ABSTRACT
The second wave of SARS?CoV?2 infection came as a hypoxic emergency and situation became worse in rural India, where undiagnosed COVID-19 patients died without any diagnosis or intervention. The primary aim of this innovative model was the early diagnosis of suspected SARS?CoV?2 cases, providing empirical treatment and timely referral to appropriate COVID care facilities. Fever was measured with infrared thermometer and oxygen saturation level with pulse oximeter. A total of 8203 people were screened, of which 274 persons were febrile and 69 (25%) were hypoxic too. Sixty?four out of 69 (93%) patients turned COVID?19 positive on reverse transcription?polymerase chain reaction. At the end of 3 weeks, 48/64 (75%) patients were successfully discharged. This model can be easily implemented in resource?limited regions to identify and prioritize the patients not only in this pandemic but also in outbreak of other communicable diseases.
ABSTRACT
Objective:To investigate the knowledge, attitudes, and practices (KAP) of pulse oximetry among pediatric healthcare providers in China and analyze the factor influencing the KAP.Methods:A self-developed questionnaire was used for an online research on the KAP of 11 849 pediatric healthcare providers from 31 provinces, autonomous regions, and municipalities of China from March 11 to 14, 2022.The factors influencing the KAP of pulse oximetry among pediatric healthcare providers were examined by Logistic regression. Results:The scores of KAP, of pulse oximetry were 5.57±0.96, 11.24±1.25 and 11.19±4.54, respectively.The corresponding scoring rates were 69.61%, 74.95%, and 55.99%, respectively. Logistic regression results showed that the gender and working years of pediatric healthcare providers, the region they were located, and whether their medical institution was equipped with pulse oximeters were the main factors affecting the knowledge score (all P<0.05). Main factors influencing the attitude score of pediatric healthcare providers included their knowledge score, gender, educational background, working years, region, medical institution level, and whether the medical institution was equipped with pulse oximeters (all P<0.05). For the practice score, the main influencing factors were the knowledge score, gender, age, and whether the medi-cal institution was equipped with pulse oximeters (all P<0.05). Conclusions:Chinese pediatric healthcare providers need to further improve their knowledge about and attitudes towards pulse oximetry.Pulse oximeters are evidently under-used.It is urgent to formulate policies or guidelines, strengthen education and training, improve knowledge and attitudes, equip more institutions with pulse oximeters, and popularize their application in medical institutions.
ABSTRACT
Background:The World Health Organization (WHO) integrated management of childhood illness (IMCI) protocol recommends treatment of chest indrawing in 2-59 months old children with oral amoxicillin by trained health facility workers. Whereas, the WHO/UNICEF integrated community case management (iCCM) protocol recommends referral by community level health workers (CLHWs) to a health facility. This study aims to evaluate whether CLHWs can treat chest indrawing pneumonia effectively and safely.Methods:Thismulti-centre cluster randomized controlled open label, non-inferiority trial will be conductedin Bangladesh, Ethiopia, India and Malawi. All sites will use a common protocol with the same study design, participants, intervention, control and outcomes. CLHWs will identify 2-59 months old children with chest indrawing. Study supervisors, trained in the iCCM protocol, will confirm CLHWs’ findings. Pulse oximetry will be used to identify hypoxaemic children. In the intervention group, enrolled children will be treated with oral amoxicillin for 5 days, and in the control group they will be referred to ahealth facility, after providing first dose of oral amoxicillin. An independent outcome assessor will visit each enrolled child on days 6 and 14 of enrolment, to assess study outcomes.Conclusions:If CLHWs can effectively and safely treat chest indrawing pneumonia in 2-59 months old children, it will increase access to pneumonia treatment substantially, as in many settings, health facilities and trained health workers are not easily accessible. Moreover, this evidence will contribute towards the review of the current iCCM protocol and its harmonization with the IMCI protocol. Trial Registration:The trial is registered at AZNCTR International Trial Registry as ACTRN12617000857303
ABSTRACT
Background:WHO does not recommend community-level health workers (CLHWs) using integrated community case management (iCCM) to treat 7-59 days old infants with fast breathing with oral amoxicillin, whereas World Health Organization (WHO)integrated management of childhood illness (IMCI) recommends it. We want to collect evidence to help harmonization of both protocols.Methods:A cluster, randomized, open-label trial will be conducted in Africa and Asia (Ethiopia, Malawi, Bangladesh and India) using a common protocol with the same study design, inclusion criteria, intervention, comparison, and outcomes to contribute to the overall sample size. This trial will also identify hypoxaemia in young infants with fast breathing. CLHWs will assess infants for fast breathing, which will be confirmed by a study supervisor. Enrolled infants in the intervention clusters will be treated with oral amoxicillin, whereas in the control clusters they will be managed as per existing iCCM protocol. An independent outcome assessor will assess all enrolled infants on days 6 and 14 of enrolment for the study outcomes in both intervention and control clusters. Primary outcome will be clinical treatment failure by day 6. This trial will obtain approval from the WHO and site institutional ethics committees. Conclusions: If the research shows that CLHWs can effectively and safely treat fast breathing pneumonia in 7-59 days old young infants, it will increase access to pneumonia treatment substantially for infants living in communities with poor access to health facilities. Additionally, this evidence will contribute towards the review of the current iCCM protocol and its harmonization with IMCI protocol.Trial Registration:The trial is registered at AZNCTR International Trial Registry as ACTRN12617000857303.
ABSTRACT
Background: the efficiency of the diagnostic aids plays an important role in the treatment plan. This study aims to assess the diagnostic accuracy of dental pulse oximeter with a customized sensor holder, thermal test and electric pulp tester in assessing the actual pulp status and to evaluate the oxygen saturation level in control healthy teeth, non-vital and teeth with irreversible pulpitis. Material and methods: thirty-seven single canal teeth requiring endodontic therapy were included in the study. The selected teeth were tested with dental pulse oximeter, electric pulp test, cold spray, and heated gutta percha stick. Between each test a time lag of 2 minutes was allowed for the central sensitization to occur. Three blinded operators were involved in the study. The actual status of the pulp was evaluated after the initiation of endodontic treatment, by direct visual examination of the accessed cavity. The data was statistically analysed using (ANOVA) Analysis of Variance and Post-hoc Tukey test. Results: sensitivity of pulse oximeter, heat test, cold and electric pulp test, was 100, 25, 50, and 12, respectively. The specificity of these tests was 100, 72 81, and 77, respectively. The ANOVA showed that there was statistical difference between all the groups (p=0.0005). Post-Hoc Tukey revealed that there was statistical difference among all the groups, nonvital group (p=0.0005), control group (p=0.01) and for irreversible pulpitis (p=0.01). The overall diagnostic accuracy of pulse oximeter was 100% followed by cold test 66%, heat test to be 49% and electric pulp test to be 45%. Conclusion: the custom-made holder used in the present study aided in providing accurate response for pulp vitality testing. In this study the diagnostic accuracy was high with dental pulse oximeter followed by cold, heat and the least was electric pulp tester in different pulpal conditions. (AU)
Fundamentação: a eficiência dos meios de diagnóstico desempenha um papel importante no plano de tratamento. Este estudo tem como objetivo avaliar a precisão diagnóstica do oxímetro de pulso odontológico com um suporte de sensor personalizado, teste térmico e testador de polpa elétrico na avaliação da condição pulpar e na avaliação do nível de saturação de oxigênio em dentes controle saudáveis, não vitais e dentes com pulpite irreversível. Material e métodos: trinta e sete dentes de canal único que necessitavam de terapia endodôntica foram incluídos no estudo. Os dentes selecionados foram testados com oxímetro de pulso, teste pulpar elétrico, spray frio e bastão de guta-percha aquecido. Entre cada teste, foi permitido um intervalo de tempo de 2 minutos para a sensibilização central ocorrer. Três operadores cegos foram envolvidos no estudo. A condição real da polpa foi avaliada após o início do tratamento endodôntico, por meio de exame visual direto da cavidade de acesso. Os dados foram analisados estatisticamente pelo teste de Análise de Variância (ANOVA) e pelo teste Post-hoc de Tukey. Resultados: a sensibilidade do oxímetro de pulso, teste de calor, de frio e teste pulpar elétrico foi de 100, 25, 50 e 12, respectivamente. A especificidade desses testes foi de 100, 72 81 e 77, respectivamente. O teste de ANOVA mostrou que houve diferença estatística entre todos os grupos (p = 0,0005). O teste Post-Hoc de Tukey revelou que houve diferença estatística entre todos os grupos, grupo não-vital (p = 0,0005), grupo controle (p = 0,01) e pulpite irreversível (p = 0,01). A precisão diagnóstica geral do oxímetro de pulso foi de 100%, seguida pelo teste a frio de 66%, o teste de calor a 49% e o teste pulpar elétrico a 45%. Conclusão: o suporte personalizado utilizado no presente estudo ajudou a fornecer uma resposta precisa para o teste de vitalidade pulpar. Neste estudo, a precisão diagnóstica foi alta com o oxímetro de pulso dental, seguido do teste com frio e calor, sendo o teste elétrico o menos eficaz nas diferentes condições pulpares testadas.(AU)
Subject(s)
Humans , Adult , Middle Aged , Oximetry , Dental Pulp Cavity , EndodonticsABSTRACT
This study was conducted to compare the anesthetic effects of 2,2,2-tribromoethanol (TBE, Avertin®) in ICR mice obtained from three different sources. TBE (2.5%) was intraperitoneally injected at three doses: high-dose group (500 mg/kg), intermediate-dose group (250 mg/kg), and low-dose group (125 mg/kg). Anesthesia time, recovery time, end-tidal peak CO2 (ETCO₂), mean arterial blood pressure, heart rate, oxygen saturation (SpO₂), body temperature, pH, PCO₂, and PO₂ of the arterial blood were measured. Stable anesthesia was induced by all doses of TBE and the anesthesia time was maintained exhibited dose dependency. No significant differences in anesthetic duration were found among the three different strains. However, the anesthesia time was longer in female than in male mice, and the duration of anesthesia was significantly longer in female than in male mice in the high-dose group. The recovery time was significantly longer for female than male mice in the intermediate- and high-dose groups. In the ICR strains tested, there were no significant differences in the mean arterial blood pressure, SPO₂, arterial blood PCO₂, and PO₂, which decreased after TBE anesthesia, or in heart rate and ETCO₂, which increased after TBE anesthesia. In addition, body temperature, blood biochemical markers, and histopathological changes of the liver, kidney, and lung were not significantly changed by TBE anesthesia. These results suggested that ICR mice from different sources exhibited similar overall responses to a single exposure to TBE anesthesia. In conclusion, TBE is a useful drug that can induce similar anesthetic effects in three different strains of ICR mice.
Subject(s)
Animals , Female , Humans , Male , Mice , Anesthesia , Anesthetics , Arterial Pressure , Biomarkers , Body Temperature , Heart Rate , Hydrogen-Ion Concentration , Kidney , Liver , Lung , Mice, Inbred ICR , Oxygen , Sex CharacteristicsABSTRACT
To study the effect of microgravity on peripheral oxygen saturation (SpO ) in rats, tail-suspended rats were applied to simulate microgravity environment. SpO and arterial oxygen saturation (SaO ) were measured by pulse oximeter and arterial blood gas analyzer (ABGA) respectively on the 14th day, 21st day and 28th day in tail-suspended group and control group. Paired -test shows that SpO was significantly lower than SaO in tail-suspended group on the 14th day ( < 0.05), the 21st day ( < 0.05) and the 28th day ( < 0.01). The ANOVA results shows that modeling time had significant effect on SpO value but no effect on SaO value in tail-suspended group. These results indicate that pulse oximeter may be not suitable for oxygen saturation test in microgravity environment.
ABSTRACT
Resumen: ANTECEDENTES: la pulsioxímetria estima la saturación arterial de oxígeno mediante la absorción de un haz de luz infrarroja por la oxihemoglobina. OBJETIVO: determinar la validez y la confiabilidad interinstrumento de cinco pulsioxímetros comúnmente usados en la práctica clínica. MATERIAL Y MÉTODO: estudio transversal, analítico, realizado del 1 de enero de 2015 al 30 de octubre de 2016, en el que se incluyeron pacientes mayores de 18 años de edad, con línea arterial para toma de gasometría y se midió simultáneamente la saturación de oxígeno con cinco pulsioxímetros de uso habitual. Se determinaron medianas y porcentajes de los cinco pulsioxímetros entre sí mediante prueba de Friedman. RESULTADOS: se incluyeron 101 pacientes, 63 hombres y 38 mujeres. Se encontró similitud en las mediciones realizadas por cada pulsioxímetro con p = 0.08; todos los oxímetros se correlacionaron de manera positiva contra la prueba patrón de referencia (correlación de Pearson). Oxímetro 1: r = 0.90; oxímetro 2: r = 0.64; oxímetro 3: r = 0.57; oxímetro 4: r = 0.84 y oxímetro 5: r = 0.89; el área bajo la curva mostró oxímetro 1 (0.89), oxímetro 2 (0.88), oxímetro 3 (0.87), oxímetro 4 (0.83), oxímetro 5 (0.85) con p < 0.05. CONCLUSIONES: el pulsioxímetro número 1 muestra el mejor rendimiento comparado con la gasometría. Al comparar los oxímetros entre sí el rendimiento es igual.
Abstract: BACKGROUND: Pulse oximetry estimates the arterial oxygen saturation by absorption of an infrared light beam by oxyhemoglobin. OBJECTIVE: To determine the intraclass validity and reliability of five pulse oximeters commonly used in clinical practice. MATERIAL AND METHOD: A cross-sectional analytical study was done from January 1st 2015 to October 30 2016, including patients over 18 years old, with arterial line for blood gas sample and simultaneously oxygen saturation was measured with 5 pulse oximeters commonly used. Medians and percentages of the 5 pulse oximeters were determined by Friedman's test RESULTS: There were included 101 patients, 63 men and 38 women, with similarity in the measurements performed by each pulse oximeter with p = 0.08; all oximeters were positively correlated against the standard gold test (Pearson's correlation). Oximeter 1: r = 0.90; oximeter 2: r = 0.64; oximeter 3: r = 0.57; oximeter 4: r = 0.84 and oximeter 5: r = 0.89. The area under the curve showed oximeter 1 (0.89), oximeter 2 (0.88), oximeter 3 (0.87), oximeter 4 (0.83), oximeter 5 (0.85) with p < 0.05. CONCLUSIONS: The pulse oximeter number 1 shows a better performance when compared to the gasometry. When the oximeters are compared to each other the performance is the same.
ABSTRACT
Objective:To expound the importance of blood oxygen saturation index, and to analyze the detection method of oxygen saturation index. Besides, to provide scientific and reasonable basis for use and selection of clinical saturated pulse oximetry(SpO2) sensor. Methods: To adopt pertinence detection method to test six kinds of SpO2 sensors (included the original import, original domestic, import commission processing, domestic commission processing, integrated mode sensor and one-time sensor), and to detect and analyze their specifications.Results: The experiment results of six kinds of SpO2 sensor were analyzed, and their main characteristics were obtained. And then, different sensor was recommended to different department or situation according to the actual situation of different hospital.Conclusion: Various clinical department and requirement can give full play to the advantages of various types of sensor, fast detect blood oxygen index for patients, reasonably allocate SpO2 sensor, reduce using cost and improve diagnosis level, at the same time, effectively carry through adjuvant therapy after they select the most suitable SpO2 sensor.
ABSTRACT
El pulsioxímetro es una herramienta no invasiva esencial para el monitoreo de la saturación arterial de oxígeno. Utiliza la espectrofotometría para detectar sobre la piel dos intensidades de luz (600 y 900 nm) que proporcionan información de la perfusión tisular y cantidad de oxígeno transportada. Depende de un circuito de manipulación de corriente, dos diferentes fuentes emisoras de luz, un foto-detector y una unidad de procesamiento que permiten ajustar las intensidades de luz ante tejidos de diferentes características. En el presente trabajo, se propone un método de modulación por ancho de pulso alternativo para el control de la intensidad lumínica media, cuyo principio es la conmutación on/off de la corriente aplicada a los LEDs en la etapa de emisión. Este sistema permite modificar tanto el nivel de CD como la amplitud de la señal de CA de la onda fotopletismográfica e implica la reducción del número de componentes analógicos y consumo de energía. La metodología presentada permite regular la resolución de la señal muestreada y ofrece disminuciones del 21 % y 40 % en potencia comparado con los esquemáticos propuestos por Freescale Semiconductor, Inc. y Texas Instruments Incorporated respectivamente. El uso de señales sincronizadas moduladas en ancho de pulso con frecuencias por encima de 333 kHz y pasos de 50 ns para emitir luz, permitió una reducción 41% de potencia, respecto al sistema con modulación analógica del módulo MDK pulse oximeter.
Pulse oximetry is an essential optical based non-invasive tool for monitoring blood oxygen saturation. It uses spectrophotometry to detect two light intensities (600 and 900 nm) through the skin; it provides information on tissue perfusion and quantity of transported oxygen. The process relies on a current control circuit, two light emitting sources, a photodetector, and a digital signal processor that adjusts the light intensities for different tissue characteristics. This paper proposes an alternative method of pulse width modulation for controlling the mean light intensity level, whose principle is a pulse width nodulation of the current applied to the LEDs in the emitting stage. This system allows modifying the DC level and the amplitude of the AC signal of the photopletismographic wave. The results is the reduction of the number of analog components and power consumption. The methodology presented, it allows adjusting the definition of the sample signal and offers power reductions of 21% and 40% compared to schematics given by Freescale Semiconductor, Inc. and Texas Instruments Incorporated, respectively. Thus, by using synchronized signal pulse width modulation to emit light, with frequencies above 333 kHz and steps of 50 ns, it will allow power reductions of 41%, compared to the conventional analog modulation module MDK pulse oximeter.
O oxímetro de pulso é uma ferramenta não invasiva essencial para o monitoramento da saturação de oxigênio no sangue. Usa espectrofotometria para detectar a pele duas intensidades de luz (600 nm e 900) para fornecer informações de perfusão tecidual ea quantidade de oxigênio transportado. Depende de manuseamento corrente do circuito, duas fontes diferentes emissores de luz, um fotodetector e uma unidade de processamento para ajustar a intensidade da luz nos tecidos com características diferentes. Neste trabalho, um método de modulação de largura de pulso alternativa para controlar a intensidade de luz média, o princípio é o de ligar/desligar da corrente aplicada aos LEDs no palco questão é proposto. Este sistema permite modificar tanto o nível DC e a amplitude do sinal AC da forma de onda fotoplestimográfico e envolve a redução do número de componentes analógicos e consumo de energia. A metodologia apresentada permite ajustar a resolução do sinal de amostragem e oferece reduções de 21% e 40% da potência em comparação com o esquema proposto pela Freescale Semicondutor, Inc. e Texas Instruments Incorporated, respectivamente. Sinais sincronizados usando freqüências moduladas por largura de pulso acima de 333 kHz e 50 ns passos para emitir luz, permitiu uma redução de 41% de energia em comparação com módulo de oxímetro de pulso MDK sistema de modulação analógica.
ABSTRACT
Recent advance in technology has developed a lot of new aspects of clinical monitoring. We can monitor sedation levels during anesthesia using various electroencephalographic (EEG) indices, while it is still not useful for anesthesia depth monitoring. Some attempts are made to monitor the changes in sympathetic nerve activity as one of the indicators of stress, pain/analgesia, or anesthesia. To know the balance of sympathetic and parasympathetic activity, heart rate or blood pressure variability is investigated. For trend of cardiac output, low invasive monitors have been investigated. Improvement of ultrasound enables us to see cardiac structure and function continuously and clearer, increases success rate and decreases complication of central venous puncture and various kinds of nerve blocks. Without inserting an arterial catheter, trends of arterial oxygen tension or carbon dioxide tension can be monitored. Indirect visualization of the airway decreases difficult intubation and makes it easier to teach tracheal intubation. The changes in blood volume can be speculated non-invasively. Cerebral perfusion and metabolism are not ordinary monitored yet, but some studies show their usefulness in management of critically ill. This review introduces recent advances in various monitors used in anesthesia and critical care including some studies of the author, especially focused on EEG and cardiac output. However, the most important is that these new monitors are not almighty but should be used adequately in a limited situation where their meaning is confirmed.
Subject(s)
Humans , Anesthesia , Blood Pressure , Blood Volume , Carbon Dioxide , Cardiac Output , Cardiac Output, Low , Catheters , Critical Care , Critical Illness , Electroencephalography , Heart Rate , Intubation , Monitoring, Physiologic , Nerve Block , Organothiophosphorus Compounds , Oxygen , Perfusion , PuncturesABSTRACT
A pulse oximeter is used widely on account of its convenience and very few complications. We experienced a case of accidental burning by a pulse oximeter sensor. An 83-year-old woman underwent total hip replacement surgery. A pulse oximeter (Oxisensor II N-25, Nellcor Puritan Bennett Inc., USA) was placed on the left index finger. The patient complained of pain on her index finger 5 minutes after the operation began. A localized skin burn was found underneath the sensor of the pulse oximeter. The skin burn healed without any sequelae.
Subject(s)
Aged, 80 and over , Female , Humans , Arthroplasty, Replacement, Hip , Burns , Fingers , SkinABSTRACT
BACKGROUND: Acute hypoxia tolerance has been evaluated by the time of useful consciousness, subjective symptoms, cardiovascular changes, visual deterioration, psychological performance, and so forth. But these methods are either subjective, lacking strict objectivity, or too demanding to collect sufficient data. Pulse oximeter monitoring has come to be used not only in hospitals but in the aviation environment. This noninvasive oxygen monitoring apparatus warrants a highly objective analysis to investigate acute hypoxia tolerance. METHODS: Eight healthy male volunteers (20-25 years old) were exposed three times to a simulated altitude of 25,000 ft (7,620 m) at intervals of 7 days. We monitored arterial oxygen saturation (SaO2) and pulse rate by a pulse oximeter. The duration from taking the mask off to the time of 60% SaO2 was regarded as acute hypoxia tolerance. The venous hemoglobin concentration was measured a day before exposure to hypoxia. A questionnaire on the 14 subjective hypoxic symptoms was obtained after hypobaric chamber training. RESULTS: There were neither differences of acute hypoxia tolerance, hemoglobin concentration, nor pulse rate according to the repeated exposure of hypoxia. Four symptoms of sleepiness, fatigue, flushing and thinking impairment were sustained regardless of repeated exposures to hypoxia. But the incidence of symptoms of ear pain, anxiety, abdominal pain were reduced according to the repeated hypoxia. CONCLUSION: With pulse oximeter monitoring there was no difference between the values of time of 60% SaO2 in repeated exposures to hypoxia. The incidence of some subjective symptoms was reduced according to the repeated exposures to hypoxia.
Subject(s)
Humans , Male , Abdominal Pain , Altitude , Hypoxia , Anxiety , Aviation , Consciousness , Ear , Fatigue , Flushing , Heart Rate , Incidence , Masks , Oxygen , Thinking , Volunteers , Surveys and QuestionnairesABSTRACT
PURPOSE: A sentinel lymph node mapping with blue dye has been well accepted as a common procedure in breast cancer surgery. However, it is well known that blue dye absorbed into the circulation may interfere pulse oximetery reading. The aim of this study was to evaluate the change of pulse oximetery reading by isosulfan blue dye injection during sentinel lymph node mapping. METHODS: Thirteen breast cancer patients with normal preoperative cardiopulmonary functions were studied. Four ml of isosulfan blue dye was injected subdermally when the patient became stable after induction of general anesthesia. The pulse oximetery was monitored continuously. Multiple arterial blood gas analyses (ABGA) were performed before dye injection and 10, 30, 40 minutes after dye injection. The results of oxygen saturturation by oximetery (SpO2) and the results of arterial oxygen tension (SaO2) and arterial oxygen saturation (SaO2) by ABGA were compared. RESULTS: The value of both SaO2 and PaO2 measured by ABGA has not been altered by isosulfan dye injection. However SpO2 decreased by isosulfan dye injection. SpO2 decrease started 8.2+/-1.5 (2~0) minutes after dye injection and returned to preinjection level by 85.7+/-5.6 (60~126) minutes after injection. The lowest vaule of SpO2 was 95.6+/-1.2% (93~97). Mean duration of SpO2 decrease was 77.5+/-6.2 (40~117) minutes. The duration of SpO2 decrease was longer in the aged patients, but it was not statistically significant (p=0.3). There was no siginificant difference in duration of SpO2 decrease according to injection site, operation method, and body mass index (BMI). CONCLUSION: .Isosulfan dye injection using for sentinel lymph node mapping causes no change in true ABGA results but causes a mild reversible decrease in SpO2, It is important to look for other causes when SpO2 decrease is significant and persistent.
Subject(s)
Humans , Anesthesia, General , Blood Gas Analysis , Body Mass Index , Breast Neoplasms , Lymph Nodes , Oxygen , ReadingABSTRACT
A software system of the pulse oximeter is presented in this paper. Based on Franklin C, this software system includes three main parts, one part is to automatically regulates the base line of signal, the second part is a controlled integral module,and the third part is a digital signal processing module. As the result, the pulse oximeter is satisfactory to clinical monitoring.
ABSTRACT
BACKGROUND: Hypoxia often occurs during anesthesia of patients with tetralogy of Fallot (TOF). The factors that determine pulmonary circulation and oxygenation in patient with TOF are the degree of obstruction of right ventricular outflow tract (RVOT), right ventricular filling pressure, systemic vascular resistance, loss of negative pleural cavity pressure by thoracotomy, change of pulmonary vascular resistance due to positive pressure ventilation and degree of arteriopulmonary collateral connection. Hence pulse oximetry is a noninvasive technique for measuring arterial O2 saturation continuously, this study examined the correlation between the change of percutaneous arterial oxygen saturation (delta SpO2) and the change of mean arterial pressure (delta MAP) using pulse oximetry in these patients. METHODS: Twenty pediatric patients undergoing modified Blalock-Taussig shunt or total corrective operation were prospectively investigated. Immediately after induction, baseline values of MAP and SpO2 were determined and if there were some changes in SpO2 from baseline during operation, MAP on that value of SpO2 were collected. If SpO2 reduced, patients were treated with infusion of fresh frozen plasma or pentastach (2-10 ml/kg), injection of phenylephrine (10 microgram/kg) or esmolol (0.5 mg/kg). RESULTS: Intravascular volume loading only was executed in 4 patients, intravascular volume loading and phenylephrine administration was executed in 11 patients, and intravascular volume loading, phenylephrine and beta-blocker administration was executed in 5 patients. There were no significant correlation between delta MAP and delta SpO2 from linear correlation and regression analysis (r=0.23, p<0.05). CONCLUSIONS: Because delta SpO2 were not closely related with delta MAP and above mentioned factors could act closely among each others, meticulous anesthetic management is necessary during palliative or total corrective operation in patients with TOF.
Subject(s)
Humans , Anesthesia , Hypoxia , Arterial Pressure , Blalock-Taussig Procedure , Oximetry , Oxygen , Phenylephrine , Plasma , Pleural Cavity , Positive-Pressure Respiration , Prospective Studies , Pulmonary Circulation , Tetralogy of Fallot , Thoracotomy , Vascular ResistanceABSTRACT
This case showed that pulse oximeter was helpful for early detection of pulmonary edema during Cesarean section in a parturient woman with preoperative ritodrine treatment. Though arterial oxygen saturation ( Sp02 ) by pulse oximeter was low before the induction of anesthesia, the woman was anesthetized due to emergency situation. SpO2 was continuously low during the operation, so pulmonary edema was suspected. After the operaton, pulmonary edema was diagnosed on the chest x-ray. On the ECG, anteroseptal wall ischemia was detected. Supplementary O2 and diuretics therapy were performed. On the 3rd postoperative day, arterial blood gas analysis was within normal range. Four days after the operation, ECG was normalized and chest x-ray finding was much improved. 10 days later, chest x-ray finding was normalized.
Subject(s)
Female , Humans , Pregnancy , Anesthesia , Blood Gas Analysis , Cesarean Section , Diuretics , Edema , Electrocardiography , Emergencies , Ischemia , Lung , Oxygen , Pharmacology , Pulmonary Edema , Reference Values , Ritodrine , ThoraxABSTRACT
Introduction: Oxygen delivery to tissue is of major clinical interest in patients with cyanotic congenital heart disease (CHD). The use of pulse oximeter to monitor arterial oxygen saturation (SaO2) is considered accurate and reliable in the range of 90% to 100%. However with desaturation, the accuracy remains controversial below 90%. The aim of this study was to evaluate the accuracy of pulse oximetry in severe hypoxemia. METHOD: In 110 children with cyanotic CHD, pulse oximeter (N-200, Nellcor, USA) readings were compared with the direct measurement of SaO2 by blood gas analyser (Profile10, Stat, USA). All measurements were carried out after induction of anesthesia and devided into 4 groups according to saturation measured by pulse oximeter (SpO2). SpO2 in group I was higher than 90% (n=90), in group II between 80% and 89% (n=75), in group III between 70% and 79% (n=41), in group IV lower than 69% (n=18). Statistical analysis of paired SpO2 and SaO2 values was performed using correlation analysis and paired t-test. The other comparisons were perfomed with ANOVA. p<0.05 was considered statistically significant. RESULTS: Correlation coefficient of group I was 0.89 (p<0.01), group II was 0.67 (p<0.01), group III was 0.63 (p<0.01) and group IV was 0.41. The study demonstrate that SpO2 seems to have good correlation with SaO2 when SpO2 is higher than 70%. This results are contrary to other studies which show that SpO2 is not reliable when SpO2 is below 90%. However, the correlation value r seems to decrease with desaturation. CONCLUSION: The use of pulse oximeter in severe hypoxemic children with CHD is efficient in monitoring oxygenation, even though there is decrease in accuracy of the SpO2.
Subject(s)
Child , Humans , Anesthesia , Hypoxia , Heart Defects, Congenital , Oximetry , Oxygen , ReadingABSTRACT
Combining benzodiazepine with opioid has been used for analgesia and sedation during spinal anesthesia, but many authors have warned that combined administration of these drugs produces potent drug interaction that places patients at high risk for hypoxemia and apnea. This study was undertaken to observe the effect of combined use of diazepam with fentanyl on hemodynamic response and change in SaO in twenty healthy adult patients undergone elective surgery with spinal anesthesia. All of the patients were divided into the control and experimental group, and whom spinal anesthesia with 0.5% tetracaine the 12 mg and epinephrine 0.2 mg, were performed. To the control(Group I) and experimental group(Group 2) the combined dose of diazepam 0. 075 mg/kg with fentanyl 1 ug/kg, and diazepam 0.15 mg/kg with fentanyl 2 ug/kg, were given, respectively, by intravenous injection 1 hour after spinal anesthesia started. Blood pressure, heart rate and SaO2 of the two groups were compared at the time before administration of study drugs and 1 min, 2 min, 2 min, 4 min, 5 min, 10 min, 30 min and 60 min after administration of study drugs. The results were as follows. 1) SaO2 was significantly decreased in group 2 than Group 1 after study drugs were administed intravenously. 2) In both group, decrease in SaO2 was significant at the first 5 minutes after intravenous administration of study drugs. 3) SaO2 fell to 90% of the control value after the administration of study drugs in 6 patients of Group 2(60%). 4) Hemodynamic changes after intravenous administration of study drugs were statistically significant but not so clinically in both group. We concluded that combined intravenous administration of benzodiazepine and opioid under spinal anesthesia requires the careful monitoring of hemodynamic response and ventilatory status continuosly with those monitoring devices already in use and pulse oximeter. Availiability of skilled anesthesiologists for airway management and administration of supplemental oxygen are very important in combined intravenous administration of benzodiazepine and opioid.