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At least 1,261 records · Page 70Linked to original sources
PubMed2005

Osteolysis after total knee arthroplasty: influence of tibial baseplate surface finish and sterilization of polyethylene insert. Findings at five to ten years postoperatively.

BACKGROUND: Debris displaced from the articular and backside surfaces of the polyethylene inserts of modular tibial components is considered a chief cause of osteolysis at the sites of total knee arthroplasties. One design of total knee replacement featured changes, over time, in the proximal surface roughness of the tibial baseplate and the method of sterilization of the polyethylene insert. We hypothesized that polishing the baseplate surface and sterilizing the insert with means other than gamma radiation in air had reduced the prevalence of osteolysis. METHODS: Three hundred and sixty-five posterior cruciate ligament-retaining Anatomic Modular Knee primary total knee arthroplasties were performed in 300 patients from 1987 to 1998. Anteroposterior and lateral radiographs of the knees were made within a five to ten-year postoperative interval. Two arthroplasty specialists independently examined the radiographs for evidence of osteolysis (defined as any nonlinear region of cancellous bone loss with delineable margins). RESULTS: Osteolysis was identified in 34% (eighty-two) of 242 knees treated with an insert that had been gamma-irradiated in air and affixed to a rough baseplate surface, and it was identified in 9% (nine) of ninety-eight knees treated with an insert that had been gamma-irradiated in an inert gas, or had not been irradiated, and joined to a polished surface. Osteolysis was associated with six factors, including one related to the patient (male gender), one related to the tibial baseplate (the proximal surface finish), three related to the polyethylene insert (the material from which it was machined, the sterilization method, and the shelf age), and one related to the technique (hyperextension of the femoral component relative to the tibial component). CONCLUSIONS: In this design of a total knee prosthesis, polishing the tibial baseplate counterface and implementing a more contemporary sterilization practice (as opposed to gamma radiation in air) noticeably diminished but did not eliminate osteolysis.

Aged↗
PubMed1993

Treatment of lower extremity injuries with orthotic shoe inserts. An overview.

Orthotic shoe inserts are very effective in providing symptomatic relief of lower extremity complaints in running athletes. Inserts adjust the biomechanical-variables associated with running injuries and reduce the effect of high stresses produced by running activities. Orthotic treatment is based on an understanding of complex coupling of rotation of the lower extremity with pronation and supination of the subtalar joint. Orthotic fabrication is initiated by determining the neutral position of the foot and obtaining an accurate cast of this position. Successful treatment with orthotic shoe inserts is dependent on careful evaluation of the runner and formulation of a properly fitted orthosis. When correctly utilised, orthotic shoe inserts are beneficial for a broad range of disorders experienced by runners. Since biomechanical deficits may be related to injuries along the entire lower extremity, specific diagnoses may be of lesser indication; however, accurate identification of the underlying biomechanical deficit is critical. Problems related to excessive or prolonged pronation are most amenable to orthotic treatment. While treatment of the cavus foot with orthotic shoe inserts is sometimes worthwhile, the clinician should be aware of limited success in this instance. Finally, orthotics are only one facet in the overall treatment plan for injured running athletes. Most overuse syndromes will respond to rest, training modification, and a change in the running surface or shoe. Equally important is the use of a proper conditioning and stretching programme both for injury prevention and for treatment of specific injuries. Treatment with orthotic shoe inserts should not be used as a substitute for any of these approaches.

Athletic Injuries↗
PubMed2006

[Mobility of B.C.T. dental implants inserted by one- and two-phase surgical method--an experimental study].

BACKGROUND/AIM: Achievement of the osseointegration of dental implants is of crucial importance for their long-term survival. One of the factors that influence the osseointegration is a surgical method of implantation. The outcome of osseointegration can be evaluated on the basis of implant mobility in bone. The aim of this study was to investigate and compare the mobility of B.C.T. dental titanium implants inserted to experimental animals using an one- and two-phase method. METHODS: The investigation was performed using a split-mouth design on nine dogs, male german shephards, average age of 3.5 years and average weight of 32 kg. Extractions of the third and fourth lower premolars were performed under intravenous (i.v.) anaesthesia with 5% ketamine chloride. Eight weeks after the extractions, the implants, diameter of 4.5 mm each, with four threads 13.7 mm long, were inserted. Eighteen implants were inserted one side of the jaw using a one-phase method, and another 18 implants were inserted contralaterally using a two-phase method. Three months after the implantation, the implant mobility was evaluated. Three measurements were performed with a Periotest device, and average values were calculated. The implant mobility was classified according to the Periotest scale in four groups of Periotest values (PTV) and compared. A total of 36 implants were inserted in 9 experimental dogs. The PTV ranged from -7.666 to + 50. RESULTS: According to the Periotest scale, 14 one-phase implants (78%) were classified into the 0 group of PTV, and 4 one-phase implants (22%) in the 3rd group. Thirteen two-phase implants (72%) were classified in the 0 group, and 5 implants in the 3rd group of Periotest scale. The difference in the average values of PTV between the two methods was 0.879 which was not statistically significant. CONCLUSION: This study showed that the method of implant insertion had no influence on the implant mobility, i.e. satisfactory osseointegration could be achieved by both methods. Further clinical parameters, as well as pathohistological and histomorphometric ones, have to be evaluated in order to assess better outcome of a particular method.

Animals↗
PubMed1989

Molecular and clinical characterization of an insertional polymorphism of the insulin-receptor gene.

A restriction-fragment-length polymorphism (RFLP) detected with the human insulin-receptor cDNA and the enzyme Sac I has been reported to be associated with non-insulin-dependent diabetes mellitus (NIDDM) in White and Black populations and segregated with diabetes in two small pedigrees with maturity-onset diabetes of the young. A size difference of approximately 500 base pairs (bp) was demonstrated between the alleles of this and several other RFLPs that mapped to the same 300-bp region near the transmembrane coding region of the cDNA beta-chain, thus suggesting the presence of an insertion in this region that could affect insulin-receptor function. Genomic DNA fragments containing this RFLP were cloned from an individual heterozygous for the putative insertion, and the differing fragments of the two alleles were sequenced. The presence of a 400-bp insertion was thus confirmed and was demonstrated to be entirely within an intron. No significant coding-region differences from published cDNA sequences were detected in four exons sequenced from the region of the insertional allele. The sequenced regions included multiple Alu repeat sequences. The RFLP was unusual in that the larger allele consisted of an additional Alu repeat sequence that included a new Pst I site. Because the nature and location of the insertion did not suggest a role in insulin-receptor function, the association of this RFLP with NIDDM and hyperinsulinemia was reexamined in a small sample of Whites. No association could be demonstrated, and the insertion also failed to segregate with NIDDM in five White pedigrees.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1988

Feed intake and digestion by beef steers consuming and receiving ruminal insertions of prairie hay differing in level and particle size.

A 5 X 5 Latin square design involving five cannulated beef steers (342 and 358 kg avg initial and final body weights, respectively) fed prairie hay (76.7% neutral detergent fiber, 5.7% acid detergent lignin and .85% N) was conducted to evaluate effects on feed intake and nutrient digestion of variations in physical characteristics of ruminal digesta achieved by ruminal insertion of different amounts of prairie hay differing in particle size. Steers were fed hay ad libitum in two equal meals (0800 and 2000). At 1200, four of the steers received manual, ruminal insertions of ground hay. Fine hay (F) was ground through a screen with 2-mm openings (.39 mm mean particle size), whereas coarse hay (C) was ground through a screen with 2.54-cm openings (4.46 mm mean particle size). Amounts of hay inserted were .2 (low, L) or .4% (high, H of initial body weight of individual steers. Ruminal hay insertions comprised 18% of total dry matter (DM) intake for L and 34 and 37% for HF and HC, respectively. Fed hay consumption decreased (P less than .05) with hay insertion and was lower for H than L; total DM intake was not influenced by treatment (P greater than .10). Ruminal NH3-N concentrations and ruminal organic matter digestion was greater (P less than .05) with ruminal hay insertion than without and with H than with L (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMedDate not supplied

Prediction of heating patterns of a microwave interstitial antenna array at various insertion depths.

Measurements made on the interstitial microwave antennas used for hyperthermia cancer therapy indicate that the heating patterns vary with the insertion depths (defined as the distance from the antenna tip to air-tissue interface). The antennas are made of thin coaxial cables with a radiation gap or gaps on the outer conductor. The antennas are inserted into small polypropylene catheters implanted in the tumour volume. This type of antenna may be simulated as an asymmetric dipole with one arm being the tip section consisting of the expanded extension of the inner conductor, and the other arm being the section of the outer conductor from the gap to the insertion point (air-tissue interface). We use four of the antennas to form a 2 cm x 2 cm array. The antennas are positioned on the corners of a 2 cm square. Measurements on both single antennas and multi-antenna arrays show that the maximum heating is not stationary with position along the antenna when the depth of insertion is changed. This paper investigates the theoretical prediction of the changes in heating patterns of interstitial microwave antennas at different insertion depths. Each of the antennas in the array is simulated as an asymmetric dipole. The SAR (specific absorption rate) is computed by using the insulated dipole theory. The temperature distribution in absence of perfusion is obtained through a thermal simulation routine to convert the SAR pattern into the temperature pattern. Excellent qualitative agreement is found between the theoretical heating pattern and the measured pattern in a non-perfused phantom on a 2 cm x 2 antenna array. Since the insertion depths of the interstitial antennas are different from patient to patient, it is recommended that simulation of the heating be done before treatments, to confirm the delivery of power to the target region.

Biomedical Engineering↗
PubMedDate not supplied

Three-dimensional theoretical SAR and temperature distributions created in brain tissue by 915 and 2450 MHz dipole antenna arrays with varying insertion depths.

Theoretical three-dimensional power deposition and temperature distributions were calculated for interstitial hyperthermia microwave antenna arrays driven at 915 and 2450 MHz in brain tissue. Four dipole antennas were assumed to be placed in a 2 x 2 cm array with varying insertion depths in cylindrical tumour models. The bioheat transfer equation was solved for the three-dimensional steady-state temperature distributions using a finite element method. Homogeneous and non-homogeneous blood flow models were considered. As a basis of comparison of the various temperature distributions, the volume of the tumour heated to greater than or equal to 43 degrees C was calculated. SAR distributions calculated for the 915 MHz antenna arrays in brain tissue were very similar to those calculated for muscle. The 2450 MHz arrays showed similar behaviour to the 915 MHz arrays; however, as the insertion depth increased from slightly less than a full-wavelength there was a single hotspot centred at the antenna junction. For the 2450 MHz arrays, the predicted therapeutic tumour volumes were relatively constant over the entire range of insertion depths considered, and in fact, for most insertion depths considered, the model predicted the 2450 MHz arrays would heat larger therapeutic volumes than the 915 MHz arrays. For the 915 MHz array, at insertion depths between 7.8 and 14.6 cm there was a sharp decrease in the predicted therapeutic volume due to a proximal secondary hotspot in the normal tissue causing overheating. However, when the same size tumour at the same insertion depth was heated with the 2450 MHz array, the hotspot was in the tumour, adding to the volume of tumour that was heated to therapeutic temperatures.

Body Temperature↗
PubMed1994

Immune responses to epitopes inserted in Salmonella flagellin.

Plasmid pLS408 includes gene fliC(d) specifying Salmonella flagellin of antigenic type d with an in vitro deletion of a 48 base-pair EcoRV fragment in its central hypervariable antigenically-determinant region IV. Oligonucleotides specifying peptide epitopes of antigens of unrelated pathogens inserted, in correct orientation, at the unique EcoRV site of pLS408 specify chimeric flagellins and, in many instances, cause production of functional flagella when the plasmid is placed in a flagellin-deficient delta aroA live-vaccine strain of Salmonella dublin. The foreign epitope is then exposed at the surface of the flagellar filaments, as shown by the immobilizing effect of anti-epitope antibody and by immunogold electron-microscopy. The live-vaccine strain with a foreign epitope at the surface of its flagella when administered to mice by injection nearly always causes production of antibody with affinity for the foreign epitope and, sometimes, also for the source protein. Repeated injection of the live vaccine with an epitope of Streptococcus pyogenes type 5 M protein as insert caused production of opsonizing antibody and conferred partial protection against Streptococcus challenge. Injection of semi-purified chimeric flagella or flagellin, alone or with adjuvant, likewise causes antibody production, in one instance sufficient to give partial protection against influenza A virus challenge. Plasmid pLS408 with some inserts does not confer motility, either because the filaments produced are non-functional or because flagellin is made but not assembled or because little or no flagellin is produced. The features of a sequence which as insert determine production or non-production of functional flagella are not known. The effect of insertion of known T-cell epitopes and cellular immune responses to epitope inserts in flagellin are as yet little explored.

Animals↗
PubMed2006

Technical note: development of a tool to insert abomasal infusion lines into dairy cows.

A tool was developed to aid in ruminal insertion of abomasal infusion lines into dairy cows. The tool consisted of 2 pieces cut from polyvinyl chloride pipe. The first piece of pipe, the insertion tool, contained a groove that held the flexible plastic flange that is on the end of the infusion line. The insertion tool containing the flange was inserted into the ruminal cannula, through the sulcus omasi, and into the abomasum. The second piece of pipe, the delivery tool, was threaded through the insertion tool, and it was used to dislodge the flange from the insertion tool and into the abomasum.

Abomasum↗
PubMed2006

Reproduction in dairy cows following progesterone insert presynchronization and resynchronization protocols.

The objectives of this study were to evaluate the effects of an intravaginal insert containing progesterone (CIDR, controlled internal drug releasing) administered in presynchronization and resynchronization protocols on cyclicity, detection of estrus, pregnancy rate, and pregnancy loss to first AI; reinsemination patterns; and pregnancy rates to second postpartum AI before and after the time of first-service pregnancy diagnosis in dairy cows. Holstein cows (n = 1,052) were blocked by parity and BCS at 3 +/- 3 d in milk (study d 0 = day of calving) and assigned randomly to 1 of 3 presynchronization treatments. During the presynchronization programs, all cows received 2 injections of PGF2alpha, on study d 35 and 49. Cows enrolled in the control presynchronization treatment received AI after detected estrus from study d 49 to 62. Cows enrolled in the CIDR estrus-detection (CED) presynchronization treatment received a CIDR insert from study d 42 to 49 and AI on detection of estrus from d 49 to 62. Cows enrolled in the CIDR timed AI (CTAI) presynchronization treatment received the same treatment as CED, but were subjected to timed AI on study d 72 after the Ovsynch (GnRH, 7 d PGF2alpha, 2 d GnRH, 24 h timed AI) protocol. The control and CED cows not inseminated by study d 62 were enrolled in the Ovsynch protocol on the same day and received timed AI on study d 72. After first AI, cows were assigned to no resynchronization (RCON) or resynchronization with a CIDR insert (RCIDR) between 14 and 21 d after AI. Blood samples collected on study d 35, 49, and 62 were analyzed for concentrations of progesterone and cows were classified as anestrous when progesterone was < 1.0 ng/mL in the first 2 samples. On study d 62, anestrous cows with progesterone > or = 1.0 ng/mL were classified as having resumed cyclicity. Pregnancy was diagnosed at 31 and 60 d after first AI and at 42 d after second AI. A greater proportion of anestrous cows in CED and CTAI became cyclic by d 62 postpartum than control cows. Resynchronization with the CIDR insert increased the pregnancy rate at 31 d after first AI in CED and CTAI, and at 60 d after AI in all cows because of reduced pregnancy loss. These results indicate that presynchronization with the CIDR insert increased induction of cyclicity in anestrous cows and that resynchronization with the CIDR insert did not affect the reinsemination rate but did reduce pregnancy loss and increased the pregnancy rate at 60 d after first AI.

Administration, Intravaginal↗
PubMed2001

Effect of insertion torque on bone screw pullout strength.

The effect of insertion torque on the holding strength of 4.5-mm ASIF/AO cortical bone screws was studied in vitro. Screw holding strength was determined using an Instron materials testing machine (Bristol, United Kingdom) on 55 lamb femora and 30 human tibiocortical bone sections. Holding strength was defined as tensile stress at pullout with rapid loading to construct failure. Different insertion torques were tested, normalizing to the thickness of cortical bone specimen engaged. These represented low, intermediate, high, and thread-damaging insertion torque. All screws inserted with thread-damaging torque and single cortex engaging screws inserted to high torque tightening moments showed diminished holding strength. This loss of strength amounted to 40%-50% less than screws inserted with less torque.

Biomechanical Phenomena↗
PubMedDate not supplied

High-pressure trocar insertion technique.

BACKGROUND: The majority of laparoscopic complications occur at the time of Veress needle and trocar insertion. Although not very frequent, they increase the morbidity and mortality of both diagnostic and operative laparoscopic procedures. Alternative techniques of trocar insertion have been described but have not completely eliminated the risk of injury. TECHNIQUE: After Veress needle insertion and establishment of pneumoperitoneum to 25 to 30 mm Hg, insertion of a short trocar is performed in the deepest part of the umbilicus without elevation of the anterior abdominal wall. The result is a parietal peritoneal puncture directly beneath the umbilicus. The high-pressure setting used during initial insertion of the trocar is lowered as soon as safe abdominal entry is documented. EXPERIENCE: The trocar insertion technique described above was performed in 3041 procedures. No vascular injury occurred. There were two bowel perforations. No complications related to the increased intra-abdominal pressure were observed. CONCLUSION: The high-pressure abdominal entry technique has the advantage of reducing intra-abdominal trocar-related injuries without requiring additional instrumentation or additional training.

Humans↗
PubMed1998

[The morphometric study of endometrial spiral arterioles before and after insertion of gamma CuI and TCu 220C intrauterine devices].

OBJECTIVE: To investigate the morphologic changes of endometrial spiral arterioles and its relationship with bleeding pattern after insertion of gamma-shape copper indomethacin-medicated (gamma CuI) and T-shape copper (TCu 220C) intrauterine devices (IUD). METHODS: Endometrium specimens of late secretory phase were obtained from fertile age women: 10 from preinsertion, 10 obtained after insertion of TCu 220C IUD, and 9 obtained after insertion of gamma CuI IUD. Samples were sectioned serially and morphometric analysis of endometrial spiral arterioles was performed under light microscope. RESULTS: The average cross section area (Area), maximum diameter (Dmax) and minimum diameter (Dmin) of spiral arterioles in both spongeous and dense layers of endometrium increased significantly after insertion of TCu 220C IUD. After insertion of gamma CuI IUD, the Area and Dmax increased in dense layer only, though less obviously than that occurred in TCu 220C group. However, the Dmin increased more obviously in both spongeous and dense layers than after insertion of TCu 220C IUD, implying that the shape of spiral arterioles was more regular in gamma CuI group. CONCLUSION: gamma CuI IUD has less effects on the morphological changes of endometrial spiral arterioles, and this may relate to its indomethacin-contained which causes less bleeding.

Adult↗
PubMed2000

Prostate cryoablation without an insertion kit using direct transperineal placement of ultrathin freezing probes.

A modified technique for prostate cryoablation is described. Prostate cryoablation was performed with a gas-based cryomachine using multiple 17-gauge probes. The 17-gauge probes were inserted via a transperineal route directly into the prostate without using an insertion kit. Probe insertion and positioning are simplified, and operative time is reduced. The perineum is less crowded with devices and tubes. Miniaturizing the cryoprobes and their tubing is feasible. The smaller diameter enables direct insertion without an insertion kit. The surgical result does not seem to be inferior to that of conventional ablation, and penetrating trauma to the prostate is minimal. To the best of our knowledge, this is the first report of transperineal prostate cryoablation performed without an insertion kit.

Cryosurgery↗
PubMed2000

Otolaryngologists' perceptions of the indications for tympanostomy tube insertion in children.

BACKGROUND: Bilateral myringotomy with insertion of tympanostomy tubes is the most common operation that children in Canada undergo. Area variations in surgical rates for this procedure have raised questions about indications used to decide about surgery. The objective of this study was to describe the factors that influence otolaryngologists to recommend tympanostomy tube insertion in children with otitis media and their level of agreement about indications for surgery. METHODS: A survey was sent to all 227 otolaryngologists in Ontario in the fall of 1996. The influence of 17 clinical and social factors on recommendations to insert tympanostomy tubes were assessed. Case vignettes were used to determine the effect of multiple factors in decisions about the need for surgical management. RESULTS: Surveys were returned by 138 (68.3%) of the 202 eligible otolaryngologists. There was agreement (more than 90% of respondents) about 6 indications for surgery: persistent effusion, a lack of improvement after 3 months of antibiotic therapy, a history of persistent effusion for 3 or more months per episode of otitis media, more than 7 episodes of otitis media in 6 months, a bilateral conductive hearing loss of 20 dB or more and a persistently abnormal tympanic membrane. Some respondents were more likely to recommend tube insertion if there were parental concerns about hearing problems or the frequency or severity of episodes of otitis media. Otolaryngologists agreed about the role of tympanostomy tubes in 1 of 4 case vignettes but disagreed about whether adenoidectomy should also be performed in that instance. Most viewed tympanostomy tube insertion as beneficial, with few adverse effects. INTERPRETATION: There is a lack of consensus among practising otolaryngologists in Ontario as to which children with recurrent otitis media or persistent effusion should undergo bilateral myringotomy with tympanostomy tube insertion. These findings suggest the need to revisit clinical guidelines for this procedure.

Attitude of Health Personnel↗
PubMed2000

[Assessment of the comprehension of new rephrasing drug package inserts].

BACKGROUND: The information included in drug package inserts is often difficult for users to understand. The impact of rephrasing inserts on comprehension was assessed. SUBJECTS AND METHOD: A community double-blind clinical trial was undertaken with random allocation of subjects to unmodified or modified inserts, in which presentation and structure had been improved and technical content expressed in plain language. A questionnaire on comprehension of the use of four common drugs was administered to all participants. The following aspects were analyzed: indications, interval of administration, administration in relation to meals, contraindications, storage and what to do in cases of missing a dose or improvement in symptoms. RESULTS: 1,560 participants were included, among whom 770 randomly received the unmodified inserts. The mean proportion of correct answers was 45.7% in the unmodified insert group and 75.5% among those who received the modified version. In all groups of age, study level and employment status, participants with modified texts achieved a higher correct response rate than the unmodified group. An improvement > 73% in the correct response rate was observed in interval of administration, administration in relation to meals and what to do in cases of missing a dose. With the modified leaflet the odds ratio of successfully answering more than 70% of questions was 13.5 (95% confidence interval, 10.5-17.5) compared with the unmodified leaflet. CONCLUSIONS: The comprehension of drug package inserts may be considerably improved by making simple changes in their content. These changes may contribute to accident prevention or inappropriate use of commonly prescribed drugs.

Adolescent↗
PubMed2001

Routine chest X-rays after insertion of implantable long-term venous catheters: necessary or not?

Can long-term subcutaneous venous (Mediport) catheters be safely inserted without routine chest X-ray (CXR) verification? An estimated 500,000 Mediport catheters are inserted yearly in the United States, and elimination of unnecessary radiographs would result in substantial savings of increasingly limited health care resources. A total of 513 consecutive Mediport catheters were inserted by a single surgeon over a 5-year period using a standardized protocol and selective indications for follow-up CXR that included unilateral chest pain, aspiration of air, decreased breath sounds, and difficult catheter insertion. The 513 catheters were inserted in 498 patients with 271 patients (53%) undergoing postprocedure CXR. Of the 513 catheters 461 (90%) were placed by percutaneous approach to the subclavian vein. Six pneumothoraces (1.2% incidence) occurred, all in patients who met criteria for immediate CXR. The overall complication rate was 3.1 per cent and included eight instances of catheter-tip malposition (seven of the eight were successfully repositioned by vascular radiology), one mediastinal hematoma, and one chest-wall hematoma. This largest single-surgeon-reported series demonstrates that Mediport insertion can be safely accomplished with minimal complications following a standardized protocol using selective radiologic evaluation.

Adolescent↗
PubMed2001

The use of low-dose rocuronium to facilitate laryngeal mask airway insertion.

In this two-phase study, the efficacy of low-dose rocuronium to facilitate laryngeal mask airway (LMA) insertion was evaluated. First, the onset time of 100, 150 and 300 micrograms.kg-1 rocuronium was determined using mechanomyography in three groups of patients (n = 10 in each) anaesthetized with propofol-fentanyl-nitrous oxide. In the second part, 100, 150 or 300 micrograms.kg-1 rocuronium or placebo was administered randomly to four groups of patients (n = 50 in each) in a double-blind manner. Following this, anaesthesia was induced with propofol 2.5 mg.kg-1. Patients in the group of 300 micrograms.kg-1 rocuronium or placebo received propofol after 1.5 min. Patients in the group of 100 or 150 micrograms.kg-1 rocuronium received propofol after 3 min. The LMA was inserted 90 sec later. Immediately before the induction of anaesthesia, patients were questioned about the symptoms of neuromuscular block. In phase 1, onset times were 180 sec (SD 41), 191 sec (59) and 89 sec (34), respectively. In phase 2, insertion of the LMA was graded as easy in 90.6% of patients receiving rocuronium, compared with 42% of patients who had only propofol (P < 0.05). Rocuronium improved the overall ease of LMA insertion. LMA insertion was graded easy in 80% of patients who received 100 micrograms.kg-1 rocuronium. The incidence of unpleasant effects was greatest with 300 micrograms.kg-1 rocuronium. The optimal dose needed to facilitate LMA insertion with minimal unpleasant effects appeared to be 100 micrograms.kg-1 rocuronium.

Adult↗