Tropisetron or droperidol in the prevention of postoperative nausea and vomiting

BACKGROUND: Women undergoing laparoscopic cholecystectomy are susceptible to postoperative nausea and vomiting (PONV). This study was undertaken to evaluate the efficacy of tropisetron or droperidol for preventing PONV after laparoscopic cholecystectomy. METHODS: In a prospective, randomised, double-blind trial, 120 female patients received either tropisetron 5 mg or droperidol 1.25 mg intravenously at the beginning of surgery. A standard general anaesthetic technique and postoperative analgesia were used. Nausea, emetic episodes and the need for rescue medication were recorded for 24 h postoperatively. RESULTS: Nausea was experienced by 55% of the patients in the tropisetron group and by 62% in the droperidol group (ns). The incidence of emetic episodes was 20% and 52% (P=0.001) in the two groups, respectively. Rescue antiemetic medication was needed in 42% and 50% (ns) of the patients, respectively. Patients in the droperidol group were more drowsy in comparison with patients in the tropisetron group, mean sedation score being 6.7 vs 5.7, respectively (P=0.023). No difference in other side-effects was observed. CONCLUSION: Tropisetron, when compared with droperidol, had no better efficacy on the prevention of postoperative nausea but resulted in a significantly lower incidence of vomiting after laparoscopic cholecystectomy.     

A comparison of the hemodynamic effects of paracervical block and epidural anesthesia for labor analgesia

BACKGROUND: Both paracervical block (PCB) and epidural analgesia are sometimes associated with hemodynamic effects potentially harmful to the well-being of the fetus. Our study was designed to test the hypothesis that PCB would have a more profound effect on maternal and fetal blood flow than epidural analgesia. METHODS: Forty-four healthy primiparous parturients were randomized to receive either PCB (n=21) or epidural analgesia (n= 23) with 25 or 30 mg of bupivacaine, respectively, for labor analgesia. Maternal blood pressure and fetal heart rate were recorded. Blood flow was measured using a color Doppler device. The blood flow measurements consisted of assessment of the pulsatility indices (PI) of the right maternal femoral artery and the main branch of the uterine artery (placental side), the umbilical artery and the fetal middle cerebral artery. The measurements were performed before administration of analgesia and approximately 15-20 min later after the onset of analgesia. RESULTS: Both methods provided in general good analgesia, but rescue medication was required more often after PCB. Epidural analgesia decreased maternal blood pressure more than PCB and the PI of maternal femoral artery decreased after onset of epidural analgesia, indicating epidural-induced vasodilation. The PI of the uterine artery increased after the onset of PCB, indicating vasoconstriction of this artery. No significant adverse effects or differences in the well-being of the newborn were observed, as indicated by similar Apgar scores and pH-status. CONCLUSION: There were small differences in the effects of PCB and epidural analgesia on uteroplacental circulation as well as on maternal hemodynamics. PCB may have a vasoconstrictive effect on the uterine artery. This and the fact that the parturients required rescue analgesia more frequently after PCB than after epidural block speaks for the feasibility of the latter in obstetrics.     

Growth of Escherichia coli in propofol, lidocaine, and mixtures of propofol and lidocaine

BACKGROUND: Microorganisms grow rapidly in propofol. Extrinsic contamination of propofol is thought to be a source of postoperative sepsis and wound infection. We studied growth of a strain of Escherichia coli in thiopental, propofol, lidocaine, and mixtures of propofol and lidocaine. METHODS: The pathogen was exposed to 2.5% thiopental; 1.0% propofol; 1.0%, 2.0% and 4.0% preservative-free lidocaine; and propofol solutions containing 0.25%, 0.5%, 1.0%, 2.0%, or 4.0% lidocaine for 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, and 24 h at room temperature, respectively. The inocula from these suspensions were cultured for 48 h at 37 degrees C after the antimicrobial activity of the local anesthetics in the inocula was inactivated by a 1:1000 dilution with distilled water. RESULTS: No organisms grew after exposure to 2.5% thiopental. The exposure of E. coli to propofol increased the colony count to approximately 90 times the control count. The colony counts of E. coli after exposure to 1.0%, 2.0% and 4.0% lidocaine and 0.25%, 0.5%, 1.0%, 2.0% and 4.0% lidocaine in 1.0% propofol were lower than the counts after exposure to 1.0% propofol (P = 0.0048, 0.0027, 0.0003, 0.0503, 0.0188, 0.0080, 0.0044, and 0.0001, respectively). The growth rate of the microorganism was significantly higher in cultures exposed to 1.0% propofol than that in cultures exposed to lidocaine alone or lidocaine-propofol mixtures (P < 0.0001, respectively). CONCLUSION: Lidocaine possesses bacteriostatic activity against E. coli. Addition of lidocaine to propofol confers its bacteriostatic activity to the mixture and may decrease the hazard of infection associated with the extrinsic contamination of propofol.     

Analgesia following paediatric day-surgical orchidopexy and herniotomy

We surveyed 90 boys, aged 1-13 years, who had undergone either orchidopexy or herniotomy, in a cohort study. Their pain and vomiting were assessed using a simple 4-point score in the Recovery Unit by the nursing staff, and at home by the parents. There were no significant differences in pain or vomiting scores between the two groups in the immediate postoperative period. However, children having orchidopexy experienced more pain at home during the first night and the following day than those having herniotomy. Nearly one-third of the former group had moderate to severe pain at home, in contrast to less than one-tenth of children having herniotomy, who are also more likely to be painfree on the next day. We concluded that children having herniotomy can be treated adequately at home with paracetamol alone, whereas children having orchidopexy may require supplementation with stronger analgesics.     

Radiological and clinical distribution of thoracic paravertebral blockade in infants and children

The radiological distribution of thoracic paravertebral blockade was studied by chest radiographs with radio-opaque dye injection in 18 paediatric patients. Two distinct patterns of distribution were found: longitudinal and cloudlike. Linear regression analysis found a strong correlation between the relative injected volume of radio-opaque dye and the number of covered segments for the longitudinal group (r= 0.92; number of segments = 3.19 + 14.49 × ml·kg^?1) whereas a moderate correlation was found for the cloudlike group (r= 0.47; number of segments = 3.27 + 3.21 × ml·kg^?1). An injected volume of 0.25 (SD 0.12) ml·kg^?1 of radio-opaque dye was found to cover 5.7 (SD 1.6) segments. In no case could spread to the extradural space be found. The clinical distribution of the blocks was examined in a small number of patients and was found to extend from dematome Th 3/4 to Th 12. An initial bolus dose of 0.5 ml·kg^?1 of the local anaesthetic solution is advocated in order to cover reliably at least five segments which would be sufficient in most clinical situations.     

The effects of tramadol on postoperative nausea, vomiting and headache after ENT surgery. A placebo-controlled comparison with equipotent doses of nalbuphine and pethidine

Background: Opioids given as adjuncts to balanced inhalational anaesthesia augment postoperative nausea and vomiting (PONV). Tramadol, equipotent to pethidine, does not depress respiration, but can cause an increase in blood pressure and headache via its monoaminergic actions. Nalbuphine, ten times as potent as pethidine, has a ceiling respiratory depressant and ceiling analgesic effect at >0.3 mg · kg^?1. We compared the effects of equipotent doses of tramadol and nalbuphine (3.0 and 0.3 mg · kg^?1, respectively) given as analgesic with induction of anaesthesia on emesis during recovery from anaesthesia and on PONV and headache until 24 h after ENT surgery, using saline (0.2 ml · kg^?1) and an equipotent dose of pethidine (1.5 mg · kg^?1) as controls. Method: The study population (N=281) comprised 4 comparable subgroubs (N=69 to 71 each). Anaesthetic medications were standardised. Emesis during recovery from anaesthesia and nausea, vomiting, retching, headache and administrations of antiemetic and analgesics until 24 h after surgery were recorded. Results: Emesis and antiemetic requirements during recovery from anaesthesia were similar and infrequent in each group, as were the incidences of nausea alone (3 to 5%), vomiting alone (17 to 31%), and nausea with vomiting (10 to 22%) during the first 24 h after surgery. However, any complaint of PONV was least frequent in the saline and pethidine groups (32% and 37%, respectively) and most frequent in the tramadol and nalbuphine groups (49% and 52%, respectively; P<0.05 versus saline, both comparisons; P=NS versus pethidine, both comparisons). The times to onset and severity of PONV were similar in each group, but patients given nalbuphine most frequently (P<0.025) needed rescue antiemetic to treat PONV. Headache occurred with similar frequency in each group. Conclusion: It is concluded that tramadol, nalbuphine and pethidine have similar emetic effect in the doses and manner used, and that tramadol does not increase the incidence of postoperative headache when used as peroperative analgesic.     

Total knee replacement: a comparison of ropivacaine and bupivacaine in combined femoral and sciatic block

BACKGROUND: Femoral and sciatic nerve block may improve post-operative analgesia following total knee replacement. OBJECTIVES: To compare the post-operative analgesia following primary total knee replacement provided by spinal anaesthesia alone or in combination with femoral and sciatic nerve block with bupivacaine or ropivacaine. METHODS: Seventy-five patients were randomised into one of three groups: spinal anaesthesia only; spinal anaesthesia and combined femoral and sciatic nerve block with 1 mg x kg(-1) bupivacaine 7.5 mg x ml(-1) to each nerve; spinal anaesthesia and combined femoral and sciatic nerve block with 1 mg x kg(-1) ropivacaine 7.5 mg x ml(-1) to each nerve. RESULTS: The mean (SD) time to first morphine request was significantly prolonged for both groups receiving combined femoral and sciatic block, 912 (489) min for the bupivacaine group and 781 (394) min for the ropivacaine group (P<0.001) compared with 413 (208) min for the group receiving spinal anaesthesia alone. Morphine consumption was significantly reduced in both groups receiving combined femoral and sciatic block. There were no systemic or neurological sequelae in any of the groups. CONCLUSIONS: Femoral and sciatic blockade following intrathecal bupivacaine/diamorphine provided superior analgesia when compared with intrathecal bupivacaine/diamorphine alone. There were no significant clinical differences between the group receiving bupivacaine 7.5 mg x ml(-1) and the group receiving ropivacaine 7.5 mg x ml(-1).     

A comparison of coracoid and axillary approaches to the brachial plexus

BACKGROUND: Brachial plexus block by the coracoid approach does not require arm abduction and may be more effective than the axillary approach because of a more proximal injection of local anaesthetic. However, the clinical usefulness of the coracoid approach has not been tested in prospective controlled trials. The present randomized, observer-blinded study compared success rates, time to obtain a complete block, frequency of adverse effects and block discomfort in two groups of 30 patients, anaesthetized for hand surgery using either the coracoid or the axillary approach to the brachial plexus. METHODS: After subcutaneous infiltration with 5 ml of 1% mepivacaine/adrenaline the brachial plexus was located using a nerve stimulator and an insulated pencil-point needle. Ropivacaine 0.75%, 20-40 ml, depending on body weight, was used for the initial block. In the coracoid (C) group two plexus cords, and in the axillary (A) group four terminal nerves were electrolocated and the volume of ropivacaine was divided equally between them. Spread of analgesia to the arm was assessed every 5 min, by an anaesthetist unaware of the block technique. The block was defined as effective (complete) when analgesia was present in all five sensory nerve areas distal to the elbow. Incomplete blocks were supplemented 30 min after the initial block. RESULTS: In the C group a median 11 min was required for block performance as compared to 12 min in the A group (NS). Onset of block was shorter and the frequency of incomplete blocks lower in the A group (median 17 min and 17%) than in the C group (30 min and 47%, respectively). Lack of analgesia of the ulnar nerve was the main cause of incomplete initial blocks in the C group. All incomplete blocks were successfully supplemented. However, total time to obtain complete block was shorter in the A group than in the C group (29 min vs. 41 min, P<0.05). Accidental arterial puncture occurred in seven patients (five in C and two in A group), which resulted in two haematomas, both in the C group (NS). No permanent sequelae were observed. CONLCUSION: The axillary approach to the brachial plexus using four injections of ropivacaine results in a faster onset of block and a better spread of analgesia than the coracoid approach using two injections.     

Anaesthesia, recovery and postoperative nausea and vomiting after breast surgery. A comparison between desflurane, sevoflurane and isoflurane anaesthesia

BACKGROUND: Whereas induction and recovery will occur more rapidly with the new low soluble anaesthetics than with isoflurane, the quality of anaesthesia and recovery with special emphasis on postoperative nausea and vomiting (PONV) is not well known. METHODS: In an open (peroperatively), double-blinded (postoperatively), randomised controlled study, we assessed anaesthesia characteristics, recovery and 24 h PONV after breast surgery comparing isoflurane, desflurane and sevoflurane. RESULTS: There were no significant quality differences between the three agents during anaesthesia and recovery except for the incidence of PONV in the postanaesthesia care unit (PACU). The PONV rate (24 h in PACU and ward) was higher in the desflurane group (67%) than in the isoflurane group (22%), (P<0.01). The corresponding PONV rate for sevoflurane was 36%. CONCLUSION: The quality of anaesthesia, time to opening of eyes and influence on respiration was similar with all three anaesthetics. As the emergence from anaesthesia did not differ significantly between the three agents, the choice of agent could be based on PONV rate and price. Desflurane had a significantly higher 24 h PONV rate than isoflurane. Early PACU PONV rate was significantly (P<0.05) lower for the more soluble isoflurane (4%) than for the low soluble gases, desflurane and sevoflurane together (28%). The result of this study does not give a rationale for a transition to the new low soluble agents in breast cancer surgery.     

Combination of intra-articular tenoxicam, lidocaine, and pethidine for outpatient knee arthroscopy

BACKGROUND: Studies of intra-articular non-steroidal anti-inflammatory drugs have revealed an analgesic effect equivalent to that of intra-articular local anaesthetic agents and morphine. The aim of this study was to evaluate the analgesic effect of intra-articular lidocaine, pethidine and tenoxicam compared with that of lidocaine and pethidine on postoperative pain after arthroscopy. METHODS: After day-case knee arthroscopy, 60 patients were randomly allocated to one of three groups to receive 20 ml of a solution containing 0.9% saline (group S), 2% lidocaine and 10 mg preservative-free pethidine (group LP) and 2% lidocaine, 10 mg preservative-free pethidine and 20 mg tenoxicam (group LPT). Postoperative pain was assessed using a visual analogue scale and measuring analgesic requirements. RESULTS: Pain scores were significantly lower in the LP group than in the S group at 1 and 2 h after surgery. From 4 h until the end of the first postoperative day, pain scores were significantly lower in the LPT group of patients at rest and on knee flexion than in the other two groups; these patients also used less oral analgesics (P<0.05). CONCLUSION: The combination of 20 ml lidocaine 2%, 10 mg pethidine and 20 mg tenoxicam given intra-articularly provided superior analgesia and reduced oral analgesic requirement during the first day after arthroscopy compared with lidocaine and pethidine alone.     

Marked enhancement of anti-allodynic effect by combined intrathecal administration of the adenosine A1-receptor agonist R-phenylisopropyladenosine and morphine in a rat model of central pain

BACKGROUND: There is often no satisfactory treatment for chronic pain after spinal cord injury. We have previously reported that intrathecal (i.t.) administration of the adenosine A1-receptor agonist R-phenylisopropyl-adenosine (R-PIA) or the opioid morphine has anti-allodynic effects in a model of presumed chronic central pain after photochemically induced spinal cord injury in rats. In the present study, we set out to investigate the possible interaction between i.t. R-PIA and morphine in spinally injured rats. METHODS: Sprague-Dawley rats displaying allodynia-like behaviors to mechanical and cold stimuli after photochemically induced spinal cord injury with minor motor deficits were used. R-PIA and morphine, either alone or in combination, were administered i.t. through an implanted catheter to lumbar spinal cord. RESULTS: Cumulative doses of R-PIA or morphine dose-dependently reduced the mechanical allodynia-like behavior, with a threshold of 1 nmol and 1.5 nmol, respectively. When co-administrated, R-PIA and morphine produced marked suppression of mechanical allodynia at doses of 5 pmol and 7.5 pmol, respectively. The effect of i.t. co-administration of R-PIA and morphine on cold allodynia was comparable to i.t. R-PIA alone. The combination of R-PIA and morphine did not increase adverse effects such as motor deficits in comparison to either drug alone. CONCLUSION: These results demonstrate a supra-additive interaction between the adenosine A1-receptor agonist R-PIA and morphine to reduce mechanical allodynia-like behavior in rats with chronic spinal cord injury. The combination of R-PIA and morphine administered spinally may be superior to R-PIA or morphine alone for treating such pain.     

Efficacy and safety of premedication with oral ketamine for day-case adenoidectomy compared with rectal diazepam/diclofenac and EMLA

BACKGROUND: Because of its pain-attenuating and sedative properties oral ketamine has been used as premedication in children and adults. We wanted to compare in children scheduled for adenoidectomy safety and efficacy of oral ketamine with a premedication that causes similar preoperative sedation and relief of pain at the venepuncture site. We also evaluated the effect of i.v. glycopyrrolate added to these combinations. METHODS: One hundred children between 10 and 15 kg of body weight scheduled for day-case adenoidectomy were randomly assigned to one of four groups: groups DG and DS received diclofenac 12.5 mg and diazepam 0.5 mg/kg rectally, EMLA cream at the venepuncture site, and placebo orally; groups KG and KS received ketamine 6.0 mg/kg orally, placebo cream at the puncture site, and placebo rectally; additionally, groups DG and KG received glycopyrrolate 5 microg/kg, and groups DS and KS received placebo intravenously. We recorded perioperatively scores (open scale 1-9) for stridor, sedation, bleeding, nausea, pain, heart rate, the need for analgesics and registered psychotomimesis and well-being at home. RESULTS: The children of the K-groups became more tearful during separation from their parents (P=0.0072). No other differences were found between the ketamine and diazepam/diclofenac groups before and after premedication until induction of anaesthesia. Oral ketamine produced unpleasant psychotomimesis in four out of 59 children. During the first 10 min postoperatively, the score for stridor was significantly higher in group KS than in the D-groups; stridor scores > or = 6 were seen in one child of the D-groups (DS) and in six children of the K-groups (n.s.), of whom three developed laryngospasm (one reintubation). Glycopyrrolate diminished salivation in all groups, but had no effect on stridor scores. Additionally, glycopyrrolate delayed the onset of eating at home. CONCLUSION: Premedication with racemic oral ketamine 6 mg/kg does not seem to be suitable for upper airway procedures. Addition of i.v. glycopyrrolate before the induction of anaesthesia significantly reduced the scores for salivation.     

Comparison of transarterial and multiple nerve stimulation techniques for axillary block using a high dose of mepivacaine with adrenaline

BACKGROUND: High-dose transarterial (TA) technique results in high effectiveness of the axillary block. The technique is fast and simple, but does not produce a satisfactory success rate when using the manufacturer's recommended dose of mepivacaine. The multiple nerve stimulation (MNS) technique requires more time and experience. This double-blind study compared effectiveness, safety and the time used to obtain an effective analgesia in 101 patients, having an axillary block by either TA or MNS techniques. METHODS: Mepivacaine with adrenaline (MEPA), 850 mg, was used for the initial block. Five millilitres of 1% solution was injected subcutaneously. In the TA group, 20 mL of 2% solution was injected deep to, and 20 mL superficial to the axillary artery. In the MNS group, four terminal motor nerves were electrolocated in the axilla, and injected with 10 mL each. Analgesia was assessed every 10 min and, when needed, supplemented after 30 min. The block was effective when analgesia was present in all sensory nerve areas distal to the elbow. RESULTS: The MNS group required median 11 min for block performance compared with 8 min for the TA group (P < 0.001). Latency of the initial block was shorter and the frequency of supplemental analgesia lower in the MNS group (median 10 min and 6%) than in the TA group (30 min and 36%, respectively), P < 0.001. All incomplete blocks were successfully supplemented. However, the total time to obtain an effective block was shorter in the MNS group (23 min) than in the TA group (37 min), P < 0.001. Two patients in each group had signs and symptoms of systemic toxicity, the most serious being atrial fibrillation and temporary loss of consciousness in a cardiovascularly medicated patient. The local adverse effects (intravascular injections and haematomas) were fewer in the MNS group, P < 0.001. CONCLUSION: The MNS technique of axillary block by four injections of 10 mL of 2% MEPA produces faster and more extensive block than the TA technique by two injections of 20 mL. Therefore, the MNS technique requires fewer supplementary blocks and results in faster patient readiness for surgery. However, high doses of MEPA may result in dangerous systemic toxic reactions.     

Effect of intra-operative magnesium sulphate on pain relief and patient comfort after major lumbar orthopaedic surgery

The effects of intra-operative magnesium sulphate on pain relief after major lumbar surgery were investigated in 24 patients. Patients were randomly allocated to receive either an infusion of 50 mg x kg(-1) magnesium sulphate or an equivalent volume of saline at induction of anaesthesia. Anaesthesia was induced with propofol and remifentanil. Tracheal intubation was facilitated using rocuronium. Maintenance was achieved with remifentanil and sevoflurane in nitrous oxide/ oxygen. Intra-operative monitoring included standard equipment and neuromuscular transmission. During surgery, neuromuscular block recovery was longer in the magnesium group. Postoperative opioid consumption and pain scores were lower in the magnesium group. The first night's sleep and the global satisfaction scores were better in the magnesium group. The results of the study support magnesium sulphate as a useful adjuvant for postoperative analgesia after major lumbar surgery.     

The effect of ketamine on clinical endpoints of hypnosis and EEG variables during propofol infusion

BACKGROUND: We studied the effect of variable doses of ketamine on the endpoints of hypnosis, e.g., unresponsiveness to verbal commands (UVC), loss of eyelash reflex (LER), and inhibition of body movement response with or without sneezing to nasal membrane stimulation (INBMR), and processed EEG variables, e.g., bispectral index (BIS), 95% spectral edge frequency (SEF) and median frequency (MF) during propofol infusion. METHODS: Forty-eight patients received either propofol infusion, 30 mg.kg-1.h-1 (Group P; n = 12) or ketamine bolus, 0.25, 0.5 or 0.75 mg i.v., followed by propofol infusion, 30 mg.kg-1.h-1 + variable dose ketamine infusion, 0.25, 0.5 or 0.75 mg.kg-1.h-1 (Groups PK0.25, PK0.5 and PK0.75; n = 12 each) until UVC, LER and INBMR. BIS, 95% SEF and MF values were monitored and recorded at the endpoints of hypnosis. Propofol and ketamine concentrations were measured at INBMR. RESULTS: Propofol infusion, 30 mg.kg-1.h-1, induced UVC, LER and INBMR at BIS: 65 +/- 2, 63 +/- 9 and 33 +/- 7; 95% SEF: 17 +/- 3, 17 +/- 4 and 14 +/- 3; and MF values of 5 +/- 2, 5 +/- 3 and 3 +/- 2, respectively. With adjunctive ketamine (Groups PK0.5 and PK0.75), the hypnotic endpoints were achieved at higher BIS and 95% SEF values and lower propofol doses and concentrations as compared to Groups P and PK0.25 (9.9 +/- 5.8 and 9.4 +/- 3.4 vs. 13.4 +/- 4.5 and 14 +/- 5.8 micrograms.ml-1). CONCLUSIONS: Our results suggest additive interaction between propofol and ketamine (Groups PK0.5 and PK0.75) for achieving the hypnotic endpoints; however, ketamine did not depress the EEG variables in proportion to its hypnotic effect. The paradoxically higher BIS and 95% SEF values at the hypnotic endpoints may be due to lower propofol concentrations and/or no effect of ketamine on the EEG variables.     

Droperidol decreases the incidence and the severity of vomiting after tonsillectomy and adenoidectomy in children

We assessed the effect of intravenous droperidol on the incidence and the severity of postoperative vomiting in children undergoing tonsillectomy and adenoidectomy. Seventy-nine ASA physical status I or II children aged 1.5 to 18 years (mean 6.1 years) were randomized into two groups. Group I received droperidol 50 μg·kg^?1 i.v. (maximum 1.25 mg), while group II received saline placebo immediately following the induction of general anaesthesia. All episodes of vomiting were recorded from the time of extubation until discharge the next morning. Of the 35 assigned to group I only 16 (46%) had one or more episodes of emesis compared to 31 of 44 (71%) in group II (P < 0.05). Patients in group I who vomited, did so only 1.9 ± 1.2 times compared to 4.6 ± 3.8 times for the control patients (P < 0.01). The authors conclude that droperidol at a dose of 50 μg·kg^?1 given at the time of induction of anaesthesia to healthy children decreases the incidence and the severity of vomiting during the first postoperative day following tonsillectomy and adenoidectomy.;