Cold infusions alone are effective for induction of therapeutic hypothermia but do not keep patients cool after cardiac arrest

AIM OF THE STUDY

Cold infusions have proved to be effective for induction of therapeutic hypothermia after cardiac arrest but so far have not been used for hypothermia maintenance. This study investigates if hypothermia can be induced and maintained by repetitive infusions of cold fluids and muscle relaxants.

MATERIAL AND METHODS

Patients were eligible, if they had a cardiac arrest of presumed cardiac origin and no clinical signs of pulmonary oedema or severely reduced left ventricular function. Rocuronium (0.5 mg/kg bolus, 0.5 mg/kg/h for maintenance) and crystalloids (30 ml/kg/30 min for induction, 10 ml/kg every 6h for 24h maintenance) were administered via large bore peripheral venous cannulae. If patients failed to reach 33+/-1 degrees C bladder temperature within 60 min, endovascular cooling was applied.

RESULTS

Twenty patients with a mean age of 57 (+/-15) years and mean body mass index of 27 (+/-4)kg/m(2) were included (14 males). Mean temperature at initiation of cooling (median 27 (IQR 16; 87)min after admission) was 35.4 (+/-0.9) degrees C. In 13 patients (65%) the target temperature was reached within 60 min, 7 patients (35%) failed to reach the target temperature. Maintaining the target temperature was possible in three (15%) patients and no adverse events were observed.

CONCLUSION

Cold infusions are effective for induction of hypothermia after cardiac arrest, but for maintenance additional cooling techniques are necessary in most cases.

The actions of prostaglandins I2 and E2 on arrhythmias produced by coronary occlusion in the rat and dog

Prostaglandins E2 and I2 were compared with known antiarrhythmics for their actions against arrhythmias produced by occlusion of the left anterior descending coronary artery in the anaesthetised rat while PGI2 was also examined in the dog. PGI2 in the dog suppressed early arrhythmias produced during occlusion but did not influence those produced by occlusion-release or those occurring 24 hours after a permanent occlusion; none of the A,B,C or D series prostaglandins tested markedly reduced 24 hour arrhythmias. In the rat PGE2 was antiarrhythmic against early occlusion arrhythmias (30 minutes occlusion) in a dose related manner (infusions of 1-4 microgram/kg/min) whereas PGI2 infusions potentiated the arrhythmogenic effect of occlusion. PGE2 was as effective an antiarrhythmic as 10mg/kg Org. 6001 which was more effective in this test situtation than dl-propranolol. No obvious mechanisms for the actions of PGE2 or PGI2 were apparent although both agents lowered blood pressure and reduced the size of the occluded zone produced by ligation.

The Combitube as a salvage airway device for paramedic rapid sequence intubation

STUDY OBJECTIVE

The safety of out-of-hospital rapid sequence intubation depends on a reliable strategy when orotracheal intubation is unsuccessful. Here we describe our experience with the Combitube (esophageal-tracheal twin-lumen airway device) as a salvage airway device for paramedic rapid sequence intubation.

METHODS

The San Diego Paramedic Rapid Sequence Intubation Trial was performed to assess the effect of paramedic rapid sequence intubation on outcome in severely head-injured patients. Adults with severe head trauma (Glasgow Coma Scale score 3 to 8) who were unable to be intubated without medications were enrolled. Midazolam and succinylcholine were administered, and paramedics were allowed a maximum of 3 attempts at orotracheal intubation. If the attempts were unsuccessful, Combitube insertion was mandated. After confirmation of tube position, rocuronium was given and standard ventilation protocols were used. The primary outcome measure for this analysis was the success rate for Combitube insertion after unsuccessful orotracheal intubation. In addition, Combitube insertion and orotracheal intubation patients were compared with regard to demographic, clinical, and outcome data.

RESULTS

A total of 426 patients were enrolled in the trial, with 420 meeting inclusion criteria for this analysis. Orotracheal intubation was successful in 355 (84.5%) of 420; Combitube insertion was successful in 58 (95.1%) of 61 attempts, with no reported complications. Patients undergoing Combitube insertion had higher Face Abbreviated Injury Scale scores and were more likely to have oropharyngeal blood or vomitus. Arrival Pco(2) values were higher, and arrival Po(2) values were lower but still supranormal in patients undergoing Combitube insertion. There were no mortality differences between patients undergoing Combitube insertion and those undergoing orotracheal intubation.

CONCLUSION

The Combitube can be an effective salvage airway device for paramedic rapid sequence intubation in an urban/suburban, high-volume emergency medical services system with paramedics who are experienced in Combitube placement and with stringent protocols for its use. The device should be tested in other sizes and types of systems and under less medical scrutiny than was used in this study.

Newer neuromuscular blocking agents: how do they compare with established agents?

Rapacuronium bromide (rapacuronium; ORG-9487) is a nondepolarising muscle relaxant (NMBA) with a low potency [90% effective dose (ED90) 1 mg/kg], which to some extent is responsible for its rapid onset of action. Because of the high plasma clearance (5.3 to 11.1 mg/kg/min) of rapacuronium, its clinical duration of action following single bolus doses up to 2 mg/kg in adults is short (i.e. <20 minutes). Rapacuronium forms a pharmacologically active 3-desacetyl metabolite, ORG-9488, which may contribute to a delay in spontaneous recovery after repeat bolus doses or infusions. After rapacuronium 1.5 mg/kg clinically acceptable intubating conditions are achieved within 60 to 90 seconds in the majority of adult and elderly patients undergoing elective anaesthesia. However, in a rapid-sequence setting. intubating conditions are less favourable after rapacuronium 1.5 to 2.5 mg/kg than after succinylcholine. The most prominent adverse effects of rapacuronium (tachycardia, hypotension and bronchospasm) are dose-related, and in particular pulmonary adverse effects are observed more frequently under conditions of a rapid-sequence induction in adults. Therefore, it seems worthwhile to consider only doses of rapacuronium < or = 1.5 mg/kg to facilitate rapid tracheal intubation, and to use succinylcholine or rocuronium rather than rapacuronium in a rapid-sequence setting. Rapacuronium, however, is a suitable alternative to mivacurium chloride (mivacurium) and succinylcholine for short procedures (e.g. ambulatory anaesthesia). Rocuronium bromide (rocuronium) is a relatively low-potent, intermediateacting NMBA. Its main advantage is the rapid onset of neuromuscular block whereby good or excellent intubating conditions are achieved within 60 to 90 seconds after rocuronium 0.6 mg/kg (2 x ED95), and within 60 to 180 seconds after smaller doses (1 to 1.5 x ED95). Larger doses of rocuronium (> or = 1 mg/kg) seem to be suitable for rapid-sequence induction under relatively light anaesthesia. However, it is still a matter of controversy whether, in the case of an unanticipated difficult intubation, the long duration of rocuronium administered in such large doses outweighs the many adverse effects of succinylcholine. Rocuronium has mild vagolytic effects and does not release histamine, even when administered in large doses. Rocuronium is primarily eliminated via the liver and its pharmacokinetic profile is similar to that of vecuronium bromide (vecuronium). Unlike vecuronium, rocuronium has no metabolite. Cisatracurium besilate (cisatracurium), the IR-cis, 1'R-cis isomer of atracurium besilate (atracurium) is approximately 4 times more potent than atracurium. The onset time of cisatracurium is significantly slower than after equipotent doses of atracurium. The recommended intubating dose is 0.15 to 0.2 mg/kg (3 to 4 times ED95). Over a wide range of clinically relevant doses the recovery properties of cisatracurium are affected by neither the size of the bolus dose nor by the duration of infusion. Unlike atracurium, cisatracurium does not trigger histamine release. Like atracurium, cisatracurium undergoes Hofmann elimination. In contrast to atracurium, cisatracurium does not undergo hydrolysis by nonspecific plasma esterases. Moreover, about 77% of the drug is cleared by organ-dependent mechanisms.

Less postoperative nausea and vomiting after propofol + remifentanil versus propofol + fentanyl anaesthesia during plastic surgery

BACKGROUND

The effect of different opioids on postoperative nausea and vomiting (PONV) has not been conclusively determined yet, thus the aim of this study was to compare the incidence of PONV in propofol-anaesthetized patients receiving either fentanyl or remifentanil as opioid supplement.

METHODS

Sixty ASA physical status I and II patients scheduled for plastic surgery gave their written informed consent for this prospective, randomized, double-blind study. Anaesthesia was induced with propofol, rocuronium and fentanyl (n = 30; 2 microg kg(-1)) or remifentanil (n = 30; 1 microg kg(-1)). After tracheal intubation, anaesthesia was maintained with propofol, oxygen in air and an infusion of the opioid studied, which was modified according to clinical criteria. Baseline postoperative analgesia was achieved with intravenous propacetamol + metamizol. Intravenous morphine was given if visual analogic scale (VAS) for pain was > or = 4 (scale 0-10) and metoclopramide was administered if a patient presented > or = 2 PONV episodes (nausea or vomiting) in less than 30 min. Postoperatively (2, 12 and 24 h), we registered VAS, rescue morphine consumption, number of patients with episodes of PONV and number of patients requiring metoclopramide. P < 0.05 was considered significant.

RESULTS

There were no significant differences between groups in the demographic parameters, ASA physical status, propofol dose, VAS, and rescue morphine requirements. Fourteen patients in the fentanyl group and four in the remifentanil group presented PONV episodes 2-12 h postoperative hours' interval; (P < 0.05). Ten patients in the fentanyl group and four in the remifentanil group presented vomiting episodes in the same period (P < 0.05); and eight patients in the fentanyl group and one in the remifentanil group required metoclopramide; (P < 0.05). The number of postoperative PONV episodes were low, both in the 0-2-h period (n = 2 vs. n = 1, fentanyl and remifentanil, respectively) and in the 12-24-h period (n = 3 vs. n = 1).

CONCLUSION

Propofol + fentanyl anaesthesia resulted in a higher incidence of PONV and requirements of antiemetic drugs in the period between 2 and 12 postoperative hours compared with propofol + remifentanil, in patients undergoing plastic surgery.

Worsening of anemia by angiotensin converting enzyme inhibitors and its prevention by antiestrogenic steroid in chronic hemodialysis patients

The effects of angiotensin converting enzyme (ACE) inhibitors and their combined use with an antiestrogenic steroid on erythropoiesis were investigated in patients on chronic hemodialysis (CHD). Hematocrit was decreased by 10% or more in 6 of 12 patients who received either captopril or enalapril for 2-6 months. Erythropoietin (Epo) and angiotensin II (AII) were significantly reduced in these patients. When treatment with mepitiostane was combined with ACE inhibitor, anemia was significantly improved but without evidence of changes in circulating Epo concentrations or indices of renin-angiotensin activity. The reduction of AII and Epo formation by ACE inhibitors seems to play an important role in the worsening of anemia in patients on CHD; addition of an antiestrogenic steroid should be considered.

Genes and hypertension

The combination of investigation of rare Mendelian forms of hypertension, candidate gene studies, comparative mapping and genome-wide screening in both animal models and man has led to significant progress in determining new mechanisms of blood pressure control. In this review, the newly discovered blood pressure/cardiovascular genes, WNK kinases and angiotensin converting enzyme 2 and the development of a new anti-hypertensive agent PST2238 are discussed. Major genes causing essential hypertension have yet to be discovered, however, there are now over 20 published genome-wide screens for blood pressure controlling genes. Several regions demonstrate suggestive linkage to the trait and there is some overlap of regions between the different studies. It is hoped that new blood pressure genes will ultimately be discovered using this method. Pharmacogenetic studies in hypertension have only been initiated recently, some are described in this paper. Small studies upon single candidate genes, suggest that the contribution of genetics to the inter-individual variation in blood pressure response to anti-hypertensive therapy, is small, approximately 3-5%. Recently micro-arrays with multiple polymorphisms in multiple genes have been used. After accounting for the additive affects of multiple blood pressure loci, an individual's genetic profile appeared to explain up to 50% of the variation in blood pressure response to therapy. Knowledge of the genetic variants that cause hypertension and influence response to anti-hypertensive therapy will ultimately provide a greater understanding of the molecular mechanisms underlying blood pressure control.

Succinylcholine: adverse effects and alternatives in emergency medicine

Succinylcholine has long been the favored neuromuscular blocking agent for emergent airway management because of its rapid onset, dependable effect, and short duration. However, it has a plethora of undesirable side effects, ranging from the inconsequential to the catastrophic. When patients requiring tracheal intubation present with potential contraindications to succinylcholine use, the emergency physician will need to substitute a rapid-onset nondepolarizing neuromuscular blocking agent, such as rocuronium or mivacurium. An understanding of the pharmacology of these agents is essential.

Comparison of succinylcholine and rocuronium for first-attempt intubation success in the emergency department

OBJECTIVES

The objective was to determine the effect of paralytic type and dose on first-attempt rapid sequence intubation (RSI) success in the emergency department (ED).

METHODS

This was a retrospective evaluation of information collected prospectively in a quality improvement database between July 1, 2007, and October 31, 2008. Information regarding all intubations performed in a tertiary care ED was recorded in this database. All RSI performed using succinylcholine or rocuronium were included. Logistic regression was used to analyze the effect of paralytic type and dosing, as well as age, sex, body mass index, physician experience, device type, and presence of difficult airway predictors on first attempt RSI success.

RESULTS

A total of 327 RSI were included in the final analyses. All patients received etomidate as the induction sedative and were successfully intubated. Of these, 113 and 214 intubations were performed using succinylcholine and rocuronium, respectively. The rate of first-attempt intubation success was similar between the succinylcholine and rocuronium groups (72.6% vs. 72.9%, p=0.95). Median doses used for succinylcholine and rocuronium were 1.65 mg/kg (interquartile range [IQR]=1.26-1.95 mg/kg) and 1.19 mg/kg (IQR=1-1.45 mg/kg), respectively. In the univariate logistic regression analyses, variables predictive of first-attempt intubation success were laryngeal view (more success if Grade 1 or 2 compared to Grade 3 or 4 of the Cormack-Lehane classification, odds ratio [OR] =55.18, 95% confidence interval [CI]=18.87 to 161.39), intubation device (less success if direct laryngoscopy, OR=0.57, 95% CI=0.34 to 0.96), and presence of a difficult airway predictor (OR=0.55, 95% CI=0.31 to 0.99). In the multivariate analysis, the only variable predictive of first-attempt intubation success was laryngeal view.

CONCLUSIONS

Succinylcholine and rocuronium are equivalent with regard to first-attempt intubation success in the ED when dosed according to the ranges used in this study.

Bilateral sixth cranial nerve palsy after unintentional dural puncture

PURPOSE

Bilateral sixth nerve palsy is a known though uncommon complication following dural puncture. The recommended treatment consists of hydration and alternate monocular occlusion. The value and the timing of an epidural blood patch (EBP) for sixth nerve palsy remains controversial as some authors have demonstrated benefits in performing an EBP early in course of the nerve palsy whereas others have not found any advantage when an EBP was performed later.

CLINICAL FEATURES

A 40-yr-old woman developed bilateral sixth nerve palsy ten days after an unintentional dural puncture. An EBP was done within 24 hr after the onset of the symptoms and immediate improvement of the diplopia was noted by the patient and confirmed by an ophthalmologist. Complete resolution of the diplopia occurred 36 days after the dural puncture.

CONCLUSION

Blood patching within 24 hr of the onset of diplopia may be a reasonable treatment for ocular nerve palsy as it relieved the postdural puncture headache and produced partial improvement of the diplopia.

Hypertension, Na+/Ca2+ exchanger, and Na+, K+-ATPase

Hypertension is the most prevalent risk factor for stroke, myocardial infarction, or end-stage renal failure. The critical importance of excess salt intake in the pathogenesis of hypertension is widely recognized, but the mechanisms whereby salt intake elevates blood pressure have puzzled researchers. Recent studies using Na+/Ca2+ exchange inhibitors and genetically engineered mice provide evidence that vascular Na+/Ca2+ exchanger type 1 (NCX1) is involved in the development of salt-dependent hypertension. Endogenous cardiac glycosides, which may contribute to salt-dependent hypertension, seem to be necessary for NCX1-mediated hypertension. Intriguingly, studies using knock-in mice with modified cardiac glycoside binding affinity of Na+,K+-ATPases provide a clear demonstration that this cardiac glycoside-binding site plays an important role in blood pressure regulation. Taken all together: (1) endogenous cardiac glycosides are secreted after high salt intake; (2) these cardiac glycosides inhibit Na+,K+-ATPase in vascular smooth muscle cells; (3) this inhibition results in the elevation of local Na+ on the submembrane area; and (4) this elevation of local Na+ facilitates Ca2+ entry through NCX1, resulting in vasoconstriction. This proposed pathway may have enabled us to explain how to link dietary salt to hypertension.

Anesthesia during high-field intraoperative magnetic resonance imaging experience with 80 consecutive cases

Intraoperative magnetic resonance imaging (MRI) has been used for years to update neuronavigation and for intraoperative resection control. For this purpose, low-field (0.1-0.2 T) MR scanners have been installed in the operating room, which, in contrast to machines using higher magnetic field strength, allowed the use of standard anesthetic and surgical equipment. However, these low-field MR systems provided only minor image quality and a limited battery of MR sequences, excluding functional MRI, diffusion-weighted MRI, or MR angiography and spectroscopy. Based on these advantages, a concept using high-field MRI (1.5 T) with intraoperative functional neuronavigational guidance has been developed that required adaptation of the anesthetic regimen to working in the close vicinity to the strong magnetic field. In this paper the authors present their experience with the first 80 consecutive patients who received anesthesia in a specially designed radio frequency-shielded operating room equipped with a high-field (1.5 T) MR scanner. We describe the MR-compatible anesthesia equipment used including ventilator, monitoring, and syringe pumps, which allow standard neuroanesthesia in this new and challenging environment. This equipment provides the use of total intravenous anesthesia with propofol and remifentanil allowing rapid extubation and neurologic examination following surgery. In addition, extended intraoperative monitoring including EEG monitoring required for intracranial surgery is possible. Moreover, problems and dangers related to the effects of the strong magnetic field are discussed.

Steroid hormone receptors and clinical usefulness in human breast cancer

For more precise prediction of response to endocrine therapy in patients with advanced breast cancer, we investigated the correlation between the presence of combination of estrogen (ER), progesterone (PgR) receptors, or combination of ER, PgR and androgen receptor (AR) and response to therapy. The patients with ER+, PgR+ tumors survived longer than those with ER+, PgR-, or ER-, PgR- tumors. A better response rate with longer survival time was obtained in patients with tumors that had three positive receptors or PgR+ and/or AR+ in addition to ER+ than in those with tumors of other combinations. According to the sequential assays of ER in tumors in several stages of breast cancer, it is likely that the positive rate of ER becomes lessened by the progression of cancer and by treatments. We stressed the significance of steroid hormone receptor assay in the mastectomy specimens for the prediction of response of therapy in case of the future recurrence of malignancy.

Newer neuromuscular blocking drugs. An overview of their clinical pharmacology and therapeutic use

Four new nondepolarising muscle relaxants, pipecuronium bromide, doxacurium chloride, mivacurium chloride and Org 9426 (rocuronium) offer alternatives to the established agents atracurium besilate and vecuronium bromide. Pipecuronium and Org 9426 are steroidal compounds, the latter being a monoquaternary agent, whereas doxacurium and mivacurium are bisquaternary benzylisoquinolinium compounds. Pipecuronium and doxacurium have a relatively slow onset and a long duration of action. Pipecuronium produces maximum block in 3 to 6 min when given in a dose of 45 to 80 micrograms/kg, and a duration of clinical relaxation of between 40 and 110 min. Doxacurium is more potent, but is the least rapid and the longest acting relaxant currently available. When administered in doses of 37 to 80 micrograms/kg, it produces maximum block within 3.5 to 10 min, with a duration of clinical relaxation of 77 to 164 min. The advantage of both pipecuronium and doxacurium is their cardiovascular stability. Both agents are primarily eliminated via the kidneys and both have now been licensed for use in the US. Mivacurium is a muscle relaxant with a short duration of action. When administered in doses of 0.1 to 0.25 mg/kg it produces maximum block in 2 to 4 min, but the duration of clinical relaxation is less than 20 min. Higher doses which could induce a faster neuromuscular block are unfortunately associated with some histamine liberation. The drug is metabolised by plasma cholinesterase. Mivacurium has also been licensed for use in the US. Org 9426 is an agent with a rapid onset but an intermediate duration of action. A dose of 0.5 to 0.6 mg/kg induces maximum block in about 1.5 min and has a duration of clinical relaxation of about 30 min. The rapid onset of effect could be useful for early intubation as an alternative to suxamethonium chloride. However, much more clinical experience is needed with this agent, particularly with regard to duration of action of larger doses and occurrence of side effects. The drug is mainly eliminated via the liver.

Induction with sevoflurane-remifentanil is comparable to propofol-fentanyl-rocuronium in PONV after laparoscopic surgery

PURPOSE

To compare sevoflurane-remifentanil induction and propofol-fentanyl-rocuronium induction with regards to the frequency of moderate to severe postoperative nausea and vomiting (PONV) in the first 24 hr after laparoscopic day surgery.

METHODS

After informed consent, 156 ASA physical status class I to III patients undergoing laparoscopic cholecystectomy or tubal ligation were randomized to either induction with sevoflurane 8%, N(2)O 67% and iv remifentanil 1 to 1.5 microg.kg(-1) or induction with iv fentanyl 2 to 3 microg.kg(-1), propofol 2 mg.kg(-1), and rocuronium 0.3 to 0.5 mg.kg(-1). All patients received iv ketorolac 0.5 mg.kg(-1) at induction and sevoflurane-N(2)O maintenance anesthesia with rocuronium as needed. PONV was treated with iv ondansetron, droperidol, or dimenhydrinate; postoperative pain was treated with opioid analgesics. Patients were followed for 24 hr with regards to PONV and pain. Intubating conditions, induction and emergence times, time to achieve fast-track discharge criteria, and drug costs were measured.

RESULTS

No differences were seen between the two groups in their frequencies of 24-hr moderate to severe PONV and postoperative pain, or in their intubating conditions, induction and emergence times, and time to achieve fast-track discharge criteria. Patients undergoing sevoflurane-remifentanil induction received more morphine (11 mg vs 8 mg; P < 0.001) in the postanesthetic care unit. Sevoflurane-remifentanil induction resulted in similar anesthetic and total drug costs for both procedures.

CONCLUSION

We did not demonstrate any difference in PONV, pain, or anesthetic/recovery times or costs between the sevoflurane and propofol groups. Sevoflurane-remifentanil induction is a feasible technique for anesthetic induction.

A comparison of succinylcholine and rocuronium for rapid-sequence intubation of emergency department patients

OBJECTIVE

To compare rocuronium and succinylcholine for rapid-sequence intubation (RSI) in the emergency department (ED).

METHODS

A one-year prospective cohort comparison study was performed using a data collection form completed at the time of intubation. Data collected included the reason for the neuromuscular-blocking agent (NMBA) chosen, the time to onset of paralysis, and any complications encountered. Three ten-point numerical descriptor scales recorded the degree of body movement, vocal cord movement, and the physician's overall satisfaction with the extent of paralysis.

RESULTS

Succinylcholine was used in 382 patients and rocuronium was used in 138 (26% of all RSI) patients. The mean (+/- SD) times of onset of succinylcholine and rocuronium were 39 +/- 13 sec and 44 +/- 20 sec, respectively (p = 0.04). No patient desaturated and required assisted ventilations while waiting for paralysis to occur. Types of body movements were similar with the two agents, but less frequent with succinylcholine (median = 10, mean = 9.5 +/- 1.1) than rocuronium (median = 10, mean = 9.1 +/- 1. 5) (p = 0.01). Vocal cord movements were similar for succinylcholine (median = 10, mean = 9.2 +/- 1.6) and rocuronium (median = 9, mean = 9.0 +/- 1.6) (p = 0.15). The physician's overall satisfaction with the extent of paralysis was also higher for succinylcholine (median = 10, mean = 9.4 +/- 1.3) than rocuronium (median = 10, mean = 8.8 +/- 2.0) (p < 0.01). Only one complication, widening of the QRS complex secondary to succinylcholine use in a patient with unsuspected hyperkalemia, could be attributed to the choice of NMBA.

CONCLUSIONS

Both succinylcholine and rocuronium produced fast and reliable paralysis for RSI. Although succinylcholine had a faster onset and provided more relaxation, the difference had no clinical significance. Approximately a fourth of ED RSI patients qualified for use of rocuronium using these high-risk criteria.

Rocuronium pretreatment reduces suxamethonium-induced myalgia: comparison with vecuronium

We have studied, in 150 patients undergoing elective oral surgery, the effectiveness and sequelae of pretreatment with rocuronium for reducing myalgia after suxamethonium. Patients were allocated randomly to one of three groups: anaesthesia was induced with propofol and fentanyl, and group V received vecuronium 1 mg, group R rocuronium 6 mg and group P placebo pretreatment. Suxamethonium 1.5 mg kg-1 was given 60 s after the pretreatment agent. All patients received ketorolac 10 mg i.v. and morphine 10 mg i.m. for analgesia. The incidence of postoperative myalgia on day 1 after rocuronium (20%) was significantly less than after vecuronium (42%) (P < 0.05) or placebo (70%) (P < 0.01). By day 4 the incidence of myalgia was 28.6% in the rocuronium group, 46.3% in the vecuronium group and 95% in the placebo group. Intubating conditions were not affected adversely by any pretreatment regimen.

Neuromuscular blocking agents in the emergency department

Neuromuscular blocking agents (NMBAs) are utilized frequently in the emergency department (ED). We begin with a brief history of neuromuscular blockade, then review the indications and guidelines for its use in the emergency department setting. The relevant agents will be discussed focusing on dosage, side effects, and adverse reactions. Special attention will be paid to succinylcholine, the drug most commonly employed in the ED setting, followed by a summary of the nondepolarizing agents currently available, in particular the four shorter-acting agents that are most appropriate for administration in the ED.

Ouabain antagonists as antihypertensive agents

The evidence that high levels of endogenous ouabain (EO), a closely related isomer of ouabain, are implicated in human hypertension and cardiac hypertrophy and failure stimulated the pharmacological research for developing novel anti-hypertensive agents active as ouabain antagonists. The pathogenetic mechanisms through which increased EO levels affect cardiovascular system involve the modulation of Na-K ATPase, the key enzyme responsible for renal tubular sodium reabsorption and the activation of signalling transduction pathways implicated in growth-related gene transcription. By studying both genetic and experimental rat models of hypertension and comparing them with humans, our group has demonstrated that elevated levels of circulating EO and the genetic polymorphism of the cytoskeletal protein adducin associate with hypertension and high renal Na-K pump activity. Ouabain itself induces hypertension and up-regulates renal Na-K pump when chronically infused at low doses into rats (OS). In renal cultured cells, either incubated for several days with nanomolar concentrations of ouabain or transfected with the hypertensive adducin genetic variant, the Na-K pump results enhanced. Moreover, both EO and adducin polymorphism affect cardiac complications associated to hypertension, the former through the activation of a signalling transduction pathway. As a consequence, a compound able to interact with the cellular and molecular alterations, sustained by EO or mutated adducin, may represent the suitable treatment for those patients in whom these mechanisms are at work. A new antihypertensive compound, PST 2238, that selectively antagonises the pressor effect and the alteration of renal Na-K pump, sustained both by ouabain and adducin polymorphism, is described. A selective ability of PST 2238 to antagonise the ouabain-induced organ hypertrophy is also documented. The specificity of PST 2238 mechanism of action is supported by the absence of interactions with receptors or hormones involved in blood pressure regulation and by the lack of diuretic activity and diuretic-associated side effects. It is concluded that this compound could be useful for the treatment of those forms of essential hypertension in which renal Na handling alterations and cardiac complications are associated with either increased EO levels and/or adducin polymorphism.

Succinylcholine or rocuronium? A meta-analysis of the effects on intubation conditions

This meta-analysis was undertaken to compare the effects of succinylcholine (SCH) and rocuronium (RCR) on endotracheal intubation (ETI) conditions. Eligible randomised controlled trials (RCTs) were identified via medline and a manual search of references. The frequencies of excellent and unacceptable ETI conditions in subjects receiving SCH 1.0-1.5 mg/kg and RCR 0.6-1.2 mg/kg were determined using standard statistical methods. Inclusion criteria were met by 16 RCTs, representing 1362 subjects. SCH was associated with a 17.7% increase (95% CI = 13-22) in the frequency of excellent ETI conditions and a 5.1% decrease (95% CI = -7.3 to -2.9) in the frequency of unacceptable ETI conditions, when compared with RCR. In the subgroup undergoing true rapid sequence intubation, SCH was associated with a 19.1% increase (95% CI = 13.7-24.5) in the frequency of excellent ETI conditions. SCH appears to be superior to RCR in creating excellent ETI conditions and avoiding unacceptable ETI conditions.

Regression of a presumed meningioma with the antiestrogen agent mepitiostane. Case report

This 68-year-old woman underwent a distal gastrectomy for gastric cancer in August 1994. A presumed meningioma of the falx was found incidentally on a staging examination of the gastric cancer, but the meningioma was not treated with surgery. Instead, after gastrectomy the patient received tegafur as adjuvant chemotherapy until February 1996, when she was readmitted to the hospital because of loss of appetite and emaciation but with no recurrence of the gastric cancer. A computerized tomography scan obtained during this second admission showed no change in the meningioma. To improve her general condition, tegafur was discontinued and she was started on a course of the antiestrogen agent mepitiostane. Administration of mepitiostane for approximately 2 years resulted in a marked regression (73%) of the meningioma. This is the first reported case of a presumed meningioma that regressed as a result of use of the antiestrogen agent mepitiostane.

OASIS-HT: design of a pharmacogenomic dose-finding study

Experimental evidence and observations in humans strongly support an interactive role of mutated α-adducin, sodium (Na+)/potassium (K+)-adenosine triphosphatase (ATPase) activity and endogenous ouabain in Na+ homeostasis and the pathogenesis of hypertension. The Ouabain and Adducin for Specific Intervention on Sodium in HyperTension (OASIS-HT) trial is an early Phase II dose-finding study, which will be conducted across 39 European centers. Following a run-in period of 4 weeks without treatment, eligible patients will be randomized to one of five oral doses of rostafuroxin consisting of 0.05, 0.15, 0.5, 1.5, or 5.0 mg/day. Each dose will be compared to a placebo in a double-blind crossover experiment with balanced randomization. Treatment will be initiated with the active drug and continued with placebo or vice versa. Each double-blind period will last 5 weeks. The primary end point is the reduction in systolic blood pressure defined as the average of three clinic readings with the patient in the sitting position. Secondary end points include the reduction in diastolic blood pressure on clinic measurement, the decrease in the 24-h blood pressure, and the incidence of end points related to safety. Secondary objectives are to investigate the dependence of the blood pressure-lowering activity on the plasma concentration of endogenous ouabain and the genetic variation of the enzymes involved in the metabolism of this hormone, and the adducin cytoskeleton proteins. Eligible patients will have Grade I or II systolic hypertension without associated conditions and no more than two additional risk factors. In conclusion, OASIS-HT is a combination of five concurrent crossover studies, one for each dose of rostafuroxin to be studied. To our knowledge, OASIS-HT is the first Phase II dose-finding study in which a genetic hypothesis is driving primary and secondary end points.