Myocardial uptake and release of lactate after high dose neurolept endotracheal intubation in coronary surgery

To evaluate the relationship between the hemodynamic and ECG variables used in routine surveillance of coronary surgery and myocardial lactate metabolism, 23 middle-aged, male, beta 1-blocked patients about to undergo coronary surgery were monitored before and after endotracheal intubation with high dose (30 micrograms/kg) fentanyl-midazolam anesthesia. The induction of anesthesia was followed by a mean arterial pressure decrease (from 98 +/- 4 to 76 +/- 3 mm Hg) and heart rate increase (from 53 +/- 3 to 66 +/- 2 beats/min). After intubation the hemodynamic variables were stable except for a further, transient increase in heart rate (to 69 +/- 2 beats/min). The myocardial uptake of lactate decreased after intubation, from 48 +/- 5 mumol/min to a lowest level of 24 +/- 3 mumol/min. A lactate release was exhibited in 7/23 patients (30%). No ST-segment changes were observed. The correlation between the myocardial lactate uptake/release and hemodynamic or ECG variables was unimpressive or non-existent (r < or = 0.20). Thus, a reduced uptake and even a release of lactate occurred irrespective of the ST-segment, heart rate, or systemic or pulmonary artery pressures. In conclusion, endotracheal intubation in patients with coronary disease was consistently (17/23 patients) followed by a reduced myocardial uptake of lactate, in spite of high dose neurolept anesthesia and beta 1-blockade. This metabolic event was not consistently related to hemodynamic changes.     

A case of type A dissecting aneurysm who are complicated by paraplegia at the 4th day after emergent operation

The 62-year-old man was admitted to our hospital with chief complaints of chest and back pain. He was diagnosed type A acute dissecting aneurysm by chest computed tomography, and underwent urgent operation, replacement of the ascending aorta and resuspension of the aortic valve. He was recovered without any neurologic complications. However, he was complicated by paraplegia at the 4th postoperative day. We suspect that is due to early thrombotic occlusion of the false lumen where the anterior spinal arteries branch by the operation.     

Collapse of the nasal endotracheal tube in the nasal cavity

A 27-year-old female with maxillary maldevelopment was admitted for mandibular sagittal splitting osteotomy with mandibular progeny. General anesthesia was induced with 100 mg of propofol and 8 mg of vecuronium. When a soft and preformed 7.0 mm North-Polar-nasotracheal tube (Portex) was inserted into the nasopharynx through the left nasal cavity, it was very difficult to advance beyond the choana. After nasotracheal intubation, the buking became harder than before when she had been ventilated with a face mask. The peak airway pressure had reached higher than 50 cmH2O with ventilation of 500 ml tidal volume. Bronchoscopy revealed that the fiberscope (3.5 mm O.D.) could not go through the choanal stenosis, because it was too narrow. Therefore, she had to be intubated by a spiral tube, 6.0 mm I.D., through the other nasal cavity with assistance of bronchoscopy, instead of the North-Polar-tube. So, we have to pay attention to the possibility of compression and collapse of a soft nasotracheal tube in the nose of the patient with choanal stenosis due to maxillary maldevelopment.     

Noninvasive estimate of work of breathing due to the endotracheal tube

BACKGROUND: Although evidence suggests that secretions lining the inner wall of the endotracheal tube (ETT) often reduce its cross-sectional area, no data are available on the work of breathing as affected by the ETT. A noninvasive method is proposed for estimating the additional work of breathing necessitated by the ETT in patients whose lungs are mechanically ventilated. This method (the acoustic-Blasius method) involves (1) determining the inner geometry of the ETT using the acoustic reflection method and (2) using these geometric data to solve the Blasius equation that characterizes the ETT pressure drop-flow relation. METHODS: To evaluate the acoustic-Blasius method in vivo, the authors computed the work of breathing due to the ETT in four healthy persons breathing through an ETT connected to a pressure-support device and in five tracheally intubated patients receiving mechanical assistance in the pressure-support mode. For the tracheally intubated patients, the reference value was the work calculated from the ETT pressure drop measured between the two ends of the ETT using a pressure catheter. RESULTS: In the healthy participants and the tracheally intubated patients, there was close agreement between inspiratory work per cycle values estimated by directly measuring the ETT pressure drop and calculated using the acoustic-Blasius method: The difference was consistently less than 0.08 joules (< 10% of the reference value). CONCLUSIONS: The data show that the acoustic-Blasius method allows noninvasive quantification of the ETT-related work of breathing in situ.     

Use of the Univent System tube for difficult intubation and for achieving one-lung anaesthesia

BACKGROUND: One-lung ventilation in major thoracic surgery is the most commonly accepted technique, not only for surgery on the lung but also in procedures involving the oesophagus, mediastinum and thoracic aorta. Conventional double-lumen tubes may sometimes be difficult to place correctly in patients in whom intubation is difficult. In such cases, the Univent System tube may be of help. It has a curved movable blocker of small calibre, and is designed to slide inside the bronchial tree and occlude all or part of the target lung. CASE REPORT: We describe a new application of the Univent System tube in three cases where intubation was presumed to be difficult, and in another with unexpected difficult intubation. The laryngeal approach was carried out with the distally displaced blocker, inserting it through the sub-epiglottis or the posterior commissure visible orifice. The tube was firmly held and slid through the length of the blocker, rotating slowly until fully introduced. The advantages and criteria for its use are discussed. CONCLUSION: Although the double-lumen tube is the first choice for one-lung ventilation, the Univent tube is a good option for selective bronchial intubation and in patients in whom difficult intubation is predicted.     

Glottic positioning of the endotracheal tube tip: a diagnostic dilemma

Distal placement of the endotracheal tube tip in the glottic opening is rarely discussed in most emergency medicine, surgery, and prehospital medicine texts. We report three cases of glottic intubation recognized after the patients were thought to have been successfully intubated. Glottic positioning of the endotracheal tube tip went unrecognized initially because of the absence of air heard over the epigastrium, the presence of bilateral breath sounds, and acceptable readings by both pulse oximetry and capnography. Recognition of this complication is aided by the use of radiographic findings, inappropriate endotracheal tube depth, and the presence of inadequate ventilatory volumes. Potential complications of glottic intubation include dislodgement of the endotracheal tube, kinking of the tube, and inadequate protection of the airway.     

Women with insulin-dependent diabetes mellitus (IDDM) complicated by eating disorders are at risk for exacerbated alterations in lipid metabolism

OBJECTIVE: To examine lipid parameters that are affected in women with insulin-dependent diabetes mellitus (IDDM) who engaged in disordered eating behaviours. DESIGN: Randomized, unmatched. SETTING: Tertiary care. SUBJECTS: Ninety women (18-46 y) with IDDM. INTERVENTIONS: Classification of subjects based on severity of eating disorder: clinical (n = 14), subclinical (n = 13) and control (n = 63). Blood was analysed for glycosylated haemoglobin (HbA1c) and serum for triglycerides and cholesterol. Carotenoid and tocopherol concentrations were analysed by high performance liquid chromatography (HPLC). Dietary intake was assessed by the National Cancer Institute food frequency questionnaire. RESULTS: HbA1c was significantly increased im women demonstrating clinical and subclinical symptoms compared to control (10.4 +/- 2.6, 10.0 +/- 1.5 and 8.3 +/- 1.6%, respectively, P < 0.05). Triglycerides concentrations were significantly increased in women with subclinical eating disorders compared to controls. In women who intentionally omitted or reduced insulin, triglyceride cholesterol and HbA1c were significantly increased compared to controls. Women with IDDM and eating disorders who exhibited bulimic behaviours consumed significantly more energy, total fat and cholesterol compared to controls and women with eating disorders who were restrained eaters. CONCLUSION: While IDDM is known to perturb lipid metabolism, these data demonstrate that eating disorders, in combination with IDDM, results in additional alterations in lipid metabolism.     

The intubation difficulty scale (IDS): proposal and evaluation of a new score characterizing the complexity of endotracheal intubation

BACKGROUND: A quantitative scale of intubation difficulty would be useful for objectively comparing the complexity of endotracheal intubations. The authors have developed a quantitative score that can be used to evaluate intubating conditions and techniques with the aim of determining the relative values of predictive factors of intubation difficulty and of the techniques used to decrease such difficulties. METHODS: An Intubation Difficulty Scale (IDS) was developed, based on parameters known to be associated with difficult intubation. It was then evaluated prospectively in a group of 311 consecutive prehospital intubations and 315 intubations in an operating room. In the operating room, the IDS was compared with two other parameters: the time to completion of intubation and the visual analog scale (VAS). Time was measured by an independent observer. Operators in both groups completed a checklist regarding the conditions of intubation. RESULTS: There is a good correlation between the IDS scale and the VAS assessment of difficulty and time to completion of intubation. VAS and time to completion have a significant but lesser correlation to each other. Comparison of IDS with operator-assessed subjective categorical impression of difficulty by Kruskall-Wallis was statistically significant. CONCLUSIONS: The IDS correlates with but is less subjective than the VAS and categorical classification. IDS correlates with time to intubation, but it offers details regarding the difficulty encountered that time alone does not. This score may not only aid in evaluation of factors linked to difficult intubations, but it may provide a uniform approach to comparing studies related to this subject.     

Detection of endotracheal tube obstruction by analysis of the expiratory flow signal

OBJECTIVE: Acute obstruction of endotracheal tubes (ETT) increases airway pressure, decreases tidal volume, increases the risk of dynamic hyperinflation by prolonging the duration of passive expiration, and prevents reliable calculation of tracheal pressure. We propose a computer-assisted method for detecting ETT obstruction during controlled mechanical ventilation. The method only requires measurement of the expiratory flow. DESIGN: Computer simulation; prospective study in two cases; retrospective study in one case and in seven patients with the adult respiratory distress syndrome (ARDS). SETTING: Laboratory of the Section of Experimental Anaesthesiology (University of Freiburg); surgical adult intensive care units in a university hospital (University of Basel) and in a university affiliated hospital (Zentralklinikum Augsburg). PATIENTS: 3 patients with partial ETT or bronchial obstructions and 7 ARDS patients. MEASUREMENTS AND RESULTS: Expiratory flow was measured using a pneumotachograph and integrated to obtain expiratory volume. The time-constant of passive expiration (tauE) as a function of expired volume [tauE(V(E)) function] was calculated from the expiratory volume/flow curve. We investigated the tauE(V(E)) function of data obtained from: (1) computer simulation of mechanically ventilated homogeneous and inhomogeneous lungs intubated with ETTs of different sizes; (2) one patient with an artificial ETT obstruction of 7.5 and 25% of the cross-sectional area of the ETT (case 1); (3) one patient with ETT obstruction due to secretions (case 2); (4) one patient with acute bronchial constriction (case 3); (5) seven ARDS patients who showed an increase in airway resistance of more than 2 cm H2O x s/l. It was found that an ETT obstruction caused an increase in tauE in early expiration (at high flow), whereas tauE in late expiration was virtually unchanged. The reason for this is the flow dependency of the increase in ETT resistance produced by ETT obstruction. Unlike ETT obstruction, an increase in pure airway resistance produced an increase in tauE throughout expiration. CONCLUSIONS: An ETT obstruction can be reliably distinguished from an increase in pure airway resistance by a characteristic pattern change in the tauE(V(E)) function, which can be detected easily even by an automated pattern recognition system.     

Hemodynamic characteristics of young men at risk for hypertension at rest and during laboratory stressors.

Examined hemodynamic activity at rest and during arithmetic and cold pressor in 105 male medical students varying in risk for hypertension. Classification into low-, moderate-, and high-risk groups was based on resting systolic blood pressure (SBP) and parental history of essential hypertension (PH). Dependent variables were SBP, diastolic BP (DBP), heart rate, and rate-pressure product (RPP). Progressively greater hemodynamic activity was seen across risk groups at rest and during the tasks. Risk groups differed significantly in SBP, DBP, and RPP at baseline and in size of response to mental arithmetic but not cold pressor. These relationships were either absent or weaker when using either risk factor alone to form risk groups. Hemodynamic reactivity to mental stress appears to be predicted better by a combination of resting SBP and hypertension than by either risk factor alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intraoperative exchange of the endotracheal tube using the Cook C-CAE airway exchange catheter

The Cook airway exchange catheter is mainly used in ICU patients to exchange endotracheal tubes. We report three cases where this device was used during anaesthesia in patients with damaged tubes in critical circumstances (oropharyngeal bleeding, head and neck surgery). It allowed a fast and atraumatic exchange of the tubes.     

The feasibility of epidural anesthesia without endotracheal intubation for abdominal surgery in patients with collagen diseases

BACKGROUND/AIMS: Patients with collagen diseases are generally regarded as high-risk surgical candidates. MATERIAL AND METHODS: To evaluate the feasibility of epidural anesthesia and to determine the risk factors in abdominal surgery for patients with collagen diseases, 20 patients with collagen diseases who underwent elective abdominal surgery were examined for their surgical outcomes and clinical characteristics. Among the 20 cases, 12 received epidural anesthesia alone without endotracheal intubation, 3 received general anesthesia only, 4 received general anesthesia with epidural anesthesia and one received lumbar anesthesia. RESULTS: Only one patient receiving epidural anesthesia died after operation. The mortality in patients receiving epidural anesthesia was 8.3% (1/12) while the overall mortality was 5.0% (1/20). No significant difference was observed either in the mortality or incidence of postoperative complications among the 4 groups according to the method of anesthesia. Patients with a dysfunction of the vital organs more often had postoperative complications than those without a dysfunction of the vital organs (p = 0.043). CONCLUSIONS: Although only a small number of patients were included in this study, these results suggested that 1) elective abdominal surgery can be as safely performed under epidural anesthesia alone as with general anesthesia even for patients with collagen diseases, and 2) the patients with collagen diseases, who preoperatively showed a dysfunction of the vital organs, might be at a higher risk for abdominal surgery.     

Skeletal muscle of a growing organism has a greater transformation after electrical stimulation than adult skeletal muscle

Six adult sheep and four newborn lambs (5 days old) were implanted with stimulator leads into the latissimus dorsi muscle and connected to a Myostim 7220 pacing system (Telectronics Pacing Systems, Inc., Englewood, CO). Electrical stimulation was started immediately after the operation. After 8 weeks of electrical stimulation, contractile force (CF) in adult sheep decreased to 76-81%, and to 78-82% in lambs. After 2 weeks' delay, CF in adults was 96-98%, and only 89-93% in lambs. After a 30 min intensive stress test, unconditioned control muscle lost 39% in lambs and 43% in adults. Muscle conditioned for 8 weeks lost 7-8% CF. However, after 2 weeks' delay, CF in adult muscle lost 33%, but only 12% in lambs. After cessation of electrical stimulation, the LDH-5 and LDH-1 + 2 fractions reverted to initial levels in adults, whereas in lambs, these levels continued to follow trends established during electrical stimulation. In both adults and lambs, the percent area occupied by the mitochondria increased during electrical stimulation by 6.9% in adults and 6.5% in lambs. After electrical stimulation cessation, the percent area in adults returned to baseline levels, whereas it continued to be elevated in lambs (3.3% vs 5.1%, respectively). The transformed muscle of the lamb did not revert to baseline levels after a delay period.     

Blood supply of the greater trochanter after trochanterotomy

The human vascular anatomy to the greater trochanter after a trochanterotomy (digastric, standard) was examined using injection techniques. Three major sources of blood supply to the greater trochanter were found: the proximal soft tissues, including the gluteus medius and minimus vascularized mainly from the internal iliac artery system; the distal soft tissues, including the vastus lateralis, vascularized from the descending branches of the lateral circumflex femoral artery; and a third possible source of blood circulation came from the transverse branch of the lateral circumflex femoral artery. Many vascular structures from the lateral circumflex femoral artery were concentrated in the anterior half of the vastus lateralis muscle. Perfusion with a latex oxide mixture and angiography after trochanterotomy proves that by using a digastric trochanterotomy, the transverse and descending branches of the lateral circumflex femoral artery to the greater trochanter thus can be preserved. With a standard trochanterotomy, the supply from the transverse and descending branches of the lateral circumflex artery are lost. These results therefore suggest that a digastric trochanterotomy is superior to a standard trochanterotomy because the blood supply of the trochanter is preserved.     

Differential sensitivity to alcohol reinforcement in groups of men at risk for distinct alcoholism subtypes

The present study examines the relationship of familial and personality risk factors for alcoholism to individual differences in sensitivity to the positively and negatively reinforcing properties of alcohol. Sixteen sons of male alcoholics with multigenerational family histories of alcoholism (MFH) and 11 men who self-report heightened sensitivity to anxiety (HAS) were compared with 13 age-matched family history negative, low anxiety sensitive men (FH-LAS) on sober and alcohol-intoxicated response patterns. We were interested in the effects of alcohol on specific psychophysiological indices of "stimulus reactivity," anxiety, and incentive reward. Alcohol significantly dampened heart rate reactivity to aversive stimulation for the MFH and HAS men equally, yet did not for the FH-LAS group. HAS men evidenced idiosyncrasies with respect to alcohol-induced changes in electrodermal reactivity to aversive stimulation (an index of anxiety/fear-dampening), and MFH men demonstrated elevated alcohol-intoxicated resting heart rates (an index of psychostimulation) relative to the FH-LAS men. The results are interpreted as reflecting a sensitivity to the "stimulus reactivity-dampening" effects of alcohol in both high-risk groups, yet population-specific sensitivities to the fear-dampening and psychostimulant properties of alcohol in the HAS and MFH groups, respectively.     

Patients with ultrasonic coarse-nodular cirrhosis who are anti-hepatitis C virus-positive are at high risk for hepatocellular carcinoma

BACKGROUND: The relationship between echosonographic patterns of patients with cirrhosis who are antihepatitis C virus (HCV)-positive, the DNA synthesis of hepatocytes, and the risk for HCC were studied. METHODS: Thirty-eight patients with anti-C-100 antibody-positive and Child's grade A posthepatitic cirrhosis were studied. DNA synthesis activity was measured by a bromodeoxyuridine (BrdU, a thymidine analogue)-labeling index (LI), using the BrdU-anti-BrdU in vitro method, and the patients were followed prospectively by frequent liver ultrasonography for 3 years. The ultrasound patterns were classified into fine, coarse, and coarse-nodular (CN) patterns, and the reproducibility of the classification in practical use also was confirmed. RESULTS: Of the 21 patients with high DNA synthesizing cirrhosis (BrdU LI > or = 1.5%), 10 (48%) showed coarse-nodular, 5 (24%) coarse, and 6 (29%) fine pattern in ultrasonography. Conversely, of the 17 patients with low DNA synthesizing LC (BrdU LI < 1.5%), only 1 (6%) showed coarse-nodular, 2 (12%) coarse, and 14 (82%) fine pattern. A significant relationship was found between the two groups of BrdU LI and ultrasound imaging patterns (P < 0.05). The incidence of CN pattern was significantly higher (P < 0.01) in the high DNA synthesizing group than in low DNA synthesizing group. Of the 11 patients with CN pattern by ultrasound imaging, 10 (91%) were in the high DNA synthesizing group, and 9 (82%) developed HCC during the follow-up period, compared with 3 of 7 (43%) with coarse, and only one of 20 (5%) with fine pattern developed HCC. The incidence of HCC was significantly higher (P < 0.01) in patients with a CN cirrhosis pattern than in those with a fine pattern. CONCLUSIONS: In patients with cirrhosis who are anti-HCV-positive, the CN pattern by ultrasound imaging indicates increased DNA synthesis of hepatocytes and a high risk for developing HCC.