Comparison of the effect of dexmedetomidine and midazolam under spinal anesthesia for cesarean delivery: a randomized controlled trial, single center study in South Korea

Background@#Cesarean section under spinal anesthesia may cause anxiety and hypotension. Administration of sedative drugs after delivery can diminish these side-effects, but may increase hemodynamic instability. We evaluated the effect of the administration of 0.7 μg/kg dexmedetomidine and compared it with that of 0.03 mg/kg midazolam for usefulness of sedation of the parturient after delivery during cesarean section. @*Methods@#After obtaining written consent and the ethics board approval, 60 parturients aged 20–43 years who underwent elective cesarean delivery under spinal anesthesia were recruited. A total of 0.5% hyperbaric bupivacaine (8–10 mg) and intrathecal fentanyl (10 μg) was given to induce anesthesia. Parturients were then randomly allocated to receive either midazolam (0.03 mg/kg; group M) or dexmedetomidine 0.7 (μg/kg; group D) after delivery. The primary outcome measure was patient satisfaction score. Secondary outcomes included vital signs; vasopressor dosage; incidence of shivering, nausea, and vomiting; incidence of bradycardia; time to sensory and motor recovery; postoperative nausea and vomiting score; and postoperative pain visual analog scale at 6, 24, and 48 h. @*Results@#Satisfaction scores for sedation were similar between the two groups. The systolic blood pressure, heart rate, oximetry saturation, and tympanic temperature were comparable between the two groups. The predicted mean systolic blood pressure of group D was 106.3 mmHg and that of group M was 107.5 mmHg. Both groups showed comparable adverse intraoperative and postoperative outcomes. @*Conclusions@#Dexmedetomidine and midazolam showed similar hemodynamic effects and patient satisfaction in parturients under spinal anesthesia.

Bilateral complex arytenoid dislocation

No abstract available.

Polymyxin B Immobilized Fiber Hemoperfusion in Refractory Intra-abdominal Septic Shock / 대한구급학회지

The effects of direct hemoperfusion with polymyxin B immobilized fiber (PMX) treatment for septic shock have been recently reported. However, little evidence of a true benefit on clinical outcomes, including mortality, is available. Herein, we report three cases of intra-abdominal infection associated with refractory septic shock Case 1 was Escherichia coli peritonitis after a colectomy. PMX treatment improved the hemodynamic parameters and lactic acid levels of the patient. In case 2, secondary peritonitis was associated with septic or cardiogenic shock. Septic cardiomyopathy was assumed to be the cause of shock. 24 hours after the use of PMX, cardiac contractility assessed by echocardiography returned to baseline. In case 3, a patient with Burkitt's lymphoma and neutropenia was found to be gastroenteritis and Klebsiella pneumoniae bacteremia. Intravenous meropenem was administered for 3 days. Hemodynamic parameters improve after the twice use of PMXOverall, the change of serial sequential organ failure assessment score (SOFA) was more significant in surgical cases as compared to the medical case at 72 hours after PMX administration. All patients were discharged from the hospital. In addition to early resuscitation efforts and infection source control, PMX treatment may be beneficial to patients with refractory intra-abdominal infection associated with septic shock.

Polymyxin B Immobilized Fiber Hemoperfusion in Refractory Intra-abdominal Septic Shock / 대한중환자의학회지

The effects of direct hemoperfusion with polymyxin B immobilized fiber (PMX) treatment for septic shock have been recently reported. However, little evidence of a true benefit on clinical outcomes, including mortality, is available. Herein, we report three cases of intra-abdominal infection associated with refractory septic shock Case 1 was Escherichia coli peritonitis after a colectomy. PMX treatment improved the hemodynamic parameters and lactic acid levels of the patient. In case 2, secondary peritonitis was associated with septic or cardiogenic shock. Septic cardiomyopathy was assumed to be the cause of shock. 24 hours after the use of PMX, cardiac contractility assessed by echocardiography returned to baseline. In case 3, a patient with Burkitt's lymphoma and neutropenia was found to be gastroenteritis and Klebsiella pneumoniae bacteremia. Intravenous meropenem was administered for 3 days. Hemodynamic parameters improve after the twice use of PMXOverall, the change of serial sequential organ failure assessment score (SOFA) was more significant in surgical cases as compared to the medical case at 72 hours after PMX administration. All patients were discharged from the hospital. In addition to early resuscitation efforts and infection source control, PMX treatment may be beneficial to patients with refractory intra-abdominal infection associated with septic shock.

The Effects of a Single Bolus of Remifentanil on Corrected QT Interval Change during Sevoflurane Induction

PURPOSE: Opioids may affect changes in the corrected QT interval (QTc) during anesthetic induction. This study examine whether a single bolus of remifentanil would prolong QTc after laryngeal mask airway (LMA) insertion during sevoflurane induction. MATERIALS AND METHODS: Forty women of American Society of Anesthesiologists physical status 1 (ASA PS1) undergoing gynecological surgery were studied. All patients were induced using three vital capacity inhalation inductions with 5% sevoflurane. Two minutes after induction, the inspiratory concentration of sevoflurane was reduced to 2%. Using double-blinded randomization, patients were allocated into one of two groups, receiving either saline (placebo group, n = 20) or 0.25 microg.kg-1 remifentanil (remifentanil group, n = 20) over a period of thirty seconds. Sixty seconds later, LMA insertion was performed. Recordings were taken with a 12-lead electrocardiogram at baseline, 2 min after induction and 1 and 3 min after LMA insertion. QTc was calculated by Bazett's formula. The mean arterial pressure (MAP) and heart rate (HR) were also measured at each time point. RESULTS: The QTc interval was significantly prolonged in the placebo group as compared to the remifentanil group at 1 min after LMA insertion (467.8 +/- 16.5 vs. 442.7 +/- 21.3 ms, p < 0.001). However, there was no significant difference in QTc at 3 min after LMA insertion between the two groups. MAP and HR were significantly higher in the placebo group (p < 0.001). CONCLUSION: A single bolus of remifentanil is safe method to attenuate prolonged QTc associated with insertion of LMA.

Effect of remifentanil on tumor necrosis factor-alpha and interleukin-6 responses in patients undergoing laparoscopic hysterectomy

BACKGROUND: Cytokines are important mediators of immune response to surgery and pain.The aim of the study was to investigate the effect of remifentanil on serum levels of cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), in patients undergoing laparoscopic hysterectomy. METHODS: Twenty four patients scheduled for laparoscopic hysterectomy were randomly assigned to control or remifentanil group.Both groups received 1.5-2.5% end tidal concentration of sevoflurane and air in 50% oxygen.Remifentanil group received a bolus of remifentanil 1microgram/kg over 1 min and an infusion of remifentanil at a rate of 0.1microgram/kg/min.Control group received 10 ml saline (placebo) and an infusion of saline at the same rate. Venous blood samples for measurement of serum cytokine concentrations were taken before anesthesia (T1), at 2 h after infusion (T2), and at the 1 hour after surgery (T3). RESULTS: Serum TNF-alpha concentration did not differ significantly over time in both groups.Serum TNF-alpha concentration was higher in remifentanil group at T3 (9.76 +/- 1.19 pg/ml vs.8.53 +/- 0.71 pg/ml) than in control group (P < 0.05). In both groups, serum IL-6 concentrations were significantly higher at T3, when compared to those at T1 and T2 (P < 0.05). CONCLUSIONS: Remifentanil did not attenuate early postoperative change of serum TNF-alpha and IL-6 concentrations in patients undergoing laparoscopic hysterectomy. Serum IL-6 level increased at postoperative 1 h, regardless of remifentanil use.

Anesthetic Management of Acute Massive Pulmonary Embolism after Intracerebral Hemorrhage: A case report / 대한마취과학회지

Acute massive pulmonary embolism after intracerebral hemorrhage (ICH) is rare but associated with a high mortality rate. A 44-year-old man presented with acute pulmonary embolism on 38th day after onset of ICH. We tried off-pump pulmonary embolectomy with CPB on stand-by. But, hemodynamic deterioration occurred when right pulmonary artery was clamped after removal of some clots, therefore CPB was rapidly instituted under normothermic beating heart with full heparinization. On pump beating, heart pulmonary embolectomy was performed successfully without adverse events. On postoperative 2nd day, the patient was started on anticoagulation therapy and recovered favorably without any neurologic sequelaes.

C-arm guided placement of Fogarty embolectomy catheter for one lung ventilation in an infant: A case report / 대한마취과학회지

We experienced one lung anesthesia using Fogarty embolectomy catheter as a bronchial blocker in an infant undergoing thoracotomy for foreign body removal. For the guidance of catheter placement in left mainstem bronchus, C-arm fluoroscopy was used. Size of catheter and its balloon was decided beforehand by measuring the diameter and length of bronchus based on the view obtained from computerized tomography. There was no accidental episode during anesthesia. C-arm fluoroscopy is safe and useful method to decide the position of Fogarty occlusion catheter in an infant.

Comparison of clinical effect of intrathecally administered fentanyl for elderly patients undergoing urologic surgery / 대한마취과학회지

BACKGROUND: Spinal anesthesia for urologic surgery in elderly patients is preferred. The addition of opioids to local anesthetics reduces the side effects of spinal anesthesia. This study examined the effects of intrathecal fentanyl 10microgram and 20microgram when administered with hyperbaric 0.5% bupivacaine to elderly patients undergoing urologic surgery. METHODS: Forty-five elderly patients undergoing urologic surgery were randomized into the following three groups: group 1, bupivacaine 7.5 mg; group 2, bupivacaine 5 mg + fentanyl 10microgram; and group 3, bupivacanie 5 mg + fentanyl 20microgram. The total volume of intrathecally injected was adjusted to 1.5 ml with sterile normal saline. Spinal anesthesia was administered with a 25 G Quincke needle at the L3-4 or L4-5 interspace in the lateral position. The neural block was assessed using a pinprick test and the Bromage scale. RESULTS: There were no significant differences in the onset time of the T10 sensory block, peak level of the sensory block, and onset time of the peak level. The duration of the sensory block was significantly shorter in group 2 than in group 1 (P = 0.017). The duration of the motor block was longer in group 1 than in groups 2 and 3 (P = 0.016, P = 0.04). Pruritus was observed more often in group 3 (37.5%) and shivering was more common in group 1 (P = 0.005). CONCLUSIONS: The addition of fentanyl 10microgram and 20microgram to bupivacaine 5 mg provides adequate anesthesia for elderly patients undergoing urologic surgery with fewer side effects, and fentanyl 10microgram is recommended as outpatient anesthesia.

Comparison of clinical effect of intrathecally administered fentanyl for elderly patients undergoing urologic surgery / 대한마취과학회지

BACKGROUND: Spinal anesthesia for urologic surgery in elderly patients is preferred. The addition of opioids to local anesthetics reduces the side effects of spinal anesthesia. This study examined the effects of intrathecal fentanyl 10microgram and 20microgram when administered with hyperbaric 0.5% bupivacaine to elderly patients undergoing urologic surgery. METHODS: Forty-five elderly patients undergoing urologic surgery were randomized into the following three groups: group 1, bupivacaine 7.5 mg; group 2, bupivacaine 5 mg + fentanyl 10microgram; and group 3, bupivacanie 5 mg + fentanyl 20microgram. The total volume of intrathecally injected was adjusted to 1.5 ml with sterile normal saline. Spinal anesthesia was administered with a 25 G Quincke needle at the L3-4 or L4-5 interspace in the lateral position. The neural block was assessed using a pinprick test and the Bromage scale. RESULTS: There were no significant differences in the onset time of the T10 sensory block, peak level of the sensory block, and onset time of the peak level. The duration of the sensory block was significantly shorter in group 2 than in group 1 (P = 0.017). The duration of the motor block was longer in group 1 than in groups 2 and 3 (P = 0.016, P = 0.04). Pruritus was observed more often in group 3 (37.5%) and shivering was more common in group 1 (P = 0.005). CONCLUSIONS: The addition of fentanyl 10microgram and 20microgram to bupivacaine 5 mg provides adequate anesthesia for elderly patients undergoing urologic surgery with fewer side effects, and fentanyl 10microgram is recommended as outpatient anesthesia.

The Effect of the Level of Sedation on Recovery in Patients undergoing Target Controlled Propofol Infusion with a Bolus of Fentanyl for Strabismus Surgery / 대한마취과학회지

BACKGROUND: An immediate examination of ocular movement is required during strabismus surgery. The aim of this study was to determine the effect of the level of sedation on the recovery of patients undergoing a target controlled propofol infusion with a bolus of fentanyl for strabismus surgery. METHODS: Twenty-one outpatients scheduled to undergo strabismus surgery were assigned randomly to one of two groups. In both groups, sedation was induced with a bolus of fentanyl 1microgram/kg intravenously followed by an infusion of propofol with a target concentration of 1.0microgram/ml. The target concentration was increased or decreased by 0.1 microgram/ml steps until the patient reached and maintained the observer's assessment of alertness/sedation (OAA/S) scale score of 3 (group A) or 4 (group B). The supplemental analgesics consisted of fentanyl 25-50microgram bolus injection. The target concentration of propofol, the total dose of fentanyl, delayed awakening, and recovery time were recorded. RESULTS: The mean target concentration of propofol (mean +/- SD) in group A (1.8 +/- 0.4microgram/ml) was significantly higher than that of group B (1.3 +/- 0.4microgram/ml) (P<0.05). There were no significant differences in the total dose of fentanyl, delayed awakening and recovery time between the two groups. There was an an increasing trend in the recovery time with the total dose per kilogram of body weight of fentanyl (Spearman's correlation coefficient, r = 0.384, P = 0.086). CONCLUSIONS: The levels of sedation did not affect the recovery time in patients during target propofol infusion with a bolus of fentanyl. However, the addition of fentanyl tended to prolong the recovery time.

The Erythrocyte 2,3-diphosphoglycerate Concentration and Its Related Factors in Patients with End-stage Liver Disease / 대한마취과학회지

BACKGROUND: It is believed that an increase in the level of erythrocyte 2,3-diphosphoglycerate is an important compensatory mechanism that allows satisfactory tissue oxygenation in hypoxic patients. This study measured the level of 2,3-diphophoglycerate and the factors affecting its concentration, as well as the position of the oxygen-hemoglobin dissociation curve in patients with end-stage liver disease. METHODS: Fifty patients receiving liver transplantation (experimental group) and forty-five healthy donors (control group) were enrolled in this study. Arterial-mixed venous oxygen content difference, whole body oxygen delivery and consumption were measured after determining the hemodynamic parameters including cardiac output in the experimental group. The erythrocyte 2,3-diphosphoglycerate level was measured using assay procedures. The P50 value was used to determine the position of the oxygen-hemoglobin dissociation curve. RESULTS: The 2,3-diphosphoglycerate level was higher in patients with end-stage liver disease than in the controls. A 0.3 g/L increase in the 2,3-diphosphoglycerate concentration corresponded to a P50 increase in 1.2 mmHg with a rightward displacement of the oxygen-hemoglobin dissociation curve. The 2,3-diphosphoglycerate concentration showed a significant correlation with the PaO2, Ca-vO2, P50, and blood lactate level, but not with the hemodynamic parameters such as the cardiac index, oxygen delivery index, and pH. CONCLUSIONS: End-stage liver disease is associated with an increase in the level of the erythrocyte 2,3-diphosphoglycerate and P50. This is believed to be an important compensatory mechanism to allow better tissue oxygenation. An increase in the 2,3-diphosphoglycerate level correlates well with the oxygenation parameters, rather than with the hemodynamic parameters.

Assessment of Blood Glucose Values Measured by Blood Gas Analyzer or Portable Glucometer / 대한마취과학회지

BACKGROUND: A portable glucometer is commonly used to immediately check the blood glucose level. In the anesthetic field, some blood gas analyzers can also give a rapid indication of the blood sugar level but the accuracy is unknown. Therefore, this study assessed the accuracy of the blood glucose values measured by either a blood gas analyzer or portable glucometer. METHODS: Venous blood from diabetic patients was used to measure the glucose level with either a blood gas analyzer or a portable glucometer. The difference and 5% deviation from reference values was analyzed. These values were also assessed using a Bland-Altman plot and clinical significance was examined using a Clarke error grid. RESULTS: The differences from the reference values were smaller using the blood gas analyzer (1.3 +/- 7.8 mg/dl) than using the portable glucometer (-5.1 +/- 16.7 mg/dl)(P < 0.01). 73.4% of the values measured by the blood gas analyzer and 40.0% of those measured by the portable glucometer were within 5% of the reference value. The 95% limits of agreement in the difference ranged from -14.3 to 16.9 in the blood gas analyzer and -38.5 to 28.2 in the portable glucometer. Error grid analysis showed that 100% of the values measured by the blood gas analyzer were located in zone A. When locating the values measured using the portable glucometer, 95.6% were located in zone A, and the remaining 4.4% are located in zone B. CONCLUSIONS: The blood gas analyzer measures the blood glucose more accurately than the portable glucometer. However, the blood glucose values measured by the portable glucometer are clinically acceptable.

Anesthetic Management in a Patient with Charcot-Marie-Tooth Disease: A case report / 대한마취과학회지

A 35-year old woman was scheduled to undergo a total hystectomy due to uterine myoma. She had been diagnosed with Charcot-Marie-Tooth disease 2 years ago. In addition, she had previously received a Cesarean section under epidural anesthesia 10 years ago and reported a prolonged motor blockade at that time. General anesthesia was induced with propofol 120 mg in a divided dose and the intubating condition was achieved with vecuronium 3 mg. Anesthesia was maintained with 1.5-2.5% enflurane with air and O2. During surgery, the body temperature and end tidal concentration of CO2 were maintained within the normal range. Despite the continuous monitoring of the train-of-four (TOF) response, no more muscle relaxants were required during surgery and the patient recovered without a delay in awakening. In the management of patients with Charcot-Marie-Tooth disease, it is desirable to evaluate the patient carefully, select the appropriate anesthetics and adjust the dosage of the drug according to the patients requirements.

The Effect of Combined Fentanyl and Ketamine Administration in the Monitored Anesthetic Care of Ambulatory Strabismus Surgery / 대한마취과학회지

BACKGROUND: Monitored anesthetic care can provide patient safety and optimal surgical conditions. However, propofol and fentanyl decrease the hypoxic ventilatory response and heart rate. Ketamine has less respiratory depression and blocks bradycardia. Furthermore, ketamine can reduce the amount of opioid use but it delays discharge in the outpatient anesthesia. Therefore, this study retrospectively examined the effects of combined fentanyl and ketamine administered during monitored anesthetic care on the use of opioids, cardiorespiratory side effects, and patient discharge. METHODS: The anesthetic room, the recovery room and day surgery center records of ambulatory strabismus surgery with monitored anesthetic care was reviewed by anesthesiologists from Oct. 2004 to July 2005. The patients were classified as those receiving either fentanyl (F group: n = 32) or fentanyl and ketamine (FK group: n = 19) with a propofol infusion. The fentanyl dose used, the need for airway support, anticholinergics and naloxone were compared. The stay in the recovery room and the day surgery center was also examined. RESULTS: The FK group used significantly less fentanyl than the F group (P < 0.05). Although airway support was needed, there was less anticholinergics and naloxone used in the FK group, but this difference was not significant. The stay in recovery room and the day surgery center were similar. CONCLUSIONS: Co-administered ketamine reduces the amount of fentanyl-needed, but it does not reduce the need for airway support and anticholinergics. In addition, co-administered ketamine does not affect the number of days in the recovery room and day surgery center.

Evaluation of Mechanical Ventilation and Its Influencing Factors between the Living Related Liver Transplantation and Cadaveric Whole Liver Transplantation / 대한마취과학회지

BACKGROUND: Postoperative pulmonary complications are amongst the greatest causes of morbidity and mortality during liver transplantation. Postoperative mechanical ventilation and tracheal extubation are important parts of postoperative critical care. However, there are no comparative studies on postoperative mechanical ventilation, duration of intensive care units admission between cadaveric whole liver transplantation and living related liver transplantation groups, which are different from anesthetic and surgical procedures. In our present study, we have compared mechanical ventilation, duration of ICU admission and its influencing factors between the two groups. METHODS: We have retrospectively studied 67 cases and depending on the surgical procedures, we divided them into two groups; control group undergoing cadaveric whole liver transplantation and experimental group undergoing living related liver transplantation. Each group was evaluated based on operation time, time of mechanical ventilation, duration of ICU admission, amounts of infused fluid and transfusion during operation, preoperative and extubation O2 index, serum creatinine levels, and preoperative and intraoperative risk score. RESULTS: The mechanical ventilation time in experimental group was observed to be shorter than in control group, and serum creatinine level during the 3rd postoperative day in experimental group was lower than in control group (P<0.05). However, there was no difference in duration of ICU admission, O2 index, fluid amount and transfusion, and risk score between the two groups. CONCLUSIONS: We conclude that living related liver transplantation reduces mechanical ventilation time with no effect on ICU admission periods. Higher risk score is correlated with prolongation of postoperative mechanical ventilation.

Anesthetic Management of Small Bowel Transplantation for Short Bowel Syndrome: A case report / 대한마취과학회지

General treatment of short bowel syndrome is long-term total parenteral nutrition (TPN). But long-term TPN therapy produces thrombus, infection and obstruction of central veins and results in the life-threatening complications. Recently we experienced first case of small bowel transplantation in a 57-year old female with only 30 cm jejunum and distal part of colon to the splenic flexure who was suffering short bowel syndrome due to previous wide resection of small bowel. We report successful anesthetic management of small bowel transplantation in the patient with short bowel syndrome who has been suffered from life threatening complications due to long-term TPN therapy.

The Effect of Ketamine for Pain on Rocuronium Injection Pain / 대한마취과학회지

BACKGROUND: Rocuronium can cause pain on injection in awake patients. We compared the effect of ketamine at three different small doses (0.1 mg/kg, 0.2 mg/kg, 0.3 mg/kg) and saline (placebo) for reducing pain on injection in awake patients. METHODS: 80 patients (aged 19-63 yr) scheduled for elective surgery were randomized to four groups in double-blind manner. Patients received the study drug intravenously, with venous occlusion for 20 seconds, followed by rocuronium 0.6 mg/kg into the dorsal vein over 10 seconds. Patient's response torocuronium injection was graded by four-point verbal rating scale. RESULTS: The incidence of pain was significantly less in patients receiving ketamine 0.3 mg/kg (55%) than in patients receiving saline (85%)(P < 0.05). But, No difference was found between ketamine 0.1 mg/kg, 0.2 mg/kg and saline groups. The pain score was significantly less in patients receiving ketamine 0.2 mg/kg and 0.3 mg/kg than in patients receving saline (P < 0.05). CONCLUSIONS: We concluded that pretreatment of ketamine 0.3 mg/kg with venous occlu-sion for 20 seconds, effectively decreases the incidence of pain caused by rocuronium injection.

Effect of Morphine on c-fos Expression of Incisional Pain Rat Brain / 대한마취과학회지

BACKGROUND: Not many recent studies have shown that morphine antinociception may be directly expressed in forebrain structures. It is generally accepted that c-fos is a marker of neuronal activity and its expresson is correlated with nerve pathway activated by nociceptive stimuli. The aim of this study is to examine the effect of morphine on c-fos expression in the incisional pain rat brain. METHODS: A 1 cm longitudinal incision was made through the skin, fascia and muscle of the plantar aspect of the hindpaw in enflurane-anesthetized rats. 10 mg/kg of morphine was injected intraperitoneally 1 hour before (pre-morphine group; n = 15) and 30 minutes after surgery (post-morphine group; n = 15). The same amount of saline was injected 30 minutes after surgery (control group; n = 15). Two hours later c-fos protein expressions in the thalamus, hypothalamus, cerebral cortex and amygdala were examined by immunohistochemistry using a specific antibody. RESULTS: Numerous c-fos positive cells were observed in thalamus, hypothalamus, cerebral cortex, and amygdala in all groups. There were no significant differences in c-fos expression between pre-morphine, post-morphine and control group (P <0.05). CONCLUSIONS: In this study we expected to decreased c-fos expression in incisional pain rat brain by morphine injection. But no differences were observed compared to control group in thalamus and cortex which transmitting pain to CNS, also in hypothalamus and amygdale which transmitting emotional stress to CNS. These results suggests that intraperitoneal morphine can not protect the c-fos expression of ascending pathway to thalamus, hypothalmus, amygdala and cerebral cortex. Also we can not support the effect of morphine on the descending pathway of pain. So we thought for the more information, additional study, for example, behavior test, PCR (polymerase chain reaction)study, may be needed.

The Usefulness of Preoperative Airway Characteristics as Predictors of Dental Trauma during Laryngoscopy / 대한마취과학회지

BACKGROUND: Damage to teeth has long been associated with endotracheal intubation. But, no rules designed to predict dental injuries have been formulated. In this prospective study, we undertook to identify relationships between anatomic airway measurements used customarily in bedside practice, and blade-tooth distance during laryngoscopy, to assess the usefulness of these anatomic measurements as predictors of dental injury. METHODS: Four hundred and eighty-three patients scheduled for elective surgery requiring general anesthesia with endotracheal tube placement were included. During a preoperative visit, a number of measurements and assessments of features that might predict difficult intubation were performed. When optimum visibility of the glottis was obtained during laryngoscopy, the distance between the flange of the blade and the upper incisor was measured. We determined which of the individual airway characteristics correlated with the blade-tooth distance and best predicted the potential of dental injury. RESULTS: The blade-tooth distance was found to correlate with the individual scales of the Mallampati classification (Spearman's correlation coefficient, r = - 0.356, P < 0.01), mandibular protrusion (r = - 0.390, P < 0.01), head and neck movement (r = - 0.276, P < 0.01), interincisor gap (r = - 0.648, P < 0.01), and the condition of the upper teeth (r = - 0.313, P < 0.01). The frequency of direct blade-tooth contact significantly increased as the scales of these five anatomic measurements increased (P < 0.01). CONCLUSIONS: This study shows for the first time that some airway measurements are correlated with blade-tooth distance, and that they can be considered as useful predictors of dental injury during laryngoscopy.