Median effective dose (ED50) of paracetamol and nefopam for postoperative pain: isobolographic analysis of their antinociceptive interaction.

BACKGROUND: The analgesic efficacy of nefopam and of paracetamol has been shown in the postoperative period after mild- and moderate-pain surgery. The aim of this study was to define the median effective analgesic doses of each drug and of their combination, in order to determine the nature of their interaction. METHODS: Ninety adult patients scheduled to undergo tonsillectomy under general anesthesia were enrolled in one out of three groups: nefopam group, or paracetamol group, or nefopam-paracetamol group. The median effective dose for each drug and also for their combination was defined using an up-and-down sequential allocation technique. The analgesic interaction of their combination was assessed using an isobolographic analysis. RESULTS: The median effective analgesic dose (median value and 95% confidence interval) of nefopam and paracetamol were 21.7 mg (21.1-22.3 mg) and 628 mg (600-656 mg), respectively. The median effective analgesic doses of the combination were 8.9 mg (8.7-9.1 mg) for nefopam and 265 mg (256-274 mg) for paracetamol. The isobolographic analysis demonstrated a supra-additive interaction of the two drugs. CONCLUSION: The combination of nefopam and paracetamol produces effective analgesia with a synergistic interaction.

Gabapentin premedication: assessment of preoperative anxiolysis and postoperative patient satisfaction.

BACKGROUND: Gabapentin reduces anxiety in psychiatric patients. In this prospective, randomized, double-blinded, placebo-controlled study, we investigated whether a single dose of gabapentin as a premedicant reduces preoperative anxiety, and improves patient satisfaction. MATERIALS AND METHODS: After Institutional Review Board approval and written consent, 210 patients were randomly allocated into 3 groups of oral premedication: placebo, hydroxyzine 75 mg, or gabapentin 1200 mg. Anxiety level was assessed 3 times, using a 100-mm visual analogue scale: before premedication, in the preoperative holding area, and just before induction of general anaesthesia. In the postoperative period, patients were asked about their satisfaction with their premedicant. Data were presented as mean +/- SD. VAS scores were analyzed by repeated-measures analysis of variance followed by a Bonferroni test as appropriate. The chi-square test was used to analyze categorical data. All p values less than 0.05 was considered statistically significant. RESULTS: Baseline anxiety was not statistically different among the 3 groups. Anxiety level in the gabapentin group was significantly lower in the holding area, and before induction of anaesthesia (20 mm +/- 21), than in the hydroxyzine group (33 mm +/- 26 ; p = 0.023) and in the placebo group (36 mm +/- 28; p = 0.004). Anxiety decreased significantly overtime only in the gabapentin group. The gabapentin and hydroxyzine groups had a higher proportion of "satisfied or extremely satisfied" patients (73% and 70% respectively) as compared to the placebo group (48%, p = 0.006). CONCLUSION: A single dose of gabapentin has proven to be an effective premedication to reduce preoperative anxiety.

Ketamine does not decrease postoperative pain after remifentanil-based anaesthesia for tonsillectomy in adults.

BACKGROUND: There are conflicting results concerning the pre-emptive effect of ketamine on central sensitization following surgery. The aim of this prospective, randomized, double-blind, placebo-controlled study was to assess the effect of the N-methyl-D-aspartate receptor antagonist ketamine on postoperative morphine consumption and pain score after remifentanil-based anaesthesia in adult patients scheduled for tonsillectomy. METHODS: We studied 40 adult patients undergoing elective tonsillectomy. Total intravenous anaesthesia was induced and maintained with remifentanil (0.125-1.0 microg kg(-1) min(-1)) and propofol target-controlled infusion. Patients in group K received a bolus dose of ketamine 0.5 mg kg(-1) immediately after anaesthetic induction, followed by a continuous infusion of 2 microg kg(-1) min(-1). Saline was administered in the same sequence in group S. Propofol, remifentanil, and the study drug infusions were discontinued at the end of surgery. RESULTS: Intraoperative remifentanil consumption (0.57 +/- 0.18 in group K vs. 0.55 +/- 0.14 microg kg(-1) min(-1) in group S), morphine requirement in the PACU (11 +/- 3 in group K vs. 9 +/- 4 mg in group S) and in the ward (22 +/- 11 in group K vs. 25 +/- 14 mg in group S), median time to first analgesia in the ward (338 +/- 126 in group K vs. 328 +/- 144 min in group S), and VAS pain scores were comparable in both groups. CONCLUSION: Small-dose of ketamine does not seem to be a useful adjunct to remifentanil-based anaesthesia during short, painful surgical procedures.

[Labour epidural analgesia in Martinique: evaluation of quality and accessibility to epidural analgesia by the patients in level one obstetric clinic]. / Analgésie péridurale de travail en Martinique: évaluation de la qualité et de l'accessibilité à l'analgésie péridurale par les parturientes dans une clinique obstétricale de niveau 1.

OBJECTIVES: The main aim of this study was to evaluate real-life experience and the quality of labor epidural analgesia (LEA) by the patients, from the anaesthesia consultation to leaving the clinic after childbirth. STUDY DESIGN: Descriptive study. PATIENTS AND METHODS: This study took place over a period of 8 weeks, at the level I obstetric clinic in Martinique. One hundred and thirty-four successive patients completed an anonymous questionnaire following childbirth. RESULTS: During the study period (134 patients completed the questionnaire, corresponding to 100% return) 127 women had asked for LEA (94%), which was possible in 94%, with a patient satisfaction level of 94% and an average mark for quality at 18/20. The quality of information given at the anaesthesia consultation was judged excellent for 97%, and 91% were reassured by the consultation. The delay between the demand and the LEA procedure was less than 15 min in 63%, and in 39% the procedure was done during the night. The procedure was painless in 63%, and 97% of women were ready to begin the same procedure again. CONCLUSION: This study seems to underline the fact that the needs and the acceptability of LEA are the same in Martinique as in mainland France. This study does not support the hypothesis of the cultural barrier to justify the low level of LEA in the Overseas Departments. An obvious result seems to be that good organization of anaesthesia and obstetric services results in a natural increase in LEA demand.

Neostigmine added to lidocaine axillary plexus block for postoperative analgesia.

BACKGROUND AND OBJECTIVE: We have assessed the analgesic efficacy and side-effects of neostigmine when added to lidocaine for axillary brachial plexus block, in a prospective, randomized, double-blind, placebo-controlled study. METHODS: We studied 34 ASA I or II patients undergoing elective ambulatory carpal tunnel release. Axillary brachial plexus block was performed using a peripheral nerve stimulator to locate the median nerve. All patients were administered 1.5% lidocaine 450 mg and epinephrine 5 microg mL-1. Patients were allocated randomly to one of two groups. Neostigmine 500 microg was added in group N, and saline 1 mL in group S. RESULTS: The duration of analgesia did not significantly differ between groups [mean (SD)]: 812.5 (456.9) for group S vs. 746.7 (474.1) min for group N (P > 0.05). The need for supplementary analgesia did not significantly differ between groups: 4.4 (1.5) extra doses for group S vs. 3.8 (2.2) extra doses for group N (P > 0.05). Visual analogue pain scores and occurrence of side-effects did not significantly differ between groups. CONCLUSION: Neostigmine does not seem to be of clinical value for peripheral nerve blocks.

Caudal clonidine for postoperative analgesia in adults.

We have assessed the analgesic efficacy and side effects of caudally administered clonidine in a prospective, randomized, double-blind, placebo-controlled study. We studied 64 adult patients undergoing elective haemorrhoidectomy. Caudal block was performed in all patients using a mixture of 0.5% bupivacaine 35 mg with 2% lidocaine 140 mg and epinephrine 5 micrograms ml-1. Patients were allocated randomly to one of two groups. Clonidine 75 micrograms was added in group C and saline 1 ml in group S. Median time to first analgesic requirements was significantly longer in group C (mean 729 (SD 120) min) than in group S (276 (131) min) (P = 0.01). Bradycardia occurred in seven patients in group C but did not affect mean arterial pressure.

[Opioid spinal anesthesia at the end of labor for potentially difficult deliveries]. / Rachianesthésie aux morphiniques en fin de travail pour expulsions par voie basse potentiellement difficiles.

We report two cases of difficult delivery, one vaginal breech presentation and one vaginal twin delivery in agitated parturients who were not given epidura analgesia. Maternal agitation was caused by pain and led to the risk of difficult fetal extraction. Epidural analgesia is not useful during the second stage of labor because of delayed onset of action of the administered drugs. Spinal injection of 10 microg of sufentanil was followed by rapid analgesia, maternal sedation and atraumatic deliveries. The usefulness of this technique is discussed for analgesia during the second stage of labor when epidural analgesia has not been performed.

Nasotracheal intubation in patients with immobilized cervical spine: a comparison of tracheal tube cuff inflation and fiberoptic bronchoscopy.

UNLABELLED: Tracheal intubation may pose problems in patients with cervical spine injury (CSI). In patients without CSI, the success rate of blind nasotracheal intubation is increased by endotracheal tube (ETT) cuff inflation in the pharynx. The purpose of this study was to assess the efficacy of ETT cuff inflation in the pharynx as an aid to blind nasotracheal intubation in patients with an immobilized cervical spine. The technique was compared with fiberoptic bronchoscopy. Twenty ASA physical status I and II patients undergoing elective surgery in which the trachea was to be intubated nasally were enrolled in this prospective, randomized study. The cervical spine of each patient was immobilized. The trachea of each patient was intubated twice, once using fiberoptic bronchoscopy and once blindly using the technique of ETT cuff inflation in the pharynx. A maximum of three attempts was allowed for intubation using ETT cuff inflation. A maximum of 3 min was allowed for intubation using fiberoptic bronchoscopy. When ETT cuff inflation was used, intubation was successful in 19 of 20 patients (95%); the first attempt at intubation was successful in 14 of 20 patients (70%). Intubation was successful in 19 of 20 patients (95%) when using fiberoptic bronchoscopy. Mean times to intubate were 20.8 +/- 23 s when the ETT cuff was inflated in the pharynx and 60.1 +/- 56 s when using fiberoptic laryngoscopy (P < 0.01). We conclude that both ETT cuff inflation in the pharynx and fiberoptic bronchoscopy are valuable for nasotracheal intubation in patients with an immobilized cervical spine and that ETT cuff inflation can be used as an alternative to fiberoptic bronchoscopy in patients with CSI. IMPLICATIONS: We compared the technique of endotracheal tube cuff inflation in the pharynx for blind nasotracheal intubation in patients with an immobilized cervical spine with fiberoptic bronchoscopy. There was no significant difference between the success rates of the techniques.

Caudal clonidine added to local anaesthetics for post-operative analgesia after anal surgery in adults - abstract

Duration of postopertive analgesia with caudal local anesthetics is increased by the addition of clonidine in children. To assess its efficacy in adults, we undertook a prospective, randomized, double-blind study in adults undergoing elective haemorrhoidectomy. Fifty-eight patients were randomly allocated to one of two groups. Caudal anaesthesia was performed with 0.5 percent isobarbic bupivacaine 35 mg (7 ml) in 2 percent lidocaine 140 mg (7 ml) and epinephrine 1/200000. Clonidine 75 mg was added in Group C, and saline (1ml) in group S. Duration of analgesia, defined as the time from the caudal injection to the first request for supplemental analgesics, was recorded as well as the time for the first micturition, haemodynamic changes and sedation. No differences were found between groups for demographic data, sedation and the time to first micturition. The mean (ñSEM) duration of analgesia was longer in group C(729 ñ 120 min) than in group S (276 ñ 131 min) (p=0.01). Hypotension and sedation was not marked in our study. Bradycardia was more frequent in the clonidine group but had no haemodynamic repercussions. We conclude that the duration of postoperative analgesia with caudal local anaesthetics was significantly increased by the addition of 75 mg of clonidine without major side effects. (AU)

Effect of preincision versus postincision infiltration with bupivacaine on postoperative pain.

STUDY OBJECTIVE: To compare the efficacy of preincision wound infiltration with bupivacaine to wound infiltration at the end of the operation. DESIGN: A prospective, randomized, double-blind study. SETTING: University medical center. PATIENTS: 56 ASA status I and II women scheduled for abdominal hysterectomy were randomly assigned to one of three treatment groups. INTERVENTIONS: Group 1 (control) received no local anesthetic infiltration. Group 2 received subcutaneous infiltration with 40 ml of bupivacaine 0.5% (pH 6.9) 15 minutes prior to incision. Group 3 received wound infiltration with a similar solution at the end of surgery. Anesthesia was induced with thiopental 3.0 mg/kg i.v., droperidol 50 micrograms/kg i.v., and sufentanil 0.5 microgram/kg i.v. and maintained with nitrous oxide 67% in oxygen and sufentanil 0.1 microgram/kg IV boluses as required. Postoperative pain was treated with morphine via a patient-controlled analgesia delivery system for 24 hours, followed by oral hydrocodone for 3 days. MEASUREMENTS AND MAIN RESULTS: The opioid consumption was recorded for 4 days postoperatively. Pain scores were measured at 4 to 8-hour intervals using 100 mm visual analog scales. There was no difference in either the opioid analgesic requirements or the pain scores between the three study groups. CONCLUSIONS: Wound infiltration, either preincision or postincision, had no clinically significant effect on the pain scores or analgesic requirements following abdominal hysterectomy.

[Difficult intubation: nasotracheal tube cuff inflation as an aid to difficult intubation]. / Intubation difficile: aide apportée par le gonflement du ballonnet de la sonde d'intubation nasotrachéale.

A case is reported of an unexpected difficult nasotracheal intubation for respiratory distress syndrome in a 72-yr-old obese woman with chronic obstructive pulmonary disease. After positioning the tip of the tracheal tube in the oropharynx, direct laryngoscopy did not allow exposure neither of the glottis nor of the corniculate cartilages. Fibreoptic tracheal intubation was decided. While preparing fibreoptic instruments, an attempt at blind intubation was performed. The tracheal tube cuff was inflated with 15 mL of air and then advanced gently until slight resistance was felt as the inflated cuff made contact with the vocal cords. At that time it was deflated and the tracheal tube advanced into the trachea. In the presence of normal pharyngeal anatomy, inflation of the tracheal tube cuff in the oropharynx is assumed to centre the tip of the tube and to direct it anteriorly towards the larynx. A recent prospective and randomized study has shown that tracheal tube cuff inflation in the oropharynx is effective in improving the success rate of blind nasotracheal intubation in paralysed patients with normal pharyngeal anatomy. Only case reports have shown the efficacy of tracheal tube cuff inflation in the pharynx as an aid to difficult blind nasotracheal intubation in emergency. Further controlled studies in this area would be valuable.

Tracheal tube cuff inflation as an aid to blind nasotracheal intubation.

We have assessed the efficacy of tracheal tube cuff inflation in the oropharynx as an aid to blind nasotracheal intubation in 20 ASA I and II patients undergoing elective oral surgery. The trachea was intubated once using the technique of tracheal tube cuff inflation in the oropharynx and once keeping the tracheal tube cuff deflated throughout the manoeuvre. With the cuff deflated, intubation was successful in nine of 20 (45%) patients; in eight of 20 (40%) it was successful on the first attempt. With the tracheal tube cuff inflated, intubation was successful in 19 of 20 patients (95%), 15 of 20 (75%) of these on the first attempt. The success rates were significantly different (P < 0.01). Times to intubate were not significantly different (P > 0.05). We conclude that, in normal patients, tracheal tube cuff inflation in the oropharynx increases the success rate of blind nasotracheal intubation.

Comparison of an ephedrine infusion with crystalloid administration for prevention of hypotension during spinal anesthesia.

This study was designed to compare the efficacy of an ephedrine infusion with crystalloid administration for reducing the incidence of hypotension during spinal anesthesia. Fifty-four ASA I patients scheduled for postpartum tubal ligations under spinal anesthesia were randomly allocated to receive either 15 mL/kg of crystalloid (crystalloid group) or an ephedrine infusion (infusion group). Spinal anesthesia was performed using 70-90 mg of hyperbaric 5% lidocaine. Patients in the infusion group immediately thereafter received an ephedrine infusion at a rate of 5 mg/min for the first 2 min and then 1 mg/min for the next 18 min. The incidence of hypotension was 15/27 (55%) in the crystalloid group and 6/27 (22%) in the infusion group (P < 0.05). There was no significant difference between the groups in relation to the level of anesthesia or maximal heart rate, and hypertension did not occur in either group. We conclude that a prophylactic ephedrine infusion is effective for minimizing and managing hypotension associated with spinal anesthesia and compares favorably with crystalloid administration in this patient population in terms of efficacy and incidence of side effects.