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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

Several investigators have documented immaturity of cardiac autonomic innervation in neonates. To evaluate the integrity of afferent and efferent responses and to determine the role of circulating catecholamines in newborns, 50 puppies and 24 adult dogswere studied with the use of chloralose anesthesia. Interventions were: bilateralvagotomy, bilateral carotid occlusion, central vagus stimulation, stellate stimulation, bilateral adrenalectomy, infusion of norepinephrine or isoproterenol, and intravenoustyramine. Newborns exhibited supersensitivity to exogenous norepinephrine, isoproterenol, and stellate stimulation; responses to carotid occlusion and central vagal stimulation were comparable in both groups. Newborns had less resting vagal tone. After adrenalectomy, newborns exhibited a more marked decline in systemic pressureand heart compared to adults. Myocardial catecholamine content in newborns was 1/10 that in adults, whereas plasma catecholamine concentration in newborns was 30-fold greater than in adults. These data demonstrate functional integrity of afferent and efferent cardiac autonomic pathways in the newborn, define in vivo supersensitivity to the sympathetic neurotransmitter, and suggest a dominant role of circulating catecholamines in modulation of cardiovascular events in neonates.
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PMID:Factors influencing neurohumoral control of the heart in the newborn dog. 115

The physiologic immaturity of respiratory musculature and central respiratory control centers leads to an increased risk of apnea and respiratory complications following general anesthesia in the neonate. Regional anesthetic techniques, such as spinal and caudal epidural anesthesia, may obviate the need for general anesthesia and lessen the risks of perioperative morbidity. Although these techniques have been previously described in infants, most reports focus on regional anesthesia in the former preterm infant outside the actual neonatal period. There is relatively little or no information concerning regional anesthesia in neonates during the first week of life. We present four neonates (weight, 1.07 to 2.8 kg; gestational age, 27 to 35 weeks) who required anesthetic care during the first week of life for various surgical procedures, including vesicostomy placement, gastroschisis closure, and debridement of a lower-extremity wound. Either caudal epidural or spinal anesthesia was successfully used in the four neonates. Regional anesthesia was used as the sole technique without supplementation with intravenous or inhalational agents in three of the four neonates. The advantages, risks, and applications of regional anesthesia in the neonate are discussed.
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PMID:Regional anesthesia in the preterm neonate. 142 95

On the basis of rich clinical experience--593 patients and 916 renoureteral units (RUU) with vesicoureteral reflux (VUR) in infants the authors showed that early recognition of VUR is necessary, which is ensured by adequate organization of service to infants of the "risk group". Complex examination of children by functional diagnostic methods conducted under general anesthesia makes it possible to undertake some methods of examination for the detection and control of morphofunctional immaturity, while early application of purposeful rehabilitation measures in the stages inpatient treatment--outpatient treatment--treatment in the family produces a "positive dynamics" of the course of the pathological process in most patients (up to 82.1%). All this in complex confirms that morphofunctional immaturity of the urinary tract is the main cause of VUR in infants.
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PMID:[Morphofunctional immaturity of the urinary tract and vesicoureteral reflux in young children]. 194 85

The greater survival of premature infants, the frequency with which these children present a pathology of surgical treatment, and their physiological immaturity, particularly in the respiratory system, entail a great many difficulties in the postoperative process. With the aim of decreasing these postoperative difficulties and because of the publications of several articles with the same goal, it is implemented a study of spinal anesthesia with isobaric bupivacaine in the premature babies put under a treatment or surgery of the inguinal canal, in order to asses the efficiency of this technique and the cardiovascular consequences. The average duration of the anesthesia was 59 +/- 13 minutes. The latency period is practically nonexistent and the average level that was achieved is situated between D4-D6, which is enough so as to carry out the operation without problems and achieving a complete analgesia in the inguinal area. It has not been observed relevant hemodynamic alterations. The outcomes are obvious, for the difficulties disappear, especially those coming from the respiratory system in the general anesthesia with intubation such as apnea, cyanosis and bradycardia, stridor and atelectasis. This kind of anesthesia allows the surgeon a perfect relaxation and analgesia and the children a comfort throughout the surgical event. By way of conclusion, the spinal anesthesia is a good option instead of the general anesthesia for suckling babies because of the risk of respiratory difficulties they present, alone all when they are premature and they are recovering from a syndrome of respiratory difficulty.
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PMID:[Intradural anesthesia: an alternative in surgery on premature infants]. 207 65

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

The authors present the protocol currently used in their institution for initial and follow-up evaluation of infants at high risk for developing retinopathy of prematurity (ROP). After topical anesthesia and lid speculum insertion, the examination is carried out using an indirect binocular ophthalmoscope with a +20 or +28-diopter lens. Mydriasis is achieved by instilling one drop of 1% tropicamide, followed by one drop of 0.5% tropicamide + 2.5% phenylephrine 15 minutes later and after an additional 15 minute interval, another drop of 1% tropicamide. If mydriasis is insufficient after one hour, one drop of a 0.5% tropicamide-5.0% phenylephrine solution may be instilled. The initial examination is performed between the third and fourth weeks of life. If any areas of retinal immaturity are found, the examination is repeated every other week and, later, every three to four weeks, until vascularization has reached the ora serrata. Should any sign of ROP be present during the first examination, the patient is examined weekly or every other week depending on the severity of clinical findings.
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PMID:Retinopathy of prematurity (ROP): optimal timing of clinical evaluation and standard procedures. 220 81

Artificial respiration is often indicated in the child surgical patient preoperatively, as well as postoperatively because of the specific features of this age group. The characteristics of the respiratory function which are various in different ages, as well as the preoperative condition of the child and the nature of the surgical procedure and anaesthesia are factors which influence the indications for artificial respiration. Of particular importance is the neonatal period of the child where beside the immaturity of vital functions, and a high metabolism level with small calorie reserves, as well as a large consumption of oxygen, there is the addition of stress due to the surgical procedure and anaesthesia which can seriously endanger respiration. The paper analyzes indications for applying artificial respiration at the Clinic for Child Surgery in Novi Sad during a five-year period. Ways of applying artificial respiration, its parameters, as well as the complications during its use are followed. Artificial respiration was applied in 82 children, 46.34% were newborns operated on because of ileus conditions and 43.90% were larger children treated due to polytrauma. The most frequent complications were in the group of newborns: pneumonia, atelectasis, ductus arteriosus opening, lung bleeding and pneumothorax.
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PMID:[Indications for use of artificial ventilation and its complications in pediatric surgery]. 228 7

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

The use of extracorporeal shock wave lithotripsy (ESWL) in the management of ten patients with complex biliary tract stones is described. General or epidural anesthesia was used in all cases, and stone fragmentation was performed, using an unmodified Dornier HM3 waterbath lithotripter (Dornier Medical Systems Inc., Marietta, GA). In all cases, biliary drainage was established before the procedure to allow contrast visualization during and after the procedure, as well as to ensure free drainage of the common bile duct. Indications for ESWL included failure of basket extraction (4 cases), unfavorable anatomy (duodenal diverticulum, previous Billroth II reconstruction, hepatic duct stone, gallbladder stone, cystic duct remnant stone), and immaturity of the T-tube tract (2 cases). Cholangitis was the presenting diagnosis in four cases. Fragmentation of the stones was successful in all patients; in two cases, two ESWL sessions were needed for stone disruption. Morbidity was minimal (there was a minor elevation of LDH and transaminases and asymptomatic hemobilia and hematuria); pancreatitis did not occur. After ESWL, hospital stays ranged from 1 to 13 days (mean of 5.3 days). ESWL can be a valuable adjunct in the management of patients with complex biliary stones.
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PMID:Extracorporeal shock wave lithotripsy (ESWL) in the management of complex biliary tract stone disease. 319 Feb 85


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