Claude Ecoffey

Major complications of regional anesthesia in France: The SOS Regional Anesthesia Hotline Service.

Background Several previous surveys have estimated the rate of major complications that occur after regional anesthesia. However, because of the increase in the use of regional anesthesia in recent years and because of the introduction of new techniques, reappraisal of the incidence and the characteristics of major complications is useful. Methods All French anesthesiologists were invited to participate in this 10-month prospective survey based on (1) voluntary reporting of major complications related to regional anesthesia occurring during the study period using a telephone hotline service available 24 h a day and managed by three experts, and (2) voluntary reporting of the number and type of regional anesthesia procedures performed using pocket booklets. The service was free of charge for participants. Results The participants (n = 487) reported 56 major complications in 158,083 regional anesthesia procedures performed (3.5/10,000). Four deaths were reported. Cardiac arrest occurred after spinal anesthesia (n = 10; 2.7/10,000) and posterior lumbar plexus block (n = 1; 80/10,000). Systemic local anesthetic toxicity consisted of seizures only, without cardiac toxicity. Lidocaine spinal anesthesia was associated with more neurologic complications than bupivacaine spinal anesthesia (14.4/10,000 vs. 2.2/10,000). Most neurologic complications were transient. Among 12 that occurred after peripheral nerve blocks, 9 occurred in patients in whom a nerve stimulator had been used. Conclusion This prospective survey based on a free hotline permanent telephone service allowed us to estimate the incidence of major complications related to regional anesthesia and to provide a detailed analysis of these complications.

Epidemiology and morbidity of regional anesthesia in children: a follow-up one-year prospective survey of the French-Language Society of Paediatric Anaesthesiologists (ADARPEF).

Background:  The French‐Language Society of Paediatric Anaesthesiologists (ADARPEF) designed a 1‐year prospective, multicenter and anonymous study to update both epidemiology and morbidity of regional anesthesia in children.

Efficacy of an Epidural Test Dose in Children Anesthetized with Halothane

The effect of an intravenous (iv) injection of lidocaine with epinephrine was studied to determine if such a test dose would cause a reliably detectable increase in heart rate and systemic blood pressure in children anesthetized with halothane and nitrous oxide. The effect of the injection of atropine before the test dose on these parameters was also determined. Sixty-five children 1 month to 11 yr of age and weighing 3.9-35 kg were studied. The children were assigned to one of four groups, each of which was anesthetized with 1% halothane and 50% nitrous oxide. Group 1 (n = 20) received 10 micrograms/kg atropine followed 5 min later by an iv dose of 0.1 ml/kg 1% lidocaine with 1/200,000 epinephrine (0.5 micrograms/kg) to simulate an intravascularly administered epidural test dose. Group 2 (n = 21) was identical to group 1 but did not receive atropine prior to the simulated intravascular test dose. Groups 3 (n = 12) and 4 (n = 11) were identical to groups 1 and 2, but the simulated intravascular test dose did not contain epinephrine: group 3 received atropine prior to the test dose and group 4 did not. The simulated intravascular test dose increased heart rate in group 1 (with atropine) at each time period from 15 to 120 s, but only at 45 and 60 s in group 2 (without atropine). Following the iv test dose, 6 of 21 children in group 2 had an increase in heart rate of less than 10 beats/min, while only one child in group 1 had an increase in heart rate of less than 10 beats/min. Intravenous test doses that did not contain epinephrine (groups 3 and 4) had no effect on heart rate or blood pressure. Atropine, 10 micrograms/kg, improves the reliability of an epidural test dose in children anesthetized with halothane and nitrous oxide but does not ensure total reliability in detecting an intravascular injection.

Premedication in children: hypnosis versus midazolam

Background:  The main objectives of premedication in children are to facilitate the separation from the parents, to reduce preoperative anxiety, to smooth the induction of anesthesia and to lower the risk of postoperative behavioral disorders. The most common technique is sedative premedication with midazolam. Hypnosis enables a state of relaxation to be achieved and has never been evaluated as a premedication technique. The aim of the present study was to evaluate the efficacy of hypnosis on anxiety and perioperative behavioral disorders versus midazolam.

Relationship Between Complications of Pediatric Anesthesia and Volume of Pediatric Anesthetics

a ZO-gauge, loo-cm long catheter is not easy because the length and the diameter of the catheter offer significant resistance. The feasibility of blood injected into the epidural space entering the subarachnoid compartment through the previous dural sac puncture remains unproven. In this particular case, it seems that the autologous blood was injected through the catheter, which was located intrathecally rather than epidurally. Administration of blood into a catheter under these circumstances may be ill advised; for one, it may not be necessary because not all the patients who have dural punctures develop postdural puncture headache (PDPH) (5,6). Second, because the location of the distal tip of the catheter is not exactly known, it is best not to use it as a vehicle for EBP injection (7). In this case, when the blood was injected, it resulted in an intrathecal hematoma that was present even two weeks after the catheter insertion. Clinically, the patient has continued to experience typical symptoms of ARC, including burning on both feet, low back pain, and low-grade fever with headaches and frequent diaphoresis. The most common causes of noninfectious ARC are chemical irritation produced by oil-based dyes previously used for myelograms (8,9), the intrathecal injection of blood, which has been also shown to produce neurological deficit in dogs (lo), and entry of blood into the intrathecal space during spinal surgical interventions (11). Arachnoiditis has also been found after subarachnoid hemorrhage (12) but is even more likely to occur when blood is also found after administration of pantopaque, a dye used to perform myelograms (13,14). For decades, pantopaque was used as contrast medium to obtain myelograms, and it was considered safe. Ironically, in the past, the only way to diagnose arachnoiditis was with a myelogram. Recently, thousands of patients with arachnoiditis caused by this procedure have been diagnosed by MRI; central clumping of spinal nerve roots as described in this patient has been identified as one of the radiological signs of this disease (15,16). Adherence of roots to the dural sac is more likely to happen after dural entry during surgery. Although no warning has been given about the possibility of this occurrence when EBPs are administered prophylactically, either through the same catheter or in a separate injection, the feasibility of arachnoiditis, a life-long serious complication, is factual.

Complications and fiberoptic assessment of size 1 laryngeal mask airway.

In pediatric practice, complications due to the laryngeal mask airway (LMA) have been studied with size 2 LMA, but not with size 1 LMA. We, therefore, compared prospectively the complications induced by LMA size 1 and 2 in 141 children aged 21 days to 11 yr. Intraoperative and lowest SpO2 values after removal of LMA were recorded. The following complications were recorded: cough, laryngospasm, bronchospasm, apnea, and airway obstruction. In 14 patients in the size 1 LMA group and 26 patients in the size 2 LMA group, pharyngolaryngeal structures were checked with fiberoptic examination. The number of attempts, complications, intraoperative SpO2, and lowest SpO2 values were similar when using size 1 and size 2 LMA. Fiberoptic examination of size 1 LMA showed a high incidence of impinging of the epiglottis in the LMA bars without airway obstruction. In conclusion, there was no difference in the complication rate between the two pediatric sizes of LMA when used in pediatric patients.

Tourniquet pain in a volunteer study: effect of changes in cuff width and pressure

This study examines the relationship between pneumatic tourniquet cuff size, occlusion pressure and the resulting pain. Two tourniquet cuff widths were used, a wide (14 cm) and a narrow cuff (7 cm). Twenty volunteers were divided into two groups for tourniquet application: a pressure group in which the tourniquet was inflated to a pressure equal to the systolic pressure + 100 mmHg, and a saturation group in which the tourniquet was inflated to 10 mmHg above the loss of arterial pulse, as indicated by cessation of pulse waveform on an oximeter. According to a randomised cross‐over protocol, subjects were studied using wide and narrow cuffs simultaneously and/or successively on both arms. Pain was assessed by subjects by means of a visual analogue score (0–10 cm). Occlusion pressures were similar for all volunteers in the pressure group and significantly higher than those in the saturation group with both the wide and narrow tourniquets. The wide cuff data turned out to be significantly lower than the narrow cuff results. Subjects in the pressure group could tolerate pain with the narrow cuff for significantly longer than with the wide cuff. However, in the saturation group, volunteers tolerated the wide cuff for longer. Pain intensity increased more rapidly in those in the pressure group with the wide cuff than with the narrow cuff. In contrast, volunteers in the saturation group found the narrow cuff to be more painful than the wide cuff. In conclusion, this study has shown that a wide tourniquet cuff is less painful than a narrow cuff if inflated at lower pressures and at these lower pressures it is still effective at occluding blood flow.

Infraclavicular block with lateral approach and nerve stimulation: Extent of anesthesia and adverse effects

Background and Objectives The infraclavicular approach to the brachial plexus is little used despite theoretical advantages of the technique. Using a vertical paracoracoid approach, we assessed the extent of the sensory block and the incidence of adverse effects. Methods After obtaining informed consent, 100 patients undergoing surgical procedures distal to the elbow were evaluated. The block was performed using a peripheral nerve stimulator. The puncture site was located in the infraclavicular fossa; the direction of the insulated needle was perpendicular to the skin. Motor response was sought in the hand or wrist at ≤ 0.6 mA. A total of 40 mL of 1.5% mepivacaine was administered as a single injection. The sensory block was evaluated every 5 minutes for 30 minutes before surgery in the cutaneous distribution of terminal branches of the brachial plexus. Results When one considers the cutaneous distributions of the median, ulnar, radial, and musculocutaneous nerves, the success rate was 89% for surgery without need for additional peripheral nerve blocks or general anesthesia. In contrast, cutaneous areas innervated by the axillary and medial cutaneous nerves were rarely anesthetized. We were unable to demonstrate a correlation between the intensity of the stimulation and the success of the block. On the other hand, a correlation was found between tourniquet sensation and the absence of anesthesia of the medial cutaneous nerve of the arm. Local anesthetic toxicity, Horner’s syndrome, and vascular puncture were respectively observed in 1%, 4%, and 5% of cases. The depth of the needle introduction was correlated with the body mass index (P < .001; r = .63). Conclusion Single injection infraclavicular block, using a vertical paracoracoid approach, appears suitable for surgery distal to the elbow. Selective anesthesia of the medial cutaneous nerve is useful in improving tolerance of the tourniquet.

Pharmacokinetics and analgesic effect of ropivacaine following ilioinguinal/iliohypogastric nerve block in children

Background: The aim was to investigate the efficacy, tolerance and pharmacokinetics of ropivavcaine when administered for ilioinguinal/iliohypogastric block in children.

Effects of Age on Plasma Protein Binding of Sufentanil

The plasma protein binding of sufentanil has been studied in newborns, infants (0.5 +/- 0.3 yr), children (6.8 +/- 3.0 yr), and adults (39.5 +/- 9.0 yr). Binding of sufentanil was determined in vitro by equilibrium dialysis, and radioactive tritiated sufentanil was used for the determination of drug concentrations in plasma and buffer. The free fraction of sufentanil was significantly higher in the newborn (19.5 +/- 2.7%; P less than 0.01) than in the other age groups. The free fraction was also significantly higher in infants (11.5 +/- 3.2%; P less than 0.01) than in children (8.1 +/- 1.4%) or in adults (7.8 +/- 1.5%) but did not differ significantly between children and adults. The free fraction of sufentanil was strongly correlated with the alpha 1-acid glycoprotein plasma concentration (r = -0.73; P less than 0.001) whereas it was weakly correlated with albumin plasma concentration (r = -0.35; P less than 0.05). These data suggest that the lower concentration of alpha 1-acid glycoprotein in newborns and infants probably accounts for the decrease in protein binding of sufentanil in these age groups when compared with that in older children or adults. The increased free fraction in the neonate might contribute to the enhanced effects of lipophilic opioids in the neonate.