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Patrick Chow-In Ko

Publications and source records attributed to Patrick Chow-In Ko.

At least 19 recordsLinked to original sources
PubMed2006

The demand for prehospital advanced life support and the appropriateness of dispatch in Taipei.

INTRODUCTION: Implementing prehospital advanced life support (ALS) services requires more medical and societal resources in training and equipment. The actual demand for ALS services in our communities was not clear. To ensure good use of expensive resources, it is important to evaluate the demand and appropriateness of ALS services before full-scale implementation takes place. OBJECTIVE: To evaluate the rate and characteristics of demand for ALS, and the appropriateness of ALS dispatch of the emergency medical service (EMS) system in metropolitan Taipei City. METHODS: A retrospective, cross-sectional analysis of the EMS records of Taipei City Fire Department from April 1999 to December 2000 was conducted. Stratified random sampling of all EMS records in the second week of January, April, July and October of 2000 were obtained, along with the corresponding ALS dispatch records. Retrospective ALS demand criteria, including the chief complaints, mechanisms of injury/illness, initial vital signs and types of care rendered, were developed to estimate the rate of ALS demand. ALS demand is expressed as the percentage of cases fulfilling ALS criteria over the total number of EMS cases. Appropriate ALS dispatches were those ALS dispatches determined as fulfilling the ALS demand criteria. RESULTS: Among the sampled 5433 EMS cases, 490 (9.02%) were determined as a demand for ALS care. ALS demands varied from region to region, and were higher during winter months and afternoon rush hours. There were 175 actual ALS dispatches, accounting for 3.22% of the sampled EMS services. The triage performance was suboptimal: the appropriateness of ALS dispatch was 37.14%; the overtriage rate was 72.86%. CONCLUSION: Around nine percent of EMS calls demand ALS services. The current triage performance for proper ALS dispatch was suboptimal. A correct ALS dispatch protocol and more dispatcher training programmes should be established in the communities to ensure best use of valuable ALS resources.

Advanced Cardiac Life Support↗
PubMed2006

Cost-effectiveness of different advanced life support providers for victims of out-of-hospital cardiac arrests.

BACKGROUND/PURPOSE: The survival rate of out-of-hospital cardiac arrest (OHCA) is only about 1.4% in Taiwan. The best configuration to achieve optimal outcomes in OHCA is still uncertain for many communities. The purpose of this study was to investigate the cost-effectiveness of two models of providing advanced life support (ALS) services, emergency medical technicians (EMTs) vs. emergency physicians (EPs), in a two-tiered emergency medical services (EMS) system. METHODS: This was a prospective, observational, multicenter study comparing ALS provided by EMTs vs. EPs for the management of victims of OHCA. The study population consisted of patients experiencing OHCA of non-traumatic origin in Taipei city, Taiwan, between November 1999 and December 2000, for whom ALS was activated. We performed a cost-effectiveness analysis to determine the economic attractiveness of these two ALS provider programs. The outcome measurements were aggregate costs, survival and incremental cost per life saved. Sensitivity analyses were performed on all variables. RESULTS: The expected total cost per OHCA patient was 2,248.19 US$ and 832.07 US$ for the EMT and EP programs, respectively. The overall survival rate was 4.4%. The survival rate was 9.3% for the EMT program and 2.6% for the EP program. The incremental cost-effectiveness ratio (ICER) of EMTs vs. EPs was 21,136 US$ per life saved. The ICER was sensitive to hospital admission cost changes and the probability of survival to discharge in patients admitted to hospital in the EMT program. The increased survival rate of OHCA patients in the EMT program may be attributable to the services of the hospital and/or the EMT program. CONCLUSION: The use of EMTs as ALS care providers for OHCA patients in the two-tiered EMS system resulted in a reasonable cost-effectiveness ratio. EMTs could be considered as the second tier of EMS systems in urban areas in Taiwan.

Advanced Cardiac Life Support↗
PubMed2005

Infections in the survivors of out-of-hospital cardiac arrest in the first 7 days.

OBJECTIVE: To evaluate the incidence, risk factors, foci, isolated organisms, and outcomes of infections in the survivors of out-of-hospital cardiac arrest (OHCA) within the first 7 days after resuscitation. DESIGN AND SETTING: Retrospective cohort study in the intensive care unit of a university hospital. PATIENTS AND PARTICIPANTS: We enrolled 117 survivors of adult nontraumatic OHCA victims who survived more than 24 h between January 1999 and May 2004. We collected patients' demographics, the causes and initial electrocardiographic rhythm of cardiac arrest, and the process of cardiopulmonary resuscitation. The incidence, clinical presentations and outcomes of infections occurring in the first 7 days after resuscitation were evaluated. Variables were compared between the infected and noninfected patients. MEASUREMENTS AND RESULTS: Among our OHCA survivors asystole was the most common initial rhythm (66%). Eighty-three patients (71%) were found to have infection. Pneumonia was the most common infection (61%) followed by bacteremia (13%). Although the Gram-negative bacteria were responsible for most infections, the most commonly isolated organism was Staphylococcus aureus. The infection group had more patients with dementia and noncardiac causes of OHCA. The survival curves did not differ significantly between infection and non-infection groups. CONCLUSIONS: Infections were common in OHCA survivors during the first 7 days. The most common responsible organisms were Gram-negative bacteria, and the most commonly isolated organism was S. aureus. Infections in the early stage after return of spontaneous circulation did not change the hospital mortality and hospitalization duration.

Aged↗
PubMed2005

Evaluating the quality of prehospital cardiopulmonary resuscitation by reviewing automated external defibrillator records and survival for out-of-hospital witnessed arrests.

OBJECTIVES: Without an easy method to monitor the performance of prehospital cardiopulmonary resuscitation (CPR), earlier studies have not been able to assess the quality of CPR. In this study, we have used a new approach to evaluate prehospital CPR performance and the impact on outcome using data retrieved from the automatic external defibrillators (AED). MATERIALS AND METHODS: Electrocardiography (ECG) and voice records from AED data cards from 633 out-of-hospital cardiac arrests (OHCA) were reviewed. Fifty-two witnessed cardiac arrests in ventricular fibrillation (VF) requiring post-shock CPR underwent an independent, structured review by two physicians. The adequacy of prehospital CPR was defined on the basis of noticeable deflection of the ECG with chest compressions, the actual number of chest compressions delivered per minute, and the continuity of prehospital CPR at the scene and during transport. Outcome measures included return of spontaneous circulation (ROSC) and survival to hospital admission and discharge. RESULTS: The quality of prehospital CPR was judged as adequate in 15 (29%, 95%; CI: 18-42%) and inadequate in 37 (71%, 95%; CI: 58-82%) of the consensus. Adequate CPR performance resulted in a higher rate of ROSC at the scene (53% versus 8%, 95% CI of the difference 14-76%), and survival to hospital discharge (53% versus 8%, 95% CI of the difference 14-76%). Two reviewers agreed on whether CPR was adequate in 92.3% of cases, with a kappa of 0.82. CONCLUSIONS: The quality of prehospital CPR is associated with a greater likelihood of survival in witnessed VF arrests in need of post-shock CPR. The potential of widely available electrocardiography and voice records in AEDs in providing a convenient and real-time evaluation of prehospital CPR should be explored further.

Adolescent↗
PubMed2005

Better adherence to the guidelines during cardiopulmonary resuscitation through the provision of audio-prompts.

OBJECTIVE: Quality assurance to optimize clinical resuscitation performance is important. The aims of the present study were to identify the deficiencies in the clinical practice of resuscitation by motion analysis of video-recorded cardiopulmonary resuscitation (CPR), and to evaluate the effectiveness of quality improvement strategies based on audio-prompt methods. MATERIALS AND METHODS: A two-stage prospective trial was conducted. The first stage (observation group) was designed to identify any major clinical nonconformity to current resuscitation guidelines by videotaped CPR sessions. The second stage (intervention group) was designed to evaluate the effectiveness of audio prompts in ameliorating the problems identified at the first stage. The demographic data of patients and CPR variables between the two groups were analysed. RESULTS: A total of 30 resuscitation attempts were recorded during study period: 17 patients were in the observation group and 13 patients in the intervention group. Inadequate number of chest compressions per minute, lack of re-oxygenation during prolonged intubation attempts and unnecessary hands-off periods were identified as the three most important deficiencies in CPR practice. Compared to the observation group, the intervention group showed a significant improvement in the hands-off period per minute during CPR (12.7 +/- 5.3 s versus 16.9+/-7.9 s, P < 0.05), the total hands-off time during CPR (164 +/- 94 s versus 273 +/- 153 s, P < 0.05), the proportion of intubation attempts taking under 20 s (56.3% versus 10%, P < 0.05). CONCLUSIONS: Audio-prompts can improve the adherence to current CPR guidelines in the clinical setting significantly. The quality improvement measures described in this study are helpful in translating CPR knowledge into clinical practice.

Adult↗
PubMed2005

Machine and operator performance analysis of automated external defibrillator utilization.

BACKGROUND AND PURPOSE: The availability of an automated external defibrillator (AED) can improve the outcome of patients with out-of-hospital cardiac arrest (OHCA). On June 1, 2000, Taipei City became the first city in Taiwan to equip emergency medical services personnel with AEDs. This study was conducted to assess the performance of the AED machine in detecting ventricular fibrillation (VF) and ventricular tachycardia (VT) in the population, and to assess operator performance in its use. METHODS: AED use in OHCA patients was assessed over a 1-year period. Electrocardiography and voice records retrieved from AED data cards were analyzed. A shockable rhythm was defined as either VF or VT. AED machine performance was assessed based on the correct identification of these rhythms. Operator performance was evaluated according to American Heart Association guidelines. RESULTS: A total of 978 AED rhythm analyses were obtained for 653 OHCA patients. The sensitivity and specificity for detecting shockable rhythms by the AED machine were 90.0% (95% confidence interval [CI], 85.3% to 93.3%) and 100% (95% CI, 99.5% to 100%), respectively. Sensitivity for coarse VF, fine VF, rapid VT, and slow VT was 97.5%, 74.2%, 63.6% and 60.0%, respectively. An AED was deployed in 18 non-OHCA patients and in 119 patients after they had been moved into the ambulance. Non-compliance with standard procedures occurred during AED use in 162 patients, including interference of movement by cardiopulmonary resuscitation (CPR) in progress in 69, untimely machine turn-off in 49, leads fell off or disconnected in 33, failure of shock delivery after charge in 28, and interference of movement other than CPR in 22. CONCLUSIONS: This study found that the AED machine has high specificity and high sensitivity in detecting VF and VT, especially coarse VF. Efforts are needed to improve the timing of AED deployment and emergency medical technician compliance with standard procedures.

Adolescent↗
PubMed2005

Near-fatal methemoglobinemia after recreational inhalation of amyl nitrite aerosolized with a compressed gas blower.

Adverse effects associated with recreational inhalation of nitrites are usually mild and rarely life-threatening. We report a rare case of near-fatal methemoglobinemia after inhalation of amyl nitrite after aerosolizing the liquid using a compressed gas blower designed to clean photographic equipment that employed hydrofluoroalkane-134a as a propellant. A 31-year-old previously healthy male became dyspneic and fainted soon after the recreational inhalation of amyl nitrite aerosolized using a compressed gas blower. He was brought to the emergency department with severe cyanotic appearance and profound shock. Oxygen saturation was 82%, unresponsive to oxygen supply. His methemoglobin blood level was 52.2%. After 100 mg of methylene blue (2 mg/kg body weight) was administered intravenously, he recovered consciousness, and dyspnea and cyanosis subsided gradually. This case illustrates the extraordinary hazard of the use of a compressed gas blower in the recreational inhalation of nitrites. Prompt recognition and rapid antidotal treatment may adequately correct near-fatal overdose associated with recreational use of amyl nitrite.

Adult↗
PubMed2004

Tracheal rupture complicating emergent endotracheal intubation.

Tracheal rupture is rare in clinical practice. We present 2 female patients with tracheal rupture after emergent endotracheal intubation from different injury mechanisms; penetrating injury of using stylet during intubation in one case and overinflation of cuff of the endotracheal tube under rapid sequence intubation in another. The lesions of rupture could be detected by bronchoscopy and reconstructive 3-dimensional computed tomography. Both cases received surgical repair without complication. In our report, reconstructive 3-dimensional computed tomography scrupulously detected the rupture sites and provided the noninvasive modality for diagnosis. We review the literature of tracheal rupture after emergent endotracheal intubation in respects of the diagnosis, the possible mechanisms of the injury, and suggest strategies of management.

Aged↗
PubMed2004

Sequential symptomatic analysis in probable severe acute respiratory syndrome cases.

STUDY OBJECTIVE: Previous reports on severe acute respiratory syndrome (SARS) described mainly its symptoms. However, the time sequence of symptom development was rarely discussed. The objective of this study is to chronologically document the time sequence of symptom development in probable SARS cases and compare that of the febrile non-SARS cases, thus providing valuable information for early recognition of the disease. METHODS: This prospective, descriptive, cohort study was conducted in an academic university hospital in Taipei, Taiwan, from March 14 through May 12, 2003. Patients presenting to the emergency department (ED) with a temperature of at least 38.0 degrees C (> or =100.3 degrees F) and exposure history were evaluated with a structured protocol. Detailed time sequences of individual symptoms were recorded, and chest radiography and laboratory test results were obtained. Probable SARS cases were determined by the Center of Disease Control Taiwan. Children younger than 15 years and suspected SARS patients with negative polymerase chain reaction results were excluded from final analysis. RESULTS: Seventy-nine SARS and 220 non-SARS cases were analyzed. The major clinical symptoms of SARS patients on ED presentation were myalgia, loose stool or diarrhea, nonproductive cough or dyspnea, headache, and chills. Upper airway symptoms, including rhinorrhea and sore throat, were rarely seen in the SARS patients but were common in the non-SARS group. Characteristic symptom sequence, consisting of initial fever accompanied by diarrhea and myalgia and then progressive respiratory symptoms, was identified in 55 SARS patients (69.6%; 95% confidence interval [CI] 0.60 to 0.80) but only 7 (3.2%; 95% CI 0.008 to 0.05) non-SARS patients. Chest radiographic abnormality may precede lower respiratory tract symptoms in some SARS patients. CONCLUSION: During an outbreak period, recognition of possible SARS cases depends on the heightened awareness of its clinical presentation. Aside from travel and contact history, the time sequence of the accompanying symptoms of SARS should help first-line physicians screen SARS patients at an early stage.

Adult↗
PubMed2004

Validation of a novel severe acute respiratory syndrome scoring system.

STUDY OBJECTIVE: In a pilot study conducted during March 14 to April 2, 2003, 2 severe acute respiratory syndrome (SARS) screening scores were developed for predicting SARS among febrile patients presenting to the emergency department (ED). The objective of this study is to validate these scoring systems with a different set of patients. METHODS: All adult patients with documented fever, measured at home or at the hospital, and presenting to the ED of National Taiwan University Hospital, a 2,400-bed tertiary care teaching hospital in northern Taiwan, were prospectively enrolled. Two previously developed SARS screening scores were applied to all patients. The final diagnosis of SARS was made by the Expert Committee of the Center for Disease Control Taiwan, Republic of China, according to the criteria of Centers for Disease Control and Prevention, Atlanta, GA. RESULTS: A total of 239 adult patients, including 117 men and 122 women, were enrolled. Eighty-two patients were finally diagnosed with SARS. Compared with the SARS patients in the derivation cohort, those in the validation cohort were older (44.5+/-15.9 versus 33.9+/-15.9 years), more likely to acquire the disease locally (76.8% versus 37.5%), and more likely to have cough before or during fever. For the non-SARS patients, cases in the validation cohort presented with less cough and coryza but more diarrhea. For the 4-item symptom score, the sensitivity reached 96.3% (95% confidence interval [CI] 89.7% to 98.7%) and the specificity 51.6% (95% CI 43.8% to 59.3%). For the 6-item clinical score, the sensitivity reached 92.6% (95% CI 84.8% to 96.6%) and the specificity 71.2% (95% CI 63.6% to 77.7%). When the clinical score was applied to patients with a positive symptom score, the combined sensitivity reached 90.2% (95% CI 82.0% to 95.0%), and the combined specificity reached 80.1% (95% CI 73.2% to 85.6%). CONCLUSION: This prospective study validated the scoring system previously developed by using a different cohort. The scoring systems could be applied to settings where mass screening of SARS is needed during future outbreaks.

Adolescent↗
PubMed2004

Impact of community-wide deployment of biphasic waveform automated external defibrillators on out-of-hospital cardiac arrest in Taipei.

OBJECTIVES: To determine the impact and outcome of out-of-hospital cardiac arrests (OHCA) while using automated external defibrillators (AED) with biphasic waveforms and its effectiveness when using the Utstein Style community-wide in Taipei. MATERIAL AND METHODS: A one-year study was conducted to collect OHCA patients with AED utilization prospectively in Taipei City. All events and variables were recorded in the Utstein Style. Electrocardiography and voice records recovered from AED data cards were analysed. The endpoints were survival outcomes. RESULTS: Of 653 OHCA patients with AED utilization, only 80 (12.6%) patients with 635 true arrests presented with ventricular fibrillation or tachycardia (VF/VT) as the initial rhythm. The interval between call-to-shock was 5 min longer than call-to-EMS arrival (9.3 min versus 4.0 min). Fourteen (25%) of the 55 witnessed VF/VT arrests survived to home discharge. Ninety-seven percent of shockable rhythms were successfully terminated with less than three shocks. For all OHCA patients, initial rhythm of VF/VT (OR 3.4; 95% CI = 1.2-9.4), witnessed status (OR 4.7; 95% CI = 1.3-16.6), and presence of organised rhythm irrespective of pulse during prehospital resuscitation (OR 9.2; 95% CI = 3.2-26.8) demonstrated an independent association with survival to home discharge. For VF/VT arrests, witnessed status, shorter call-to-shock time, high successful rate of the first shock, fewer averaged number of shocks delivered for each patient, and presence of an organised rhythm during prehospital resuscitation showed a likelihood to predict to predict discharged survival in univariate analysis. CONCLUSIONS: Low frequency of VF arrests is unique to certain eastern populations but without a reduction of AED shock efficacy with biphasic waveform. Besides initial VF and witnessed status, a prehospital post-shock organized rhythm irrespective of pulse appears to be correlated to survival. Certain circumstances in a congested metropolitan city consume time to deliver shocks even after EMS arrival, and might require bystander or public access defibrillation.

Aged↗
PubMed2004

Predictive model of diagnosing probable cases of severe acute respiratory syndrome in febrile patients with exposure risk.

STUDY OBJECTIVE: Since the World Health Organization issued a global alert about severe acute respiratory syndrome (SARS) on March 12, 2003, the illness has become a major public health challenge worldwide. The objective of this study is to identify the clinical risk factors of SARS and to develop a scoring system for early diagnosis. METHODS: The detailed clinical data of all patients presenting to the emergency department (ED) with a temperature higher than 38.0 degrees C (100.3 degrees F), documented at home or at the ED, and risks of exposure to SARS within 14 days were assessed. The diagnosis of probable SARS was made according to the definition of the Centers for Disease Control and Prevention. Items with significant differences among symptoms, signs, and laboratory tests on presentation between SARS and non-SARS groups were determined and used to develop the scoring system. RESULTS: Seventy patients were enrolled and 8 were diagnosed as probably having SARS. None of the initially discharged patients or their relatives developed SARS. Compared with the non-SARS group, the SARS group was younger (33.9+/-15.9 years versus 44+/-9.8 years; P=.02), had a higher percentage of fever prolonged more than 5 days (87.5% versus 6.5%; P<.01), myalgia (75% versus 27.4%; P=.01), and diarrhea (50% versus 9.7%; P=.02); had less occurrence of cough before or during fever (0% versus 64.5%; P=.01); and had lower absolute lymphocyte (0.9+/-0.3x10(9)/L versus 1.5+/-1.1x10(9)/L; P<.01) and platelet counts (144.1+/-36.3x10(9)/L versus 211.6+/-78.8x10(9)/L; P=.02). A 4-item symptom score based on the presence of cough before or concomitant with fever, myalgia, diarrhea, and rhinorrhea or sore throat detects SARS with 100% sensitivity and 75.9% specificity; a 6-item clinical score based on lymphopenia (<1.0x10(9)/L), thrombocytopenia (<150x10(9)/L) and the 4 symptom items detects SARS with 100% sensitivity and 86.3% specificity. CONCLUSION: Certain symptoms and laboratory tests indicate higher risk of febrile probable SARS. In nonendemic areas, the febrile patients with recent contact with SARS or travel history to endemic areas could be screened for the probability of SARS by the use of clinical and symptom scores.

Adolescent↗
PubMed2004

A wireless PDA-based physiological monitoring system for patient transport.

This paper proposes a mobile patient monitoring system, which integrates current personal digital assistant (PDA) technology and wireless local area network (WLAN) technology. At the patient's location, a wireless PDA-based monitor is used to acquire continuously the patient's vital signs, including heart rate, three-lead electrocardiography, and SpO2. Through the WLAN, the patient's biosignals can be transmitted in real-time to a remote central management unit, and authorized medical staffs can access the data and the case history of the patient, either by the central management unit or the wireless devices. A prototype of this system has been developed and implemented. The system has been evaluated by technical verification, clinical test, and user survey. The evaluation of performance yields a high degree of satisfaction (mean = 4.64, standard deviation--SD = 0.53 in a five-point Likert scale) of users who used the PDA-based system for intrahospital transport. The results also show that the wireless PDA model is superior to the currently used monitors both in mobility and in usability, and is, therefore, better suited to patient transport.

Adult↗