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B Jawan

Publications and source records attributed to B Jawan.

At least 73 records · Page 4Linked to original sources
PubMed1997

Unsuspected difficult intubation caused by a laryngeal web.

We report a case of unsuspected difficult intubation in an adult caused by laryngeal web formation in the anterior commissure of the larynx. After induction of anaesthesia, most parts of the posterior commissure of the vocal cords were seen clearly at laryngoscopy, but a 7.5-mm internal diameter (id) tracheal tube could not be advanced below the level of the vocal cords because of resistance. Intubation was re-attempted several times after oxygenation by mask with trials of smaller tubes. Finally, a 5.0-mm id cuffed tube was passed successfully through the vocal cords, and secured in place. Because of the unexpected difficulties in intubation, an otolaryngologist was consulted to examine the larynx with a microscope. A web of 0.5 cm in the anterior commissures was found which caused subglottic stenosis.

Aged↗
PubMed1997

Comparison of sevoflurane with halothane in pediatric ambulatory anesthesia: an experience in Taiwan.

BACKGROUND: Sevoflurane, with blood/gas partition coefficient of 0.69 and MAC of 1.76 is a fast acting, potent inhalation anesthetic. Its suitability and safety for pediatric ambulatory anesthesia were assessed and compared with that of halothane. METHODS: Thirty two unpremedicated pediatric patients undergoing elective herniorrhaphy on day-surgery basis were randomly allocated to 2 groups of equal number to receive either sevoflurane or halothane anesthesia. Employing mask technique, anesthesia was induced with 60% nitrous oxide and 3 MAC of either sevoflurane or halothane in oxygen. Anesthesia was maintained respectively with 1-1.5 MAC of sevoflurane or halothane. The induction time, emergence time and untoward effects during anesthesia were analyzed and compared. RESULTS: It was shown that both the induction time and emergence time were significantly shorter in patients receiving sevoflurane. None had major complications. CONCLUSIONS: The results strongly suggest that sevoflurane is preferable to halothane for pediatric ambulatory anesthesia.

Ambulatory Surgical Procedures↗
PubMed1997

Pulmonary edema complicated by post-extubation laryngospasm: a case report.

A case of post-extubation laryngospasm complicated by negative pressure pulmonary edema in a 26 year-old healthy male undergoing right herniorrhaphy is presented. Immediately after extubation laryngeal stridor was noted, which rapidly developed in severe laryngospasm. Two minutes after the laryngospasm, reintubation was accomplished, but pulmonary edema was soon noted. After supportive treatment his condition improved and the endotracheal tube was removed in the next day. The patient was discharged home uneventfully on the 4th postoperative day. The cause, mechanism, treatment and how to prevent such complications are discussed.

Adult↗
PubMed1996

Aspiration in transtracheal jet ventilation.

BACKGROUND: Transtracheal jet ventilation (TJV) has been used successfully for managing difficult airways. However, there are some controversies regarding pulmonary aspiration. It has been shown that TJV caused no aspiration as long as the frequency of ventilation was kept higher than 60/ min. On the other hand, it has been demonstrated that manual translaryngeal jet ventilation at 20 breaths per minute also provided good protection from aspiration even with 30-degree head-up position. The purpose of this study was to reevaluate this controversy with observation of the trachea and the lungs together during TJV. METHODS: Eight mongrel dogs were anesthetized, paralyzed and ventilated transtracheally with jet ventilator at frequencies variying from 600 to 10/min. The airway pressures below and above the jetting port were measured. The mouth of the dog was then filled with barium and chest x-rays were taken 5 minutes after each different jetting frequency. RESULTS: No tracheal or pulmonary aspiration was observed on chest x-rays as long as the frequencies were set above 80 per minute. With frequencies of 60 per minute, barium was seen in the trachea but at a level above the jetting port. Slowing down the frequency to 10/min did not affect the level of barium. CONCLUSION: No aspiration could be visualized on chest x-rays. The mechanism for preventing pulmonary aspiration is thought to be due to forceful continuous gas outflow through the larynx. The epiglottis seems to play no role in this mechanism. The limited tracheal aspiration was probably due to the existence of a negative pressure in the upper airway. Cessation of the TJV will cause a drop in this pressure gradient and results in pulmonary aspiration. It is recommended that the airway above the jetting port be totally cleansed prior to discontinuation of the tanstracheal jet ventilation.

Animals↗
PubMed1996

The comparative potency of intravenous nicardipine and verapamil on the cardiovascular response to tracheal intubation.

BACKGROUND: Two different types of calcium channel blockers (namely nicardipine and verapamil) have been used widely in clinical practice. However, no clinical studies have previously been performed to ascertain the relative potency of intravenous verapamil and nicardipine in the attenuation of cardiovascular response to tracheal intubation. METHODS: We assessed the optimal dose and relative potency of verapamil and nicardipine in the attenuation of hemodynamic response to tracheal intubation in 135 healthy patients. Control group (Group D received normal saline i.v. Patients in Groups II-V received nicardipine 0.005, 0.01, 0.03 and 0.06 mg/kg i.v., respectively. Patients in Groups VI-IX received verapamil 0.03, 0.05, 0.1 and 0.15 mg/kg i.v., respectively. Anaesthesia was induced with propofol (2.5 mg/kg) and muscle relaxation was facilitated by vecuronium (0.2 mg/kg, i.v.). One min after induction, tracheal intubation was performed. Mean arterial pressure (MAP) was measured at 1 min interval from 10 min before induction to 15 min after induction. RESULTS: The ED50 with 95% confidence interval of nicardipine and verapamil for the attenuation of 50% mean arterial pressure (MAP) increase after tracheal intubation were 14.55 micrograms/kg (8.25-25.67) and 75.4 micrograms/kg (58.7-96.95), respectively. The ED50 with 95% confidence interval of verapamil for the reduction of the 50% heart rate (HR) increase post tracheal intubation was 57.4 micrograms/kg (18-182.2). No differences were found in the frequency of perioperative arrhythmia, post-operative hypotension, postoperative emesis, dizziness, muscle weakness and muscle soreness within two hours following surgery, when compared control with experimental groups (p > 0.05). CONCLUSIONS: These results suggest that verapamil and nicardipine attenuate the hypertensive response to tracheal intubation without significant adverse effects in healthy patients. The dose ratio (ED50 nicardipine and ED50 verapamil for MAP) with 95% confidence interval was revealed to be 2.3 (1.82-7.41).

Adult↗
PubMed1995

Effects of temperature on somatosensory evoked potentials during open heart surgery.

Somatosensory evoked potentials (SEPs) have been found to be useful for early detection of brain ischemia during hypothermic cardiopulmonary bypass in cardiac surgery. However, the relationship between temperature and latency period remains unclear. We prospectively analyzed SEPs obtained during hypothermic cardiopulmonary bypass in 20 patients who had valvular replacement. We concluded that i) a linear correlation was found between temperature and latency period during cooling and rewarming, ii) no hysteresis effect existed in cooling and rewarming, iii) there was a greater hypothermic effect on the synaptic transmission than on the conduction velocity, and iv) age had also more profound effect on relationship between temperature and latency of SEPs.

Adult↗
PubMed1995

Hypercarbia induced by detachment of inner fresh gas delivery tube of the bain circuit--a case report.

Semi-open system such as Bain circuit is occasionally used in general anesthesia. The system has many advantages such as use of a single, light weight tube which is adaptable to both adult and pediatric patients and bypass of the carbon dioxide absorber. It is especially useful in procedures on the head, face and neck. The main disadvantage of Bain circuit is the difficulty in testing the inner tube. We encountered a case of hypercarbia due to detachment of the inner fresh gas delivery tube of the Bain circuit. The whole outer tube became a dead space and as a consequence, hypercapnia was unavoidable due to the "to and fro" mechanism of rebreathing. Adequate gas flow and manual hyperventilation would not correct the situation. After changing the tube CO2 tension gradually returned to normal. Many methods for testing of the Bain circuit have been published. Pethick technique, Foëx and Crampton Smith test and test adaptor are useful. Hypercarbia is difficult to detect under general anesthesia. It is often misdiagnosed due to its similarity to other stress responses. Therefore, it is necessary to check ABG's in patients with unexplained tachycardia and/or in those who fight the ventilator even with sufficient amount of muscle relaxant. For quality assurance, use of capnography is recommended for routine use in anesthesia.

Anesthesia, General↗
PubMed1995

Use of a single lumen endotracheal tube and continuous CO2 insufflation in transthoracic endoscopic sympathectomy.

BACKGROUND: Transthoracic endoscopic sympathectomy (TES) is an accepted standard surgical treatment for palmar hyperhidrosis. For anesthetic management, a double lumen endobronchial tube is usually used to deflate the lung on the operative side. Recently we have applied continuous insufflation of carbon dioxide (CO2) into the pleural cavity to merely compress one lung while ventilating both lungs with a conventional single lumen endotracheal tube. METHODS: We have studied 45 patients (ASA I and II) who underwent bilateral TES, Thirty-three were ventilated by single lumen tube and the other 12 by double lumen endobronchial tube with one lung ventilation. In both groups I and II, CO2 was insufflated slowly through the scope to a intrapleural pressure of 20 cm H2O. Both lungs were ventilated with peak pressure of less than 20 cmH2O at tidal volume of 5-12 ml/kg at 10-16 beats/min. RESULTS: In these patients, no CO2 retention was noted. Oxygenation and cardiovascular stability were maintained and there were no complications. In the double lumen series, we found that oxygen saturation was less uniform and less stable than those in the single lumen series. CONCLUSIONS: It is concluded that the use of single lumen endotracheal tube with continuous insufflation of CO2 in TES is easy, simple and safe.

Adolescent↗
PubMed1994

Comparison of the incidence of postpartum low back pain in natural childbirth and cesarean section with spinal anesthesia.

BACKGROUND: Many parturients and their obstetricians believe that spinal anesthesia will cause low back pain (LBP). MATERIALS & METHODS: We studied prospectively a total of 160 parturients; 80 of them had cesarean section (CS) with spinal anesthesia and another 80 who had natural childbirth. Incidence of LBP was investigated and compared in these patients before pregnancy, during pregnancy and postpartum. RESULTS: Our result showed that before pregnancy, about one third (33.1%) of the parturients already had LBP and the incidence of LBP seemed to increase during pregnancy. The incidence of LBP decreased gradually postpartum. There was no difference in the incidence of postpartum LBP between the CS with spinal anesthesia group and the natural childbirth group. CONCLUSIONS: We concluded that postpartum LBP could be related to changes during pregnancy and not related to spinal anesthesia.

Adult↗