• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.500-511
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• 1999

Background: Noninvasive positive pressure ventilation (NPPV) using facial or nasal mask have been widely used for several years in stable patients with chronic neuromuscular disease or central alveolar hypoventilation, and recently have been tried in patients with acute respiratory failure. In a few studies, NPPV was also used to rescue the patients with post-extubation respiratory failure. However, yet it has not been adopted as a weaning method in patients on long-term mechanical ventilation. So we performed this prospective clinical study to evaluate the usefulness of NPPV as a weaning method after removing endotracheal tube intentionally in patients on long-term mechanical ventilation. Method: Twelve patients who had been on invasive mechanical ventilation over 10 days were enrolled and 14 trials of NPPV were done. All had failed at least one weaning trial and showed ventilator dependence(pressure support requirement between 8-15cm $H_2O$, and PEEP requirement between 5-10cm $H_2O$), so tracheostomy was being considered. After removing the endotracheal tube, NPPV was applied using facial mask. Respiratory rate, arterial blood gas, pressure support level, and PEEP level were monitored just before intended extubation, at 30 minutes, 1 to 6, 6 to 12, 12 to 24 hours, 2nd day, and 3rd day following initiation of NPPV, and just before weaning from NPPV. The successful weaning was defined as spontaneous breathing off the ventilator for 48 hours or longer without respiratory distress. Results: The weaning through NPPV after intended extubation was successful in 7(50%) of 14 trials, and tracheostomy could be avoided in them. There were no differences in age, sex, APACHE III score, duration of invasive mechanical ventilation, baseline respiratory rate, $PaCO_2$ $PaO_2/FiO_2$, and ventilatory requirement(PS and PEEP) between the success and failure groups. In the success group, respiratory rate, pH, $PaCO_2$, and $PaO_2/FiO_2$ were not different between invasive MV and NPPV period. But in the failure group, pH decreased after 30 minutes of NPPV initiation compared with that of invasive MV($7.40\pm0.08$ vs. $7.34\pm0.06$, p<0.05). The causes of failure were worsening of ABG(n=3), retained tracheal secretion(n=2), mask intolerance(n=1), and flail chest(n=1). Conclusion: NPPV may be worth trying as a bridge method in weaning patients on long-term invasive mechanical ventilation.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.380-387
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• 1998

Background: Minimal pressure support(PSmin) is a level of pressure support which offset the imposed work of breathing(WOBimp) developed by endotracheal tube and ventilator circuits in pressure support ventilation While the lower applied level of pressure support compared to PSmin could induce respiratory muscle fatigue, the higher level than PSmin could keep respiratory muscle rest resulting in prolongation of weaning period during weaning from mechanical ventilation PSmin has been usually applied in the level of 5~10 cm$H_2O$, but the accurate level of PSmin is difficult to be determinated in individual cases. PSmin is known to be calculated by using the equation of "PSmin = peak inspiratory flow rate during spontaneus ventilation$\times$total ventilatory system resistance", but correlation of calculated PSmin and measured PSmin has not been known. The objects of this study were firstly to assess whether customarily applied pressure support level of 5~10 cm$H_2O$ would be appropriate to offset the imposed work of breathing among the patients under weaning process, and secondly to estimate the correlation between the measured PSmin and calculated PSmin. Method : 1) Measurement of PSmin : Intratracheal pressure changes were measured through Hi-Lo jet tracheal tube (8mm in diameter, Mallinckroft, USA) by using pulmonary monitor(CP-100 pulmonary monitor, Bicore, USA), and then pressure support level of mechanical ventilator were increased until WOBimp was reached to 0.01 J/L or less. Measured PSmin was defined as the lowest pressure to make WOBimp 0.01 J/L or less. 2) Calculation of PSmin : Peak airway pressure(Ppeak), plateau airway pressure(Pplat) and mean inspiratory flow rate of the subjects were measured on volume control mode of mechanical ventilation after sedation. Spontaneous peak inspiratory flow rates were measured on CPAP mode(O cm$H_2O$). Thereafter PSmin was calculated by using the equation "PSmin = peak inspiratory flow rate$\times$R, R = (Ppeak-Pplat)/mean inspiratory flow rate during volume control mode on mechanical ventilation". Results: Sixteen patients who were considered as the candidate for weaning from mechanical ventilation were included in the study. Mean age was 64(${\pm}14$) years, and the mean of total ventilation times was 9(${\pm}4$) days. All patients except one were males. The measured PSmin of the subjects ranged 4.0~12.5cm$H_2O$ in 14 patients. The mean level of PSmin was 7.6(${\pm}2.5\;cmH_2O$) in measured PSmin, 8.6 (${\pm}3.25\;cmH_2O$) in calculated PSmin Correlation between the measured PSmin and the calculated PSmin is significantly high(n=9, r=0.88, p=0.002). The calculated PSmin show a tendancy to be higher than the corresponding measured PSmin in 8 out of 9 subjects(p=0.09). The ratio of measured PSmin/calculated PSmin was 0.81(${\pm}0.05$). Conclusion: Minimal pressure support levels were different in individual cases in the range from 4 to 12.5 cm$H_2O$. Because the equation-driven calculated PSmin showed a good correlation with measured PSmin, the application of equation-driven PSmin would be then appropriate compared with conventional application of 5~10 cm$H_2O$ in patients under difficult weaning process with pressure support ventilation.

• The Korean Nurse
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• v.35 no.2
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• pp.71-91
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• 1996

The objectives of thes study were to identify the need for equipment development in nursing, and to determine the priorities for that development. The study was descriptive study done between March 2 and May 30, 1995, in which the subjects, including 421 patients, 223 family members, and 198 nurses from neurosurgery, orthopedic, rehabilitation medicine, internal medicine and intensive care units of nine general hospitals in Seoul, completed a questionnarie developed by the research team. The questionnaire consisted of 35 open and closed questions. Data was analyzed using frequencies and percentages. The results ware summarized as follows: 1) The average age of the nurses was 27.9 years, 48% of the patients were between 20 and 40 years of age, and 17% were over 60. The average lingth of experience for the nurse subjects was four years five months with 36.9%. having over five years experience. The most frequent diagnoses of patients were spinal disc(35.9%), internal medicine disease(26.0%), cerebral vascular accident(16.6%) and spinal cord injury(10%) 2) Many of the nurses(96.4%) reported deficiencies with existing equipment and 96.5% of the nurses, but only 79.8% of the patients, nurses' time. Further, 82.3% of the nurses and 75.8% of the patients felt that the development of new equipment would lead to a decrease in the cost of nursing care. 3) Nurses felt that the greatest areas of inconvenience were patient feeding(71.7%), hygiene(71.2%), caring for a patient confined to bed(70.7%), patient clothing(67.2%), mobility transfers(63.5%) and urinary elimination(52.0%). However, patients and family members listed the following as being the most inconvenient: urinary elimination(58.7%), Hygiene(50.5), feeding(48.4%), mobility transfers(47.1%) and bed care(45.2%). 4) Generally the nurses listed more inconveniences and patients and family members listed more demands for the development of equipment. These included utensils with large handles, and regulators for tube feedings; mattresses that provide for automatic position change and massage, which have patient controlled levers and a place for bed pan insertion; automatic lifts or transfer from bed to wheelchair; equipment to facilitate washing and oral hygiene as well as equipment that will allow patients with spinal cord injuries easy access to showers; a bed pan/urinal for women that is comfortable and effective from which urine can be measured and disposed of easily; disposable dressing sets and tracheostomy care sets and a convenient way of measuring changes in wound size; a safe delivery system for oxygen, a variety of mask sizes and better control of humidity, tracheal material than at present, as well as a communication system for patients with tracheostomies; clothing that will allow access to various parts of the body for treament or assessment without patients having to remove all of their clothing; and finally a system that will allow the patient to control lighting, telephones and pagers. Priority areas for equipment development reported by the nurses were, urinary elimination(58. 7%), hygiene(50.5%), feeding(48.4%), mobility transfers(47..1%), bowel elimination(40.8%). Those reported by the patients family members were feeding(71.7%), hygiene(70.0%), bedcare(70.7%), clothing(67.2%), mobility transfers(63.6%), urinary elimination(52.9%) and bowel elimination(50.5%) Altogether, nurses, patients and family members listed the following as priorities; clothing (178), bed care(144), urinary elimination(92), environment(81), hygiene(70). Further, a health professional forum listed urinary elimination, oxygen delivery, medication delivery, mobility transfers, bed care and hygiene in that order as priority areas. From this study it can be concluded that the first need is to develop equipment that will address the problems of urinary elimination. To do (l)This nurses who are interested in equipment development should organize an equipment development team to provide a forum for discussion and production of equipment for nursing.

• Korean Journal of Head & Neck Oncology
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• v.14 no.2
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• pp.236-243
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• 1998

Objectives: Local invasion of the thyroid cancer that is invasion of the upper aerodigestive tract, neurovascular structures of the neck and superior mediastinum, is infrequent and comprises of 1-16% of well-differentiated thyroid cancer. However the proximity of the thyroid gland to these structures provides the means for an invasive cancer to gain ready access into theses structures and when invasion occurs, it is the source of significant morbidity and mortality. So locally invasive thyroid cancer should be removed as much as possible, but still much debates have been exist whether the surgical method should be radical or conservative. This study was desinged to evaluate the clinical characteristics and the surgical treatment of the locally invasive thyroid cancer. Material and Methods: At the department of otorhinolaryngology of Hallym university, 10 patients diagnosed as locally invasive thyroid cancer among the 81 patients treated for thyroid cancer between 1991 to 1997 were retrospectively evaluated. Results: Of the 10 patients, 3 patients had histories of previous surgical treatment with or without radiation or radioactive iodine therapy. The site of invasion of thyroid cancer were trachea(7 cases), recurrent laryngeal nerve(5 cases), mediastinal node(5 cases), esophagus(3cases), larynx(3cases), carotid artery(3 cases), pharynx(l case), and other sites(4 cases). The operation techniques included 1 partial laryngectomy and 1 partial cricoid resection, 2 shavings and 3 window resections of the trachea, 1 sleeve resection of the trachea with end-to-end anastomosis and 1 cricotracheoplasty for tracheal invasion, 2 shavings and 1 partial esophagectomies for esophageal invasion, and 1 wall shaving and 2 partial resections with $Gortex^{\circledR}$ tube reconstruction for carotid artery invasion, and so on. Conclusions: These data and review of literature suggest that the surgical method should be perfomed on the basis of individual condition and complete removal of all gross tumor with preservation of vital structures whenever possible will offer a good result.