Retrolaminar versus epidural block for postoperative analgesia after minor video-assisted thoracic surgery: a retrospective, matched, non-inferiority study.

BACKGROUND: The role of thoracic epidural analgesia (TEA) for postoperative analgesia after video-assisted thoracic surgery (VATS) is still controversial. Some studies have reported the efficacy of ultrasound-guided retrolaminar block (RLB) for the postoperative management of pain after chest wall surgery. The purpose of this study was to compare the postoperative analgesic efficacy and adverse effects of ultrasound-guided RLB with those of TEA in patients undergoing minor VATS procedures. METHODS: A total of 192 relevant records of patients were enrolled in this study. We reviewed electronic medical records of patients undergoing minor VATS procedures under general anesthesia. The primary outcome was the median differences in the numerical rating scale (NRS) scores during rest between the groups at the morning of postoperative day 1 (POD 1m). A propensity-matched analysis incorporating preoperative variables was used to compare the efficacy of postoperative analgesia in two groups. RESULTS: Overall, 94 patients were identified for analysis. Propensity score matching resulted in 47 patients in each group. There were no significant differences in the NRS scores between the two groups. The median differences in NRS scores during rest between the two groups at POD 1m were under 1, which indicates non-inferiority of RLB. There were no significant differences in the incidence of adverse effects and rescue dose of analgesic consumption between the two groups. CONCLUSIONS: The analgesic effects of continuous ultrasound-guided RLB were non inferior to those of TEA for minor VATS procedures.

Complete atrio-ventricular block with coronary artery spasm due to direct laryngoscopy in a pediatric patient with laryngeal papillomatosis: a case report.

BACKGROUND: Coronary artery spasm has rarely been reported in pediatric patients. Previous studies have reported comorbidities and risk factors for coronary artery spasms. We present the case of a complete atrio-ventricular (AV) block that occurred in the absence of other risk factors immediately after direct laryngoscopy. CASE PRESENTATION: A 2-year-old girl developed severe coronary artery spasm after direct laryngoscopy for elective laryngeal papillomatosis resection. Immediately after the initiation of laryngoscopy, complete AV block and ST elevation on lead II of the electrocardiogram were observed. These findings indicated that the complete AV block was caused by a right coronary artery spasm. CONCLUSION: Coronary artery spasm resulting in lethal arrhythmia rarely occurs in healthy pediatric patients. To the best of our knowledge, this is the first pediatric case of a severe coronary artery spasm resulting in a complete AV block due to direct laryngoscopy in a healthy patient.

Activation of mineralocorticoid receptors in the rostral ventrolateral medulla is involved in hypertensive mechanisms in stroke-prone spontaneously hypertensive rats.

Mineralocorticoid receptor (MR) is recognized as a target for therapeutic intervention in hypertension and heart failure. MRs in the central nervous system are thought to have an important role in blood pressure regulation. Thus, we examined whether activation of the MR pathway in the rostral ventrolateral medulla (RVLM) of the brainstem contributes to the neural mechanism of hypertension in stroke-prone spontaneously hypertensive rats (SHRSPs). We microinjected eplerenone, aldosterone or Na(+)-rich artificial cerebrospinal fluid (aCSF) into the RVLM of anesthetized Wistar-Kyoto (WKY) rats and SHRSPs. Arterial pressure (AP), heart rate (HR) and renal sympathetic nerve activity (RSNA) were recorded. The expressions of the MR protein and the serum- and glucocorticoid-regulated kinase protein (Sgk1), which is a marker of MR activity, in the RVLM were measured by western blot analysis. Bilateral microinjection of eplerenone into the RVLM decreased AP and RSNA in WKY rats and SHRSPs, and the decreases in those variables were significantly greater in SHRSPs than WKY rats. Microinjection of aldosterone or Na(+)-rich aCSF into the RVLM increased AP and RSNA dose-dependently. The increases in those variables were significantly greater in SHRSPs than in WKY rats. The pressor responses of aldosterone or Na(+)-rich aCSF were attenuated by the prior injection of eplerenone in SHRSPs. Sgk1 expression levels in the RVLM were significantly greater in SHRSPs than in WKY rats. These findings suggest that activation of MRs in the RVLM enhances sympathetic activity, thereby contributing to the neural mechanism of hypertension in the SHRSP.

Role of angiotensin-(1-7) in rostral ventrolateral medulla in blood pressure regulation via sympathetic nerve activity in Wistar-Kyoto and spontaneous hypertensive rats.

Angiotensin (Ang)-(1-7) Ang-(1-7) is formed from angiotensin II by angiotensin-converting enzyme 2 (ACE2) and modulates the renin-angiotensin system. We evaluated whether the Ang-(1-7)-Mas axis in the rostral ventrolateral medulla (RVLM) contributes to neural mechanisms of blood pressure (BP) regulation. We microinjected Ang-(1-7), Ang-(1-7)-Mas receptor antagonist A-779, and ACE2 inhibitor DX600 into the RVLM of anesthetized Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHRs). Unilateral Ang-(1-7) microinjection induced a significantly greater increase in AP (arterial blood pressure) in SHR than in WKY. Bilateral A-779 microinjection induced a significantly greater decrease in AP and renal sympathetic nerve activity in SHR than in WKY. Bilateral DX600 microinjection induced a significantly greater decrease in AP in SHR than in WKY. Our results suggest that endogenous Ang-(1-7) in the RVLM contributes to maintain AP and renal sympathetic nerve activity both in SHR and WKY and that its activity might be enhanced in SHR.

[Blocking effect of remifentanil on sympathetic response to tracheal intubation during sevoflurane anesthesia].

BACKGROUND: We examined the hemodynamic responses to tracheal intubation during anesthetic induction by inhalational sevoflurane with continuous administration of remifentanil. METHODS: This study enrolled 30 ASA physical status 1-2 patients, aged 20-65 undergoing elective surgical procedure. Anesthesia was induced with 5% sevoflurane in all patients, and then adjusted to maintain BIS values ranging from 40 to 60. Remifentanil at the rate of 0.5 microg x kg(-1) x min(-1) was administrated continuously, and tracheal intubation was performed by each anesthesiologist, at various times after administration of remifentanil. We recorded blood pressure (BP), heart rate (HR) and the duration between the initiation of an administration of remifentanil and a tracheal intubation (DRI). Sympathetic response to tracheal intubation was defined as more than 20% increase in either BP or HR at the intubation compared with that at preintubation. We analyzed the P50, representing the duration of remifentanil infusion with 50% probability of blocking sympathetic response to tracheal intubation. RESULTS: DRI for individual patients varied from 77 sec up to 660 sec. According to the present data, P50 was calculated as 210 +/- 16.4 sec (mean +/- SD). CONCLUSIONS: During sevoflurane anesthesia, remifentanil infusion at 0.5 microg x kg(-1) x min(-1) for more than 210 sec could provide the effective blocking of the sympathetic response to tracheal intubation with more than 50% probability.

[Report of an inquiry about epidural anesthesia for abdominal aortic aneurysm surgery in Japan].

BACKGROUND: Recently there are growing number of patients suffering from the abdominal aortic aneurysm (AAA), and we have many occasions to anesthetize these patients under coagulation therapy as well. Moreover, the risk of epidural hematoma increases when the operation of the AAA is performed with epidural technique because the operation is usually done with perioperative heparinization. For these reasons, we investigated the current situations of clinical practice in Japan in terms of the epidural anesthesia for AAA surgeries. METHODS: The questionnaires were sent to all 998 Japanese Society of Anesthesiologists certified training hospitals in October 2005, anonymously asking about current practices concerning AAA cases, anesthetic managements, use of epidural anesthesia and the experience of any complications. Fifty one per cent of the total questionnaires were returned and 94% of them could be analyzed. Seventeen per cent of responders were from university institutes or university related hospitals and 75% of them were from general hospitals of secondary critical care centers. RESULTS: This survey showed that the operations of AAA were done at 308 (64% of the responders) hospitals and the total number of AAA surgeries carried out was estimated to be 6,321 the last year. This figure was very close to the number announced by Japan Society of Cardiothoracic Surgeons. The epidural anesthesia was routinely used for AAA surgeries with general anesthesia in 224 hospitals (64%), but it was not used in 51 hospitals (14%). The standard protocol for the application of epidural anesthesia had been installed in 56% of hospitals and mostly in 187 hospitals (as several answers can be chosen). The epidural catheters were inserted the day before operation. There were 113 hospitals in which less than 2 hours was required from epidural puncture to heparinization, but in 141 hospitals it took more than 12 hours. However, on the contrary, many anesthetists answered that the risk of the epidural hematoma had been the cause of not routinely using the epidural anesthesia in AAA operations. We had 30 hospitals in which epidural hematoma had occurred in the cases not limited to AAA surgery and 17 cases of them resulted in severe complications afterwards. CONCLUSIONS: This investigation clarified the current situations of the clinical practice in Japan of the use of epidural anesthesia for AAA surgeries.