Comparison of the streamlined liner of the pharynx airway (SLIPA™) with the I-gel™ in paralyzed, anesthetized patients

BACKGROUND: I-gel™ and Streamlined Liner of the Pharynx Airway (SLIPA™) are the second generation supraglottic airway devices characterized by disposability and non-inflatable cuff that provide adequate sealing pressure and easy use. This study was designed to compare oro-pharyngeal leakage pressure of the I-gel™ with the SLIPA™. METHODS: Seventy-eight adult patients were randomly assigned to undergo general anesthesia with either I-gel™ or SLIPA™. Hemodynamic changes and Oro-pharyngeal leakage pressure were assessed at one minute after the insertion. The total insertion time, number of attempts, ease of insertion, and presence of blood staining and regurgitation were recorded. After surgery, postoperative sore throat and other complications (dysphonia, dysphagia or paresthesia of tongue) were evaluated. RESULTS: Oro-pharyngeal leakage pressure after device insertion was higher in the SLIPA™ group than the I-gel™ group. Insertion time was significantly shorter in the I-gel™ group than the SLIPA™ group. Blood staining was presented in 21.1% of the SLIPA™ group vs. 2.6% of the I-gel™ group. In the recovery room, postoperative sore throat measured in visual rating scale (VAS) was significantly higher in the SLIPA™ group than in the I-gel™ group. Ease of insertion, regurgitation, respiratory index and hemodynamic change after insertion showed no significant differences. CONCLUSIONS: In this study, the SLIPA™ devices provided higher oro-pharyngeal leakage pressure than I-gel™. However, the results verified ease of insertion, and safety of ventilation and hemodynamic changes, without any severe complications in both I-gel™ and SLIPA™.

A comparative study among normal saline, water soluble gel and 2% lidocaine gel as a SLIPA lubricant / 대한마취과학회지

BACKGROUND: This study was designed to find appropriate lubricant for streamed lined liner of pharyngeal airway(TM) (SLIPA(TM)). We evaluated the incidence of sore throat, nausea, vomiting, hoarseness, paresthesia and blood stain after using saline, water soluble gel and 2% lidocaine gel as a SLIPA(TM) lublicant. METHODS: One hundred twenty three patients scheduled for minor surgery to whom the SLIPA(TM) was considered suitable were randomly allocated to one of three groups which receive normal saline, water soluble gel or 2% lidocaine gel as a SLIPA(TM) lublicant. Patients were interviewed at recovery room, post operation 6-12 hour, post operation 18-24 hour about sore throat and other complications. RESULTS: There were no statistical difference in sore throat and blood stain among three groups. Also there were no statistical differences in hoarseness, nausea, vomiting. The incidence of paresthesia in 2% lidocaine gel group was significantly higher than those of the other two groups immediately after operation, but it was resolved after leaving the recovery room. CONCLUSIONS: Our results suggest that normal saline, water soluble gel and 2% lidocaine gel are all available as a SLIPA(TM) lubricant. Size of SLIPA(TM), insertion technique and difficulty of insertion should be further investigated as the main causes of a sore throat and other complications which can occur after the insertion of SLIPA(TM).

Ultrasound-Guided Infraorbital Nerve Pulsed Radiofrequency Treatment for Intractable Postherpetic Neuralgia: A Case Report

A 60-year-old man presented with pain on the left cheek and lateral nose. The patient had been diagnosed with facial herpes zoster in the left V2 area 6 months previously. Medical treatment was prescribed for 6 months but it had little effect. We blocked the left infraorbital nerve under ultrasound guidance, but pain relief was short term. Therefore, we performed pulsed radiofrequency treatment on the left infraorbital nerve under ultrasound guidance. Six months after the procedure, the reduction of pain was still maintained, and there was no need for further management.

Intractable Hemifacial Spasm Treated by Pulsed Radiofrequency Treatment

Hemifacial spasm is defined as unilateral, involuntary, irregular twitching of all or parts of the muscles innervated by facial nerves. Here, we present a case of recurrent hemifacial spasm after microvascular decompression (MVD) treated with pulsed radiofrequency (PRF) treatment with good results. A 35-year-old woman suffered from recurrent hemifacial spasm after MVD that was refractory to medical treatment and botulinum toxin injections. We attempted a left facial nerve block twice. Then, we applied PRF at a maximum temperature of 42degrees C for 120 sec. Some response was observed, so we applied PRF two additional times. The frequency of twitch decreased from 3-4 Hz to < 0.5 Hz, and subjective severity on a visual analogue scale also decreased from 10/10 to 2-3/10. PRF treatment might be an effective medical treatment for refractory hemifacial spasm and has fewer complications and is less invasive compared with those of surgery.

The causes of difficult tracheal intubation and preoperative assessments in different age groups / 대한마취과학회지

BACKGROUND: We studied the differences in airway assessment factors among old, middle, and young age groups, and evaluated the frequency and causes of difficult intubation among these groups. METHODS: Patients were divided into young ( or = 60 yr, n = 89) group. Airway assessment factors such as head and neck movement, thyromental distance, interincisor gap, dentition, Mallampati score, and Arne score were assessed. After muscle relaxation, cervical joint rigidity and Cormack-Lehane (C-L) grade were assessed. The differences in airway assessment factors between difficult (C-L grade 3, 4) and easy (C-L grade 1, 2) intubation were then examined. Logistic regression analysis was also carried out to identify the extent to which airway assessment factors reflected difficult intubation. RESULTS: As aging, head and neck movement, thyromental distance, and interincisor gap decreased, the grade of dentition, Mallampati score, cervical joint rigidity and the ratio of Arne score > 11 increased. In the old and middle group, the incidence of difficult intubation was increased compared with the young group. Dentition in the young group, Mallampati score and interinsisor gap in the middle group and Mallampati score, cervical joint rigidity in the old group respectively predicted difficult intubation. CONCLUSIONS: Compared to young individuals, middle-aged or elderly adults are likely to experience more difficulty in endotracheal intubation and its predictive factors could vary by age group.

Effects of pneumoperitoneal pressure and position changes on respiratory mechanics during laparoscopic colectomy / 대한마취과학회지

BACKGROUND: This study was designed to assess the effects of pneumoperitoneal pressure (PP) and positional changes on the respiratory mechanics during laparoscopy assisted colectomy. METHODS: Peak inspiratory pressure, plateau pressure, lung compliance, and airway resistance were recorded in PP of 10 mmHg and 15 mmHg, with the position change in 5 steps: head-down at 20degrees, head-down at 10degrees, neutral position, head-up at 10degrees and head-up at 20degrees. RESULTS: When the patient was placed head-down, the position change accentuated the effects of pneumoperitoneum on respiratory mechanics. However, when the patient was placed in a head-up position during pneumoperitoneum the results showed no pattern. In the 20degrees head-up position with the PP being 10 mmHg, the compliance increased from 30.6 to 32.6 ml/cmH2O compared with neutral position (P = 0.002). However with the PP being 15 mmHg, the compliance had not changed compared with neutral position (P = 0.989). In 20degrees head-down position with the PP of 10 mmHg, the compliance was measured as 24.2 ml/cmH2O. This was higher than that for patients in the 10degrees head-down position with a PP of 15 mmHg, which was recorded as 21.2 ml/cmH2O. Also in the airway resistance, the patient in the 20degrees head-down position with the PP of 10 mmHg showed 15.8 cmH2O/L/sec, while the patient in the 10degrees head-down position with the PP of 15 mmHg showed 16.2 cmH2O/L/sec of airway resistance. These results were not statistically significant but still suggested that the head-down position accentuated the effects of pneumoperitoneum on respiratory mechanics. CONCLUSIONS: Our results suggest that respiratory mechanics are affected by the patient position and the level of PP - the latter having greater effect.

Fluoroscope guided epidural needle insertioin in midthoracic region: clinical evaluation of Nagaro's method / 대한마취과학회지

BACKGROUND: In the midthoracic region, a fluroscope guided epidural block has been proposed by using a pedicle as a landmark to show the height of the interlaminar space (Nagaro's method). However, clinical implication of this method was not fully evaluated. We studied the clinical usefulness of a fluoroscope guided thoracic epidural block in the midthoracic region. METHODS: Twenty four patients were scheduled to receive an epidural block at the T6-7 intervertebral space. The patients were placed in the prone position. The needle entry point was located at the junction between midline of the pedicle paralleled to the midline of the T7 vertebral body (VB) and the lower border of T7 VB on anteroposterior view of the fluoroscope. The needle touched and walked up the lamina, and the interlaminar space (ILS) was sought near the midline of the VB at the height of the pedicle. RESULTS: The authors could not insert an epidural needle at T6-7 ILS in two patients and it was instead inserted at T5-6 ILS. However, other patients showed easy insertion at T6-7 ILS. The mean inward and upward angulations were 25degrees and 55degrees respectively. The mean actual depth and calculated depth from skin to thoracic epidural space were 5.1 cm and 6.1 cm respectively. Significant correlation between actual needle depth and body weight, podendal index (kg/m) or calculated needle depth was noted. CONCLUSIONS: The fluorposcope guided epidural block by Nagaro's method was useful in the midthoracic region. However, further study for the caudal shift of needle entry point may be needed.

A comparison of hemodynamic changes after endotracheal intubation by the Optiscope(TM) and the conventional laryngoscope / 대한마취과학회지

BACKGROUND: Optiscope(TM) is a newly developed video stylet device. This study evaluated and compared the hemodynamic changes observed after endotracheal intubation with video stylet and after conventional laryngoscopic endotracheal intubation. METHODS: Fifty-eight adult patients with American Society of Anesthesiologists (ASA) physical status class 1 or 2, undergoing general anesthesia, were randomized into two groups: one group of patients were intubated using video stylet (n = 29) and the other group were intubated using direct laryngoscope (n = 29). Systolic blood pressure (SBP), mean arterial pressure (MAP), diastolic blood pressure (DBP), heart rate (HR), POGO (percentage of glottic opening) score, time for intubation and degree of sore throat were recorded. RESULTS: There were no significant differences in the SBP, MAP, DBP, HR, and the sore throat incidence between the two groups. Optiscope(TM) produced better POGO scores, but time for intubation was longer than with conventional laryngoscope. CONCLUSIONS: Optiscope(TM), when compared with conventional laryngoscope for intubation, does not modify the hemodynamic response, but it provides a better view of the vocal cords.

Seizure developed after palonosetron intravenous injection during recovery from general anesthesia: A case report / 대한마취과학회지

Seizure associated with antiemetics is rare. We report seizure associated with a 5-HT3 receptor antagonist in a 38 years old female. The patient underwent ureterorenoscopic lithotripsy due to left upper ureter stone. After operation, the patient complained of nausea in the postanesthetic recovery unit. In order to subside symptom, the patient was administrated 5-HT3 receptor antagonist, palonosetron, 0.075 mg intravenously. Shortly after administration of that, the patient developed generalized tonic-clonic seizures. The symptom was subsided after midazolam and thiopental sodium were injected. But 40 minutes later, seizure recurred and subsided with midazolam again. The patient recovered completely without any specific sequelae.

The antiemetic effect of midazolam or/and ondansetron added to intravenous patient controlled analgesia in patients of pelviscopic surgery / 대한마취과학회지

BACKGROUND: We made a comparative study on the antiemetic effect of midazolam and ondansetron added to intravenous patient-controlled analgesia (PCA) using fentanyl with gynecologic patients undergoing pelviscopic surgery. METHODS: The PCA using 20 microg/kg of fentanyl was started in all groups postoperatively. A dose of 16 mg of ondansetron was added to the PCA of group O (n = 30). A dose of 5 mg of midazolam was added to the PCA of group M (n = 30). While 16 mg of ondansetron and 5 mg of midazolam were added to the PCA of group MO (n = 30). Total volume of the PCA was 60 ml, and the PCA system was programmed to deliver 0.5 ml/h of continuous doses and a 0.5 ml bolus on demand, with a 15 minutes lockout interval. The incidence of postoperative nausea and vomiting (PONV), sedation score, visual analog scale (VAS) for pain, and rescue drug dose for PONV were investigated at the postanesthesia care unit (PACU), 6 hours, and 24 hours after recovery. RESULTS: The incidence of PONV in group MO was significantly lower than in group O at PACU, 24 hours after recovery (P < 0.05). The sedation score and VAS pain score showed no differences among all groups. CONCLUSIONS: Midazolam added to PCA using fentanyl proved more effective than ondansetron in preventing PONV without adverse effects.

Distance from the lumbar epidural space to the skin in Korean adults

BACKGROUND: Lumbar epidural block is a common regional anesthetic/analgesic technique. The depth of the epidural space beneath the skin surface varies from patient to patient at the same vertebral level. It also varies at different levels of the spinal column in the same patient. This study was performed to evaluate the correlations between the lumbar epidural depth and physical measurements depending on the puncture site. METHODS: Data was gathered from 1,653 patients who were undergoing elective lumbar epidural blocks for anesthesia during surgical procedures. The age, gender, height and weight were obtained from the medical records. We calculated the physical parameters such as the weight/height ratio, the body mass index (BMI) and Broca's index. Pearson's correlation analysis and regression testing between the lumbar epidural depth and the physical measurements were performed. RESULTS: The epidural depths at the L2-3, L3-4, L4-5 and L5-S1 intervertebral space were 4.4 +/- 0.62, 4.6 +/- 0.69, 4.6 +/- 0.69 and 4.1 +/- 0.52 cm, respectively. A significant correlation was found between the epidural depth and the weight/height ratio and BMI. CONCLUSIONS: The weight/height ratio and BMI showed the highest correlation with the lumbar epidural depth.

Optimal dose of fentanyl for the prevention of emergence agitation after desflurane anesthesia in children undergoing tonsillectomy

BACKGROUND: Emergence agitation frequently occurs after desflurane anesthesia in children. We designed this study to find the optimal dose of fentanyl for the prevention of emergence agitation after desflurane anesthesia in children for tonsillectomy. METHODS: Eighty-one patients (3-10 yr) receiving desflurane anesthesia for tonsillectomy was randomly allocated to one of 3 groups. Fentanyl 1 microg/kg (group 1, n = 26), 2 microg/kg (group 2, n = 27), 3 microg/kg (group 3, n = 28) was administered intravenously just before inducing anesthesia. Anesthesia was maintained with desflurane. The recovery characteristics, such as the time to first movement, extubation and discharge from the recovery room were assessed. And patients reported their frequency of emergence agitation and severity of postoperative pain at recovery room. RESULTS: There were no significant differences between the three groups regarding the time to extubation and discharge from the recovery room. The incidence of emergence agitation was 42% in group 1, 25% in group 2, 10% in group 3 and that was significantly lower in group 3 than in group 1 (P < 0.05). The incidence of severe pain was lower in group 3 than in group 1 and group 2 (P < 0.05). CONCLUSIONS: In children undergoing tonsillectomy with desflurane anesthesia, 2 microg/kg and 3 microg/kg of fentanyl given just before induction had a reduced incidence of emergence agitation without a delay in recovery.

Pneumomediastinum and pneumothorax after orthognathic surgery: A case report / 대한마취과학회지

The occurrences of pneumomediastinum and pneumothorax after oral and/or maxillofacial surgery are rare, but both are potentially life-threatening complications. Most of the cases that present pneumomediastinum and pneumothorax in the oral and/or maxillofacial surgery result from air dissecting down the fascial planes of the neck. We report a case of a 23-year-old male patient who underwent bilateral sagittal split ramus osteotomy under general anesthesia and developed pneumomediastinum and pneumothorax without any traumatic introduction of air through the cervical fascia three days postoperatively. The possible causes and its prevention are discussed with a review of the relevant literature.

The clinical effectiveness of the streamlined liner of pharyngeal airway (SLIPA(TM)) compared with the laryngeal mask airway ProSeal(TM) during general anesthesia / 대한마취과학회지

BACKGROUND: The aim of this study was to compare the streamlined liner of the pharynx airway (SLIPA), a new supraglottic airway device (SGA), with the laryngeal mask airway ProSeal(TM) (PLMA) during general anesthesia. METHODS: Sixty patients were randomly allocated to two groups; a PLMA group (n = 30) or a SLIPA group (n = 30). Ease of use, first insertion success rate, hemodynamic responses to insertion, ventilatory efficiency and positioning confirmed by fiberoptic bronchoscopy were assessed. Lung mechanics data were collected with side stream spirometry at 10 minutes after insertion. We also compared the incidence of blood stain, incidence and severity of postoperative sore throat and other complications. RESULTS: First attempt success rates were 93.3% and 73.3%, and mean insertion time was 7.3 sec and 10.5 sec in PLMA and SLIPA. There was a significant rise in all of hemodynamic response from the pre-insertion value at one minute following insertion of SLIPA. But, insertion of PLMA was no significant rise in hemodynamic response. There was no statistically significant difference in the mean maximum sealing pressure, gas leakage, lung mechanics data, gastric distension, postoperative sore throat and other complication between the two groups. Blood stain were noted on the surface of the device in 40% (n = 12) in the SLIPA vs. 6.7% (n = 2) in the PLMA. CONCLUSIONS: The SLIPA is a useful alternative to the PLMA and have comparable efficacy and complication rates. If we acquire the skill to use, SLIPA may be considered as primary SGA devices during surgery under general anesthesia.

The effects of continuous infusion of ondansetron on postoperative nausea and vomiting in patients receiving IV-patient controlled analgesia following gynecological surgery / 대한마취과학회지

BACKGROUND: This study was designed to evaluate the effects of continuous infusion of ondansetron on postoperative nausea and vomiting (PONV) in patients receiving intravenous patient controlled analgesia (IV-PCA) following laparoscopic gynecological surgery. METHODS: Sixty ASA class I and II patients scheduled for gynecological laparoscopic surgery were randomly divided into the following 3 groups that received the specified dosages of ondansetron mixed with IV-PCA: placebo (group 1), ondansetron 8 mg (group 2), ondansetron 16 mg (group 3). The incidences of nausea, vomiting, visual analogue scale (VAS), and side effects were then recorded in the recovery room, 24 h, 48 h and 72 h postoperatively. RESULTS: There were no significant differences in the occurrence of nausea between group 1 and 2. However, the incidence of nausea in group 3 was significantly lower than in group 1 at 24 h and 48 h after surgery. In addition, significant differences in the occurrence of vomiting were observed among the three groups. However, with the exception of pruritus, no side effects were observed in any of the groups. CONCLUSIONS: IV-PCA mixed with 16 mg of ondansetron effectively prevented nausea at 24 h and 48 h after gynecologic laparoscopic surgery.

The Effects of Remifentanil on Hemodynamic Changes in Endotracheal Intubation during Rapid Sequence Induction using Thiopental-succinylcholine or Propofol-succinylcholine / 대한마취과학회지

BACKGROUND: This study evaluated the effects of remifentanil on hemodynamic changes in endotracheal intubation during rapid sequence induction using thiopental or propofol and succinylcholine. METHODS: One hundred and twenty patients were divided into 4 groups (30 patients in each group).Anesthesia was induced with propofol 2 mg/kg or thiopental 5 mg/kg and succinylcholine 1 mg/kg followed by remifetanil 0.5microgram/kg (group PR), remifentanil 1microgram/kg (group TR) or normal saline as control (group PC, group TC).An endotracheal intubation was performed 90 s later, and vecuronium 0.08 mg/kg was given for neuromuscular block.Anesthesia was maintained using 1-3 vol% enflurane with 2 L/min N2O and 2 L/min O2.Arterial blood pressure (ABP) and heart rate (HR) were recorded before induction, just before intubation, and at 1 min intervals for 5 min after intubation.The incidence of hypertension, hypotension, tachycardia, and bradycardia were recorded. RESULTS: ABP in group PR was lower than in group TR, but HR was not different.The incidence of hypotension in group PR was higher than group TR or group PC.ABP in groups using remifentanil was lower than in control groups.The incidence of hypertension and tachycardia in groups using remifentanil were lower than control groups. CONCLUSIONS: During administration of propofol or thiopental and succinylcholine, remifentanil as a bolus for rapid sequence induction attenuated cardiovascular responses to endotracheal intubation effectively, but with a higher incidence of hypotension following propofol.

Comparison between Remifentanil and Nicardipine with Esmolol Continuously Infused for Attenuation of Hemodynamic Changes during Total Knee Arthroplasty in Elderly Patient / 대한마취과학회지

BACKGROUND: The use of tourniquet is associated with severe hemodynamic changes, particularly in elderly patients. This study examined the effects of continuously infused remifentanil or nicardipine with esmolol on the attenuation of the hemodynamic changes with enflurane inhalation during total knee arthroplasty in elderly patients. METHODS: Thirty elderly female patients undergoing total knee arthroplasty were enrolled into this randomized, prospective study. Remifentanil (group R) or nicardipine with esmolol (group EN) was infused using a titration method to maintain a mean arterial pressure (MAP) of 90 mmHg to 70 mmHg during tourniquet inflation. In addition, the inhalation of enflurane was adjusted to guarantee a hypnotic state based on entropy. The hemodynamic variables, inhaled concentration of enflurane, recovery time, and postoperative pain characteristics were measured and compared. RESULTS: Following tourniquet inflation, the MAP was increased and maintained in the target since 20 min after that in both group. Following tourniquet deflation the MAP was decreased significantly in both groups and more patients in group R required a vasopressor. Group R inhaled a lower enflurane concentration and showed more rapid recovery than group EN. There were no significant differences in the level of postoperative pain between the two groups. CONCLUSIONS: These results suggest that remifentanil is more likely to be associated with hypotension after tourniquet deflation and require more attention than nicardipine with esmolol.

The Effect of Minocycline on Allodynia Produced by Repeated Injection of Low pH Saline in Rats / 대한마취과학회지

BACKGROUND: Activation of glial cells (microglia and astroglia) has been observed in rat neuropathic pain models and they are known to play a role in inducing allodynia in these animals. Minocycline (MC), a tetracycline derivative antibiotics, displays selective inhibition of microglial activation. The author investigated antinociceptive effect of intrathecal administration of MC on muscular pain model induced by repetitive intramuscular injection of low pH saline. METHODS: pH 5 saline was injected into gastrocnemius muscle of rat. Second injection of pH 5 saline was done 3 days after first injection. To study preventive effect of MC, normal saline or MC 50microgram or 100microgram was administered intrathecally 15 min before each low pH saline injection. To evaluate the therapeutic effect, normal saline or MC 500microgram was administered intrathecally after pain model made. To quantify the mechanical allodynia, withdrawal threshold to mechanical stimuli was measured using von Frey filament. RESULTS: Preventive administration of MC 50microgram did not attenuate the mechanical allodynia, on the contrary MC 100microgram administration showed pain attenuation. Therapeutic administration of MC 500microgram did not show analgesic effect. CONCLUSIONS: Preventive intrathecal administration of MC 100microgram attenuated mechanical allodynia, but not in preventive MC 50microgram and therapeutic administration.

The Effect of Remifentanil, Alfentanil, and Fentanyl on the Hemodynamic Changes, Analgesia, and Sedation during Retrobulbar Block in Cataract Surgery / 대한마취과학회지

BACKGROUND: This study was designed to compare the effects of remifentanil, alfentanil, and fentanyl on the hemodynamic changes, sedation, and analgesia when administered with small doses of midazolam in patients undergoing a retrobulbar block for cataract surgery. METHODS: Sixty patients scheduled for cataract surgery were divided into 4 groups (n = 15 for each group). Firstly, group C received 5 ml of a normal saline solution, 3 min before a retrobulbar block. Next, group R received remifentanil 0.3g/kg. Furthermore, group A received a 4.5g/kg dose of alfentanil, 90 s before a retrobulbar block, and group F received fentanyl 0.6g/kg, 210 s before a retrobulbar block. All solutions were mixed with normal saline to a 5 ml volume. In group R, A, and F, midazolam (0.5 mg for patients over the age of 65 years; 1.0 mg in patients under the age of 65 years) was injected 3 min before the retrobulbar block. RESULTS: The systolic blood pressure in patients significantly increased at 1 or 2 minutes after a retrobulbar block in group C and at 1 minute in group F. For group R, the systolic blood pressure decreased significantly at 3, 4, 5, and 10 minutes, and at 2, 3, 4, 5, and 10 minute in group A. The mean OAA/S scale during a retrobulbar block significantly declined in groups R and A. The VAS score for pain was significantly lower in groups R and A, whereas the VAS anxiety index was significantly lower in groups R, A, F compared to group C (P 0.05). CONCLUSIONS: We found that the combination of remifentanil or alfentanil with midazolam showed better hemodynamic stability, sedative, and analgesic effects compared to fentanyl with midazolam in the retrobulbar block for cataract surgery.

The Effect of Cuff Pressure of Laryngeal Tube on Postoperative Sore Throat after General Anesthesia Using N2O / 대한마취과학회지

BACKGROUND: The cuff pressure (CP) of the laryngeal tube airway (LTA) increases during general anesthesia using nitrous oxide. However, there have been few studies on the relationship between CP and postoperative sore throat (POST). This study evaluated the efficacy of the CP on a POST on the recovery time and postoperative day. METHODS: Forty patients were divided into two groups, group M (n = 20) and group I (n = 20). In all patients, the CP was set to 65 cmH2O at the induction of anesthesia. In group M, the CP was maintained at 60-70 cmH2O during general anesthesia using N2O. However, in group I, the CP was allowed to increase. The CP was measured every 10 minutes during surgery in the two groups. The frequency and intensity (numerical rating scale of 0-100, NRS-101) of the sore throat was measured at recovery room (RR) and on postoperative day 1 (POD1). RESULTS: There was a significant increase in the CP in group I during general anesthesia and the CP was higher in group I than in group M (P < 0.05). The frequency of POST was higher in group I at RR (10% vs 70%) and POD1 (0% vs 35%) than in group M. In addition, the NRS-101 was higher in group I at RR and POD1 than in group M (P < 0.05). CONCLUSIONS: The CP of the LTA needs to be monitored and controlled during surgery in order to reduce POST.