Intensive treatment of respiratory failure--personal experiences

Controlled oxygen-therapy was used in 30 out of 49 patients (61%) with the acute respiratory failure or exacerbations of the chronic respiratory failure treated at ICU (Group Y), while artificial ventilation in the remaining 19 patients (39%; Group B). An improvement was achieved in 70% of patients of Group A and 42% in Group B. Overall improvement was achieved in 59% of the treated patients. There were 69% of treated patients with infections. Totally 41% of the treated patients died (30% of Group A and 58% of Group B). An analysis of the results has been carried out in various subgroups of the treated patients, i.e. the acute and exacerbated respiratory failure as well as partial and complete respiratory insufficiency. The result of high risk patients have also been analysed. This subgroup included sudden cardiac arrest, shock and non-compensated acidosis. Favourable effects of the intensive care of patients with infections have been discussed with particular reference to the life hazard in case of septic complications. Emphasis is on the unfavorable effects of therapy in patients with respiratory failure complicated with pulmonary embolism. Indications to the use of respirator and complications of the artificial ventilation have been discussed.     

Guillain-Barré syndrome: rehabilitation outcome and recent developments.

Guillain-Barré syndrome is the most common polyneuropathy causing major disability and respiratory failure. Respiratory complications are the main cause of death. Improved respiratory care and new treatment strategies such as plasmaphoresis and immunoglobulin have been shown to improve outcome. We studied the course and outcome of 37 patients with Guillain-Barré syndrome who were admitted to a rehabilitation and respiratory care facility over a 10-year period. There were 21 males and 16 females with a mean age of 62+/-3 years. Fourteen patients developed respiratory failure requiring endotracheal intubation and mechanical ventilation. The mean duration of mechanical ventilation was 38+/-10 days. All patients were successfully liberated from the ventilator. However, 83 percent of the patients were moderately to severely disabled at the time of discharge. Thirteen out of 37 (35 percent) developed long-term disability. None of the patients died over the period of follow-up. These results indicate that early recognition and treatment of respiratory complications in Guillain-Barré syndrome could reduce the morbidity and mortality of this condition.     

机械通气患者人工气道管理技术进展

机械通气技术在严重急慢性呼吸衰竭的患者抢救治疗中广泛应用,人工气道管理技术方法在机械通气过程中显示十分重要作用,有效的气道管理技术方法可减少机械通气过程中一些并发症如呼吸机相关性肺炎等。结合临床应用机械通气技术体会,本文主要对人工气道管理技术方法总结分析。     

Randomised comparison of percutaneous endoscopic gastrostomy and nasogastric tube feeding in patients with persisting neurological dysphagia.

OBJECTIVE--To compare percutaneous endoscopic gastrostomy and nasogastric tube feeding in patients with persisting neurological dysphagia. DESIGN--Randomised 28 day study of inpatients requiring long term enteral nutrition. SETTING--Three Glasgow teaching hospitals. SUBJECTS--40 patients with dysphagia for at least four weeks secondary to neurological disorders: 20 patients (10 women) were randomised to nasogastric feeding and 20 (eight women) to endoscopic gastrostomy. MAIN OUTCOME MEASURES--Treatment failure (blocked or displaced tubes on three or more occasions or refusal to continue treatment); duration of feeding; intake of liquid diets; complications; nutritional status at end of trial. RESULTS--One patient in each group died before starting feeding. Treatment failure occurred in 18 of the 19 nasogastric patients and in none of the gastrostomy group. The mean (SE) duration of feeding for the nasogastric group was 5.2 (1.5) days. No complications occurred in the nasogastric group but three (16%) of the gastrostomy group developed minor problems (aspiration pneumonia (two patients) wound infection (one)). Gastrostomy patients received a significantly greater proportion of their prescribed feed (93% (2%)) compared with the nasogastric group, (55% (4%); p less than 0.001) and also gained significantly more weight after seven days of feeding (1.4 (0.5) kg v 0.6 (0.1) kg; p less than 0.05). Analyses at days 14, 21, and 28 were not possible due to the small numbers remaining in the nasogastric group. CONCLUSION--Percutaneous endoscopic gastrostomy tube feeding is a safe and effective method of providing long term enteral nutrition to patients with neurological dysphagia and offers important advantages over nasogastric tube feeding.     

Noninvasive positive-pressure ventilation in acute respiratory failure

Noninvasive positive-pressure ventilation is a type of mechanical ventilation that does not require an artificial airway. Studies published in the 1990s that evaluated the efficacy of this technique for the treatment of diseases as chronic obstructive pulmonary disease, congestive heart failure and acute respiratory failure have generalized its use in recent years. Important issues include the selection of the ventilation interface and the type of ventilator. Currently available interfaces include nasal, oronasal and facial masks, mouthpieces and helmets. Comparisons of the available interfaces have not shown one to be clearly superior. Both critical care ventilators and portable ventilators can be used for noninvasive positive-pressure ventilation; however, the choice of ventilator type depends on the patient''s condition and therapeutic requirements and on the expertise of the attending staff and the location of care. The best results (decreased need for intubation and decreased mortality) have been reported among patients with exacerbations of chronic obstructive pulmonary disease and cardiogenic pulmonary edema.Noninvasive positive-pressure ventilation is the delivery of mechanical ventilation to patients with respiratory failure without the requirement of an artificial airway. The key change that led to the recent increase in the use of this technique occurred in the early 1980s with the introduction of the nasal continuous positive airway pressure mask for the treatment of obstructive sleep apnea. Studies published in the 1990s that evaluated the efficacy of noninvasive positive-pressure ventilation for treatment of diseases such as chronic obstructive pulmonary disease, congestive heart failure and acute respiratory failure have generalized its use in recent years.¹ In 1998, an international study on the use of mechanical ventilation found that 5% of patients admitted to intensive care units received noninvasive positive-pressure ventilation.²Noninvasive positive-pressure ventilation includes various techniques for augmenting alveolar ventilation without an endotracheal airway. The clinical application of noninvasive ventilation by use of continuous positive airway pressure alone is referred to as “mask CPAP,” and noninvasive ventilation by use of intermittent positive-pressure ventilation with or without continuous positive airway pressure is called noninvasive positive-pressure ventilation.     

Fetal intracardiac transfusions in patients with severe rhesus isoimmunisation

Six patients with pregnancies of 19-31 weeks'' duration showing evidence of erythroblastosis fetalis were treated with 25 fetal intracardiac blood transfusions. Complications related to the procedure occurred on five occasions in three patients. In two of the six patients the fetus died, but it was unlikely that death was related to the intracardiac transfusions.Fetal intracardiac blood transfusion may result in potentially severe complications but offers an alternative when transfusion cannot be performed into the umbilical cord.     

Risk factors of pseudomonas infection in hemoblastosis patients

A total of 67 patients with diseases of the blood system and infectious complications, admitted to the Hematological Department of the Novosibirsk Regional Clinical Hospital, were examined. For this study only patients with etiologically established diagnosis were taken. The study revealed that Pseudomonas sp., whose strains were susceptible to Ceftazidime in 100% of cases and resistant to Cefepime and Imipenem in 15-17% of cases, was the etiological agent of 13.6% of all cases of infectious complications in hemoblastosis patients. Infectious lesions of pulmonary parenchyma, the presence of chronic diseases of the respiratory tract in the medical history, neutropenia, artificial ventilation of the lungs were found to be adverse prognostic factors with respect to a high risk of Pseudomonas infection in such patients. Therapy with glucocorticosteroids and cytostatics, preceding antibacterial prophylaxis were not linked with the isolation of Pseudomonas from the patients exhibiting the same levels of lethality and severity of infectious complications.     

电刺激兔脑干中缝背核引起呼吸易化效应的观察

本文在30只全麻、制动、断双侧迷走神经的家兔上,记录一侧膈神经放电,观察了电刺激脑干中缝背核(Nucleus Raphe Dorsalis,NRD)所诱发出的呼吸效应。1.施以6—10s 长串电脉冲刺激(波宽0.3ms,频率100Hz,波幅4—6V),诱发出了强的呼吸易化效应,使呼吸加深加快。2.吸气相给予0.4s 短串电脉冲刺激可以明显的延长吸气相,用0.15mA 强度刺激,落位在吸气相的2/3时效应最明显。3.呼气相短串电脉串刺激可规律地使呼气时程缩短,促进呼气向吸气的位相转换,诱发此效应出现的强度阈值在呼气相中逐渐降低。     

Effect of sleep on nocturnal bronchoconstriction and ventilatory patterns in asthmatics

To assess the effect of sleep on airflow resistance and patterns of ventilation in asthmatic patients with nocturnal worsening, 10 adult subjects (6 asthmatic patients with nocturnal worsening, 4 normal controls) were monitored overnight in the sleep laboratory on two separate occasions. During 1 night, subjects were allowed to sleep normally, whereas during the other night all sleep was prevented. The six asthmatic patients demonstrated progressive increases in lower airway resistance (Rla) on both nights, but the rate of increase was twofold greater (P less than 0.0001) during the sleep night compared with the sleep prevention night. However, overnight decrements in forced expired volume in 1 s (FEV1) were similar over the 2 nights. The asthmatic patients maintained their minute ventilation as Rla increased during sleep, demonstrating a stable tidal volume with a mild increase in respiratory frequency. We conclude that in asthmatic patients with nocturnal worsening 1) Rla increases and FEV1 falls overnight regardless of sleep state, 2) sleep enhances the observed overnight increases in Rla, and 3) sleep does not abolish compensatory ventilatory responses to spontaneously occurring bronchoconstriction.     

Voluntary and Involuntary Control of Breathing with Imposed Ventilation Parameters

To clarify the mechanisms of interaction between voluntary and involuntary control of respiratory movements in a waking human, respiratory patterns were studied during self-controlled artificial ventilation used in place of natural breathing. Seven subjects controlled both the duration of artificial inhalations and the flow rate of air at excess pressure, continuously adjusting their actions to obtain the sensation of comfortable breathing. At rest, pulmonary ventilation was higher during self-controlled artificial breathing than during natural breathing. This trend was also noted during exercise. A correlation was observed between the velocity of the movement that started air flow and the artificial ventilation volume (r = 0.91). During self-controlled artificial breathing, the subjects sometimes took natural breaths. Natural inhalations did not influence the beginning or end of an artificial inhalation. Information received from respiratory receptors was assumed to play a certain role in the self-control of artificial breathing.     

Effects of Adaptive Support Ventilation and Synchronized Intermittent Mandatory Ventilation on Peripheral Circulation and Blood Gas Markers of COPD Patients with Respiratory Failure

The objective of the study was to investigate the effects of adaptive support ventilation (ASV) and synchronized intermittent mandatory ventilation (SIMV) on peripheral circulation of chronic obstructive pulmonary disease (COPD) patients with respiratory failure. 86 COPD patients with respiratory failure were recruited in this study. Self-control method was used to compare the effect of ASV and SIMV on the parameters of ventilation machine, heart rate, blood pressure, central venous pressure (CVP), and blood gas markers. When the patients in ASV and SIMV groups were compared, respiratory rate, tidal volume, and peak airway pressure (PIP) showed significant difference. When minute ventilation (MV) was compared, no significant difference was shown. When peripheral circulation parameters were compared, peripheral circulation heart rate, SBP, DBP, and CVP showed significant difference. Compared with SIMV group, PaO₂, pH, and SaO₂ values were remarkably increased (P < 0.01) while no significant difference was found for partial pressure of carbon dioxide (pCO₂) when two groups were compared. In conclusion, when mechanical ventilation was used in COPD patients with respiratory failure, ASV can significantly improve clinical outcomes.     

The functional significance of ventilation frequency,and its relationship to oxygen demand in the resting brown long-eared bat,Plecotus auritus

Summary Mean oxygen consumption and simultaneous ventilation frequency of nine non-reproductive brown long-eared bats (body mass 8.53–13.33 g) were measured on 159 occasions. Ambient (chamber) temperature at which the measurements were made ranged from 10.8 to 41.1°C. Apneic ventilation occurred in 22 of the 59 measurements made when mean oxygen consumption was less than 0.5 ml·min^-1. No records of apneic ventilation were obtained when it was over 0.5 ml·min^-1. The relationship between ventilation frequency and mean oxygen consumption depended on whether ventilation was apneic or non-apneic. When ventilation was non-apneic the relationship was positive and log-linear. When ventilation was apneic the relationship was log-log. Within the thermoneutral zone ventilation frequency was not significantly different from that predicted from allometric equations for a terrestrial mammal of equivalent body mass, but was significantly greater than that predicted for a bird. A reduction in the amount of oxygen consumed per breath occurred at ambient temperatures above the upper critical temperature (39°C).Abbreviations RH relative humidity - T _a chamber temperature - vf ventilation frequency - VO₂ oxygen consumption     

针刺疗法联合穴位贴敷对急性呼吸衰竭机械通气患者血气分析指标、膈肌功能及炎症免疫指标的影响

摘要 目的：观察穴位贴敷、针刺疗法联合治疗对急性呼吸衰竭机械通气患者血气分析指标、膈肌功能及炎症免疫指标的影响。方法：选择2021年11月～2022年12月期间在安徽中医药大学附属六安医院接受治疗的92例急性呼吸衰竭机械通气患者,按照随机数字表法将患者分为对照组（常规治疗,46例）和研究组（对照组的基础上增加针刺疗法联合穴位贴敷治疗,46例）。对比两组血气分析指标、膈肌功能、炎症免疫指标及胃肠功能,同时记录两组并发症发生率。结果：研究组撤机前氧合指数（OI）、pH、动脉血氧分压（PaO2）高于对照组,动脉血二氧化碳分压（PaCO₂）低于对照组（P<0.05）。研究组撤机前右侧膈肌呼气末厚度（Tdi-ee）、吸气末厚度（Tdi-ei）、膈肌增厚分数（TFdi）低于对照组（P<0.05）。研究组撤机前超敏C反应蛋白（hs-CRP）、降钙素原（PCT）、白细胞计数（WBC）低于对照组,CD4⁺高于对照组（P<0.05）。研究组撤机前胃肠功能评分低于对照组（P<0.05）。两组并发症发生率组间对比无统计学差异（P>0.05）。结论：针刺疗法联合穴位贴敷在改善急性呼吸衰竭机械通气患者的血气分析指标、膈肌功能、炎症免疫指标中的应用价值较好。     

Early neurological complications of coronary artery bypass surgery.

A prospective study of 312 patients undergoing elective coronary artery bypass surgery was undertaken to determine the incidence, severity, and functional impact of postoperative neurological complications. Detailed evaluation of the patients showed that neurological complications after surgery were common, occurring in 191 of the 312 patients (61%). Although such a high proportion of the total developed detectable changes, serious neurological morbidity was rare. Neurological disorders resulted in death in only one patient (0.3%) and severe disability in only four (1.3%). Forty eight patients were mildly disabled during the early postoperative period, and the remaining 138 with neurological signs had no serious functional disability. The postoperative neurological disorders detected included one death from cerebral hypoxic damage. Prolonged depression of conscious level was observed in 10 patients (3%) and definite stroke in 15 (5%); 78 (25%) developed ophthalmological abnormalities and 123 (39%) primitive reflexes; postoperative psychosis was observed in four (1%); and 37 (12%) developed disorders of the peripheral nervous system. The incidence of serious neurological problems such as fatal cerebral damage, stroke, and brachial plexopathy is in accordance with experience elsewhere. Lesser abnormalities, whose detection required detailed neurological examination, were much commoner than expected from previous reports.     

Asthma deaths in Cardiff 1963-74: 53 deaths in hospital.

In a study of factors associated with death from bronchial asthma in hospital 53 patients were investigated. Typically the fatal attack persisted for several days before admission to hospital and normally occurred in patients with a long history of asthma. The patient or doctor often underestimated the severity of the attack. On admission most patients were severely ill, and over a third died within 24 hours. Peak flow rate and blood gases were rarely measured. Corticosteroid treatment was often underused, and patients rarely received assisted ventilation before death. Infection played a part in 14 deaths, five of them associated with assisted ventilation. Admitting asthmatics to a special respiratory ward with facilities for standardised assessment and treatment and introducing a self-admission service may help to prevent some of these deaths.     

ICU机械通气并发下呼吸道医院感染病原菌的调查分析

目的：分析ICU机械通气并发下呼吸道医院感染病原学构成及耐药情况。为临床防治提供依据。方法：对我院1996年6月-1999年6月3间ICU收住的98例机械通气合并下呼吸道医院感染患者的致病菌及药敏结果进行回顾性调查。结果：共检出致病毒128株,其中革兰阴性细菌（G^-菌）占66.4%（85株）,革兰阳性细菌（G^ 菌）占25.8%(33株）,真菌占7.8%(10株）;前四位致病菌分别为铜绿假单胞菌（24株）,革兰阳性细菌（G^ 菌）占25.8%(33株）,真菌占7.8%(10株）;前四位致病菌分别为铜绿假单胞菌（24株）,金黄色葡萄球菌（22株）,不动杆菌属（21株）,肠杆菌属（18株）,药敏结果显示这类菌株多重耐药现象严重。结论：ICU机械通气并发下呼吸道医院感染病原体构成以G^-菌为主,其药敏试验呈多重耐药,临床应重视病原学检查,开展细菌耐药性监测,合理使用抗菌药物。     

Compliance, blood gases, and acid-base balance in guinea pigs artificially ventilated with different IPPV patterns

In order to estimate optimum parameters for artificial ventilation of adult guinea pigs, the effect of four hours intermittent positive pressure ventilation (IPPV) was studied using different tidal volumes (VT), respiratory frequencies (f), and minute volumes (Ve). Total compliance was measured by placing the animal in a whole body plathysmograph, the arterial blood gases, pH and base excess by catheterizing the carotid artery. In Series I 9 guinea pigs were ventilated at parameters adapted to the spontaneous breathing pattern (VT = 2 ml, f = 70 breaths.min-1). This ventilatory pattern resulted in severe disorders in compliance, gas exchange, and acid-base balance. In Series II 3 different VT (2, 6, 10 ml) were studied by changing f so that Ve was kept constant. The results demonstrated a favourable effect of slow and deep ventilation upon lung mechanics and oxygenation. In Series III 3 different Ve (300, 250, 200 ml.min-1) were tested using a constant VT = 10 ml. Optimum parameters for artificial ventilation of adult guinea pigs were: VT = 10 ml and f = 20 breath--min-1 which resulted in stable compliance, good O2-saturation, normocapnia and normal acid-base balance.     

A Characterization of the Oral Microbiome in Allogeneic Stem Cell Transplant Patients

Background

The mouth is a complex biological structure inhabited by diverse bacterial communities. The purpose of this study is to describe the effects of allogeneic stem cell transplantation on the oral microbiota and to examine differences among those patients who acquired respiratory complications after transplantation.

Methodology/Principal Findings

All patients were consented at the National Institutes of Health, Clinical Center. Bacterial DNA was analyzed from patients'' oral specimens using the Human Oral Microbe Identification Microarray. The specimens were collected from four oral sites in 45 allogeneic transplantation patients. Specimens were collected at baseline prior to transplantation, after transplantation at the nadir of the neutrophil count and after myeloid engraftment. If respiratory signs and symptoms developed, additional specimens were obtained. Patients were followed for 100 days post transplantation. Eleven patients'' specimens were subjected to further statistical analysis. Many common bacterial genera, such as Streptococcus, Veillonella, Gemella, Granulicatella and Camplyobacter were identified as being present before and after transplantation. Five of 11 patients developed respiratory complications following transplantation and there was preliminary evidence that the oral microbiome changed in their oral specimens. Cluster analysis and principal component analysis revealed this change in the oral microbiota.

Conclusions/Significance

After allogeneic transplantation, the oral bacterial community''s response to a new immune system was not apparent and many of the most common core oral taxa remained unaffected. However, the oral microbiome was affected in patients who developed respiratory signs and symptoms after transplantation. The association related to the change in the oral microbiota and respiratory complications after transplantation will be validated by future studies using high throughput molecular methods.     

经鼻盲探气管插管在抢救呼吸衰竭病人中的应用

目的比较经鼻盲探气管插管和气管切开在抢救呼吸衰竭病人的治疗效果。方法回顾性对比分析同期ICU住院病人采用经鼻盲探气管插管或气管切开建立人工气道后的病情转归,使用呼吸机后血气纠正时间,使用呼吸机时间,留置气管导管时间,平均住院时间及操作并发症。结果经鼻盲探气管插管组拔管率42.9%(9/21例),拔管成功率100%(9/9例);气管切开组拔管率60.7%(17/28例),拔管成功率76.5%(13/17例),两组间比较无显著性差异(P<0.05)。使用呼吸机后血气纠正时间无明显差别,但经鼻盲探气管插管组使用呼吸机时间,留置气管导管时间,平均住院时间均短于气管切开组(P<0.05)。气管切开组操作导致的并发症发生率46.4%(13/28例),而经鼻盲探气管插管组操作导致的并发症发生率23.8%(5/21例),明显少于前者(P<0.01)。结论经鼻盲探气管插管操作简便、实用,能减少并发症,缩短使用呼吸机时间,留置气管导管时间及住院时间,在抢救呼吸衰竭病人中较气管切开术有更好的临床应用价值。     

Respiratory insufficiency in patients with myasthenia gravis

We evaluated 20 patients who required prolonged mechanical ventilation for respiratory failure associated with myasthenia gravis. All 20 patients survived and were weaned from the ventilator after 3 to 14 days (mean 6.5 days) of respiratory support. Progressing bulbar symptoms and respiratory infection were the most frequent causes of the myasthenic crisis. During a period of assisted mechanical ventilation, anticholinesterase medication was interrupted and the patients were treated with steroids and antibiotics. Plasmapheresis may be considered in the management of myasthenic crisis.