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At least 649 records · Page 36Linked to original sources
PubMed1991

Nasoendotracheal tube obstruction secondary to inferior turbinate impaction.

This case report discusses one of the unusual complications of nasoendotracheal intubation, amputation of the inferior turbinate with its subsequent impaction of the nasoendotracheal tube. A healthy 19-year-old male underwent surgery for an open reduction and internal fixation of a fractured mandible. Several minutes after nasoendotracheal intubation, airway pressures increased, end-tidal carbon dioxide levels increased, and the patient became difficult to ventilate. The patient was extubated and then reintubated with a smaller-diameter nasoendotracheal tube through the same naris without further sequelae. After examination the tube was found to be occluded with an inferior turbinate. The increased airway pressure and elevated carbon dioxide levels were early signs of partial airway obstruction. Capnography was an important early warning device to provide information prior to changes in other vital signs. It allowed rapid detection of a potentially disastrous obstruction of the airway before the patient experienced severe cardiopulmonary complications. These facts should assist the anesthetist in focusing attention on the possible obstruction of the airway with a foreign body after nasoendotracheal intubation.

Adult↗
PubMed1991

The rationale for pulse oximetry and capnometry in anaesthesia and sedation.

The monitoring of sedated or unconscious patients always requires a trained clinician. Extra vigilance and information can be provided by numerous electronic aids that also introduce error, distraction and cost. Particularly for pulse oximetry and capnography, however, these negative factors are offset by the benefits of accurate blood-gas information obtained continuously and non-invasively. The photometric principles common to pulse oximetry and infrared capnometry are examined in detail. Accuracy and sources of error are discussed and applications and limitations outlined. Evidence of the beneficial impact of these two instruments is presented from published experience with both unconscious and sedated patients.

Anesthesia, Dental↗
PubMed1991

[Mechanisms of pulmonary ventilatory function disorders and methods of their correction in acute bronchiolitis in infants].

Rearrangement of ventilatory diffusion of gases in the end parts of bronchioles was detected by transcutaneous monitoring and capnography in 32 children aged 2 to 8 months afflicted with acute bronchiolitis. It consisted in a decrease of CO2 elimination from the alveolar air (to 2.8% against 4.5% in health) and in moderate deviations of O2 diffusion. Sessions of spontaneous respiration under positive pressure with O2 concentration not higher than 40 v% turned out the most effective therapeutic method to recover the deviations in question.

Acute Disease↗
PubMedDate not supplied

[New clinico-therapeutic directions in upper airway pathology].

The main issues regarding the pathology of the primary airways in children, such as persistent rhinitis, recurrent disease of the pharynx and laryngitis, have been re-examined and updated on the basis of the latest findings regarding immunology and respiratory physiopathology as well as recent technological progress in the field of diagnosis. As far as rhinitis is concerned, recently demonstrations that nasal mucosa, like bronchial mucosa, responds to different kinds of stimuli with the same type of inflammation, have led to a new nosographic viewpoint: apart from classic allergic rhinitis, multifactorial forms are now recognised. They have been defined as nonallergic persistent rhinitis having a particular subgroup: nonallergic rhinitis with eosinophils. The fact that different factors contribute to bringing about the same inflammatory process is also confirmed by a personal study carried out on 132 asthmatic children with rhinitis: the results showed, in fact, that there are no differences regarding the nasal mucosa of allergic children (positive prick) and nonallergic children (negative prick). This observation therefore diminishes the importance of rhinoscopy in the etiologic diagnosis of rhinitis. As far as the obstructive syndrome caused by adenotonsillar hypertrophy is concerned, extremely polymorphic clinical pictures can be identified: from the slightest nocturnal hypoventilation to the apnea syndrome during sleep, even to the most severe forms with cardiocirculatory insufficiency. Personal data on 42 children helped to define both the anamnestic and objective findings necessary for making the diagnosis. It was therefore found that the most indicative and specific observations were those made either by the mothers (heavy breathing noises) or by the physician (inspiratory retractions) while the children were sleeping. Clinical data are therefore usually sufficient for making the diagnosis; however, in the first two years of life, a period in which surgical operations are usually delayed if possible, it is necessary to make an instrumental evaluation of the degree of hypoventilation. By means of radiological examination, pharyngoscopy and capnography, it is possible to record the degree of obstruction and therefore decide whether or not to delay surgery. Apart from the obstructive respiratory syndrome with hypoventilation, that requires surgery at all costs, other conditions were examined that can profit by adenoidectomy, such as affections of the middle ear, chronic sinusitis and craniofacial dysmorphisms. As far as laryngitis is concerned, the importance of radiology and endoscopy in rapidly diagnosing epiglottic laryngitis is reported. This in turn sometimes facilitates quick pharmacological treatment so as to avoid more invasive interventions, such as tracheostomy.

Adenoidectomy↗
PubMed1990

[Blood gas disorders during one lung ventilation and the efficacy of the monitors].

The incidence and the causes of the abnormal blood gas levels were analysed with 188 patients who had one lung ventilation during general anesthesia, and the monitors to detect such complications were discussed. Abnormal blood gas levels were detected in 47 patients (25%), and 6 of 47 patients had dislocation of endotracheal tube or cuff. There was one patient who suffered from severe blood gas disorder due to the total occlusion of trachea by cuff herniation. Forty one cases (41.8%) had abnormal blood gas levels even though there was no dislocation of endotracheal tube or cuff. In these patients the blood gas abnormalities were mild and transient. These data suggest that mild blood gas disorders were relatively easily detected with pulse oximeters and capnography. However, serious disorders were not detected with these monitors if the anesthesiologists were not familiar with these equipment.

Adolescent↗
PubMed1990

[Disorders of hemodynamics and pulmonary gas exchange in the acute period of myocardial infarct].

In 40 patients with massive myocardial infarction, the central hemodynamics was examined by probing the right-sided chambers of the heart and the pulmonary artery. The cardiac output was measured by thermodilution. The gas exchange (respiratory minute volume, capnography, gas analysis of arterial and mixed venous blood) was explored. Arterial hypoxemia was found to be associated with increased intrapulmonary blood shunting in patients with acute myocardial infarction complicated by congestive heart failure. Deterioration of arterial hypoxemia was promoted by a combination of increased overall pulmonary shunting and decreased residual venous oxygenation. Abnormalities in the ventilation-perfusion relations are of great importance.

Aged↗
PubMed1990

Clinical evaluation of pulse oximetry monitors on critically ill patients.

Four pulse oximeters and two pulse oximeter-capnographs were evaluated on accuracy of measuring oxygen saturation and heartrate for the former and oxygen saturation, heartrate, respiratory rate and capnography for the latter. In the first part of the study four pulse oximeters (Criticare Systems Model 501 +, Ohmeda Biox 3700 Pulse Oximeter, Nellcor Model N 100 and Datex Satlite) were simultaneously studied on 10 ventilated ICU patients. Fifty simultaneous measurements were done for heartrate and oxygen saturation and compared to arterial saturations and ECG heartrates. Mean differences from pulse oximeter values versus control arterial and ECG values were within two percent for the four instruments. In the second part two oxicaps (Ohmeda 4700 and Nellcor N 1000) were evaluated with the same control parameters. Thirty measurements on 3 patients were done. As in the first part of the study all results were accurate within two percent of control values. From those data we can conclude that all examined monitors were fairly accurate compared to simultaneous arterial blood gas analysis and ECG monitoring. The oxicap monitors have the advantage of giving continuous information on two very important parameters of patient monitoring: CO2 and saturation.

Adult↗
PubMed1989

[Intraoperative detection of air embolism and corpuscular embolism using pulse oximetry and capnometry. Comparative studies with transesophageal echocardiography].

19 patients undergoing total hip replacement in general anesthesia because of transcervical femur fractures were continuously monitored throughout surgery to detect any embolic events. Aside from the standard monitoring with ECG and control of arterial pressure in regular short intervals, the pulse-oximetry and capnography were applied for a comparative examination of their sensitivity in detecting gas and corpuscular embolisms. Transesophageal echocardiography (TEE) which allows an extensive assessment regarding the extent and differentiation between gaseous and corpuscular embolisms was chosen as a reference method. The examination concentrated on the implantation of the acetabulum and femur prosthesis since this phase of the operation has been associated with a high incidence of embolisms. The TEE monitoring revealed corpuscular as well as gaseous emboli during surgery. In the 36 cases of echocardiographic detectable embolisms prospectively defined changes of the heart rate were observed in 17%, of the mean arterial pressure in 56%, of the end-expiratory CO2 partial pressure in 47% and of the arterial O2 saturation in 31% of the cases. The embolisms which had been categorized by means of TEE according to their severity reflected a decrease of the end-expiratory CO2 partial pressure in 25% of the cases with light, in 45% of the cases with moderate and in 69% of the cases with severe embolisms, whereas a decrease in arterial O2 saturation was detected in 8% with light, 27% with moderate and in 54% of the cases with severe embolisms. Corpuscular embolism had no stronger influence on the frequency of relevant changes of end-expiratory CO2 partial pressure and the arterial O2 saturation than did the gaseous emboli.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

[Noninvasive monitoring].

For a number of reasons, invasive and non-invasive measuring procedures for monitoring purposes must not be considered to be mutually exclusive alternatives. The transitions between the two are fluid, and their respective advantages and disadvantages frequently complement one another. The complication rate characteristic of a given procedure is the greater, the more invasive this procedure is. For this reason, a non-invasive technique should always be given preference over an invasive method provided it is capable of recording the parameter to be monitored at least as reliably and accurately as the latter. For minimal monitoring during anaesthesia, non-invasive procedures are applied exclusively. These include the monitoring of ventilation (FIO2, pressures, volumes, flows), ECG, measurement of blood pressure employing the cuff method, temperature measurement, and a nerve stimulator for establishing the degree of relaxation. In addition, pulse oximetry and capnography are increasingly becoming accepted elements of basic monitoring. The question as to whether further monitoring procedures need to be employed will depend upon the condition of the patient and the nature and duration of the surgical operation and anaesthesia. Here, preferential use is made of invasive methods of recording pressures and flows (cardiac output) within the circulatory system and of various blood parameters (for example, blood gas analysis). To an increasing extent, they are being supplemented, expanded or replaced by newly developed non-invasive methods. Thus, for example, the time and material requirement for non-invasive blood pressure measurement in the finger by means of servomanometry (Finapres) is reduced as compared with intra-arterial pressure recording.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, General↗
PubMed1989

[Non-invasive methods of respiratory monitoring during resuscitation in neonatal and pediatric care].

The authors review the non-invasive methods currently used in paediatric intensive care units to monitor the oxygenation and ventilation of neonates and infants. They deal successively with the qualities and defects technique (transcutaneous measurement of PO2, SaPO2 and PCO2) and with the usefulness of capnography. These various methods of investigation and monitoring must complete each other to ensure the safety of children in situations of distress.

Blood Gas Monitoring, Transcutaneous↗
PubMed1988

Anesthesia for cesarean section: minimizing risk and complications.

Managing cesarean section anesthesia is challenging and fraught with hazards. Each anesthetic option has different maternal and fetal risks. Emphasis on regional anesthesia when possible and utilization of state-of-the-art monitoring such as pulse oximetry and end-tidal capnography will improve the anesthetic outcome.

Anesthesia, Epidural↗
PubMed1986

[Measurement of end-expiratory carbon dioxide values in pediatric anesthesia].

This study dealt with two principles of the evaluation of end-expiratory CO2 in pediatric anaesthesia: detection of CO2-influenced infrared rays with a full stream analyzer attached to the tracheal tube; CO2 measurement with a side-stream analyzer connected to the breathing and ventilating system by a small tube. The linearity of the analyzers was tested with gas mixtures containing 3.0/5.0/7.0 vol% of CO2 cycling at an increasing rate. Additional mass-spectrometry has proven that the instruments are accurate within the clinical range of pediatric anesthesia. A maximal deviation of 8% develops when cycling rates increase to 40 per min. To detect quality differences in the analyzers, tangential constructions onto the CO2 curves plotted by the capnographs provided valuable quotients. Depending on the length of the tubing that feeds samples of respiratory gas into the side-stream analyzer, the CO2 curves were subject to sinus degradation with increasing respiratory rates. Capnography with full-stream analyzers depended on inspiratory zero CO2 content for reference purposes.

Anesthesia↗
PubMed1986

Ventilatory changes during nitrous oxide isoflurane anaesthesia in children.

The changes in ventilatory variables under nitrous oxide isoflurane anaesthesia were studied in 10 children (mean age 46 +/- 13.4 months, mean weight 16.2 +/- 2.1 kg). Measurements of flow and volume were performed by pneumotachography. PE'CO2 was measured by capnography. The following variables (VE, VT, TI/TTOT, VI, PE'CO2) were measured or calculated under three increasing inspired isoflurane concentrations (0.75%, 1.5%, 2.25%). At each level of anaesthesia, ventilatory changes during exposure to an inspired CO2 fraction of 2% were studied. The increase in the inspired concentration of isoflurane was associated with a decrease in alveolar ventilation. PE'CO2 increased significantly with increasing depth of anaesthesia. The respiratory rate was slightly increased under light nitrous oxide isoflurane anaesthesia, but no further changes were observed with increasing depth of anaesthesia, although the children were breathing a mixture of nitrous oxide and oxygen. The ventilatory response to a raised inspired CO2 is markedly decreased under light nitrous oxide isoflurane anaesthesia, and decreases significantly with increasing depth of anaesthesia. In response to a raised CO2, VE, VT and VI increase, but respiratory rate decreases or remains constant and TI/TTOT is unchanged.

Anesthesia↗
PubMed1987

Ventilatory CO2 response, respiratory drive and timing in children anaesthetized with halothane, enflurane or isoflurane.

Ventilatory CO2 response, respiratory drive and timing were investigated during anaesthesia prior to surgery in 24 spontaneously breathing cardiopulmonary healthy children. Anaesthesia was maintained with halothane, enflurane or isoflurane combined with oxygen-nitrous oxide (FIO2 0.5). The MAC values were 0.97 for halothane, 0.92 for enflurane and 0.92 for isoflurane. Pneumotachography and capnography were used and airway pressures were measured before and during breathing of 4% CO2 as well as during airway occlusion. Changes in minute ventilation were less with enflurane than with halothane and isoflurane in response to 4% CO2; however, tidal volumes were equally increased with all three agents. End-tidal CO2 tensions were significantly higher during enflurane than during both halothane and isoflurane anaesthesia, before as well as during CO2 stimulation. Respiratory rates were lower in children anaesthetized with enflurane and were unresponsive to CO2 when all three volatile agents were used. During CO2 challenge, mean inspiratory flow and maximal occlusion pressure were similarly increased in all groups.

Airway Resistance↗
PubMed1988

Noninvasive carbon dioxide monitoring.

Technical aspects and clinical applications of the two most commonly used noninvasive CO2 monitors, capnography and transcutaneous monitoring, are discussed. Neither accurately reflect PaCO2 in most critically ill patients. However, both monitors give valuable information about other aspects of the patient's physiology. PETCO2 reflects changes in pulmonary perfusion and deadspace ventilation; and, PtcCO2 reflects changes in peripheral perfusion. Thus, both are useful in the critically ill patient, but not necessarily for the assessment of PaCO2.

Blood Gas Monitoring, Transcutaneous↗
PubMed1986

[Patient monitoring during anesthesia].

Three functional levels are monitored during anaesthesia: vital functions such as cardiovascular and respiratory systems; metabolic functions; and organs such as brain and muscle. These three levels interact with each other and with the anaesthesia system. Basic monitoring systems include the ECG, noninvasive blood pressure measurement, inspired O2 concentration, tidal volume, airway pressure, and alarm systems for stenosis and disconnection. Other monitors are added to this list, including pulse oximetry, capnography, temperature, and neuromuscular transmission. The type of surgery and anaesthetic risk will determine the extent of the monitoring used during surgery. New and expensive noninvasive monitoring techniques such as transesophageal Doppler echocardiography and somatosensory evoked potentials will increasingly be added. The high costs and the rising number of monitoring systems necessitate a better definition of what is essential and what is optional for each individual case.

Anesthesia↗
PubMed1979

[General anesthesia in infants].

It is generally accepted, that the progress in surgical treatment of congenital malformation is closely related to the progress in highly-specialised methods of newborn anaesthesia. The safe methods of anaesthesia have to be adapted to anatomical and physiological peculiarities of the earliest days of life as well as to different reaction to drugs and anaesthetics. The preoperative preparation in newborns used to be often very short, because most of the problems of the neonatal period are emergency surgical interventions and there is no time for treatment even of the serious disturbances of basic physiological functions. The purpose of this study was to estimate methods of general anaesthesia in newborns, which have been introduced in the Anaesthesiology Department of the National Research Institute of Mother and Child. The main element of these methods was general anaesthesia with muscle relaxants and controlled ventilation as a routine. The estimation was based on general analysis of 10 years practice when these methods of anaesthesia were used. During this time 515 anaesthesias to 408 both-sex newborns were given (Tab. I, Fig. 1). 85% of anaesthetized newborns were operated because of congenital malformations (Tab. I); 46% of operations were performed during their first week of life, 21% were operated in first 24 hours of life, mostly as an emergency (Fig. 3). 10% of operations were performed is prematures (body weight below 2500 g) (Fig. 4). The "routine" anaesthesia was given in 82% cases. Awake intubation in unpremedicated newborns was performed. Anaesthesia was maintained with nitrous oxide-oxygen mixture (1:1 or 2:1). D-tubocurarine in 95% of cases was used. The initial dose 0,5 with matures and 0,25 mg with premature babies was used. If necessary supplementary doses were given. During anaesthesia, intermittent positive pressure ventilation (IPPV) with frequency at least 60/min. was used. During this ventilation, hyperventilation and positive end-expiratory pressure (PEEP) were obtained. Precordial stetoscope and thermometer probe was used as a routine. In some special cases eCG, end-expired CO2 (capnography), pletysmography were also recorded; blood gas analyses were checked. All intra- and postoperative complications as well as postoperative mortality have been analysed in details. During 3,3% of operations some complications had been observed. The total incidence of early psotoeprative complications was 20%. In this group the most frequent were respiratory complications (16,1%). Serious disturbances in pulmonary gas exchange during operation and early postoperative period were not found.(ABSTRACT TRUNCATED AT 400 WORDS)

Anesthesia, General↗
PubMed1979

Periodic respiration. The capnographic interpretation.

Different type of periodic respiration are difficult to distinguish clinically although their identification may influence the diagnosis, prognosis and treatment. Often other forms of abnormal respiration are mistaken for periodic. Four capnograms are shown illustrating (1) true Cheyne-Stokes respiration, (2) irregular "pseudo-periodic" respiration a) after fentanyl, and b) in the presence of a brain tumour and (3) regular respiration interspersed with deep sighs which was diagnosed clinically as Cheyne-Stokes respiration. A plea is made for the routine use of capnography in order to provide a visual record of respiration.

Carbon Dioxide↗