h(-1) continuous infusion. Analgesic efficacy was assessed using Visual Analogue Scale (VAS) and COMFORT scores. Extra morphine was administered if VAS was > or = 4.

RESULTS

We analysed data of 54 patients, of whom 29 received acetaminophen and 25 received placebo. Median (25-75th percentile) age was 0 (0-2) months. Additional morphine bolus requirements and increases in continuous morphine infusion were similar in both groups (P = 0.366 and P = 0.06, respectively). There was no significant difference in total morphine consumption, respectively, 7.91 (6.59-14.02) and 7.19 (5.45-12.06) mug kg(-1) h(-1) for the acetaminophen and placebo group (P = 0.60). COMFORT [median (25-75th percentile) acetaminophen 10 (9-12) and placebo 11 (9-13)] and VAS [median (25-75th percentile) acetaminophen 0.0 (0.0-0.2) and placebo 0.0 (0.0-0.3)] scores did not differ between acetaminophen and placebo group (P = 0.06 and P = 0.73, respectively).

CONCLUSIONS

Acetaminophen, as an adjuvant to continuous morphine infusion, does not have an additional analgesic effect and should not be considered as standard of care in young infants, 0-2 months of age, after major thoracic (non-cardiac) or abdominal surgery.

Plasma concentrations following repeated rectal or intravenous administration of paracetamol after heart surgery

BACKGROUND

Paracetamol is commonly used for post-operative pain management in combination with more potent analgesics. The best route of paracetamol administration after major surgery, when oral intake may not be optimal, is not known. Our primary purpose was to study plasma concentrations after the 1st and 4th dose of 1 g of paracetamol given either rectally or intravenously (i.v.) after major surgery.

METHODS

In this prospective, randomized study, 48 patients undergoing heart surgery were randomized upon arrival to the intensive care unit (ICU) to receive paracetamol every 6th hour either as suppositories or intravenous injections. In half the patients (n = 24), blood samples for paracetamol concentration were obtained before and 20, 40 and 80 min after the first dose. In the other patients (n = 24), additional samples were taken prior to, and at 20, 40, 80 min and 4 and 6 h after, the 4th dose.

RESULTS

Plasma paracetamol concentration peaked (95 +/- 36 micromol/l) within 40 min after initial i.v. administration but did not increase within 80 min after the 1st suppository. Plasma concentration before the 4th dose was 74 +/- 51 and 50 +/- 27 in the rectal and i.v. groups, respectively. Paracetamol concentration peaked 20 min after the 4th dose for the i.v. patients (210 +/- 84 micromol/l) and declined to 99 +/- 27 micromol/l at 80 min as compared with the rectal patients 69 +/- 44 to 77 +/- 48 micromol/l.

CONCLUSION

Both time course and peak plasma concentrations of paracetamol given rectally differ from the one seen after intravenous administration. The clinical impact of these differences needs further investigation.

Analgesia and local anesthesia during invasive procedures in the neonate

BACKGROUND

Preterm and full-term neonates admitted to the neonatal intensive care unit or elsewhere in the hospital are routinely subjected to invasive procedures that can cause acute pain. Despite published data on the complex behavioral, physiologic, and biochemical responses of these neonates and the detrimental short- and long-term clinical outcomes of exposure to repetitive pain, clinical use of pain-control measures in neonates undergoing invasive procedures remains sporadic and suboptimal. As part of the Newborn Drug Development Initiative, the US Food and Drug Administration and the National Institute of Child Health and Human Development invited a group of international experts to form the Neonatal Pain Control Group to review the therapeutic options for pain management associated with the most commonly performed invasive procedures in neonates and to identify research priorities in this area.

OBJECTIVE

The goal of this article was to review and synthesize the published clinical evidence for the management of pain caused by invasive procedures in preterm and full-term neonates.

METHODS

Clinical studies examining various therapies for procedural pain in neonates were identified by searches of MEDLINE (1980-2004), the Cochrane Controlled Trials Register (The Cochrane Library, Issue 1, 2004), the reference lists of review articles, and personal files. The search terms included specific drug names, infant-newborn, infant-preterm, and pain, using the explode function for each key word. The English-language literature was reviewed, and case reports and small case series were discarded.

RESULTS

The most commonly performed invasive procedures in neonates included heel lancing, venipuncture, IV or arterial cannulation, chest tube placement, tracheal intubation or suctioning, lumbar puncture, circumcision, and SC or IM injection. Various drug classes were examined critically, including opioid analgesics, sedative/hypnotic drugs, nonsteroidal anti-inflammatory drugs and acetaminophen, injectable and topical local anesthetics, and sucrose. Research considerations related to each drug category were identified, potential obstacles to the systematic study of these drugs were discussed, and current gaps in knowledge were enumerated to define future research needs. Discussions relating to the optimal design for and ethical constraints on the study of neonatal pain will be published separately. Well-designed clinical trials investigating currently available and new therapies for acute pain in neonates will provide the scientific framework for effective pain management in neonates undergoing invasive procedures.

The Analgesic Efficacy of Acetaminophen, Ketoprofen, or Their Combination for Pediatric Surgical Patients Having Soft Tissue or Orthopedic Procedures

The combined use of acetaminophen and a nonsteroidal antiinflammatory drug has been shown to provide better postoperative analgesia than either drug alone in several adult studies. However, there are no pediatric studies analyzing similar effects when the currently recommended doses of acetaminophen are used. In a double-blind, placebo-controlled design we randomized 120 children, aged 1-9 yr, undergoing orthopedic or soft tissue surgery, into 3 groups to receive either acetaminophen 60 mg/kg rectally and 40 mg/kg orally, ketoprofen 2 mg/kg IV twice, or the combination of the active drugs. The first drug doses were given at anesthetic induction and the second doses 8 h thereafter. During anesthesia all children received sevoflurane and a continuous infusion of remifentanil. Postoperative pain was evaluated by the behavioral objective pain scale (0-9) for 24 h. The rescue medication was morphine 0.05 mg/kg IV. The primary outcome variable was morphine consumption. For statistical analysis, analysis of variance, chi2 test and Kaplan-Meier survival analysis were used. Morphine requirement was less in the combination than in the acetaminophen group both in the postanesthesia care unit (2.5 +/- 1.7 versus 3.9 +/- 2.1 morphine doses) and during the 24-h postoperative follow-up (4.1 +/- 2.5 versus 5.9 +/- 2.9 morphine doses) (P < 0.05). No differences existed between the ketoprofen and the acetaminophen groups. The objective pain scale scores were lowest in the combination group both in the postanesthesia care unit and in the postoperative ward (P < 0.05). When children were divided based on their surgery, opioid requirement and pain scores were less in the combination than in the parent drug groups only after orthopedic surgery. The combination of acetaminophen 100 mg/kg and ketoprofen 4 mg/kg in a day provided better analgesia and lower pain scores after orthopedic, but not soft tissue, surgery in children.

The pharmacokinetics of a single rectal dose of paracetamol (40 mg x kg(-1)) in children with liver disease

BACKGROUND

The aim of our study was to measure the serum paracetamol concentrations achieved following a single rectal loading dose of 40 mg x kg(-1) in children with chronic liver disease.

METHODS

We recruited 17 children (3-15 years, 10.6-75 kg) undergoing minor surgical procedures under general anesthesia. Paracetamol was administered at the end of surgery and blood samples were taken for analysis at 2, 3, 4, 6 and 8 h postdose.

RESULTS

The mean Cmax of 11.4 mg x l(-1) [coefficient of variation (CV) 66%] was achieved at a Tmax of 2.7 h (CV 42%). The relative bioavailability (F) of the suppository formulation was not estimated, but clearance (Cl/F) estimates 0.73 l x kg(-1) x h(-1) (CV 87%) and time-concentration profiles for these children were similar to the normal pediatric population.

CONCLUSIONS

There are currently no biologic markers available for monitoring possible hepatotoxicity in this cohort of patients with liver disease, but our data suggest that a single-dose suppository is a satisfactory analgesic alternative.

Pediatric acute pain management

Children are benefiting from the advances made in developmental neurobiology and analgesic pharmacology over the past few decades. Heightened public awareness and increased political pressure from external regulatory agencies are helping to maintain the momentum in improving pediatric pain management. As a result, methods of assessing and managing children's pain are being refined, and new modalities of pain relief are being explored. This review summarizes selected current topics in pediatric acute pain management, with the major emphasis on acute postoperative pain management.

Postoperative pain management: A practical review, part 1

PURPOSE

The pharmacotherapy and assessment of postoperative pain in general pharmacy practice settings are reviewed.

SUMMARY

Numerous factors related to all levels of society and the health care system contribute to suboptimal treatment of postoperative pain, despite awareness of this challenge for at least the past 30 years and the availability of potent analgesics and tools to help clinicians care for persons with postoperative pain. The consequences of acute pain include clinical, economic, and patient-reported outcomes; thus, improving the treatment of postoperative pain has the potential to improve health care from a broad perspective. Opioids remain the cornerstone of treatment of postoperative pain. Multimodal analgesia also has the potential to improve the pharmacotherapy of postoperative pain. In addition to the appropriate use of drugs, it is important that clinicians be comfortable with equianalgesic dosage conversion, helping ensure that analgesic-related adverse effects are minimal, assessing pain and function, and incorporating this information into patient care.

CONCLUSION

Providing optimal management of postoperative pain is a vital goal for all health care providers. There is substantial potential for pharmacists to help meet this goal.

Equal antipyretic effectiveness of oral and rectal acetaminophen: a randomized controlled trial [ISRCTN11886401]

BACKGROUND

The antipyretic effectiveness of rectal versus oral acetaminophen is not well established. This study is designed to compare the antipyretic effectiveness of two rectal acetaminophen doses (15 mg/kg) and (35 mg/kg), to the standard oral dose of 15 mg/kg.

METHODS

This is a randomized, double-dummy, double-blind study of 51 febrile children, receiving one of three regimens of a single acetaminophen dose: 15 mg/kg orally, 15 mg/kg rectally, or 35 mg/kg rectally. Rectal temperature was monitored at baseline and hourly for a total of six hours. The primary outcome of the study, time to maximum antipyresis, and the secondary outcome of time to temperature reduction by at least 1 degrees C were analyzed by one-way ANOVA. Two-way ANOVA with repeated measures over time was used to compare the secondary outcome: change in temperature from baseline at times 1, 2, 3, 4, 5, and 6 hours among the three groups. Intent-to-treat analysis was planned.

RESULTS

No significant differences were found among the three groups in the time to maximum antipyresis (overall mean = 3.6 hours; 95% CI: 3.2-4.0), time to fever reduction by 1 degrees C or the mean hourly temperature from baseline to 6 hours following dose administration. Hypothermia (temperature < 36.5 degrees C) occurred in 11(21.6%) subjects, with the highest proportion being in the rectal high-dose group.

CONCLUSION

Standard (15 mg/kg) oral, (15 mg/kg) rectal, and high-dose (35 mg/kg) rectal acetaminophen have similar antipyretic effectiveness.

Pain management for the hospitalized pediatric patient

Pediatric hospitalists should make pain assessment and treatment a high priority and a central part of their daily practice. Efforts at improving pain treatment in pediatric hospitals should be multidisciplinary and should involve combined use of pharmacologic and nonpharmacologic approaches. Although available information can permit effective treatment of pain for most children in hospitals, there is a need for more research on pediatric analgesic pharmacology, various nonpharmacologic treatments, and different models of delivery of care.

Postoperative Schmerztherapie nach Tonsillektomie im Kindesalter

OBJECTIVE

We investigated the efficacy and side-effects of a concept for pain therapy after tonsillectomy in children.

PATIENTS AND METHODS

A total of 100 children aged between 6 and 14 years were treated according to the following protocol for pain therapy after tonsillectomy: after induction of anaesthesia the children received 35-40 mg/kg acetaminophen rectally and 0.1 mg/kg piritramide i.v.. Additionally, boluses of 0.05 mg/kg pitritramide i.v. were allowed in the recovery room and 2 doses of 20 mg/kg acetaminophen were given rectally every 6 h on the day of surgery. On the following day the children received 30 mg/kg acetaminophen 3 times per day and from the second postoperative day onwards 1 mg/kg diclofenac was given 3 times a day. The rescue therapy was 5 mg/kg metamizol orally. The severity of the postoperative pain was evaluated by a visual pain scale (VAS) (0-100), side-effects such as vomiting and postoperative haemorrhage were documented. The Friedman test was used for testing the time course of pain intensity.

RESULTS

The median of the VAS was 42 on the day of surgery, 35 on the first postoperative day and fell continuously to 10 by the 6th postoperative day. The decrease of pain severity was statistically significant (p <0.05). A rescue therapy was necessary in 6 patients on the day of surgery and in 9 patients on the first postoperative day. 7 patients suffered a postoperative haemorrhage, 4 out of the 7 needed a surgical revision and 2 out of 100 patients vomited.

CONCLUSION

We conclude that this protocol for pain therapy after tonsillectomy was effective. The incidence of postoperative haemorrhage and vomiting was low.

Perioperative pharmacokinetics of ibuprofen enantiomers after rectal administration

BACKGROUND

Ibuprofen is a nonsteroidal anti-inflammatory drug which has both peripheral and central analgesic effects. Ibuprofen has been shown to be an effective antipyretic and postoperative analgesic drug both in adults and children with few side effects. Pharmacokinetics of rectal ibuprofen has not been studied, although suppositories are frequently used for perioperative pain control in children.

METHODS

There were four study groups: full-term infants aged 1-7 weeks (n = 9), infants aged 8-25 weeks (n = 8), and infants aged 26-52 weeks (n = 7). Adult patients were 20-40 years old (n = 7). Ibuprofen suppository 20 mg.kg(-1) was administered after induction of anesthesia. Blood samples were collected from 20 min to 10 h after dosing and pharmacokinetic analysis of ibuprofen enantiomers were done.

RESULTS

Both ibuprofen enantiomers were detectable in blood in 20 min. Total ibuprofen plasma concentrations >10 mg.l(-1) were seen from 40 min to 8 h. Values for T(max) of ibuprofen enantiomers and total ibuprofen were higher in the adult group than any of the infant groups (P < 0.05). In addition, values for physiological (standardized) t(1/2) of (R)-(-)- and (S)-(+)-ibuprofen were higher in infants aged 1-7 weeks than the adults (P < 0.05). None of the other pharmacokinetic variables, C(max), AUC, chronological t(1/2) or AUC ratio differed between the groups.

CONCLUSIONS

A single dose of ibuprofen suppository 20 mg.kg(-1) after induction of anesthesia guarantees analgesic plasma concentrations during the early postoperative period. Except for the delayed absorption of ibuprofen in adults and higher physiological t(1/2) in infants aged 1-7 weeks, no major pharmacokinetic differences were observed between study groups.

Accuracy in the alteration of acetaminophen suppositories

Many pediatric anesthesiologists divide acetaminophen suppositories to achieve an approximate dose. In this three-part study we first surveyed pediatric anesthesiologists regarding their attitudes and frequency of this clinical practice. Second, acetaminophen suppositories were divided for analysis of acetaminophen content. Finally, the accuracy of pediatric anesthesiologists in dividing suppositories was assessed. The survey indicated 50% of anesthesiologists believed acetaminophen was nonuniform and 62% believed the alteration of suppositories was inaccurate. The laboratory investigation revealed uniform distribution of acetaminophen but poor accuracy in achieving the target dose. The findings suggest using only intact suppositories for improved accuracy.

Single High-Dose Rectal Acetaminophen in Children

OBJECTIVE

To determine whether there is sufficient evidence to support the use of one-time high-dose (>30 mg/kg) rectally administered acetaminophen to control postoperative pain in children.

DATA SOURCES

Literature was accessed through MEDLINE (1966–May 2004) and bibliographic searches.

STUDY SELECTION AND DATA EXTRACTION

All articles identified from the data sources were evaluated and all studies regarding the use of greater than 30 mg/kg of acetaminophen in children were included for this review.

DATA SYNTHESIS

A single high dose of rectally administered acetaminophen has been used in children to control postoperative pain. Ten randomized controlled trials and pharmacokinetic studies evaluating the use of greater than 30 mg/kg of rectally administered acetaminophen in children were identified and reviewed. Each study had a unique objective. The studies also differed substantially in regard to design, study population, dosing, rectal formulation used, and monitoring.

CONCLUSIONS

Due to limited study data, wide study variability, and lack of standardization in terms of design, objectives, study population, dosing, rectal formulation, and monitoring, compounded by the fact that children often require additional doses of acetaminophen to control postoperative pain, the practice of using one-time, high-dose, rectally administered acetaminophen in children cannot be recommended at this time.

Evaluation of adding preoperative or postoperative rectal paracetamol to caudal bupivacaine for postoperative analgesia in children

BACKGROUND

Our aim was to investigate whether effects of caudal analgesia could be extended by preoperative or postoperative rectal paracetamol administration in children undergoing surgical repair of hypospadias.

METHODS

The group consisted of 60 ASA I boys, aged 3-12 years, who were operated for surgical repair of hypospadias. The patients were randomized into three groups: patients in group I received rectal paracetamol (20-25 mg x kg(-1)) just before the operation. Group II received only caudal bupivacaine. Group III patients received rectal paracetamol (20-25 mg x kg(-1)) at the end of the operation. Pain was assessed by Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) and the degree of sedation was evaluated. During the first 24 h, time to the patients' first analgesic requirement and the number of supplementary analgesics needed were recorded.

RESULTS

There was no difference between the demographic and haemodynamic data of the three groups. In addition, the duration of surgery and anaesthesia, pain scores and sedation scores of the groups were not significantly different.

CONCLUSIONS

Addition of preoperative or postoperative rectal paracetamol in the doses used did not show an effect on the duration and intensity of postoperative analgesia obtained by caudal bupivacaine.