OSCEs in Japanese postgraduate clinical training Hiroshima experience 2000-2009

BACKGROUND

Hiroshima University Hospital used the Objective Structured Clinical Examination (OSCE) as a formative and summative assessment tool to evaluate trainees' competence.

AIM

To reflect on Hiroshima University Hospital experience of OSCEs in postgraduate training in terms of OSCE structure and trainees' perception of the OSCE they attended.

METHODS

A total 27 OSCEs implemented in Hiroshima University Hospital from 2000 to 2009 were examined. The OSCE in postgraduate training, Hiroshima University Hospital, was influenced by many factors from organisational and pedagogical perspectives, and changed to meet social and curriculum needs. At each OSCE, all examinees were required to answer an anonymous questionnaire, which consisted of ten checklists, just after their experience of OSCE.

RESULTS

Five hundred and forty trainees who attended each OSCE were required to answer a questionnaire and 510 were returned (94.4%). In the comparison between formative and summative OSCEs, the number of trainees who answered "the OSCE is meaningful" in formative OSCE was significantly higher than that in summative OSCE (P < 0.001). In the comparison between before and after the 2006/2007 academic year, trainees who indicated that OSCEs were meaningful increased after 2006/2007 (P < 0.05), and trainees who felt they were evaluated appropriately by these OSCEs increased after 2006/2007 (P < 0.01).

CONCLUSION

Trainees viewed OSCEs positively and appreciated their effectiveness from a pedagogical perspective, and OSCE positively affected the trainees' approach to learning. A ten-year process of OSCE change has helped with educational reforms because of its adaptability. Flexible attitudes to change are necessary for stakeholders to achieve the desired reforms.

Influence of socio-economic background and antenatal care programmes on maternal mortality in Surabaya, Indonesia

OBJECTIVE

To determine the risk factors, such as socio-economic background, quality of antenatal care and availability of family planning, responsible for high maternal mortality in Surabaya, Indonesia.

METHODS

The study used a case-control design. Descriptive, bivariate and multivariate analyses were carried out, comparing 59 maternal deaths and 177 women survivors in the referral hospital, from 1996 to 1999.

RESULTS

The risk factors for maternal mortality were: living outside of Surabaya [odds ratio (OR) = 11.7, 95% confidence interval (CI) = 5.0-29.2], unemployment (OR = 4.4, 95% CI = 1.7-13.8), unavailability of toilet facilities (OR = 2.9, 95% CI = 1.0-7.7), <4 antenatal visits (OR = 2.5, 95% CI = 1.1-5.5) and initial visit to antenatal care facilities after the fourth month of pregnancy (OR = 3.0, 95% CI = 1.3-7.0). There was no significant association between maternal mortality and the availability of family planning.

CONCLUSION

Low socio-economic background and the availability of antenatal care have a significant influence on maternal mortality in Surabaya, Indonesia.

Hemodynamic responses among three tracheal intubation devices in normotensive and hypertensive patients

We compare hemodynamic responses in normotensive and hypertensive anesthetized paralyzed patients among three intubation devices: the Macintosh laryngoscope (LS), the Trachlight lightwand (LW), and the intubating laryngeal mask airway Fastrach (ILM). Seventy-five normotensive and 75 hypertensive patients were randomly assigned to each intubation device (n = 25). Noninvasive systolic blood pressure (SBP) and diastolic blood pressure (DBP) and heart rate (HR) were recorded immediately preinduction, immediately preintubation, and every minute for the first 5 min after the successful intubation. The number of intubation attempts, the time to successful intubation, and any airway injuries were recorded. Pharyngolaryngeal morbidity was assessed 18-24 h after surgery by a blinded investigator. In all groups, there was a reduction in SBP and DBP but no change in HR immediately preintubation compared with baseline values. In all groups, HR increased, but there were no increases in SBP and DBP other than in DBP in the LS/hypertensive group after intubation compared with baseline values. In normotensive patients, there were no differences in any hemodynamic variables among the three devices. In hypertensive patients, SBP and DBP in the LS group were significantly higher than the ILM and LW groups for 2 min after intubation, but there were no differences in HR among the devices. The number of intubation attempts was similar among groups, but intubation time was longer for the ILM group. The incidence of airway injury was more frequent for the ILM than the LS and LW groups (16% versus 0% versus 0%). There were no differences in pharyngolaryngeal morbidity among groups. We conclude that both the ILM and the LW attenuated the hemodynamic stress response to tracheal intubation compared with the LS in hypertensive, but not in normotensive, anesthetized paralyzed patients.

IMPLICATIONS

Both the intubating laryngeal mask airway Fastrach and the Trachlight lightwand attenuate the hemodynamic stress response to tracheal intubation compared with the Macintosh laryngoscope in hypertensive, but not in normotensive, anesthetized paralyzed patients.

Human GLUT5 immunolabeling is useful for evaluating microglial status in neuropathological study using paraffin sections

In neuropathological studies it is important to detect both resting and reactive microglia in paraffin sections. We examined the usefulness of human (h) GLUT5, a glucose transporter, as a microglial marker. We produced an hGLUT5 antibody against its C-terminal sequence and stained human brain tissue sections. The hGLUT5 antibody consistently stained microglia in cryostat sections. In paraffin sections fixed with formalin, paraformaldehyde or ethanol, both resting and reactive microglia were stained; the latter were stained more intensely than the former. The hGLUT5 and glial fibrillary acidic protein labeling did not overlap each other in double immunofluorescence analyses. Oligodendrocytes, perivascular cells, choroid plexus epithelium and ependymal cell were negative for hGLUT5. Even after 1-month fixation in formalin, the hGLUT5 antibody stained microglia well. Microwave pretreatment enhanced the immunoreactivity of hGLUT5. As compared with other microglial markers, KP-1, KiM1p, CR3.43 and RCA-1, the hGLUT5 antibody could be considered good morphological marker. hGLUT5 immunolabeling clearly showed the detailed microglial processes, whereas immunolabeling with Ki-M1P and KP-1 showed cytoplasmic granules, and it was difficult to trace the microglial processes. The hGLUT5 antibody stained both resting and reactive microglia, whereas CR3.43 stained only reactive microglia, and RCA-1 labeled microvessels more intensely than microglia. Thus, hGLUT5 is a marker that is suitable for routine histopathological staining procedures.

Intubating laryngeal mask airway size selection: a randomized triple crossover study in paralyzed, anesthetized male and female adult patients

We determined the optimal size of intubating laryngeal mask airway (ILM) for ventilation and blind tracheal intubation in men and women. We also determined the distance the tracheal tube needs to protrude beyond the distal aperture to ensure that the cuff is through the vocal cords. Fifty male and 50 female anesthetized, paralyzed patients (ASA physical status I or II, aged 18-80 yr) were studied. Three operators (A, B, and C) were involved for the purposes of blinding. The size 3, 4, or 5 ILM was inserted into each patient in random order by Operator A, and the quality of ventilation was scored (adequate, suboptimal, or failed) by Operator B. The fiberoptic position (correct, too shallow, or too deep) and the distance between the distal aperture and the vocal cords was determined by Operator B. A single attempt at blind intubation was made by Operator C. Operators B and C were blinded to the size of the ILM. Operator C was also blinded to the information recorded by Operator B. All ILMs were inserted into the laryngopharynx at the first attempt. For men and women, the ventilation score was smaller for the Size 3 than the Size 4 or 5 (all: P < 0.002). For men, correct positioning was less common with the Size 3 than the Size 4 or 5 (both: P < 0.02). For women, correct positioning was similar among sizes. For men, tracheal intubation was successful less frequently with the Size 3 (84%) than the Size 4 (100%) or 5 (98%) (both: P < or = 0.01). For women, tracheal intubation success was similar among sizes (Size 3, 4, and 5: 86%, 96%, and 92%, respectively). Intubation was always successful if the ILM was correctly positioned and always failed if it was too shallow or deep. In both male and female patients, the distance between the distal aperture and the vocal cords increased with increasing ILM size (all: P < 0.04) and patient height (P < 0.0001) and was always longer for men (all: P < 0.0001). The overall mean distance (95% confidence interval) that the tracheal tube needed to protrude was 10-12 cm (8-13 cm) in men and 8-11 cm (8-12 cm) in women. We conclude that for men, the Size 4 and 5 ILMs are better than the Size 3 for ventilation and blind intubation. For women, the Size 4 and 5 ILMs are better than the Size 3 for ventilation, but there is no difference among sizes for blind intubation. The length the tracheal tube must protrude from the distal aperture to ensure that the cuff is completely through the vocal cords is 8-13 cm, depending on ILM size, the tracheal tube size, and the sex and height of the patient.

IMPLICATIONS

For men, the Size 4 and 5 intubating laryngeal mask airways are better than the Size 3 for ventilation and blind tracheal intubation. For women, the Size 4 and 5 are better than the Size 3 for ventilation, but there is no difference among sizes for blind intubation. The length the tracheal tube must protrude from the distal aperture of the intubating laryngeal mask airway to ensure that the cuff is completely through the vocal cords is 8-13 cm, depending on the size of the mask and tracheal tube and on the sex and height of the patient.

Dynamic viscoelasticity of soft liners and masticatory function

Soft denture liners are used for edentulous patients to cushion functional forces. We hypothesized that the application of soft liners having viscoelastic properties would lead to the most marked improvement in masticatory function. The shear storage modulus (G'), shear loss modulus (G''), and loss tangent (tan delta) were determined for 6 materials by means of a dynamic viscoelastometer. Masticatory function of ten subjects was evaluated by measurements of maximum bite forces and chewing times and frequencies for 2 food samples, and by the use of visual analogue scales. The acrylic materials exhibited viscoelastic behavior, while the silicones exhibited elastic behavior. The improvement in masticatory function compared with hard resin was found to be in the order: acrylic permanent materials > silicone > acrylic temporary materials. The results suggest that the use of materials with higher tan delta and G' provides the most optimum masticatory function for patients requiring the provision of soft liners on their dentures.

Effect of viscoelastic properties of resilient denture liners on pressures under dentures

In order to evaluate the influence of viscoelastic properties of resilient denture liners on the pressures under dentures, a series of creep and stress relaxation tests were carried out using a simplified mandibular edentulous model and denture model. Two diaphragm pressure sensors were attached to the edentulous model so that they contacted the residual ridge and the buccal slope. The results may be summarized as follows: (i) The use of resilient denture liners is effective for stress relief under dentures. (ii) The thickness increase of each denture liners causes the effect of stress relaxation. (iii) The material exhibited viscoelastic behaviour after applying the stress and has the ability to distribute stress or stress relaxation. It is important to understand the viscoelastic behaviours of each resilient denture liner and choose the material according to the clinical situation. The information obtained should be useful to clinicians when they select materials for their patients.

Effect of triacylglycerols containing medium- and long-chain fatty acids on body fat accumulation in rats

Effect of triacylglycerols containing medium- and long-chain fatty acids (TML) on body fat accumulation was studied in rats. Male Wistar rats were fed an experimental diet containing 25% soybean oil or TML for 6 weeks. The food intake for 6 weeks did not significantly differ between the two diet groups. However, the perirenal and mesenteric adipose tissue weight and carcass fat content were significantly lower in the TML diet group than in the soybean oil diet group. The epididymal adipose tissue weight and liver triacylglycerol content did not significantly differ between the two diet groups. The digestibility of dietary fat did not significantly differ between the two diet groups. These results suggest that an intake of TML decreases body fat accumulation compared to an intake of soybean oil in rats.

Routine use of the intubating laryngeal mask airway results in increased upper airway morbidity

PURPOSE

The classic laryngeal mask airway (LMA) has a soft, silicone tube and the intubating laryngeal mask airway (ILM) has a rigid, silicone-coated steel tube. We compare postoperative pharyngolaryngeal morbidity in patients randomised to receive either device.

METHODS

Sixty-five female patients (ASA physical status class I or II, aged 18-80 yr) undergoing balanced regional anesthesia for gynecological laparotomy expected to last one to two hours were randomly assigned for airway management with the LMA or ILM. Intracuff pressure was maintained at 60 cm H20. Postoperative pharyngolaryngeal morbidity (sore throat, difficulty swallowing, sore mouth, sore neck/jaw, hoarseness) was assessed at two, 24 and 48 hr by blinded investigators.

RESULTS

The number of insertion attempts and duration of anesthesia was similar between groups. Sore throat was more common for the ILM at two hours (44 vs 15%, P=0.01), 24 hr (59 vs 21%, P=0.008) and 48 hr (34 vs 3%, P=0.005). Sore mouth was more common for the ILM at two hours (16 vs 0%, P=0.02) and 24 hr (12 vs 0%, P=0.04), but not at 48 hr (6 vs 3%). Difficulty swallowing was more common for the ILM at two hours (25 vs 0%, P=0.04), but not at 24 hr (31 vs 3%) and 48 hr (12 vs 9%). There were no differences in the incidence of sore jaw/neck (ILM, 3-12%; LMA, 0-3%) and hoarseness (ILM, 12-31%; LMA, 16-18%). There was no correlation between postoperative pharyngolaryngeal morbidity and duration of anesthesia.

CONCLUSION

Pharyngolaryngeal morbidity is more common with the ILM than the LMA following anesthesia lasting one to two hours.

Increased expression of mXBP-1 (TREB-5) in thymic B cells in New Zealand mice

New Zealand Black mice as well as several other murine models of murine lupus are well known for premature degeneration of thymus and development of autoimmunity. To focus on molecular events unique to murine lupus, we performed differential display using arbitrary primer pairs to distinguish NZB versus BALB/c thymus at 5 weeks of age. Following an extensive analysis of DNA bands that were either consistently up or downregulated and from studies of expression pattern of thymic genes by in situ nucleic acid hybridization, we focused on one clone that was consistently differentially expressed between NZB and BALB/c thymus. This clone was isolated, sequenced, and identified as the murine homologue of the human X box binding protein (hXBP-1), also known as TREB 5. mXBP-1 was found to be consistently upregulated in B cells in the thymic cortex of NZB and (NZBxNZW)F1, but not BALB/c, C3H/HeJ or C57BL/6 mice. In addition, it was dramatically elevated in MRL/ lpr but not MRL/++ mice; similarly, it was increased in BXSB/ Yaa male but not BXSB female thymic cortex. Of particular interest was an absence of mXBP-1 expression in the thymus of NZB/ Bln- Igh6(null)homozygotes. mXBP-1 has several putative functions, including the regulation of MHC class II expression and by virtue of its ability to recognize CRE-like elements shown to be involved in HTLV-1 transcription.

B cells are selectively associated with thymic cortical but not medullary pathology in NZB mice

Abnormal expansion of autoantibody-synthesizing B cells and self-reactive T cells, which most likely escape negative selection within the thymus, have both been characterized and reasoned to play a role in the pathogenesis of autoimmunity in NZB mice. Support for this thesis has been our observation that NZB mice have severe cortical and medullary thymic microarchitectural defects. As a means to dissect the roles of T and B cells in the induction of such abnormalities, B cell-deficient NZB mice were bred by backcrossing the Igh6(null)allele on to the NZB background (NZB-muMT mice). Such mice showed undetectable levels of autoantibodies. NZB-muMT mice, as compared to wild-type NZB mice, had lower absolute numbers of CD4(+)T cells. Furthermore, thymic abnormalities in NZB-muMT mice were restricted to the medulla. These data suggest that, while B cells may play a role in thymic cortical abnormalities, the medullary abnormalities are induced by other mechanisms.

The thermic effect is greater for structured medium- and long-chain triacylglycerols versus long-chain triacylglycerols in healthy young women

The purpose of this study was to investigate the hypothesis that a single dose of structured medium- and long-chain triacylglycerols (SMLCTs) composed of medium-chain (20%) and long-chain (80%) fatty acids would increase the metabolic rate more than a dose of long-chain triacylglycerols (LCTs) in 15 healthy young women aged 18 to 28 years. The effects on postingestive energy expenditure were compared for SMLCTs versus LCTs. On the experimental days, the subjects fasted overnight and then ingested 1,680 kJ SMLCTs or LCTs each day. Energy expenditure and the respiratory quotient (RQ) were measured before and after SMLCT and LCT ingestion by indirect calorimetry. Blood samples were collected before and after ingestion to obtain plasma and serum. Postingestive total energy expenditure (PTEE) was significantly higher after SMLCT ingestion versus LCT ingestion (26.9 +/- 1.0 v 25.5 +/- 1.1 kJ/kg/6 h, P < .05). The thermic effects of the test oil were also significantly greater after SMLCT ingestion compared with LCT ingestion (3.02 +/- 0.49 v 1.47 +/- 0.82 kJ/kg/6 h, P < .01). Plasma glucose and serum triacylglycerol concentrations were not significantly different. Serum free fatty acid and 3-hydroxybutyric acid concentrations were higher after SMLCT ingestion versus LCT ingestion. These results suggest that long-term substitution of SMLCTs for LCTs will produce body fat loss if energy intake remains constant.

Airway rescue with the intubating laryngeal mask in a patient with an unexpectedly large epiglottic cyst

We report the successful use of the intubating laryngeal mask airway for rescue and intubation in an anaesthetised patient with an unexpectedly large epiglottic cyst. This case illustrates that airway rescue and intubation with the intubating laryngeal mask is possible and preoperative airway assessment does not always provide reliable information about airway management.

Haemodynamic responses to the intubating laryngeal mask and timing of removal

We determined (a) the haemodynamic responses to intubating laryngeal mask (ILM) airway insertion/intubation and removal in anaesthetized patients, and (b) whether the timing of ILM removal influences these responses. One-hundred and twenty patients without cardiovascular disease were studied. ILM airway insertion/intubation was 5 min after induction with propofol 2 mg kg(-1) and maintenance of anaesthesia with sevoflurane 2% in oxygen 33% and nitrous oxide. Patients were randomly assigned for removal of the intubating laryngeal mask airway at 1, 3 and 5 min after successful intubation. Systolic and diastolic arterial pressures and heart rate were recorded preinduction (baseline), before ILM airway insertion/intubation, at 1-min intervals after insertion/intubation, and at 1-min intervals for 5 min after ILM removal. ILM insertion was successful at the first attempt in all patients, but 46 patients required more than one intubation attempt. Compared with baseline values, there were no increases in systolic or diastolic arterial pressure, but there was an increase in heart rate 1 min after ILM insertion/intubation (9%, P<0.001) and 1 min after ILM removal (8%, P<0.01). There was a significant increase in systolic and diastolic pressures and heart rate 1 min after ILM insertion/intubation (30%, 31% and 15%; all: P<0.002) compared with before ILM insertion/intubation values and 1 min after ILM removal (9%, 8% and 7%; all P<0.05) compared with 1 min after ILM insertion/intubation values. Removal of the ILM 1 min after successful intubation resulted in higher arterial pressure compared with removal at 3 min (systolic arterial pressure 10% higher for 1 min, P = 0.01) and 5 min (systolic arterial pressure 10-23% higher for 3 min, P<0.01; diastolic arterial pressure 10-20% higher for 4 min, P>0.02), but there were no differences in heart rate between groups. Systolic and diastolic arterial pressures were greater if more than one intubation attempt was required. Early removal or multiple intubation attempts did not exceed baseline haemodynamic values. We conclude that ILM insertion/intubation and removal in anaesthetized patients produces little or no haemodynamic response, even if multiple intubation attempts are required. The timing of removal exerts a small, but clinically unimportant influence on these responses.

Tissue inhibitor of metalloproteinases-1, matrix metalloproteinases-1 and -8, and collagenase activity levels in peri-implant crevicular fluid after implantation

The integrity of connective tissues surrounding dental implants may be influenced by a balance between matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). The purpose of this study was to provide an overall assessment of TIMP-1, MMP-1 and -8 levels as well as collagenase activities during the wound healing process after implantation and in peri-implantitis lesions. Peri-implant crevicular fluid (PICF) was sampled with sterile paper strips from 10 osseointegrated implants of 6 subjects. Ten implants from 6 patients affected with peri-implantitis were also assessed. Gingival crevicular fluid (GCF) from 11 periodontitis-affected patients and 10 healthy volunteers served as controls. TIMP-1 and MMP-1 and -8 protein levels in the PICF were measured by ELISA, and active and APMA-activatable collagenase activities were determined by functional assays using image-analysis after SDS-PAGE. The experiment showed a significant increase in the TIMP-1 level at 1 week after implantation as compared with that in GCF from healthy periodontium. Four weeks after implantation it had reached the same level as that in the GCF of healthy subjects. The data has also disclosed a higher post-implantation collagenase activity level at 1 week than at weeks 2, 4, and 12. This may be due to the increase in MMP-1 and -8. Furthermore, peri-implantitis and periodontitis were shown to be similar inflammatory lesions in respect to MMP-1 and -8 and collagenase activities, even though the TIMP-1/MMP-1 + MMP-8 ratio was significantly lower in peri-implantitis than in periodontitis. In conclusion, the overproduction of TIMP-1 in the wound area after implantation could, to some extent, inhibit excessive tissue destruction and degradation of the neo-matrix in wound repair due to MMPs.

Determination of sugar alcohols in confectioneries by high-performance liquid chromatography after nitrobenzoylation

A method was developed for the determination of sugar alcohols, meso-erythritol, xylitol, D-glucitol, D-mannitol, maltitol and parachinit by high-performance liquid chromatography (HPLC). The sugar alcohols were converted into strong ultraviolet (UV)-absorbing derivatives with p-nitrobenzoyl chloride. HPLC was performed on a phenyl column, using acetonitrile-water (67:33) as mobile phase and UV detection (260 nm). The calibration curves for all sugar alcohols tested were linear in the 10-250 microg/ml range. The average recoveries of the sugar alcohols from four sugarless confectioneries spiked at 5 and 10% levels of six sugar alcohol standards ranged from 73.2 to 109.0% with relative standard deviations ranging from 0.7 to 9.0%. The detection limit of the developed method was 0.1% for the above sugar alcohols contained in the samples.

Long-term changes of hydroxyapatite-coated dental implants

There are many controversies about the long-term prognosis of hydroxyapatite (HA)-coated implants. Failure may be related to compositional and structural changes of the coating occurring during implantation. Two retrieved and two unused HA-coated blade-type implants were examined by stereomicroscopy, secondary electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and electron probe microanalysis. The objective was to investigate the HA morphology, composition, and structure, and to characterize the changes that occurred in the retrieved implant coatings. Retrieved implants presented partial loss of the coating, especially at the apical and mesiodistal edges. Remaining HA was thick and flattened in the cervical and central areas and gradually thinner and rougher towards the apical and mesiodistal edges. Increase of Cl and Mg, decrease of OH, and X-ray diffraction peak broadening were found in the retrieved implant coatings, in comparison with the unused implants. Morphological changes of the retrieved implants seem to depend on stress values in the surrounding bone and on implant mobility. Compositional changes and increased amount of lattice imperfections appeared in the retrieved implant coatings, as a result of ion substitutions in the apatite lattice. However, the present study could not confirm the influence of these changes on implant failure.

Dynamic viscoelastic properties and the age changes of long-term soft denture liners

The dynamic viscoelastic properties of long-term soft denture liners were measured over a wide range of frequencies using a dynamic viscoelastometer based on a non-resonance-forced vibration principle. Changes in properties over a 3 yr period have also been monitored. One acrylic material, one fluoroelastomer, one heat cured silicone and one self-curing addition silicone were used. Complex dynamic tensile modulus (E*), tensile storage modulus (E'), tensile loss modulus (E") and loss tangent (tan delta) were determined over the frequency range from 0.01 to 100 Hz on administration of a 0.27% strain at 37 degrees C. The dynamic viscoelasticity of the acrylic and fluoroelastomer products was more sensitive to changes in frequency than that of silicone products. The acrylic material and fluoroelastomer exhibited viscoelastic behaviour whilst silicones exhibited elastic behaviour. The silicone products remained unchanged after soaking for 3 yr whilst the acrylic and fluoroelastomer products underwent significant change.

Segmental cervical spine movement with the intubating laryngeal mask during manual in-line stabilization in patients with cervical pathology undergoing cervical spine surgery

We quantified the extent and distribution of segmental cervical movement produced by the intubating laryngeal mask (ILM) during manual in-line stabilization in 20 anesthetized patients with cervical pathology undergoing cervical spine surgery. All patients had neurological symptoms preoperatively. The ILM was inserted with the head and neck in the neutral position. Intubation was facilitated by transillumination of the neck with a lightwand. Cervical movement was recorded with single-frame lateral radiographic images taken 1) immediately before induction (baseline); 2) during ILM insertion (insertion); 3) when transillumination was first seen at the cricothyroid membrane (intubation A); 4) when the tube was being advanced into the trachea (intubation B); and 5) during ILM removal (removal). Radiographic images were digitized and the degree of flexion/extension and posterior movement measured for the occiput (C0) through to C5. During ILM insertion, C0-5 were flexed by an average of 1-1.6 degrees (all P < 0.05). During intubation A/B, C0-4 were flexed by an average of 1.4-3.0 degrees (all P < 0.01), but C5 was unchanged. During ILM removal, C0-3 were flexed by an average of 1 degree (all: P < 0.05), but C3-5 were unchanged. During insertion and intubation A/B, C2-5 were displaced posteriorly by an average of 0.5-1.0 mm (all: P < 0.05). During removal, there was no change at C1-5. Neurological symptoms improved in all patients. We conclude that the ILM produces segmental movement of the cervical spine despite manual in-line stabilization in patients with cervical spine pathology undergoing cervical spine surgery. This motion is in the opposite direction to direct laryngoscopy, suggesting that different approaches to airway management may be more appropriate depending on the nature of the cervical instability.

IMPLICATIONS

The intubating laryngeal mask produces segmental movement of the cervical spine, despite manual in-line stabilization in patients with cervical spine pathology undergoing cervical spine surgery. This motion is in the opposite direction to direct laryngoscopy, suggesting that different approaches to airway management may be more appropriate depending on the nature of the cervical instability.