Estimation of the proper length of nasotracheal intubation by Chula formula.

OBJECTIVES: To assess whether Chula formula can predict the proper length of nasotracheal intubation. MATERIAL AND METHOD: This was a prospective study of 100 patients (50 males and 50 females) who underwent general anesthesia with nasotracheal intubation (number 8.0 for male and 7.0 for female) between December 2005 and March 2007. The Chula formula was used to calculate the length of endotracheal tube (ETT) at the right external naris = 9 + (body height/10) cm. After intubation, a fiberoptic bronchoscope was inserted into the ETT to measure the distance from the tip of ETT to the carina and the distance from the upper border of the cuff of ETT to the vocal cords. RESULTS: The mean length of nasotracheal tube at the right external naris calculated by Chula formula was 25.4 cm in males and 24.4 cm in females. The mean distance from the tip of ETT to the carina was 3.9 cm in males and 3.1 cm in females. The mean distance from the upper border of the cuff of ETT to the vocal cords was 2.6 cm in males and 3.0 cm in females. Ninety-three patients with upper border of the cuff of ETT had it placed at least 2 cm below the vocal cords, and in seven patients, the distance from the tip of ETT to the carina was found to be 1 to 1.9 cm. In every patient, it was found that the tip of ETT was placed at least 2 cm cephalad to the carina. CONCLUSION: In the present study, the Chula formula could be used to predict the proper length of nasotracheal intubation in 93 of 100 patients.

Effectiveness of mouthpiece nebulization and nasal swab stick packing for topical anesthesia in awake fiberoptic nasotracheal intubation.

OBJECTIVE: To evaluate the effectiveness of using mouthpiece nebulization and nasal swab stick packing for topical anesthesia in awake fiberoptic nasotracheal intubation. MATERIAL AND METHOD: This was a prospective descriptive study of 30 patients with ASA I-II who underwent elective surgery and suspected of difficult intubation between March 2004 and June 2006. After 2% lidocaine 5 ml was nebulizated in a micronebulizer using oxygen 10 L/min as a driving gas through a standard mouthpiece and 10% cocaine 1 ml on cotton swab-stick was applied to the selected nostril for 15 min, fiberoptic nasotracheal intubation was done while the patient was awake. If the patient had severe gag or cough reflex, 1% lidocaine 5 ml per each time could be injected through the working channel of the fiberoptic bronchoscope. The descriptive statistics were calculated by using SPSS version 11.0. RESULTS: The success rate of awake fiberoptic nasotracheal was 100%. The mean duration of awake fiberoptic nasotracheal intubation was 119.0 +/- 76.8 sec. The responses of the patient to instrumentation during 4 periods, i.e.: passing the endotracheal tube into the nose, passing the bronchoscope into the pharynx-larynx, passing the bronchoscope into the trachea-carina and passing the endotracheal tube into the trachea were, as follows: no response in about 53.3%, 63.3%, 23.3%,and 13.3%; mild pain or reflex in about 46.7%, 10%, 70%, and 86.7%; moderate pain or reflex in about 0%, 3.3%, 6.7%, and 0%; and severe pain or reflex requiring more local anesthetic in about 0%, 23.3%, 0%, and 0%, respectively. Despite complete topical anesthesia in the majority of the patients, two patients required 5 ml more 1% lidocaine and five patients required 10 mL more of the drug through the fiberoptic bronchoscope. There was no serious complication such as hypoxemia, arrhythmia. Twenty-four patients (80%) were satisfied with mouthpiece nebulization and nasal swab packing because they felt safe, did not have pain, and were comfortable; only three patients (10%) were dissatisfied because of numbness of the tongue and difficulty in swallowing; two patients (6.7%) had no comment; and one patient (3.3%) was unable to evaluate due to unplanned tracheostomy. CONCLUSION: In the present study technique of topical anesthesia using 2% lidocaine 5 mL mouthpiece nebulization and 10% cocaine 1 mL soaked nasal swab stick packing is useful and safe for awake fiberoptic nasotracheal intubation in patients with suspected difficult intubation. 76.7% of the patient did not require more local anesthesia and 80% were satisfied with this technique.

Estimation of the proper length of orotracheal intubation by Chula formula.

The ideal proper position of the ETT was indicated when the distance from the tip of ETT to the carina and the distance from the upper border of the cuff of ETT to the vocal cords were found to be at least 2 cm. OBJECTIVE: To assess whether Chula formula can predict the proper length of orotracheal intubation. MATERIAL AND METHOD: This was a prospective study of 100 patients (50 males and 50 females) who underwent general anesthesia with orotracheal intubation. The Chula formula was used to calculate the length of endotracheal tube (ETT) at the right upper canine = 4 + (body height/10) cm. After intubation, a fiberoptic bronchoscope was inserted into the ETT to measure the distance from the tip of ETT to the carina and the distance from the upper border of the cuff of ETT to the vocal cords. RESULTS: The mean length of oratracheal tube at the right upper canine calculated by Chula formula was 20.8 cm in males and 19.6 cm in females. The mean distance from the tip of ETT to the carina was 4.1 cm in males and 3.0 cm in females. The mean distance from the upper border of the cuff of ETT to the vocal cords was 4.5 cm in males and 4.6 cm in females. There were 99 of 100 patients who had the tip of ETT was placed at least 2 cm cephalad to the carina, in only one female patient that the distance from the tip of ETT to the carina was found to be 1.9 cm. In every patient, it was found that the upper border of the cuff of ETT was placed at least 2 cm below the vocal cords. CONCLUSION: In the present study, the Chula formula could be used to predict the proper length of orotracheal intubation in 99 of 100 patients.

Intrathecal fentanyl for prevention of shivering in cesarean section.

OBJECTIVES: The aim of this randomized double-blind study was to investigate whether 20 microg of intrathecally administered fentanyl would influence the incidence and severity of shivering in patients undergoing cesarean section. MATERIAL AND METHOD: Sixty healthy patients scheduled for cesarean section under spinal anesthesia using 2.2 ml of 0.5% hyperbaric bupivacaine with 0.2 ml of morphine 0.2 mg, were randomly allocated to receive an additional 0.4 ml of fentanyl 20 mg intrathecally (Group F) or normal saline 0.4 ml (Group S). RESULTS: The incidence of shivering three hours after spinal anesthesia was 6 of 30 patients, 20% in Group F and 15 of 30 patients, 50% in Group S. The difference was statistically significant (p < 0.05). Almost all of the shivering patients started in their first hour after spinal anesthesia (5 patients in Group F and 13 patients in Group S). None in Group F but 4 patients in Group S started shivering before their babies were delivered. The shivering score was also significantly lower in Group F (p < 0.05). Treatment for shivering was requested in 16% and 26% of the shivering patients in Group F and Group S, respectively. There was no difference in the incidence of pharmacologic side effects. The core temperature did not differ significantly between the groups during 3 hours after spinal anesthesia. CONCLUSION: The addition of 20 microg fentanyl in 2.2 ml of 0.5% hyperbaric bupivacaine with 0.2 ml of morphine 0.2 mg intrathecally can reduce the incidence and severity of intraoperative and postoperative shivering after spinal anesthesia for patients who were receiving cesarean section without increasing other side effects.

Depth of endotracheal tubes in Thai adult patients.

OBJECTIVE: To predict the proper depth of placement of endotracheal tubes, oral and nasal. MATERIAL AND METHOD: This was a prospective study of 100 patients who underwent general anesthesia with oral endotracheal intubation. The cuff of the endotracheal tube was placed 2 cm below the vocal cords. The positions of the endotracheal tube tip and the airway distances of the patients were measured by fiberoptic bronchoscope; OC = the distance from the right upper canine to the vocal cords, NC = the distance from the right external naris to the vocal cords and T = the distance from the vocal cords to the carina. The correlation between the airway distances and patient's factors were analyzed. The proper depth of placement of the endotracheal tube was calculated with the formula OTT = OC + T-2, nasal endotracheal tube NTT = NC + T-2. RESULTS: The mean distance from the endotracheal tube tip to the carina was 3.0 +/- 1.48 cm (ranged 0.7 - 7.5 cm). The distance from the endotracheal tube tip to the carina of 86 from 100 patients was more than 2 cm. The mean OC was 9.79 +/- 1.27 cm. The mean NC was 15.00 +/- 0.84 cm. The mean T were 13.03 +/- 1.48 cm in males and 11.63 +/- 1.25 cm in females and it also related to the height of the person (Pearson correlation = 0.557, p value < 0.05). These distances did not relate to gender. CONCLUSION: The predicted formula of the depth of the endotracheal tube as "Chula formula"; OTT = 4 + (Ht/10) cm (The distance from the right upper canine to the point which is 2 cm above the carina) NTT = 9 + (Ht/10) cm (The distance from the right external naris to the point which is 2 cm above the carina).

Intrathecal fentanyl in spinal anesthesia for appendectomy.

OBJECTIVE: The authors assessed the effectiveness of the administration of fentanyl in spinal anesthesia for appendectomy. MATERIAL AND METHOD: Forty patients randomized double-blind, were recruited to receive either 4 ml of 0.5% hyperbaric bupivacaine + 20 mg of fentanyl (Group F) or 4 ml of 0.5% hyperbaric bupivacaine 0.5% + 0.4 ml normal saline (Group S). RESULTS: There were no significant differences in the highest analgesic level between the groups. The number of segments regressed at 60 min in Group F was statistically less than in Group S (0 vs. 2; P 0.002). Group F showed significantly lower median VNS pain scores than Group S (0 vs. 3; P 0.004). Time to first required postoperative analgesics in Group F was significantly higher than in Group S (13.6 vs. 6.3 h, P < 0.001). The incidence of shivering in Group F was significantly lower than Group S (35% vs. 70%; P 0.023). There were no significant differences in the incidence of nausea, vomiting, hypotension and urinary retention. No patient developed respiratory depression or PDPH. The patients' satisfaction of spinal anesthesia was 100% in Group F and 80% in Group S. CONCLUSION: Intrathecal 20 microg fentanyl significantly improved the quality of analgesia, it prolonged the duration of bupivacaine in spinal anesthesia and delayed the analgesics requirement in the early postoperative period. Shivering was less frequently found in the fentanyl group.

Spinal morphine for post-operative analgesia after lumbar laminectomy with fusion.

BACKGROUND: Intrathecal administration of preservative free morphine (spinal morphine) provides excellent post-operative analgesia. Since the dura is readily accessible by the surgeon during lumbar spinal surgery, it would be convenient and attractive to administer morphine into the spinal space to provide adequate post-operative analgesia in these patients. METHOD: A prospective randomized controlled study evaluated the post-operative analgesic effect of spinal morphine after lumbar laminectomy with fusion. Forty patients were randomly allocated to two groups, morphine (MO) or normal saline (NSS). Morphine 0.3 mg in normal saline 0.3 ml or normal saline 0.3 ml was injected into the dural sac under direct visualization before closing the wound. An intravenous PCA morphine device was provided for post-operative pain relief. RESULTS: Median visual analog scale (VAS) pain scores were lower in the MO group at 2, 4, 24 and 48 h after surgery (1, 1, 2.75 and 1.5 cm in the MO group vs 4.25, 4.25, 5 and 4 cm in the NSS group) (p < 0.05). The time to first patient control analgesia (PCA) demand was delayed in the MO group (131.7 min vs 29.6 min) (p < 0.05). The cumulative doses of PCA morphine consumption were lower in the MO group in the first 24 h and 24-48 h (13.7 and 15.9 mg vs 41.3 mg and 27.1 mg) (p < 0.001). The incidence of pruritus was higher in the MO group in 24 h and 24-48 h (45%, and 45% vs 5% and 10%) (p < 0.05). The incidence and severity of nausea, vomiting and sedation were not different. No patient developed respiratory depression or postdural puncture headache (PDPH). The patients' satisfaction with post-operative pain management was 100 per cent in the MO group and 85 per cent in the NSS group. CONCLUSION: Spinal morphine improved post-operative pain relief after lumbar laminectomy.

Prevention of phantom sensations after spinal anesthesia.

BACKGROUND AND OBJECTIVES: Phantom limb sensation (PLS) after the spinal anesthesia is an unpleasant experience. The occurrence rate was 80 to 83 per cent from previous studies. The purpose of this study is to evaluate the incidence of PLS, comparing between placing the lower limbs in the neutral position when analgesic level reach L1 dermatome (L1 group) and T6 dermatome (T6 group). METHODS: Ninety ASA physical status I-II patients, 19-50 year of age, scheduled for lower abdominal surgery under spinal anesthesia were enrolled. Immediately after the spinal injection, the patients were placed supine with one of lower limbs flexed (both hip and knee) and the other kept straight in the neutral position. The analgesic levels were checked every minute; the flexed limbs were turned to the neutral position when the analgesic level reached L1 and T6, the L1 group and the T6 group respectively. The images of the lower limbs and patients' satisfactions were evaluated 15 minutes after the blockage. RESULTS: Twenty per cent of the patients in the L1 group experienced PLS of the flexed limbs while 82.2 per cent of the patients in the T6 group did (P<0.05). None of the patients in the L1 group felt unsatisfied with PLS, on the other hand, 11.1 per cent of the patients in the T6 group expressed their dissatisfaction and would like to have their limbs extended. CONCLUSIONS: This study revealed that by placing the lower limbs in the neutral position immediately after the spinal injection, before the unwanted positions are memorized, could effectively minimize phantom limb sensation after spinal anesthesia.