Ventilatory support in facioscapulohumeral muscular dystrophy.

Respiratory insufficiency due to respiratory muscle weakness is a common complication of many neuromuscular diseases. The prevalence of respiratory failure in facioscapulohumeral muscular dystrophy (FSHD) is unknown. The authors identified 10 FSHD patients on nocturnal ventilatory support at home, representing approximately 1% of the Dutch FSHD population. Severe muscle disease, wheelchair dependency, and kyphoscoliosis appeared to be risk factors for respiratory failure.

[The symptomatic treatment of amyotrophic lateral sclerosis]. / De symptomatische behandeling van amyotrofische laterale sclerose.

Patients with amyotrophic lateral sclerosis (ALS) have symptoms of progressive muscle weakness, of disturbed speech and swallowing, and in the terminal phase those of respiratory weakness. Treatment options, in particular those for excessive weight loss and respiratory weakness, should be introduced to the patients and their families when the patient is emotionally capable and before dysarthria severely hampers communication. Special equipment for keeping the patient as mobile as possible should be made available much earlier than in the case of other diseases of the muscles as in ALS progression is much faster. Cramps, pathological crying or laughter, spasms, and spasticity can all be treated by medication. When speech can no longer be understood, adaptive strategies such as sign language, mime, posture and communication apparatus varying from a note pad to advanced computer systems can be used. Sialorrhoea, caused by difficulty swallowing with its accompanying danger of aspiration can be halted by the use of medication, by radiotherapy and by the injection into the salivary glands of botulin A toxin. Weight loss, also a result of dysphagia, can be avoided by eating frequent small meals or if necessary performing a percutaneous endoscopic or radiological gastroscopy. Excess mucus in the respiratory tract can be treated with anticholinergics. Difficulty in coughing up thick and sticky mucus cannot always be adequately helped. Respiratory weakness is treatable by external respiratory supportive therapy using a nasal mask, as well as invasive respiratory support via a trachcostoma and by treating the symptoms of respiratory weakness. The latter form of treatment is palliative and forms part of terminal care. During the terminal phase restlessness, anxiety, pain, and dyspnoea require the most attention. Treatment requires careful multidisciplinary cooperation.

[Amyotrophic lateral sclerosis: mechanical ventilation--or not right?]. / Amyotrofische laterale sclerose: beademen--of juist niet?

In two patients (men aged 64 and 62 years, respectively) with amyotrophic lateral sclerosis (ALS) tracheostomy ventilation was initiated following (imminent) acute respiratory failure; in one patient this was done because advance directives were lacking, while in the other non-invasive ventilation (NIPPV) was no longer an option. A third ALS patient, a woman aged 36 years, already had chronic respiratory failure when she presented at the local centre for home mechanical ventilation. As a result, the placement of a percutaneous endoscopic gastrostomy (PEG) was impossible. Instead, she had to use a nasopharyngeal feeding tube, which diminished the effectiveness of her NIPPV. The fourth patient, a man aged 60 years, was referred in good time and hence had sufficient time to consider domiciliary ventilation. Following the placement of a PEG he started NIPPV electively. In patients with ALS, domiciliary ventilation should be discussed early in the course of the disease. Advance directives with regard to domiciliary ventilation are important, not only to avoid undesired (invasive) ventilation, but also with respect to the placement of a PEG and the appropriate use of oxygen and morphine.

[International and Dutch reanimation guidelines]. / Internationale en nationale reanimatierichtlijnen.

The 'Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care' have been published in a number of journals by a group of international experts. Although these guidelines are not dictated or imposed, their implementation would necessitate changes to the curriculum 'Basic Life Support' instruction for laymen. The recall of all persons ever instructed to inform them about the new Guidelines is also necessary. However, in view of the present lack of solid scientific basis, the wisdom of implementing the present guidelines in Dutch practice in an unrestricted manner has to be questioned, due to financial and human impact that would be involved.

[Resuscitation: CAB versus ABC]. / Reanimatie: CAB versus ABC.

In the resuscitation guidelines revised by the Netherlands Resuscitation Council, the decision has been made to conform with the resuscitation flowchart used elsewhere in the world, and to use the ABC sequence: 'airway-breathing-circulation'. This implies that the CAB sequence ('circulation-airway-breathing'), which has been in use since 1981, has been abandoned. Intrinsic arguments in favour of the CAB scheme are based on animal experiments and observations in humans. They come down to time-saving in the various diagnostic and therapeutic steps, whereby the chance of successful recovery of the circulation increases, and the convalescence phase and the risk of brain damage probably are reduced. In addition, this scheme is better suited to the relatively large group of patients with a cardiac cause underlying their loss of consciousness, and to the preference of lay people to limit themselves to heart massage when attending the patient. Intrinsic arguments in favour of the ABC scheme are not based on scientific data. They concern improvement of the ventilation-perfusion ratio with the first heart massage, oxygenation of the blood in the lung capillaries, improvement of the circulation and the palpability of pulses.

Psychosocial problems arising from home ventilation.

OBJECTIVE: To study psychosocial questions and problems of patients, who are chronically dependent on artificial ventilation, and their families. DESIGN: A total of 38 patients and family members (n = 43) were randomly selected. Several patients (n = 12) received respiratory support by nasal mask; the majority (n = 26) received respiratory support via a tracheotomy tube. Semistructured interviews were conducted. The Visual Analog Scale was also used. The extent to which the illness and chronic respiratory support were experienced as emotionally stressful, both by the patients and family members, was marked, on a scale ranging from 0 (light) to 10 (severe). RESULTS: Differences and similarities in the problems experienced were found among the patients and their families. Particularly in the case of patients receiving respiratory support by tracheostomy ventilation 24 hr/day, emotional stress on the family caregivers increased during the course of years. That the patient should urgently require bronchial suctioning at any moment made caregivers very anxious. However, several patients demonstrated increased skills in survival coping strategies. Despite diverse problems, the patients and their caregivers would elect to receive respiratory support, if the opportunity arose. CONCLUSIONS: In the case of chronically ill patients who receive continuous respiratory support via a tracheotomy tube, there is greater need for psychosocial support. Family members, who must be available 24 hr a day, need psychosocial support, professional home care, and voluntary assistance that have not been previously offered.

[Mechanical ventilation in neuromuscular diseases: do not start too early, but certainly not too late]. / Beademing bij neuromusculaire ziekten: niet te vroeg beginnen, maar zeker niet te laat.

Three patients had chronic respiratory disorders: a 42-year-old man with glycogenosis type II was tired, had headaches, poor pulmonary function values and, according to the arterial blood gas values, hypercapnia; a man aged 24 with Duchenne's muscular dystrophy had variable moderate dyspnoea with hypoxia and hypercapnia, and a man aged 64 years with an mitochondrial myopathy complained of dyspnoea and headache but had good blood gas values. The symptoms and abnormalities of the first patient were suppressed by nocturnal ventilatory support through a nasal mask system, the second preferred to refrain from ventilatory support and died a few weeks later and the symptoms of the third patient decreased without ventilatory support. Assessing a ventilatory disorder in patients with a neuromuscular disease is not always simple. Symptoms suggestive of nocturnal hypoventilation may occur in patients without respiratory insufficiency. It is also possible for patients with chronic respiratory insufficiency to be free of symptoms. Determinations of the arterial blood gas values are the most reliable method. Since normal daytime values do not exclude a nocturnal respiratory insufficiency, it is advisable in case of suspicion of nocturnal hypoventilation to measure the arterial blood gas values at night, as well. Nocturnal pulse oximetry does not always adequately reflect the degree of hypoventilation. In view of the positive effects of assisted respiration, adequate diagnostic examinations and early referral to a centre for home mechanical ventilation are advisable.

Neuromuscular scoliosis: clinical evaluation pre- and postoperative.

Neuromuscular scoliosis concerns a wide variety of disorders, all with a different approach to surgical intervention. The impact of these disorders on a patient is discussed in terms of pulmonary, cardiac, bowel and bladder function and complications in the perioperative and postoperative period such as gastric ulcers, pathologic fractures, wound healing, and nutrition is described. These difficult patients need a multidisciplinary approach. The 'Utrecht team' set-up is described in an 'as we do it' way. Items on preoperative clinical and radiological examination are provided, as well as points of special attention in perioperative care. Early detection, decision-making and intervention makes it possible to correct and stabilize the spine in these children with a short stay in hospital and a quick recovery.

Prescription and usage of long-term oxygen therapy in patients with chronic obstructive pulmonary disease in The Netherlands.

Long-term oxygen therapy (LTOT) has been shown to improve survival in hypoxaemic patients with chronic obstructive pulmonary disease (COPD). This has resulted in recommending the prescription of oxygen for at least 15 h day-1 in most European countries. In order to examine the prescription and usage of LTOT and to assess the adherence to international recommendations for its prescription, a survey was set up in a random sample of clients of the largest oxygen company in the Netherlands. After patients had been visited for an interview, additional postal surveys were sent to the physician who had prescribed LTOT and to the oxygen company. For 175 COPD patients the mean oxygen prescription and mean oxygen usage were 15.6 +/- 5.8 and 14.1 +/- 6.8 h day-1, respectively. In 62 patients (35%) oxygen was prescribed < 15 h day-1, more often by non-chest physicians than by chest physicians (P < 0.0001), and 91 patients (52%) used oxygen < 15 h day-1. Of 113 patients with a prescription > or = 15 h day-1, 39 (35%) used oxygen < 15 h day-1 and 74 for > or = 15 h day-1. The latter were prescribed oxygen for more h day-1, had been longer on LTOT, had a higher resting flow rate, were prescribed a concentrator, employed portable cylinders and used oxygen in public significantly more often than the former. We conclude that in a selected group of LTOT patients with COPD both oxygen prescription and usage were often inadequate, particularly if LTOT was prescribed by non-chest physicians.

Hypothermia in trauma patients.

Accidental hypothermia (AH) can be defined as an unintentional decrease in core temperature below 35 degrees C during cold exposure by individuals without intrinsic thermoregulatory dysfunction. Pathophysiological changes can be attributed both to the severity of hypothermia and to co-morbid factors such as trauma, submersion, intoxication and underlying diseases. In trauma victims stratified according to the Injury Severity Score, the factor hypothermia is considered to be a poor prognostic sign for survival. In these patients rewarming therapy should be applied as soon as possible. In the Utrecht University Hospital, adult patients with AH are managed according to an algorithm based on their presenting hemodynamic conditions. Patients with perfusing cardiac rhythms and systolic pressures over 80 mmHg will receive continuous arteriovenous rewarming (CAVR). Arrested and hemodynamically instable patients are treated with cardiopulmonary bypass (CPB). In a 3-year period, 22 patients with AH were admitted to the emergency department. Fourteen patients had a trauma as the cause of hypothermia. Twenty patients were treated according to the algorithm (CAVR n = 18, CPB n = 2) and two patients were alternatively managed. Mortality in the CAVR group was 28% and total mortality reached 32%. Complications of CAVR are related to placement and removal of vascular catheters and may be severe in these patients with impaired coagulation. CAVR permits a good access to the (trauma-) patient and rewarming can be continued synchronously with diagnosis and treatment of various injuries.

Accuracy of oxygen delivery by liquid oxygen canisters.

The oxygen flow rate delivered by liquid oxygen canisters may be less than intended, owing to inaccuracies of the set flow rates and/or as a result of the outflow resistance caused by the humidifier, oxygen tubing, delivery or conserving device. The aim of this study was to investigate the accuracy of oxygen delivery by liquid oxygen canisters at different flow rates and levels of outflow resistance. Four stationary and 18 portable liquid oxygen canisters from three manufacturers were tested. All flows were measured using a Timemeter RT 200 Calibration Analyser. An adjustable obstruction was used to calculate the effect of the outflow resistance on the delivered flow rate. The measured and set flow rates of both stationary and portable canisters were strongly correlated. Expressed as a percentage of the set flow rate, the measured flow rate of the canisters varied from 36-128%, with the lowest values at flow rates <1 L x min(-1). Sixty-two (26%) of the measured flow rates differed > or =10% from the set flow rate. A difference of 0.5-1.0 L x min(-1) occurred in 16 (7%) of the measurements, but only at set flow rates >2 L x min(-1). Irrespective of the set flow rate, the measured flow rate was hardly affected by the outflow resistance. We conclude that the accuracy of oxygen delivery by liquid oxygen canisters depends on the inaccuracy of the set flow rates rather than on the outflow resistance, even at high flow rates. Although the differences between the measured and set flow rates were mostly small, they may have clinical significance, particularly in patients with chronic obstructive pulmonary disease. To prevent inaccuracy, monthly checks of the canisters by the oxygen provider at the patient's home are more important than yearly maintenance.

[Three patients with accidental hypothermia: customized rewarming]. / Drie patiënten met accidentele hypothermie; opwarmen op maat.

Three patients, two men aged 47 and 33 years and a woman aged 33 years, became hypothermic after an accident with body temperatures of 34.5, 26.2 and 23.1 degrees C, respectively. Two of them developed circulatory disorders, for which reanimation was performed. All three patients recovered after active external heating using among other things warmed infusion fluids, a warmed waterbed, continuous arteriovenous rewarming and rewarming with the heart-lung machine. For the treatment to be successful, the type of rewarming selected should be guided by the degree of hypothermia, the circulatory situation and the severity of the accessory injuries.

Instrumental variability of respiratory blood gases among different blood gas analysers in different laboratories.

The aim of this study was to test the hypothesis that differences in oxygen tension (PO2) and carbon dioxide tension (PCO2) values from measurements performed on different blood gas analysers in different laboratories are clinically insignificant. Samples of fresh whole human tonometered blood (PO2 8.1 kPa (60.8 mmHg); PCO2 5.3 kPa (39.9 mmHg)) were placed in airtight glass syringes and transported in ice-water slush. Blood gas analysis was performed within 3.5 h by 17 analysers (10 different models) in 10 hospitals on one day. The mean of the differences between the measured and target values was -0.01+/-0.19 and 0.21+/-0.13 kPa (-0.06+/-1.45 and 1.55+/-1.01 mmHg) for PO2 and PCO2, respectively. The mean of the differences between two samples on one analyser was 0.06+/-0.06 and 0.04+/-0.03 kPa (0.47+/-0.48 and 0.29+/-0.24 mmHg), respectively. For PO2 and PCO2 the interinstrument standard deviations (s(b)) were 0.18 and 0.13 kPa (1.38 and 0.99 mmHg), respectively, whereas the intra-instrument standard deviations (s) were 0.06 and 0.03 kPa (0.47 and 0.26 mmHg), respectively. Both for PO2 and PCO2 the ratios of s(b)2 and s2 were statistically significant (analysis of variance (ANOVA) p<0.001). The standard deviations of a random measurement on a random analyser were 0.19 and 0.14 kPa (1.46 and 1.02 mmHg) for PO2 and PCO2, respectively. We conclude that the variability in measurement of blood gas values among different blood gas analysers, although negligible, depends much more on inter- than intra-instrument variation, both for oxygen tension and carbon dioxide tension. Technical improvements and adequate quality control programmes, including tonometry, may explain why the variability in blood gas values depends mainly on errors in the pre-analytical phase.

Transtracheal oxygen therapy: an effective and safe alternative to nasal oxygen administration.

Transtracheal oxygen therapy (TTOT) improves the efficiency of oxygen delivery and overcomes the discomfort associated with nasal oxygen delivery in patients on long-term oxygen therapy (LTOT). In addition, TTOT improves compliance and quality of life, and may reduce morbidity. Experience with TTOT in Europe is, however, scarce and the safety of TTOT has not yet been completely determined. These were reasons for testing the acceptance, efficacy and safety of TTOT. Patients were selected on the basis of the accepted indications and contraindications for TTOT. In 75 patients (48 males and 27 females) the mean follow-up time was 16 (range 0.5-51.5) months. Compared to nasal cannulae, TTOT caused a reduction in the oxygen flow rate of 47 (33-60)% at rest and a significant increase in the number of hours that oxygen was used. All patients on TTOT used oxygen for at least 20 h x day(-1). Most patients saw the procedure as a minor intervention. It was usually performed on an out-patient basis. In 34 patients, 51 mainly minor complications were seen, and most of these occurred in the first 10 patients. After precautions had been taken, complications occurred less frequently. No patient needed to be hospitalized because of a complication. TTOT had to be stopped in two patients; nevertheless, all patients preferred TTOT to the nasal cannulae. We conclude that transtracheal oxygen therapy is an effective and safe alternative to nasal oxygen administration, provided that it is restricted to a well-defined group of patients and applied by a motivated and experienced group of physicians.

Learning cardiopulmonary resuscitation skills: does the type of mannequin make a difference?

Resuscitation (CPR) courses stress acquisition of psychomotor skills. The number of mannequins may limit the 'hands-on' time available for each trainee to practise CPR and impede acquisition of skill. This may occur because expensive, sophisticated mannequins are favoured over individual, simple mannequins. In a blind, prospective, controlled study we compared one-rescuer CPR skills of 165 trainees in two cohorts using their own individual light-weight torso mannequins (Actar 911 and Laerdal Little Anne) and a control cohort with four to five trainees sharing a sophisticated mannequin (Laerdal Recording Resusci Anne). No major significant differences (p = 0.18) were found when using the 'Berden scoring system'. Both the Actar 911 and the Little Anne were compatible with the Recording Resusci Anne. Trainees preferred the individual mannequins. We conclude that the results indicate that the use of individual mannequins in conjunction with a sophisticated mannequin neither results in trainees learning incorrect skills nor in significant improvement. Further analysis of the actual training in lay person CPR training courses and evaluation of course didactics to optimize training time appear indicated.

[Favorable results of nocturnal nasal positive-pressure ventilation in 64 patients with neuromuscular disorders; 5-year experience]. / Gunstige effecten van nachtelijke nasale positieve-drukbeademing bij 64 patiënten met neuromusculaire aandoeningen; 5 jaar ervaring.

OBJECTIVE: Evaluation of the effectiveness of chronic nightly mechanical ventilation through a nasal mask system in patients with neuromuscular diseases or patients with thorax malformations or COPD. SETTING: Centre for Home Mechanical Ventilation, University Hospital Utrecht. DESIGN: Retrospective study. METHOD: During the period June 1988-May 1993, 64 patients (11-69 years old) were treated with nasal mask ventilation during the night: 37 men (most of whom had Duchenne's disease (18) and 27 women (most of whom had (post-polio) kyphoscoliosis (n = 13). The effects on arterial blood gases were analysed. Complications during use of the nasal mask systems were recorded. RESULTS: The duration of the nasal mask ventilation was 2 to 56 months. Arterial PCO2 and PO2 improved during the night as well as by day during spontaneous respiration. The most common problems were necrosis of the skin of the bridge of the nose, leakage of air through the mouth or insufflation of air into the stomach. After the start of the mechanical ventilation quality of life improved considerably. CONCLUSION: Nasal ventilation at night is sufficient and simple. The installation of a tracheostoma can be postponed or avoided with this non-invasive kind of ventilation.

Long-term oxygen therapy.

This review discusses the different aspects of long-term oxygen therapy (LTOT). In selected patients with chronic hypoxaemia, LTOT may increase the life-span and quality of life. Since identification of these patients is both important and difficult, the indications for LTOT are discussed. Next, the appropriate time at which LTOT should be initiated is discussed in the section on the physiological criteria. Even in patients who qualify for LTOT, the effectiveness of this therapy may vary. Because they are important in this context, the prescription guidelines are considered. Finally, possible ways of increasing the efficiency of LTOT are reviewed in the sections on home oxygen systems, oxygen-conserving methods and the organization of LTOT in the Netherlands.

Comparison of effects of dopamine hydrochloride and dopexamine hydrochloride on abdominal and femoral hemodynamics in anesthetized dogs.

The effects of dopamine and dopexamine administered in graded intravenous bolus injections (0.1-51.2 micrograms.kg-1) were compared in the renal and femoral, and in a number of splanchnic vessels at the organ level simultaneously in anesthetized dogs. Hemodynamic data are presented for each artery as conductance, which was obtained by dividing mean flow by mean arterial pressure. The data were analyzed in two different ways: 1) by responses at intervals of 3 sec to 12.8 micrograms dopamine or dopexamine during 1 min, and 2) by dose-response curves. Additionally, urine volume was measured during dopamine and dopexamine administration. During a period of 1 min after an injection of dopamine, early and late effects could be distinguished, while heart rate was unaltered. In the superior mesenteric, inferior mesenteric, splenic, common hepatic, renal, and femoral arteries, an early (at 18-21 sec) reduction in conductance was seen. The early reduction was often followed by an increase above the preinjection level. After dopexamine, the early reduction in conductance was not seen, except in the left gastric artery. In contrast to the effect of dopamine, dopexamine induced a more pronounced increase during the late phase. Contrary to dopamine, dopexamine increased the conductance in the common hepatic artery bed. It remains questionable whether dopaminergic receptors are present in this vascular bed. Dopamine raised blood pressure and urine production dose-dependently. Dopexamine decreased aortic pressure. Low dosages of dopexamine increased urine production, without raising renal blood flow. An advantage of dopexamine over dopamine could be that dopexamine does not stimulate alpha-adrenergic receptors.