Changes of Lung Compliance with Oxygen Toxicity in Rat / 대한마취과학회지

Oxygen therapy is clear benefit in the treatment of tissue hypoxia, but high concentrations and long term exposures of oxygen carry the risks of detrimental physiologic changes and tissue damages. Tissue damages involve decreased surfactant production,alveolar edema, and alveolar hemorrhage. In spite of these damage, diagnosis of oxygen toxicity is difficult in many clinical settings. In this study, we measured lung compliance to evaluate the oxygen toxicity in 60 white rat of 100-150 g body weight Rats were divided into 6 groups. Group I was control graup, exposed to room air, group II -group V were exposed to 100% oxygen, group II for 24 hours, group IlI for 48 hous, group IV for 72 hours, and group V for 96 hours. Group VI was exposed to oxygen in serial as 30% oxygen for 24 hours, 60% oxygen for 24 hours and then 100% oxygen for 96 hours. After oxygen exposure we obseved changes of lung compliance and pathologic findings, compliance of group V was 15.94 mL/cmH2O significantly lower than that of eontrol group (p<0.05) and lung weight of group V was 2.16 g/100 g heavier than the other groups (p<0.05). Although we found oxygen tolerance was developed in group V, we could not differentiate the degree of pathologic damage cauesd from oxygen toxicity by pathologic findings. We concluded that the measurement of lung compliance is valuable in diagnosis of oxygen toxicity and thus in reducing lung damages.

Changes of Lung Compliance with Oxygen Toxicity in Rat / 대한마취과학회지

Oxygen therapy is clear benefit in the treatment of tissue hypoxia, but high concentrations and long term exposures of oxygen carry the risks of detrimental physiologic changes and tissue damages. Tissue damages involve decreased surfactant production,alveolar edema, and alveolar hemorrhage. In spite of these damage, diagnosis of oxygen toxicity is difficult in many clinical settings. In this study, we measured lung compliance to evaluate the oxygen toxicity in 60 white rat of 100-150 g body weight Rats were divided into 6 groups. Group I was control graup, exposed to room air, group II -group V were exposed to 100% oxygen, group II for 24 hours, group IlI for 48 hous, group IV for 72 hours, and group V for 96 hours. Group VI was exposed to oxygen in serial as 30% oxygen for 24 hours, 60% oxygen for 24 hours and then 100% oxygen for 96 hours. After oxygen exposure we obseved changes of lung compliance and pathologic findings, compliance of group V was 15.94 mL/cmH2O significantly lower than that of eontrol group (p<0.05) and lung weight of group V was 2.16 g/100 g heavier than the other groups (p<0.05). Although we found oxygen tolerance was developed in group V, we could not differentiate the degree of pathologic damage cauesd from oxygen toxicity by pathologic findings. We concluded that the measurement of lung compliance is valuable in diagnosis of oxygen toxicity and thus in reducing lung damages.

The Effects of Physostigmine on Arousal after Laryngomicroscopic surgery / 대한마취과학회지

Physostigmine has been used to counteract somnolence or coma induced by different types of phamacological agent, such as anticholinergics, opioids, ketamine and tricyclic antidepressants. In this study, we have assesed the effects of physostigmine on arousal after laryngomicroscopic surgery under enflurane-N2O general anesthesia and the effects of muscle relaxants. Forty patients were divided randomly into four groups such as I (succinylcholine only), II (vecuronium only), III(succinylcholine and physostigmine) and IV(vecuronium and physostigmine). Physostigmine 1mg was administered intravenously at the end of operation. We evaluated the recovery time of spontaneous respiration, gag reflex, pain response, extubation, eye opening on command and orientation after the end of operation. We also observed the end tidal CO2 and expired enflurane concentration with SARA(R) spectrometry at the end of operation and at the time of each recovery parameters returned . Our results revealed that physostigmine groups(group III and IV) were recovered more rapidly in the recovery time of eye opening to verbal command and orientation than non-physostigmine groups(group I and II ). But there was no difference in recovery time of spontaneous respiration, gag reflex, pain response and extubation. Therefore, we concluded that physostigmine 1 mg, i.v. has the effects of early arousal after short and deep general anesthesia and it did not show any specific complications such as bradycardia, bronchospasm, nausea and vomiting.

Epidural morphine on ventilatory function in chest trauma and thoracotomy patients

Epidural morphine injection was done in nineteen patients who had been admitted from March to August 1990 to the Intensive Care Unit, Severance Hospital, Yonsei Medical Center for respiratory care including ventilator care. Morphine suplphate, 2.67 +/- 0.27 mg was injected one to three times to four patients after chest trauma, and to fifteen patients after thoracotomy. Tidal volume and vital capacity were increased from 4.45 +/- 0.48 and 8.31 +/- 0.50 to 6.91 +/- 0.41 and 12.81 +/- 0.73 mg/kg. However, respiratory rates decreased from 26.07 +/- 1.41 to 20.07 +/- 1.16/min. Inspiratory force increased from -13.40 +/- 1.31 to -26.53 +/- 1.82 cmH2O. Pain score decreased from 9.22 +/- 0.57 to 3.56 +/- 0.83 during this period. PaCO2 did not differ significantly (39.33 +/- 1.13 and 39.48 +/- 1.42 mmHg). Side effects such as pruritis and urinary retention were treated with naloxone 7 approximately 10 ng/kg/min. Mean arterial pressure and pulse rates stayed stable during the study periods. Ventilator hours and ICU stays differed from the control group. However, the duration was not statistically significant. The control group consisted of patients who were admitted during the six months from September 1989 to February 1990 to the ICU for respiratory care, without epidural morphine injection.

In Vivo Assessment of Percutaneous Anesthetic Patch ( 4 % Tetracaine Cream ) / 대한마취과학회지

Application of percutaneous local anesthesia for painfree venepuncture has been studied for more than 30 years. Practically, Eutectic Mixture of Local Anesthetics (EMLA) has been available in clinical fields, and current studies suggest that 4% tetracaine would appear to have a more rapid onset, greater potency and longer duration than EMLA. This study was designed to assess the anesthetic effect of 4% tetracaine cream with a carbomer and a methylcellulose base. We studied onset time and two bases were compared with respect to pain score and allergic reactions of the skin. 4% tetracaine cream produced significant anesthesia after a 35-45 min. application and statistical analysis indicated that the carbomer base produced a more effective percutaneous local anesthesia to pin-prick test than the methylcellulose base. But there were no significant differences in allergic reactions. Therefore, 4% tetracaine cream can be applied to the skin without discomfort and alleviates pain from the needle puncture, especially in children.