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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.

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.

This prospective randomized study was designed to investigate the hemodynamic effects and quality of continuous spinal anesthesia (CSA) after rapid injection of a low dose of 0.5% bupivacaine through a 32-gauge microcatheter. The method was compared with continuous epidural (CEA) and single-dose spinal anesthesia (SSA). Seventy-seven elderly patients (ASA II-III) ranging from 57 to 94 yr old and undergoing lower limb surgery were assigned to CSA (n = 26), CEA (n = 26), and SSA groups (n = 25). In all three groups, mean arterial pressure (MAP) and heart rate (HR) were assessed continuously for 30 min after initial injection, as well as after every reinjection of local anesthetic in the CSA and CEA groups. Bupivacaine (0.5%) was used as a local anesthetic. The initial doses were 1 mL of CSA, 10 mL of CEA, and 3 mL of SSA. The reinjection doses were 1 mL of CSA and 5 mL of CEA. In the CSA group, MAP did not decrease, whereas in the CEA group, the maximum decrease was 15% +/- 3% (mean +/- SEM) for the initial injection, 12% +/- 2% for the first repetition, and 13% +/- 2% for the second repetition. In the SSA group, the largest decrease of MAP was 19% +/- 2%. All changes of MAP in the CEA and SSA groups were significantly larger compared with CSA group (P < 0.05). A total of seven patients in these two groups needed vasopressors due to a decrease of MAP of more than 30% from baseline values. Heart rate did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

To analyze the characteristics of hemodynamic parameters and cerebral dynamics, the courses of intracranial pressure (ICP), cerebral perfusion pressure (CPP), mean arterial blood pressure (MAP) and PaCO2 were analyzed retrospectively in 29 patients with severe head injury, comparing periods before and after the ventilatory mode was changed from controlled mechanical ventilation to spontaneous breathing with continuous positive airway pressure. Measurements were done before and after changing of the ventilation. Patients were allocated either to group I (n = 22, ICP remained stable: 18 +/- 2 mm Hg in both periods of observation) or group II (n = 7, ICP increased from 25 +/- 3 mm Hg to 33 +/- 4 mm Hg, P < 0.05). While changes of MAP did not reach significant levels in either group, concomitant changes in CCP appeared in group II (67 +/- 2 mm Hg to 60 +/- 2 mm Hg). Based on the observation of relatively high incidence of ICP increases and deterioration of CPP during weaning from ventilator, it is recommended that continuous ICP monitoring should be continued.

Coeliac plexus block, an established method of treatment for pain associated with pancreatitis and cancer, was used in neurosurgical patients with gastrointestinal dysfunction. The study was performed in 16 patients whose gastric reflux volume exceeded 600 ml per day for 3 consecutive days. Patients were allocated to a block group (n = 8) or a control group (n = 8). Coeliac plexus block was accomplished with a modified Moore technique using 50 ml bupivacaine 0.25%. In the block group, gastric reflux volumes for 3 days preceding coeliac plexus block and 3 consecutive days following coeliac plexus block were analysed. In the control group, gastric reflux volumes were observed over a period of 6 days. Mean (SEM) gastric reflux volume decreased significantly following coeliac plexus block from 770 (50) ml to 60 (30) ml (p < 0.01). In the control group, gastric reflux remained unchanged over the corresponding periods (730 (60) ml c.f. 670 (50) ml). The response of gastric reflux volume to coeliac plexus block suggests that the mechanism is related to inhibition of sympathetic activity in patients whose sympathetic drive is increased due to the underlying neurological disease, and possibly due to sedation withdrawal symptoms.

To examine the effects of propofol on the function of normal, collateral-dependent, and acutely ischemic myocardium, nine mongrel dogs were chronically instrumented with hydraulic occluders and ameroid constrictors were inserted around the left coronary artery, pressure transducers in the left ventricle, and heparin-filled catheters in the descending aorta and the left atrium. Regional function of normal, collateral-dependent, and acutely ischemic myocardium was assessed by sonomicrometry. Propofol (5 mg/kg intravenously) reduced function in normal myocardium (-15% +/- 5%, 1 min and -14% +/- 5%, 3 min after injection) and in collateral-dependent myocardium (-14% +/- 5% and -13% +/- 5%) to similar degrees, whereas ischemic myocardial function deteriorated significantly more (-25% +/- 10% and -23% +/- 10%, P < 0.01). Although left ventricular end-diastolic pressure remained unchanged and left ventricular contractility was reduced (-16% +/- 4%, 1 min and -15% +/- 3%, 3 min after propofol, P < 0.01), significant increases in heart rate (35% +/- 7% and 26% +/- 7%, P < 0.01) and decreases in coronary perfusion pressure (-14% +/- 5%, P < 0.05 and -19% +/- 6%, P < 0.01) occurred, likely affecting the function of ischemic myocardium. Thus, whereas collateral-dependent myocardium tolerated these adverse hemodynamic effects, ischemic myocardium responded with impairment of regional function that was significantly more pronounced than the impairment which occurred in normal or collateral-dependent areas after a 5 mg/kg intravenous bolus of propofol.

Recent investigations revealed that sufentanil increases cerebral blood flow (CBF) and intracranial pressure (ICP) in dogs and man. The aim of our study was to evaluate the impact of sufentanil on cerebral blood flow velocity and ICP in neurosurgical patients. Eight neurosurgical ICU patients with elevated ICP (> 20 mmHg) were examined. Sufentanil was given in incremental doses of 0.5, 1.0 and 2.0 micrograms kg-1. Cerebral blood flow velocity decreased significantly from 54 +/- 4 cm s-1 to 48 +/- 3 cm s-1 with the dose of 1.0 microgram kg-1 sufentanil and 47 +/- 3 cm s-1 with 2.0 micrograms kg-1, respectively (mean +/- SEM). ICP values did not increase with any of the doses studied. Thus, changes of mean arterial pressure which fell with 1.0 microgram kg-1 and 2.0 micrograms kg-1 reflect cerebral perfusion pressure alterations. Although changes of cerebral blood flow velocity revealed changes in vascular tone, ICP remained unaltered.

The new fiberoptic Camino system has recently been introduced for clinical intracranial pressure (ICP) monitoring. We compared the subdural Camino system with the well-established epidural Gaeltec system in both in vitro and clinical conditions. In the in vitro experiments the intracranial vault was simulated by a tightly closed, fluid-filled box (0.9% sodium chloride) with the two probes inside. We simulated pulsating waveforms with a jet ventilator. No difference between the simulated curve patterns and values could be detected. In the clinical studies, both probes were implanted in 10 patients who had either head injuries, subarachnoid hemorrhage, or intracerebral hemorrhage. The in vivo comparison revealed no significant difference between the two systems in the recorded pressures in group 1 (ICP less than 20 mm Hg). The subdurally placed Camino probe showed insignificantly lower ICP values than did the extradural Gaeltec probe. Although group 2 (ICP greater than 20 mm Hg) waveforms were nearly identical, significant differences (p less than 0.01) in pressure measurements (systolic, diastolic, and mean) occurred (Camino, 18 +/- 3 mm Hg; Gaeltec, 27 +/- 3 mm Hg). Correlation coefficients for mean ICP values were 0.82 in group 1 and 0.49 in group 2. Problems with the Camino probe were usually mechanical and occurred in 2 patients. The problems were either easy to recognize or manifested as an ostensibly pathologic curve. No infection occurred with either system during or following implantation. The dissimilar characteristics of the two probes can be ascribed to their different extradural and subdural implantation sites. The Gaeltec probe was more durable over the period of implantation, which averaged 98 hours and ranged from 44 to 298 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of sufentanil on intracranial pressure, mean arterial pressure, cerebral perfusion pressure and heart rate were studied in 20 neurosurgical intensive care unit patients. Epidural intracranial pressure probes were implanted in patients who suffered head injury, intracerebral haemorrhage or underwent tumour resection. Sufentanil was given intravenously in sequential doses of 0.5, 1.0 and 2.0 micrograms/kg. Fifteen minutes elapsed after each dose. The patients were allocated to either group 1 (baseline intracranial pressure less than 20 mmHg) or group 2 (baseline intracranial pressure greater than 20 mmHg). Intracranial pressure did not change significantly in either group. Therefore the falls in mean arterial pressure with the highest dose in both groups and with 1.0 micrograms/kg in group 2, closely reflect corresponding reductions in cerebral perfusion pressure. As sufentanil in itself exerts no effects on intracranial pressure, concomitant haemodynamic changes are the critical factor for an adequate cerebral perfusion pressure.

The purpose of this prospective study was to verify the value of the supine chest radiograph with regard to the recognition and quantification of pleural effusions. The findings of supine chest radiographs were compared to those of chest sonography in a total of 320 pleural cavities. The correct identification and quantification of a pleural effusion was possible by supine chest radiograph alone in only 55% of cases (176/320). In 20% (64/320) supine chest x-ray was falsely negative and in 15% (48/320) falsely positive. In 10% an existing effusion was in fact recognised on supine chest x-ray; however the amount of effusion was wrongly estimated.

Coordination of respiratory care with protection of the brain is critical in neurosurgical intensive care. Therefore, in addition to hyperventilation, adequate sedation and muscle relaxation are applied to mitigate the difficulties with control of intracranial pressure (ICP) during routine tracheobronchial suctioning (TBS). Although hypnotics have been shown to be effective in mitigating increases in ICP in response to endotracheal suctioning in paralyzed patients, brisk bucking and coughing with further increases in ICP may occur without muscle relaxation. Long-term neuromuscular (nm) paralysis may be undesirable in neurosurgical critical care because clinical evaluation with early detection of neurological deterioration will be impossible in the paralyzed patient. Therefore, the effects of TBS without and after nm blockade with an intermediate-acting nondepolarizing muscle relaxant on ICP were studied. PATIENTS AND METHODS. Nine patients with moderate increases in mean ICP of 19.2 +/- 8 mmHg due to head injuries and spontaneous subarachnoid hemorrhage were investigated. All patients were on-line sedated with midazolam and sufentanil and controlled ventilation was adjusted to maintain a paCO2 of 30 +/- 2 mmHg. Respiratory and hemodynamic parameters and ICP (epidural probe) were continuously monitored and recorded on an integrated data bank. After a bolus dose of propofol, routine TBS was performed without the use of muscle relaxants. Before the next TBS, nm monitoring was initiated and train-of-four (TOF) stimulation was imposed at the ulnar nerve using supramaximal pulses. The response of the adductor pollicis muscle was recorded by accelerometry. After supramaximal stimulation had been achieved, a bolus dose of 2 times the ED95 of vecuronium (0.12 mg/kg) was given. Depth of nm blockade was quantified by the posttetanic count (PTC). ICP and CPP were measured before, during, and after TBS. Diaphragmatic movement, bucking, and coughing were registered by visual observation and graded as absent, slight, moderate, or severe. STATISTICS. Student's t-test and the Wilcoxon test for paired data (P less than 0.05; values as mean +/- SD) were used. RESULTS. (see Table and Figure). Despite adequate sedation, moderate to severe diaphragmatic movements in response to carinal stimulation with significant increases in ICP (18.2 +/-7 to 24 +/- 8 mmHg) an d subsequent decreases in cerebral perfusion pressure (CPP) (68.9 +/- 2 to 62.4 +/- 8 mmHg) could be observed without muscle relaxation. After a bolus of vecuronium, profound nm paralysis quantified by a PTC of 5 was observed after an onset time of 4.2 +/- 1 min. ICP (20.2 +/- 8 vs. 20.1 +/- 8 mmHg) and CPP (64.0 +/- 13 vs. 64.8 +/- 13 mmHg) remained unchanged. Slight diaphragmatic movements could be elicited in only two patients during TBS. DISCUSSION. TBS is a potent trigger of diaphragmatic movement, bucking, and coughing by reflex activation of the phrenic nerve. A major determinant of the magnitude of ICP increase during TBS is the transmission of the cough-induced increase in intrathoracic pressure to the cerebral venous system. Vecuronium was utilized for nm blockade because of its proven lack of cerebral and cardiovascular side effects, its relatively short onset, and its intermediate duration of action. Despite the postulated faster onset of nm blockade in the diaphragm, suppression of thumb-twitch response to TOF stimulation does not necessarily predict absence of diaphragmatic movement elicited by excessive tracheal stimulation. As demonstrated, intense nm blockade quantified by a PTC of 5 is necessary to rule out any bucking and coughing, i.e., to ensure total diaphragmatic paralysis in response to tracheal stimulation. On-line neurological evaluation, one of the essentials in the approach to the neurosurgical patient, will not be prevented by the intermittent bolus regime utilized in this study.

Previous investigations have revealed that propofol has a beneficial effect on intracranial dynamics in patients undergoing elective neurosurgery. In the present study we evaluated the impact of propofol in patients with normal or compromised intracranial compliance. METHODS. Epidural ICP probes were implanted in 14 patients with head injury. The heart rate, mean arterial pressure (MAP), intracranial pressure (ICP) and end-tidal CO2 were recorded continuously, and propofol was given in doses of 0.5, 1.0 and 2.0 mg/kg; there were 15 min between each application. The data were evaluated 1, 2, 5 and 10 min after each application. The patients were allocated to group I (ICP less than 20 mmHg) or group II (ICP greater than 20 mmHg) according to their ICP baseline level. A statistical analysis was performed by one-way ANOVA. A P value of less than 0.05 was regarded as significant. RESULTS. In group I decreases in MAP at all measuring points were detected with 1.0 and 2.0 mg/kg propofol; ICP with 1.0 and 2.0 mg/kg and CPP with 2.0 mg/kg fell significantly. In group II MAP decreased with all doses studied, as did ICP with 1.0 and 2.0 mg/kg; however, CPP was not particularly influenced. CONCLUSION. Propofol decreased ICP in patients with normal and compromised intracranial compliance, particularly with 2.0 mg/kg. As the responses to the hypotensive effects of propofol were mild and almost similar in both groups, no inadvertent CPP drops were observed with any of the doses studied. Thus, propofol as a bolus can be used safely for the sedation of ICU patients with head injury and normal or compromised intracranial compliance.

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.

The effect of sufentanil on human cerebral blood flow (CBF) was studied in seven unpremedicated, healthy volunteers 31 +/- 3.5 yr of age (mean +/- SD) and either sex. CBF (ml.100 g-1.min-1) was measured noninvasively with the 133Xe clearance technique and a scintillation camera before and after sufentanil 0.5 micrograms/kg administered intravenously. This technique provides values for global blood flow and for gray and white matter blood flow, and from 13 preselected regions in one hemisphere. After the administration of sufentanil, the volunteers were stimulated verbally in order to prevent their loss of consciousness and hypercarbia. Heart rate (HR), arterial pressure, oxyhemoglobin saturation, and end-tidal CO2 (ETCO2 were recorded during the measurements. Neither global CBF (46.1 +/- 1.6 control and 43 +/- 1.9 after sufentanil, mean +/- SEM) nor gray (76.5 +/- 3.2 and 70.9 +/- 6.1) or white (22.7 +/- 1.5 and 24.2 +/- 1.6) matter blood flow changed significantly after sufentanil administration. As well, no significant differences in HR (72 +/- 4 control and 79 +/- 4 beats per min after sufentanil) and ETCO2 (39.8 +/- 1.4 and 41.1 +/- 1.1 mmHg) were observed. It is concluded that sufentanil has no significant effect on CBF in healthy human volunteers.