Event-related evoked potentials in chronic respiratory encephalopathy.

BACKGROUND: Cognitive event-related potential (P(300)) is an index of cognitive processing time. It was found to be prolonged in dementia, renal, and hepatic encephalopathies, but was not extensively assessed in respiratory failure. OBJECTIVE: To evaluate P(300) changes in patients with respiratory failure, and especially those with mild or subclinical hypoxic-hypercapnic encephalopathy. METHODS: Auditory event-related evoked potential P(300) latency was measured using an oddball paradigm in patients with respiratory failure due to any cause (partial pressure of oxygen in arterial blood (PO(2)) should be 75 mm/Hg or less). Apart from blood gases measurement, patients underwent the Mini-Mental State Examination (MMSE). Patient performances were compared with that of matched normal control. Patients were admitted into the study from outpatient clinics and wards at King Khalid University Hospital and Sahara Hospital. RESULTS: Thirty-four patients (12 women, 22 men) were admitted to the study. Ages ranged from 19-67 years with a mean of 46.1 years. Respiratory failure was severe or very severe in 11 patients (33%), and mild or moderate in the rest (66%). Mean value for PO(2) and partial pressure of carbon dioxide in arterial blood (PCO(2)) were 63.7 and 45.2 mm/Hg, respectively. pH mean was 7.4 and O(2) saturation was 90.7%. P(300) latency ranged from 218 to 393 milliseconds, with a mean of 338.4 milliseconds. In comparison with control (309.9 milliseconds), there was a significant difference (P = 0.007). P(300) amplitude differences were not significant. No significant difference in MMSE was noted between mild and severe respiratory failure. Results of detailed neuropsychological assessment were clearly abnormal but were limited by the small number of tested patients. P(300) latency changes correlated significantly with age as well as severity of respiratory failure. P(300) was also significantly delayed whether hypoxia occurred with or without hypercapnia. CONCLUSION: Results show a significant delay of P(300) latency in patients with severe and mild respiratory failure. This was associated with subclinical encephalopathy in most patients, evidenced by a near-normal MMSE score. Apart from confirming the importance of P(300) latency measurement as a marker of respiratory encephalopathy, this study asserts the causal relationship between hypoxemia and cognitive derangement. Furthermore, it promotes the early use of oxygen therapy in a selected group of patients with mild or moderate respiratory failure, who have responsibilities which involve taking rapid critical decisions.

Information disclosure and decision-making: the Middle East versus the Far East and the West.

OBJECTIVES: to assess physicians' and patients' views in Saudi Arabia (KSA) towards involving the patient versus the family in the process of diagnosis disclosure and decision-making, and to compare them with views from the USA and Japan. DESIGN: A self-completion questionnaire (used previously to study these issues in Japan and the USA) was translated to Arabic and validated. PARTICIPANTS: Physicians (n = 321) from different specialties and ranks and patients (n = 264) in a hospital or attending outpatient clinics from 6 different regions in KSA. RESULTS: In the case of a patient with incurable cancer, 67% of doctors and 51% of patients indicated that they would inform the patient in preference to the family of the diagnosis (p = 0.001). Assuming the family already knew, 56% of doctors and 49% of patients would tell the patient even if family objected (p NS). However, in the case of HIV infection, 59% of physicians and 81% of patients would inform the family about HIV status without the patient's consent (p = 0.001). With regards to withholding ventilatory support, about 50% of doctors and over 60% of patients supported the use of mechanical ventilation in a patient with advanced cancer, regardless of the wishes of the patient or the family. Finally, the majority of doctors and patients (>85%) were against assisted suicide. CONCLUSIONS: Although there was more recognition for a patient's autonomy amongst physicians, most patients preferred a family centred model of care. Views towards information disclosure were midway between those of the USA and Japan. Distinctively, however, decisions regarding life prolonging therapy and assisted suicide were not influenced to a great extent by wishes of the patient or family, but more likely by religious beliefs.

Behaviour and time-course of sleep disordered breathing in patients with acute coronary syndromes.

To our knowledge, no study has examined the persistence of sleep disordered breathing in acute coronary syndrome (ACS) patients. We examined the time course of SDB in ACS patients by assessing them within days of the acute event and again after 6 months. Consecutive patients with ACS were asked to voluntarily participate in the study. Patients underwent an overnight polysomnography (PSG) approximately 3 days after the acute event. Patients with an apnea hypopnea index (AHI) > 10/h then underwent another PSG after they were stable (approximately 6 months). Fifty patients were studied. First PSG showed an AHI was 23.1 +/- 3.6/h. A second PSG was performed 6.1 +/- 0.3 months later on 21 patients and showed an AHI > 10/h in the first assessment. The AHI and the obstructive apnea index did not change over the 6 months. However, the central apnea index all was lower at the second assessment.

Azithromycin in bronchiolitis obliterans complicating bone marrow transplantation: a preliminary study.

Bronchiolitis obliterans (BO) is a serious noninfectious pulmonary complication following allogeneic bone marrow transplantation (BMT). Azithromycin, a macrolide antibiotic, may have a beneficial effect in BO through its anti-inflammatory effect. The aim of the current study was to investigate the potential effect of azithromycin on pulmonary function tests (PFTs) in BO complicating BMT. PFTs of 153 post-BMT patients were followed; eight patients out of 153 (12%) developed obstructive airway disease on their PFTs, along with characteristic findings of BO on high-resolution computed tomography of the chest. These patients were given azithromycin 500 mg q.d. for 3 days, followed by 250 mg three times a week for 12 weeks. Clinically significant improvements were achieved both in forced vital capacity, where the mean (95% confidence interval) increase reported was 410 mL (0.16-0.65), which was an average improvement of 21.57%, and in the forced expiratory volume in one second, where the mean increase noticed was 280 mL (0.10-0.44), which was an average improvement of 20.58%. In conclusion, the potential role of azithromycin in the treatment of bronchiolitis obliterans is intriguing and it warrants further testing.

Should oxygen saturation be included in the vital signs sheet of all medical admissions?

Hypoxaemia is not uncommon in hospitalised patients and may be overlooked because cyanosis is a late sign. To estimate the incidence of undetected hypoxaemia we measured oxygen saturation (SpO2) by pulse oximetry randomly in medical patients who were not receiving supplemental oxygen in a teaching hospital and a community hospital. Of 580 patients studied, nine patients (1.55%) had SpO2 <92%. All nine patients had multiple morbidities, but all had cardiopulmonary disease in common. There was no significant difference between the teaching and the community hospitals. We conclude that undetected hypoxaemia is not common in patients on the medical wards, and that routine pulse oximetry is not necessary except for patients with known cardiopulmonary disease.

A patient with hypoxemia and a normal chest radiograph.

The case of a young patient with hypoxemia and a normal chest radiograph is presented in the form of a clinical quiz, followed by a discussion of the differential diagnosis, investigative methods and a brief review of the final diagnosis.

Allergic bronchopulmonary mycosis in patients with asthma: period prevalence at a university hospital in Saudi Arabia.

Allergic bronchopulmonary mycosis (ABPM) is a known complication of asthma and can result in progressive lung damage, respiratory failure and death. Asthma is a common disease in Saudi Arabia and until now the prevalence of ABPM has not been investigated. The aim of this study was to estimate the period prevalence of ABPM due to Aspergillus and Candida in patients with asthma. The setting was an outpatient pulmonary clinic at a university hospital in the central region of Saudi Arabia. Two hundred and sixty-four consecutive patients with asthma (150 or 57% females) were evaluated. All patients were screened for ABPM with skin prick test (SPT) using a panel of fungal antigens. Those with positive skin reactions had further clinical, immunological, respiratory and radiological assessment. ABPM was diagnosed by the presence of a minimum of five of the major criteria suggested by Rosenberg in 1977. Of the 264 patients, 62 (23%) had a positive SPT for at least one fungal allergen, of whom 44 (71%) were females (P=0.01). Seven patients (six females) were diagnosed with ABPM due to Aspergillus and (or) Candida species. Therefore, we estimate the period prevalence of ABPM to be 2.7% (95% confidence interval 1.3-5.4%). A. niger was the commonest fungal species isolated in our group. In conclusion, ABPM is not uncommon in Saudi Arabia and females seem to be more at risk. Because asthma is common, physicians need to have high index of suspicion for this disease and pursue the diagnosis with the appropriate tests.

Progressive rise of Mycobacterium tuberculosis resistance to rifampicin and streptomycin in Riyadh, Saudi Arabia.

OBJECTIVE: The aim of this study was to investigate, for the first time, the factors associated with resistance to antituberculous drugs in Saudi Arabia, and to follow the long-term trends in drug resistance. METHODOLOGY: A retrospective study of patients with positive Mycobacterium tuberculosis recorded at the Riyadh Tuberculosis Center in 1990 was undertaken. The resistance figures from the same centre for the period July 1996 to June 1997 were reviewed for comparison. RESULTS: Resistance was significantly higher in those previously treated (71%) than in those who denied previous treatment (34%). There was a trend towards association of resistance with cavitatory, multilobar, and acid fast bacilli-positive cases. Nationality (Saudis, Yemenis, others) had no significant effect on resistance. The Riyadh Region now has the same high prevalence of rifampicin resistance as previously reported in the Western Region of the Kingdom. The figures on resistance for the years 1986-88, 1990, and 1996-97 were: isoniazid 19.5/13.8/11.1%, rifampicin 10/20.7/24.6%, streptomycin 5/22/27.4%, ethambutol 3.7/3.9/1.8%, respectively. The reduction in isoniazid and ethambutol resistance coincided with a rise in resistance to rifampicin and streptomycin. We speculate that this resulted from the fact that isoniazid and ethambutol are restricted only to the treatment of tuberculosis and cannot, by law, be dispensed by general practitioners or private pharmacies. Rifampicin and streptomycin, however, are widely used for brucellosis; an endemic disease in Saudi Arabia where up to 12 weeks of rifampicin therapy is recommended. CONCLUSIONS: There has been a significant increase in rifampicin and streptomycin resistance in Saudi Arabia over the last 10 years. Possible causes include poor compliance and wide use of these two drugs for non-tuberculosis conditions. These findings could jeopardize the benefits of the directly observed therapy short course policy which is being implemented in Saudi Arabia. Consideration should be given to prohibiting the routine use of rifampicin for the treatment of brucellosis.

Physicians' attitudes towards 'do-not-resuscitate' orders for the elderly: a survey in Saudi Arabia.

To study physicians' attitudes towards do-not-resuscitate orders (DNR) in the elderly and analyze the responses to some of the factors that may influence the resuscitation decisions, a self-completed questionnaire was administered to physicians in the departments of Medicine and Critical Care in three cities in Saudi Arabia. Physicians were asked whether they would recommend DNR for two hypothetical cases, one elderly and previously functional and another younger patient suffering from severe dementia. They were asked also to grade the importance of a number of factors that may have some influence on the resuscitation decisions. A total of 249 physicians participated in the study (a response rate of 79%). Only 16% of physicians indicated they would recommend DNR for the previously healthy elderly as opposed to 61% for the patient with dementia (P<0.001). When considering DNR orders, physicians ranked dignity of the patient, religious and legal concerns highly, and cared least about expenses of the medical care. In conclusion, most physicians assigned more importance to the functional status of the patient than the biological age. When considering DNR, physicians in Saudi Arabia shared with their counterparts in the West many features, notably caring about dignity of the patient, but were also concerned about the religious and the legal stand. This may be related to the absence of clear local policies and guidelines.

Clinical profile of sleep apnea syndrome. A study at a university hospital.

OBJECTIVES: To review a series of patients with sleep apnea syndrome, to promote more awareness and alert local health professionals to early diagnosis and treatment. METHODS: We studied, prospectively, 48 consecutive patients who were managed at the university hospital from 1992 to 1996. RESULTS: The male:female ratio was 1.4:1. The mean interval between onset of symptoms and the diagnosis was 5.5 years (range 0.25 to 30). In over half of the patients the diagnosis was not suspected upon referral. The mean body mass index was 42.8 kg/m2, (range 25 to 76). Daytime hypoxemia was present in 28 patients (58%), while 26 (54%) had Pa CO2 > 45 mmHg, mainly as a result of obesity-hypoventilation syndrome. Significant proportions had systemic and pulmonary hypertension (60% and 23%), and 32% had ischemic heart disease. All patients, but one, tolerated continuous positive airway pressure, but cost of the equipment led some to prefer surgical treatment that is offered free. CONCLUSION: This series shows a bias towards female sex and frequent association with obesity-hypoventilation syndrome. In many cases the diagnosis was not suspected suggesting poor recognition and awareness of sleep apnea syndrome. Monitoring pulse oximetry during sleep was helpful in the diagnosis and titration of continuous positive airway pressure. Ways of providing continuous positive airway pressure under the health system need to be studied.

Tuberculosis simulating malignancy.

Full text is available as a scanned copy of the original print version.

Allergic bronchopulmonary aspergillosis: disease pattern in central Arabia.

Despite a high prevalence of asthma in Saudi Arabia, allergic bronchopulmonary aspergillosis (ABPA) has not been reported. We reviewed the medical records in a large university hospital in Saudi Arabia where thousands of asthmatics are being followed up. Over a 9-year period starting January 1986, the diagnosis of ABPA was made in 10 patients only. Delay in diagnosis was common and in some patients the disease was confused with fungal pneumonia, tuberculosis or tumours. Aspergillus fumigatus was isolated from one patient only and different Aspergillus species were cultured from respiratory secretions of the others. Corticosteroids were uniformly effective in all patients with active disease. Low humidity may account for this apparent rarity of ABPA, although it is possible that some cases are overlooked. Further work is needed on the prevalent fungi in the Arabian environment and their potential health effects and particularly on the prevalence of allergic bronchopulmonary fungal disease.

Management of interstitial lung disease: an audit at a university teaching hospital in Saudi Arabia.

To assess the management of interstitial lung disease (ILD) in relation to the published guidelines 122 consecutive cases were analyzed. Clinical features and non-invasive laboratory tests led to the diagnosis in nearly one sixth of the patients (16%), mainly CTD and a few miscellaneous disorders. In another sixth the diagnosis was reached by means of a transbronchial lung biopsy, particularly in sarcoidosis. Nearly a third had surgical lung biopsies, which were diagnostic in 98%. The diagnoses were reached in 82 patients (67%) and include: cryptogenic fibrosing alveolitis (20), sarcoidosis (16), connective tissue disease (17) and miscellaneous (29). The remaining third were undiagnosed, and this group had a higher mean age and was much less likely to receive immunosuppressive therapy than any group with a specific diagnosis. It is concluded that while physicians reached a specific diagnosis in most cases of ILD, commonly through a lung biopsy. A sizeable proportion (nearly a third), or remained undiagnosed and those were less likely to be treated and had a poorer prognosis. The availability of less invasive techniques should encourage physicians to obtain a biopsy since this is likely to lead to a more active approach to therapy.