Muscle Weakness after Muscle Relaxants: An Audit of Clinical Practice

Residual muscle weakness after general anaesthesia, assessed using handgrip strength, was audited in a teaching hospital. The relationships between residual weakness, the use of muscle relaxants and patient characteristics were examined.

Handgrip strength was measured preoperatively, one hour postoperatively and one day postoperatively using a hand dynamometer in 151 patients having general anaesthesia. Forty-nine patients received no muscle relaxant, 34 patients received vecuronium and 68 received rocuronium. Patients were managed by their anaesthetist according to that anaesthetist's clinical choice. All patients who received muscle relaxants received neostigmine.

One hour postoperatively, there was a decline in handgrip strength of 16% for the no relaxant group, 24% for vecuronium and 29% for rocuronium. The degree of weakness for the relaxant groups was unrelated to age (P=0.89) but was strongly influenced by the patient's sex. Almost all of the increased weakness with relaxants was found in the female patients. The mean decline in handgrip strength in the male patients who received either vecuronium or rocuronium was similar to that seen when relaxants had not been used (P=0.40). One hour postoperatively, female patients showed a marked decrease in handgrip strength after both vecuronium and rocuronium (32% and 34% respectively, combined P=0.01).

These results suggest that in usual clinical practice at our institution, female patients are more likely to have residual weakness after muscle relaxants.

A Randomized Trial of Respiratory Status during Airway Stenting under General Anesthesia Spontaneous Respiration vs. Controlled Ventilation with Muscle Relaxants

Airway stenting is a procedure in which a stent is inserted into a stenotic site in the airway. However, the optimal ventilation for airway stenting remains controversial. We have planned a randomized, unblinded controlled study to compare intraoperative respiratory status by dividing patients, who underwent airway stenting, into spontaneous respiration (SP) and controlled ventilation with muscle relaxants (MR) groups. This study started in April 2016. The subjects, patients aged ≥20 years with airway stenosis caused by malignant neoplasms for which airway stenting was scheduled, are randomly allocated to SP and MR groups. Anesthesia management is performed in accordance with the anesthetic methods established in each group to compare parameters of the intraoperative respiratory status. The primary endpoint is the incidence of intraoperative oxygen desaturation events (SpO₂ <95). Secondary endpoints are the mean intraoperative P/F ratio, pH, PaCO₂, adverse events, and proportion of protocol treatment achievement. Currently, there is no evidence of anesthetic methods affecting airway stenting. Some studies have claimed that muscle relaxants worsen airway stenosis, while others have reported stable anesthetic management of controlled ventilation with muscle relaxants in airway stenting. This study may aid in clarifying anesthetic methods for airway stenting.

Muscle Relaxants as a Risk Factor for Vis-à-tergo During Penetrating Keratoplasty: A Prospective Interventional Study

INTRODUCTION

This study aimed to investigate the influence of three muscle relaxants on intraocular pressure (IOP), ocular pulse amplitude (OPA), and vis-à-tergo (VAT) in patients undergoing penetrating keratoplasty (PKP) under general anesthesia.

METHODS

Ninety-five patients undergoing PKP were included in this prospective single-center interventional study. IOP and OPA were measured with a dynamic contour tonometer before and 5 min after onset of general anesthesia. Mivacurium (n = 30), atracurium (n = 35), and rocuronium (n = 30) were administered as nondepolarizing muscle relaxants. VAT was assessed 15 min after surgery had begun.

RESULTS

When mivacurium was used, IOP decreased by 2.2 mmHg [standard deviation (SD) ±2.2 mmHg; p < 0.001]. Atracurium decreased the IOP by an average of 5.8 mmHg (SD ±1.8 mmHg; p < 0.001) and rocuronium caused an IOP reduction of 7.2 mmHg (SD ±2 mmHg; p < 0.001). The relative IOP decrease was 12% with mivacurium, 29% with atracurium, and 37% with rocuronium (p < 0.001). OPA decreased by 0.6 mmHg with mivacurium (SD ±0.6 mmHg; 26%; p < 0.001), 1.3 mmHg with atracurium (SD ±1.3 mmHg; 40%; p < 0.001), and 1.2 mmHg with rocuronium (SD ±0.7 mmHg; 42%; p < 0.001). The relative OPA decrease was 26% with mivacurium, 40% with atracurium, and 42% with rocuronium (p < 0.001). VAT occurred in 36% of cases. Mivacurium was used in 77% of these cases, atracurium in 26%, and rocuronium in 6.6% (p < 0.001).

CONCLUSIONS

Mivacurium is associated with a higher risk of VAT during PKP. Therefore, atracurium or rocuronium may minimize complications in ocular surgery with large incisions.

Use of neuromuscular blockers and neostigmine for general anesthesia and its association with neuraxial blockade: A retrospective study

This research aimed to assess the use of neuromuscular blockers (NMB) and its reversal, associated or not with neuraxial blockade, after general anesthesia.This retrospective study analyzed 1295 patients that underwent surgery with general anesthesia at Prof. Dr. José Aristodemo Pinotti Hospital in 2013. The study included patients aged >1 year, with complete, readable medical charts and anesthetic records.Rocuronium (ROC) was the most used NMB (96.7%), with an initial dose of 0.60 (0.52-0.74) mg/kg and total dose of 0.38 (0.27-0.53) mg/kg/h. In 24.3% of the cases, neuraxial blockade was associated with a significantly longer anesthesia (P < .001) than in cases without neuraxial block, regardless of technique (total intravenous (TIV) vs intravenous and inhalational (IV+IN)). In 71.9% of the cases, a single dose of NMB was used. Patients under TIV general anesthesia associated with neuraxial blockade had a lower total dose of ROC (mg/kg/h) in comparison with TIV GA alone (0.30 (0.23-0.39) and 0.42 (0.30-0.56) mg/kg/h, respectively, P < .001). The same was observed for patients under IV+IN GA (0.32 (0.23-0.41) and 0.43 (0.31-0.56) mg/kg/h, respectively, P < .001). The duration of anesthesia was longer according to increasing number of additional NMB doses (P < .001). Dose of neostigmine was 2.00 (2.00-2.00) mg or 29.41 (25.31-33.89) μg/kg. The interval between neostigmine and extubation was >30 minutes in 10.9% of cases.The most widely used NMB was ROC. Neuroaxial blockade (spinal or epidural) was significantly associated with reduced total dose of ROC (mg/kg/h) during general anesthesia, even in the absence of neuromuscular monitoring and regardless of general anesthetic technique chosen. In most cases, neostigmine was used to reverse neuromuscular block. The prolonged interval between neostigmine and extubation (>30 minutes) was neither associated with total doses of ROC or neostigmine, nor with the time of NMB administration. This study corroborates the important role of quantitative neuromuscular monitors and demonstrates that neuraxial blockade is associated with reduced total ROC dose. Further studies are needed to evaluate the possible role of neuraxial blockade in reducing the incidence of postoperative residual curarization.

Use of sugammadex in a patient with progressive muscular atrophy and in a patient with amyotrophic lateral sclerosis: Case report

INTRODUCTION

We herein present 2 cases involving the combination of rocuronium and sugammadex in patients with motor neuron disease. The patients were a 54-year-old man with progressive muscular atrophy who underwent removal of internal fixators in the arm and leg, and a 66-year-old woman with amyotrophic lateral sclerosis who underwent skin grafting in the left lower leg. General anesthesia was induced with propofol, rocuronium, and remifentanil and maintained with desflurane and remifentanil. At the end of the surgical procedure, we administered sugammadex. Three or 4 minutes after administration of sugammadex, the patients began to breathe spontaneously and were extubated without complications.

CONCLUSION

Sugammadex can be used successfully to reverse neuromuscular blockade in patients with motor neuron disease.

Is neuromuscular blocker needed in children undergoing inguinal herniorrhaphy?: A prospective, randomized, and controlled trial

BACKGROUND

Intraoperative neuromuscular blocker is widely used, but is known to be associated with postoperative residual paralysis, which is known to be associated with increased risk of pulmonary complications. Hence, its use should be individualized and restricted to procedures where it is mandatory. We examined whether not using a neuromuscular blocker affects the surgical conditions in children undergoing inguinal herniorrhaphy.

METHODS

Anesthesia was induced and maintained with sevoflurane in 60% nitrous oxide, and the airway was maintained using an I-gel. In total, 66 children aged 1 to 6 years were randomized to receive rocuronium (rocuronium group, n = 33) or saline (control group, n = 33); 61 children of them finished the study. A single surgeon who performed the operation rated the surgical condition of each patient on a 4-point scale (1 = poor, 2 = acceptable, 3 = good, and 4 = excellent). Intraoperative patient movement, recovery time, emergence agitation, and postoperative pain scores were evaluated.

RESULTS

One patient in control group and no patient in rocuronium group showed intraoperative movement. When noninferiority test was done for intraoperative patient movement, with the noninferiority margin of 20%, the difference of absolute risk was 3.3% (95% confidence interval -8.0% to 16.7%) and saline group was noninferior to rocuronium group. All of the patients showed good to excellent surgical conditions, and no difference was found between the 2 groups. The recovery time was shorter in the control group than in the rocuronium group (4.5 ± 1.8 vs 5.6 ± 2.2 minutes, respectively; P = .028).

CONCLUSION

In children aged 1 to 6 years undergoing inguinal herniorhaphy under sevoflurane anesthesia using an I-gel, not using neuromuscular blocker showed similar intraoperative condition and shortened recovery time compared with using neuromouscular blocker.

The administration sequence of propofol and remifentanil does not affect the ED50 and ED95 of rocuronium in rapid sequence induction of anesthesia: a double-blind randomized controlled trial

OBJECTIVE

The topic of drug administration sequence in rapid sequence induction (RSI) is still an object of interest in terms of rocuronium effectiveness. The aim of this prospective, randomized trial was to evaluate the effect of administration sequence of propofol and remifentanil on ED50 and ED95 of rocuronium in a RSI model.

PATIENTS AND METHODS

Eighty-four patients were randomized into Group Remifentanil (Group R, n = 43), where induction of general anesthesia started with remifentanil (2 µg/kg) and followed by propofol (2 mg/kg) and rocuronium administrations; and Group Propofol (Group P, n = 41), where induction of general anesthesia started with propofol and followed by remifentanil and rocuronium. First patients in each group were paralyzed by 0.8 mg/kg rocuronium. In case of acceptable intubation as evaluated according to the criteria described by Viby-Mogensen et al, rocuronium dose was decreased by 0.1 mg/kg for the next patient; otherwise, rocuronium dose was increased by 0.1 mg/kg. After three crossover points, increments or decrements in rocuronium dosage were set to 0.05 mg/kg. The process was repeated until a total of ten crossover points were obtained.

RESULTS

The ED50 and ED95 doses of rocuronium were similar in Group R (0.182 mg/kg, and 0.244 mg/kg, respectively) and Group P (0.121 mg/kg, and 0.243 mg/kg, respectively) according to 95% CI of the estimates. There was no statistically significant difference in terms of clinically acceptable intubation conditions between the two groups (56.1% in Group R vs. 59% in Group P, p = 0.795).

CONCLUSIONS

The choice of administration sequence of propofol and remifentanil does not have an impact on estimated ED50 and ED95 of rocuronium in providing acceptable intubation conditions in the RSI technique.

[EFFICACY AND SAFETY OF ROCURONIUM BROMIDE PRODUCED IN THE RUSSIAN FEDERATION: A SINGLE-BLIND RANDOMIZED CLINICAL TRIAL]

DESIGN

A single-blind comparative prospective randomised clinical trial.

OBJECTIVE

To evaluate the efficacy and safety of Russian muscular relaxant (Kruarone) in comparison with Esmerone in multicomponent balanced anesthesia during laparoscopic cholecystectomy. 80 patients (23-68 years old) were examined. The patients were randomized into two equal groups. The results showed that Kruarone was effective relaxant with rapid onset of action, providing optimal conditions for muscle relaxation for laryngoscopy and tracheal intubation. Kruarone did not require frequent administration supports, providing high quality and stable neuromuscular blockade during surgery. There was no any one case of adverse events for the entire period of 24-hour surveillance, the drug has no cumulative effect. Kruarone did not cause allergic reactions and had no significant effect on hemodynamics. Thus Kruarone 0.6 mg/kg with an average total flow rate of the drug within 55 mg (39.6-75.43 mg) has the same effectiveness and safety with Esmerone in similar dosages.

Resting energy expenditure and substrate oxidation rates correlate to temperature and outcome after cardiac arrest - a prospective observational cohort study

INTRODUCTION

Targeted temperature management improves outcome after cardiopulmonary resuscitation. Reduction of resting energy expenditure might be one mode of action. The aim of this study was to correlate resting energy expenditure and substrate oxidation rates with targeted temperature management at 33°C and outcome in patients after cardiac arrest.

METHODS

This prospective, observational cohort study was performed at the department of emergency medicine and a medical intensive care unit of a university hospital. Patients after successful cardiopulmonary resuscitation undergoing targeted temperature management at 33°C for 24 hours with subsequent rewarming to 36°C and standardized sedation, analgesic and paralytic medication were included. Indirect calorimetry was performed five times within 48 h after cardiac arrest. Measurements were correlated to outcome with repeated measures ANOVA, linear and logistic regression analysis.

RESULTS

In 25 patients resting energy expenditure decreased 20 (18 to 27) % at 33°C compared to 36°C without differences between outcome groups (favourable vs. unfavourable: 25 (21 to 26) vs. 21 (16 to 26); P = 0.5). In contrast to protein oxidation rate (favourable vs. unfavourable: 35 (11 to 68) g/day vs. 39 (7 to 75) g/day, P = 0.8) patients with favourable outcome had a significantly higher fat oxidation rate (139 (104 to 171) g/day vs. 117 (70 to 139) g/day, P <0.05) and a significantly lower glucose oxidation rate (30 (-34 to 88) g/day vs. 77 (19 to 138) g/day; P < 0.05) as compared to patients with unfavourable neurological outcome.

CONCLUSIONS

Targeted temperature management at 33°C after cardiac arrest reduces resting energy expenditure by 20% compared to 36°C. Glucose and fat oxidation rates differ significantly between patients with favourable and unfavourable neurological outcome.

TRIAL REGISTRATION

Clinicaltrials.gov NCT00500825. Registered 11 July 2007.

[AIRWAY MANAGEMENT IN CHILDREN DURING RESECTION OF THE TONSILS]

MATERIALS AND METHODS

We conducted a comparative evaluation of anesthesia used during tracheal intubation with and without the application of muscle relaxants in cases of adenotonsillectomy in children. Intubation parameters were evaluated according to Cormack-Lehane scale; the presence of cough reflex, limb movement, laryngospasm and desaturation during intubation was also taken into account. The presence of cough, husky voice, and complaints of pain in the throat were recorded in the monitoring report after extubation. We used the MOPS scale to evaluate postoperative pain and discomfort in children.

RESULTS

Tracheal intubation in children with adenotonsillectomy without the use of muscle relaxants was successfid in 100% of the cases, despite the fact that, according to the Cormack-Lehane classification, first degree of visualisation of the glottis during direct laryngoscopy was observed in 79.3% of the cases and the second degree was observed in 20.7% of the cases. No significant reactions in the cardiovascular system to the endotracheal tube were noted. The group without the use of muscle relaxants (p < 0.05) experienced earlier extubation and a shorter duration of anesthesia, which in turn contributed to a more rapid activation of the patients. According to the number of post-intubation complications, no significant differences in the two groups were observed. According to the MOPS scale, higher scores (p < 0.05), indicating discomfort in the early postoperative (within the first 15 minutes after the operation) period were observed in the group with the use of muscle relaxants.

CONCLUSIONS

Thus, the method of tracheal intubation without the use of muscle relaxants can be used for adenotonsillectomy in children.

[Effect of an oral anti-estrogen agent (mepitiostane) on the regression of intracranial meningiomas in the elderly]

We report here the regression of meningioma following treatment with the anti-estrogen agent mepitiostane in a series of cases. The first case was that of a 72-year-old woman who presented with coma status due to non-communicating hydrocephalus. A large presumed meningioma within the cerebello-pontine angle was detected on gadolinium-enhanced magnetic resonance imaging (MRI). The patient recovered from the neurological deficit following endoscopic third ventriculostomy treatment, and was administered mepitiostane (10mg/day) orally. Gadolinium-enhanced MRI showed a marked regression (85%) of the meningioma following 60 months of oral medication. The second case was that of a 79-year-old woman with no neurological deficit; however, a presumed meningioma located in the frontal skull base was detected on gadolinium-enhanced MRI. Mepitiostane (10mg/day) was administered orally. Again, a marked regression (88%) of the meningioma was demonstrated after 115 months of oral medication. The third case was that of a 71-year-old woman who presented with right visual disturbance and a visual field defect. Gadolinium-enhanced MRI demonstrated a presumed meningioma located in the left sphenoidal bone. Mepitiostane (20mg/day) was administered orally. An 79% regression of the meningioma was observed after 21 months of oral medication. In these three cases, the marked reduction in meningioma following anti-estrogen agent (mepitiostane) administration suggested that this oral medication could be an effective therapeutic option in elderly patients.

Impairment of recovery of muscle function by residual rocuronium after re-transfusion of intraoperative salvaged blood

BACKGROUND

Recurarization has previously been described in the context of acute normovolemic hemodilution. The aim of this study was to investigate the impairment of recovery of neuromuscular function after re-transfusion of intraoperative salvaged blood in patients treated with rocuronium.

METHODS

We enrolled 50 patients undergoing general anesthesia for lumbar surgery. Intraoperative blood salvage (IBS) was used in 30 patients (group I); the remaining 20 comprised a control group (group C). Anesthesia was induced with fentanyl, midazolam, propofol and rocuronium. Rocuronium was infused to maintain neuromuscular blockade during surgery. Blood was collected from the operative field and re-transfused in the post-anesthesia care unit (PACU). Neuromuscular function was monitored using the train-of-four ratio (TOFr). Once the train-of-four ratio exceeded 90 in the PACU, neuromuscular function was evaluated every 5 minutes for 30 minutes. The TOFr and incremental recovery of TOFr from baseline were recorded. Salvaged blood was re-transfused at the beginning of the evaluation for patients in group I, and afterwards for patients in group C. Blood gas analysis was assessed before anesthesia and in the PACU.

RESULTS

Incremental recovery of TOFr from baseline was significantly less in group I than controls at 25 minutes (6.1 ± 3.2 vs. 9.1 ± 3.2, respectively; P = 0.001) and 30 minutes (7.1 ± 3.2 vs. 10.0 ± 2.2, respectively; P = 0.001). There were no significant differences in gas exchange between the groups.

CONCLUSIONS

In patients who had received a rocuronium infusion during anesthesia, re-transfusion of salvaged blood significantly impaired recovery of neuromuscular function recovery in the PACU, but without significant impairment of respiratory function.

[Assessment of sugammadex use efficiency and safety for neuromuscular block reversion]

Blockade of neuromuscular conductivity is a considered one of basic part of a patient protection in a concept of a balanced multicomponent anesthesia. The controlled neuromuscular paralysis in a combination of a sedation, an analgesia and a hyporeflection not only provides comfortable conditions to surgeons for carrying out surgeries, but also allows to manage a gas exchange, blood circulation and a metabolism in a patient. However in clinical practice there is such complication after application of muscular relaxant (not depolarizing) as a residual curarization. The residual curarization is interfaced to deterioration of the respiratory answer to a hypoxemia, swallowing dysfunction that significantly increased risk of aspiration and risk of postoperative pulmonary complications. Until recent time acetylcholinesterase inhibitors or prolonged ALV before spontaneous regression of the neuromuscular block were applied in clinical practice for the purpose of restoration of adequate neuromuscular conductivity and elimination of a residual curarization. However there are number of the circumstances limiting application of preparations of this group including it is related with rather high frequency of side effects and lack of efficiency at the deep neuromuscular block. Today in an arsenal of the anesthesiologist there was the latest chemical - sugammadex. Sugammadex realizes a new approach to restoration of the neuromuscular conductivity.

Reversal of moderate and intense neuromuscular block induced by rocuronium with low doses of sugammadex for intraoperative facial nerve monitoring

We report two cases in which moderate and intense rocuronium-induced neuromuscular block was reversed intraoperatively with low sugammadex doses in order to facilitate electromyographic evaluation of facial nerve function during surgery of the parotid gland and the middle ear. Acceleromyography was used to assess reversal of neuromuscular block before starting electromyography monitoring. Rocuronium-induced neuromuscular block was reversed with sugammadex 0.22mgkg(-1) when the TOF ratio was 0.14 in the first patient, and with sugammadex 2mgkg(-1) during intense block (PTC 0) in the second patient. In each case, appropriate neuromuscular function (TOF ratio≥0.9) was established soon after sugammadex administration, and electromyographic evaluation of facial nerve was successfully conducted. The use of rocuronium and sugammadex, coupled with objective neuromuscular monitoring with acceleromyography, assured complete restoration of neuromuscular function and created the optimal conditions for the surgical team.

[Analysis of difficult intubation factors in bariatric surgery. Influence of the choice of neuromuscular blocker on the availability of sugammadex]

OBJECTIVE

To determine the incidence of difficult tracheal intubation (DTI), as well as predictive factors for DTI and what influences the choice of the neuromuscular blocking agent (succinylcholine or rocuronium).

METHODS

This is an observational, prospective study on consecutive bariatric surgery patients. Tracheal intubation was performed by direct laryngoscopy with a preformed tracheal tube. DTI was considered when there was a Cormack-Lehane classification of iii-iv or when it was necessary to apply the DTI algorithm, which consisted in the use of Frova guide, and Airtraq video-laryngoscope as second choice, and finally awaking the patient and sugammadex reversal if rocuronium was the selected neuromuscular blocking agent. Thereafter, tracheal intubation was performed using an awake fibroscopic technique

RESULTS

One hundred and sixty six patients were included. In one case, conscious fiberscope tracheal intubation was performed. Succinylcholine was selected for 14 patients, and rocuronium for 151 patients. Fifteen patients had a DTI (9%): in 4 Airtraq was deemed necessary. One patient received sugammadex to reverse neuromuscular blockade. Conscious tracheal intubation represented 1.2% (95% CI; 0.3-4%). DTI was associated with Mallampati score of 3-4 (odds ratio, 3 [95% CI; 1.37-6.8], sensitivity of 33%, specificity of 91%) and with thyromental distance<6cm (odds ratio, 4.8 [95% CI; 1.45-16]; sensitivity of 53%; specificity of 79%).

CONCLUSION

Rescue airway protocol with Frova and Airtraq avoided the use of sugammadex, except in one patient.

A temporary decrease in twitch response following reversal of rocuronium-induced neuromuscular block with a small dose of sugammadex in a pediatric patient

We report a temporary decrease in twitch response following reversal of rocuronium-induced neuromuscular block with a small dose of sugammadex in our dose-finding study in pediatric patients. A 19-month-old female infant (9.6 kg, 80 cm) was scheduled for elective cheiloplasty surgery. Anesthesia was induced with nitrous oxide 50 % and sevoflurane 5 % and maintained with air, oxygen, sevoflurane 3 %, and fentanyl (total, 3 μg/kg). Neuromuscular monitoring was performed at the adductor pollicis muscle after induction of anesthesia but before the administration of rocuronium. Total dose of rocuronium during the surgery was 0.9 mg/kg. Neuromuscular block was reversed with 0.5 mg/kg sugammadex when one response was observed with post-tetanic count stimulation. Twitch responses after sugammadex administration showed a temporary decrease after its initial recovery. Maximum decreases in twitch responses were observed 17 min after initial dose of sugammadex. Twitch responses recovered to their control values after additional doses of 3.5 mg/kg sugammadex (4 mg/kg in total). Time from sugammadex administration to maximum decreases in twitch responses is earlier than has been reported in adults (20–70 min). It is demonstrated that following neuromuscular block reversal with insufficient dose of sugammadex, there is a possibility of the recurrence of residual paralysis within less than 20 min in pediatric patients.

Long-acting neuromuscular blocker use during prehospital transport of trauma patients

INTRODUCTION

The purpose of this study was to determine the rate of long-acting neuromuscular blocker (LA-NMB) use and evaluate the concurrent use of sedatives during prehospital care.

SETTING

Prehospital patients who were brought to a single emergency department in the United States.

METHODS

This was a retrospective cohort study of trauma patients who were intubated in the prehospital setting. The primary outcome measure was to determine the rate of LA-NMB use. The use of postintubation sedatives and the time to the administration of sedative agents was compared between patients who received an LA-NMB and those who did not.

RESULTS

A total of 51 patients were included in the final analyses. Overall, 82% (n = 42) of patients received an LA-NMB during transport. There was no difference in the rate of postintubation sedative use during transport between the LA-NMB and no LA-NMB groups (79% vs. 67%, respectively, P = .42). The LA-NMB group received sedatives less promptly after intubation compared with those who did not receive LA-NMBs (16 vs. 7 minutes, respectively; P = .04).

CONCLUSION

The use of LA-NMB is common during the prehospital transport of trauma patients. Some of these patients may not be given sedatives or may have delays in receiving sedatives after intubation.

[Rocuronium bromide as component of general anaesthesia in patients with traumatic cerebral compression]

The choice of myorelaxation agent for rapid sequence tracheal intubation for surgical cerebral decompression is a less studied question in neuroanaesthesiology. 32 patients with cerebral trauma (GCS<8) were involved in the study. Influence of succinylcholine and rocuronium bromide on cerebral circulation, intracranial pressure, cerebral perfusion pressure and systemic haemodynamics was assessed. Rocuronium bromide in dose 0.6 mg/kg provides good conditions for tracheal intubation in 40-60 seconds and does not influence on studied parameters. Rocuronium bromide is a drug of choice for general anaesthesia in patients with traumatic cerebral compression.

[Controlled myorelaxation in patients with aldosteroma]

Purpose of the study was to develop techniques of controlled myorelaxation during surgeries in patients with aldosteroma. 46 patients were involved in the study. Adrenalectomy was performed by videoendoscopy from retroperitoneal access. All patients were operated under general anaesthesia with sevoflurane with obligate monitoring of neuromuscular conduction (NMC). Patients were divided into 4 groups. Myorelaxation in patients of the group 1 (n = 14) was performed by continuous infusion of 0.4 mg/kg/hr rocuronium bromide (esmeron). Myorelaxation in patients of groups 2 (n = 11), 3 (n = 11) and 4 (n = 10) was performed by bolus administration of 0.15 mg/kg/hr esmeron. Patients of groups 1 and 2 were not decurarized. Decurarization in the group 3 was performed by proserin and in the group 4 by sugammadex. In patients of the group 1 esmeron consumption was minimal due to continuous infusion of the drug. Time of neuromuscular blockade recovery (TOF 0.9) was longer than 19 min. Worst data of neuromuscular blockade recovery accrued in the group 2. In patients of the group 3 time of neuromuscular blockade recovery (TOF 0.9) reduced 2.5-3 times in comparison with groups 1 and 2. The use of sugammadex in the group 4 provided almost 4.7 times faster neuromuscular blockade recovery than proserin administration. Controlled myorelaxation in patients with aldosteroma is possible when monitoring of neuromuscular conduction is provided. Infusion administration of esmeron provides decreasing of its consumption and high quality of myorelaxation. Sugammadex administration provides 4.7 times faster neuromuscular blockade recovery (TOF 0.9) than proserin administration without risk of neuromuscular block reverse.

Can ephedrine pretreatment be effective in alleviating rocuronium injection pain?

OBJECTIVE

The aim of this randomized, double-blind, placebo-controlled study was to evaluate the effect of ephedrine pretreatment on the intensity of rocuronium injection pain when rocuronium was applied by timing principle and also to compare this effect with lidocaine and placebo.

SUBJECTS AND METHODS

120 American Society of Anesthesiology risk score I-II patients scheduled for elective surgery under general anesthesia were randomized into three groups to receive either 70 μg/kg ephedrine (ephedrine group, n = 40) or 0.5 mg/kg lidocaine (lidocaine group, n = 40) or 5 ml NaCl 0.9% (placebo group, n = 40) as pretreatment. Thirty seconds after pretreatment drugs, rocuronium 0.6 mg/kg was administered by the timing principle and rocuronium injection pain scores were recorded. Twenty seconds after rocuronium administration, anesthesia was induced with thiopental and the patient's trachea was intubated. Hemodynamic parameters and adverse effects were recorded.

RESULTS

The overall frequency of having pain was 82.5, 52.5 and 22.5% in placebo, ephedrine and lidocaine groups, respectively. Although the frequency of mild and moderate pain scores was higher in the ephedrine group than in the lidocaine group, this difference was not statistically significant (p = 0.032 and p = 0.001, respectively).

CONCLUSION

Although not as effective as lidocaine 0.5 mg/kg, 70 μg/kg ephedrine pretreatment was able to alleviate rocuronium injection pain when rocuronium was applied by timing principle.

[Rocuronium vs vecuronium for neuromuscular block during transsternal thymectomy in the patient with myasthenia gravis]

BACKGROUND AND OBJECTIVES

Myasthenia gravis is an autoimmune disease marked by high titers of immunoglobulin G antibodies, which accelerate destruction of cholinergic receptors and interfere with neuromuscular transmission. This study aimed to determine whether neuromuscular function under a rocuronium block is different from function under a vecuronium block patients with myasthenia gravis and to describe extubation conditions in the operating room or the intensive care unit.

MATERIAL AND METHODS

Randomized, single-blind clinical trial enrolling patients with myasthenia gravis type IIa and IIb according to the classification of Osserman. The patients were randomized to groups receiving a vecuronium or rocuronium block. We recorded arterial oxygen saturation, capnogram, heart rate, noninvasive blood pressure, electrocardiogram, and neuromuscular function by accelerometry. During surgery 25% of the total dose of the neuromuscular blocking agent was administered. Maintenance was with a continuous infusion of propofol and fentanyl. All patients were extubated according to clinical criteria, confirmed by train-of-four ratio (T4/T1).

RESULTS

The mean (SD) time elapsed before recovery of 25% of neuromuscular function was 53.1 (1.9) min in the rocuronium group and 56.2 (0.8) min in the vecuronium group (P = .01). Time elapsed before recovery of 90% of function was 71.3 (2.7) min in the rocuronium group and 96.3 (1.2) min in the vecuronium group (P = .001). Twenty-eight of the 30 patients in the rocuronium group (93.3%) were extubated with recovery of 89.1% (0.5%) of twitch response and a T4/T1 ratio of 0.83. The difference between groups was statistically significant (P = .01). In no case was it necessary to administer a maintenance dose or reverse the block.

CONCLUSIONS

The rocuronium block had a better profile than the vecuronium block in this study. With this blocking agent we were able to circumvent respiratory depression, with its immediate consequences, and thus meet the main clinical criterion when anesthetizing patients with myasthenia gravis.

Peripartum anesthetic management of a patient with brittle cornea syndrome

Brittle cornea syndrome (BCS) is a rare autosomal recessive disease that affects the connective tissue. The syndrome is caused by genetic changes in the 4.7-Mb interval between the D16S3423 and D16S3425 markers on the 16q24 chromosome and mutations in the Zinc-Finger 469 gene (ZNF469). BCS is characterized by thin and fragile cornea that tends to perforate spontaneously or as a result of minor trauma to the eye. In addition, the patient usually suffers from hearing loss, mental retardation, hyperextensibility of skin and joints, as well as varying degrees of scoliosis. This phenotypical expression presents an interesting challenge to anesthetic care. We briefly present the perioperative management of a patient with BCS who underwent three cesarean sections.

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.

To asses the effects of rocuronium pretreatment on succinylcholine induced fasciculations and postoperative myalgias

OBJECTIVE

To asses the effects of Rocuronium pretreatment on Succinylcholine induced Fasciculations and postoperative Myalgias.

METHODS

A randomized double blind case control study was conducted in Department of Anaesthesia and Surgical Intensive Care Unit, Liaquat National Hospital, Karachi from October 2003 - April 2004. Sixty adults ASA I or II patients who presented for elective general surgical procedures were included in the study. The patients were divided in two groups of thirty each by a simple lottery method. Group "A" received placebo and group "B" received Rocuronium 0.1 mg/kg, one minute prior to induction with Pentothal Sodium 5 mg/kg, Suxamethonium, 1.5 mg/kg and Nalbuphine 10 mg / 70 kg. Fasciculations and intubation condition was assessed immediately after the induction of anaesthesia while post operative myalgias were assessed 6, 12 and 24 hours after surgery.

RESULTS

Fasciculations were noticed in group "A" as 100% (mild to severe) and in group "B" 13.3% (mild). Post operative myalgias at 6 and 12 hours after surgery were 76.66 % in group "A" and 16.66 in groups "B". After 24 hours in group "A' post operative myalgias were 93.33% and group "B" 23.33%.

CONCLUSION

It is concluded that pretreatment with Rocuronium reduced the incidence of myalgias, fasciculations and produced rapid precurarization in one minute thereby saving time on busy operating lists. They also allowed the early ambulation of patients in minor surgeries.

Relationship between depth of anesthesia and effect-site concentration of propofol during induction with the target-controlled infusion technique in elderly patients

BACKGROUND

There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion (TCI) induction in elderly patients. This study aimed to evaluate the relationship between effect-site concentration of propofol and depth of anesthesia during the TCI induction in elderly patients.

METHODS

Ninety patients (60 - 80 years) with an American Society of Anesthesiologists (ASA) physical status of 1 - 3, undergoing scheduled abdominal and thoracic surgery under general anesthesia were randomly allocated into one of three groups, Group S1, S2 and S3 (30 patients in each group). The patients in Group S1 received propofol with a target plasma concentration of 4.0 microg/ml; patients in Group S2 received propofol with an initial target plasma concentrations of 2.0 microg/ml that was raised to 4.0 microg/ml 3 minutes later; patients in Group S3 received an infused scheme of 3 steps; starting from a target plasma concentration of 2.0 microg/ml that was increased stepwised by 1 microg/ml until a target plasma concentration of 4.0 microg/ml was achieved, the interval between the two steps was 3 minutes. When an Observer's Assessment of Alertness/Sedation (OAA/S) score of 1 was achieved, remifentanil (effect-site concentration (Ce) of 4.0 ng/ml) and rocuronium 0.9 mg/kg were administered. Tracheal intubation was started 2 minutes after rocuronium injection. Changes of propofol Ce, blood pressure (BP), heart rate (HR), and bispectral index (BIS) were recorded.

RESULTS

When an OAA/S score of 1 was achieved, Ce of propofol were (1.7 +/- 0.4) microg/ml, (1.9 +/- 0.3) microg/ml, (1.9 +/- 0.4) microg/ml and the BIS values were 64 +/- 5, 65 +/- 8, and 62 +/- 8 in Groups S1, S2 and S3. Before intubation, Ce of propofol was (2.8 +/- 0.2) microg/ml, (2.8 +/- 0.3) microg/ml, (2.7 +/- 0.3) microg/ml, and the BIS values were 48 +/- 7, 51 +/- 7, and 47 +/- 5 in Groups S1, S2 and S3. By linear regression analysis, a significant correlation between Ce of propofol and BIS values was found (r = -0.580, P < 0.01). Systolic blood pressure (SBP) before intubation was significantly lower in Group S1 than in Groups S2 and S3. SBP and HR after intubation in the three groups were significantly increased when compared with pre-intubation values, but they did not exceed baseline values.

CONCLUSIONS

During the TCI induction, Ce of propofol with (1.9 +/- 0.3) microg/ml may make the elderly patients unconscious. When remifentanil with a Ce of 4.0 ng/ml is added a Ce of propofol with (2.8 +/- 0.3) microg/ml is suitable for intubation. The Ce of propofol has a close correlation with the BIS values. Also, a two-step TCI technique seems to be a more suitable method of anesthesia induction in elderly patients compared with the no-stepwise TCI technique and three-step TCI technique.

Doing What I Like

I have spent my entire professional life at Harvard Medical School, beginning as a medical student. I have enjoyed each day of a diverse career in four medical subspecialties while following the same triad of preclinical areas of investigation—cysteinyl leukotrienes, mast cells, and complement—with occasional translational opportunities. I did not envision a career with a predominant preclinical component. Such a path simply evolved because I chose instinctively at multiple junctures to follow what proved to be propitious opportunities. My commentary notes some of the highlights for each area of interest and the mentors, collaborators, and trainees whose counsel has been immensely important at particular intervals or over an extended period.

[Myoplegia with rocuronium bromide in children]

This study has evaluated the efficacy and safety of different doses of Esmerone in children under fluorothane anesthesia. It enrolled 85 children from a senior age group (7-14 years). According to the myorelaxant used, all the patients were divided into 2 groups: S and R. In the S group (n=25), myoplegia was carried out administering succinylcholine in a dose of 1 mg/kg. In the R group, myorelaxation was achieved using rocuronium bromide (Esmerone). According to the dose used, the group was divided into 3 subgroups, each comprising 20 patients. The initial dose of Esmemrone was 0.3, 0.6, and 0.9 mg/kg, respectively. The efficacy of the agent was evaluated by accelerographic and clinical data. The study has demonstrated that Esmerone was safer than succinylcholine. Increasing the dose (0.3-0.6-0.9 mg/kg) of Esmerone advantages in the onset of NMB and shows an increase in the duration of its action.

[To reduce drug expenditure in the operating room (OR)--a paradigm]

BACKGROUND

The main advantages of pharmacy controlled IV preparations (CIVAS) are reduced expenditures, contaminations, and human errors. Today, IV preparations by physicians in the operating room (OR) are based on axioms such as: purchased drugs have standard dosages, IV are prepared immediately before operation, quantity of drug used is unpredictable due to patient's body weight and type of operation and opened injections can't be used for different patients and operations. Due to those limitations, the quantities of drugs used are significantly lower than supplied and wastage cost is high.

AIM

To optimize CIVAS and reduce drug expenditure, using techniques from management and engineering sciences.

METHOD

A model of optimization, based on credibility and prediction tests was used to analyze CIVAS. The model uses parameters such as number and type of operations, drugs and quantities/operation. It identifies wastage for each drug used (quantities and cost) and predicts optimal doses and quantities to be prepared.

RESULTS

Although wastage (quantities) ranged from 30-70%, wastage cost was attributed mainly to two drugs: rocuronium (72%) and propofol (13 %). The model predicts that preparation of three standard doses of rocuronium will allow a 52.7% cost saving from the OR's IV drug budget.

CONCLUSION

This optimization model can be applied in wards where wastage cost of IV drugs is high. It will indicate which standard doses of which drug should be prepared, that will enable lowest wastage with minimal addition of manpower.

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.

Targeting Ouabain- and Adducin-dependent mechanisms of hypertension and cardiovascular remodeling as a novel pharmacological approach

Essential hypertension is a heterogeneous multifactorial syndrome associated with a high cardiovascular risk. A multiple choice of antihypertensive drugs is available; however, a high individual variability to the antihypertensive therapy is still responsible for a modest reduction of the CV risk and not satisfactory control of blood pressure levels. The success of future hypertension treatment will depend upon the understanding of the genetic molecular mechanisms operating in subsets of patients, and the ability of new drugs to specifically correct such alterations. Two mechanisms, among others, are involved in determining the abnormalities of tubular Na(+) reabsorption observed in essential hypertension: the polymorphism of the cytoskeletal protein alpha-adducin and the increased circulating levels of endogenous ouabain (EO). Both lead to increased activity and expression of the renal Na-K pump, the driving force for tubular Na transport. Morphological and functional cardiovascular alterations have also been associated with adducin and EO. Rostafuroxin is a new oral antihypertensive agent able to selectively antagonize adducin and EO hypertensive and molecular effects. It is endowed with high potency and efficacy in reducing blood pressure and preventing organ hypertrophy in animal models representative of both adducin and EO mechanisms. At molecular level, in the kidney, Rostafuroxin normalizes the enhanced activity of the Na-K pump induced by adducin mutation and antagonizes the EO triggering of the Src-EGFr-dependent signaling pathway leading to renal Na-K pump, and ERK Tyrosin phosphorylation and activation. In the vasculature, it normalizes the increased myogenic tone caused by ouabain. A very high safety ratio and an absence of interaction with other mechanisms involved in blood pressure regulation, together with initial evidence of high tolerability and efficacy in hypertensive patients, indicate Rostafuroxin as the first example of a new class of antihypertensive agents designed to antagonize adducin and EO-hypertensive mechanisms. Currently, a phase II multicenter European clinical trial is ongoing for providing the proof of concept that such a compound is effective in the subset of patients where these two mechanisms are at work.

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.

Cisatracurium or rocuronium versus rocuronium-cisatracurium combination

The present report evaluates the incidence of pain on intravenous injection and the condition of tracheal intubation at one minute following the administration of cisatracurium or rocuronium versus rocuronium-cisatracurium combination. We studied 60 patients, ASA 1, aged 18-60 years, undergoing elective surgical procedures. The patients were randomly assigned to 3 groups who received intravenously either 0.15 mg/kg cisatracurium [2ED95], 0,6 mg rocuronium [2ED95] or a combination of 0.075 mg/kg cisatracurium [1ED95], plus 0.3 mg rocuronium [1ED95]. In the awake patients, the pain on injection of muscle relaxant was assessed on a four point scale (none, mild, moderate, severe). Administration of the relaxant was followed by 1-2 mg/kg of lidocaine and 2 mg/kg propofol. Orotracheal intubation was performed 60 seconds following the administration of the relaxant. The intubating conditions were assessed and rated as excellent, good, fair or poor. The administration of 2ED95 cisatracurium resulted in poor intubating conditions at 60s, without pain on injection. In contrast, the administration of 2ED95 rocuronium resulted in excellent or good intubating conditions at 60s associated with high incidence of pain on injection in most of the patients. However, the combination of 1ED95 cisatracurium with 1ED95 rocuronium provided similar intubating conditions to the 2ED95 rocuronium alone, associated with a significantly less pain on injection.

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.

A new antihypertensive agent that antagonizes the prohypertensive effect of endogenous ouabain and adducin

Endogenous Ouabain (EO) and Adducin enhance the Na-K pump function and play an important role in sodium homeostasis and blood pressure (BP) regulation. In the general population, plasma EO modulates BP either by inhibiting the prohypertensive effect of an excessive salt intake or counteracting the depressor action of normal-moderate salt intake. Almost 50% of hypertensive patients have increased circulating plasma levels of EO. EO has been associated both to left ventricular dysfunction and hypertrophy. A new antihypertensive agent, PST2238, (17beta-(3-furyl)-5beta-androstan-3beta, 14beta, 17alpha-triol a digitoxigenin derivative) able to selectively antagonize both the EO and adducin prohypertensive and molecular effects, has been developed. In hypertensive rats (MHS strain) carrying both adducin mutations and increased plasma EO and in ouabain-infused rats (OS), PST2238 lowers BP by normalizing the renal Na-K pump function. In OS rats, PST antagonized the cardiac and renal pro-hypertrophic ouabain effect associated to the activation of the Src-EGFr-ERK(1/2) signaling cascade. Phase 1 clinical studies demonstrated a high tolerability of PST2238. In a preliminary phase 2 study on 42 mild never-treated hypertensive patients, PST2238 given for 3 months at 0.5 mg/day, significantly reduced BP in subjects with moderate salt intake, implying that it may be selectively effective in conditions where EO plays a prohypertensive role. In conclusion, PST2238, because of its peculiar action mechanism, represents a new tool to disentangle the complex relationship between salt intake, genetic control of renal sodium handling and EO effect.

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.

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.

Emergency anaesthesia in a patient with Gordon's syndrome

Gordon's syndrome is a rare condition characterized by hypertension and hyperkalemia despite normal renal glomerular function. We report the administration of an anaesthetic to one such patient for an urgent surgical procedure. The patient's serum potassium was only marginally raised at the outset of the procedure. During surgery the serum potassium rose significantly, but responded to conventional management. Hyperkalaemia is a specific electrolyte disturbance that has numerous implications for the administration of an anaesthetic. Most importantly, there is a danger that further acute elevations may occur, caused by the surgery, the anaesthetic, or the condition itself

The intubating laryngeal mask airway: Rocuronium improves endotracheal intubating conditions and success rate

STUDY OBJECTIVE

To assess intubating conditions without neuromuscular blocking drugs, to determine the relation between the dose of rocuronium and the probability of achieving excellent or at least good (good or excellent) intubating conditions with the intubating laryngeal mask airway (ILMA), and finally, to determine the relationship between rocuronium use and the success rate of endotracheal intubation.

DESIGN

Prospective, randomized, double-blinded, placebo-controlled study.

SETTING

University-affiliated medical center.

PATIENTS

Sixty American Society of Anesthesiologists physical status I and II patients undergoing elective surgery.

INTERVENTIONS

Anesthesia was induced with propofol 2.5 mg/kg and fentanyl 1 microg/kg. One minute after loss of consciousness, patients received rocuronium 0.2 mg/kg or saline. In the rocuronium group, if intubating conditions were scored as poor, rocuronium dose in the next patient was increased by 0.05 mg/kg. If intubating conditions were scored as good, no change was made, but if conditions were scored as excellent, the dose was decreased by 0.05 mg/kg. One minute after rocuronium or saline administration, an ILMA was used to intubate the trachea. If intubation was unsuccessful, a second attempt was made using the ILMA.

MEASUREMENTS

We recorded intubating conditions and the success rate of tracheal intubation.

MAIN RESULTS

Without rocuronium, the probability of achieving at least good intubating conditions with the ILMA was 30%. A rocuronium dose of 0.2 mg/kg resulted in a probability of 80% to achieve at least good intubating conditions. Rocuronium significantly increased the success rate of the second intubation attempt.

CONCLUSION

To achieve good or excellent intubating conditions with the ILMA, a rocuronium dose lower than the standard intubating dose of 0.6 mg/kg can be used. Neuromuscular blockade increases the success rate of intubation if a second attempt is necessary.

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.

[Comparative assessment of rocuronium bromide and cysatracurium besylate used during endosurgical operations in children]

The authors have studied the effects of the muscular relaxants rocuronium bromide and cysatracurium besylate on neuromuscular conduction, respiration mechanics, and hemodynamics in 120 children during endosurgical operations. The paper comparatively assesses the muscular relaxants and the procedures of their use, which made it possible to ensure controlled and deep relaxation.

Unsuspected sublingual mass causing difficult intubation in an infant

A case is described of a difficult intubation in an infant presenting for cleft palate closure, due to an unsuspected sublingual mass. The report stresses the fact that multiple anomalies can coexist in an infant and contribute to difficult intubation through different mechanisms. Various airway management strategies are explored.

Early and late reversal of rocuronium with pyridostigmine during sevoflurane anaesthesia in children

This study investigated the effect of pyridostigmine administered at different levels of recovery of neuromuscular function after rocuronium during sevoflurane anaesthesia in children. Fifty-one patients aged 3 to 10 years, ASA physical status 1 or 2 were randomized to 4 groups: a spontaneous recovery group; or, reversal with pyridostigmine 0.25 mg/kg with glycopyrrolate 0.01 mg/kg at one of three times: 5 minutes after rocuronium administration; at 1% twitch height (T1) recovery; or at a 25% twitch height (T25) recovery. Anaesthesia was induced with thiopentone (5-7 mg/kg) and maintained with 2-3% sevoflurane and 50% nitrous oxide. Atropine (0.015 mg/kg) and, after calibrating the TOF-Watch, rocuronium (0.6 mg/kg) were then administered. Maximal block occurred 1.1+/-0.5 min (mean, SD) after rocuronium administration. In the spontaneous recovery group, the clinical duration (recovery to T25) was 40.1+/-8.8 min and the recovery index (time between T25 and T75) 19.9+/-9.8 min. Recovery to TOF >0.9 from the time of rocuronium administration was reduced by approximately 30% in the pyridostigmine groups compared to the spontaneous recovery group. There was no significant difference among the three pyridostigmine groups. When pyridostigmine was given at T1 or T25, the time from pyridostigmine administration to TOF >0.9 was shorter than for the group receiving pyridostigmine 5 minutes after rocuronium.

Rocuronium attenuates oculocardiac reflex during squint surgery in children anesthetized with halothane and nitrous oxide

BACKGROUND

The oculocardiac reflex (OCR) may be activated during squint surgery. The aim of this study was to test whether rocuronium 0.4 mg kg(-1) could reduce the frequency of OCR, and also whether a single dose of succinylcholine 1 mg kg(-1) could affect the frequency of OCR during anesthesia with halothane in a nitrous oxide/oxygen mixture.

METHODS

A total of 161 ASA I children, 3-10 years old, undergoing elective surgery of the medial rectus muscle (MRM) were randomly assigned to three groups. Group R (n = 51), received 0.4 mg kg(-1) of rocuronium intravenously before endotracheal intubation. Group S (n = 58) received 1 mg kg(-1) of succinylcholine. Group C (controls, n = 52) received no relaxant. Oculocardiac reflex was defined as a reduction in heart rate (HR) > or = 15% and/or the appearance of any other arrhythmias, during manipulation of the MRM. Analysis of variance (anova), chi-squared, Kruskal-Wallis, and Student's t-tests were used for statistical analysis; P< 0.05 was considered statistically significant.

RESULTS

In group R, OCR occurred in 15/51 (29%) of children, in group S in 31/58 (53%), and in group C in 23/52 (44%) (chi2 = 6.46, P = 0.049). In group R, the incidence of arrhythmias such as nodal rhythms, supraventricular and ventricular premature beats was 6%, compared with 22% in group S and 19% in group C (chi2 = 6.01, P = 0.040). However, there was no reduction in the occurrence of bradycardia (chi2 = 0.16, P = 0.924).

CONCLUSION

Rocuronium reduced the frequency of OCR, mainly by reducing the incidence of supraventricular and ventricular premature beats.

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.

[Safety and quality of myoplegia in different types of abdominal surgeries]

The efficiency of new non-depolarized myorelaxants, i.e. of rocuronium and cisatracurium, in abdominal surgery with general anesthesia (combined or total intravenous anesthesia) of 114 patients was evaluated clinically and accelerometrically. The use of the above drugs at 2 x ED95 was confirmed to ensure a high-quality myorelaxation in different surgery variations (laparoscopy or laparotomy). A lack of effect on the hemodynamics (according to continuous non-invasive monitoring) and release of histamine (according to radioimmunology assay) make it possible to use the myorelaxants in patients with concurrent cardiovascular disease and with burdened allergic history. A bigger degree of prognosticated effect duration is typical of cisatracurium versus rocuronium, whereas the latter is a myorelaxant of choice in case a fast trachea intubation is needed.