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ABSTRACT: The use of a flexible or rigid fiberoptic bronchoscope belongs to the standard repertoire in anesthesiology. Besides a lack of training these procedures may be considerably compromised by endoscopic lens fogging. Several antifogging approaches are commercially available but to date no controlled studies regarding the efficacy of these devices in bronchoscopes exists. The aim of the present study was to compare the efficacy of different commercially available anti-fogging techniques for rigid and flexible bronchoscopes.
The study was performed at the department of anesthesia in a university children's hospital. An artificial airway model was created to simulate in vivo conditions with respect to airflow, temperature and atmospheric moisture. A test picture was inserted into the artificial airway for assuring a standardized view through the bronchoscopes. Antifogging efficacy of two liquid antifog solutions (Ultrastop and Anti-Fog), two antifog wipes (Lina Clear and Reso Clear) and an induction endoscope preheater system (used after one and two induction preheating phases) was assessed by video taping of the bronchoscope view of the test picture. In addition the administration of continuous oxygen airflow of 2 l min(-1) through the suction channel of the flexible bronchoscope was tested as an alternative method to prevent lens fogging. All final pictures were rated by 10 staff anesthesiologists who were blinded to the antifog devices used. To assess the clinical relevance of the results, ratings were classified into a 5 grade rating scale (ranging from no visualization of any structure to excellent endoscopic view allowing safe endotracheal intubation). In addition, the failure rate of each anti-fog technique was calculated.
A total of 300 endoscopic test pictures were taken and assessed. Using the flexible bronchoscope, the use of anti-fog solution (failure rate 3 %) and Lina Clear wipes (failure rate 4%) showed the best results. In the rigid bronchoscope group Ultrastop solution (failure rate 5 %) and Lina Clear wipes (failure rate 3.5 %) showed superior results. The two-time use of the endoscope preheater system was effective using flexible (failure rate 6 %) and rigid bronchoscopes (failure rate 10 %). The application of a continuous oxygen flow of 2 l/min failed to provide a clear endoscopic view (failure rate 93.5 %).
All commercially available antifog liquids and wipes showed slightly different reduction of lens fogging. However, other factors such as frequency of usage, the type of endoscope, hygiene properties as well as cost-effectiveness might have a substantial impact on the comparison of all tested anti-fog devices. The use of an endoscope preheater system might be a conceivable alternative method to reduce lens fogging despite the higher initial cost. However, the multiple use of the preheater system cannot be recommended at present as additional handling procedures to ensure an appropriate but safe temperature of the endoscopic tip should be provided by the manufacturer. Application of a continuous oxygen flow was shown not to be effective in preventing lens fogging using a flexible fiberoptic bronchoscope.
Der Anaesthesist 12/2012; 61(12):1036-44. · 0.99 Impact Factor
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ABSTRACT: HintergrundVerschiedene Untersuchungen und Fallberichte bestätigten die Wirksamkeit von Intralipid® (Sojabohnenöl, Eiphospholipide, Glyzerin,
Wasser) zur Therapie der Lokalanästhetikaintoxikation. Mit Intralipid® vorbehandelte Ratten tolerierten deutlich höhere Dosen
Bupivacain bis zum Eintritt der Asystolie als unbehandelte Tiere. Ob eine Propofolanästhesie in klinisch üblicher Dosierung
die therapeutische Sicherheit von Bupivacain bei akzidentell-intravasaler Injektion erhöht, ist zurzeit nicht bekannt. Die
vorgestellte Arbeit untersuchte diesen Zusammenhang.
Material und MethodeEs wurden 30Schweine (4,5–6,5kg schwer, 2 bis 6Wochen alt) mit Sevofluran (GruppeS) oder Propofol 10mg/kgKG/h plus Sevofluran
(GruppePS) anästhesiert. Nach 1h wurde Blut zur Bestimmung der Triglyzeridplasmakonzentration asserviert. Anschließend wurde
0,125%ige Bupivacainlösung mit 4mg/kgKG/min über einen zentralen Venenkatheter infundiert, bis der mittlere arterielle Druck
(MAD) auf 50% abgefallen war. Daraufhin wurde die Bupivacaininfusion gestoppt und sofort Blut für die Bestimmung der Bupivacainplasmakonzentration
abgenommen. Der Spontanverlauf der Hämodynamik wurde beobachtet. Resultate werden in Median, Minimum und Maximum angegeben.
ErgebnisseDie verabreichte Bupivacainmenge betrug in beiden Gruppen 9mg/kgKG (GruppeS 6–13mg/kgKG, GruppePS 5–13mg/kgKG). Die resultierenden
Bupivacainplasmakonzentrationen lagen bei 180μmol/l (83–686μmol/l) für GruppeS und bei 185μmol/l (130–465μmol/l) für
GruppePS. Trotz signifikant höherer Triglyzeridplasmakonzentrationen in GruppePS konnte zwischen den beiden Gruppen kein
signifikanter Unterschied gefunden werden, weder in der verabreichten Bupivacainmenge noch in den resultierenden Plasmakonzentrationen.
Die Zeiten bis zum Herz-Kreislauf-Stillstand waren vergleichbar.
SchlussfolgerungIn dieser Versuchsreihe an Schweinen konnte Propofol, formuliert in einer 50:50 mittel-/langkettigen Lipidemulsion, die therapeutische
Sicherheit von Bupivacain (bei intravasaler Applikation) nicht erhöhen.
BackgroundSeveral reports have confirmed the efficacy of Intralipid® (containing soya bean oil, egg phospholipids, glycerin and water)
in the therapy of systemic local anesthetic intoxication. Pretreatment with Intralipid® shifted the dose-response to bupivacaine-induced
asystole in rats. Whether intravenous anesthesia with propofol in the widely used medium chain triglyceride lipid emulsion
increases the therapeutic range of systemically administered bupivacaine or not is unknown and was investigated in this study.
MethodsA total of 30 piglets aged 2–6 weeks and weighing 4.5–6.5kg were randomized into 2 groups and anesthetized with sevoflurane
(group S) alone or with propofol 10mg/kg body weight (BW)/h plus sevoflurane (group PS). After 60min of steady state anesthesia
arterial blood was sampled for assessment of blood gases, acid-base state and triglyceride plasma concentrations. Thereafter
bupivacaine 0.125% was continuously infused by an infusion syringe pump through a central venous line at a rate of 4mg/kg
BW/min until invasively measured mean arterial pressure (MAP) was reduced by 50% of initial value. The bupivacaine infusion
was stopped, blood for assessment of bupivacaine plasma concentration was drawn and the spontaneous hemodynamic course was
observed. Resuscitation was not attempted. Results are presented as median and range. The Mann-Whitney U-test was used to
assess differences between the two groups for triglyceride as well as for bupivacaine plasma concentrations measured at MAP
50%. A p-value≤0.05 was considered to be significant.
ResultsBaseline conditions (arterial blood pH, plasma protein and triglyceride plasma concentrations) did not differ significantly
between the two groups. After 1h of anesthesia, triglyceride plasma concentrations were significantly increased in group
PS (median 0.69mmol/l) compared to the corresponding baseline values (median 0.14mmol/l; p<0.001) and to the 1h values
of group S (median 0.16mmol/l; p<0.001). The total amount of bupivacaine administered was 9mg/kg BW in both groups (6–13mg/kg
BW in group S, 5–13mg/kg BW in group PS). Resulting bupivacaine plasma concentrations were 180μmol/l (83–686μmol/l) in
group S and 185μmol/l (130–465μmol/l) in group PS. However, the total amount of bupivacaine administered and bupivacaine
plasma concentrations at MAP 50% did not reveal statistically significant differences between the two groups but a huge variability
of both parameters within each group was observed. None of the 30 piglets spontaneously recovered and they died from pulseless
electrical activity or from asystolic cardiac arrest. The time from MAP 50% until cardiac arrest demonstrated a large variability
but did not reveal significant differences between the two groups. The time to cardiac arrest was similar in both groups.
ConclusionMedium/long chain triglyceride lipid emulsion (50:50) as widely used in propofol solutions did not increase therapeutic safety
in cases of intravascular bupivacaine administration in this piglet model.
SchlüsselwörterLokalanästhetika–Asystolie–Hämodynamik–Lipidemulsion, intravenöse
KeywordsAnesthetics, local–Heart arrest–Hemodynamics–Fat emulsions, intravenous
Der Anaesthesist 05/2012; 60(9):814-818. · 0.99 Impact Factor
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ABSTRACT: HintergrundAn gesunden Kindern konnte gezeigt werden, dass intrathekal verabreichte Opioide eine sichere und effektive perioperative
Analgesie bei wirbelsäulenchirurgischen Eingriffen ermöglichen. Das Ziel der vorliegenden Untersuchung ist es, ihre Anwendbarkeit
bei schwer- und schwerstbehinderten Kindern für wirbelsäulenchirurgische Eingriffe zu überprüfen.
MethodeMit Zustimmung der lokalen Ethikkommission wurden Patienten vom Status3 und 4 der Klassifikation der American Society of
Anesthesiologists (ASA), die sich einem wirbelsäulenchirurgischen Eingriff unterziehen mussten, retrospektiv untersucht. Zusätzlich
zur Allgemeinanästhesie mit Sevofluran oder i.v.-verabreichtem Propofol erhielten die Patienten vor der Operation 20µg/kgKG
Morphin und 1,5µg/kgKG Sufentanil intrathekal. Nach Beendigung des Eingriffs wurde eine Nalbuphindauerinfusion gestartet.
Der Bedarf an zusätzlichen intra- und postoperativen Analgetika, der Zeitpunkt der Extubation, die postoperativen Schmerz-Scores
und die arteriellen Kohlendioxidpartialdruck- (paCO2)-Werte sowie das Auftreten unerwünschter Nebenwirkungen wurden untersucht.
ErgebnisseEs wurden 28Patienten im Alter von 2,8 bis 18,5Jahren (Median 11,6Jahre) untersucht. Unmittelbar im OP konnten 17Patienten
extubiert werden; bei 11Patienten entschied man sich zu einer verzögerten Extubation. Bis auf einen Patienten mit postoperativer
Massivtransfusion konnten alle innerhalb von 24h extubiert werden. Eine adäquate postoperative Analgesie mit Schmerz-Scores
≤3 wurde mithilfe der Kombination von intrathekal verabreichten Opioiden mit Nalbuphin postoperativ bei 26 von 28Patienten
(93%) erreicht. Bei 2Patienten war der Wechsel auf eine i.v.-Morphin-Gabe erforderlich. Postoperative Übelkeit und Erbrechen
(„postoperative nausea and vomiting“, PONV), Pruritus und leichte Hypoventilation mit paCO2-Werten zwischen 5,2 bis 9,7kPa (Median 6,3kPa) waren die beobachteten Nebenwirkungen.
SchlussfolgerungDer Einsatz intrathekal verabreichter Opioide, ergänzt durch eine postoperative Nalbuphininfusion, erlaubt in den allermeisten
Fällen eine frühzeitige Extubation ohne persistierende Atemdepression und ist eine praktikable sowie effektive Methode zur
postoperativen Analgesie bei schwer behinderten Kindern nach wirbelsäulenchirurgischen Eingriffen.
Purpose of the studyIntrathecal opioids have been shown to be safe and effective for postoperative analgesia in healthy children for spinal surgery.
The aim of this study was to evaluate the applicability of intrathecal opioids in severely handicapped children scheduled
for spinal surgery.
MethodsWith hospital ethical committee approval, patients with physical states III and IV of the ASA classification requiring spinal
surgery were retrospectively studied. In addition to inhalational anesthesia with sevoflurane or intravenous anesthesia using
propofol, morphine 20µg/kgBW and sufentanil 1.5µg/kgBW were administered intrathecally before surgery. After surgery an
infusion of nalbuphine was started. Need for additional intraoperative and postoperative analgesics, time of extubation, postoperative
pain scores and paCO2 values as well as adverse effects were recorded.
ResultsA total of 28 patients aged from 2.8 to 18.5 years (median 11.6 years) were studied. Immediate tracheal extubation in the
operating room was possible in 17 patients and for 11 patients delayed extubation was elected. All patients were extubated
within 24h except for 1 patient who received massive postoperative transfusions. In 26 out of 28 patients (93%) the combination
of intrathecal opioids with postoperative nalbuphine provided adequate analgesia. Observed side effects were post-operative
nausea and vomiting (PONV), pruritus and moderate hypoventilation. In two patients a change to intravenous morphine therapy
was necessary.
ConclusionThe use of intrathecal opioids for perioperative pain control from spinal fusion in severely handicapped children is feasible.
Intrathecal opioids provide adequate postoperative analgesia and allow early extubation without persisting relevant respiratory
compromise in most of these patients.
SchlüsselwörterOpioide-Intrathekal-Wirbelsäulenchirurgie-Kinder
KeywordsOpioids-Intrathecal-Spinal surgery-Children
Der Anaesthesist 04/2012; 59(7):614-620. · 0.99 Impact Factor
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ABSTRACT: Several reports have confirmed the efficacy of Intralipid® (containing soya bean oil, egg phospholipids, glycerin and water) in the therapy of systemic local anesthetic intoxication. Pretreatment with Intralipid® shifted the dose-response to bupivacaine-induced asystole in rats. Whether intravenous anesthesia with propofol in the widely used medium chain triglyceride lipid emulsion increases the therapeutic range of systemically administered bupivacaine or not is unknown and was investigated in this study.
A total of 30 piglets aged 2-6 weeks and weighing 4.5-6.5 kg were randomized into 2 groups and anesthetized with sevoflurane (group S) alone or with propofol 10 mg/kg body weight (BW)/h plus sevoflurane (group PS). After 60 min of steady state anesthesia arterial blood was sampled for assessment of blood gases, acid-base state and triglyceride plasma concentrations. Thereafter bupivacaine 0.125% was continuously infused by an infusion syringe pump through a central venous line at a rate of 4 mg/kg BW/min until invasively measured mean arterial pressure (MAP) was reduced by 50% of initial value. The bupivacaine infusion was stopped, blood for assessment of bupivacaine plasma concentration was drawn and the spontaneous hemodynamic course was observed. Resuscitation was not attempted. Results are presented as median and range. The Mann-Whitney U-test was used to assess differences between the two groups for triglyceride as well as for bupivacaine plasma concentrations measured at MAP 50%. A p-value≤0.05 was considered to be significant.
Baseline conditions (arterial blood pH, plasma protein and triglyceride plasma concentrations) did not differ significantly between the two groups. After 1 h of anesthesia, triglyceride plasma concentrations were significantly increased in group PS (median 0.69 mmol/l) compared to the corresponding baseline values (median 0.14 mmol/l; p<0.001) and to the 1 h values of group S (median 0.16 mmol/l; p<0.001). The total amount of bupivacaine administered was 9 mg/kg BW in both groups (6-13 mg/kg BW in group S, 5-13 mg/kg BW in group PS). Resulting bupivacaine plasma concentrations were 180 μmol/l (83-686 μmol/l) in group S and 185 μmol/l (130-465 μmol/l) in group PS. However, the total amount of bupivacaine administered and bupivacaine plasma concentrations at MAP 50% did not reveal statistically significant differences between the two groups but a huge variability of both parameters within each group was observed. None of the 30 piglets spontaneously recovered and they died from pulseless electrical activity or from asystolic cardiac arrest. The time from MAP 50% until cardiac arrest demonstrated a large variability but did not reveal significant differences between the two groups. The time to cardiac arrest was similar in both groups.
Medium/long chain triglyceride lipid emulsion (50:50) as widely used in propofol solutions did not increase therapeutic safety in cases of intravascular bupivacaine administration in this piglet model.
Der Anaesthesist 07/2011; 60(9):814-8. · 0.99 Impact Factor
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ABSTRACT: This study investigated the effect of different tube cuff types and airway pressures on fluid leakage past the tracheal tube cuff during suction with a closed tracheal suction system (CTSS).
Unlubricated high-volume, low-pressure tracheal tube cuffs made from polyvinylchloride (PVC) and polyurethane (PU) with a size 7.5 mm internal diameter (ID) were placed in a 22 mm ID artificial trachea connected to a test lung and inflated to 25 or 50 cmH2O of cuff pressure. Positive pressure ventilation (PPV) with peak inspiratory pressures of 15, 20 or 25 cmH2O and positive end expiratory pressures (PEEP) of 5 or 10 cmH2O were used. A CTSS catheter (14 Fr) was attached to the tracheal tube and suction was performed for 5, 10, 15 or 20 s with 200 or 300 cmH2O of negative suction pressures. The volume of fluid leaking across the tube cuff at the end of the suction procedure was measured (mL), and the airway pressure was simultaneously recorded. Fluid leakage and airway pressures during different suction conditions were compared using a Kruskal Wallis test and Mann Whitney test (P<0.05).
The airway pressure drop during suction was similar for both tube cuffs. The PU tube cuff resulted in significantly less fluid leakage (range 0.00-0.12 mL) than the PVC tube cuff (P<0.001). For the PVC tube cuff, fluid leakage at higher cuff pressures was significantly less (P<0.01).Varying PEEP and PIP did not change the fluid leakage or the drop in airway pressure.
The use of PU tube cuffs and intermittent transient increases in cuff pressure during suction can effectively reduce fluid leakage past the tracheal tube during closed tracheal suctioning.
Minerva anestesiologica 02/2011; 77(2):166-71. · 2.66 Impact Factor
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ABSTRACT: It is controversial as to whether T-wave elevation is caused by local anaesthetics, epinephrine, or their combination. It has been shown that T-elevation after intravascular injection of a small bupivacaine test dose is caused by epinephrine and not by bupivacaine. The aim of this study was to investigate ECG changes with higher doses of i.v. bupivacaine.
Thirty neonatal pigs were anaesthetized with sevoflurane and their tracheas intubated and artificially ventilated. Under steady-state conditions, bupivacaine was continuously infused (flow rate 3.2 ml kg(-1) min(-1)) by a syringe infusion pump through a central venous catheter. Group 1 received bupivacaine 0.125%, Group 2 bupivacaine 0.5%. The ECG was continuously printed and subsequently analysed for alterations in heart rate, ventricular de- and repolarization, and arrhythmias at 1.25, 2.5, and 5 mg kg(-1) bupivacaine infused.
Sinus rhythm persisted in all pigs. Heart rate decreased progressively in both groups, but this was significantly more pronounced in Group 1. T-wave elevation occurred in 40% and 0% (Groups 1 and 2) at 1.25 mg kg(-1), in 80% and 0% at 2.5 mg kg(-1), and in 93% and 80% at 5 mg kg(-1) bupivacaine infused. There were significant differences between the two groups at 1.25 and 2.5 mg kg(-1) infused.
Higher doses of i.v. infused bupivacaine can cause T-elevation. With slower injection technique, T-elevation can already be detected at lower bupivacaine doses administered.
BJA British Journal of Anaesthesia 10/2010; 105(4):437-41. · 4.24 Impact Factor
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ABSTRACT: This study compared the fluid leakage in the new 'tapered' shaped against the classic 'cylindrical' shaped tracheal tube cuffs when placed in different sized tracheas.
The 7.5 mm internal diameter (ID) tracheal tube cuffs-Tapered Seal Guard (TSG), Standard Seal Guard (SSG), Hi-Lo, Microcuff, Ruesch, and Portex Profile-were compared in an in vitro apparatus. Vertical artificial tracheas with 16, 20, and 22 mm ID were intubated, 5 ml clear water was applied above the unlubricated tube cuffs, and fluid leakage was measured up to 60 min. Data of tapered vs non-tapered tube cuffs (16 observations) were compared for each tracheal diameter using the Mann-Whitney test.
Median (range) fluid leakage (ml) at 60 min was 2.14 (0.05-4.88), 1.14 (0.00-4.84), and 0.13 (0.00-1.32), respectively, for 16, 20, and 22 mm tracheas in the TSG tube studies when compared with 4.58 (0.44-4.88), 2.21 (0.00-4.81), and 0.00 (0.00-4.81) in the SSG tube and 4.54 (1.54-4.82), 0.90 (0.00-4.49), and 4.85 (4.40-4.99) in the Microcuff tube studies. Leakage in all polyvinylchloride (PVC) tube cuffs was almost complete (5 ml) within 5 min (P<0.001).
The tapered PU tube cuff was as effective as the cylindrical PU cuffs in smaller tracheal diameters and was more efficient than the cylindrical Microcuff PU tube cuff in larger tracheal diameter in preventing subglottic fluid leakage across the tube cuff tested in this in vitro study. PVC tube cuffs leaked much more and faster than PU cuffs.
BJA British Journal of Anaesthesia 10/2010; 105(4):538-43. · 4.24 Impact Factor
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ABSTRACT: This study aims to evaluate sevoflurane and anaesthetic gas consumption using uncuffed vs. cuffed endotracheal tubes (ETT) in paediatric surgical patients.
Uncuffed or cuffed ETT were used in paediatric patients (newborn to 5 years) undergoing elective surgery in a randomized order. Duration of assessment, lowest possible fresh gas flow (minimal allowed FGF: 0.5 l/min) and sevoflurane concentrations used were recorded. Consumption and costs for sevoflurane and medical gases were calculated.
Seventy children (35 uncuffed ETT/35 cuffed ETT), aged 1.73 (0.01-4.80) years, were enrolled. No significant differences in patient characteristics, study period and sevoflurane concentrations used were found between the two groups. Lowest possible FGF was significantly lower in the cuffed ETT group [1.0 (0.5-1.0) l/min] than in the uncuffed ETT group [2.0 (0.5-4.3) l/min], P<0.001. Sevoflurane consumption per patient was 16.1 (6.4-82.8) ml in the uncuffed ETT group and 6.2 (1.1-14.9) ml in the cuffed ETT group, P=0.003. Medical gas consumption was 129 (53-552) l in the uncuffed ETT group vs. 46 (9-149) l in the cuffed ETT group, P<0.001. The total costs for sevoflurane and medical gases were 13.4 (6.0-67.3)euro/patient in the uncuffed ETT group and 5.2 (1.0-12.5)euro/patient in the cuffed ETT group, P<0.001.
The use of cuffed ETT in children significantly reduced the costs of sevoflurane and medical gas consumption during anaesthesia. Increased costs for cuffed compared with uncuffed ETT were completely compensated by a reduction in sevoflurane and medical gas consumption.
Acta Anaesthesiologica Scandinavica 08/2010; 54(7):855-8. · 2.19 Impact Factor
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ABSTRACT: Intrathecal opioids have been shown to be safe and effective for postoperative analgesia in healthy children for spinal surgery. The aim of this study was to evaluate the applicability of intrathecal opioids in severely handicapped children scheduled for spinal surgery.
With hospital ethical committee approval, patients with physical states III and IV of the ASA classification requiring spinal surgery were retrospectively studied. In addition to inhalational anesthesia with sevoflurane or intravenous anesthesia using propofol, morphine 20 microg/kgBW and sufentanil 1.5 microg/kgBW were administered intrathecally before surgery. After surgery an infusion of nalbuphine was started. Need for additional intraoperative and postoperative analgesics, time of extubation, postoperative pain scores and p(a)CO2 values as well as adverse effects were recorded.
A total of 28 patients aged from 2.8 to 18.5 years (median 11.6 years) were studied. Immediate tracheal extubation in the operating room was possible in 17 patients and for 11 patients delayed extubation was elected. All patients were extubated within 24 h except for 1 patient who received massive postoperative transfusions. In 26 out of 28 patients (93%) the combination of intrathecal opioids with postoperative nalbuphine provided adequate analgesia. Observed side effects were post-operative nausea and vomiting (PONV), pruritus and moderate hypoventilation. In two patients a change to intravenous morphine therapy was necessary.
The use of intrathecal opioids for perioperative pain control from spinal fusion in severely handicapped children is feasible. Intrathecal opioids provide adequate postoperative analgesia and allow early extubation without persisting relevant respiratory compromise in most of these patients.
Der Anaesthesist 07/2010; 59(7):614-20. · 0.99 Impact Factor
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ABSTRACT: Origin of electrocardiographic (ECG) alterations during intravascular injection of local anaesthetic solutions is controversial. The aim of this study was to elucidate whether epinephrine, bupivacaine or their combination is responsible for ECG alteration.
Forty-five piglets were randomized into three groups. After induction of general anaesthesia using sevoflurane and peripheral venous cannulation, the trachea was intubated, the lungs were artificially ventilated, and anaesthesia was maintained by sevoflurane. Under steady state 0.2 ml kg(-1) and after 10 min 0.4 ml kg(-1) of one of the following three test solutions was administered i.v.: bupivacaine 0.125% (Group 1), bupivacaine 0.125%+epinephrine 1:200 000 (Group 2), and plain epinephrine 1:200,000 (Group 3). The ECG was analysed for alterations in heart rate and T-elevation.
After injection of 0.2 or 0.4 ml kg(-1) test solution, an increase in heart rate of at least 10% was found in none of Group 1 and in all of Groups 2 and 3. After application of 0.2 ml kg(-1) test solution, T-elevation was found in 7% of Group 1 and in 93% of Groups 2 and 3. The injection of 0.4 ml kg(-1) revealed a T-elevation in 27%, 100%, and 100%, respectively, in Groups 1, 2, and 3.
This animal model demonstrated that increases in heart rate and T-elevation in the ECG during i.v. application of a common test dose (0.2 ml kg(-1)) of bupivacaine are caused by epinephrine addition. Whether higher doses of bupivacaine alone can cause similar ECG changes or not requires further studies.
BJA British Journal of Anaesthesia 11/2009; 104(1):94-7. · 4.24 Impact Factor
