Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “LARYNGOSCOPY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 883 records · Page 49Linked to original sources
PubMed1985

Retrograde intubation in patients undergoing open heart surgery.

Cardiovascular changes during difficult intubation were studied in 25 patients undergoing open heart surgery. The study was divided into two phases. Phase A from the first laryngoscopy to the fourth unsuccessful one; Phase B from a stabilization period until after retrograde intubation was performed. During phase A, heart rate (HR) increased significantly from 75 +/- 6.5 beats/min before laryngoscopy to 95 +/- 8.5 (p less than 0.05) after the last laryngoscopy. Mean arterial pressure (MAP) also increased from 82.5 +/- 4.75 mmHg to 105 +/- 5.15 (p less than 0.005) after the last laryngoscopy. Cardiac index (CI) decreased from 2.9 +/- 0.3 L . min-1 . m-2 before to 2.55 +/-0.2 after the last laryngoscopy. Pulmonary capillary wedge pressure (PCWP) increased from 10.5 +/- 1 mmHg before to 19.25 +/- 1.5 (p less than 0.01) after the last laryngoscopy. No statistically significant changes in HR, MAP, CI, and PCWP occurred before and after intubation during Phase B. Three patients had elevated ST segments during Phase A which responded to IV nitroglycerin and propranolol. None was detected during Phase B. There were more lacerated lips and teeth damaged during Phase A. One patient developed a small peritracheal haematoma after the retrograde intubation, for which no treatment was required. This technique is safe and produces minimal cardiovascular changes for difficult intubation in patients undergoing open heart surgery.

Aortic Valve↗
PubMed2002

Fentanyl is more effective than remifentanil at preventing increases in cerebral blood flow velocity during intubation in children.

PURPOSE: Controlling the cerebral and systemic hemodynamic responses to laryngoscopy and tracheal intubation may play a role in determining clinical outcome in pediatric neurosurgical patients. This study compared the effects of remifentanil and fentanyl on cerebral blood flow velocity (CBFV) and hemodynamic profile during laryngoscopy and tracheal intubation in children under sevoflurane anesthesia. METHODS: Sixty healthy children aged two to six years undergoing dental surgery under general anesthesia were enrolled. Each child was randomly assigned to receive a remifentanil or fentanyl infusion, at a rate of 0.75, 1.0, or 1.5 microg x kg(-1) x min(-1) after induction of anesthesia with 2% sevoflurane. Middle cerebral artery blood flow velocity was measured by transcranial Doppler (TCD) sonography. Once a baseline set of hemodynamic variables and TCD measurements were recorded, the opioid infusion was started. Measurements were taken at two-minute intervals, starting four minutes prior to laryngoscopy until four minutes following naso-tracheal intubation. RESULTS: Remifentanil caused a more significant decrease in mean arterial pressure and CBFV prior to tracheal intubation than did fentanyl (P < 0.001). During laryngoscopy and for two minutes following tracheal intubation, CBFV increased in all remifentanil groups (P < 0.05), whereas it remained stable in all fentanyl groups. CONCLUSION: This study suggests that fentanyl was more effective than remifentanil at preventing increases in CBFV during and immediately following laryngoscopy and tracheal intubation in children undergoing sevoflurane anesthesia. Fentanyl also seemed to provide a more stable hemodynamic profile prior to laryngoscopy and tracheal intubation when compared to remifentanil.

Blood Flow Velocity↗
PubMed2006

The use of the GlideScope for tracheal intubation in patients with ankylosing spondylitis.

BACKGROUND: The GlideScopeVideo Laryngoscope is a new intubating device. The aim of the study was to investigate the use of the GlideScopefor tracheal intubation in patients with ankylosing spondylitis (AS) undergoing general anaesthesia. METHODS: Twenty AS patients were chosen to undergo tracheal intubation by the GlideScope. Preoperative airway assessments were carried out to predict the difficulty of tracheal intubation. Before intubation all patients were given a modified Cormack and Lehane (MCLS) grade and percentage of glottic opening (POGO) score by a separate anaesthetist using a Macintosh size 3 blade. The patients were then intubated, using the GlideScope, by a different anaesthetist during which the larynx was inspected and given another MCLS grade and POGO score. RESULTS: Twelve of the AS patients were judged to have had difficult intubation by preoperative airway assessment. Eleven of the twelve patients had MCLS grades III or IV by direct laryngoscopy and were considered to have had a difficult laryngoscopy. Naso-tracheal intubations by the GlideScope were successful on 17/20 occasions, including 8 of the 11 difficult laryngoscopy. The GlideScope improved the MCLS grade and POGO score in the majority of AS patients compared with direct laryngoscopy (P<0.01). CONCLUSIONS: The GlideScope provides a better laryngoscopic view than that of direct laryngoscopy. Most of the AS patients presenting with MCLS grade III or IV by direct laryngoscopy can be intubated successfully by the GlideScope. In elective patients with AS, awake fibreoptic intubation offers a higher level of security because it can be applied while maintaining spontaneous breathing. The use of GlideScope for tracheal intubation may be an alternative option in these patients who prefer their airway management under anaesthesia.

Adult↗
PubMed1999

The intubating laryngeal mask airway with and without fiberoptic guidance.

UNLABELLED: We conducted this feasibility study using the intubating laryngeal mask airway (ILMA) and a polyvinyl chloride tracheal tube to compare success rates, hemodynamic effects, and postoperative morbidity with two methods of tracheal intubation. After ethics approval and informed consent, 90 healthy ASA physical status I or II women with normal airways were enrolled in the randomized, controlled study. After a standardized inhaled anesthesia induction protocol, tracheal intubations using ILMA with fiberoptic guidance (ILMA-FOB) and ILMA inserted blindly without fiberoptic guidance (ILMA-Blind) were compared with the control group of direct laryngoscopy (laryngoscopy group). All 90 patients were successfully ventilated. For tracheal intubation, success rates were equal in all three groups (97%). Total intubation times were longer for the ILMA-FOB group (77 s versus 48.5 s for laryngoscopy and 53.5 s for ILMA-Blind). The laryngoscopy group had a larger increase in mean arterial blood pressure to tracheal intubation. There were no differences in postoperative sore throat or hoarseness among the groups. In conclusion, success rates are equally high for tracheal intubation using ILMA-Blind and ILMA-FOB techniques in women with normal airways. IMPLICATIONS: The intubating laryngeal mask airway (ILMA) can be used as a primary airway for oxygenation and ventilation. Both methods of tracheal intubation using the ILMA were equally successful. Postoperative morbidity in the ILMA groups was similar to that in the laryngoscopy group. For women with normal airways, both the ILMA inserted blindly and the ILMA with fiberoptic guidance are suitable alternatives to laryngoscopy for tracheal intubation.

Adult↗
PubMedDate not supplied

Color Doppler imaging for vocal cord palsy.

BACKGROUND: Conventional techniques of laryngoscopy for vocal cord palsy can sometimes be difficult or impossible to perform, and B-mode real-time ultrasonography has been previously reported by the authors to be helpful in these situations. In some cases, however, B-mode ultrasonography can be inconclusive. We investigated whether color Doppler imaging can significantly improve vocal cord examination in these cases. METHOD: Ten normal volunteers were examined using the Acuson 128XP/5 with a 7-MHz L7384 linear transducer. The thyroid cartilage was used as an acoustic window. Several distinct color flow patterns were observed with the subjects breathing quietly at rest, at the start of vocalization, and in prolonged phonation. Eight patients with hoarseness of voice were then examined by two separate observers in a double-blinded fashion. The first observer performed B-mode ultrasonography and color Doppler imaging, while the second observer performed indirect laryngoscopy and direct fiberoptic laryngoscopy. RESULTS: Laryngoscopy was used as the standard for comparison. B-mode real-time ultrasonography correctly identified vocal cord palsy in three patients and normal vocal cords in one. The remaining four patients were reported as equivocal or normal. Color Doppler imaging correctly identified the problem in all eight patients. CONCLUSION: Color Doppler imaging for vocal cord examination is more sensitive than B-mode real-time ultrasonography, and seems to be as accurate as laryngoscopy in determining vocal cord palsy or paresis.

Adult↗
PubMed1993

Nifedipine attenuates the hypertensive response to tracheal intubation in pregnancy-induced hypertension.

Thirty women with pregnancy-induced hypertension (PIH) scheduled for Caesarean section under general anaesthesia were studied to evaluate the efficacy of sublingual nifedipine in attenuating the pressor response to laryngoscopy and tracheal intubation. The patients were randomly given either the contents of a nifedipine capsule 10 mg or placebo sublingually 20 min before induction of anaesthesia. Blood pressure and heart rate were recorded at various time intervals. There was a decrease in mean arterial blood pressure (MAP) after pretreatment with nifedipine (P < 0.01). The increase in MAP during laryngoscopy and intubation was higher in the control group compared with nifedipine pretreatment group (P < 0.01). During laryngoscopy and intubation, MAP decreased by 3 mmHg in the nifedipine pretreatment group, while there was an increase of 14 mmHg in the control group. Heart rate increased in both the groups during the laryngoscopy and tracheal intubation (P < 0.01) but the increase was higher in the nifedipine group than in the control group (P < 0.05). Neonatal Apgar scores in both the groups were comparable. These results suggest that sublingual nifedipine is effective in attenuating the hypertensive response to laryngoscopy and intubation but not the tachycardiac response in parturients with PIH.

Administration, Sublingual↗
PubMed1987

Anesthetic induction with fentanyl and intravenous lidocaine for coronary artery surgery.

In a randomized, double-blind trial, 59 patients undergoing coronary artery surgery received fentanyl 10, 15, or 25 microg/kg infused over 5 minutes for anesthetic induction. Half of the patients received intravenous lidocaine, 1.5 mg/kg, 1 minute before laryngoscopy. Efficacy of induction as judged by loss of consciousness was evaluated, and hemodynamic values during induction, laryngoscopy, and tracheal intubation were recorded each minute for 10 minutes. Plasma fentanyl concentrations were determined after termination of the fentanyl infusion. Opioid induction with fentanyl was successful in 90% (18 of 20) of patients receiving 25 microg/kg, 89% (17 of 19) of patients receiving 15 microg/kg, but only 55% (11 of 20) of patients receiving 10 microg/kg (P < .01). While plasma fentanyl concentrations were proportional to the dose infused (25 ng/mL, 18 ng/mL, and 14 ng/mL in the 25, 15. and 10 microg/kg fentanyl groups, respectively), there was no relationship between plasma fentanyl concentration and hemodynamic response to laryngoscopy or intubation. Opioid induction caused a gradual decrease in blood pressure that was restored with intubation. Lidocaine partially blocked this restoration (systolic blood pressure 122 +/- 5 v 138 +/- 5 mmHg, lidocaine v placebo, 1 minute after laryngoscopy, P < .05). Fentanyl, 15 or 25 microg/kg, intravenously, is an effective induction agent for patients with coronary artery disease. Supplementation with intravenous lidocaine, 1.5 mg/kg, will obtund the increase in blood pressure that occurs with laryngoscopy and intubation and help prevent infrequent hypertensive responses seen with this opioid technique.

Adjuvants, Anesthesia↗
PubMed2006

Comparison of direct and video-assisted views of the larynx during routine intubation.

OBJECTIVE: To compare the direct and indirect (video monitor) views of the glottic opening using a new Macintosh blade that is modified to provide a video image of airway structures during laryngoscopy. DESIGN: Prospective multicenter trial. SETTING: 11 university-affiliated hospitals. PATIENTS: 867 adults undergoing elective surgery requiring general anesthesia and tracheal intubation. INTERVENTIONS: Patients received general anesthesia and were paralyzed. Direct laryngoscopy was supervised by one of the investigators at each institution. The best possible view was obtained with a Macintosh video laryngoscope during direct vision using standard techniques such as external laryngeal manipulation and backward, upward, and rightward pressure, if necessary. The laryngoscopist then looked at the video monitor and performed any necessary maneuvers to obtain the best view on the video monitor. Thus, 2 assessments were made during the same laryngoscopy (direct naked-eye view vs video monitor view). Tracheal intubation was then performed using the monitor view. Glottic views were rated according to the Cormack-Lehane scoring system, as modified by Yentis and Lee. A questionnaire was completed for each patient. MEASUREMENTS AND MAIN RESULTS: Data from 865 patients were suitable for analysis. Visualization was considered easy (Cormack-Lehane score<3) in 737 patients and difficult (Cormack-Lehane score=3 or 4) in 21 for both direct and video-assisted views. In 7 patients, the view was considered easy during direct visualization yet difficult on the video monitor view. On the other hand, the view was considered difficult in 100 patients during direct visualization yet easy on the video monitor view (P<0.001). CONCLUSIONS: Video-assisted laryngoscopy provides an improved view of the larynx, as compared with direct visualization. This technique may be useful for cases of difficult intubation and reintubation as well as for teaching laryngoscopy and intubation.

Adult↗
PubMed1999

Lightwand intubation does not reduce the increase in intraocular pressure associated with tracheal intubation.

OBJECTIVE: To evaluate the changes in hemodynamic variables and intraocular pressure (IOP) after tracheal intubation using either lightwand or direct-vision laryngoscopy techniques. DESIGN: Prospective, randomized study. SETTING: Inpatient anesthesia at a University Anesthesia Department. PATIENTS: 50 normotensive, ASA physical status I and II patients, without ocular or cardiovascular diseases, and with a Mallampati score no greater than 2. INTERVENTIONS: After intravenous (i.v.) midazolam premedication (0.05 mg.kg-1), general anesthesia was induced with fentanyl (1 microgram.g-1) and thiopental sodium (5 mg.g-1) followed by vecuronium bromide (0.1 mg.g-1), then patients were randomly allocated to receive either the lightwand (Trachlight, n = 25) or direct-vision laryngoscopy (Laryngoscopy, n = 25) intubating techniques. General anesthesia was maintained with 1% isoflurane and 60% nitrous oxide in oxygen mixture for 5 minutes. MEASUREMENTS AND MAIN RESULTS: Baseline hemodynamic variables were recorded 10 minutes after i.v. premedication, and then every minute after tracheal intubation. Intraocular pressure measurements were performed by means of a computerized indentation tonometer after general anesthesia induction and then 1 and 5 minutes after tracheal intubation. In both groups, mean arterial blood pressure and heart rate increased from baseline, without differences between the two groups. One minute after intubation, IOP increased in both groups: the mean percentage increase was 32% in the Laryngoscopy group and 16% in the Trachlight group. However, this difference was not statistically significant. Five minutes after intubation, IOP decreased to baseline values in both groups. CONCLUSION: We conclude that in healthy patients without ocular disease, using a lightwand intubating technique does not reduce the hemodynamic responses and increase in IOP associated with tracheal intubation as compared with conventional direct-vision laryngoscopy.

Anesthesia, General↗
PubMed2003

A new mirrored laryngoscope.

A new laryngoscope has been designed, incorporating an adjustable mirror and a levered tip similar to the McCoy blade, in an attempt to bridge the gulf between simple direct laryngoscopy and fiberoptic laryngoscopy. Manual in-line neck stabilisation was used to simulate difficult laryngoscopy in 14 anaesthetised patients after full neuromuscular blockade. The best view at laryngoscopy was assessed using a standard Macintosh laryngsocope, a size 3 McCoy laryngoscope and the mirrored laryngoscope. The best laryngeal view obtained in all cases with the Macintosh blade was a grade 3. The mirrored laryngoscope improved this view in 10 cases (71%) compared with five cases (36%) with the McCoy laryngoscope (p = 0.005); in seven cases (50%), the view improved to a grade 1 compared with no cases when the McCoy was used (p = 0.02). We conclude that the mirrored laryngoscope offers considerable advantages over the Macintosh and the McCoy laryngoscopes in simulated difficult laryngoscopy, is simple to use and requires no special training.

Anesthesia, General↗
PubMed2001

Fibreoptic nasal intubation in children with anticipated and unanticipated difficult intubation.

The establishment of a tracheal airway with direct laryngoscopy can be either a very difficult or an impossible task in children with congenital or acquired facial malformations. Out of 46 patients categorized as difficult tracheal intubation, fibreoptic laryngoscopy was used successfully in 44 children anaesthetized by mask with sevoflurane and oxygen or by an intravenous infusion of propofol and mask oxygenation. There were two failures (4.3%). One was due to excessive bleeding and secretions produced by the multiple attempts to intubate with direct laryngoscopy and the other failure in a patient with Pierre Robin syndrome and very small nasal passages that precluded the introduction of the endoscope. Fibreoptic laryngoscopy was successful in 37 cases (80.4%) on the first attempt to intubate and in seven (15.2%) on a second or third attempt. We conclude that fibreoptic laryngoscopy in anaesthetized children with difficult anticipated or unanticipated tracheal intubation in trained hands is a safe technique that can be lifesaving. Therefore, we urge all anaesthesia trainees to become proficient in fibreoptic tracheal intubation.

Adolescent↗
PubMedDate not supplied

A comparison of rapid-sequence intubation and etomidate-only intubation in the prehospital air medical setting.

OBJECTIVES: To compare laryngoscopy conditions produced by etomidate-only intubation (EOI) with those produced by rapid-sequence intubation (RSI) in the prehospital air medical setting. METHODS: A prospective crossover trial design used two helicopters staffed by the same flight paramedics and nurses. Each aircraft used an EOI protocol (0.3 mg/kg) for six months. An RSI protocol using the same dose of etomidate plus succinylcholine (1.5 mg/kg) was used for the alternate six months. Laryngoscopy conditions were graded by three scales: 1) a formal Laryngoscopy Grading Scale (LGS), 2) the Percentage of Glottic Opening (POGO) score, and 3) subjective overall intubation difficulty using a Likert scale of 1 (very easy) to 5 (very difficult). Orotracheal intubation success was also recorded. RESULTS: Forty-nine patients were intubated using the EOI (n = 24) and RSI (n = 25) protocols. Mean age was 38 years, 76% were male, and 90% were intubated for trauma. Fifteen (63%) of the 24 EOI patients required additional etomidate (n = 3) or RSI (n = 12) to allow intubation, while one (4%) of the 25 RSI patients required additional medication dosing (p < 0.0001). Laryngoscopy conditions were assessed for all patients. Good or acceptable conditions as assessed by the LGS were seen in 79% of RSI patients and 13% of EOI patients (p < 0.0001). Mean rates of POGO visualization were 60% with RSI and 12% with EOI (p < 0.0001). Mean global intubation difficulty scores were 3.0 (moderate) with RSI and 4.7 (difficult to very difficult) with EOI (p < 0.0001). Ninety-two percent of the patients undergoing RSI and 25% of the EOI patients were successfully orotracheally intubated (p < 0.0001). CONCLUSIONS: Patients receiving RSI had better laryngoscopy conditions and were easier to intubate than patients receiving EOI. Intubation success rate was higher with RSI.

Adolescent↗
PubMed1996

Effect of neuromuscular block on depth of anaesthesia as measured by the auditory evoked response.

In a double-blind, randomized, controlled, prospective study, we have investigated the effects of vecuronium and laryngoscopy on the auditory evoked response (AER) of the electroencephalogram (EEG) in 40 ASA I and II patients under steady state anaesthesia. After stable anaesthesia had been achieved with 1.0 MAC of isoflurane and nitrous oxide in oxygen, patients were allocated randomly to receive two separate doses of vecuronium 0.05 mg kg-1 or saline. The AER was recorded before and after each dose and then after 20-s laryngoscopy in each group to determine any changes in the early cortical components of the AER waveform (Pa and Nb). There were no statistically significant changes between the vecuronium and saline groups. However, there was a statistically significant increase in mean Pa amplitude of 36% (P = 0.008) and a reduction in mean Nb latency of 6% (P = 0.05) after laryngoscopy in both the paralysed and unparalysed groups, and these changes did not differ significantly between groups. There were correspondingly significant haemodynamic responses to laryngoscopy in both groups. We conclude that neuromuscular block with vecuronium does not affect depth of anaesthesia as measured by the AER in either stimulated or unstimulated patients. In addition, we have demonstrated clearly the arousal effect of laryngoscopy on the AER.

Adult↗
PubMed2001

Sevoflurane EC50 and EC95 values for laryngeal mask insertion and tracheal intubation in children.

The laryngeal mask airway (LMA) is a simple, easy to use and safe method for airway control in children. Its insertion needs less anaesthetic, and haemodynamic responses and postoperative sequelae are less than with laryngoscopy and tracheal intubation. This study was designed to determine the end-tidal concentrations of sevoflurane where 50% (EC50) and 95% (EC95) of the attempts to secure the airway would be successful. We randomly assigned 40 children aged 4-12 yr undergoing general surgery to either LMA insertion (n=20) or to laryngoscopy and tracheal intubation (n=20) under sevoflurane anaesthesia. The initial end-tidal concentration of sevoflurane for each child was determined according to the response of the previous child in the same group. Up to three attempts to secure the airway with increasing sevoflurane end-tidal concentrations in 0.3% steps were allowed for each child. The logistic regression model was used to calculate the EC50 and EC95 values. Sevoflurane provided good conditions for both LMA insertion, and laryngoscopy and tracheal intubation without serious adverse effects. The EC50 and the EC95 of sevoflurane were 1.57 (SD 0.33)% and 2.22% for LMA insertion and 2.20 (SD 0.31)% and 2.62% for laryngoscopy and tracheal intubation. Thus, less sevoflurane is required for LMA insertion in children than for laryngoscopy and tracheal intubation.

Anesthetics, Inhalation↗
PubMed1996

Force and torque vary between laryngoscopists and laryngoscope blades.

Several studies have examined the effects of patient characteristics on force of laryngoscopy, but little attention has been paid to the importance of technique and equipment. This study investigated whether force, torque, head extension, and view varied significantly between laryngoscopists and compared force and torque using Macintosh 3 and Miller 2 blades. The study population consisted of ASA grade I and II patients requiring general anesthesia and endotracheal intubation for elective surgery. Force, torque, head extension, and laryngeal view were highly reproducible when laryngoscopy was repeated by the same individual, Force and torque showed great variation between laryngoscopies performed by different anesthetists, For example, peak force varied over a range of 56 newtons among patients, but could also vary as much as 30 newtons between different anesthetists repeating laryngoscopy in the same patient. Force and head extension were 30% less with Miller laryngoscope compared to the Macintosh. Thus, laryngoscopic force and torque depend on technique and equipment. Further studies of force and torque may lead to improved techniques. The force-measuring laryngoscope could be a useful tool in teaching laryngoscopy.

Adult↗
PubMed2001

A videographic analysis of laryngeal exposure comparing the articulating laryngoscope and external laryngeal manipulation.

Activation of the articulating laryngoscope and external laryngeal manipulation (ELM) improve laryngeal exposure during direct laryngoscopy. We used a head-mounted direct laryngoscopy imaging system and a previously validated scoring system for assessing laryngeal view (the percentage of glottic opening or POGO score) on 33 adult patients undergoing laryngoscopy. On each patient, we videotaped the initial laryngeal exposure (blade not activated), the view with activation of the blade, and the view with operator-directed external laryngeal manipulation. The video recordings were reviewed and the laryngeal view assessed with POGO scores. POGO scores improved with blade activation in 9/33 (27%) of patients vs 28/33 (85%) of patients with ELM. In nearly half of patients studied (16/33, 48%) POGO scores decreased with blade activation. We conclude that ELM is superior to articulating laryngoscope blade activation in improving POGO scores during laryngoscopy on adult patients in standard sniffing position. Using recordings from a direct laryngoscopy video system, we compared laryngeal views in 33 patients with a special articulating laryngoscope blade to views achieved by external laryngeal manipulation (pressing on the patient's neck). Laryngeal exposure, which is important for placement of tracheal tubes, was better with external laryngeal manipulation.

Adult↗
PubMed1999

Clinical assessment of a plastic optical fiber stylet for human tracheal intubation.

BACKGROUND: The authors compared the performance of a prototype intubation aid that incorporated plastic illumination and image guides into a stylet with fiberoptic bronchoscopy and direct laryngoscopy for tracheal intubation by novice users. METHODS: In a randomized, nonblinded design, patients were assigned to direct laryngoscopy, fiberoptic bronchoscopy, or imaging stylet intubation groups. The quality of laryngeal view and ease with which it was attained for each intubation was graded by the laryngoscopist. Time to intubation was measured in 1-min increments. A sore-throat severity grade was obtained after operation. RESULTS: There were no differences in demographic, physical examination, or surgical course characteristics among the groups. The laryngoscope produced an adequate laryngeal view more easily than did the imaging stylet or bronchoscope (P = 0.001) but caused the highest incidence of postoperative sore throat (P<0.05). Although the time to intubation for direct laryngoscopy was shorter than for imaging stylet, which was shorter than fiberoptic bronchoscopy (P<0.05), the quality of laryngeal view with the imaging stylet was inferior to both direct laryngoscopy and fiberoptic bronchoscopy techniques (P<0.05). CONCLUSIONS: Novices using the imaging stylet produce fewer cases of sore throat (compared with direct laryngoscopy) and can intubate faster than when using a bronchoscope in anesthetized adult patients. The imaging stylet may be a useful aid for tracheal intubation, especially for those unable to maintain skills with a bronchoscope.

Adult↗
PubMed2001

Randomized study comparing the "sniffing position" with simple head extension for laryngoscopic view in elective surgery patients.

BACKGROUND: The "sniffing position" is recommended for optimization of glottic visualization under direct laryngoscopy. However, no study to date has confirmed its superiority over simple head extension. In a prospective, randomized study, the authors compared the sniffing position with simple head extension in orotracheal intubation. METHODS: The study included 456 consecutive patients. The sniffing position was obtained by placement of a 7-cm cushion under the head of the patient. The extension position was obtained by simple head extension. The anesthetic procedure included two Laryngoscopies without paralysis: the first was used for topical glottic anesthesia. During the second direct laryngoscopy, intubation of the trachea was performed. The head position was randomized as follows: group A was in the sniffing position during the first Laryngoscopy and the extension position during the second, group B was in the extension position during the first laryngoscopy and the sniffing position during the second. Glottic exposure was assessed by the Cormack scale. RESULTS: The sniffing position improved glottic exposure (decreased the Cormack grade) in 18% of patients and worsened it (increased the Cormack grade) in 11% of patients, in comparison with simple extension. The Cormack grade distribution was not significantly modified between the two groups. Multivariate analysis showed that reduced neck mobility and obesity were independently related to improvement in laryngoscopic view with application of the sniffing position. CONCLUSIONS: Routine use of the sniffing position appears to provide no significant advantage over simple head extension for tracheal intubation in this setting. The sniffing position appears to be advantageous in obese and head extension-limited patients.

Adult↗