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Indirect laryngoscopy is one of the procedural methods used for achieving a histopathologic diagnosis of cancer of the larynx. A chronologic historical summary of the development of mirror laryngoscopy is presented. The details of the procedure employed for obtaining a biopsy with the aid of topical anesthesia is discussed.
BACKGROUND: Dexmedetomidine reduces the dose requirements for opioids and anaesthetic agents. The purpose of this study was to evaluate the effect of a single pre-induction intravenous dose of dexmedetomidine 1 microg/kg on cardiovascular response resulting from laryngoscopy and endotracheal intubation, need for anaesthetic agent and perioperative haemodynamic stability. METHODS: Fifty patients scheduled for elective minor surgery were randomised into two groups (dexmedetomidine group and placebo group, n = 25 in each group). During and after drug administration, the Ramsey sedation scale was applied every 5 minutes. Fentanyl 1 microg/kg was administered to all patients and thiopental was given until lash reflex disappeared. Anaesthesia continuation was maintained with 50% : 50%, oxygen : nitrous oxide. Sevoflurane concentration was adjusted to maintain systolic blood pressure within 20% of preoperative values. After extubation, the Steward awakening score was applied at 5 and 10 minutes. Haemodynamic parameters and adverse effects were recorded every 10 minutes for 1 hour after surgery. RESULTS: During intubation the need for thiopental and sevoflurane concentration were decreased by 39% and 92%, respectively, in the dexmedetomidine group compared with the placebo group. In all groups, blood pressure and heart rate increased after tracheal intubation; both were significantly lower in the dexmedetomidine group than in the placebo group (p < 0.05). Fentanyl requirement during the operation was 74.20 +/- 10.53microg in the dexmedetomidine group and 84.00 +/- 27.04microg in the placebo group (p < 0.05). At 5 minutes, the Steward scores were >6 in 56% of the dexmedetomidine group and in 4% of the placebo group (p < 0.05). At 10 minutes, sedation scores were > or =4 in all patients in the dexmedetomidine group (p < 0.05). Arterial blood pressure and heart rate in the postoperative period were significantly lower in the dexmedetomidine group compared with the placebo group (p < 0.05). CONCLUSION: Preoperative administration of a single dose of dexmedetomidine resulted in progressive increases in sedation, blunted the haemodynamic responses during laryngoscopy, and reduced opioid and anaesthetic requirements. Furthermore, dexmedetomidine decreased blood pressure and heart rate as well as the recovery time after the operation.
OBJECTIVE: To evaluate target-controlled infusion (TCI) of remifentail-propofol and the balanced anesthesia of fentanyl-isoflurane during the operation with suspension laryngscope. METHODS: Sixty ASA I-II patients scheduled for the surgery through suspension laryngoscopy were randomly divided into two groups: TCI group and control group. In TCI group, anesthesia was maintained with TCI remifentanil-propofol which was stopped at the end of operation. The target plasma concentration of remifentanil was set at 6 microg/L and propofol at 3 mg/L. In control group, anesthesia was induced with intravenous fentanl 2.5 microg/kg and propofol 1-2 mg/kg, maintained with fentanl 0.03 microg.kg(-1). min(-1) and 1% isoflurane which was stopped at the end of surgery. Intubation was facilitated with succinylcholine 1-1.5 mg/kg.MAP, HR, ECG, S(p)O(2) and P(ET)CO(2) were monitored during anesthesia. The following parameters were recorded and compared between two groups: (1) the changes in blood pressure (BP), heart rate(HR) and S(p)O(2) at different time point; (2) recovery profile including the time of response to verbal commands, autonomous breathing, tracheal extubation, orientation recovery, discharging from PACU after operation; (3) OAAS scores after operation; (4) postoperative complications; (5) unexpected events and awareness during operation. RESULT: (1) The hemodynamics were stable while the target plasma concentration of remifentanil was set at 6 microg/L and propofol at 3 mg/L. (2) During tracheal intubation, suspension laryngoscope was inserted, and extubation MAP was significantly lower in TCI group than that in control group; (3) There were no significant differences in hemodynamic values and S(p)O(2) of different time points between two groups. Study group was faster than control group on recovery profile including the time of response to verbal commands, autonomous breathing, tracheal extubation, orientation recovery and discharging from PACU. There was respectively one unexpected event in both groups. CONCLUSION: Remifentanil supplemented with isoflurane anesthesia can achieve the optimal hemodynamic stability during the operation with suspension laryngoscopy and better recovery profile from anesthesia than fentanyl.
We studied nociception-associated arousal following laryngoscopy and intubation in patients scheduled for elective open heart surgery, using EEG power spectra and hemodynamics. Either fentanyl (7 micrograms/kg; n = 30) or sufentanil (1 microgram/kg; n = 30) were given in a randomized fashion to induce anesthesia in heavily premedicated patients, followed by pancuronium bromide (100 micrograms/kg). EEG-power spectra (delta, theta, alpha, beta) as well as mean arterial blood pressure (MAP) and heart rate (HF) were measured at the following end-points: before the induction of anesthesia (control), 1 and 10 minutes after laryngoscopy and intubation (L & I). Linear regression analysis was computed to determine which of the EEG power spectra was most sensitive to detect insufficient blockade of nociceptive-related arousal when correlated with haemodynamics. In the fentanyl group the change in HF closely correlated with the decrease of power in the slow delta- and theta-domain (r2 = 0.98 and r2 = 0.89 respectively) of the EEG. The change in MAP also closely correlated with a decrease in the slow delta- and theta-domain (r2 = 0.97 and r2 = 0.99 respectively). There was little correlation in regard to spectral edge frequency (SEF) and HF and MAP changes (r2 = 0.36 and r2 = 0.12 respectively). In the sufentanil group the change in HF correlated closely with an increase of power in the fast alpha and a decrease in the slow theta-domain (r2 = 0.91 and r2 = 0.98 respectively) of the EEG. The changes in MAP closely correlated with an increase in the fast alpha-band a decrease in the slow theta-domain (r2 = 0.98 and r2 = 0.73 respectively). Also there was little correlation of SEF with HF and MAP changes (r2 = 0.09 and r2 = 0.02 respectively). Among the EEG-spectra, reduction of power in the slow delta- and theta-bands are the most sensitive parameters to determine insufficient antinociception of opioids commonly used for the induction in cardiac anesthesia. Increase of power in the alpha-band seems to be closely correlated with cortical reactivation and reduction of hypnosis, while a reduction of power especially in the deltabut more so in the theta-band of the EEG reflects nociception related arousal.
Routine laryngoscopy can be performed easily and quickly utilizing a right-angle telescope with a specially designed holder. In 1,000 consecutive laryngoscopies done on patients without laryngeal symptoms, abnormalities were found in 173 patients (17.3 percent). Among the abnormalities was an asymptomatic carcinoma which, thanks to early detection, was successfully treated by radiation.
Many researchers have studied esmolol and its effects on heart rate and blood pressure. All studied relatively large doses of esmolol. Therefore, the purpose of the present study was to determine whether small doses of esmolol would blunt the transient increases in blood pressure and heart rate caused by laryngoscopy. This double-blind, prospective, randomized study included 61 subjects. The subjects were randomized to 1 of 3 groups: group 1 received esmolol, 0.2 mg/kg; group 2 received esmolol, 0.4 mg/kg; and group 3 received saline placebo. Groups 1 and 2 had smaller increases in heart rate than group 3. We also found that the 0.4 mg/kg dose significantly blunted the increase in mean arterial pressure seen in group 3. This study shows that small doses of esmolol may block the increases in heart rate and blood pressure resulting from laryngoscopy and intubation.
OBJECTIVE: To evaluate the clinical applications of helical CT multiplanar reformation (MPR), three-dimensional reconstruction (3D) and virtual laryngoscopy (CTVL) in laryngeal and hypopharyngeal carcinoma. METHODS: Axial helical CT scan was performed in 24 patients with laryngeal or hypopharyngeal carcinoma, meanwhile MPR, 3D and CTVL were performed on each patient. The results were compared with the fiberoptic laryngoscopic and surgical findings. RESULTS: Axial helical CT combined with MPR images, the accuracy of preoperative tumor staging and detection of metastatic lymph nodes were both 96%. In 25% of the cases, MPR was more informative than axial images about the extent of tumor invasion. The 3D image three-dimensionally displayed the extent of tumor invasion, and its relation to blood vessels and airway. On CTVL, the location, size and extent of intraluminal tumors of the larynx and hypopharynx when observed from above corresponded well with those observed under laryngoscope. In 4 patients, CTVL observed from below, demonstrated the relationship between the tumor and vocal cords and anterior commissure inaccessible to fiberoptic laryngoscopy. CONCLUSION: Helical CT axial scanning combined with MPR, 3D and CTVL images, can provide more comprehensive information about laryngeal and hypopharyngeal carcinoma.
BACKGROUND: Various tubes have been advocated to deal with airway problems related to operative laryngoscopy. These include large- and small-diameter tubes localized in the supraglottic, subglottic, or transtracheal region. MATERIAL/METHODS: We report our clinical experience with the use of the Benjet tube on 25 patients (23-64 years of age), American Society of Anesthesiologists physical status I and II, who underwent operative laryngoscopy. The Benjet tube was positioned within the trachea using a standard curved laryngoscope. Its proximal end was connected to a jet-ventilation system equipped with a pressure-limiting drive and airway-pressure gauge. A rigid microlaryngoscope was inserted, through which a sampling needle was introduced into the vicinity of the tracheal opening, for end-tidal carbon dioxide determination. Heart rate, non-invasive blood pressure, and hemoglobin oxygen saturation were continuously monitored. RESULTS: The Benjet tube was found to be easy to introduce and remove and was unobtrusive in the larynx and trachea, allowing excellent surgical conditions. Cardiorespiratory parameters were stable and did not change from baseline values. End-tidal carbon dioxide values ranged between 34 and 35 mm Hg. CONCLUSIONS: We conclude that the Benjet tube is highly indicated for operative laryngoscopic procedures.
The objective was to compare the effect of three pharmacological agents on the hemodynamic response to suspended laryngoscopy in micro ENT Surgery. Double blind randomised prospective study having included: groupe A (n = 16) having benefited before laryngoscopy of 150 mcg/kg esmolol, groupe B (n = 16) 15 mcg/kg of nicardipine, groupe C (n = 15) 1 mg/kg of lidocaine and groupe D (n = 16), placebo group. All groups were comparable for demographic and anesthetic data. A significant reduction of the heart rate and pressure rate product were noted in esmolol group during the endoscopic act and maintained until arousal. Whereas there was no difference in the blood pressure during the procedure whatever the pharmacological agent for prevention of cardiovascular complications for patients to risk in micro ENT surgery.
Many medical procedures require fine motor skills, and these skills are developed over years of practice and through performing hundreds to thousands of procedures. However medical training that is based upon gaining this expertise by performing procedures on patients results in unnecessary risk to the patient. In this project expert medical skill is quantified, so that advanced medical simulators can be created to provide a realistic training environment. This approach is applied to airway intubation with a rigid laryngoscope; a procedure that is performed prior to general anesthesia and during emergency situations. A laryngoscope has been instrumented with a 3 dimensional force/torque sensor, and magnetic position sensors have been placed on the laryngoscope and the patient. Measurements are made in the operating room of both experts and novices as they perform laryngoscopy on consenting patients undergoing general anesthesia. The skill of the laryngoscopist is represented by the motion and force trajectories applied to the laryngoscope during the procedure. Preliminary results show that novices often err in the placement of the tip of the laryngoscope blade. However, when two experts perform laryngoscopy on the same patient, both experts perform key elements of the task consistently. The measured consistency among experts indicates that it will be possible to apply algorithms developed for Human Skill Acquisition, and thereby define regions of expert motion relative to patient anatomy. This is the first step in developing advanced training simulators that will simulate the procedure accurately, provide guidance to the trainee, and can be used for assessment of medical skill.
Effect of diltiazem on cardiovascular response to laryngoscopy and tracheal intubation was studied in 20 patients without hypertension and 10 patients with hypertension to be operated on under general anesthesia. The patients were divided into three groups: the first group without hypertension (group C, n = 10) received saline as control, the second group without hypertension (group N, n = 10) received bolus injection of diltiazem, and the third group with hypertension (group H, n = 10) received bolus injection of diltiazem. Diltiazem was administered 2 min before intubation at a dose of 0.2 mg.kg-1 as a bolus injection. Changes of mean blood pressure, rate pressure product, pressure rate quotient in group H and N decreased significantly compared with group C. Changes of heart rate were comparable among the three groups. Complications were not remarkable except one case in which systolic pressure decreased to 80 mmHg. The results suggest that bolus injection of diltiazem at a dose of 0.2 mg.kg-1 attenuates cardiovascular response to laryngoscopy and tracheal intubation without serious complications.
Neonatal laryngoscopy and endotracheal intubation often are required for prematurely born, low birthweight children. Previous studies have shown that these procedures are associated with a high prevalence of enamel hypoplasia of the maxillary anterior teeth. The present case report, which describes dilaceration of a left maxillary primary central incisor probably resulting from laryngoscopy, strongly supports the hypothesis that irreversible trauma to the dentition may result from endotracheal intubation.
A material of 36 patients to be submitted to direct laryngoscopy was subdivided at random in a double blind investigation to total intravenous anaesthesia with metohexitone or thiopentone. Alfentanil was employed as an analgesic and relaxation was obtained with vecuronium. The anaesthesia was maintained with continuous barbiturate infusion and supplementary alfentanil and vecuronium. The patients in the metohexitone group showed significantly faster recovery with an average of seven minutes as compared with 20 minutes in the thiopentone group and significantly more had Glasgow coma scores of over 12 after 30 minutes. After 60 and 90 minutes, no significant differences could be demonstrated between the groups. It is concluded that thiopentone is unsuitable for total intravenous anaesthesia for direct laryngoscopy whereas metohexitone was particularly suitable. Metohexitone is proposed as an alternative to the more recent and more expensive propofol. The frequency of pain on injection of metohexitone does not differ from that with propofol and this may be reduced by employing a vein in the cubital fossa instead of a vein on the dorsum of the hand.
For the direct laryngoscopy and microscopic examination of the larynx with exploratory excision and pulpectomy using low frequency jet-ventilation with 100% oxygen we used total intravenous anaesthesia with a strong acting opioid and a barbiturate. Because the achievement of sufficient reflexes and a high degree of vigilance postoperatively are to be aimed, Methohexitone (M) and Thiopentone (T) were investigated in the regard of the suppression of vigilance in the postoperative period. 40 patients were randomly assigned to the group M (n = 20) or T (n = 20). The evening before operation, an intelligence test and a syndrome-short-test (SST) were performed for the measurement of attention and memory (functional psychosis). The patients received 2 mg Flunitrazepam orally and transdermal Scopolamine. On the day of operation the patients received 1 mg Lormetazepam orally for premedication. Anaesthesia was induced with 2 mg Alcuronium, 1 mg Alfentanil, 1.4 mg/kg bodyweight M respectively 5 mg/kg bodyweight T and 1.4 mg/kg bodyweight Succinylcholine. Immediately before laryngoscopy the patients received 2-4 mg Alfentanil. Muscle relaxation was achieved by an infusion with Succinylcholine using relaxometry. Methohexitone respectively Thiopentone were administered by infusion depending on clinical signs indicating insufficient anaesthesia. The following parameters were measured: Blood pressure, heart rate, duration of operation and anaesthesia, parameters of vigilance 30, 60 and 120 minutes after operation (SST) and the ability of performance. The groups were comparable with respect to all data except the parameters of vigilance. The patients receiving M were significantly more vigilant 30 min., 60 min. (SST) and 120 min (SST) after the end of anaesthesia than patients receiving T (p = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
The following case report describes a patient who suffered an anterior maxillary alveolar ridge fracture resulting from difficult laryngoscopy and intubation. An unfortunate sequelae of this injury was the loss of two maxillary central incisors due to persistent mobility despite long term dental stabilization. To the authors' knowledge, fractures involving the premaxilla have not been reported as a complication of laryngoscopy and intubation.
Oropharyngeal topical anesthesia with viscous lidocaine (25 ml of 2% as a "mouthwash and gargle" 10 min before laryngoscopy) attenuated the pressor but not heart rate (HR) response during laryngoscopy and tracheal intubation. Compared with control patients, mean arterial pressure (MAP) increased less in response to tracheal intubation (23 +/- 5 torr versus 39 +/- 4 torr, p less than 0.05) and returned toward awake levels sooner in patients receiving viscous lidocaine. MAP increased more than 40 torr in response to intubation in 6/20 patients treated with viscous lidocaine, while 12/20 control patients manifested this degree of blood pressure elevation. HR increased about 20 bpm (p less than 0.05) with or without viscous lidocaine. Arterial lidocaine concentrations were less than 0.5 microgram/ml after oropharyngeal anesthesia. Prior topical anesthesia of the oropharynx with viscous lidocaine should be considered when pressor responses during tracheal intubation would be particularly likely or hazardous.
Examination of the larynx is neglected as a regular part of the physical examination by many physicians, largely because of difficulties inherent in the angled-mirror technique of visualizing this area. Simple, relatively inexpensive right-angle telescopes especially designed for laryngoscopy are now available to facilitate this examination. In one study, abnormalities were found in 17 percent of consecutive asymptomatic patients receiving laryngoscopy. This procedure has an important role as a screening procedure and as a diagnostic aid in the workup of patients with laryngeal symptoms. The technique can be readily learned and used in everyday medical practice.
High pressure oxygen jet ventilation via a small bore endotracheal tube has been found to be a very effective method for operative laryngoscopy and bronchoscopy under general anesthesia. Advantages of this technique include easily visualization of the larynx and good access for surgical manipulations and bronchoscopic procedures while maintaining excellent patient oxygenation and ventilation. There are few contra-indications for this procedure. Over the past 7 years we have done several thousand operative laryngoscopies using high pressure oxygen jet ventilation with few complications and excellent anesthetic and surgical results.