An Overview of Labor Pain: Components and Stages of the Labor Process

Labor pain (LP) is unbearable and a major source of anxiety and stress. Painful uterine contractions cause hyperventilation in the mother, and because of augmented catecholamine concentration, both the mother and her fetus will be hypoxic. Effective analgesia provides protection from difficulties and ensures good results in both the mother and fetus. Hence, the control of pain should form an integral part of labor management at any level. This brief review aims to identify LP and its effects on fetus and mother, stages of delivery and labor process, and components of LP.

Psychophysiological responses to treadwall and indoor wall climbing in adult female climbers

The purpose of the study was to compare the psychophysiological response of climbers of a range of abilities (lower grade to advanced) when ascending identical climbing routes on a climbing wall and a rotating treadwall. Twenty-two female climbers (31.2 ± 9.4 years; 60.5 ± 6.5 kg; 168.6 ± 5.7 cm) completed two identical 18 m climbing trials (graded 4 on the French Sport scale) separated by 1 week, one on the treadwall (climbing low to the ground) and the other on the indoor wall (climbing in height). Indirect calorimetry, venous blood samples and video-analysis were used to assess energy cost, hormonal response and time-load characteristics. Energy costs were higher during indoor wall climbing comparing to those on the treadwall by 16% (P < 0.001, $$\upmu _{{\text{p}}}^{2}$$ μ p 2 = 0.48). No interaction of climbing ability and climbing condition were found. However, there was an interaction for climbing ability and post-climbing catecholamine concentration (P < 0.01, $$\upmu _{{\text{p}}}^{2}$$ μ p 2 = 0.28). Advanced climbers’ catecholamine response increased by 238% and 166% with respect to pre-climb values on the treadwall and indoor wall, respectively; while lower grade climbers pre-climb concentrations were elevated by 281% and 376% on the treadwall and indoor wall, respectively. The video analysis showed no differences in any time-motion variables between treadwall and indoor wall climbing. The study demonstrated a greater metabolic response for indoor wall climbing, however, the exact mechanisms are not yet fully understood.

Catecholamine Concentrations during and after Retroperitoneoscopic Adrenalectomies in Surgeon, Anaesthetist and Patients – how is physiological stress different from pathophysiological stress?

Background: During resections of phaeochromocytoma release of catecholamines can lead to excessive hypertension and arrhythmia. Therefore, these procedures can be stressful to surgeons and anaesthetists. It is completely unknown, how the excessive catecholamine concentrations in phaeochromocytoma patients relate to catecholamine concentrations of physiological stress of physicians and control patients undergoing adrenalectomy because of hormone inactive tumours. We measured catecholamine concentrations, heart rate and blood pressure in patients with phaeochromocytoma, incidentaloma, a surgeon and an anaesthetist. Methods: After approval of the local ethics committee, we measured metanephrine and normetanephrine plasma concentrations in 8 patients with phaeochromocytoma, 6 control patients with incidentaloma, one surgeon and one anaesthetist at rest, after incision, after 20 and 40 minutes of surgery, and in recovery. Moreover, blood pressure and heart rate were obtained. Results: Intraoperatively significant increases of blood pressure, metanephrine and normetanephrine were found in patients and surgeon. Significant increase of normetanephrine was also found in control patients. But catecholamine concentrations in patients with phaeochromocytoma were 18 to 42 times higher than in control patients and physicians. Heart rate analysis showed no significant results. Conclusion: During phaeochromocytoma resections significant increases in catecholamine concentration and blood pressure can be found in patients and physicians. The excessive increase of catecholamine concentrations in phaeochromocytoma patients, was not always reflected by a corresponding blood pressure increase. Interestingly, although catecholamine concentrations in phaeochromocytoma patients almost normalize directly after surgery, their blood pressure remains stable without the need for pharmacological support.

The Effects of a Marathon Effort on Psychomotor Performance and Catecholamine Concentration in Runners over 50 Years of Age

Long-distance running and, in particular, running marathons has become an increasingly popular activity among the elderly. The aim of the study was to examine the effects of a marathon effort on the psychomotor performance and catecholamine concentration in runners over 50 years of age. The participants were male runners (n = 28) who completed the 32nd Wrocław Marathon in Poland. The runners’ psychomotor performance was assessed on the basis of their choice reaction times (CRT), heart rate (HR) and running speed measurements. In addition, the adrenaline (A) and noradrenaline (NA) as well as lactate (LA) levels and anaerobic threshold (AT) were measured. The runners’ CRT after crossing the finish line was significantly longer by 50 ms (p < 0.05) in response to each emitted audiovisual stimulus, as compared with baseline. The mean running speed was reduced by 1 km/h between the first speed measurement (5th km of the run) and the last (42.195 km) (p < 0.05). The observed three-fold increase in adrenaline and noradrenaline levels indicates an intense activity of the sympathetic–adrenergic system. The cognitive function levels in the studied marathon runners returned to baseline after 30 min of recovery, and the function of the sympathetic–adrenergic system by seven days after completing the marathon race.

COMPARATIVE ASSESSMENT OF DIFFERENT TYPES OF LARYNGOSCOPES BLADES - MACINTOSH, MILLER AND MCCOY FOR LARYNGEAL VIEW AND PRESSOR RESPONSE

The laryngoscopy is known to have profound cardiovascular effects. This includes pressor response and tachycardia along with an increase in catecholamine concentration, mainly norepinephrine. The major cause of the sympathoadrenal response is believed to arise from stimulation of supraglottic region by laryngoscopic blade with tracheal tube placement and cuff inflation contributing little additional stimulation. Complications of pressor respo laryngoscopy include myocardial ischemia, cardiac failure, intracranial haemorrhage and increase in intracranial pressure. Hence the present study planned to evaluate the laryngeal view and pressor response by using three different blades – Macintosh, McCoy and Miller laryngoscopes. The study was planned in the Department of Anaesthesia in Andaman and Nicobar Islands Institute of Medical Science (ANIIMS), Port Blair India, From Jun 2016 to Jun 2017 . The 30 patient undergoing the Laryngoscopy were enrolled in the present study. For the 10 patients using the Macintosh Blade were divided in Group I. The next 10 patients using the Miller blade were considered in the Group II. The remaining 10 patients were studied by use of McCoy blade. The results in our study show that the MacCoy laryngoscope blade improves the visualization of the larynx and significantly attenuates haemodynamic parameters during laryngoscopy and intubation as compared to that with Macintosh laryngoscope blade. Keywords: Laryngoscopy, Intubation, pressor response, Macintosh, miller and Mccoy laryngoscopes, etc

Electrochemical quantification of transmitter concentration in single nanoscale vesicles isolated from PC12 cells

Vesicle impact electrochemical cytometry shows vesicular catecholamine concentration is relatively constant and independent of the vesicular size.

Pendrin localizes to the adrenal medulla and modulates catecholamine release

Pendrin ( Slc26a4) is a Cl−/HCO3− exchanger expressed in renal intercalated cells and mediates renal Cl− absorption. With pendrin gene ablation, blood pressure and vascular volume fall, which increases plasma renin concentration. However, serum aldosterone does not significantly increase in pendrin-null mice, suggesting that pendrin regulates adrenal zona glomerulosa aldosterone production. Therefore, we examined pendrin expression in the adrenal gland using PCR, immunoblots, and immunohistochemistry. Pendrin protein was detected in adrenal lysates from wild-type but not pendrin-null mice. However, immunohistochemistry and qPCR of microdissected adrenal zones showed that pendrin was expressed in the adrenal medulla, rather than in cortex. Within the adrenal medulla, pendrin localizes to both epinephrine- and norepinephrine-producing chromaffin cells. Therefore, we examined plasma catecholamine concentration and blood pressure in wild-type and pendrin-null mice under basal conditions and then after 5 and 20 min of immobilization stress. Under basal conditions, blood pressure was lower in the mutant than in the wild-type mice, although epinephrine and norepinephrine concentrations were similar. Catecholamine concentration and blood pressure increased markedly in both groups with stress. With 20 min of immobilization stress, epinephrine and norepinephrine concentrations increased more in pendrin-null than in wild-type mice, although stress produced a similar increase in blood pressure in both groups. We conclude that pendrin is expressed in the adrenal medulla, where it blunts stress-induced catecholamine release.