RETRACTED ARTICLE: Diltiazem-lidocaine combination for the attenuation of cardiovascular responses to tracheal intubation in hypertensive patients

Purpose

Hypertensive patients are prone to haemodynamic changes after laryngoscopy and tracheal intubation. This study was undertaken to compare the efficacy of a combination of diltiazem and lidocaine with that of each drug alone for suppressing the cardiovascular responses to trachéal intubation.

Methods

Sixty hypertensive patients (ASA II), defined as systolic blood pressure > 160 mmHg and/or diastolic blood pressure > 95 mmHg (World Health Organization), undergoing elective surgery received, in a randomized, double-blind manner, 0.3 mg·kg^?1 diltiazem, 1.5 mg·kg^?1 lidocaine, or 0.3 mg·kg^?1 diltiazem plus 1.5 mg·kg^?1 lidocaineiv (n = 20 of each) before the initiation of laryngoscopy. Anaesthesia was induced with 5 mg·kg^?1 thiopentoneiv, and tracheal intubation was facilitated with 2 mg·kg^?1 succinylcholineiv after precurarization with 0.02 mg·kg^?1 vecuroniumiv. Changes in heart rate (HR), mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before and at immediate, 1, 2, 3, 5 and 10 min after tracheal intubation.

Results

The inhibitory effects of diltiazem-lidocaine combination on cardiovascular responses to tracheal intubation was greater than those of diltiazem or lidocaine as a sole medicine (RPP; 10602 ± 1448 (combination)vs 11787 ± 1345 (diltiazem), 15428 ± 1756 (lidocaine), mean ± SD,P < 0.05).

Conclusion

Prophylactic therapy with diltiazem-lidocaine combination is more effective than diltiazem or lidocaine alone for attenuating the cardiovascular changes associated with tracheal intubation in hypertensive patients.     

Monitoring of vecuronium-induced neuromuscular block at the sternocleidomastoid muscle in anesthetized patients

Purpose

To assess the degree of neuromuscular block acceleromyographically at the sternocleidomastoid muscle.

Methods

Eighteen adult patients scheduled for air–oxygen–sevoflurane–fentanyl and epidural anesthesia were studied. In the patients, the right accessory nerve and the sternocleidomastoid muscle were stimulated and the contraction of the sternocleidomastoid muscle was evaluated acceleromyographically. Simultaneously, the response of the adductor pollicis muscle was measured electromyographically. Supramaximal stimulating current, degree of maximum neuromuscular block after vecuronium 0.1 mg/kg, and onset of or recovery from vecuronium-induced neuromuscular block were compared between the two muscles.

Results

The supramaximal stimulating current at the sternocleidomastoid muscle was significantly higher than that at the adductor pollicis muscle (54.8 ± 7.1 vs. 33.7 ± 10.3 mA, mean ± SD, P < 0.001). The onset of neuromuscular block at the sternocleidomastoid muscle did not significantly differ from that at the adductor pollicis muscle (214 ± 117 vs. 161 ± 87 s, P = 0.131). The degree of maximum neuromuscular block at the sternocleidomastoid muscle was significantly less than that at the adductor pollicis muscle (93.6 ± 3.1 vs. 99.2 ± 2.5%, P < 0.001). During recovery from neuromuscular block, T1/control and train-of-four ratio measured at the sternocleidomastoid muscle were significantly higher than those at the adductor pollicis muscle 10–30 and 40–120 min after vecuronium, respectively (P < 0.05).

Conclusion

The sternocleidomastoid muscle is more resistant to vecuronium than the adductor pollicis muscle. Recovery from neuromuscular block is faster at the sternocleidomastoid muscle than at the adductor pollicis muscle.     

Effect of manual in-line stabilization of the cervical spine in adults on the rate of difficult orotracheal intubation by direct laryngoscopy: a randomized controlled trial

Purpose

Although manual in-line stabilization (MILS) is commonly used during endotracheal intubation in patients with either known or suspected cervical spine instability, the effect of MILS on orotracheal intubation is poorly documented. This study evaluated the rate of failed tracheal intubation in a fixed time interval with MILS.

Methods

Two hundred elective surgical patients were randomized into two groups. In the MILS group, the patient’s head was stabilized in a neutral position by grasping the patient’s mastoid processes to minimize any head movement during tracheal intubation. In the control group, the patient’s head rested in an optimal position for tracheal intubation. A 30-sec period was allowed to complete tracheal intubation with a #3 Macintosh laryngoscope blade. The primary endpoint was the rate of failed tracheal intubation at 30 sec. Secondary endpoints included tracheal intubation time and the Cormack & Lehane grade of laryngoscopy.

Results

Patient characteristics were similar with respect to demographic data and risk factors for difficult tracheal intubation. The rate of failed tracheal intubation at 30 sec was 50% (47/94) in the MILS group compared to 5.7% (6/105) in the control group (P < 0.0001). Laryngoscopic grades 3 and 4 were more frequently observed in the MILS group. Mean times for successful tracheal intubation were 15.8 ± 8.5 sec and 8.7 ± 4.6 sec for the MILS and control groups, respectively (mean difference 7.1, CI_95% 5.0–9.3, P < 0.0001). All patients who failed tracheal intubation in the MILS group were successfully intubated when MILS was removed.

Conclusion

In patients with otherwise normal airways, MILS increases the tracheal intubation failure rate at 30 sec and worsens laryngeal visualization during direct laryngoscopy.     

Reversal of a rocuronium-induced grade IV anaphylaxis via early injection of a large dose of sugammadex

Aim

To report rapid recovery from grade IV rocuronium-induced anaphylaxis with a large dose of sugammadex administered early after the onset of symptoms.

Clinical features

A 22-yr-old female without relevant medical history developed an anaphylactic reaction within three minutes of rocuronium injection at induction of anesthesia for a routine cholecystectomy. During the first six minutes, she was unresponsive to usual treatment and her condition evolved to a grade IV anaphylaxis reaction despite a cumulated dose of epinephrine 0.7 mg. Sugammadex 14 mg·kg^?1, injected six minutes after rocuronium, resulted in total resolution of all manifestations of anaphylaxis within three minutes. The patient was discharged from hospital the next day. Allergy investigations confirmed rocuronium as the cause of anaphylaxis.

Conclusion

Very early administration of a large dose of sugammadex may be an effective treatment for rocuronium-induced anaphylaxis.     

The increases in potassium concentrations are greater with succinylcholine than with rocuronium-sugammadex in outpatient surgery: a randomized,multicentre trial

Background

Succinylcholine provides rapid onset of neuromuscular blockade and short duration of action, but its administration may be associated with hyperkalemia. Rocuronium is not known to increase potassium concentration, has fast onset of activity, and can be rapidly reversed by sugammadex. This study evaluated changes in plasma potassium concentrations in patients randomized either to rocuronium followed by sugammadex reversal or to succinylcholine in ambulatory surgery.

Methods

In this multicentre randomized active-controlled study, adult patients undergoing short surgical procedures in an outpatient setting received either rocuronium 0.6 mg·kg^?1 for intubation with sugammadex 4.0 mg·kg^?1 for reversal (n = 70) or succinylcholine 1.0 mg·kg^?1 with spontaneous recovery (n = 80). Blood potassium concentrations were assessed at baseline (before study drug administration) and at intervals up to 15 min after rocuronium, sugammadex, and succinylcholine.

Results

At the primary endpoint, five minutes post-administration, the changes in potassium concentrations from baseline were significantly smaller in patients treated with rocuronium than in those given succinylcholine [mean (SD): ?0.06 (0.32) vs 0.30 (0.34) mmol·L^?1, respectively; P < 0.0001]. At baseline, potassium concentrations were similar in both groups, but they were greater at two, five, ten, and 15 min after succinylcholine than after rocuronium (P < 0.0001) for all time points. After sugammadex administration, there were no significant changes in mean potassium concentration from the pre-rocuronium baseline. No adverse effects related to hyperkalemia were observed.

Conclusion

Succinylcholine was associated with a modest increase in potassium concentration; these changes were not seen after rocuronium or sugammadex (Clinical trial registration number: NCT00751179).     

The interaction of antiemetic dose of droperidol with propofol on QT interval during anesthetic induction

Purpose

We investigated the effect of low-dose droperidol on heart rate-corrected QT (QTc) interval and interaction with propofol.

Methods

Seventy-two patients undergoing upper limb surgery were included in this study. Patients were randomly allocated to one of three groups: group S (n = 24), which received 1 ml saline; group D1 (n = 24), which received 1.25 mg droperidol; or group D2 (n = 24), which received 2.5 mg droperidol. One minute later, fentanyl (3 μg/kg) was administered. Two minutes after fentanyl administration, anesthesia was induced using propofol (1.5 mg/kg) and vecronium. Tracheal intubation was performed 3 min after the administration of propofol. Heart rate, mean arterial pressure, bispectral index, and QTc interval were recorded at the following time points: immediately before the droperidol injection (baseline); 3 min after the saline or droperidol injection; 3 min after the propofol injection; and 2 min after tracheal intubation.

Results

Compared to baseline, the QTc interval in group S and group D1 was significantly shorter after propofol injection, but recovered after tracheal intubation. In group D2, the QTc interval was significantly prolonged after droperidol injection, but recovered after propofol injection, and was significantly prolonged after tracheal intubation.

Conclusions

We found that saline or 1.25 mg droperidol did not prolong QTc interval, whereas 2.5 mg droperidol prolonged the QTc interval significantly, and that propofol injection counteracted the prolongation of the QTc interval induced by 2.5 mg droperidol.     

Monitoring of neuromuscular blockade in one muscle group alone may not reflect recovery of total muscle function in patients with ocular myasthenia gravis

Purpose

We report on two patients with ocular myasthenia gravis who received rocuronium, followed later by sugammadex to reverse neuromuscular blockade. Recovery was monitored simultaneously at the adductor pollicis muscle (APM) and the corrugator supercilii muscle (CSM).

Clinical features

Two patients with ocular myasthenia gravis (case 1: 74 yr-old female, 54 kg; case 2: 71 yr-old male, 72 kg) were scheduled for surgery under general anesthesia. Neuromuscular blockade was induced with rocuronium 0.3 mg·kg^?1 after placing two separate monitors at the APM and the CSM, respectively. Additional doses of rocuronium 0.1-0.2 mg·kg^?1 were given to maintain neuromuscular blockade at fewer than two twitches at the APM during surgery. Train-of-four response at the CSM did not show recovery of the twitch after its initial disappearance. At the end of surgery, sugammadex was administered. Twitch height at the APM recovered to the control value in 12 min (case 1) and 13 min (case 2) after sugammadex administration; however, twitch height at the CSM took 26 min (case 1) and 14 min (case 2) to recover to the control value.

Conclusion

After rocuronium-induced paralysis in both patients with ocular myasthenia, spontaneous recovery and sugammadex-assisted recovery were slower at the CSM than at the APM. In patients without the disorder, CSM recovery is faster than APM recovery. Thus, in ocular myasthenia gravis, neuromuscular recovery at the APM may not reflect recovery of all muscles.     

Residual paralysis: a real problem or did we invent a new disease?

Purpose

Over the past three decades, many studies have shown a high proportion of patients in the recovery room with residual neuromuscular blockade after anesthesia. The purpose of this Continuing Professional Development module is to present the physiological consequences of residual paralysis, estimate the extent of the problem, and suggest solutions to prevent its occurrence.

Principal findings

Residual paralysis is defined as a train-of-four ratio (TOFR) < 0.9 at the adductor pollicis. While tidal volume and, to a lesser extent, vital capacity are well preserved as the intensity of blockade increases, the probability of airway obstruction, impaired swallowing, and pulmonary aspiration increases markedly as TOFR decreases. In recent studies, incidences of residual paralysis from 4-57% have been reported, but surveys indicate that anesthesiologists estimate the incidence of the problem at 1% or less. The decision to administer neostigmine or sugammadex should be based on the degree of spontaneous recovery at the adductor pollicis muscle (thumb), not on recovery at the corrugator supercilii (eyebrow). The most important drawback of neostigmine is its inability to reverse profound blockade, which is a consequence of its ceiling effect. When spontaneous recovery reaches the point where TOFR > 0.4 or four equal twitch responses are seen, reduced doses of neostigmine may be given. The dose of sugammadex required in a given situation depends on the intensity of blockade.

Conclusion

Careful monitoring and delaying the administration of neostigmine until four twitches are observed at the adductor pollicis can decrease the incidence of residual paralysis. The clinical and pharmacoeconomic effects of unrestricted sugammadex use are unknown at this time.     

Utility of the Aintree Intubation Catheter in fiberoptic tracheal intubation through the three types of intubating supraglottic airways: a manikin simulation study

Purpose

The purpose of this study was to examine the utility of the Aintree Intubation Catheter (AIC) with three types of supraglottic airway devices for tracheal intubation (ISGAs) using a manikin.

Methods

Participants were 21 anesthesiologists with more than 2 years of experience in clinical anesthesia. Three types of ISGAs were passed through the glottis: Fastrack-Single Use (FSU; size 4), air-Q (size 3.5), and i-gel (size 4). Participants attempted fiberoptic tracheal intubation with the ISGAs in random order. Success rate of tracheal intubation, intubation time, and collision with the glottis were recorded. Participants also evaluated the subjective difficulty of the entire intubation process and passing the tracheal tube through the glottis using a Visual Analogue Scale.

Results

The FSU required a significantly longer time for intubation compared with the other two ISGAs (p < 0.05). AIC use did not significantly improve the success rate of intubation or shorten intubation times for any of the ISGAs. However, there were significantly more collisions with the glottis without AIC use for the FSU and air-Q compared to when they were used with the AIC (FSU, p = 0.015; air-Q, p = 0.025).

Conclusion

Among the ISGAs tested, intubation took longer with the FSU, and the FSU had a higher failure rate than the other ISGAs. AIC significantly decreased the number of collisions with the FSU and air-Q. These findings suggest that the AIC is effective in reducing collisions with the tracheal tube and thus will reduce the risk of mechanical injury to the airway.     

A comparison of the Trachway intubating stylet and the Macintosh laryngoscope in tracheal intubation: a manikin study

Purpose

The Trachway intubating stylet (Trachway^®), when used by experienced anesthesiologists, has been shown to be effective for difficult airway management. We evaluated the efficacy of this intubating stylet for tracheal intubation in a manikin when used by experienced laryngoscopists with little experience using this device.

Methods

Thirty-eight nurse anesthesiologists intubated the trachea of a manikin (Laerdal Airway Management Trainer) with a Trachway intubating stylet or a Macintosh laryngoscope in easy and difficult laryngoscopy scenarios. The duration of the intubation attempts, success rates, dental trauma, and ease of use (0 = very easy; 10 = very difficult) were recorded. The primary endpoint was the duration of the successful tracheal intubation attempt in the difficult laryngoscopy scenario. Data are presented as means (SD).

Results

Both devices resulted in similar tracheal intubation performance in the easy laryngoscopy scenario. However, the Trachway intubating stylet provided shorter intubation times (20.8 ± 5.6 vs. 25.5 ± 7.3 s; p = 0.003) and easier intubations (2.4 ± 1.6 vs. 5.7 ± 1.8; p < 0.001) compared with the Macintosh laryngoscope in the difficult laryngoscopy scenario. All tracheal intubations were successful and no dental trauma was observed when using the Trachway intubating stylet.

Conclusion

We concluded that the Trachway intubating stylet, when used by novices, is effective in both easy and difficult laryngoscopy scenarios. In difficult laryngoscopy scenarios, this device provided faster, easier, and less traumatic intubation than the Macintosh laryngoscope.     

The effect of rocuronium, sugammadex, and their combination on cardiac muscle and diaphragmatic skeletal muscle cells

Purpose

Rocuronium has been associated with muscle weakness when administered in prolonged infusions. The effect of sugammadex and rocuronium together on muscle is unknown. In this study, we examined the effects of rocuronium and sugammadex, and the complex formed by these agents, on cardiac and diaphragmatic muscle cells.

Methods

Forty-two Sprague–Dawley male rats were divided into six groups. Group I received only rocuronium at a dose of 1 mg/kg and groups II and III received sugammadex alone at doses of 16 and 96 mg/kg, respectively. Groups IV and V received 1 mg/kg rocuronium plus 16 mg/kg sugammadex and 1 mg/kg rocuronium plus 96 mg/kg sugammadex, respectively. Group six was the control group and received only 0.9 % NaCl without any drug.

Results

Histopathological examination demonstrated that rocuronium and high doses of sugammadex accumulated in both cardiac and diaphragm muscle tissues. We also observed intense edema and degeneration in diaphragmatic and myocardial cells when the rocuronium-sugammadex complex was used. Rocuronium and sugammadex remain in the circulation for a long time and they may cause skeletal muscle myopathy, vacuolization, pyknotic nuclear clumps, and hypertrophy, and weaken the muscle fibers.

Conclusion

Rocuronium, sugammadex, and rocuronium–sugammadex complexes cause histopathological changes and immunoreactivity to calcineurin in muscle cells.     

Monitoring orbicularis oculi predicts good intubating conditions after vecuronium in children

Purpose

The aim of the study was to compare visual estimation of onset of neuromuscular blockade at both the adductor pollicis (AP) and the orbicularis oculi (OO) in children and to determine if monitonng the OO could predict good intubating conditions during vecuronium-induced neuromuscular blockade.

Methods

Thirty ASA I–II children (1.5–9 yr) were studied. Anaesthesia was induced with 6–8 mg · kg^?1 thiopentone. The ulnar nerve at the wrist and the temporal branch of the facial nerve were stimulated every 10 sec using train of-four (TOF) stimuli. Vecuronium. 0.15 mg · kg, was administered as a bolus. The responses at both the OO and the AP were evaluated visually. Patients were randomly divided into two groups. In the AP group (n = 15), the trachea was intubated when the AP was completely blocked. In the OO group (n = 15), intubation was performed when the OO was completely blocked. Intubating conditions were scored on a scale of 1 to 4.

Results

All the patients had complete blockade at both the orbicularis oculi and the adductor pollicis. In the two groups, time from injection of vecuronium to complete neuromuscular blockade was shorter at the orbicularis oculi than at the adductor pollicis, 1.5 ± 0.5 min vs 2.3 ± 0.7 min, respectively, (P < 0.05; mean ± SD) in the AP group, 1.7 ± 0.3 min vs 2.3 ± 0.8 min, respectively, in the OO group (P < 0.05). Intubating conditions were excellent in all patients except one. where it was rated as good. They did not differ between groups.

Conclusion

Following administration of 0.15 mg · kg^?1 vecuronium in children, monitoring of the OO can detect good intubating conditions 0.7 min earlier than with monitoring of the AP.     

Tracheal intubation during chest compressions using Pentax-AWS®, GlideScope®, and Macintosh laryngoscope: a randomized crossover trial using a mannequin

Background

A randomized crossover trial was conducted to compare the performance of two videolaryngoscopes (Pentax-AWS^®, GlideScope^®) with the Macintosh laryngoscope for tracheal intubation during continuous chest compressions on a mannequin.

Methods

Thirty-two inexperienced junior interns performed tracheal intubations on an advanced life support simulator with either a normal or difficult airway scenario. The sequence of intubating devices and airway difficulty were randomized. The following data were measured and recorded: time to complete tracheal intubation (primary end point), overall success rate, time to visualize the vocal cords, percentage of glottic opening, dental compression, and ease of intubation.

Results

With a normal airway, the times (median [interquartile range]) to complete tracheal intubation were shorter with the Pentax-AWS (12.1 [10.1-14.4] sec) and the GlideScope (14.3 [12.4-17.6] sec) than with the Macintosh laryngoscope (16.5 [13.1-22.1] sec) (P < 0.03 for both). The time difference between the two videolaryngoscopes was not statistically significant. With a difficult airway scenario, the times to complete tracheal intubation were 13.9 [10.9-20.4] sec, 19.2 [16.4-32.3] sec, and 30.1 [21.0-56.5] sec, respectively (P < 0.05 for all differences). The videolaryngoscopes were also more effective than the Macintosh laryngoscope with respect to secondary outcomes.

Conclusions

The two videolaryngoscopes were superior to the Macintosh laryngoscope in terms of performing tracheal intubation during continuous chest compressions on a mannequin. In a difficult airway scenario simulating cardiac arrest, the Pentax-AWS performed better than the GlideScope.     

Temporal variation of the leak pressure of uncuffed endotracheal tubes following pediatric intubation: an observational study

Purpose

Uncuffed endotracheal tubes are still preferred over cuffed tubes in certain situations in pediatric anesthesia. Inaccurately sized uncuffed endotracheal tubes may lead to inadequate ventilation or tracheal mucosal damage during anesthesia. Endotracheal tube size in children is usually assessed by measuring the audible leak pressure; if the fit of the tube and the leak pressure decrease significantly with time, reintubation during surgery as a result of inability to ventilate effectively may be challenging, and could lead to patient morbidity. There is no evidence to indicate whether leak pressure increases or decreases with time following endotracheal intubation with uncuffed tubes in children.

Methods

We measured leak pressure for 30 min following tracheal intubation in 46 ASA I children age 0–7 years after excluding factors known to modify leak pressure.

Results

The largest mean change in leak pressure occurred between time points 0 and 15 min, an increase of 3.5 cmH₂O. Endotracheal tube size and type of procedure were associated with the leak pressure. In the final linear mixed model, there were no statistically significant variations in leak pressure over time (P = 0.129) in this group of children.

Conclusions

We did not identify a consistent change in leak pressure within 30 min following tracheal intubation with uncuffed endotracheal tubes in this group of children.     

Comparaison de l’Airtraq, du X-Lite et du laryngoscope standard pour la chirurgie thyroïdienne: une étude clinique randomisée

Purpose

To compare the performance of the Airtraq, X-Lite, and direct laryngoscopes for tracheal intubation for elective thyroid surgery.

Methods

In this randomized prospective study, Patients who were ASA (American Society of Anesthesiologists) I or II physical status I or II and patients undergoing thyroid surgery were included in this randomized prospective study. Patients with attributes for difficult intubation criteria were excluded. After induction of anesthesia with fentanyl, propofol, and cisatracurium, patients were randomized into three groups according to the intubating device used: Airtraq laryngoscope (Airtraq), X-Lite video laryngoscope (X-lLite), and direct laryngoscope with a Macintosh blade (Direct). The primary outcome measurement was the time needed for tracheal intubation. Secondary outcomes included intubation difficulty score (IDS), Cormack-Lehane classification, as well as hemodynamic and respiratory effects.

Results

One hundred and five patients were included. Mean (standard deviation) time for intubation was 28.2 (2.1) sec in the Airtraq group vs 36.6 (3.7) sec in the X-Lite group (P < 0.001), and 41.1 (4.4) sec in the Direct group (P < 0.001). Compared with to the direct laryngoscope, the Airtraq provided better visualization of the glottis (P = 0.003) with fewer attempts (P < 0.001) and lower IDS (P < 0.001). The intubation difficulty score was lower with the Airtraq than with the X-Lite (P = 0.003). Patients in the X-Lite and Direct groups showed more hemodynamic variations than those in the Airtraq group. There was only one failed intubation, in the direct group.

Conclusion

In thyroid surgery, the Airtraq and X-Lite laryngoscopes decrease time to intubation when compared with direct laryngoscopy.     

Intubation time required for tracheal intubation with low-dose rocuronium in children with and without atropine

Purpose

The purpose of this study was to determine the intubation time needed to facilitate tracheal intubation (Time_EI) with a low dose of rocuronium (0.3 mg/kg) during propofol induction, and to determine whether this time was reduced by the administration of atropine.

Methods

Forty-six children, aged 3–10 years, were randomly assigned to receive either saline (control group) or atropine 10 μg/kg (atropine group). Anesthesia was induced with alfentanil 10 μg/kg, propofol 2.5 mg/kg, and rocuronium 0.3 mg/kg. Each Time_EI at which tracheal intubation was attempted was predetermined according to the up-and-down method. The values of Time_EI that provided excellent intubation conditions in 50 and 95 % of patients were defined as Time_EI50 and Time_EI95, respectively.

Results

Time_EI50 ± SD was 160 ± 26.2 and 150 ± 13.7 s in the control and atropine groups, respectively. Using isotonic regression, Time_EI95 in the control and atropine groups was 199 s (95 % CI 198.8–200.7 s) and 171 s (95 % CI 171.3–172.1 s), respectively. Time_EI95 was significantly higher in the control group than in the atropine group (P < 0.001). HR was significantly higher in the atropine group than in the control group during the study period.

Conclusions

This study demonstrated that the Time_EI95 of a low dose of rocuronium (0.3 mg/kg) required for excellent tracheal intubation was 199 s during i.v. anesthesia induction using propofol and alfentanil in children. Also, i.v. atropine (10 μg/kg) before anesthesia induction was able to reduce Time_EI95 by 28 s.     

Hydrocortisone reduces postoperative shivering following day care knee arthroscopy

Purpose

Postoperative shivering is commonly observed in patients after general anesthesia. A double-blind randomized controlled trial was conducted in patients undergoing day care knee arthroscopy to test the hypothesis that a single intraoperative dose of hydrocortisone would prevent or attenuate postoperative shivering.

Methods

One hundred and twenty patients were given a nitrous oxide-isoflurane-remifentanil anesthetic. Approximately ten minutes before the end of anesthesia, they were randomized to receive normal saline (Control group; n = 40); hydrocortisone 1 mg·kg^?1 iv (Hydrocortisone-1 group; n = 40), or hydrocortisone 2 mg·kg^?1 iv (Hydrocortisone-2 group; n = 40). Postoperative shivering was graded by a blinded observer using a five-point scale: Grade 0: none; Grade 1: one or more areas of piloerection but without visible muscular activity; Grade 2: visible muscular activity confined to one muscle group; Grade 3: same as Grade 2 but in more than one muscle group; and Grade 4: gross muscular activity involving the entire body.

Results

Shivering (Grades 1-4) was observed in 33 patients (82%) in the Control group, 13 patients (32%) in the Hydrocortisone-1 group (P < 0.001 compared with the Control group), and eight patients (20%) in the Hydrocortisone-2 group (P < 0.001 compared with the Control group). The overall incidence of shivering was similar in the Hydrocortisone-1 and Hydrocortisone-2 groups.

Conclusions

This study shows that hydrocortisone (1-2 mg·kg^?1 iv) provides effective prophylaxis against postoperative shivering in patients undergoing day care knee arthroscopy under general anesthesia.     

Monitoring masseter muscle evoked responses enables faster tracheal intubation

Purpose  

The aim of this study was to investigate whether monitoring neuromuscular block at the masseter muscle (MM) would allow faster tracheal intubation when compared with that at the adductor pollicis muscle (APM).     

Cricoid pressure with the Truview Evo2TM laryngoscope improves the glottic view

Objective

The Truview Evo2? laryngoscope blade is designed to improve glottic view. This study was designed to evaluate the effect of cricoid pressure (CP) on laryngeal view and the ease of orotracheal intubation with the Truview Evo2 laryngoscope.

Methods

In this randomized controlled trial, 50 patients (American Society of Anesthesiologists physical status I-II, aged 18 to 60 yr) scheduled for elective surgery were enrolled. After induction of anesthesia and muscle paralysis, laryngoscopy was performed using the Truview Evo2^TM laryngoscope with the patient’s head in the neutral position. In Group 1, the percentage of glottic opening (POGO) score was evaluated first without CP, then with CP, and CP was applied for intubation. In Group 2, the POGO score was evaluated first with CP, then without CP, and no CP was applied for intubation. Time to intubation and number of attempts required for intubation were also recorded.

Results

In 50 patients, the mean (standard deviation) POGO view obtained with the application of CP was 93% (10%) compared with 81% (19%) in patients without CP (P < 0.01). Times to intubation were similar in the two groups: 14.2 (6.6) sec vs 14.0 (9.3) sec in Groups 1 and 2, respectively (P = 0.924). Sixteen percent of patients in Group 1 required a second attempt at tracheal intubation, while only 4% of patients in Group 2 required a second attempt (P = 0.162).

Conclusion

When using the Truview Evo2^TM laryngoscope with the patient’s head in the neutral position, application of CP improves the glottic view. This approach is not associated with increased difficulty in intubation.     

Uso de sugamadex pelo peso corporal ideal versus corrigido em 20% e 40% em cirurgia bariátrica – ensaio clínico randômico e duplo‐cego

Background and objectives

The weight parameters for use of sugammadex in morbidly obese patients still need to be defined.