The objective of the study was to evaluate the predictive value of pulse oximetry before treatment of acute asthma in the prehospital setting. Unfavorable outcome was defined as need for mechanical ventilation during the acute attack. The study was carried out prospectively. The patients were divided into two groups: SpO2 or = 80%. The study group consisted of 44 patients with 47 asthmatic attacks. Eleven patients had SpO2 or = 80%, none required mechanical ventilation. Oximetry before treatment with a cut off point of
To evaluate an ambulatory physiological monitoring system during a mountaineering expedition. We hypothesized that the Environmental Symptoms Questionnaire, combined with frequent measurement of oxygen saturation and core temperature, would accurately identify cases of environmental illness.
Twelve military mountaineers took a daily Environmental Symptoms Questionnaire, monitored fingertip oxygen saturations, and recorded core temperatures while climbing a 4,949-m peak. Illnesses identified by the system were compared with those identified by spontaneous reports.
The system correctly identified one case of high-altitude pulmonary edema and two illnesses that were not reported to the physician (one case of acute mountain sickness and one of self-limited symptomatic desaturation). However, it did not identify two illnesses that were severe enough to preclude further climbing (one case of sinus headache and one of generalized fatigue).
Our monitoring system may complement, but cannot replace, on-site medical personnel during mountaineering expeditions.
OBJECTIVES: The aim of the study was to assess the extent and quality of follow-up of patients on LTOT. SETTING: The Danish Oxygen Register. SUBJECTS: A total of 890 chronic obstructive pulmonary disease (COPD) patients who were on long-term oxygen therapy (LTOT) during the period from 1 November 1994 to 31 August 1995. MAIN OUTCOME MEASURES: The extent and quality of follow-up. RESULTS: Only 38.5% of the patients were followed up in the study period, and only 17.5% had a 'sufficient follow-up' defined as at least one follow-up visit within 10 months which included measurement of arterial blood gases or pulsoximetry with oxygen supply, verification that the patient used oxygen > or =15 h day-1 and was nonsmoker. Female gender, LTOT initiated 3-12 months ago, LTOT started by a chest physician at pulmonary department and LTOT prescribed > or =15 h day-1 were found to be significant predictors of 'sufficient follow-up' (odds ratio (OR): 1.7, 2.0, 3.7 and 1.9, respectively). CONCLUSIONS: The extent and the quality of follow-up of patients on LTOT were poor, especially if a nonpulmonary physician initiated LTOT. We recommend that more attention should be paid on proper monitoring of LTOT, and that only chest physicians should be able to prescribe and re-evaluate LTOT.
Pulse oximetry (PO) was applied to 79 otherwise healthy children during and after minor ENT surgery under general anaesthesia in private practice. The PO data were not available to the anaesthetist unless desaturation to less than or equal to 85% was present for greater than or equal to 30 s. This occurred in 12 and 9 cases during anaesthesia and recovery, respectively, only 8 and 5 cases, respectively, being diagnosed clinically. Desaturation during and after anaesthesia was more common in children undergoing adenoidectomy than during procedures for which endotracheal intubation was not performed. During recovery, desaturation was more likely to occur in the same patients again. Lower values of SaO2 were found in younger children and in children resisting or crying at induction. There was a (weak) negative correlation between SaO2 and HR. As clinically undiagnosed desaturation occurs even in healthy children undergoing minor surgical procedures, a more widespread use of PO during and after anaesthesia may be advisable.
Insufficient vascularisation of substitutes in the operative reconstruction of the oesophagus is one of the main causes of the occurrence of anastomotic leaks. In the present study, the blood oxygenation of gastric substitutes for the oesophagus was evaluated before and during the reconstruction. A pulse oximeter was used for the assessment (S&J Medico Teknik AIS, Albertslund, Denmark). Oxygenation in the examined places ranged from 79% to 98%. The values of blood oxygenation in places C1 (fundus of the stomach after the formation of the substitute) and C2 (fundus of the stomach after the formation and stretching of the substitute) were significantly lower than those in analogous places in the stomach before the transformation (C/C1 p
In coronary artery disease (CAD), exercise intolerance with reduced oxygen uptake at peak exercise (VO2peak) is assumed to primarily reflect cardiovascular limitation. However, oxygen transport and utilization depends on an integrated organ response, to which the normal pulmonary system may influence overall capacity. This study aimed to investigate the associations between normal values of lung function measures and VO2peak in patients with exercise intolerance and CAD. We hypothesized that forced expiratory lung volume in one second (FEV1), transfer factor of the lung for carbon monoxide (TLCO) and TLCO/alveolar volume (TLCO/VA) above lower limits of normal (LLN) are associated with VO2peak in these patients. We assessed patients with established CAD (n = 93; 21 women) referred for evaluation due to exercise intolerance from primary care to a private specialist clinic in Norway. Lung function tests and cardiopulmonary exercise testing (CPET) were performed. Z-scores of FEV1, FEV1/forced vital capacity (FVC), TLCO and TLCO/VA were calculated using the Global Lung Function Initiative (GLI) software and LLN was defined as the fifth percentile (z = -1.645). Non-obstructive patients, defined by both FEV1 and FEV1/FVC above LLN, were assessed. The associations of FEV1Z-score, TLCOZ-score and TLCO/VAZ-score above LLN with VO2peak were investigated using linear regression models. Mean VO2peak ± standard deviation (SD) was 23.8 ± 6.4 ml/kg/min in men and 19.7 ± 4.4 ml/kg/min in women. On average, one SD increase in FEV1, TLCO and TLCO/VA were associated with 1.4 (95% CI 0.2, 2.6), 2.6 (95% CI 1.2, 4.0) and 1.3 (95% CI 0.2, 2.5) ml/kg/min higher VO2peak, respectively. In non-obstructive patients with exercise intolerance and CAD, FEV1, TLCO and TLCO/VA above LLN are positively associated with VO2peak. This may imply a clinically significant influence of normal lung function on exercise capacity in these patients.
Eisenmenger's syndrome (ES) is the most advanced form of pulmonary arterial hypertension related to congenital heart disease. Evolution of pulmonary vascular disease differs markedly between patients with atrial septal defects (ASD) versus ventricular septal defects (VSD), potentially affecting response to treatment. We compared the effects of bosentan and placebo in patients with isolated ASD (ASD subgroup) versus patients with isolated VSD or both defects (VSD subgroup).
Post-hoc analysis of a 16-week, multicenter, randomized, double-blind, placebo-controlled trial was performed. Fifty-four patients (13: ASDs, 36: VSDs, 5: VSD+ASD) were randomized to bosentan 62.5 mg bid for four weeks (uptitrated to 125 mg bid thereafter) or placebo. Main outcome measures were: indexed pulmonary vascular resistance (PVRi), exercise capacity, mean pulmonary artery pressure (mPAP), pulmonary blood flow index (Qpi), and changes in oxygen saturation (SpO2).
Placebo-corrected median (95% CI) treatment effects on PVRi were -544.0 dyn·s·cm?5 (-1593.8, 344.7) and -436.4 dyn·s·cm?5 (-960.0, 167.0) in the ASD and VSD subgroups, respectively. Effects of bosentan on exercise capacity and mPAP were similar in both subgroups. No changes in SpO2 or Qpi were observed in either bosentan or placebo subgroups.
Improvements in exercise capacity and cardiopulmonary hemodynamics, without desaturation, were observed in ES patients with both ASDs and VSDs. Although not reaching statistical significance, improvements were similar to those in the BREATHE-5 analyses, suggesting that the location of septal defects is not a key determinant of treatment response. These data further support the use of bosentan for the treatment of ES, independent of shunt location.
Obstructive sleep apnea (OSA) is related to postoperative complications and is a common disorder. Most patients with sleep apnea are, however, undiagnosed, and there is a need for simple screening tools. We aimed to investigate whether STOP-Bang and oxygen desaturation index can identify subjects with OSA.
In this prospective, observational multicenter trial, 449 adult patients referred to a sleep clinic for evaluation of OSA were investigated with ambulatory polygraphy, including pulse oximetry and the STOP-Bang questionnaire in 4 Swedish centers. The STOP-Bang score is the sum of 8 positive answers to Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index >35 kg/m, Age >50 years, Neck circumference >40 cm, and male Gender.
The optimal STOP-Bang cutoff score was 6 for moderate and severe sleep apnea, defined as apnea-hypopnea index (AHI) =15, and the sensitivity and specificity for this score were 63% (95% CI, 0.55-0.70) and 69% (95% CI, 0.64-0.75), respectively. A STOP-Bang score of 15 and a STOP-Bang score of =6 had a specificity of 91% (95% CI, 0.87-0.94) for an AHI >15. The items contributing most to the STOP-Bang were the Bang items. There was a positive correlation between AHI versus STOP-Bang and between AHI versus oxygen desaturation index, Spearman ? 0.50 (95% CI, 0.43-0.58) and 0.96 (95% CI, 0.94-0.97), respectively.
STOP-Bang and pulse oximetry can be used to screen for sleep apnea. A STOP-Bang score of
Polysomnography is the best tool available for diagnosing obstructive sleep apnea (OSA) in children. However, polysomnography is relatively inaccessible and costly, and studies are needed to evaluate other diagnostic approaches. It has been suggested that the OSA-18 quality-of-life questionnaire (OSA-18) is a useful measure that could replace polysomnography. The purpose of our study was to determine if the OSA-18, is an accurate measure for the detection of moderate-to-severe OSA.
Children who were referred to our sleep laboratory for evaluation of suspected OSA and who had a nocturnal pulse oximetry study were included in our cross-sectional study. The results of the oximetry study were interpreted by using the McGill oximetry score (MOS). Abnormal scores were consistent with moderate-to-severe OSA. We analyzed demographic and medical data in addition to the OSA-18 results. We estimated sensitivity and negative predictive values for the OSA-18 to detect an abnormal MOS. We also conducted logistic regression analyses with MOS as the dependent variable and the OSA-18 score, age, gender, comorbidities, and race as independent variables.
We studied 334 children (mean age: 4.6 years; 58% male). The OSA-18 had a sensitivity of 40% and a negative predictive value of 73% for detecting an abnormal MOS. While controlling for other variables in the regression model, for each unit increase in the OSA-18 score, the odds of having an abnormal MOS were increased by 2%. For each 1-year increase in age, the odds of having an abnormal MOS were decreased by 17%.
Among children who are referred to a sleep laboratory, the OSA-18 does not accurately detect which children will have an abnormal MOS and cannot be used to exclude moderate-to-severe OSA. The OSA-18 should not be used in the place of objective testing to identify moderate-to-severe OSA in children.