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P Lemberger

Publications and source records attributed to P Lemberger.

12 recordsLinked to original sources
PubMed2006

[Evaluation of CVC-set].

OBJECTIVE: Frequently central venous catheter sets do not contain all necessary materials. To evaluate, if combined measures using a specially arranged central venous catheter (CVC) set result in economical and clinical advantages, we compared both cost and time differences of a CVC complete set with ECG guide wire lead and an adhesive fixation with a standard set requiring additional materials, ECG fluid column lead and surgical suture. Furthermore, quality of different ECG leads, the reliability and tolerability of the adhesive fixation was compared. METHODS: 76 elective adult surgical patients were randomly assigned to receive either a control CVC set or a test CVC complete set, which was featured by preconnected stopcocks, included sterile drapes, guide wire ECG position control, and an adhesive fixation. We performed ECG-guided placement of the central venous catheter using a guide wire lead in the test CVC set vs. fluid column lead in the control CVC set. Time was recorded for preparation phase of the nurse and the anesthetist, for the puncture phase, for the ECG position control and time for CVC fixation. Quality of ECG position control using guide wire or fluid column was determined by forming Pmax/R ratio. Costs of the complete set and the standard set with additional material were compared. RESULTS: Times for preparation of nurse and anesthetists, for ECG position control and catheter fixation were significantly shorter using the test catheter set and resulted in a total time saving of 6 min (P < 0.01). Times for sterile preparation and central venous puncture were not significantly different between the groups. ECG position control using the guide wire was successful in 37 out of 38 patients (97%) and in 34 of 38 patients (89%), respectively. Pmax/R ratio was 0.8 +/- 0.2 using the guide wire versus 0.5 +/- 0.2, respectively. There were only 2 out of 38 adhesive fixations, that had to be replaced, while the mean duration of adhesive fixation was 6.2 days (3-15 days). Avoidance of disposable materials in the test CVC set led to a significant reduction of costs compared to the control CVC set. CONCLUSION: The test CVC complete set allows a significant time saving and cost reduction in performing a central venous catheter line because of completely included disposable materials. CVC position control via guide wire needs less time and shows significantly better quality of ECG compared to fluid column ECG lead. An adhesive revealed to be a reliable CVC fixation comparable to a surgical suture.

Adhesives↗
PubMed2004

Central venous catheter placement: comparison of the intravascular guidewire and the fluid column electrocardiograms.

BACKGROUND AND OBJECTIVE: Placement of central venous catheters in patients is associated with several risks including endocardial lesions and dysrhythmias. Correct positioning of central venous catheters in the superior vena cava is essential for immediate use. The objective of a first study was to evaluate the signal quality of an intravascular electrocardiogram (ECG) during position control using a guidewire compared with the customary fluid column-based ECG system, and to assess its efficacy of correct placement of the central venous catheter. A second study tested if dysrhythmias can be avoided by intravascular ECG monitoring during catheter and guidewire advancement. METHODS: The jugular or subclavian vein of 40 patients undergoing heart surgery or who were being treated in the intensive care unit was cannulated. Intravascular ECGs were recorded during position control, and guidewire and water column lead were compared in the same patient with regard to the quality of the ECG reading and P-wave enhancement. In another 40 patients, the guidewire was inserted only 10 cm and the central venous catheter advanced under guidewire ECG control. Correct position of all the central venous catheters was confirmed by chest radiography. RESULTS: All central venous catheters were correctly positioned in the superior vena cava. For the same catheter position, the P-wave was significantly larger in the guidewire ECG than in the fluid column system. No changes in the quality of the ECG were detected when the guidewire was advanced or withdrawn by 1 cm relative to the catheter tip. Cardiac dysrhythmias were not seen during ECG-monitored advancement of the guidewire. CONCLUSIONS: ECG quality using a guidewire lead is superior to the water column-based system. Furthermore, it is independent from the exact position of the guidewire as related to the tip of the catheter. Using intravascular guidewire ECG during advancement can prevent induction of dysrhythmias.

Adult↗
PubMed2001

Pharmacokinetics of levofloxacin during continuous veno-venous hemofiltration.

OBJECTIVE: To study the effect of continuous veno-venous hemofiltration (CVVHF) on the pharmacokinetics of levofloxacin in critically ill patients with acute renal failure. DESIGN: Open-label study. SETTING: Anesthesiology ICU, University Hospital of Regensburg. PATIENTS: Six critically ill patients treated with CVVHF because of acute renal failure needing antimicrobial therapy. INTERVENTIONS: Levofloxacin i.v. 250 mg qd with a starting dose of 500 mg. CVVHF with the following characteristics: hemofilter AN69 hollow fibers of 0.90 m2 area, blood flow 150 ml/min, ultrafiltrate flow 1.3 l/h, filtrate substitution in post-dilution mode. MEASUREMENTS AND RESULTS: The plasma pharmacokinetics and clearance of levofloxacin by hemofiltration were established on day 1 and day 4-6 of treatment. Levofloxacin was determined by high-performance liquid chromatography (HPLC). Mean (range) peak plasma concentrations after levofloxacin 500 mg single dose (s.d.) and 250 mg multiple dose (m.d.) were 6.4 (2.7-9.4) and 8.2 (4.7-10.3) mg/l, trough levels 2.7 (1.4-5.0) and 2.9 (1.7-3.9) mg/l, half-life 28 (19-38) and 22 (17-31) h, volume of distribution 1.2 (0.72-1.6) l/kg and 0.91 (0.52-2.0) l/kg, respectively. The mean sieving coefficient was 0.96 (0.79-1.09), mean total clearance 47 (20-89) ml/min, and mean clearance by hemofiltration 21 (13-27) ml/min, respectively. CONCLUSIONS: A dosage schedule of levofloxacin 250 mg qd with a 500 mg loading dose seems appropriate for anuric patients during CVVHF. Sufficiently high steady-state concentrations of levofloxacin were achieved after the first dose. Undesired accumulation of levofloxacin was not observed.

Acute Kidney Injury↗
PubMed1999

Cardiovascular autonomic dysfunction and hemodynamic response to anesthetic induction in patients with coronary artery disease and diabetes mellitus.

UNLABELLED: Autonomic neuropathy is a major complication of diabetes mellitus and is reported to be associated with increased perioperative hemodynamic instability. We investigated the relationship between autonomic dysfunction and hemodynamic response to anesthetic induction in diabetic and nondiabetic patients with coronary artery disease. We studied 60 patients scheduled for coronary artery surgery, 30 suffering from diabetes mellitus. Preoperative evaluation included traditional cardiovascular autonomic function tests (coefficient of variation of 150 beat-to-beat intervals in heart rate at rest, heart rate response to deep breathing, and heart rate and arterial blood pressure response to standing), spectral analysis of blood pressure and heart rate variability (HRV), and the computation of spontaneous baroreflex sensitivity. After premedication with clorazepate, anesthesia was induced with sufentanil (0.5 microg/kg), etomidate (0.1-0.2 mg/kg), and vecuronium (0.1 mg/kg). Heart rate and blood pressure before anesthetic induction and before and after tracheal intubation were compared between groups. Autonomic function tests, spectral analysis of HRV, and spontaneous baroreflex sensitivity revealed significant differences between patient groups. Most diabetic patients (n = 23) had one or more abnormal test results, in contrast to most nondiabetic patients, who did not show signs of autonomic neuropathy (n = 23). There was no relationship between cardiovascular autonomic function and hemodynamic behavior during anesthetic induction. The blood pressure response to anesthetic induction was not different between patient groups, even when comparing the subgroups with and without abnormal autonomic function tests. These findings indicate that increased hemodynamic instability during anesthetic induction is not obligatory in patients with diabetes mellitus and autonomic dysfunction. IMPLICATIONS: This study indicates that increased hemodynamic instability during anesthetic induction is not obligatory in patients with coronary artery disease and autonomic dysfunction.

Adult↗
PubMed1997

Heart rate variability in patients with daytime sleepiness suspected of having sleep apnoea syndrome: a receiver-operating characteristic analysis.

1. Periodic breathing is known to be associated with cyclic fluctuations in heart rate. The purpose of this study was to evaluate the capability of spectral analysis of heart rate variability to identify episodes with periodic breathing in patients suspected of having sleep apnoea syndrome. 2. Forty-eight subjects complaining of chronic day-time sleepiness were studied using polysomnography and additional monitoring of Holter-ECG and synchronized pulse oximetry. The recordings were divided into 20 min episodes which were identified as recordings registered during normal breathing, periodic breathing, and periods of both normal and abnormal breathing. Power spectral analysis was performed on episodes which met the criteria of stationary of data (313 episodes with normal breathing, 264 episodes with continuous periodic breathing, 80 episodes with both normal and periodic breathing patterns). 3. The ability of parameters, derived from analysis of heart rate variability, to discriminate between episodes with normal and periodic breathing was assessed by receiver-operating characteristic analysis. 4. The spectral power component in the frequency range 0.01-0.07 Hz revealed the greatest accuracy for discriminating between normal and periodic breathing (area under the receiver-operating characteristic curve = 0.929; standard error = 0.009). The analysis of the episodes classified as false-positive at a given test sensitivity of 90% and a corresponding specificity of 77% revealed that half of these episodes had been recorded during transient central nervous arousal reactions related to periodic leg movements or heavy snoring. 5. We concluded that power spectral analysis of heart rate variability offers a possible means of identifying episodes of sleep-related breathing disorders or periodic leg movements. Therefore, analysis of heart rate variability may be a valuable additional diagnostic tool in patients undergoing Holter-ECG recording.

Adult↗
PubMed1996

A comparison of the use of transoesophageal Doppler and thermodilution techniques for cardiac output determination.

Doppler cardiac output (CO) determination is discussed as a non-invasive alternative to CO estimation by thermodilution. This study was designed to compare the accuracy of a new transoesophageal Doppler device with the thermodilution technique. In 24 patients undergoing coronary artery bypass surgery, CO was determined simultaneously by the oesophageal Doppler (OD) and thermodilution (TD) method in triplicate for three sample episodes: after induction of anaesthesia during clinical steady-state conditions (A), after start of surgery (B), and after sternotomy (C). The agreement between ODCO and TDCO estimations was assessed by analysing the mean difference, indicating the systematic error, and analysing the distribution of differences between the two methods. The bias between ODCO and TDCO estimations was 0.38 (-0.06 to +0.81) L min-1 (mean and 95% confidence interval) for sample episode A, 0.48 (-0.11 to +1.1) L min-1 for sample episode B, and 0.69 (+0.08 to +1.3) L min-1 (P < 0.05 vs. zero) for sample episode C. Bias analysis of the log-transformed data revealed that 95% of the ODCO values differed from TDCO values by 43% below to 50% above for sample episode A, by 39% below to 95% above for sample episode B, and by 32% below to 96% above for sample episode C. Analysis of the changes in CO from sample episode A to B and from sample episode B to C, expressed as percentage values, showed a non-significant bias between the methods, but the 2 SD limits were +/-44% and +/-36% respectively. Our findings suggest that CO estimation by OD cannot replace estimation by the TD method.

Adult↗
PubMed1996

Perioperative changes in cardiac autonomic control in patients receiving either general or local anesthesia for ophthalmic surgery.

To investigate whether local (LA) or general anesthesia (GA) provides more perioperative stability in cardiac autonomic tone, we analyzed heart rate variability (HRV) by means of spectral analysis, intraoperatively and up to 3 h postoperatively, in otherwise healthy patients scheduled for cataract surgery. Fourteen patients received GA (premedication: clorazepate; anesthetic induction: propofol, alfentanil, atracurium; anesthetic maintainance: isoflurane, alfentanil; airway management: laryngeal mask airway), and 14 patients received LA (retrobulbar block with bupivacaine/mepivacaine). In the GA group, total power, as an indicator of cardiac autonomic activity, was significantly reduced intraoperatively and increased slowly during the postoperative period. The ratio of low frequency/high frequency (LF/HF) power, indicating cardiac sympathovagal balance, did not change significantly intraoperatively and remained stable in the postoperative period. The LA group showed no significant changes in total power intraoperatively. Postoperatively, heart rate and the LF/HF power ratio were significantly increased in the LA group compared to the GA group. GA as described above was associated with intra- or postoperative stability of the cardiac sympathovagal balance. Thus GA had no disadvantageous effects on the perioperative cardiac autonomic tone during ophthalmic surgical procedures compared to LA in otherwise healthy patients.

Adult↗
PubMed1996

Changes in cardiac autonomic control during nocturnal repetitive oxygen desaturation episodes in patients with coronary artery disease.

BACKGROUND: Periodic fluctuations in respiration such as Cheyne-Stokes respiration or the sleep apnoea syndrome are known to be associated with very-low-frequency oscillations in heart rate (cycle times about 30-120s), which may be related to periodic changes in sympathetic and vagal tone. Since disturbances in cardiac sympathovagal balance have been associated with increased cardiovascular morbidity and mortality, especially in patients with coronary artery disease (CAD), we investigated changes in cardiac autonomic control in patients with CAD during periodic breathing episodes. METHODS: Thirty-five patients with a left ventricular ejection fraction (LVEF) of > 50% and 13 patients with an LVEF of < or = 35%, who were scheduled for coronary bypass surgery, were studied using a nocturnal Holter electrocardiograph (ECG) and pulse oximetric recordings. Heart rate variability was assessed by spectral analysis during cyclic oxygen desaturation episodes, indicating periodic breathing patterns, and during control episodes with normal oxygen saturation. RESULTS: Cyclic oxygen desaturation episodes with a duration of at least 20 min were observed in 17 patients with an LVEF of > 50% and in nine patients with an LVEF of < or = 35% (minimal oxygen saturation 83.9 +/- 3.1 versus 80.4 +/- 5.6%; cycle frequency between 0.0068 and 0.0294 Hz, no significant differences between groups), all of which were associated with very-low-frequency (0.0033-0.04 Hz) oscillations in the heart rate. During cyclic desaturation episodes patients with normal, as well as those with imparied left ventricular function, had marked increases (P < 0.01) in very low frequency power, low frequency (0.04-0.15 Hz) power and the ratio of low-to-high frequency (0.15-0.4 Hz) power. The low:high frequency ratio was significantly higher in patients with an LVEF of > 50% than in patients with an LVEF of < or = 35% during cyclic desaturation episodes, but not during control episodes. CONCLUSIONS: Repetitive oxygen desaturation episodes are associated with marked changes in heart rate variability which indicate cardiac sympathetic predominance in patients with CAD. Our results suggest differences in the modulation of cardiac sympathovagal balance during periodic breathing episodes between patients with normal and imparied left ventricular function.

Adult↗
PubMed1994

Hypoxaemia and myocardial ischaemia on the night before coronary bypass surgery.

Using pulse oximetry and Holter ECG monitoring on the night before coronary bypass surgery, we studied 30 male patients with coronary artery disease to determine the relationship between nocturnal hypoxaemia and myocardial ischaemia. The patients received intensive anti-angina medication and were sedated with clorazepate. Ten patients developed a total of 42 ischaemic episodes, 24 of which occurred between 22:00 and 06:00. Mean heart rate was significantly higher in patients with ischaemia than in those without ischaemia. In 60% of all patients, heart rate increased > or = 20% at the onset of the ischaemic episode. The patients spent a median of 2 (range 0.02-40.6)% of the night with oxygen saturation (SpO2) < 90% (the minimum SpO2 value recorded was 84 (69-88) %). Only five ischaemic episodes were associated with respiratory events. These were not associated with either extraordinary oxygen desaturation or marked increases in heart rate. Comparing patients with and without ischaemia, there were no significant differences in the extent of nocturnal hypoxaemia or the pattern of desaturation episodes (cyclic variations in saturation characteristic of periodical breathing vs non-cyclic desaturation episodes). Despite marked nocturnal hypoxaemia, simultaneous occurrence of desaturation episodes and myocardial ischaemia was a rare event in our study.

Aged↗