Hemodynamic and autonomic response to acute hemorrhage in streptozotocin-induced diabetic rats

<p>Abstract</p> <p>Background</p> <p>The various autonomic control systems lead to characteristic changes in heart rate (HR) and blood pressure (BP) during acute hemorrhage. However, cardiovascular autonomic neuropathy due to diabetes mellitus may interfere with the normal compensation for hemorrhage.</p> <p>Materials and methods</p> <p>A controlled graded bleeding (6 - 36% loss of estimated total blood volume: ETBV) was performed in streptozotocin-induced diabetic rats (STZ rats) under a conscious state. Hemodynamic and autonomic responses to acute hemorrhage were examined using analysis of BP-HR variability. The effects of dextran treatment after hemorrhage were also examined.</p> <p>Results</p> <p>A significant reduction in mean arterial pressure began at 12% ETBV loss in STZ rats and 18% in the control rats, respectively. When blood loss reached 18% of TEBV, the decrease in HR was prominent in STD rats due to the activation of a parasympathetic drive, as indicated by the increase in high frequency (HF; 0.75~3.0 Hz) power in HR variability, while in the control rats this response was not observed. The administration of dextran prevented the activation of the parasympathetic drive in STZ rats during hemorrhaging. In the control rats, the dextran treatment sustained the initial increase in HR with reduced HF power in HR variability.</p> <p>Conclusion</p> <p>STZ rats showed different hemodynamic and autonomic responses to acute hemorrhage from the control rats. STZ rats were prone to develop bradycardiac hypotension characterized by marked parasympathetic activation during hemorrhaging. This finding suggests enhancement of the Bezold-Jarisch reflex in STZ rats. Dextran treatment to maintain a normovolemic hemorrhage state inhibits this reflex.</p

Premedication with midazolam in intellectually disabled dental patients: intramuscular or oral administration? A retrospective study

Background: The use of midazolam for dental care in patients with intellectual disability is poorly documented. The purpose of this study was to determine which method of premedication is more effective for these patients, 0.15 mg/kg of intramuscular midazolam or 0.3 mg/kg of oral midazolam. Material and Methods: This study was designed and implemented as a non-randomized retrospective study. The study population was composed of patients with intellectual disability who required dental treatment under ambulatory general anesthesia from August 2009 through April 2013. Patients were administered 0.15 mg/kg of midazolam intramuscularly (Group IM) or 0.3 mg/kg orally (Group PO). The predictor variable was the method of midazolam administration. The outcome variables measured were Observer’s Assessment of Alertness/ Sedation (OAA/S) Scale scores, the level of cooperation when entering the operation room and for venous cannulation, post-anesthetic agitation and recovery time. Results: Midazolam was administered intramuscularly in 23 patients and orally in 21 patients. More patients were successfully sedated with no resistance behavior during venous cannulation in Group PO than in Group IM ( p =0.034). There were no differences in demographic data and other variables between the groups. Conclusions: The results of this study suggest that oral premedication with 0.3 mg/kg of midazolam is more effective than 0.15 mg/kg of midazolam administered intramuscularly, in terms of patient resistance to venous cannulation. If both oral and intramuscular routes of midazolam are acceptable in intellectually disabled patients, the oral route is recommended

Effectiveness of dexmedetomidine for emergence agitation in infants undergoing palatoplasty: a randomized controlled trial

OBJECTIVES: In infants, there is a high incidence of emergence agitation (EA) after sevoflurane (Sev) anesthesia. This study aimed to test the hypothesis that dexmedetomidine (Dex) administration would reduce the incidence and severity of EA after Sev-based anesthesia in infants undergoing palatoplasty. METHODS: A prospective randomized clinical trial was conducted with 70 patients undergoing palatoplasty, aged 10-14 months. Infants were randomly allocated into two groups: Dex (n = 35) and saline (n = 35). In the Dex group, Dex (6 µg/kg/h) was administered approximately 10 min before the end of the surgery for 10 min, followed by 0.4 µg/kg/h until 5 min after extubation. In the saline group, an equivalent amount of saline was administered in a similar manner. After the surgery, patients were transferred to the postanesthetic care unit (PACU). The infant's behavior and pain were assessed with scoring system for EA (5-point rating scale) and pain scale (PS; 10-point rating scale), respectively. EA and PS were estimated at six time points (after extubation, leaving the operating room, 0, 30, 60, and 120 min after arrival in PACU). RESULTS: EA and PS scores were significantly lower in the Dex group than in the saline group from extubation to 120 min after arrival in PACU. CONCLUSIONS: Dex administration has the advantage of a reduced EA and PS without any adverse effects. Dex provided satisfactory recovery in infants undergoing palatoplasty

Usefulness of Airway Scope for intubation of infants with cleft lip and palate–comparison with Macintosh laryngoscope: a randomized controlled trial

Abstract Background Airway Scope (AWS) with its plastic blade does not require a head-tilt or separate laryngoscopy to guide intubations. Therefore, we hypothesized that its use would reduce the intubation time (IT) and the frequency of airway complication events when compared with the use of Macintosh Laryngoscope (ML) for infants with cleft lip and palate (CLP). Methods The parents of all patients provided written consents; we enrolled 40 infants with CLP (ASA-PS 1). After inducing general anesthesia using sevoflurane and rocuronium, we performed orotracheal intubations using either AWS (n = 20) or ML (n = 20), randomly. We define the duration between manual manipulation using cross finger for maximum mouth opening and the first raising motion of the chest following intubation by artificial ventilation as “IT;” further, the measured IT as primary outcomes. Airway complications were considered secondary outcomes. Moreover, we looked for associations between IT and the patient’s characteristics: extensive clefts, age, height, and weight. We used the Mann–Whitney test and Fisher’s exact probability test for statistical analysis; p < 0.05 was considered as statistically significant. Results The mean IT was 31.5 ± 8.3 s in AWS group and 26.4 ± 8.9 s in ML group. Statistical significant difference was not found in IT between the two groups. The IT of AWS group was statistically related to extensive clefts. Airway complications were detected in ML group. Conclusion AWS could be useful for intubation of infants with CLP; it required IT similar to that required using ML, with a lower rate of airway complications. Trial registration UMIN-CTR Registration number UMIN000024763. Registered 8 November 2016

Influence of acute progressive hypoxia on cardiovascular variability in conscious spontaneously hypertensive rats

The purpose of this study is to examine the influence of acute progressive hypoxia on cardiovascular variability and striatal dopamine (DA) levels in conscious, spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). After preparation for measurement, the inspired oxygen concentration of rats was decreased to 10% within 5 min (descent stage), maintained at 10% for 10 min (fixed stage), and then elevated back to 20% over 5 min (recovery stage). The systolic blood pressure (SBP) and heart rate (HR) variability at each stage was calculated to evaluate the autonomic nervous system response using the wavelet method. Striatal DA during each stage was measured using in vivo microdialysis. We found that SHR showed a more profound hemodynamic response to progressive hypoxia as compared to WKY. Cardiac parasympathetic activity in SHR was significantly inhibited by acute progressive hypoxia during all stages, as shown by the decrease in the high frequency band of HR variability (HR-HF), along with transient increase in sympathetic activity during the early hypoxic phase. This decrease in the HR-HF continued even when SBP was elevated. Striatal DA levels showed the transient similar elevation in both groups. These findings suggest that acute progressive hypoxic stress in SHR inhibits cardiac parasympathetic activity through reduction of baroreceptor reflex sensitivity, with potentially severe deleterious effects on circulation, in particular on HR and circulatory control. Furthermore, it is thought that the influence of acute progressive hypoxia on striatal DA levels is similar in SHR and WKY

The usefulness of the McGrath MAC laryngoscope in comparison with Airwayscope and Macintosh laryngoscope during routine nasotracheal intubation: a randomaized controlled trial

Abstract Background McGrath MAC video laryngoscope offers excellent laryngosopic views and increases the success rate of orotracheal intubation in some cases. The aim of this study was to determine the usefulness of McGrath MAC for routine nasotracheal intubation by comparing McGrath MAC with Airway scope and Macintosh laryngoscope. Methods A total of 60 adult patients with ASA physical status class 1 or 2, aged 20–70 years were enrolled in this study. Patients were scheduled for elective oral surgery under general anesthesia with nasotracheal intubation. Exclusion criteria included lack of consent and expected difficult airway. Patients were randomly allocated to three groups: McGrath MAC (n = 20), Airway scope (n = 20), and Macintosh laryngoscope (n = 20). After induction, nasotracheal intubation was performed by six expert anesthesiologists with more than 6 years of experience. Results There were no significant differences in preoperative airway assessment among the three groups. Successful tracheal intubation time was 26.8 ± 5.7 (mean ± standard deviation) s for McGrath MAC, 36.4 ± 11.0 s for Airway scope, and 36.5 ± 8.9 s for Macintosh laryngoscope groups. The time for successful tracheal intubation for McGrath MAC group was significantly shorter than that for Airway scope and Macintosh laryngoscope (p < 0.01). McGrath MAC significantly improved the Cormack Lehane grade for nasotracheal intubation compared with Macintosh laryngoscope (p < 0.05). Conclusion McGrath MAC significantly facilitates routine nasotracheal intubation compared with Airwayscope and Macintosh laryngoscope by shortening the tracheal intubation time and improving the Cormack Lehane grade. Trial registration UMINCTR Registration number UMIN000023506 . Registered 5 Aug 2016

General anesthetic management of a patient with multiple chemical sensitivity for oral surgery: a case report

Abstract Background Multiple chemical sensitivity (MCS) was first described in 1987. It is said that MCS is caused by neurological and immunological mechanisms in addition to psychosomatic mechanisms. When performing general anesthesia in patients with MCS, careful perioperative management is necessary. Case presentation The patient was a 32-year-old man. Wisdom teeth extraction under general anesthesia was scheduled under the diagnosis of pericoronitis. In 2015, he was diagnosed with MCS. Since then, he experienced sweating and urticaria when exposed to artificial fragrances. We prepared the surgical surroundings by letting the patient touch every possible equipment. In selecting the anesthetic drugs, a completely intravenous route was selected because of the possibility that artificial fragrance of inhalation anesthesia could induce symptoms. There was no allergic reaction during the preoperative period. Conclusions It is important to reduce psychological burden of patient and to eliminate all possible reactive substances to prevent symptom onset