Sympatric divergence and clinal variation in multiple coloration traits of Ficedula flycatchers.

Geographic variation in phenotypes plays a key role in fundamental evolutionary processes such as local adaptation, population differentiation and speciation, but the selective forces behind it are rarely known. We found support for the hypothesis that geographic variation in plumage traits of the pied flycatcher Ficedula hypoleuca is explained by character displacement with the collared flycatcher Ficedula albicollis in the contact zone. The plumage traits of the pied flycatcher differed strongly from the more conspicuous collared flycatcher in a sympatric area but increased in conspicuousness with increasing distance to there. Phenotypic differentiation (PST ) was higher than that in neutral genetic markers (FST ), and the effect of geographic distance remained when statistically controlling for neutral genetic differentiation. This suggests that a cline created by character displacement and gene flow explains phenotypic variation across the distribution of this species. The different plumage traits of the pied flycatcher are strongly to moderately correlated, indicating that they evolve non-independently from each other. The flycatchers provide an example of plumage patterns diverging in two species that differ in several aspects of appearance. The divergence in sympatry and convergence in allopatry in these birds provide a possibility to study the evolutionary mechanisms behind the highly divergent avian plumage patterns.

Candidate genes for colour and vision exhibit signals of selection across the pied flycatcher (Ficedula hypoleuca) breeding range.

The role of natural selection in shaping adaptive trait differentiation in natural populations has long been recognized. Determining its molecular basis, however, remains a challenge. Here, we search for signals of selection in candidate genes for colour and its perception in a passerine bird. Pied flycatcher plumage varies geographically in both its structural and pigment-based properties. Both characteristics appear to be shaped by selection. A single-locus outlier test revealed 2 of 14 loci to show significantly elevated signals of divergence. The first of these, the follistatin gene, is expressed in the developing feather bud and is found in pathways with genes that determine the structure of feathers and may thus be important in generating variation in structural colouration. The second is a gene potentially underlying the ability to detect this variation: SWS1 opsin. These two loci were most differentiated in two Spanish pied flycatcher populations, which are also among the populations that have the highest UV reflectance. The follistatin and SWS1 opsin genes thus provide strong candidates for future investigations on the molecular basis of adaptively significant traits and their co-evolution.

The effects of midazolam reversal by RO 15-1788 on cerebral perfusion pressure in patients with severe head injury.

In patients with severe head injury, midazolam is a convenient agent for sedation during mechanical ventilation, although its sedative effect can be prolonged. We investigated the effects of acute midazolam reversal by RO 15-1788 (RO), a benzodiazepine antagonist, on intracranial pressure (ICP), cerebral perfusion pressure (CPP) and on recovery in 18 studies performed on 15 patients with severe head injury (Glasgow coma score less than 8). ICP increased significantly from 16.3 mmHg +/- 2 (mean +/- SEM) to 24.1 mmHg +/- 4.2 (p less than 0.02) and to 25.2 mmHg +/- 4 (p less than 0.01), 5 and 10 min respectively after RO administration. Analysis of the results showed 2 patterns of response in ICP. In patients with good control of ICP before RO administration, there was no change in ICP and CPP, whereas in patients with abnormal ICP, RO injection induced severe increase in ICP and concomitant decrease in CPP. Arousal after midazolam reversal was obvious in 5 patients who were quickly extubated. Midazolam reversal by RO should not be attempted in patients with severe head injury and unstable ICP.

Human errors in a multidisciplinary intensive care unit: a 1-year prospective study.

OBJECTIVES: To determine the incidence and identify risk factors of critical incidents in an ICU. DESIGN: Prospective observational study of consecutive patients admitted over 1 year to an ICU. Critical incidents were recorded using predefined criteria. Their causes and consequences were analysed. The causes were classified as technical failure, patient's underlying disease, or human errors (subclassified as planning, execution, or surveillance). The consequences were classified as lethal, leading to sequelae, prolonging the ICU stay, minor, or without consequences. The correlation between critical incidents and specific factors including patient's diagnosis and severity score, use of monitoring and therapeutic modalities was analysed by uni- and multivariate analysis. SETTING: An 11-bed multidisciplinary ICU in a non-university teaching hospital. PATIENTS: 1,024 consecutive patients admitted to the ICU. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: The median length of ICU stay by the 1,024 patients was 1.9 days. Of the 777 critical incidents reported 2% were due to technical failure and 67 % to secondary to underlying disease. There were 241 human errors (31%) in 161 patients, evenly distributed among planning (n = 75), execution (n = 88), and surveillance (n = 78). One error was lethal, two led to sequelae, 26 % prolonged ICU stay, and 57 % were minor and 16 % without consequence. Errors with significant consequences were related mainly to planning. Human errors prolonged ICU stay by 425 patient-days, amounting to 15 % of ICU time. Readmitted patients had more frequent and more severe critical incidents than primarily admitted patients. CONCLUSIONS: Critical incidents add morbidity, workload, and financial burden. A substantial proportion of them are related to human factors with dire consequences. Efforts must focus on timely, appropriate care to avoid planning and execution mishaps at the beginning of the ICU stay; surveillance intensity must be maintained, specially after the fourth day.

General anaesthesia for supratentorial neurosurgery.

Anaesthesia for the surgical treatment of supratentorial tumours requires an understanding of: the pathophysiology of a localised or generalised increase in intracranial pressure (ICP), the regulation and maintenance of intracerebral perfusion, avoidance of secondary systemic insults to the brain, and the effects of anaesthetic drugs on ICP, cerebral perfusion and cerebral metabolism. Knowledge of the therapeutic options available for decreasing ICP, brain bulk and brain tension perioperatively is also essential. Potential complications which may present during supratentorial neurosurgery include massive intraoperative haemorrhage and seizures. The fact that the surgeon is operating on a tensed brain is also a potential source of difficulty. The need to monitor brain function and environment during surgery poses a challenge to the anaesthesiologist, as does the achievement of rapid emergence from anaesthesia with the adequate use of anaesthetic drugs.

Total intravenous anesthesia with propofol for burst suppression in cerebral aneurysm surgery: preliminary report of 42 patients.

Forty-two patients underwent cerebral aneurysm clipping at our institution in 1991, 35 with a ruptured aneurysm and 7 with an unruptured aneurysm. Preoperatively, 22 patients with a ruptured aneurysm were graded I or II according to the World Federation of Neurosurgical Societies and 21 underwent an operation on the first day. All underwent a standard cerebral protective general anesthesia, combining propofol with fentanyl, arterial normotension (mild hypertension with volume loading and/or dopamine during temporary clipping and once the aneurysm was secured), normocarbia or slight hypocarbia, brain relaxation with lumbar drainage, mannitol and propofol, and electroencephalogram burst suppression when temporary clipping (> or = 2 min) was required. Propofol doses for induction were 1.8 +/- 0.1 mg/kg (mean +/- standard error); for maintenance, doses were 86 +/- 3.5 micrograms/kg per min; and for burst suppression doses were 500 micrograms/kg per min. After clipping, the propofol dose rate was reduced to allow early recovery and neurological examination in the operating room. In 21 patients, temporary clipping was required for a mean duration of 8.8 +/- 1.3 minutes (range, 2-29); none of these patients deteriorated as compared with their preoperative neurological state. Twenty-four of the 42 patients (57%) had a Glasgow Coma Outcome Scale (GOS) score of 1, 7 patients had a GOS score of 2, 8 had a score of 3, and 3 had a score of 5. Thirty-two patients were extubated in the operating room with a mean GOS Score of 13.2 +/- 0.5, and 10 were extubated later in the intensive care unit.(ABSTRACT TRUNCATED AT 250 WORDS)

A new way to monitor external ventricular drainage.

External ventricular drainage is prone to mechanical complications and monitoring the system is not easy. It requires repeated checking of the drip or the level of the drained cerebrospinal fluid (CSF) in the bag. It was thus proposed that an efficient method by which to monitor the complete external ventricular drainage system would be by continuously weighing the drained CSF. Using weighing scales, a converter, and a recorder, the CSF weight was displayed as a function of time (i.e., flow, if the specific gravity of the CSF is 1, which is usually the case as an approximation). This system was used in 16 comatose patients (11 with subarachnoid hemorrhages and 5 with hydrocephaly during 204 recorded periods of 22.7 +/- 2.8 hours (mean +/- standard deviation). The mean flow was 0.17 +/- 0.05 ml/min. A cessation of CSF flow was seen graphically as a plateau. This occurred 18 times because of obstruction, which was relieved before clinical worsening by making minor adjustments in 15 patients and by reinsertion of a drain in 3 patients. Nociceptive stimuli like tracheal suctioning were also clearly visible on the graph (increased slope, i.e., increased CSF flow). This type of external ventricular drainage monitoring appears to be safe and reliable, giving indications before changes in medical condition. The observed flow, however, is not equal to its rate of secretion but rather to the difference between CSF secretion and reabsorption.

Changes in CSF pressure after mannitol in patients with and without elevated CSF pressure.

In view of the current concern that rapid infusion of mannitol might initially aggravate intracranial hypertension, the effects of a mannitol infusion on lumbar cerebrospinal fluid pressure (CSFP) were investigated in 49 patients. The studies were performed when the patients were under general anesthesia prior to elective craniotomy for tumor resection or intracerebral aneurysm clipping. The patients were divided into two groups: 24 patients with normal CSFP (Group I, mean CSFP 10.5 mm Hg) and 25 with raised CSFP (Group II, mean CSFP 20.8 mm Hg). Measurements of CSFP, mean arterial blood pressure (MABP), and central venous pressure (CVP) were made serially during and after the infusion of 20% mannitol (1 gm.kg-1 infused over a 10-minute interval). In both groups, mannitol infusion provoked a fall in MABP and an increase in CVP. An immediate decrease [corrected] in CSFP was observed in Group II, whereas CSFP increased transiently but significantly in Group I. Analysis of the arterial and venous driving pressures which contribute to CSFP suggests that the transient increase in CSFP after mannitol in Group I was partly due to the increase in CVP. The presence of intracranial hypertension may thus alter the CSFP response to arterial and venous pressure changes. Cerebral blood volume (CBV) was measured in dogs in a separate study analogous to the human protocol. The CBV increased approximately 25% over control values after mannitol infusion both in the normal animals and in those with CSFP raised by an epidural balloon. The response of the CSFP to mannitol infusion differed between both groups in a fashion similar to that observed in the human subjects. Thus, differences in CBV changes after mannitol do not account for the difference in CSFP response between normal subjects and those with raised CSFP.

Effects of rapid mannitol infusion on cerebral blood volume. A positron emission tomographic study in dogs and man.

Positron emission tomography was used to study the effect of a rapid infusion of mannitol on cerebral blood volume (CBV) in five dogs and in three human subjects. The ability of mannitol to reduce intracranial pressure (ICP) has always been attributed to its osmotic dehydrating effect. The effects of mannitol infusion include increased osmolality, total blood volume, central venous pressure (CVP), and cerebral blood flow, and decreased hematocrit, hemoglobin concentration, serum sodium level, and viscosity. Mannitol's ability to dilate the cerebral vasculature, either directly or indirectly, and thus to transiently increase ICP, is a subject of controversy. By in vivo labeling of red cells with carbon-11, the authors were able to demonstrate an early increase in CBV in dogs of 20%, 27%, and 23% (mean increase, p less than 0.05) at 1, 2, and 3 minutes, respectively, after an infusion of 20% mannitol (2 gm/kg over a 3-minute period). The animals' muscle blood volume increased by 27% (mean increase, p less than 0.05) 2 minutes after infusion. In the human subjects, lower doses and a longer duration of infusion (1 gm/kg over 4 minutes) resulted in an increase in CBV of 8%, 14% (p less than 0.05), and 10% at 1, 2, and 3 minutes, respectively, after infusion. In dogs, ICP increased by 4 mm Hg (mean increase, p less than 0.05) 1 minute after the infusion, before decreasing sharply. The ICP was not measured in the human subjects. Hematocrit, hemoglobin, sodium, potassium, osmolality, heart rate, mean arterial pressure (MAP), and CVP were measured serially. Results of these measurements, as well as the significant decrease in MAP that occurred after mannitol infusion, are discussed. This study demonstrated that rapid mannitol infusion increases CBV and ICP. The increase in muscle blood volume, in the presence of a decreased MAP and an adequate CVP, suggests that mannitol may have caused vasodilation in these experiments.

Ejection as a key word for the dispatch of a physician staffed helicopter: the Swiss experience.

We evaluated the type and severity of injuries and the possible influence of a helicopter staffed by a physician on the outcome of 71 consecutive occupants ejected from a four-wheel vehicle ejected occupants who were cared for by the Swiss Air Rescue Helicopter team from January 1994 to February 1999. The investigation and the data collection were planned prospectively. The following data were collected for each patient ejected from a four wheel vehicle: (1) demographic information; (2) type of injury; (3) vital signs on scene, in flight and at hospital; (4) hospital diagnosis; (5) injury severity score; (6) secondary transfer; (7) length of stay in hospital and on intensive care; and (8) outcome at hospital discharge. A control group included consecutive patients cared for by the same rescue team during the same period but who were not ejected out of their vehicle. Forty-four percent of the ejected patients had a GCS < or = 8, 21% were hypotensive and 22% had respiratory problems. Nine patients died at the scene. A total of 53% of the 62 ejected patients who were transported had an ISS > or = 16. The median ISS was 17. A total of 37% of the patients were intubated at the scene, needle chest decompression was performed in 5% and major analgesia was used in 27% of the cases. A total of 38% of the patients needed surgery in the first 4 h, 34% needed intensive care. No patient needed secondary transfer to the Trauma Centre if they were not brought there in the first instance. The outcome was poor in 27 cases (38%): 17 died and 10 needed transfer to specialised institutions. Non-ejected patients suffered mostly from head and neck injuries (50%) of which 9% were severe (head and neck AIS > or = 4, P < 0.05). Thoracic injuries were less frequent (35%) of which 13% were severe (thorax AIS > or = 4, P < 0,05). The median ISS was 9 for the non-ejected patients, P < 0.05. In conclusion, ejection from a four-wheel vehicle causes more severe injuries and requires a high number of advanced life support manoeuvres. Based on the mechanism of injury alone, patients ejected from four-wheel vehicles should automatically receive a response from the best available pre-hospital team. In our system, this means the dispatch of a physician staffed helicopter.

Impact of duration of chest tube drainage on pain after cardiac surgery.

OBJECTIVE: This study was designed to analyze the duration of chest tube drainage on pain intensity and distribution after cardiac surgery. METHODS: Two groups of 80 cardiac surgery adult patients, operated on in two different hospitals, by the same group of cardiac surgeons, and with similar postoperative strategies, were compared. However, in one hospital (long drainage group), a conservative policy was adopted with the removal the chest tubes by postoperative day (POD) 2 or 3, while in the second hospital (short drainage group), all the drains were usually removed on POD 1. RESULTS: There was a trend toward less pain in the short drainage group, with a statistically significant difference on POD 2 (P=0.047). There were less patients without pain on POD 3 in the long drainage group (P=0. 01). The areas corresponding to the tract of the pleural tube, namely the epigastric area, the left basis of the thorax, and the left shoulder were more often involved in the long drainage group. There were three pneumonias in each group and no patient required repeated drainage. CONCLUSIONS: A policy of early chest drain ablation limits pain sensation and simplifies nursing care, without increasing the need for repeated pleural puncture. Therefore, a policy of short drainage after cardiac surgery should be recommended.

Recovery from anesthesia and postoperative extubation of neurosurgical patients: a review.

The most feared complications after intracranial surgery are development of an intracranial hematoma and major cerebral edema. Both may result in cerebral hypoperfusion and brain injury. Arterial hypertension via catecholamine release or sympathetic stimulation and hypercapnia may be predisposing factors. Other systemic secondary insults to the brain such as hypoxia and hypotension may exacerbate neuronal injury in hypoperfused areas of the brain. Thus, the anesthetic emergence of a neurosurgical patient should include maintenance of stable respiratory and cardiovascular parameters. Minimal reaction to the endotracheal tube prevents sympathetic stimulation and increases in venous pressure. On one hand, a delayed emergence and later extubation in the intensive care unit (ICU) might be recommended to achieve better thermal and cardiovascular stability after major intracranial procedures. On the other hand, the timely diagnosis of neurosurgical complications is required to limit brain damage; the diagnosis of complications relies on rapid neurological examination after early awakening. After uncomplicated surgery, normothermic and normovolemic patients generally recover from anesthesia with minimal metabolic and hemodynamic changes. Thus, early recovery and extubation in the operating room is the preferred method when the preoperative state of consciousness is relatively normal and surgery does not involve critical brain areas or extensive manipulation. In the complicated or unstable patient, the risks of early extubation may outweigh the benefits. It is, however, often possible to perform a brief awakening of the patient without extubation to allow early neurological evaluation, followed by delayed emergence and extubation. Close hemodynamic and respiratory monitoring are mandatory in all cases. The availability of ultrashort intravenous anesthetic agents and adrenergic blocking agents has added to the flexibility in the immediate emergence period after intracranial surgery.

Effects of neck position and head elevation on intracranial pressure in anaesthetized neurosurgical patients: preliminary results.

This study reports the collective effect of the positions of the operating table, head, and neck on intracranial pressure (ICP) of 15 adult patients scheduled for elective intracerebral surgery. Patients were anesthetized with propofol, fentanyl, and maintained with a propofol infusion and fentanyl. Intracranial pressure was recorded following 20 minutes of stabilization after induction at different table positions (neutral, 30 degrees head up, 30 degrees head down) with the patient's neck either 1) straight in the axis of the body, 2) flexed, or 3) extended, and in the five following head positions: a) head straight, b) head angled at 45 degrees to the right, c) head angled at 45 degrees to the left, d) head rotated to the right, or e) head rotated the left. For ethical reasons, only patients with ICP < or = 20 mm Hg were included. Intracranial pressure increased every time the head was in a nonneutral position. The most important and statistically significant increases in ICP were recorded when the table was in a 30 degree Trendelenburg position with the head straight or rotated to the right or left, or every time the head was flexed and rotated to the right or left-whatever the position of the table was. These observations suggest that patients with known compromised cerebral compliance would benefit from monitoring ICP during positioning, if the use of a lumbar drainage is planed to improve venous return, cerebral blood volume, ICP, and overall operating conditions.

Effect of clonidine on ICP and on the hemodynamic responses to nociceptive stimuli in patients with brain tumors.

The effect of clonidine on intracranial pressure (ICP), mean arterial pressure (MAP), cerebral perfusion pressure (CPP), heart rate (HR), and drug requirements was studied in 24 patients scheduled for elective cerebral tumor resection (ICP < or = 20 mm Hg). The patients were randomly assigned to one of two groups: Group P (placebo), 12 patients; Group C (clonidine 3 micrograms/kg 10 min before induction), 12 patients. In all patients, anesthesia was induced with a propofol infusion (500 micrograms/kg/min) combined with fentanyl 2 micrograms/kg, lidocaine 1.5 mg/kg, and vecuronium 0.1 mg/kg. Propofol was also used for maintenance. During the preinduction period, clonidine had no effect on ICP or HR, but in clonidine-treated patients, MAP and CPP decreased significantly in comparison to those of the placebo group. During induction, ICP and HR were stable and similar in both groups. MAP and CPP remained significantly lower in Group C. At intubation and Mayfield clamp application, ICP increased in both groups, with similar values at all times. MAP increased in both groups at intubation, Mayfield clamp application, and incision, staying lower, however, in Group C. CPP followed a pattern similar to that of MAP. Propofol requirements up to the 20th min were lower in Group C than in Group P (2.08 +/- 0.83 vs. 3.3 +/- 0.7 mg/kg, p < 0.05). Finally, throughout the study, eight patients in Group C versus two in Group P had a CPP value < 60 mm Hg for > or = 1 min (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Propofol vs. thiopental-isoflurane for neurosurgical anesthesia: comparison of hemodynamics, CSF pressure, and recovery.

Sixty otherwise healthy patients with no clinical signs of intracranial hypertension who were undergoing elective intracranial surgery were randomly assigned to receive anesthesia with either thiopental, 3-6 mg/kg i.v., and isoflurane, 0.5-1.5% (group 1, N = 30) or propofol, 1-2.5 mg/kg i.v., and propofol infusion, 40-200 microg/kg/h (group 2, N = 30). Both groups received 50% nitrous oxide in O2 subsequent to dural opening. During induction, the changes in heart rate (HR), mean arterial pressure (MAP), cerebrospinal fluid pressure (CSFP), and cerebral perfusion pressure (CPP) were similar between the groups, except at 3 min when the findings (mean +/- SEM) for CPP (81 +/- 3.3 vs. 70.3 +/- 2.8 mm Hg, p <0.05) were significantly lower in group 2. At intubation, the highest level of MAP (103.1 +/- 3.3 vs. 88.9 +/- 2.7 mm Hg, p <0.05) was significantly greater in group 1. At pinhead-holder application, the highest values of HR (81.8 +/- 3 vs. 73.9 +/- 2.1 beats/min, p <0.05), MAP (112.2 +/- 3.6 vs. 98.3 +/- 3 mm Hg, p <0.05), CSFP (15.2 +/- 1.3 vs. 11.6 +/- 1.1 mm Hg, p <0.05), and CPP (97.0 +/- 3.9 vs. 86.7 +/- 3.3 mm Hg, p <0.05) were significantly greater in group 1. During early (20-30 min) recovery, group 2 had higher Glasgow Coma Scale scores and a greater percentage of patients in whom eye opening, response to commands, extubation, speech, and time/space orientation were present. In conclusion, when compared to thiopentalisoflurane for intracranial surgery, propofol produces similar HR, MAP, CSFP, and CPP responses during induction, adequate control of these responses during nociceptive stimulation, and faster recovery for cerebral function postoperatively.

Life-threatening hemorrhagic diathesis due to disseminated intravascular coagulation during elective brain tumor surgery.

Disseminated intravascular coagulation (DIC) is an extremely rare complication during elective brain tumor surgery. We report the case of a life-threatening intraoperative hemorrhagic diathesis due to a fulminating DIC during the removal of a grade III parietooccipital astrocytoma in a patient with a history of three pulmonary embolisms. Intraoperatively, the patient required 13 U of blood, 9 U of fresh-frozen plasma, and 5.45 L of colloids and crystalloids (total volume infused during the procedure: 12.5 L). Bleeding persisted for 24 h and required further blood component therapy. Laboratory data support the diagnosis of DIC: decreased fibrinogen and platelet count, prolonged thrombin and prothrombin times, and the presence of fibrin monomers. With aggressive and swift treatment of the DIC, the patient survived with transient neurological worsening.

Total intravenous anesthesia is best for neurological surgery.

We believe that today balanced TIVA represents the best anesthetic technique for neurological surgery. Freely acknowledging that this point of view is unproven (36) with regard to the hard criterion of patient outcome on leaving the hospital, we submit that the intermediate or surrogate criteria discussed make a convincing case for preferring TIVA to volatile-based anesthetic techniques. Until a study demonstrating hard outcome differences between the two techniques is achieved, we will continue to encourage the use of TIVA in neuroanesthesia, based on its practical (anesthetic depth, neuromonitoring, surgical field) and theoretical (homeostasis, metabolism, antinociception, neuroprotection) advantages.

Effect of three pretreatment techniques on hemodynamic and CSFP responses to skull-pin head-holder application during thiopentone/isoflurane or propofol anesthesia.

The effects of three different pretreatment techniques on ICP and MAP responses to pin head-holder application (HH) were studied. Thirty-two patients for elective intracranial surgery were assigned randomly to three pre-treatment groups: group I-local scalp infiltration with lidocaine (6-8 ml of 2% solution); group II-deepening of general anesthesia with either thiopentone (2 mg/kg) or propofol (0.6 mg/kg); and group III-intravenous fentanyl (4 mug/kg). Two anesthetic techniques were used, subdividing the three groups into subgroup A (thiopentone-isoflurane) and subgroup B (propofol). Measurements of MAP, cerebrospinal fluid pressure (CSFP), cerebral perfusion pressure (CPP), and heart rate (HR) were made at pretreatment, just before HH (time T0: baseline), and 0.5, 1, 2, 3, 4, and 5 min after HH. Within each group, MAP, HR, CPP, and CSFP varied similarly in both subgroups, so the data from A and B were cumulated. After HH application, MAP, HR, CPP, and CSFP increased in all groups, but significantly less in group I. The maximal MAP increase occurred at T1 and was 6.7 +/- 2.2% in group I, 27.9 +/- 4.9% in group II, and 27.1 +/- 6.5% in group III (difference between I and II-III: p <0.005). HR increased similarly in the three groups, but less in group I. The maximal CSFP increase occurred at T0.5 and was 12.2 +/- 10.0% in group I, 31.9 +/- 10.8% in group II, and 24.5 +/- 5.6% in group III (difference between I and II-III: p < -0.05). The changes in CPP paralleled MAP changes. In conclusion, the thiopentone-isoflurane sequence and continuous propofol anesthesia provide similar hemodynamic conditions and responses to nociceptive stimuli; local lidocaine infiltration achieves better control of MAP, HR, CSFP, and CPP after HH application than the deepening of general anesthesia or intravenous fentanyl.

Acute pulmonary edema in the post partum and cor triatriatum sinistrum.

A case is described of an apparently healthy young woman in her first pregnancy who presented with acute pulmonary edema in the early postpartum period in the context of mild pregnancy-induced hypertension. After quick improvement in her condition, a Doppler followed by a transesophageal study revealed a left atrial septation with a small atrial septal defect secundum type and moderate mitral regurgitation strongly suggestive of a cor triatriatum sinistrum.

Etomidate and thiopental-based anesthetic induction: comparisons between different titrated levels of electrophysiologic cortical depression and response to laryngoscopy.

STUDY OBJECTIVE: To determine whether etomidate-based induction can provide better hemodynamics than a standard thiopental sodium-based anesthetic induction. DESIGN: Prospective, single-blind clinical trial. SETTING: Multicenter university neurosurgical operating room. PATIENTS: 66 ASA physical status II and III inpatients undergoing neurosurgical procedures for intracranial tumor or other pathology. INTERVENTIONS: Patients were divided into two groups for anesthetic induction. The first group (control) was divided into two subgroups, with the first subgroup receiving "low-dose" etomidate (LET) 0.4 to 0.6 mg/kg titrated to an electroencephalographic (EEG) spectral edge frequency (SEF) of 10 to 12 Hz. The second subgroup received thiopental sodium (THIO) 3 to 6 mg/kg titrated to the same EEG endpoint. The study group was given high-dose etomidate (HET) 0.5 to 1.7 mg/kg titrated to an early burst suppression pattern. MEASUREMENTS AND MAIN RESULTS: Baseline (awake) measurements of mean arterial pressure (MAP) heart rate (HR), and SEF were obtained prior to anesthetic induction that was accomplished using a small bolus plus an infusion of the induction drug titrated to the EEG target. MAP, HR, and SEF were recorded just prior to laryngoscopy and intubation (T1), 30 seconds after laryngoscopy and intubation (T2), and 90 seconds after (T3) laryngoscopy and intubation. Times to reach EEG endpoint, along with total dose of anesthetic given, were also recorded. Compared with baseline values, the THIO group had the highest increase in both HR (22.9 +/- 4.4 bpm.) and MAP (16.8 +/- 4.2 mmHg) (P < 0.05) after laryngoscopy and intubation. The LET group also had significant increases compared with the HET group that demonstrated the least hemodynamic variability. No correlations could be made between age and dose of induction drug. CONCLUSIONS: Etomidate-based anesthetic induction, titrated to EEG burst suppression, produced stable hemodynamics during laryngoscopy and intubation as compared with lower dose, more "classic" inductions with etomidate or thiopental.