Inhibition of Ironic Errors and Facilitation of Overcompensation Errors Under Pressure: An Investigation Including Perceived Weakness.

The conflicting predictions of ironic process theory and the implicit overcompensation hypothesis have been presented as a framework to explain the characteristics of errors that occur when a certain behavior is prohibited. The former predicts that instructions prohibiting a particular behavior will increase the likelihood of an outcome that should be avoided (ironic error), whereas the latter predicts that the likelihood of an outcome opposite of that to be avoided (overcompensation error) will increase. We examined how these errors, which negatively affect performance, are influenced by pressure and perceived weakness. Participants performed a tennis-stroke task, aiming to hit a ball toward a target zone while avoiding a discouraged zone. The results indicate that pressure decreases the ironic errors but increases the overcompensation errors that occur when a particular behavior is discouraged, while an increase in perceived weakness induces random errors.

Fast-track postoperative care for neonatal cardiac surgery: a single-institute experience.

PURPOSE: Perioperative fast-track management has gained wide acceptance in the field of neonatal corrective heart surgery. We have examined its impact on morbidity outcomes. METHODS: Between 1997 and 2009, 52 consecutive neonates underwent corrective repair of congenital heart defects on cardiopulmonary bypass. Fast-track management was introduced in 2006 with the aim of simplifying care; it includes early postoperative extubation with low-dose fentanyl and an pulse oximeter oxygen saturation (SpO(2)) target of ≤ 95%, early removal of indwelling lines, and early introduction of early enteral feeding. This was a retrospective review of the medical records in which perioperative characteristics and outcomes of patients operated on prior to the introduction of fast-track management care (controls, group C) were compared with those operated on following its introduction (fast-track group, group F). RESULTS: Intraoperative fentanyl was administered in significantly lower doses in group F (29.5 ± 11.5 µg/kg) than in group C (65.6 ± 34.0 µg/kg) (p < 0.001). The median number of days of postoperative mechanical ventilation and inotrope administration was significantly lower in group F (2 and 4 days, respectively) than in group C (9 and 9 days, respectively) (p < 0.001 and p = 0.003). More patients (p < 0.001) in group F (56.3%) than in group C (0%) was extubated within <24 h. The median number of days to postoperative weight recovery was significantly lower in group F (16 days) than in group C (29 days) (p = 0.003). Finally, the median number of days in the Intensive Care Unit was significantly lower (p = 0.01) in group F than in group C (16 vs. 26 days, respectively). Mortality in group F was 0% versus 17% in group C (p = 0.21). CONCLUSIONS: Fast-track management with simple care for neonates undergoing complete biventricular repair of congenital heart defects was associated with better postoperative recovery.

A portable blood analyzer that uses on-line data management to deliver higher-quality patient information.

We constructed an on-line data management system and linked it to the communication protocol of a portable blood analyzer (i-STAT) in each operating room of our institution. We developed a new program that integrates circulatory dynamics data from a monitor with laboratory data from the i-STAT. Our new program permits the results to be viewed through an intranet using a novel prototype communication device for the i-STAT 300F. We verified that this system can improve the quality of patient care both bedside and in the monitoring room and compared the costs of blood testing using a conventional desktop blood-gas analyzer and using the i-STAT. We found that the novel integration of circulatory dynamics with laboratory data enhanced the quality of intraoperative patient monitoring and reduced the cost and work load of doctors working in the operating room.

Five-day pain management regimen using patient-controlled analgesia facilitates early ambulation after cardiac surgery.

PURPOSE: Excessive pain may interrupt early rehabilitation after cardiac surgery. The purpose of this study was to evaluate the efficacy of a longer patient-controlled analgesia (PCA) regimen for early ambulation after cardiac surgery. METHODS: This study was designed to be a retrospective, single-institutional (focusing on an urban, university-affiliated hospital), pre-post intervention survey. Fifty-nine patients undergoing elective cardiac surgery were included. A long pain management regimen (subcutaneous fentanyl PCA for up to 120 h) protocol was implemented for the postoperative care for adult cardiac surgery patients. Before implementing this extended protocol, the same PCA regimen was used for up to 40 h. Perioperative and postoperative management was similar for all patients. The number of days required to walk more than 100 m without assistance was recorded. Additional usage of analgesic drugs and pain intensity on movement were documented up to POD 5. RESULTS: Time required to walk more than 100 m without assistance was significantly shorter in the 120 h PCA group. Need for another analgesic regimen and pain score during the ambulation phase were significantly lower in the 120 h PCA than in the 40 h PCA group. Frequency of side effects was similar for both groups. CONCLUSION: Pain management using a PCA system can be recommended for patients during the ambulation period after cardiac surgery. Subcutaneous PCA with fentanyl is a safe and effective analgesic regimen for this purpose.

Ultrasound evidence of the optimal wrist position for radial artery cannulation.

PURPOSE: Radial artery cannulation is a common medical procedure for anesthesia and critical care. To establish the ideal wrist position for radial artery cannulation, we performed ultrasound examinations of the radial artery to investigate the effect of the angle of wrist extension on radial artery dimensions. CLINICAL FEATURES: Measurements were performed in 17 healthy subjects and 17 surgical patients scheduled for coronary artery bypass graft (CABG) surgery. The radial artery was echographically visualized near the styloid process of the radius at the wrist. Radial artery dimensions were measured at wrist joint angles of 0, 15, 30, 45, 60 and 75 degrees . OBSERVATIONS: In both groups, radial artery height was affected by the wrist joint angle. Vessel height was decreased at 60 degrees (one way ANOVA P = 0.027 vs 0 degrees ) and 75 degrees (P < 0.001 vs 0, 15, 45 degrees ) in healthy subject and at 75 degrees in CABG patients (P < 0.001 vs 0 degrees ). The mean differences in radial artery height at 0 and 75 degrees were 0.33 +/- 0.09 mm and 0.20 +/- 0.06 mm for healthy and CABG patients, respectively. Vessel width was not affected by wrist joint angulation up to 75 degrees of extension. CONCLUSION: Our results demonstrate that in healthy subjects, radial artery dimensions are unaltered when the wrist joint is extended up to an angle of 45 degrees . Extension at 60 degrees for healthy subjects and 75 degrees for CABG patients, however, results in a decrease in the height of the radial artery, which could possibly render arterial catheterization more difficult.

Movement Modifications Related to Psychological Pressure in a Table Tennis Forehand Task.

Although many studies on choking under pressure used closed skills, such as golf putting, we examined the influence of pressure on movement during a dynamic skill by studying participants' kinematic and kinetic changes during a table tennis forehand task under pressure. Thirty novice table tennis players hit forehand shots toward a target for 135 practice trials and then performed 10 no-pressure and 10 pressure trials. We added psychological pressure by instructing participants they could earn monetary rewards for successful performance and by cancelling accumulated scores for a poor performance. We measured racket head and ball movements as kinematic variables and grip force as a kinetic variable. We also measured state anxiety and heart rate as checks on our manipulation of psychological pressure. In the pressure condition, both state anxiety and heart rate increased significantly ( p < .025), though the pressure level was relatively small. Analysis of kinematic measures revealed that back swing and forward swing were reduced in length; speed of forward swing and ball speed decreased significantly ( p < .008) under pressure. Also, under pressure, ball and racket contact point shifted forward significantly ( p < .008) to reduce the distance between impact and target locations, and performance declined as the ball-landing locations shifted leftward ( p < .007). Grip force showed no significant change. We conclude that, under pressure, movement was modified toward reduced displacement and lower speed in an apparent risk-aversive hitting strategy; these modifications resulted in a performance decrement.

Evaluation of cuff-wrapping methods for the determination of ankle blood pressure.

OBJECTIVE: The ankle-brachial index, which is calculated by dividing ankle systolic blood pressure by brachial systolic blood pressure, is useful in diagnosing peripheral arterial disease. Consensus has not been reached, however, on a standard method for measuring ankle systolic blood pressure. This study evaluated two cuff-wrapping methods for measuring ankle systolic blood pressure, compared with intra-arterial pressure as a gold standard. METHODS: Study participants were 24 consecutive adult patients who underwent surgery under general anesthesia at Kyoto Prefectural University Hospital in Japan between January and March 2002. Indirect ankle systolic blood pressure was measured in the posterior tibial artery using a Doppler device and two cuff-wrapping methods: spiral, and straight. Direct ankle systolic blood pressure was measured in the dorsalis pedis artery. RESULTS: Mean difference in ankle systolic blood pressure between indirect and direct measurements (indirect minus direct) was 1.4 mmHg [standard deviation of the difference (SDd), 17.6 mmHg] with the straight method and -1.4 mmHg (SDd, 22.2 mmHg) with the spiral method. The limit of agreements (mean difference +/-2 SDd) and intraclass correlation coefficient between two observers were -17.6 to 20.1 mmHg and 0.94, respectively, for the straight method and -39.4 to 40.0 mmHg and 0.78, respectively, for the spiral method. CONCLUSIONS: The straight method, the same cuff-wrapping method used for measuring brachial blood pressure, appears to represent a more suitable wrapping method because of better interobserver reproducibility. Accuracy and reproducibility of indirect ankle systolic blood pressure measurement, however, were not adequately improved by either of the wrapping methods.

[Airway obstruction caused by massive swelling of the tongue following bilateral tonsillectomy for sleep apnea syndrome].

A case of airway obstruction caused by the tongue swelling is reported. The patient is a 5-year-old boy scheduled for bilateral tonsillectomy for sleep apnea syndrome. Anesthesia was slowly induced by sevoflurane and maintained with nitrous oxide, fentanyl and sevoflurane. Bilateral tonsillectomy and adenoidectomy were performed uneventfully under general anesthesia. The operation time was 2 hours and 30 minutes. Following the surgical procedure, the endotracheal tube was removed. Shortly after the extubation, the patient complained of difficult articulation and paradoxical respiration. Trachea was intubated immediately. Oxygen saturation was within normal limits throughout all the procedures. Swelling of the tongue was aggravated and was not relieved by steroid infusion. Massive swelling of the face and neck was observed on the next day. CT scan and fiberoptic scope examination showed the swollen tongue obstructing the upper airway. Additional administration of steroid was continued. On the third postoperative day, edema was relieved and the endotracheal tube was removed. Clinical course after the extubation was uneventful. No laboratory data was obtained suggesting the allergic basis. Extubation should be performed carefully and respiratory condition should be observed cautiously following the oral surgery of even a short duration.

Peripheral inflammation induces up-regulation of TRPV2 expression in rat DRG.

The transient receptor potential vanilloid subfamily member 2 (TRPV2) is a cation channel activated by temperatures above 52 degrees C. To analyze the contribution of TRPV2 to the development of inflammation-induced hyperalgesia, the expression of TRPV2 in primary sensory neurons was analyzed after intraplantar injection of complete Freund's adjuvant (CFA). Using specific antibodies, an increase in TRPV2-expressing neurons was identified after inflammation. TRPV2 expression is concentrated in a subset of medium-sized dorsal root ganglion neurons, independent of transient receptor potential vanilloid subfamily member 1 (TRPV1) expression. A similar distribution of TRPV2 was observed after inflammation. Intraplantar injection of nerve growth factor increased TRPV1 expression but not TRPV2, suggesting that induction of TRPV2 expression is driven by a mechanism distinct from that for TRPV1. Heat hyperalgesia assessment after chemical desensitization of TRPV1 by resiniferatoxin demonstrates a possible role for TRPV2 in inflammation at high temperatures (>56 degrees C). These results suggest that TRPV2 upregulation contributes to peripheral sensitization during inflammation and is responsible for pain hypersensitivity to noxious high temperature stimuli.

[Current status of pulmonary aspiration associated with general anesthesia: a nationwide survey in Japan].

BACKGROUND: Aspiration has been considered as a morbid complication of anesthesia. The current status of anesthesia-associated pulmonary aspiration, however, has not yet been assessed in modern Japanese anesthesia practices. METHODS: A written questionnaire was sent to all of the Japanese anesthesia-teaching hospitals certified by the Japan Society of Anesthesiologists and 56% of questionnaires were recovered and analyzed. RESULTS: In the year 2002, 58 cases of pulmonary aspiration were reported (approximately 0.8/ 10,000 anesthesia cases). Approximately one-third of patients with aspiration subsequently suffered severe pulmonary complications necessitating mechanical ventilation and/or admission to the intensive care unit. Mortality in patients with aspiration was 5% (3/57; 1/250,000 anesthesia cases). Predisposing factors of emergency abdominal surgery with bowel obstruction, but not short fasting period, appeared to be associated with occurrence of severe pulmonary aspiration. Unproven therapies for aspiration were frequently applied, including bronchial toileting, systemic high-dose steroids and prophylactic antibiotics. CONCLUSIONS: Aspiration remains a significant complication, even in modern anesthesia practices. Given the high morbidity and few proven therapies, nationwide clinical trials should be conducted and national therapeutic guidelines should be established in Japan.

[Perioperative management of a neonate with a retroperitoneal giant teratoma who underwent its extirpation under general anesthesia: a case report].

We gave anesthesia to a neonate with a retroperitoneal giant teratoma who underwent its extirpation. Even if patients have a prenatal diagnosis of teratoma like this case, there are many patients, especially infants, with severe general condition. We report the difficulty for management during anesthesia because of severe respiratory acidosis due to pressure from diaphragmatic pleura by tumor, severe circulatory disorder due to massive bleeding during operation and severe hyperkalemia due to renal failure.

Spinal Reflexes During Postural Control Under Psychological Pressure.

This study investigated the effect of psychological pressure on spinal reflex excitability. Thirteen participants performed a balancing task by standing on a balance disk with one foot. After six practice trials, they performed one nonpressure and one pressure trial involving a performance-contingent cash reward or punishment. Stress responses were successfully induced; state anxiety, mental effort, and heart rates all increased under pressure. Soleus Hoffmann reflex amplitude in the pressure trial was significantly smaller than in the nonpressure trial. This modification of spinal reflexes may be caused by presynaptic inhibition under the control of higher central nerve excitation under pressure. This change did not prevent 12 of the 13 participants from successfully completing the postural control task under pressure. These results suggest that Hoffmann reflex inhibition would contribute to optimal postural control under stressful situations.

Mechanism of suppression of insulin signalling with lignocaine.

Lignocaine suppresses insulin-stimulated glucose transport into the cells and insulin-stimulated glycogenesis at doses equivalent to that used in the treatment of muscle pain disorder. We evaluated the direct effect of lignocaine on insulin receptor (IR) kinase activity. After lignocaine (40 mM, approximately equivalent to 1%) or an equal volume (100 microl) saline had been injected into the tibialis anterior muscle of rat, insulin (50 mM g-1 body weight) was administered into the portal vein in vivo. Immunoprecipitation and immunoblotting were used to detect insulin-mediated tyrosine phosphorylation of both IR-beta and insulin receptor substrate (IRS)-1, and insulin-stimulated binding of IRS-1 to p85 regulatory subunit of phosphatidylinositol 3-kinase (PI3-K) in the extracted muscle. In the in vitro study, purified IR from rat liver and/or recombinant IRS-1 protein with adenosine triphosphate were incubated with lignocaine (4 or 40 mM). Lignocaine reduced insulin-stimulated tyrosine phosphorylation of IR-beta to 12.6+/-5.7% (P<0.001), and IRS-1 to 32.1+/-18.8% (P<0.01), and also reduced insulin-stimulated binding of IRS-1 to p85 to 27.4+/-12.7% (P<0.001) relative to control (100%) in muscle in vivo. The in vitro study revealed that lignocaine directly inhibited both basal and insulin-stimulated tyrosine phosphorylation of IR. These results indicate that clinically used doses of lignocaine inhibit insulin signalling in skeletal muscle. The inhibitory effect of lignocaine on tyrosine kinase activity of the IR underlies the suppression of insulin signalling with lignocaine.

Suppression of insulin signalling by a synthetic peptide KIFMK suggests the cytoplasmic linker between DIII-S6 and DIV-S1 as a local anaesthetic binding site on the sodium channel.

1. Acetyl-KIFMK-amide (KIFMK) restores fast inactivation to mutant sodium channels having a defective inactivation gate. Its binding site with sodium channels could be considered to be the cytoplasmic linker (III-IV linker) connecting domains III and IV of the sodium channel alpha subunit. There is a close resemblance of the amino-acid sequences between the III-IV linker and the activation loop of the insulin receptor (IR). This resemblance of the amino-acid sequences suggests that KIFMK may also modulate insulin signalling. In order to test this assumption, we studied the effects of KIFMK and its related (KIYEK, KIQMK, and DIYET) and unrelated (LPFFD) peptides on tyrosine phosphorylation or dephosphorylation of IR in vitro. 2. Purified IR was phosphorylated in vitro with insulin in the presence of various synthetic peptides and lignocaine. The phosphorylation level of IR was then evaluated after SDS-PAGE separation, followed by Western blot analysis with antiphosphotyrosine antibody. 3. KIFMK and KIYEK inhibited insulin-stimulated autophosphorylation of IR. Lignocaine showed similar effects, but at a higher order of concentration. KIYEK and DIYET, but not KIFMK, dephosphorylated the phosphorylated tyrosine residues. The structurally unrelated peptide LPFFD had no effect either on phosphorylation or dephosphorylation of IR. 4. These results indicate that KIFMK, KIYEK, and lignocaine bind with the autophosphorylation sites of IR. 5. The present findings also suggest that KIFMK and lignocaine bind with the III-IV linker of sodium channel alpha subunit.

Local inflammation increases vanilloid receptor 1 expression within distinct subgroups of DRG neurons.

Vanilloid receptor 1 (VR1) is essential to the development of inflammatory hyperalgesia. We investigated whether inflammation can increase in VR1 positive neuronal profiles in rat DRG neurons using histochemical methods. We also used size frequency analysis and double staining with several neuronal markers to investigate whether or not inflammation alters VR1 expression. Inflammation induced a 1.5-fold increase in percentage of VR1-like immunoreactivity (LI) positive profiles per total neuronal profiles, suggesting that the number of heat and pH sensitive neurons increase during inflammation. Area frequency histograms showed that VR1 expression increased in small and medium-sized neurons after inflammation. Double labeling of VR1 with NF200 showed that VR1 positive neurons with NF200 positive profiles significantly increased, indicating that the medium-sized VR1 positive neurons were neurons with myelinated A-fibers. Local inflammation thus increases in VR1 protein level within distinct subgroups of DRG neurons that may participate in the development and maintenance of inflammatory hyperalgesia.

The effects of neurosurgical stress on peripheral lymphocyte subpopulations.

STUDY OBJECTIVE: To observe changes in the peripheral lymphocyte subpopulations as an index of cellular immunity during neurosurgical procedures. DESIGN: Clinical study. SETTING: Operating room of a university hospital. PATIENTS: 11 patients with early intracranial disease who were scheduled to undergo elective neurosurgery with general anesthesia. Patients in the control group (n = 10) underwent minor surgeries such as ophthalmologic, otorhinolaryngological, or orthopedic surgeries. INTERVENTIONS: Blood was sampled before anesthesia induction (t0) for baseline and at 1 hour (t(1)) and 2 hours (t(2)) following surgical incision. MEASUREMENTS: Detection and quantification of lymphocyte subpopulations were performed at each time point using single-label and double-label analyses of monoclonal antibodies against lymphocyte membrane surface markers. MAIN RESULTS: Significant changes in patients who underwent a neurosurgical procedure included: the percentage of total T cells (CD3+) from 57.54 +/- 3.50% at t(0) to 51.41 +/- 4.26% at t(1) and 46.29 +/- 4.02% at t(2); the percentage of inducer T cells (CD4+, Leu8+) from 27.39 +/- 2.26% at t(0), to 23.26 +/- 2.30% at t(1) and 20.82 +/- 2.70% at t(2); the CD4/CD8 ratio, from 1.78 +/- 0.25% at t(0) to 1.35 +/- 0.12% at t(1) and 1.22 +/- 0.17% at t(2). The percentage of suppressor T cells (CD8+, Leu15+) increased significantly from 10.8 +/- 1.07% at t(0) to 13.64 +/- 1.62% at t(1), and 14.82 +/- 1.24% at t(2). The percentages of the natural killer cell subsets also increased significantly. Control group patients who underwent minor surgeries showed no significant changes. CONCLUSIONS: Neurosurgery-induced significant suppression of cellular immunity was demonstrated in peripheral lymphocyte subpopulations, probably from the surgical stress on the central nervous system.

Changes of oxygen transport variables and serum lactate during open-chest cardiac massage in dogs.

The aim of this study was to investigate the influence of critically low cardiac output (CO) upon oxygen transport. We especially focused on the changes of mixed venous oxygen saturation (S-vO2) in the presence of oxygen consumption ([Formula: see text]) debts. Additionally, we examined the correlation between the cumulative oxygen deficit (Def[Formula: see text]) and serum lactate. Def[Formula: see text] was calculated as the integrated area under the tissue[Formula: see text]) deficit (baseline[Formula: see text]-acutal[Formula: see text]) and time curve. To produce severe low CO, we performed openchest cardiopulmonary resuscitation (CPR) in 11 anesthetized dogs for 1 h. We made the measurements before (baseline values) and during the CPR at 10-min intervals. Supplydependent[Formula: see text] was observed when CO decreased below 40 ml·min-1·kg-1. The mean value of S-vO2 in the range of supply-dependent[Formula: see text] was 13±2% and did not change significantly during 1 h of CPR. The changes of lactate from baseline values were linearly correlated with Def[Formula: see text] (r=0.62,P<0.01), but absolute values of serum lactate were not.