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P Krafft

Publications and source records attributed to P Krafft.

52 records · Page 3Linked to original sources
PubMed1995

Hemodynamic and analgesic effects of clonidine added repetitively to continuous epidural and spinal blocks.

Clonidine in spinal and epidural blocks prolongs anesthesia, but can cause hypotension and bradycardia. The aim of our study was to compare hemodynamic and analgesic effects of spinal versus epidural clonidine alone and after repetitive dosing. In a prospective, randomized, double-blind study, we evaluated 40 patients scheduled for lower extremity orthopedic surgery under continuous spinal or epidural anesthesia with bupivacaine 0.5% (initial dose 5 mg and 50 mg, respectively). In either spinal or epidural technique one-half of patients received clonidine (150 micrograms) in addition to bupivacaine. Repeat doses of the same anesthetic mixture were allowed in cases of subsequent pain. Mean arterial pressure (MAP) and heart rate were recorded for 6 h after each injection. Duration of clinically useful anesthesia was defined as the time from drug administration to first sensation of pain. Intrathecal, but not epidural, clonidine decreased MAP significantly compared with bupivacaine alone. MAP after intrathecal clonidine with bupivacaine was lower than epidural clonidine with bupivacaine 5 and 6 h after injection. Repetitive administration caused no further decrease in MAP. Onset time required to surgical anesthesia (sensory block of T11) did not differ among the four groups. Duration of spinal and epidural anesthesia was increased more than two fold by clonidine. In summary, the addition of clonidine prolongs analgesia by either route. These results may be explained by clonidine's sites of action in hemodynamic control and the density of bupivacaine-induced block.

Aged↗
PubMed1995

Stress response to tracheal intubation: direct laryngoscopy compared with blind oral intubation.

Haemodynamic and hormonal responses to tracheal intubation can be profound and associated with serious cardiovascular and cerebral side effects. The Augustine Guide, a device enabling blind oral intubation, has been introduced recently. The aim of our study was to compare the haemodynamic and hormonal stress response of this method with direct laryngoscopy. Thirty five patients (ASA 1 and 2) were randomly assigned to undergo either direct laryngoscopy (n = 17), or blind oral intubation (n = 18). Haemodynamic responses and concentrations of adrenaline, noradrenaline and prolactin were determined prior to induction, before intubation and 5 min after intubation. The median duration of intubation was 22s for direct laryngoscopy vs 46s for blind oral intubation (p < 0.05). Between the groups, no significant differences were observed for heart rate, systolic or mean arterial blood pressure. Serum levels of adrenaline decreased slightly after induction and remained unaltered after intubation in both groups. Noradrenaline (1.01 vs 0.66 nmol.l-1) and prolactin (5.2 vs 2.9 nmol.l-1) levels were significantly higher after direct laryngoscopy compared to blind oral intubation. Although blind oral intubation took significantly longer to perform than direct laryngoscopy, hormonal stress response was less pronounced. Blind oral intubation should therefore not be withheld from patients with impaired cardiovascular reserve.

Adolescent↗
PubMed1995

Optimal values for oxygen transport during hypothermia in sepsis and ARDS.

Mild hypothermia (33 degrees C to 35.5 degrees C) is reported to improve oxygenation and survival in patients with lung failure (1). Although hypermetabolism may account for about 50% of the ventilatory demand in ARDS patients, the concept of reducing oxygen consumption (VO2) by lowering metabolic rate, has only recently gained attention (2). Our study was aimed to test whether mild hypothermia established by continuous veno-venous haemofiltration (CVVHF), could optimize values for oxygen kinetics in ARDS patients. Overall, we recruited 27 patients with ARDS and sepsis. Prior initiation of CVVHF patients had to meet the following criteria: a) Murray score > 2.5, and hypoxaemia with PaO2/FIO2 < 200, b) hyperthermia of > 38 degrees C, c) cardiovascular instability requiring inotropic support. Evaluation of cardio-respiratory data was performed within four different phases (I = before, II + III during and IV = after CVVHF) every 6 hours. Core temperature as derived from the thermistor of pulmonary artery catheter was aimed to be between 35.0 degrees C and 36.5 degrees C. Optimal values for oxygen delivery (DO2) (> 550 mL/min/m2) and VO2 (> 160 mL/min/m2) were defined according to Shoemaker and achieved by fluid loading, transfusion and inotropic support (3). Septic shock occurred in 10 of 14 nonsurvivors (nons) and 2 of 13 survivors (surv). Mean values for DO2 and VO2 were calculated at different body temperature ranges. While at 37 degrees C DO2 was identical between surv and nons, (663 +/- 128 versus 666 +/- 127 means +/- SD) moderate hypothermia led to a small decrease of DO2 in surv and a significant decrease in nons (632 +/- 134 versus 605 +/- 128 mL/min/m2) at 35 degrees C. Concerning VO2 during hypothermia, there was a significant drop in nonsurvivors while in survivors the decrease was less pronounced. We could demonstrate a decrease in DO2 and VO2 during mild hypothermia during CVVHF. However, decreases in nonsurvivors were more pronounced than in survivors. These results suggest that the inability to achieve optimal values for DO2 and VO2 during mild hypothermia induced by CVVHF could serve as a prognostic sign for fatal outcome. Although oxygen consumption is decreased during hypothermia, hypoxaemia may result due to alterations of the oxygen transport on a cellular basis. The relationship between oxygen transport and temperature during CVVHF therefore deserves further studies.

Adolescent↗
PubMed1995

Severity and outcome of ARDS: the present place of extracorporeal lung assist (ECLA).

Within the last decade extracorporeal lung assist has been recommended for the treatment of acute respiratory distress syndrome. However, this recommendation was challenged by several recent clinical studies and reviews. The goal of our analysis was therefore to investigate data on outcome and severity of gas exchange disturbance published from patients treated with ECLA. These data were compared to a historical control group consisting of ARDS patients treated conventionally. Computerized (MEDLINE 1967-95) literature search using the keywords ARDS, ECLA, ECMO, ECCO2R and HUMAN was performed. Only clinical studies published as full papers reporting data on both, patients mortality and oxygenation index (PaO2/FiO2) were included. Overall mean mortality reported was 53 +/- 22% in 17 studies (419 patients), with no apparent trend towards a higher survival within the last decade with a mean PaO2/FIO2 (14 papers; 61 +/- 17 mmHg). However, mean mortality rates of ARDS patients requiring ECLA was 52.3% and 44.9% if patients undergoing ECMO were excluded (3 papers). Therefore the mortality of these patients with severe lung injury was in the range of patients treated conventionally. Patient outcome observed in our analysis is in accordance with the mortality rates from the European ECLA centres published recently (49% in 1993). Therefore, we conclude that the mean mortality rate of patients suffering from severe ARDS treated with ECLA is in the 50% range and does not differ significantly from those of patients treated conventionally, despite significantly poorer pulmonary function.

Analysis of Variance↗
PubMed1994

Haemodynamic evaluation during small volume resuscitation in patients with acute respiratory failure.

In addition to the invasive haemodynamic monitoring procedures, an on-line assessment of cardiac performance by means of transoesophageal echocardiography might have a certain role in small volume resuscitation of patients with acute respiratory failure or Adult Respiratory Distress Syndrome (ARDS). The goal of this investigation was therefore to determine the effects of a hypertonic hyperoncotic solution, hypertonic hydoxyethl-starch (HHES), (HHES = HES [200.000/0.6-0.66; 60 g l-1; Leopold, Graz; Austria] combined with NaCl [75 g l-1) on haemodynamics and cardiac performance using the transoesophageal echocardiography. After institutional approval we investigated 23 patients suffering from septic ARDS after trauma or major surgery during four periods of resuscitation. Phase I = control values after infusion of 20 ml kg-1 crystalloid solution, phase II = 50% hypertonic hydroxyethyl-starch solution (2 ml kg-1), phase III = at the end of HHES (4 ml kg-1), IV = 30 min after the end of HHES. Before HHES-infusion, all patients showed arterial hypotension with mean arterial pressures of 64 +/- 2 mmHg. The infusion of 2 ml kg-1 HHES resulted in a significant increase of systemic and pulmonary arterial pressures over the study period. A significant improvement in cardiac output was associated with increasing stroke volumes, oxygen delivery and oxygen consumption (see Tables 1 and 2). Small volume resuscitation also resulted in significant increases of endsystolic and endiastolic left ventricular areas and the corresponding calculated wall stress (Figs 1-3). We conclude from our preliminary data that when using HHES, only modest fluid resuscitation was sufficient to restore adequate preload and oxygen delivery in patients with sepsis-related acute respiratory failure.

Adolescent↗
PubMed1994

Excursions of the cervical spine during tracheal intubation: blind oral intubation compared with direct laryngoscopy.

The most appropriate technique for performing tracheal intubation in patients with cervical spine injury is debatable. Recently, a new device enabling blind oral intubation (Augustine Guide) with the patient's head and neck in the neutral position has been introduced. The aim of this study was to compare the extent of upper cervical spine movement during intubation with this device compared to direct laryngoscopy. Twelve patients (Mallampati I and II), without a cervical spine injury, were intubated using the Augustine Guide and afterwards by direct laryngoscopy. Both procedures were viewed radiographically. Extension in the upper cervical spine was determined at the point of the maximum excursion. By evaluating the joints occiput-C3 together as a functional unit, blind oral intubation caused 17 degrees (median) less extension compared to direct laryngoscopy (p < 0.01). The median differences observed for the individual joints were: 7 degrees in occiput-C1 (p < 0.05), 5 degrees in C1-2 (p < 0.01) and 6 degrees in C2-3 (p < 0.01) respectively. Since we assume that intubation-induced excursions of the injured spine are even higher, blind oral intubation might be a safe alternative for airway management in this special group of trauma victims.

Adult↗
PubMed1994

The relationship between oxygen delivery and uptake in the critically ill: is there a critical or optimal therapeutic value? A meta-analysis.

In order to identify a critical or an optimal therapeutic value for oxygen delivery and oxygen uptake, we analysed data from 40 publications concerning the relationship between oxygen delivery and consumption in patients with adult respiratory distress syndrome, trauma or during sepsis, and in nonseptic controls. According to the outcome, the patients were allocated to either group 1 (survivors) or group 2 (nonsurvivors). While oxygen delivery and uptake (mean, SEM) were significantly higher in patients with adult respiratory distress syndrome (636, SEM 31 ml.min-1.m-2 and 155, SEM 5 ml.min-1.m-2), trauma (782, SEM 77 ml.min-1.m-2 and 167, SEM 10 ml.min-1.m-2) and sepsis (654, SEM 28 ml.min-1.m-2 and 163, SEM 5 ml.min-1.m-2) than in nonseptic controls (452, SEM 18 ml.min-1.m-2 and 126, SEM 3 ml.min-1.m-2, p < 0.05), there were no significant differences in these parameters between survivors and nonsurvivors. Although therapeutic manoeuvres were effective in increasing both oxygen delivery and consumption, these improvements were not paralleled by an increase in survival rate. The correlation between oxygen delivery and uptake is generally a result of the use of pooled data and therefore prone to mathematical coupling. This is true particularly for patients with adult respiratory distress syndrome and sepsis. Thus, our study failed to identify either an optimal or a critical value of oxygen delivery or oxygen consumption in critically ill patients.

Bacterial Infections↗
PubMed1994

Right ventricular function and oxygen transport patterns in patients with acute respiratory distress syndrome.

We investigated the impact of right ventricular performance on oxygen kinetics in 15 consecutive patients with acute respiratory distress syndrome. Six hundred and twenty-two complete assessments of haemodynamics, right ventricular function and oxygenation were used for evaluation. Patients were grouped as survivors (n = 8) and nonsurvivors (n = 7) and studied during four phases of lung failure. Oxygen delivery and consumption were significantly higher in survivors compared to nonsurvivors despite comparable arterial oxygen saturation. Right ventricular end-diastolic volumes were similar for both groups, while end-systolic volumes were significantly higher in nonsurvivors due to depressed ejection fraction (40.5 (SD 1.2) versus 34.4 (SD 2.8)%) during all phases of lung failure. No clinically relevant differences in right ventricular function or oxygenation were observed between periods of moderate or severe pulmonary hypertension. Nonsurvivors have depressed cardiac function caused by reduced contractility and not by inadequate right ventricular end-diastolic volume (preload) or increased pulmonary artery pressure (afterload). Maintenance of oxygen delivery in ARDS is predominantly a function of cardiac performance and not of pulmonary gas exchange.

Adult↗
PubMed1994

Ultrasound-guided supraclavicular approach for regional anesthesia of the brachial plexus.

We prospectively studied 40 patients (ASA grades I-III) undergoing surgery of the forearm and hand, to investigate the use of ultrasonic cannula guidance for supraclavicular brachial plexus block and its effect on success rate and frequency of complications. Patients were randomized into Group S (supraclavicular paravascular approach; n = 20) and Group A (axillary approach; n = 20). Ultrasonographic study of the plexus sheath was done. After visualization of the anatomy, the plexus sheath was penetrated using a 24-gauge cannula. Plexus block was performed using 30 mL bupivacaine 0.5%. Onset of sensory and motor block of the radial, ulnar, and median nerves was recorded in 10-min intervals for 1 h. Satisfactory surgical anesthesia was attained in 95% of both groups. In Group A, 25% showed an incomplete sensory block of the musculocutaneous nerve, whereas all patients in Group S had a block of this nerve. Complete sensory block of the radial, median, and ulnar nerves was attained after an average of 40 min without a significant difference between the two groups. Because of the direct ultrasonic view of the cervical pleura, we had no cases of pneumothorax. An accidental puncture of subclavian or axillary vessels, as well as neurologic damage, was avoided in all cases. An ultrasonography-guided approach for supraclavicular block combines the safety of axillary block with the larger extent of block of the supraclavicular approach.

Adolescent↗
PubMed1994

A new device for blind oral intubation in routine and difficult airway management.

41 patients (ASA I-II) were intubated using a new device for blind oral intubation (Augustine Guide). A group of 33 consecutive patients (Mallampati I and II), was studied for routine intubation. Another group of eight patients (Mallampati III and IV) was selected to study the guide in difficult airway management. Intubation was successful in 31 of the 33 normal patients (two patients required a second attempt), and in seven of the eight patients in the difficult intubation group (three patients with two attempts). In the remaining three patients intubation had to be performed by direct laryngoscopy. One patient (Mallampati IV), was intubated by the Augustine guide after three unsuccessful attempts by direct laryngoscopy. The Augustine Guide proved to be helpful to intubating patients with an anterior larynx and receding mandible. However, blind oral intubation attempts required a median duration of 65 s (range 35-90 s). Patients with a low Mallampati score did not benefit from the new device.

Adolescent↗
PubMed1993

Mixed venous oxygen saturation in critically ill septic shock patients. The role of defined events.

STUDY OBJECTIVE: To investigate the frequency and extent of spontaneous changes ("events") in continuously measured mixed venous oxygen saturation (SvO2) in septic patients and to determine whether attention to individual event-frequency offers additional information for patient management. DESIGN: Nonrandomized prospective study. SETTING: General intensive care unit at a university hospital. PATIENTS: Fifteen patients suffering from septic shock and multiple organ dysfunction syndrome. MEASUREMENTS: For the continuous assessment of SvO2 a fiberoptic pulmonary artery catheter (Baxter Edwards) was inserted in all patients. A certain event was defined as a sudden change in SvO2 of > or = 5 percent lasting for > 10 min. All events were grouped as either moderate (< or = 10 percent changes in SvO2) or severe events (> 10 percent changes). Hemodynamics and inotropic support, oxygenation and ventilatory support, hemoglobin levels and body temperature were determined at the event and compared with the ultimate values registered before the event. RESULTS: We evaluated 377 events during an observation period of 1,575 h. Patients' mean SvO2 levels ranged between 72 +/- 7 and 82 +/- 4. Desaturations below 65 percent (39 out of 377 events) occurred in 11 patients. Overall, 74 percent of all events were moderate and 26 percent were severe. The incidence of events was 5.6 +/- 1.5 during 24 h in survivors (n = 10) and 6.3 +/- 1.6 during 24 h in nonsurvivors (n = 5). While in survivors only 20 percent of all events were severe events, this portion was significantly higher in nonsurvivors (34 percent; p = 0.03). In 67 percent of all events we observed changes in the registered physiologic parameters or therapeutic interventions probably causing the event. The cause of the remaining 33 percent of all events could not be elucidated. CONCLUSIONS: The SvO2 of septic shock patients is mainly normal or even supranormal. However, short-term changes in SvO2 do occur frequently in these patients. Nonsurvivors exhibit a higher frequency as well as a significantly greater severity of events, which may point toward a concealed mismatch of oxygen supply and demand. A high incidence of short-term SvO2 changes in a septic shock patient may be of diagnostic and prognostic significance. Therefore, we recommend the installation of a computerized alarm-function for the automatic detection and indication of frequent events.

Adolescent↗
PubMed1991

[Infectious complications due to central venous polymeric catheters].

Due to the multitude of invasive procedures of today's intensive care medicine, infections from central venous catheters have gained increasing attention. The incidence of bacteremias arising from such devices ranges from less than 0.1 to 0.6 cases per 100 catheter-days. Factors influencing the incidence of catheter-associated infections are related to patient characteristics as well as the purpose and material of the catheter. Silicone catheters seem to carry a lower risk of infection than common polytetrafluorethylene catheters. The most frequently isolated bacteria in catheter-associated infections are coagulase-negative and coagulase-positive staphylococci, enterococci, and pseudomonas species. Septicemias due to Candida albicans frequently complicate the course of immune-compromised patients receiving total parenteral nutrition (TPE). Catheter-associated bacteremias (CAB) can arise from the contaminated hub, from which pathogens migrate intraluminally to the blood stream. When the catheter entry site is infected, bacteria may reach the blood via the extraluminal route and cause septicemia. Endemic outbreaks of CAB often originate from contaminated infusion fluids. As the clinical presentation of "catheter infections" is often uncharacteristic and insidious, a definite diagnosis depends on bacteriological examination of the catheter. Quantitative and semiquantitative culture techniques of the catheter tip help to distinguish colonization from contamination by numbers of colony-forming units per milliliter culture medium. Preliminary results can be obtained by simple Gram or acridine-orange staining of the catheter tip. The most important prophylactic measures to prevent CAB are strictly aseptic conditions when catheters are placed and meticulous care thereafter, preferably by specially trained nurses or "TPE teams".(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial Infections↗
PubMed1990

[Is TNF-alpha "ripe" for routine diagnosis in sepsis?].

Mortality of the septic syndrome is around 40-60% and can rise to 100% if multiple organ failure (MOF) develops. It is generally assumed that the high mortality of sepsis can only be reduced by early diagnosis and prevention of subsequent MOF. The aim of our study was to investigate the validity of routine TNF-alpha determination for the diagnosis of septicemia and, in combination with clinical scoring systems [MOF score and Acute Physiological and Therapeutic Intervention Score (APATIS)], to define a "therapeutic window" during which an anti-TNF-alpha agent could be applied with the greatest chance of success. METHODS. TNF-alpha serum levels were measured and APATIS and MOF scores were calculated daily in 87 ICU patients. TNF-alpha serum levels were determined by means of an immunoradiometric assay (TNF-alpha IRMA, Medgenix, Belgium). Sepsis was diagnosed in 24 patients according to clinical criteria. To quantify the severity of sepsis, we set up the APATIS. The MOF score was used to assess the severity of MOF. Data were analyzed using the SAS software package (SAS Institute, Cary, N.C.) and are expressed as mean +/- SEM. RESULTS. The mean values of all sequential TNF-alpha determinations were significantly higher in the septic patients compared to the nonseptic patients (73.2 +/- 4.3 vs 8.5 +/- 0.4 pg/ml; P less than 0.01). Similarly, the maximum TNF-alpha values were significantly higher in the septic group (156.9 +/- 26.5 vs 20.1 +/- 1.3 pg/ml; P less than 0.01). To differentiate between sepsis and nonsepsis we set the cut-off point at a TNF-alpha serum level of 40 pg/ml and calculated a sensitivity of 70.8%, a specificity of 98%, and a diagnostic accuracy of 91.3%. None of the patients with a maximum TNF-alpha level above 250 pg/ml survived. Mortality was 80% above a maximum TNF-alpha serum concentration of 200 pg/ml, whereas only 40% of patients with a TNF-alpha maximum below 150 pg/ml died. The mean APATIS and MOF scores were significantly higher for septic than for nonseptic patients (APATIS: 20.3 +/- 0.5 vs 8.1 +/- 0.2 and MOF: 9.8 +/- 0.1 vs 4.6 +/- 0.1). To differentiate between survival and nonsurvival, we set the cut-off point at 25 for APATIS and calculated a sensitivity of 79% and a specificity of 93%. At a MOF score of 8, the sensitivity was 89% and the specificity 82%. In our series cumulative mortality at a maximum MOF of less than 8 was 4% and at MOF greater than 10, 68%. We found an interval of 2.9 +/- 0.9 days between the time TNF-alpha serum levels first exceeded 40 pg/ml and the development of severe MOF (MOF greater than 10) in 13 patients. CONCLUSION. Sequential TNF-alpha serum level determinations are useful for the diagnosis and prognosis of septicemia. We found an interval of 3 days between rising TNF-alpha serum levels and the development of severe MOF. This latency may represent the "therapeutic window" during which an anti-TNF-alpha-agent, e.g., a monoclonal anti-TNF-alpha-antibody, could be applied as a therapeutic consequence.

Humans↗
PubMedDate not supplied

Ultrasound imaging for stellate ganglion block: direct visualization of puncture site and local anesthetic spread. A pilot study.

BACKGROUND AND OBJECTIVES: Stellate ganglion block (SGB) inhibits sympathetic innervation and is a common treatment for reflex sympathetic dystrophy. During the positioning of the needle, there is a risk of injury to the adjacent structures. The aim of the study was to develop an ultrasonographic imaging technique for the performance of SGB. METHODS: Twelve patients (ASA I-II) underwent SGB first by using the blind standard technique (group A: 8 mL bupivacaine 0.25%) and a second time by using an ultrasonographic imaging technique (group B: 5 mL bupivacaine 0.25%). In group B a 10 MHz ultrasound scanning probe was used to identify the anatomic structures and to guide the needle toward the transverse process of C6. RESULTS: Stellate ganglion block was satisfactory in 11 of 12 attempts by the blind technique. Ultrasonographic guidance (group B) resulted in a complete block in all patients. Onset of block was observed within 10 minutes in only 10 of 12 group A patients, while all patients in group B exhibited an adequate block after 10 minutes. During the imaging technique, the needle was inserted to an average depth of 22 +/- 3 mm and the injection of 5 mL bupivacaine resulted in an anesthetic depot with a mean diameter of 14 +/- 3 mm. Distance from the depot to the vagal nerve was 5 +/- 3 mm and 5 +/- 4 mm to the root of C6. All patients (n = 4) with a distance of < 1 mm between anesthetic depot and the root of C6 developed paresthesia within the corresponding cutaneous segment. Blind technique resulted in hematoma formation in three study patients, with no hematoma occurring during imaging technique. CONCLUSIONS: Ultrasonographic guided SGB may improve safety and allows the visualization of the local anesthetic depot. Studying the local anesthetic spread might allow the avoidance of side effects as well as typical complications of SGB.

Adult↗