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PubMed2005

Evaluation of the A&D UA-767 and Welch Allyn Spot Vital Signs noninvasive blood pressure monitors using a blood pressure simulator.

The performance of five units of the A&D UA-767 NIBP monitor and five units of the Welch Allyn Spot Vital Signs noninvasive blood pressure monitor was evaluated with the Biotek BP Pump blood pressure simulator under a variety of conditions. Using the simulator to provide a normal blood pressure waveform at 80 bpm over a range of pressures, it was found that the mean bias for the combined results from the A&D monitors was 1.9+/-2.8 mmHg and from the Welch Allyn monitors was 0.7+/-2.4 mmHg. No individual measurement showed a bias greater than 10 mmHg. A bias of greater than 5 mmHg was present in 28 out of 150 measurements for the A&D monitor and 10 out of 150 measurements for the Welch Allyn monitor. These results are comparable with ratings achieved by the instruments when tested previously according to the British Hypertension Society protocol, but testing with a simulator allowed assessment of aspects of performance which were not included in the British Hypertension Society protocol.

Artifacts↗
PubMed2002

Effect of home monitoring on a high-risk population.

A large cohort of infants (8,998) at high risk for sudden and unexpected death was followed with home cardiorespiratory monitoring over a five-year period. These infants included premature infants (23-36 weeks post-conceptual age), SIDS siblings, and infants who experienced an Apparent Life-Threatening Event. The overall SIDS rate in this high-risk population was 0.55/1,000, a rate significantly less than the 0.85 deaths/1,000 reported in the "general population" of Georgia over this same time period. In addition, we report our experience with using home monitors as a diagnostic tool, as well as how monitors can actually be cost-effective. Editorial opinions, and lay press summaries of the CHIME study (JAMA, May 2, 2001) imply that home cardiorespirtory monitors are of little value. Despite the fact that the study never made this claim, many clinicians are now referring to this study as evidence that home monitoring is ineffective and not needed. This article disputes those misconceptions about home cardiorespiratory monitors based on our experience with a large high-risk population of infants.

Equipment Safety↗
PubMed2002

A highly sensitive hexachromium monitor using water core optical fiber with UV LED.

A simply structured, cheap hexachromium monitor was developed. The monitor is based on UV/VIS absorption technique. A 2-m long water core optical fiber was employed as a long path length sample cell and a UV light emitting diode (LED) was used as a light source. The emission profile of the UV LED fits very well with the absorption spectrum of chromate ions in water. Therefore, the light-dispersing element, which is usually used in an optical spectrometer, is not necessary in this monitor design. The water core fiber as a long path length makes the monitor highly sensitive for hexachromium detection. This monitor is specific for hexachromium detection without interference from tri-valence chromium ions. A detection limit of 0.1 ng Cr(VI) ml(-1) was obtained with this simple monitor.

Adsorption↗
PubMed2004

Requirements for developing a regional monitoring capacity for aerosols in Europe within EMEP.

The European Monitoring and Evaluation Programme (EMEP) has been established to provide information to Parties to the Convention on Long Range Transboundary Air Pollution on deposition and concentration of air pollutants, as well as on the quantity and significance of long-range transmission of pollutants and transboundary fluxes. To achieve its objectives with the required scientific credibility and technical underpinning, a close integration of the programme's main elements is performed. These elements are emission inventories, chemical transport modelling, and the monitoring of atmospheric chemistry and deposition fluxes, which further are integrated towards abatement policy development. A critical element is the air pollution monitoring that is performed across Europe with a focus not only on health effect aspects and compliance monitoring, but also on process studies and source receptor relationships. Without a strong observational basis a predictive modelling capacity cannot be developed and validated. Thus the modelling success strongly depends on the quality and quantity of available observations. Particulate matter (PM) is a relatively recent addition to the EMEP monitoring programme, and the network for PM mass observations is still evolving. This article presents the current status of EMEP aerosol observations, followed by a critical evaluation in view of EMEP's main objectives and its model development requirements. Specific recommendations are given for improving the PM monitoring programme within EMEP.

Aerosols↗
PubMed2001

Monitoring in neuroanaesthesia: update of clinical usefulness.

The aim of specific monitoring in neuroanaesthesia is to detect, as quickly as possible, intraoperative ischaemic insults so that the brain and the spinal cord may be protected from harmful and frequently inevitable events due to the type of surgery, patient positioning, haemodynamic changes or any intercurrent event. New monitors are being introduced into the operating theatre, but only a few are considered to be an absolute standard of care in neurosurgery, e.g. facial nerve monitoring for surgery of acoustic neuromas and recording of evoked potentials during repair of scoliosis. In the past decade, new monitoring devices have moved from the experimental stage to the operating theatre and although most are still in a phase of technological development and/or definition of their field of applicability they are being used as guides for clinical practice in those instances where cerebral well-being might be impaired. The metabolic consequences of hyperventilation, pharmacological electroencephalogram burst suppression, hypothermia, etc. can now be assessed in the operating theatre. Non-invasive monitoring is being rapidly integrated into our daily work because of its lack of secondary effects. Nevertheless, each new development is regarded as an addition rather than as a substitute for existing equipment. The perfect combination of monitors to provide essential information during an individual surgical procedure to influence a better patient outcome, is still uncertain and needs extensive clinical research.

Anesthesia↗
PubMed2000

Aminoglycoside usage and monitoring in a Saudi Arabian teaching hospital: a ten-year laboratory audit.

BACKGROUND AND OBJECTIVE: In 1989, a therapeutic drug monitoring service was established in Assir Central Hospital, Abha, Saudi Arabia, by the Department of Clinical Pharmacology and Therapeutics of the College of Medicine, King Saud University Abha Branch (now King Khalid University). We report a 10-year follow-up of the results of monitoring the commonly used aminoglycosides (amikacin, gentamycin and tobramycin) obtained from our adult patients on first monitoring. METHOD: Two educational seminars for doctors and nurses were conducted 6 months before the initiation of this study. Drug assay requests were made on specially designed forms. Drug dosages were determined by the attending physicians. Samples for peak and trough drug level determinations were drawn after the fourth dose. The results of first time monitoring were sent to the wards with appropriate comments for dosage modifications where indicated. RESULTS: The results for 2022 patients were analysed. Of these, 929, 899 and 194 were for amikacin, gentamycin and tobramycin, respectively. Therapeutic trough concentrations were 71.2%, 28.3% and 28.3% of patients on amikacin, gentamycin and tobramycin, respectively. A total of 8.8%, 17.6% and 11.9% had trough concentrations considered toxic for amikacin, gentamycin and tobramycin, respectively. Peak therapeutic concentrations were achieved in 31.6%, 42.3% and 39.7% of patients on amikacin, gentamycin and tobramycin. A total of 53.3% of patients on amikacin, 50.3% on gentamycin and 57.2% on tobramycin had peak serum drug concentrations in the subtherapeutic range. Toxic concentrations were noticed mainly in patients aged over 60 years and in the critically ill in the intensive care, coronary care and bums units of the hospital. CONCLUSION: To be cost-effective, intensive therapeutic monitoring of aminoglycosides in adults should continue to be monitored mainly for the old and sick patients in critical care units to optimize patient management.

Adult↗
PubMed2004

Continuous ST-segment monitoring of patients with left bundle branch block and suspicion of acute myocardial infarction.

OBJECTIVES: Patients with left bundle branch block comprise 5-9% of all patients with acute myocardial infarction. Limited data exist on the usefulness of continuous electrocardiographic monitoring of these patients. We have investigated prospectively the usefulness of real-time continuous vectorcardiography for monitoring patients with left bundle branch block and suspicion of acute myocardial infarction. DESIGN: A prospective multi-centre study. SETTING: Fourteen Swedish coronary care units. SUBJECTS: Patients with left bundle branch block and suspicion of acute myocardial infarction with <6-h symptom duration were included. MAIN OUTCOME MEASURES: All patients were monitored with continuous vectorcardiography for 12-24 h. RESULTS: One hundred thirty-three patients were included, 47% had acute myocardial infarction. Patients with acute myocardial infarction showed a marked relative decrease in ST-vector than those without (P = 0.0002). These changes were most marked in the first 90 min. When comparing patients with acute myocardial infarction receiving thrombolytic therapy or not, those treated with thrombolytics showed more marked decline in ST-vector magnitude (P < 0.0001) and in shorter time (P = 0.0017). All patients showed STC-vector magnitude changes that were more marked in patients with acute myocardial infarction (P = 0.0002). An STC-vector magnitude cut-off value of 65 microV after 90 min of monitoring gave 54% sensitivity and 72% specificity for diagnosis of acute myocardial infarction. CONCLUSION: Real-time continuous vectorcardiographic monitoring of patients with left bundle branch and suspicion of acute myocardial infarction shows significant differences between those with and without acute myocardial infarction and could be of use for early diagnosis and subsequent monitoring.

Aged↗
PubMed2000

Oesophageal pH monitoring in infants: elimination of gastric buffering does not modify reflux index.

BACKGROUND: Oesophageal pH monitoring is considered to be the gold standard investigation in the diagnosis of gastro-oesophageal reflux disease. Results of pH monitoring in regurgitating infants, however, may be within normal ranges. Therefore it was hypothesized that prolonged buffering of gastric acidity caused by milk-feeding may falsely normalize the pH data. Therefore, it may be relevant to omit the periods of gastric acid buffering in the analysis of the oesophageal pH monitoring data. METHODS: Combined gastric and oesophageal pH monitoring (Digitrapper Mark III, two-channel antimony electrode, Synectics) was performed in 90 consecutive infants, 0.5-10 months old, who were referred to the unit by outdoor paediatricians for pH measurement. The data were analysed in three different ways. The reflux index (RI), or the percentage time that the pH in the oesophagus was < 4.0, was calculated in three different ways: (i) the total duration of the investigation; (ii) excluding 90-min postprandial periods, starting from the beginning of a feeding; and (iii) excluding all periods with a gastric pH > 4.0, which are the periods of gastric buffering with a theoretical impossibility of recording an oesophageal pH < 4.0. RESULTS: The mean duration of the pHmetries was 19.20+/-2.01h (A; mean +/- 1 SD), with a RI of 5.38+/-5.39% (B; median 3.45%). If the 90-min postprandial periods were not considered, the mean duration decreased to 12.21+/-2.41h (C; P(A vs C) < 0.001), with an oesophageal RI of 6.82+/-6.57% (D; median: 4.65; P(B vs D) = NS; r (B vs D) = 0.97). If all periods with a gastric pH > 4.0 were elminated, the duration available for analysis of the data with a gastric pH < 4.0 was 12.53+/-4.00 h (E; P(A vs E) < 0.001; P(C vs E) = NS), with an oesophageal RI of 7.06+/-7.52% (F; median: 4.50; P(B vs D vs F) = NS; r(B vs F), (D vs F) = 0.96). CONCLUSION: Overall the data do not support a benefit from including periods of gastric buffering in the routine analysis of oesophageal pH monitoring data. Therefore standard oesophageal pH monitoring should be with a single electrode and should not include periods of gastric buffering.

Cisapride↗
PubMed2003

Continuous glucose monitoring for treatment adjustment in diabetic pregnancies--a pilot study.

AIMS: To examine the efficacy of a continuous glucose monitoring (CGM) system for treatment adjustment in patients with diabetic pregnancy treated with insulin. METHODS: The study sample consisted of eight women with diabetic pregnancy, six with pre-pregnancy Type 1 diabetes mellitus and two with gestational diabetes (GDM), all being treated with multiple daily insulin injections. Gestational age ranged from 24 to 32 weeks. Data derived from the Continuous Glucose Monitoring System (MiniMed) for 72 h were compared with fingerstick glucose measurements (six to eight times a day), and treatment was adjusted on the basis of the findings. Two to four weeks later, the patients were re-evaluated with CGM. RESULTS: In the first part of the study, an average of 744+/-33 glucose measurements was recorded for each patient with CGM. The mean total time of hyperglycaemia (glucose level >7.7 mmol/l) undetected by the fingerstick method was 152+/-33 min/day. Nocturnal hypoglycaemic events (glucose level <2.7 mmol/l) were recorded in seven patients. Based on the additional information obtained by continuous monitoring, the insulin regimen was changed in all patients. CGM re-evaluation after treatment adjustment showed a reduction in undetected hyperglycaemia to 89+/-17 min/day and in nocturnal hypoglycaemic events, which were recorded in only one patient. CONCLUSIONS: Continuous glucose monitoring may diagnose high blood glucose levels and nocturnal hypoglycaemic events that are unrecognized by intermittent blood glucose monitoring and could serve as a useful tool for the long-term management of diabetic pregnancies. A large prospective study is needed to determine the clinical implications of this new monitoring technique.

Adult↗
PubMed2002

Continuous EEG monitoring in the intensive care unit.

Continuous EEG (CEEG) monitoring allows uninterrupted assessment of cerebral cortical activity with good spatial resolution and excellent temporal resolution. Thus, this procedure provides a means of constantly assessing brain function in critically ill obtunded and comatose patients. Recent advances in digital EEG acquisition, storage, quantitative analysis, and transmission have made CEEG monitoring in the intensive care unit (ICU) technically feasible and useful. This article summarizes the indications and methodology of CEEG monitoring in the ICU, and discusses the role of some quantitative EEG analysis techniques in near real-time remote observation of CEEG recordings. Clinical examples of CEEG use, including monitoring of status epilepticus, assessment of ongoing therapy for treatment of seizures in critically ill patients, and monitoring for cerebral ischemia, are presented. Areas requiring further development of CEEG monitoring techniques and indications are discussed.

Aged↗
PubMed2003

European Concerted Action on Anticoagulation (ECAA): an assessment of a method for ISI calibration of two whole blood point-of-care PT monitor systems based on lyophilized plasmas using whole blood equivalent PT.

Previously, the attempt to simplify the International Sensitivity Index (ISI) calibration of the CoaguChek Mini whole blood point-of-care test prothrombin time (PT) monitor system was successful using lyophilized plasmas from coumarin-treated patients but not with lyophilized artificially depleted plasmas. With the TAS PT-NC monitor system, both types of plasma failed to provide reliable calibrations. The present study assesses a procedure for the ISI calibration of a TAS PT-NC and CoaguChek Mini whole blood point-of-care test PT monitor systems using lyophilized plasmas. Using lyophilized artificially depleted and coumarin plasma calibrations, we have evaluated a correction for the monitor displayed PT. This was based on a 'line of equivalence' derived from the relationship between whole blood and fresh plasma PT with both types of monitor system. With the TAS PT-NC, the use of this 'line of equivalence' resulted in reliable ISI with both lyophilized coumarin and artificially depleted plasmas. There was no significant difference between mean monitor and mean reference International Normalized Ratio (INR) with the artificially depleted plasmas. With the lyophilized coumarin plasma calibrations there was only a small INR difference. Correction with the 'line of equivalence' therefore facilitates calibration of the TAS PT-NC with lyophilized plasmas. With the CoaguChek Mini, the correction based on the 'line of equivalence' did not improve results but was not required with this system.

Blood Preservation↗
PubMed1998

Continuous ambulatory haemodynamic monitoring with an implantable system. The feasibility of a new technique.

AIMS: This study evaluates the feasibility and safety of a completely implantable system for long-term ambulatory monitoring of important haemodynamic parameters in patients with severe cardiopulmonary disease. METHODS: The design of the implantable monitoring system is similar to a conventional single lead pacemaker. A lead with incorporated biosensors for the continuous recording of pressure and oxygen saturation signals is positioned in the right ventricle and connected to a monitor and memory device subcutaneously implanted like an ordinary pacemaker can. RESULTS: Five patients with implanted haemodynamic monitoring systems have been followed for from 7 to 16 months. Continuous measurements of activity, heart rate, mixed venous oxygen saturation and estimated pulmonary artery diastolic pressure were registered with variable resolution during daily living and predefined provocations. The memory covered a maximum of 3 weeks at low resolution. The monitored parameters showed an adequate and significant response to various haemodynamic situations. Except for the demand of recalibration of two oxygen sensors, there were no technical problems and the quality of data were excellent. CONCLUSION: Long-term ambulatory haemodynamic monitoring is feasible and potentially useful for the management of patients with severe cardiopulmonary disease.

Activities of Daily Living↗
PubMed1999

Pharyngeal pH monitoring in patients with posterior laryngitis.

OBJECTIVE: To evaluate the diagnostic value of 3-site 24-hour ambulatory pH monitoring in patients with posterior laryngitis (PL) and the prevalence of esophageal abnormalities in this patient group. METHODS: Twenty patients with PL and 17 healthy volunteers were studied as controls. Control subjects had transnasal esophagogastroduodenoscopy (T-EGD) and ambulatory pH monitoring. Patients underwent T-EGD, ambulatory pH monitoring, and barium esophagram. RESULTS: T-EGD documented no abnormality in controls. Esophagitis was present in 2 PL patients, and hiatal hernia in 3. Ambulatory pH monitoring showed that 15 PL patients and 2 controls exhibited pharyngeal acid reflux. Barium esophagram documented gastroesophageal reflux in 5 PL patients. However, none of these barium reflux events reached the pharynx. All PL patients with barium esophagram evidence of gastroesophageal reflux also showed pharyngeal acid reflux by pH monitoring. CONCLUSION: Pharyngeal acid reflux is more prevalent in patients with PL than in healthy controls. Patients with PL infrequently have esophageal sequelae of reflux disease. Ambulatory 24-hour simultaneous 3-site pharyngoesophageal pH monitoring detects gastroesophagopharyngeal acid reflux events in most patients with PL.

Adolescent↗
PubMed1997

The KID study IV: effects of inpatient rehabilitation on the frequency of glucose self-monitoring, quality of further primary care, on time being unable to work and on everyday psychic strain of type I and type II diabetics--a one-year follow-up. Kissingen Diabetes Intervention Study.

The Kissingen Diabetes Intervention Study (KID) evaluated 1,050 diabetic patients of the German Federal Insurance Institution for Salaried Employees (BfA) admitted for inpatient rehabilitation in a single-center, prospective, longitudinal study which was carried out to collect data concerning the structure of the patient cohort, socioeconomic factors, psychological data and state of medical care by consecutively registered random tests. These results have already been published. We will now report on the outcome 6 and 12 months after inpatient treatment. Consisting of rather young diabetics in higher professional standing, our patient cohort is especially interesting for health policy. The numbers of type I diabetics and of insulin-treated type II diabetics who self-monitor blood glucose levels several times daily significantly increased after inpatient rehabilitation. This situation is maintained 6 and 12 months after discharge. The number of type II diabetics on diet or oral hypoglycemics who do not monitor urinary glucose levels at all, is significantly reduced. The frequency of daily or weekly checks is significantly raised even after 12 months. Due to inpatient diabetic education, self-monitoring of glucose levels plays a more important role in primary care of these patients. 68.5% of all type I and about 60% of all type II diabetics receive test material without problems and are encouraged to continue monitoring. However, about 30% of type I and type II diabetics under primary-care management are still supplied with test material only when especially demanding it. The frequency of consultations in primary care diabetic management remains unchanged after inpatient treatment. The quality of diabetic management in primary care is improved by patient education. Monitoring of HbA1 is significantly increased in type I diabetics and significantly increased in type II diabetics. A similar development is seen in monitoring urinary albumin excretion but here are still deficits. For type II diabetics, the body weight and serum lipids are increasingly controlled main parameters. But in many places and especially in the case of type II diabetics the fasting glucose level is still used as main parameter. Compared with the 6 months prior to inpatient treatment, times when type I and type II diabetics are unable to work are significantly reduced in the 6 months and 12 months after-wards. Evaluating individual profiles of psychosocial strain shows that the more intense confrontation with problems of the disease and demands of the treatment can lead to a poorer quality of life in several categories. This was seen in the categories anxiety, depression, fear of hypoglycemias in the case of type I diabetics, restriction of leisure time activities, relationship with the partner and acceptance of disease. Only in the categories patient-physician relationship and professional strain was an improvement found. These alterations are still demonstrable after 6 and 12 months.

Absenteeism↗
PubMed2000

Multiparameter brain tissue monitoring--correlation between parameters and identification of CPP thresholds.

Continuous monitoring of brain interstitial gas concentrations allows direct regional evaluation of the pathophysiology of cerebral tissues. We have incorporated the Paratrend 7 (P7) multiparameter sensor into our established multimodal monitoring of head injured patients, to investigate the relationship between brain and arterial pO2, pCO2, and pH, as well as defining thresholds for cerebral perfusion pressure (CPP). A P7 sensor was inserted into the brain tissue of 40 adult head injured patients via a modified Camino bolt or triple lumen bolt. A second sensor was placed in the femoral artery for continuous monitoring of blood gases. Data signals from 19 monitored parameters were collected onto computer at the bedside for up to 14 days. No complications were seen. For individual patients the changes in brain tissue parameters showed large variations over 24 hours and the relationship between parameters varied considerably both between patients and during the period of monitoring any one individual. Changes related to periods of arterial desaturation, cerebral hypoperfusion and therapeutic manoeuvres could be seen. Good correlation was seen between brain pCO2 and arterial pCO2 (r = 0.58). Poor correlation was seen between CPP and brain pO2, and between brain pO2 and ICP. However, by grouping values for intracranial pressure (ICP) and CPP, thresholds for brain tissue pO2 were identified in 16 patients where CPP fell below 60 mmHg. No patients where CPP was always > 60 mmHg showed a significant threshold for a drop in brain pO2 (n = 16). In conclusion, the P7 shows potential as a monitor of regional brain oxygenation and for detection of potentially damaging secondary insults. The results must be interpreted whilst considering catheter position, autoregulation and systemic arterial changes for each individual.

Adolescent↗
PubMed2001

Recent advances in continuous glucose monitoring.

Continuous glucose monitoring, providing more detailed information on glucose excursions than single spot measurements, should help to improve the therapy in diabetic patients and is also required for feedback-controlled insulin delivery. At the Institute for Diabetes-Technology in Ulm, founded by EF Pfeiffer, a portable glucose sensor for continuous tissue glucose monitoring has been developed. The combination of microdialysis and enzymatic amperometric glucose measurement implemented in this device marked a break-through in achieving reliable and precise continuous tissue glucose monitoring. In several studies, we have demonstrated that continuous subcutaneous glucose monitoring for up to 72 hours is feasible under 'in-house' and 'daily life' conditions in diabetic patients. The measured tissue glucose concentrations correlated closely to glucose control measurements in venous and capillary blood. A reliable continuous glucose monitoring device is a prerequisite for the development of an artificial pancreas. Our group developed an algorithm for subcutaneous application of the fast acting insulin analogon lispro. In experiments performed over 7 and 24 hours good metabolic control was achieved by algorithm-based insulin application. In addition, the algorithm was able to maintain acceptable metabolic control during and after moderate physical exercise. Further work is needed to optimize continuous tissue glucose monitoring systems and to develop a closed loop system for insulin application based on continuously measured tissue glucose concentrations.

Algorithms↗
PubMed2002

[Results of laryngeal nerve monitoring during thyroid operations--Studies and value for clinical practice].

Injuries of the laryngeal nerve still remain a source of morbidity for patients undergoing surgery for the thyroid gland. The incidence of permanent damage of the nerve varies from 0.5 % to 2.7 % depending on the series, but for special thyroid diseases like thyroid carcinoma or goiter recurrence the damage of the recurrent laryngeal nerve could be up to 25 %. For that reason several methods of monitoring the movement of the nerve while stimulation have been proposed. Such as inserting a needle into the vocal muscles or working with a surface laryngeal electrode that is attached above the cuff of the tube. For neither of those methods of nerve monitoring severe complications were described. The purchase costs for all the equipment are between 25.000 to 30.000 DM. All the published data regarding monitoring of the laryngeal nerve have been only observation studies with no control group and for that reason the results of the studies could not be obligatory statements. Furthermore not every nerve palsy has been identified by the monitoring of the laryngeal nerve, this method has a sensitivity of less than 70 %. Monitoring of the laryngeal nerve is a helpful clinical tool not only for training of surgeons but also during complicated thyroid surgery. Monitoring is especially useful for operations of thyroid carcinoma or revision procedures. But at the moment there is no randomised study available that shows any superiority of this new and expensive method over the standard therapy, therefore further studies are necessary. Until these studies exist the anatomical localisation of the nerve during surgical dissection is still the gold standard.

Humans↗
PubMed2005

Portable monitoring in the diagnosis of the obstructive sleep apnea syndrome.

Portable monitors are classified into three levels (Level II, III, and IV) with decreasing measurements of sleep and respiratory variables. A full overnight sleep study with respiratory measurements and sleep staging (polysomnography) unattended by a sleep technician is Level II, three or more respiratory channels and heart rate generally without sleep staging either attended or unattended is Level III, and one or two channels attended or unattended, usually including oximetry, is Level IV. To date, some Level III portable monitors appear to have sufficient specificity to diagnose the obstructive sleep apnea (OSA) syndrome but are not sufficiently sensitive to exclude OSA. Attended portable monitoring appears to provide better sensitivity and specificity than unattended portable monitoring and is an option for diagnosis of OSA. The role of portable monitoring is evolving but at this time cannot substitute for attended polysomnography as a standalone approach. The exact place of portable monitoring and the cost-benefit depends on local circumstances and cannot be generalized at this time.

Cost-Benefit Analysis↗