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Su F, Gastonguay MR, Nicolson SC, DiLiberto M, Ocampo-Pelland A, Zuppa AF. Dexmedetomidine Pharmacology in Neonates and Infants After Open Heart Surgery. Anesth Analg 2016. [DOI: 10.1213/ane.0000000000000869] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
The structural defects associated with the various forms of congenital heart disease lead to pathological and functional changes that place patients at risk for adverse events, and in fact the perioperative incidence of morbidity and mortality has been documented to be increased in children with congenital heart disease. Patients with congenital heart disease can present to the anesthesiologist in a relatively precarious state of balance of several hemodynamic factors, including preload, ventricular contractility, systemic vascular resistance, pulmonary vascular resistance, heart rate, and cardiac rhythm. Anesthetic drugs can affect each of these, and an ideal anesthetic drug for such patients does not exist. The purpose of this article is to review the hemodynamic effects of anesthetic drugs and how they may contribute to the occurrence of adverse events in children with congenital heart disease.
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Affiliation(s)
- Robert H. Friesen
- Children’s Hospital Colorado, University of Colorado School of Medicine, Aurora, CO, USA
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Gulur P, El Saleeby C, Watt LD, Koury KM, Cohen AR. Elevated lidocaine serum levels following the use of a needle free device in healthy adult volunteers. Pediatr Emerg Care 2014; 30:335-9. [PMID: 24786988 DOI: 10.1097/pec.0000000000000125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
There is increased concern regarding circulating levels of lidocaine immediately after the use of a needle-free device with buffered lidocaine. As a result, we conducted a prospective study to assess lidocaine circulation after the use of a needle-free device for the delivery of a local anesthetic in 10 healthy adult subjects. After informed consent, 2 peripheral intravenous catheters were placed in the antecubital fossa of each arm. Two milligrams of 1% buffered lidocaine was administered by the study physician via the needle-free device on the dorsum of the subject's hand. Within 2 minutes, a third intravenous catheter was placed in the location of the lidocaine administration and 5 mL of blood was collected from all 3 sites. If blood samples returned positive for lidocaine, they were also collected 1 hour and 2 hours after administration. Toxic levels of lidocaine were found in blood drawn from 2 subjects immediately after lidocaine administration. Results also showed that certain subjects had increasing levels of lidocaine over time. Other subjects also had increasing lidocaine serum levels from blood drawn on the arm opposite the administration site. We concluded that there may be systemic lidocaine levels with the administration of the needle-free device and that these levels may reach the toxic range in adults. Further investigation will be required to determine whether this finding has clinical significance, especially considering the smaller body mass of children.
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Affiliation(s)
- Padma Gulur
- From the *Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital; †Harvard Medical School; Departments of ‡Emergency Medicine, and §Pediatrics, Massachusetts General Hospital, Boston, MA
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Developing and Optimizing a Chronic Cyanotic Swine Model. J Surg Res 2011; 171:170-4. [DOI: 10.1016/j.jss.2010.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Revised: 02/12/2010] [Accepted: 03/01/2010] [Indexed: 11/22/2022]
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Dyck JB, Wallace MS, Lu JQ, Rossi SS, Yaksh TL. The pharmacokinetics of lignocaine in humans during a computer-controlled infusion. Eur J Pain 2004; 1:141-8. [PMID: 15102415 DOI: 10.1016/s1090-3801(97)90072-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/1997] [Accepted: 07/11/1997] [Indexed: 11/21/2022]
Abstract
Several types of chronic pain syndromes are effectively treated with sodium channel blockers such as lignocaine. Further investigation of this therapeutic modality would be facilitated by refinement of the parameters describing lignocaine distribution and elimination. This would allow precise lignocaine infusion by a computer-controlled infusion to attain and maintain stable target lignocaine concentrations. Arterial blood samples were obtained at frequent intervals during a computer-controlled infusion of lignocaine in 12 adult human volunteers. Plasma lignocaine concentrations of 1, 2, 3, 4 and 5 microg/ml were targeted for 15 min at each concentration. A three-compartment mammillary pharmacokinetic model best described the resulting concentration vs time profile. A population pharmacokinetic analysis was performed using three different techniques; the two-stage, pooled and mixed effects modelling. There was marked overshoot of the plasma concentration above the target prior to refinement of the pharmacokinetic parameters. The best parameters of a three-compartment mammillary model fit to the measured concentration using the pooled data approach were: V(1) = 7.44, V(2) =11.5 and V(3) = 97.71; Cl(1) = 0.585, Cl(2) = 2.23 and Cl(3) =1.64 l/min. Similarly calculated parameters using NONMEM were V(1) = 6.99, V(2) =12.2 and V(3) =1341; Cl(1) = 0.703, Cl(2) =1.24 and Cl(3) =1.49 l/min. The addition of age as a covariate of the pharmacokinetic parameters improved the model in both cases. Height, lean body mass and body surface area as covariates of the pharmacokinetic parameters did not improve the predicted value of the model. Prospective testing of the pharmacokinetic parameters will be required to define whether they function well. The refinement of pharmacokinetic parameters for the computer-controlled intravenous infusion of lignocaine will facilitate further research in pain therapy. Published lignocaine pharmacokinetic values have a relatively large central volume of distribution, and hence, when implemented as a computer-controlled infusion, result in dramatic overshoot shortly after targeting a higher plasma concentration. In light of the long-lasting pain relief provided by sodium channel blockade in neuropathic pain states, overshoot of plasma concentrations must be avoided if the concentration vs effect relationship is to be defined.
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Affiliation(s)
- J B Dyck
- Department of Anesthesiology, VA Medical Center and UCSD School of Medicine, San Diego, California 92103, USA
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Affiliation(s)
- F Boer
- Department of Anaesthesiology, P5-Q, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
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Gozal Y, Mints B, Drenger B. Time course of neuromuscular blockade with rocuronium in children with intracardiac shunts. J Cardiothorac Vasc Anesth 2002; 16:737-8. [PMID: 12486656 DOI: 10.1053/jcan.2002.128409] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To evaluate the time course of neuromuscular blockade after rocuronium in children with intracardiac shunts. DESIGN Prospective study. SETTING University hospital. PARTICIPANTS Consecutive children (n = 52) with intracardiac shunts scheduled for elective cardiac surgery. Participants were allocated to 2 groups according to the direction of the shunt. INTERVENTIONS Rocuronium, 0.6 mg/kg, was administered for muscle relaxation. The ulnar nerve was stimulated at 20-second intervals with a supramaximal 2-Hz train-of-4 stimulation (TOF-Guard nerve stimulator; Biomet International, Odense, Denmark). The onset time to maximal twitch depression and the time to clinical recovery were compared between the 2 groups. MEASUREMENTS AND MAIN RESULTS The time to maximal block was significantly faster in children with a right-to-left shunt: 56.8 +/- 5.3 seconds versus 77.1 +/- 6.6 seconds (p = 0.01). There was a tendency to shorter recovery in children with a right-to-left shunt: 42.3 +/- 6.1 minutes versus 55.4 +/- 4.9 minutes (p = NS). CONCLUSION This study shows a more rapid onset of rocuronium in children with cyanotic congenital heart disease. In these patients, rocuronium is indicated, particularly for rapid airway control.
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Affiliation(s)
- Yaacov Gozal
- Department of Anesthesiology and Critical Care Medicine, Hadassah University Hospital, Jerusalem, Israel.
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Affiliation(s)
- Brian J Anderson
- Department of Anaesthesia, Auckland Children's Hospital, Auckland, New Zealand
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Anderson B, Chojnowska E. Pharmacokinetics and the drugs used in pediatric regional anesthesia. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s1084-208x(99)80033-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nunes de Moraes A, Dyson DH, O'Grady MR, McDonell WN, Holmberg DL. Plasma concentrations and cardiovascular influence of lidocaine infusions during isoflurane anesthesia in healthy dogs and dogs with subaortic stenosis. Vet Surg 1998; 27:486-97. [PMID: 9749521 DOI: 10.1111/j.1532-950x.1998.tb00161.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To determine the plasma concentrations and cardiovascular changes that occur in healthy dogs and dogs with aortic stenosis that are given an infusion of lidocaine during isoflurane anesthesia. STUDY DESIGN Phase 1, controlled randomized cross-over trial; Phase 2, before and after trial ANIMALS Phase 1, 6 healthy dogs (4 female, 2 male) weighing 23.8 +/- 7.4 kg; Phase 2, 7 dogs (4 female, 3 male) with moderate to severe subaortic stenosis (confirmed by Doppler echocardiography) weighing 31.1 +/- 14.5 kg. METHODS After mask induction, intubation, and institution of positive pressure ventilation, instrumentation was performed to measure hemodynamic variables. After baseline, measurement at an end-tidal isoflurane concentration of 1.9% (phase 1) or 1.85% (phase 2), a loading dose infusion of lidocaine at 400 microg/kg/min was given. Phase 1: Maintenance doses of lidocaine were administered consecutively (40, 120, and 200 microg/kg/min) after the loading dose (given for 10, 10, and 5 minutes, respectively) in advance of each maintenance concentrations. Measurements were taken at the end of each loading dose and at 25 and 35 minutes during each maintenance level. The same animals on a different day were given dextrose 5% and acted as the control. Phase 2: Dogs were studied on a single occasion during an infusion of lidocaine at 120 microg/kg/ min given after the loading dose (10 minutes). Measurements occurred after the loading dose and at 25 and 35 minutes. A blood sample for lidocaine concentration was taken at 70 minutes. Data were compared using a one-way ANOVA for phase 1, and between phase 1 and 2. Statistical analysis for phase 2 was performed using a paired t-test with a Bonferroni correction. A P value < or = .05 was considered significant. RESULTS Phase 1: Plasma lidocaine concentrations achieved with 40, 120, and 200 microg of lidocaine/kg/min were 2.70, 5.27, and 7.17 microg/mL, respectively. A significant increase in heart rate (HR) (all concentrations), central venous pressure (CVP), mean pulmonary arterial pressure (PAP), and a decrease in stroke index (SI) (200 microg/kg/min) were observed. An increase in systemic vascular resistance (SVR) and mean PAP, and a decrease in SI also followed the loading dose given before the 200 microg/kg/min infusion. No other significant differences from the control measurements, during dextrose 5% infusion alone, were detected. Phase 2: Plasma lidocaine concentrations achieved were 5.35, 4.23, 4.23, and 5.60 microg/mL at 10, 25, 35, and 70 minutes, respectively. They were not significantly different from concentrations found in our healthy dogs at the same infusions. A significant but small increase in CVP compared with baseline was noted after the loading dose. There were no significant differences from baseline shown in all other cardiovascular data. There were no statistically significant differences in any measurements taken during the lidocaine infusion between the dogs in phase 1 and phase 2. Dogs with aortic stenosis tended to have a lower cardiac index than healthy dogs at baseline (88 v 121 mL/kg/min) and during lidocaine infusion (81 v 111 mL/kg/min). A small, statistically significant difference in systolic PAP was present at baseline. CONCLUSIONS There does not appear to be any detrimental cardiovascular effects related to an infusion of lidocaine at 120 microg/kg/min during isoflurane anesthesia in healthy dogs or dogs with aortic stenosis. The technique used in this study resulted in therapeutic plasma concentrations of lidocaine. CLINICAL RELEVANCE Methods shown in the study can be used in clinical cases to achieve therapeutic lidocaine levels without significant cardiovascular depression during isoflurane anesthesia.
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Affiliation(s)
- A Nunes de Moraes
- Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Ontario, Canada
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Krejcie TC, Avram MJ, Gentry WB, Niemann CU, Janowski MP, Henthorn TK. A recirculatory model of the pulmonary uptake and pharmacokinetics of lidocaine based on analysis of arterial and mixed venous data from dogs. JOURNAL OF PHARMACOKINETICS AND BIOPHARMACEUTICS 1997; 25:169-90. [PMID: 9408858 DOI: 10.1023/a:1025780012960] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Pulmonary uptake of basic amine xenobiotics such as lidocaine may influence the onset of drug effect and ameliorate toxicity. To date, pharmacokinetic analysis of pulmonary drug uptake has been only semiquantitative and ill-suited for relating pharmacodynamics to pharmacokinetics or for estimating the time course of the fraction of drug dose residing in the lung during a single pass. We have developed recirculatory models in an experiment in which lidocaine was injected into the right atrium simultaneously with markers of intravascular space (indocyanine green) and total body water (antipyrine); this was followed by rapid arterial and mixed venous blood sampling. Such models are interpretable physiologically and are capable of characterizing the kinetics of the pulmonary uptake of lidocaine in addition to peripheral tissue distribution and elimination. The apparent pulmonary tissue volume of lidocaine (39 ml/kg) was nearly ninefold greater than that of antipyrine (4.5 ml/kg). The recirculatory model characterized both arterial and mixed venous data, but the latter data were not essential for estimating lidocaine's pulmonary disposition either before or after recirculation of drug was evident.
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Affiliation(s)
- T C Krejcie
- Northwestern University Medical School, Department of Anesthesiology, Chicago, Illinois 60611-3008, USA
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Warner KG, Quinn CC, Klein RD, Connolly RJ. Use of an adjustable tourniquet to reverse cyanosis in the newborn pig. Ann Thorac Surg 1997; 63:456-8. [PMID: 9033319 DOI: 10.1016/s0003-4975(96)00959-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Previous surgical models of cyanosis have been permanent. Because normal oxygenation was not restored in these models, it is unclear whether the metabolic changes produced by prolonged exposure to hypoxemia are irreversible. We therefore designed an experimental model of cyanosis that is reversible. METHODS The left atrial appendage was anastomosed directly to the main pulmonary artery in 8 piglets, aged 2 to 4 weeks. RESULTS The oxygen saturation fell from 95.3% +/- 0.8% to 72.4% +/- 3.9% (p < 0.001). A tourniquet was placed around the anastomosis to produce incremental changes in the level of cyanosis. Complete tourniquet occlusion resulted in obliteration of the right to left shunt, with return of systemic oxygen saturation to baseline levels. Systemic, left atrial, and pulmonary pressures did not change during the study. CONCLUSIONS In this acute preparation, stable hemodynamic conditions were maintained despite substantial variations in systemic levels of oxygenation. Most important, this model allows reversal of cyanosis with the return of normal oxygenation. Application of this experimental design in a chronic model may help to determine whether the metabolic effects of prolonged hypoxemia are potentially reversible.
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Affiliation(s)
- K G Warner
- Division of Cardiothoracic Surgery, New England Medical Center, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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Cassidy SC, Jones PR, Cox S, Walson PD, Allen HD. Serum lidocaine concentrations after subcutaneous administration in patients undergoing cardiac catheterization in a pediatric institution. J Pediatr 1996; 129:464-6. [PMID: 8804342 DOI: 10.1016/s0022-3476(96)70085-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE We wished to determine serum lidocaine concentrations after subcutaneous injection during cardiac catheterization. METHOD Serum lidocaine concentrations were measured in 50 patients during catheterization. RESULTS Serum concentration was linearly related to dose per kilogram of body weight. Lidocaine concentrations were therapeutic in 38% of patients. CONCLUSION Lidocaine dose must be considered when the drug is used for local anesthesia in children.
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Affiliation(s)
- S C Cassidy
- Department of Pediatrics, Ohio State University, Columbus, USA
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Tanaka K, Oda Y, Asada A, Fujimori M, Funae Y. Metabolism of lidocaine by rat pulmonary cytochrome P450. Biochem Pharmacol 1994; 47:1061-6. [PMID: 8147905 DOI: 10.1016/0006-2952(94)90418-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The metabolism of lidocaine was studied using microsomes from extrahepatic tissues of rats, including lung, kidney and brain, or using a reconstituted system with purified CYP2B1 and CYP4B. Rat pulmonary microsomes metabolized lidocaine to an N-deethylated metabolite, monoethylglycinexylidide (MEGX). Renal microsomes produced MEGX and 3-hydroxylidocaine (3-OH LID), although the rate of MEGX formation was much lower in renal than in pulmonary microsomes. Other metabolites were not detected. Lidocaine was not metabolized by brain microsomes. In extrahepatic tissues, pulmonary microsomes had the highest activity. Hence, two major forms of cytochrome P450 isozymes, CYP2B1 and CYP4B1, in rat pulmonary microsomes were used for further study. The study with a reconstituted system using purified cytochrome P450 isozymes revealed that only CYP2B1 showed lidocaine deethylation activity; the other form of cytochrome P450 in the lung, CYP4B1, did not. The Michaelis-Menten constant for lidocaine N-deethylation by rat pulmonary microsomes was 0.27 mM. Antibody against CYP2B1 completely inhibited the formation of MEGX by pulmonary microsomes. These results suggest that lidocaine is metabolized by rat lung, including CYP2B1.
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Affiliation(s)
- K Tanaka
- Department of Anesthesiology and Intensive Care Medicine, Osaka City University Medical School, Japan
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Affiliation(s)
- M Yaster
- Department of Anesthesiology, Johns Hopkins Medical Institutions, Baltimore, MD 21205
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Weiss BM, Atanassoff PG. Cyanotic congenital heart disease and pregnancy: natural selection, pulmonary hypertension, and anesthesia. J Clin Anesth 1993; 5:332-41. [PMID: 8373615 DOI: 10.1016/0952-8180(93)90130-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Pregnancy carries substantial maternal and fetal risks in patients with uncorrected or palliatively corrected cyanotic congenital heart disease (CHD). In tricuspid valve Ebstein's anomaly, pregnancy is well tolerated. Maternal mortality in tetralogy of Fallot seems to be less than 10%, but it exceeds 50% in Eisenmenger's syndrome and primary pulmonary hypertension (PPH). Maternal hematocrit greater than 60%, arterial oxygen saturation lower than 80%, right ventricular hypertension, and syncopal episodes are poor prognostic signs. Maternal risk could be reduced by vaginal delivery. Continuous monitoring of arterial and central venous pressure, electrocardiography, and pulse oximetry are recommended for every anesthetic procedure. The use of a pulmonary artery catheter is controversial and probably should be avoided in parturients with cyanotic CHD or PPH. The choice of anesthetic technique and drugs per se is of secondary importance and should be governed by individual preferences. Titration of anesthetic drugs, general anesthesia with controlled ventilation, or, preferably, regional anesthesia with spontaneous breathing should be used cautiously to avoid worsening of the preexisting condition. Prevention of excessive erythrocytosis, volume and blood loss substitution, cardiocirculatory pharmacologic support, prophylaxis of infective endocarditis, and judicious use of anticoagulant drugs should be applied as indicated by the type and presentation of CHD. Poor outcome of pregnancy in PPH requires an early consideration of heart-lung or lung transplantation. Multidisciplinary team effort and prolonged monitoring in the intensive care unit are mandatory to ensure a favorable outcome for cyanotic CHD and PPH parturients.
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Affiliation(s)
- B M Weiss
- Institute of Anesthesiology, University Hospital Zurich, Switzerland
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Burrows FA, Lerman J, LeDez KM, Strong HA. Pharmacokinetics of lidocaine in children with congenital heart disease. Can J Anaesth 1991; 38:196-200. [PMID: 2021989 DOI: 10.1007/bf03008144] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The purpose of this study was to determine the pharmacokinetics of lidocaine in children with congenital heart disease (CHD). Fifteen children with left to right intracardiac shunting of blood (acyanotic group) and 15 children with right to left intracardiac shunting of blood (cyanotic group) were studied and compared with 15 children without CHD (control group). Lidocaine (1.5 mg.kg-1) was injected into a peripheral vein over 30 sec and serial samples of arterial blood were obtained up to 120 min after completion of the infusion. Total and free lidocaine were analyzed by enzyme immunoassay. The serum concentration of alpha 1-acid glycoprotein (alpha 1-AGP) at induction of anaesthesia was measured in the three groups by radial immunodiffusion. The percent free lidocaine (100 x [free lidocaine]/[total lidocaine]) was greater at 30 sec post-infusion in all three groups (35-37%) than it was at any other time but was not significantly different among the three groups (P less than 0.05). There was no significant difference in either the percent free or the total lidocaine concentration at any sample time or in any of the pharmacokinetic variables among the three groups. The serum concentration of alpha 1-AGP did not differ significantly among the three groups of patients. We conclude that the presence of intracardiac shunts does not alter the pharmacokinetic behaviour of intravenous lidocaine (1.5 mg.kg-1) in children. The percent free lidocaine is greatest immediately post-injection and this may mitigate against rapid bolus administration of intravenous lidocaine in children.
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Affiliation(s)
- F A Burrows
- Department of Anaesthesia, Hospital for Sick Children, University of Toronto, Ontario, Canada
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