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F Mertzlufft

Publications and source records attributed to F Mertzlufft.

At least 19 recordsLinked to original sources

[Accuracy of measurement and overestimation of CO2 of two capnometers intended for potential use in emergency medicine].

UNLABELLED: Capnometry, the noninvasive measurement of end-expiratory CO2 concentration (cCO2, vol%) or calculation of its respective partial pressure (pCO2; mmHg) is an established method. However, for prehospital settings, capnometry is still used very restrictively, mainly owing to the respective devices used. The prerequisite for their use is sufficient accuracy (+/-2 mmHg) and easy handling. Two special capnometers (STAT CAP. Nellcor: mainstream, semiquantitative estimation; Capnocheck 8200, BCI: sidestream, quantitative measurement, numeric display), developed recently for potential use in emergency medicine, are said to fit these criteria. Therefore, the objective of the present investigation was to assess the accuracy and precision of both devices, comparing methods under standardized in vitro (reference gases) and in vivo (intubated and ventilated patients) conditions. METHODS: Both devices ("STAT CAP": pCO2 range, light bars; "Capnocheck 8200") were evaluated regarding the accuracy of pCO2 (Capnocheck) and the precision of the CO2 range (STAT CAP). Tests were performed with four dry gas mixtures (STPD) of defined composition and during ventilation of 20 intubated patients (BTPS). All measurements were compared with the alveolar gas monitor "AGM 1304" (Brüel & Kjaer, Denmark) as a reference method with a proven +/- 1 mmHg accuracy of pCO2 measurement. RESULTS: The "Capnocheck" (BCI) presented an accuracy of the pregiven pCO2 of 0.7-1.4 mmHg (dry gas mixtures, STPD) and an overestimation of 0.2 +/- 4.1 mmHg (BTPS) during ventilation with pure oxygen; inaccuracy during ventilation with 70% N2O in O2 proved to be + 1.2 +/- 1.7 mmHg (BTPS). Nellcor's "STAT CAP" failed to reach the target value in 10% of analyses, as shown by the respective segment bar of the display. CONCLUSION: Evaluation of the accuracy of capnometers must focus on the necessary pH2O correction and the possible effects exercised by O2 (and N2O) as well as the possible dependence on barometric pressure (if pCO2, mmHg, is the desired value). The "Capnocheck" showed an accuracy of more than 2 mmHg in dry gas mixtures as well as in humidified air. Concerning the practical use during constant artificial ventilation, the digital display and accuracy of the sidestream capnometer allow for reliable conclusions on patients' ventilation and circulation (CO2 elimination). The 90% accuracy of the segment bar display of Nellcor's "STAT CAP", per se covering only a rather broad range of 20 mmHg, obviously does not provide more than a rough overview. Therefore, the STAT CAP cannot be recommended for prehospital capnometry in the field. However, both the accuracy of the BCI capnometer (Capnocheck) and its numeric display and easy handling strongly recommend this device also for clinical use.

Blood Gas Analysis

[Life threatening anaphylaxis after repeated cisplatin administration: case report and neu therapy concepts].

The present case reports of a 58-year-old female patient presenting with severe (III degrees) anaphylactic reaction due to repeated chemotherapy with Cisplatin. After resection of the advanced ovarian carcinoma the patient was presented with complaints of itching, angioneurotic edema and dyspnea in 1990 when Cisplatin had been infused for the first time. Due to relapse after four years a further operation was performed and as much of the tumour as possible was resected. Then again, Cisplatin was applied. Cortisone, H1- and H2-blockers were given prior to its application increasing the tolerance of treatment. Subsequent treatment with further Cisplatin infusion, however, resulted in severe anaphylactic shock with dyspnea and cold sweat. Emergency treatment included application of pure oxygen, two large i.v. cannulas, and 1.5 l of crystalloid, and 0.5 l of colloids (Gelafundin). Additionally, a potent vasoconstrictor (Akrinor) and 750 mg Methylprednisolone were given. Symptoms improved as blood pressure normalised, and the patient felt much better 20 minutes later. In summary, the present case report proves that anaphylactic shock induced by Cisplatin demands interdisciplinary action. This particularly applies to the interval between occurrence of the first shock signs and arrival of the emergency team.

Anaphylaxis

[Apnoeic oxygenation in Boerhaave syndrome].

UNLABELLED: Boerhaave's syndrome (Hermann Boerhaave, 1724 [5]) stands for the atraumatic spontaneous rupture of the oesophagus, and still represents a life-threatening situation. Contrary to the surgical approach, the anaesthesiological management has been largely neglected so far. CASE REPORT: The present case report introduces a patient requiring surgical therapy due to a belatedly diagnosed rupture of the oesophagus. In agreement with the surgeon, endotracheal intubation was performed using a single-lumen oral Woodbridge tube. During left thoracotomy, artificial ventilation sometimes obstructed the surgeons. Following a life-threatening intrathoracic venous bleeding (after additional right thoracotomy), the situation became almost adverse, since the surgeon could not stop the bleeding due to the movement of the lungs. Ventilation was therefore stopped. The oxygen supply was provided 20 min by application of the so-called apnoeic oxygenation, first described in 1908 by the German surgeon Franz Volhard (15). Using the filled 2.5l reservoir bag of the circle circuit as the oxygen source (CPAP 10 cm H2O), oxygenation was maintained by refilling the bag after its volume had been decreased due to the patient's ongoing O2 consumption. Starting with an initial paO2 value of only 400mmHg (despite pAO2 approximately 670 mmHg, i.e. intrapulmonary right-left shunt of approx. 10-15%), the paO2 declined to 100 mmHg during the 20 min of apnoeic oxygenation (i.e. a drop by 15 mmHg per minute), whereas arterial pCO2 increased by 50 mmHg to a value of 90 mmHg, as stated recently in literature [18]). No relevant changes of ECG, heart rate, blood pressure and partial arterial oxygen saturation (pulse oxymeter) occurred. CONCLUSION: During thoracic operations adverse situations may arise from the two antipodes artificial ventilation and acceptable surgical access. Alternative respiratory techniques, e.g. one-lung anaesthesia and/or high-frequency jet ventilation, are not always applicable, although the present case report indicates that a double lumen tube should be recommended. However, the clinical use of oxygenation by apnoeic oxygenation is a useful measure that can be realised in a simple and safe manner. The present case report may help to consider this particular alternative also during thoracic surgery (no influence of FRC size on pAO2 decrease). If applied correctly, apnoeic oxygenation obviously increases both the flexibility of the anaesthesist and patient safety, and additionally provides the ability of safe acting in clinical routine settings as well as during emergencies. In summary, knowledge of this technique of oxygenation seems to be an integral part of serious anaesthesiological education and clinical management.

Esophageal Diseases

[Gamma-hydroxybutyric acid--significance for anesthesia and intensive care medicine?].

Gamma-hydroxybutyric acid (GHB) as a natural component of the mammalian brain was first introduced in clinical anaesthetic practice more than 30 years ago. Although GHB induced a reliable state of sedation and anaesthesia without depressing either respiratory or cardiocirculatory parameters or liver and kidney function, the drug was nearly displaced from clinical practice because of its prolonged duration of action. The results of recent clinical studies indicate a re-evaluation of GHB in emergency and critical care medicine. GHB is regarded as a natural neuronal transmitter with circuits which synthesise, accumulate and release GHB. Specific binding sites have also been demonstrated and identified. GHB is completely metabolized in the liver to the natural substrates carbon dioxide and water without accumulation in central or peripheral tissues. The reduction of energy metabolism and its possible properties as an "oxygen radical scavenger" may be of therapeutic benefit if tissues are exposed to hypoxia or reperfusion. Therefore, the application of GHB seems to be of advantage in states of traumatic brain injury with cerebral oedema or ischaemic lesions of brain or extraneural tissues. In hypovolaemic states or in patients with impaired cardiovascular function, the pressure effects of GHB may be beneficial for the prevention of tissue damage and may improve survival in the case of cardiocirculatory resuscitation. In the intensive care unit, GHB might be a favourable alternative to established sedative agents. Occurrence of side effects such as tolerance and withdrawal syndromes after the application of sedative drugs, an impaired metabolism with the accumulation of metabolites in the case of liver or kidney dysfunction as well as an insufficient regulation of natural sleep may be diminished by the application of GHB. The results of various clinical studies also suggest that GHB may be useful in the treatment of alcohol and opiate withdrawal syndrome. However, further studies are necessary to specify the proposed indications of GHB in anaesthesiology and critical care medicine.

Anesthesia, Intravenous