Carbon monoxide poisoning: a five year review at Tan Tock Seng Hospital, Singapore.

INTRODUCTION: Carbon monoxide poisoning (COP) is one of the leading causes of death from poisoning worldwide. There is no published study of COP in Singapore so far. MATERIALS AND METHODS: All patients admitted with the diagnosis of COP to Tan Tock Seng Hospital (TTSH) over 5 years from 1999 to 2003 were retrospectively reviewed. The diagnosis was based on a history of potential exposure to carbon monoxide (CO) and elevated levels of carboxyhaemoglobin (COHb). The causes, demographic data, clinical presentations, management and complications were analysed. RESULTS: There were 12 patients with COP. Their average age was 38.9 (+/-11.8) years, with a male-to-female ratio of 3:1. Accidental COP (58.3%) was more common than intentional COP (41.7%). The most common cause of accidental COP was smoke inhalation from a faulty vehicle. Gas stove was the most preferred source for intentional poisoning. Presenting features were headache (83.3%), confusion (83.3%), coma (12.7%) and agitation (8.3%). The mean COHb level on admission was 35.9% (+/-13.6). All were treated with 100% oxygen. All the patients achieved normal levels of COHb within 24 hours of admission. Two (16.7%) required intubation for airway protection as they were comatose on arrival, of which 1 presented with very high level of COHb (48.1%) and was the only patient to be treated with hyperbaric oxygen. Acute complications were globus pallidus infarction (16.6%), acute respiratory distress syndrome (8.3%) and myocardial ischaemia (8.3%). Most of the patients (91.7%) were discharged well from the hospital. One patient developed parkinsonism after a follow-up of 2 years. There were no deaths. CONCLUSION: COP is relatively uncommon in Singapore. It has a low rate of short- and long-term complications.

Severe adult chickenpox infection requiring intensive care.

INTRODUCTION: Chickenpox (varicella) in adults can be severe with increased mortality. This study investigated the clinical presentation and outcome of 12 adult chickenpox patients requiring intensive care. MATERIALS AND METHODS: A retrospective, observational study was performed in an adult medical intensive care unit of a university-affiliated hospital involving consecutive patients with varicella admitted over 4 years (1997-2000). RESULTS: The 12 patients had a mean +/- SD age of 40 +/- 20 (range, 15 to 86) years. Two patients were above 65 years old (aged 73 and 86 years). All but 1 were male. None had previous varicella vaccination. Six patients had direct exposure to persons with chickenpox infection. Four patients had underlying pulmonary pathology: past pulmonary tuberculosis (2), emphysema (1) and recurrent right pleural effusion from autoimmune serositis (1). The mean APACHE II score was 14.2 (range, 6 to 26). Ten patients had varicella pneumonia (of whom 2 had acute respiratory distress syndrome and 5 had acute lung injury), 1 had chickenpox encephalitis and 1 patient presented concomitantly with diabetic ketoacidosis. The median duration of stay in the intensive care unit (ICU) was 11 days (range, less than 1 day to 76 days). Nine patients (75%) required mechanical ventilation (median duration, 14 days; range, less than 1 day to 79 days). All patients were treated with acyclovir. There were 3 deaths (25%); 2 were above 65 years old and 1 was 37 years old with acute myeloid leukaemia on chemotherapy. CONCLUSION: Patients with varicella infection requiring intensive care carry significant mortality. In our series, old age appears to be associated with increased mortality (P = 0.045).

Is increasing age associated with mortality in the critically ill elderly.

INTRODUCTION: Age has been cited as a predictor of mortality in the intensive care unit (ICU) and suggested as a criterion for rationing resources. We investigated the association of age with both ICU mortality and hospital mortality. MATERIALS AND METHODS: Patients admitted in 1998 to our Medical ICU (MICU) were retrospectively analysed by stratifying them into four groups: the reference group (55-64 years), the young old (65-74 years), the old old (75-84 years) and the oldest old (more than 85 years). The statistical association of age with ICU mortality and total hospital mortality was determined whilst controlling for the APACHE II(M) score (APACHE II score modified to exclude points for age), the number of organ failures and the presence of a high risk admitting diagnosis. RESULTS: After controlling for disease severity, the ICU mortality and the total hospital mortality were not associated with age. The total hospital mortality was associated with the APACHE II(M) score (Odds ratio (OR), 1.08; 95% Confidence intervals (CI), 1.04-1.12), the number of organ failures (OR, 2.03; CI, 1.50-2.67) and the presence of a high risk diagnosis (OR, 3.50; CI 1.93-6.37). The ICU mortality was also associated with the APACHE II(M) score (OR, 1.07; CI, 1.03-1.11), the number of organ failures (OR, 1.63; CI, 1.26-2.09) and the presence of a high risk diagnosis (OR, 3.22; CI 1.81-5.76). CONCLUSIONS: We did not find a statistically significant association between age and mortality. We recommend that age should not be used as a criterion for admission.