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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The introduction of the new long acting local anaesthetics, bupivacaine and etidocaine, has stimulated an expansion of interest in regional anaesthesia, particularly for obstetrical applications and pain therapy. System toxicity following injection of local anesthetics occurs albeit infrequently, and tentative correlations have been made between the onset of CNS and cardiovascular effects and circulating drug concentrations in both adults and neonates. Amongst other factors, interpretation of these relationships depends upon blood distribution and plasma binding of the agents, sampling sites and acid-base balance. The disposition kinetics and placental transfer of the amide type agents have been well characterised. In adults their clearance is almost entirely hepatic but in neonates an increase in the renal component is, in part, a reflection of the immaturity of some of the enzymes responsible for their metabolism. Ester type agents are rapidly hydrolysed by plasma pseudocholinesterase and this has led to a preference for chloroprocaine in some obstetric procedures. Major determinants of the systemic absorption of the agents after perineural administration include their physicochemical and vasoactive properties, perfusion and tissue binding at the site of injection and whether or not adrenaline has been added. In respect of blood drug concentrations achieved after various regional anaesthetic procedures, the margin of systemic safety appears to favour bupivacaine and etidocaine compared to shorter acting analogues such as lignocaine and mepivacaine. The time course of local anaesthetic remaining at the site of injection has been calculated following intravenous regional anaesthesia and peridural block. This has allowed prediction of the local and systemic accumulation of the drugs following contined dosage. Blood concentrations of local anaesthetics after perineural injection are not closely related to age, weight or pregnancy but may be influenced by diseases associated with haemodynamic changes and by other drugs given at or around the time of regional blockade.
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PMID:Clinical pharmacokinetics of local anaesthetics. 38 8

Total hip or knee arthroplasty is indicated in patients with juvenile rheumatoid arthritis when there is marked functional impairment and/or severe disabling pain from advanced structural hip or knee joint involvement. Relief of pain and dramatic improvement in function can be achieved in most patients. When both the hip and knee are involved, hip arthroplasty should probably be done first. Regional anesthesia is preferable. Careful preoperative planning is essential because custom prostheses are often required. Small bone size, osteoporosis, and soft-tissue contractures make the surgery technically demanding. Skeletal immaturity is not an absolute contraindication to surgery. Component loosening is the most frequent late complication in hip arthroplasty. It is less common in condylar metal-to-plastic knee arthroplasty in which patellar complications predominate. Cementless arthroplasty has an evolving role in the patient with juvenile rheumatoid arthritis and, to date, is more often used in the hip than in the knee.
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PMID:Total hip and knee arthroplasty in juvenile rheumatoid arthritis. 220 78

After having been virtually completely forgotten since the Second World War, paediatric regional anaesthesia has been undergoing a renewal in the last decade. This renewed interest in old techniques is due to several converging factors: a better knowledge of the pharmacology of local anaesthetic agents in the child, the availability of equipment adapted for children, the remarkable haemodynamic stability of the very young child during an epidural block, as well as the need to treat pain not just in the operative period. The child is not, or rather, is not only a small adult. Embryological development is not finished at birth. The incompletely myelinized nervous system as well as the incomplete skeletal ossification will influence local anaesthetic pharmacodynamics and the choice of anaesthetic technique and anatomical landmarks. Aponeurotic sheaths are only poorly attached to anatomical structures, especially nerves. This, together with the fact that epidural fat in the young child is very fluid, explains why some techniques are very efficient, but also why the volumes of required anaesthetic solution are proportionately much more important than in adults. The general pharmacology of local anaesthetic drugs is very close to adults. However, the very important regional blood flow rates, the different body water distribution, the immature neurovegetative system, the weak activity of some enzymes, and the relatively greater importance of the liver and brain by weight explain the differences found in pharmacokinetics, which are differences in degree and not in nature. The choice of the appropriate local anaesthetic agent depends on these factors. In France, the chosen drug will almost exclusively be an amide, mostly lignocaine and bupivacaine. The psychological immaturity of children makes any assessment of pain quite difficult. Moreover, body image has not yet been completely acquired in most cases, so reducing the possibility of conceptualization. The usefulness of techniques requiring an active patient participation, in particular the search for paraesthesia, is therefore rather reduced. Light general anaesthesia and peripheral nerve stimulators (for nerve blocks) are essential, and desirable at least, if not wished by most patients. Caudal anaesthesia is an important technique in the child. It is easy to perform, efficient, with small risk. Its ideal indication is surgery below the umbilicus in the infant and young child. Lumbar epidural anaesthesia requires greater experience as well as proper equipment, especially in the very young child. Peripheral nerve blocks are less used than in adults.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Regional anesthesia in pediatrics]. 265 20

From 1971 to 1981, total knee arthroplasty was performed on forty-eight knees in twenty-eight patients with juvenile rheumatoid arthritis at the Robert Breck Brigham (now Brigham and Women's) Hospital. Seventeen of these patients, with twenty-nine knee-replacement arthroplasties, were followed for from two to eleven years (average, five years) and are the basis for this study. The patients' ages at operation ranged from thirteen to thirty-nine years (average, twenty-three years). Six patients had undergone total hip arthroplasty prior to admission for total knee replacement, and five patients had a total hip replacement performed while they were hospitalized for the knee arthroplasty. Thirteen patients (twenty-one knees) had significant preoperative pain but only three (five knees) had severe discomfort. Four patients were unable to walk, three were household walkers, and ten were limited community walkers. Preoperative deformities of the knees ranged from 20 degrees of varus angulation to 35 degrees of valgus angulation. The average preoperative flexion deformity was 23 degrees and the arc of motion averaged 45 degrees. At follow-up, twenty of the twenty-one knees that had been significantly painful preoperatively were completely relieved of discomfort. The average arc of motion increased by 34 degrees, while in all but one knee the angular deformity had been corrected to zero to 10 degrees of valgus angulation. All but one patient became a limited or full community walker. Complications included one late deep infection and one posterior tibial subluxation. Four knees required subsequent resurfacing of the patella for treatment of pain. We now routinely resurface the patella in all patients with juvenile rheumatoid arthritis who have a total knee replacement. To date no prosthesis has required revision for loosening. Radiolucency of one millimeter or less about the prosthesis was noted at follow-up in eight (30 per cent) of the knees. As custom-made components were required in twelve of the twenty-nine knees, it is obvious that preoperative planning is crucial in the treatment of these patients. Our recent experience has shown that the use of preoperative and postoperative serial casts aids greatly in the correction of severe flexion deformity of the knee. Postoperative manipulation was required for twenty-one of the twenty-nine knees. Skeletal immaturity was not an absolute contraindication to surgery. We think that our results, which showed a marked improvement in both knee function and in quality of life, make the short and long-term risks of knee-implant surgery well worth taking in this patient population.
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PMID:Total knee arthroplasty in juvenile rheumatoid arthritis. 663 Feb 51

Total hip arthroplasty (THA) or total knee arthroplasty (TKA) is indicated for patients with juvenile rheumatoid arthritis (JRA) when marked joint destruction is present and pain or deformity compromises function despite optimal medical therapy. Relief of pain, reduction of the deformity, and dramatic improvement in functional status and quality of life can be achieved in most patients. Functional impairment and deformity rather than pain are usually the primary indications for THA or TKA. When there is both hip and knee involvement, hip arthroplasty should probably be done first. Regional anesthetic appears to be the anesthetic of choice. Careful preoperative planning and the availability of custom and minisized components are essential. Small bone size, osteoporosis, and severe soft tissue disease make the surgery technically demanding. Skeletal immaturity may not contraindicate surgery if the patient is otherwise bedridden with progressive deformity. In the hip trochanteric osteotomy is often necessary for adequate exposure, with the possible exception being a patient with juvenile ankylosing spondylitis who is subject to heterotopic bone formation. Although complete capsulectomy and psoas tenotomy may be necessary to relieve a hip flexion contracture, a soft tissue release that produces leg lengthening may lead to nerve palsy. In the hip component loosening has been less common in patients with JRA than in other young patients who have undergone THA, but it is still the most frequent cause of failure. In the knee preoperative and postoperative serial casts can aid in the correction of severe flexion contracture. Secondary patellar pain has been the most common cause of late failure. Patellar resurfacing should probably be performed at the time of the original knee arthroplasty in all patients with JRA.
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PMID:Total hip and total knee arthroplasty in juvenile rheumatoid arthritis. 669 30

Whether meperidine metabolism is affected by pregnancy or immaturity has not been clearly established. This is of interest because meperidine is commonly given during labor for pain relief and the fetus receives the drug in utero. Moreover, animals studies suggest that the hormones of pregnancy contribute to decreased activity of the drug-metabolizing enzymes. In our study gas chromatography was used to determine the concentrations of meperidine and normeperidine in the plasma and urine of pregnant and nonpregnant women and in the urine of neonates. Plasma samples were collected for at least 3 hr after a dose of meperidine intravenously to calculate the kinetic parameters of meperidine disposition; urine samples were collected for 3 days. In contrasts to reports on animals, we found that pregnant and nonpregnant women readily metabolize meperidine to normeperidine and excrete both in a similar manner. No significant differences were demonstrated between any of the kinetic constants for peripartum and nonpregnant subjects. The neonate was found to metabolize and excrete these drugs less rapidly.
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PMID:Meperidine disposition in mother, neonate, and nonpregnant females. 735 7

A cecoileal reflux detected in children under the age of 5 years may be related to the manifestations of relative immaturity. In older children experiencing continuous pain, irrigography must be performed to verify the diagnosis and the degree of the reflux. In a group of 111 patients, 51 with Degree 2 and 3 passive reflux underwent operation. Appendectomy was performed in which the purse-string suture created conditions for tightening the frenuli, which explains the effectiveness of interventions verified by late results.
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PMID:[Diagnosis and treatment of ceco-ileal reflux in children]. 767 32

Apophyseal injuries, which are unique in the adolescent athlete, cause inflammation at the site of a major tendinous insertion onto a growing bony prominence. These injuries typically occur in active adolescents between the ages of eight and 15 years and usually present as periarticular pain associated with growth, skeletal immaturity, repetitive microtrauma and muscle-tendon imbalance. Common apophyseal injuries, and their sites, include Sever's disease (posterior calcaneus), Osgood-Schlatter disease (tibial tuberosity), Sindig-Larsen-Johansson syndrome (inferior patella), medial epicondylitis (humeral medial epicondyle) and apophysitis of the hip (iliac crest, ischial tuberosity). Conservative therapy, including rest, ice, compression, elevation, nonsteroidal anti-inflammatory agents, modification of the athlete's activity level and exercises for increased flexibility and strengthening, is usually effective.
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PMID:Apophyseal injuries in the young athlete. 776 80

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.
J Pain Symptom Manage 1993 Jan
PMID:Neonatal pain: a comprehensive survey of attitudes and practices. 848 95

Important differences become evident in a comparison of cancer pain between children and adults. Management of pain in children is commonly multidisciplinary, is less dependent on invasive measures and relies more on systemic therapy. Children are not little adults: their immaturity, developing cognition and dependence all influence their experience and interpretation of pain. Much progress has been made in altering practices such as under-prescribing and underdosing that have adversely affected adequate control of pain in children. The challenge for paediatric health care providers in the mid 1990s is not only to be informed of current practices in pain and symptom control in paediatric palliative care, but also to remember to establish those practices in day to day management. Even though pain and its effects in children are now better understood, it is often still not managed optimally. Good management of pain in children depends on accurate assessment. In the past 10 years, assessment of pain in children has advanced considerably. However, assessment of pain in the preverbal child is still inadequate and in need of attention. Sedation, tolerance and involuntary movements may occur as side effects of opioids in children and may cause significant problems in management of the dying child. Psychostimulants can diminish sedation to some extent, but there is little information as yet on the value of these drugs in children. Tolerance to opioids may develop quickly, leading to poor control of pain and distress for the child. Strategies to improve management of tolerance include use of regional anaesthetic techniques such as the epidural/intrathecal route for opioid administration. Involuntary movements induced by opioids are uncommon but have the potential to cause significant distress. The mechanisms underlying these side effects of opioids need to be established. Strategies are needed for the effective treatment and prevention of these side effects. Neuropathic pain can be severe, distressing and difficult to treat. Experience of its treatment in terminally ill children is limited. Effective use of tricyclic antidepressants and systemically administered local anaesthetics is still to be determined. Regional anaesthetic techniques may be of great benefit when neuropathic pain cannot be controlled with systemic therapy. Procedural pain is more common than pain related to disease in the management of paediatric cancer. Further research is needed to identify the best approach to its management. We have found nitrous oxide to be of great benefit in management of procedural pain in children. Non-pharmacological methods of treatment of pain in children, such as transcutaneous electrical nerve stimulation or acupuncture, may also be useful and should receive continuing evaluation. There are significant and current issues in paediatric palliative care besides management of pain. There are difficulties in the provision of home nursing care for children with cancer in the terminal phase of their illness, including lack of community nursing services at night and on weekends and lack of adequate home help for parents. Attitudes of staff involved in the care of the child and family and their commitment to working as a multidisciplinary team strongly influence the quality and success of care given. Pain control and palliative medicine are evaluable by measures of quality assurance or outcome, and adoption of such evaluations should improve standards of care. Euthanasia in children is even more difficult as an ethical dilemma than in adults. Optimum symptom control with current techniques should almost always obviate its consideration. We are opposed to euthanasia. Psychosocial and cultural issues all influence the family's experience of palliative care. Further research is necessary in all of these areas.(ABSTRACT TRUNCATED)
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PMID:Pain and symptom control in paediatric palliative care. 856 95


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