Comparison of etomidate and methohexital as anesthetic agents for continuation and maintenance electroconvulsive therapy: A retrospective analysis of seizure quality and safety.

BACKGROUND: The ideal hypnotic agent for electroconvulsive therapy (ECT) is still under debate and previous studies comparing etomidate and methohexital have produced conflicting results. This retrospective study compares etomidate and methohexital as anesthetic agents in continuation and maintenance (m)ECT with regard to seizure quality and anesthetic outcomes. METHODS: All subjects undergoing mECT at our department between October 1st, 2014 and February 28th, 2022 were included in this retrospective analysis. Data for each ECT session were obtained from the electronic health records. Anesthesia was performed with either methohexital/succinylcholine or etomidate/succinylcholine. Standard seizure quality parameters, anesthesiological monitoring data, pharmacological interventions and side-effects were recorded. RESULTS: 573 mECT treatments in 88 patients were included (methohexital n = 458, etomidate n = 115). Seizures lasted significantly longer after using etomidate (electroencephalography: +12.80 s [95 %-CI:8.64-16.95]; electromyogram +6.59 s [95 %-CI:4.14-9.04]). Time to maximum coherence was significantly longer with etomidate (+7.34 s [95 %-CI:3.97-10.71]. Use of etomidate was associated with longer procedure duration (+6.51 min [95 %-CI:4.84-8.17]) and higher maximum postictal systolic blood pressure (+13.64 mmHg [95 %-CI:9.33-17.94]). Postictal systolic blood pressure > 180 mmHg, the use of antihypertensives, benzodiazepines and clonidine (for postictal agitation), as well as the occurrence of myoclonus was significantly more common under etomidate. CONCLUSIONS: Due to longer procedure duration and an unfavorable side effect profile, etomidate appears inferior to methohexital as an anesthetic agent in mECT despite longer seizure durations.

Extended-release opioids in the management of cancer pain: a systematic review of efficacy and safety.

Despite the increased availability of strong analgesics and evidence-based recommendations for pain management, under-treatment of cancer-related pain is still common. Extended-release (ER) opioids, in contrast to immediate-release opioids, provide prolonged analgesia. In this review, we aimed to compare the efficacy and safety of ER opioid analgesics in managing moderate-to-severe pain in patients with cancer. We identified randomized controlled trials (RCTs) and controlled observational studies that compared ER opioids in cancer pain by searching several databases, including MEDLINE, EMBASE and the Cochrane Library. Two independent reviewers screened and evaluated retrieved records to select relevant studies. We dually assessed the risk of bias for included studies and evaluated the overall strength of evidence for six critical outcomes using Grading of Recommendations Assessment, Development and Evaluation level of evidence. A total of three double-blind RCTs (comparative efficacy and adverse events), two non-blinded RCTs and four observational studies (comparative adverse events) were included in this review. All randomized trials and one observational study were of high risk of bias, and three observational studies of unclear risk of bias. The level of evidence for the selected efficacy and safety outcomes was low and very low. We synthesized the findings qualitatively because of the paucity of relevant studies as well as variable study design and quality. This systematic review indicates no substantial differences in efficacy and frequent adverse events among ER opioids for cancer pain. The body of evidence, however, is limited to few comparisons and fraught with methodological shortcomings.

Withdrawal forces of lumbar spinal catheters: no dependence on body position.

BACKGROUND: Spinal catheters, because of their smaller diameter, have lower tensile strength than epidural catheters. This study was designed to measure the withdrawal forces needed to remove lumbar spinal catheters and to determine whether patient position affects withdrawal forces. METHODS: Eighty-two patients with a 24-gauge spinal catheter placed midline at the lumbar L3/4 or L4/5 level were randomly assigned to catheter removal either in flexed lateral or sitting position. Withdrawal forces were measured using a tension spring balance. RESULTS: Mean withdrawal force was 0.91 N (95% CI: 0.73, 1.09) with extremes up to 5 N. Withdrawal force in the flexed lateral position was 1.04 N (95% CI: 0.73, 1.34) or in the sitting position was 0.78 N (95% CI: 0.59, 0.97). The 95% CI for the difference of the means was -0.62 N, 0.10 N. Thus, the absolute mean difference between the positions can be assumed to be smaller than 0.62 N. Neither the length of the spinal catheter under the skin or in the subarachnoid space, nor BMI influenced withdrawal force. CONCLUSION: Withdrawal force of spinal catheters is not influenced by body position during catheter removal, length of catheter under skin, or BMI.

Effects of SZ1677, a new non-depolarizing steroidal neuromuscular blocking drug, and rocuronium on two laryngeal muscles and the anterior tibial muscle in guinea pigs.

BACKGROUND: SZ1677 is a new neuromuscular blocking drug structurally related to rocuronium. We compared the effect of an ED(90) of SZ1677 (25 microg/kg) with that of rocuronium (100 microg/kg) in guinea pig laryngeal and peripheral muscles. METHODS: Electromyography was used to quantify neuromuscular blockade at the posterior cricoarytenoid muscle, the thyroarytenoid muscle and the anterior tibial muscle after SZ1677 (n = 10) and rocuronium (n = 9). RESULTS: Maximum neuromuscular blockade was similar after SZ1677 and rocuronium (83 +/- 11% vs. 89 +/- 11%; thyroarytenoid muscle: 91 +/- 8% vs. 97 +/- 3%; anterior tibial muscle: 91 +/- 15% vs. 96 +/- 3%, respectively). Onset time of neuromuscular blockade at the laryngeal muscles was similar for the two neuromuscular blocking drugs; it was shorter at the thyroarytenoid muscle (67 +/- 32 s vs. 42 +/- 40 s) than at the posterior cricoarytenoid muscle (101 +/- 26 s vs. 102 +/- 108 s). Onset time at the anterior tibial muscle was longer after SZ1677 (114 +/- 34 s) than after rocuronium (68 +/- 46 s); P < 0.05. Neuromuscular recovery was faster after SZ1677 (interval 25%-75%: posterior cricoarytenoid muscle: 222 +/- 66 s; thyroarytenoid muscle: 192 +/- 92 s; tibial muscle 149 +/- 55 s) than after rocuronium (450 +/- 148 and 464 +/- 183 s, 292 +/- 86 s, respectively); P < 0.05. CONCLUSIONS: In guinea pigs, SZ1677 offers a rapid onset of neuromuscular blockade at a laryngeal adductor muscle with a shorter duration than rocuronium. Regardless of the drug used, the course of neuromuscular blockade differs not only between peripheral muscles and the larynx but also between antagonistic laryngeal muscles. The differences seem to be species specific.

Sevoflurane and propofol decrease intraocular pressure equally during non-ophthalmic surgery and recovery.

BACKGROUND: To provide good control of intraocular pressure (IOP) during anaesthesia and surgery, we conducted a study comparing the effects on IOP during maintenance and recovery of sevoflurane vs propofol anaesthesia in 33 patients (ASA I-II) undergoing elective non- ophthalmic surgery. METHODS: Anaesthesia was induced with propofol 2 mg kg(-1), fentanyl 2 micro g kg(-1) and vecuronium 0.1 mg kg(-1). Patients were allocated randomly to receive either propofol 4-8 mg kg(-1) h(-1) (group P; n=16) or 1.5-2.5 vol% sevoflurane (group S; n=17) for maintenance of anaesthesia. Fentanyl 2-4 micro g kg(-1) was added if necessary. The lungs were ventilated with 50% air in oxygen. Blood pressure, heart rate, oxygen saturation and end-tidal carbon dioxide were measured before and throughout anaesthesia and in the recovery room. IOP was determined with applanation tonometry (Perkins) by one ophthalmologist blinded to the anaesthetic technique. RESULTS: There was a significant decrease in IOP after induction and during maintenance of anaesthesia in both groups. No significant differences in IOP between the two groups was found. CONCLUSION: Sevoflurane maintains the IOP at an equally reduced level compared with propofol.

Effects of vecuronium and rocuronium in antagonistic laryngeal muscles and the anterior tibial muscle in the cat.

BACKGROUND: Adequate vocal cord paralysis and full recovery of laryngeal muscle function are important when muscle relaxants are used perioperatively. This study was designed to compare the effects of vecuronium and rocuronium at the vocal cord abductor and adductor muscles and the anterior tibial muscle in cats. METHODS: Twelve adult cats were studied under pentobarbitone-N2O/O2-anesthesia. After supramaximal electrical stimulation of the peroneal nerve and the recurrent laryngeal nerve (0.1 Hz and intermittent train-of-four) evoked electromyographic responses were obtained from the anterior tibial muscle, the posterior cricoarytenoid muscle (vocal cord abductor) and two vocal cord adductor muscles, the lateral cricoarytenoid and the vocal muscle. Six cats received bolus doses of increasing size of vecuronium (ED90 22.5 microg x kg(-1)) and six cats rocuronium (ED90 90 microg x kg(-1)). RESULTS: Equipotent doses of vecuronium and rocuronium caused a similar degree of paralysis in all muscles (vecuronium ED90: 70% blockade at the posterior cricoarytenoid, 83% at the lateral cricoarytenoid, 84% at the vocal muscle and 90% at the anterior tibial muscle; rocuronium ED90: 71% at the posterior cricoarytenoid, 67% at the lateral cricoarytenoid, 78% at the vocal muscle and 90% at the anterior tibial muscle; vecuronium 2 x ED90: 93% blockade at the posterior cricoarytenoid, 95% at the lateral cricoarytenoid, 97% at the vocal muscle and 99% at the anterior tibial muscle; rocuronium 2 x ED90: 89% blockade at the posterior and lateral cricoarytenoid, 93% at the vocal muscle and 100% at the anterior tibial muscle). Onset time was significantly shorter at the posterior cricoarytenoid muscle (290 s) compared to the lateral cricoarytenoid muscle (400 s) after vecuronium ED90 and to the vocal muscle (150 s versus 210 s) after rocuronium ED90. Compared to the anterior tibial muscle (interval 25-75%: 6.5 min after vecuronium 2 x ED90 and 3.3 min after rocuronium 2 x ED90 and to the posterior cricoarytenoid muscle (interval 25-75%: 7 min after vecuronium 2 x ED90 and 4.3 min after rocuronium 2 x ED90), recovery of laryngeal adductor muscle function was markedly delayed with both neuromuscular blocking drugs (interval 25-75% at the lateral cricoarytenoid and vocal muscle: 14 min and 15.8 min after vecuronium 2 x ED90 and 10.3 min and 11.6 min after rocuronium 2 x ED90 respectively). CONCLUSION: In cats, the time course of neuromuscular blockade after vecuronium and rocuronium differs in antagonistic laryngeal muscles. The protective laryngeal function of glottis closure recovers later than vocal cord abduction after both vecuronium and rocuronium.

Sevoflurane anaesthesia in paediatric patients: better than halothane?

Forty-two children (aged 2-16 years) were randomly assigned to receive either sevoflurane (n = 21) or halothane (n = 21) in nitrous oxide/oxygen. After pre-medication with midazolam, anaesthesia was induced by facemask and the anaesthetic concentration was increased until loss of eyelash reflex (sevoflurane, 6%; halothane, 2.5%). Thereafter, 1-1.5 MAC of the inhalational agents were maintained until skin closure. Intra-operative analgesia was provided either by intermittent intravenous (i.v.) bolus doses of fentanyl (2-3 micrograms kg-1) or by a regional blockade. Induction was smooth and the time to loss of eyelash reflex was slightly shorter with sevoflurane than with halothane, the difference not quite reaching statistical significance (P = 0.06). In both groups, heart rate remained stable and blood pressure decreased significantly during induction. Haemodynamic parameters remained stable during anaesthetic maintenance; no cardiac dysrhythmias were observed. Emergence time with sevoflurane was 12.9 min vs. 16.3 min with halothane, but this difference was not statistically significant. It is concluded that sevoflurane is as suitable for paediatric patients as halothane. The slightly faster emergence time offered by sevoflurane over halothane was of no clinical significance in the present study.

The efficacy and safety of a clonidine/bupivacaine combination in caudal blockade for pediatric hernia repair.

UNLABELLED: We evaluated the analgesic efficacy and hemodynamic and respiratory safety of clonidine when added to bupivacaine for caudal blocks in 58 children aged 38 +/- 2 mo (mean +/- SEM). Patients scheduled for ambulatory hernia repair were randomly given a caudal injection (0.75 mL/kg) of either saline placebo (P group), bupivacaine, 0.25% (B group), bupivacaine plus epinephrine 1:200,000 (BE group), bupivacaine plus clonidine 1 microgram/kg (BC1 group), or bupivacaine plus clonidine 2 micrograms/kg (BC2 group). Postoperative measurements included duration of analgesia, hemodynamics, and respiratory monitoring for 6 h. Thereafter, parents assessed their child's analgesic requirements at home every 3 h for 18 h. The duration of analgesia (median [range]) was significantly longer (P < 0.05) in the BC1 and BC2 groups (360 [270-360] min and 360 [355-360] min, respectively) compared with the P (77[45-190]), B (346[105-360]), or BE group (300[75-360]). Similarly, the BC1 and BC2 groups required less additional analgesic within the first 24 h. All groups showed a significant decrease in mean arterial pressure compared with baseline values, but the differences among the groups were not significant. Bradycardia and respiratory depression were not observed. Clonidine 1 and 2 micrograms/kg can be safely added to bupivacaine caudal blockade in small children for ambulatory hernia repair to achieve an increased duration of analgesia compared with bupivacaine alone or bupivacaine plus epinephrine. IMPLICATIONS: The addition of clonidine, an antihypertensive drug with analgesic properties, to local anesthetics in caudal blocks prolongs postoperative pain relief and reduces the need for additional pain treatment in children after hernia operation.

The cerebral and cardiovascular effects of cisatracurium and atracurium in neurosurgical patients.

UNLABELLED: Drugs for neurosurgical patients should not increase intracranial pressure (ICP) or change cerebral perfusion pressure (CPP) and cerebral blood flow. This double-blind, cross-over study compares the effects of a single (3 x effective dose producing 95% twitch depression) intravenous bolus dose of cisatracurium 0.15 mg/kg with atracurium 0.75 mg/kg on mean red blood cell flow velocity in the middle cerebral artery (CBFV; transcranial Doppler), ICP (intraventricular or intraparenchymal monitor), mean arterial pressure (MAP), CPP (MAP-ICP), and heart rate (HR) every minute during a 15-min study period. Included in the study were 14 sedated and ventilated adult neurosurgical patients. After the cisatracurium bolus, ICP, CPP, CBFV, MAP, and HR did not change, and no histamine related events were observed. After the atracurium bolus, ICP, CPP, CBFV, and MAP decreased. The lowest values of ICP (-16% of baseline), CPP (-5%), CBFV (-8%), and MAP (-7%) were recorded 2-4 min after the atracurium bolus injection. After this transient decrease, MAP and CPP returned to baseline, whereas CBFV and ICP transiently exceeded baseline values. The highest values of CBFV (5%) and ICP (17%) were recorded 9-12 min after the atracurium bolus injection. Five patients showed a typical histamine response after atracurium, with a decrease in MAP and flushing. Excluding these five patients eliminated statistical significance in ICP, CPP, CBFV, and MAP differences. In conclusion, cisatracurium demonstrated fewer cerebral and cardiovascular hemodynamic side effects in sedated adult neurosurgical patients. IMPLICATIONS: This double-blind study in sedated and mechanically ventilated adult neurosurgical patients demonstrates that an intravenous bolus dose of the neuromuscular blocker cisatracurium results in less cerebral (intracranial pressure, cerebral perfusion pressure, middle cerebral artery blood flow velocity) and cardiovascular (blood pressure) hemodynamic side effects, compared with an equipotent dose of atracurium.

[Regional anesthetic procedures in pediatric anesthesia]. / Regionalanästhesiologische Verfahren im Konzept der Kinderanästhesie.

Regional anaesthetic procedures are not popular in paediatric anaesthesia in many institutions. However, regional anaesthesia is gaining ground, especially in a "new" concept of balanced paediatric anaesthesia. The decisive argument for the use of regional anaesthesia is the prolongation of pain relief further into the postoperative phase. The minimal haemodynamic and respiratory side effects during epidural and spinal anaesthesia, the reduced narcotic requirement and the potential early mobilisation all speak in favour of practical application of these techniques. Specially adapted needles and catheters have reduced the technical limitations. The use of nerve stimulators has optimize the accuracy of needle and catheter positioning. The use of a nerve stimulator is therefore highly recommended for peripheral nerve blocks in children. On the other hand, the use of regional anaesthesia in children has potential disadvantages, which should be considered. Special knowledge and continuous training are required. Many techniques are time consuming and personnel intensive, at least temporarily, and the combination of general and regional anesthesia exposes the child to the potential risk inherent in both procedures. The aim of this paper is to discuss procedures which have gained favour in paediatric regional anaesthesia during the past few years. These include caudal, epidural and spinal anaesthesia, especially for infants with high narcotic risk, as well as fascia iliaca compartment blocks for lower extremity analgesia and penile blocks. Many peripheral nerve blocks require special experience and therefore are not discussed here, but they are used routinely by specialists in all age groups. Good anatomic and pharmacologic knowledge should be a prerequisite for all physicians who use regional anaesthetic procedures. Continuous training and critical analysis are needed for good results. Only then can such methods be introduced into routine paediatric anaesthetic practice.