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Capnography as the graphical representation of the expiratory carbon dioxide (CO2) concentration, is an essential component of monitoring of every ventilated patient, in addition to pulse oximetry. Capnography demonstrates the kinetics of CO2 in a noninvasive way and in real time. In the daily routine anesthesia, it mainly serves for identification of the correct intubation and adaptation of the respiratory minute volume to be applied; however, capnography can also provide much more far-reaching and clinically particularly valuable information, especially in the form of volumetric capnography (VCap) that is not yet so widely clinically available. These include monitoring and optimization of ventilation and assessment of gas exchange. This article presents parameters for making decisions at the bedside, which could previously only be obtained by extensive, more invasive, nonautomated procedures. [ABSTRACT FROM AUTHOR]

Capnography is the graphical representation of the carbon dioxide (CO2) concentration in expired air. Using this monitoring procedure, the kinetics of CO2 of mechanically ventilated patients can be assessed in a noninvasive way and in real time. This article highlights the importance, particularly of volumetric capnography (VCap), for clinical monitoring of mechanically ventilated patients. The procedure provides important information on the breathing, ventilation, metabolism and hemodynamics of patients. [ABSTRACT FROM AUTHOR]

Chiari malformation type I (CM I) shows a high prevalence of sleep-related breathing disturbances (SRBDs). These can be of obstructive origin or due to impaired respiratory control. Pathophysiological causes are insufficiently evaluated. Randomized controlled studies for SRBD therapy in CM I do not exist. We describe a case of severe, predominantly central sleep apnea due to increased carbon dioxide chemosensitivity, which was treated successfully with adaptive servoventilation. [ABSTRACT FROM AUTHOR]

Background: In various fields of medicine the transcutaneous measurement (pCO) of carbon dioxide pressure (pCO) has been accepted as a reliable measuring method while for other disciplines the method has been doubted. Nevertheless, some minor therapeutic interventions, such as electroconvulsive therapy and breathing biofeedback used in psychiatry could benefit considerably from transcutaneous monitoring. The study presented here investigated the accuracy of transcutaneous measurement as compared to end-tidal (pCO) and capillary (pCO) measurements in hyperventilation. Methods: In this study 22 healthy volunteers underwent a hyperventilation procedure with assessment of pCO, pCO, pCO, breathing and pulse rates. The three measurement methods of pCO were compared pairwise by Bland-Altman diagrams before and at the end of hyperventilation. The time delay between pCO and pCO was determined for each individual participant by a stepwise shifting the time course of pCO until an optimal congruence with pCO was reached. Results: The study group consisted of 10 men and 12 women with a mean age of 30.5 ± 9.4 years. The experimental procedure lasted an average of 27.7 min including 1.9 min for the baseline measurement and 11.6 min for the actual hyperventilation procedure. The course of pCO from baseline to the end of the hyperventilation phase and back to normal baseline followed a U-curve in all individuals. The pCO could be reduced by a mean of approximately 45 % for the 3 measurement methods from the individual baseline of 35 mmHg. The breathing and pulse frequencies increased by 26.8 % and 17.3 %, respectively. A total of 91 pCO values (mean 4 values per person) and 1,218 pairs of pCO and pCO values (mean 55 values per person) could be evaluated. The difference of the pCO values for two measurement methods revealed similar standard deviations in the Bland-Altman diagrams of about 2.5 mmHg for the 3 pairwise comparisons. The absolute measurement differences between pCO and pCO, pCO and pCO as well as pCO and pCO were averaged for each single participant and afterwards across all individuals resulting in values of 2.0, 2.5 and 2.3 mmHg, respectively. When the baseline and hyperventilation periods were examined separately in this analysis they did not show any relevant differences. The individually determined delays of pCO in regard to pCO averaged 53 s. The time delay exceeded 1 min in only two study participants. Conclusions: In the presented hyperventilation experiment the agreement between the pCO values and the pCO and pCO measurements were comparable to the agreement between the latter two. Altogether, the comparability of the measurement methods seemed satisfactory. The delay between the time courses of pCO and pCO of <1 min for most participants was short and is acceptable for clinical practice. Because only healthy subjects were tested these results might not be the same in children and critically ill patients and could differ from the presented results. [ABSTRACT FROM AUTHOR]

In healthy subjects, respiratory regulation adapts alveolar ventilation to metabolic carbon dioxide production. A dysproportional decrease in alveolar ventilation after sleep onset with a consecutive rise in arterial carbon dioxide partial pressure is called sleep-related hypoventilation, which usually coincides with longer lasting arterial oxygen desaturation. Limits of normal pCO values during sleep in the literature are inconsistent. The International Classification of Sleep Disorders (ICSD-2) distinguishes five types of sleep-related hypoventilation. As pathophysiological mechanisms, 'central' mechanisms, caused by impairment of central nervous regulation of respiration are differentiated from 'peripheral' mechanisms, caused by medical or neurological conditions. The diagnosis is based on the detection of hypercapnia. Taking into account the methodological limitations, this can be done using transcutaneous or end-tidal pCO measurements. [ABSTRACT FROM AUTHOR]

Breathing is part of a transport system that serves gas exchange of the body. Rhythmic breathing movements are controlled by the neuronal respiratory network in the medulla oblongata, which is dependent on tonic afferents. These are partly closed feedback loops to guarantee the homeostasis of blood gases and acid-base balance, and partly non-feedback stimuli as the so-called 'wakefulness drives.' Orexinergic neurons in the hypothalamus seem to play an important role in the tonic drive of respiration during wakefulness. Sleep onset markedly reduces tonic afferents, decreases the sensitivity to hypoxia and hypercapnia, and elevates arousal thresholds. Sleep unmasks the apnea threshold. If the arterial carbon dioxide partial pressure drops below this threshold due to short hyperpneic episodes, the respiratory rhythm arrests. Restless sleep with frequent changes in sleep states destabilizes the breathing pattern. The muscle atonia especially during REM sleep also affects the upper airway muscles and the intercostal muscles. Consequently, there is an increase in airway resistance. The diaphragm has to compensate these challenges by increased work. Nevertheless, in healthy subjects the blood gases only slightly change from wakefulness to sleep. [ABSTRACT FROM AUTHOR]

With the assistance of digital pen and paper technology in the field of prehospital data reporting, it seems to be possible to fulfill the requirements of „documentation“ as well as the requirements of „quality management“. The aim of this study was to determine the „primary documentation quality“ (PDQ) of a data reporting system based on digital pen and paper technology (so-called DINO) within a helicopter emergency medical service (HEMS) over a 6-month period. The PDQ is defined as the proportion of prehospital documented data, which is primarily recorded correctly by the data reporting system. For the national uniform core dataset (so-called MIND2) the PDQ was 96.7%, for „checkbox“ and „numeric data fields“ the PDQ was 99.8% and 93.6%, respectively and for „vital data“ the PDQ was 96.7% [heart rate (HF), measurement of blood pressure] and 84.1% [peripheral oxygen saturation (SpO2), end tidal carbon dioxide concentration (etCO2), oxygen administration (O2)]. For „measurements“ the PDQ was 96.9% (time stamps) and 86.9% (time frames), for „drugs“ the PDQ was 43.6% (drug name) and 69.8% (drug dosage) and for“placement of infusion” 42% (infusion name) and 85.3% (infusion time), respectively. The average time for the „verification process“ after mission completion was 1.5±0.4 min/mission. The „primary documentation quality“ of prehospital mission data reporting with the assistance of a digital pen and paper based documentation system (DINO) has been shown to completely fulfill the requirements of rapid and safe data documentation in actual missions, even at this early stage of development. [ABSTRACT FROM AUTHOR]

In the case presented problems with mechanical and manual ventilation of a patient occurred during the operation. Prior to this endotracheal intubation had been performed without difficulty and the respirator had passed all system checks. A leakage in the recently changed carbon dioxide absorber could be detected which had been accidentally dropped and damaged internally. [ABSTRACT FROM AUTHOR]