Sympathovagal balance fluctuates during colonoscopy

Evaluation of a novel disposable endoscope for retroflexed endoscopic rubber band ligation of internal hemorrhoids: a randomized pilot study

PURPOSE

Retroflexed endoscopic rubber band ligation (ERBL) for treating Grade II and III internal hemorrhoids using disposable endoscopes has not been previously assessed. We therefore compared the safety and effectiveness of ERBL for internal hemorrhoids using novel disposable endoscopes versus traditional reusable endoscopes.

METHODS

This prospective randomized controlled trial involved 42 patients who underwent ERBL for Grade II and III internal hemorrhoids using either a disposable endoscope (n = 21) or a reusable endoscope (n = 21). Safety was assessed by the incidence of equipment failure, device-related adverse events, and in-procedure stability of vital signs. Effectiveness was assessed by the postoperative therapeutic effect, feasibility of retroflexed ERBL, and incidence of complications.

RESULTS

In terms of safety, no life-threatening events, equipment failure, or device-related adverse effects occurred during the procedures in either group. The rate of diastolic blood pressure stability was significantly different between the two groups (P = .049), but the rates of systolic blood pressure and heart rate stability were similar. In terms of effectiveness, the therapeutic effects on postoperative Day 30 were similar in both groups. Image clarity and endoscopic flexibility in the disposable endoscope group were mildly inferior to those in the reusable endoscope group, but without statistical significance. Matching between the endoscope and ligating device was 100% in both groups. The incidence of complications on postoperative Days 1 and 10 was not significantly different between the two groups.

CONCLUSION

Compared with reusable endoscopes, disposable endoscopes are equally safe, feasible, and reliable in ERBL for internal hemorrhoids.

Randomized controlled trial of effects of a familiarization video and patient-controlled Entonox inhalation on patient stress levels and clinical efficacy of flexible sigmoidoscopy without analgesia or sedation for investigation of fresh rectal bleeding

BACKGROUND AND AIM

Flexible sigmoidoscopy (FS) without analgesia or sedation can be unpleasant for patients, resulting in unsatisfactory examinations. Prior familiarization videos (FVs) and intra-procedural Entonox inhalation have shown inconsistent effects. This study investigated their effects on undesirable participant factors (anxiety, stress, discomfort, pain, satisfaction, later unpleasant recall of procedure, and vasovagal reactions) and clinical effectiveness (extent of bowel seen, lesions detected, and procedural/recovery times).

METHODS

This cluster-randomized single-center study evaluated 138 participants undergoing FS. There were 46 controls, 49 given access to FV, and 43 access to both FV and self-administered Entonox. Participant factors were measured by self-administered questionnaires, independent nurse assessments, and heart rate variability (HRV) metrics.

RESULTS

Questionnaires showed that the FV group was slightly more tense and upset before FS, but knowledge of Entonox availability reduced anxiety. Nonlinear HRV metrics confirmed reduced intra-procedural stress response in the FV/Entonox group compared with controls and FV alone (P < 0.05). Entonox availability allowed more bowel to be examined (P < 0.001) but increased procedure time (P < 0.05), while FV alone had no effect. FV/Entonox participants reported 1 month after FS less discomfort during the procedure. Other comparisons showed no significant differences between treatment groups, although one HRV metric showed some potential to predict vasovagal reactions.

CONCLUSIONS

Entonox availability significantly improved clinical effectiveness and caused a slight reduction in undesirable participant factors. The FV alone did not reduce undesirable participant factors or improve clinical effectiveness. Nonlinear HRV metrics recorded effects in agreement with stress reduction and may be useful for prediction of vasovagal events in future studies.

Autonomic nervous responses in colorectal polypectomy: Randomized controlled trial comparing air and carbon dioxide insufflation

BACKGROUND AND AIM

Carbon dioxide (CO2) insufflation devices are commonly used for endoscopic examination and treatment. In this prospective randomized controlled trial (RCT), we compared patient acceptance, cardiovascular tolerance,and autonomic nervous responses between patients receiving air insufflation and CO2 insufflation.

METHODS

We initially enrolled 170 patients and, of these, 158 patients in total were analyzed (air group, 83; CO2 group, 75). Autonomic nervous responses were evaluated by analysis of heart rate variability (HRV). Primary end point was superiority in the effects of CO2 insufflation on the autonomic nervous system by HRV analysis.

RESULTS

Visual analog scale disclosed significantly less abdominal pain and abdominal fullness with CO2. Percentage heart rate change rate at 1 h and 4 h after the procedure was also significantly lower in the CO2 group than in the air group (1 h after: P < 0.01, 4 h after: P < 0.05). Comparison based on age showed that % heart rate change was significantly lower in the younger CO2 patients (just after colonoscopy and 1 h after: P < 0.01, 4 h after: P < 0.05), but this difference was not apparent in an older group of patients.

CONCLUSIONS

This is the first RCT showing that colorectal polypectomy using CO2 insufflation significantly decreases abdominal pain and abdominal fullness common in such patients with lowered stress to the autonomous nervous system. The effects using CO2 insufflation on the sympathetic nervous system also seemed to be more prominent among younger patients.

Psychological adjustment and autonomic disturbances in inflammatory bowel diseases and irritable bowel syndrome

Psychological factors and the autonomic nervous system (ANS) are implicated in the pathogenesis of inflammatory bowel diseases (IBD) and irritable bowel syndrome (IBS). This study aimed to assess, firstly the way IBS and IBD patients cope with their pathology according to their affective adjustment and secondly the possible links between these affective adjustments and ANS reactivity. Patients with Crohn's disease (CD; n=26), ulcerative colitis (UC; n=22), or IBS (n=27) were recruited and compared to 21 healthy subjects based on psychological variables (trait- and state anxiety, depressive symptomatology, negative mood, perceived stress, coping, health locus of control) and sympatho-vagal balance through heart-rate variability monitored at rest. A principal component analysis, performed on all affective variables, isolated a leading factor labelled as "affective adjustment". In each disease, patients were distributed into positive and negative affective adjustment. In all the diseases, a positive affect was associated with problem-focused coping, and a negative affect with emotion-focused coping and external health locus of control. Results show that the sympatho-vagal balance varied according to the disease. In CD presenting positive affectivity, an adapted high sympathetic activity was observed. In UC, a parasympathetic blunt was observed in the presence of negative affectivity and an equilibrated sympatho-vagal balance in the presence of positive affectivity. In contrast, in IBS, an important dysautonomia (with high sympathetic and low parasympathetic tone) was constantly observed whatever the affective adjustment. In conclusion, this study suggests that the equilibrium of the ANS is differentially adapted according to the disease. This equilibrium is conjugated with positive affective and cognitive adjustment in IBD (CD and UC) but not in IBS.

Cardiac autonomic regulation during gastroscopy

BACKGROUND

Gastroscopy is sometimes associated with adverse cardiovascular events.

AIMS

We evaluated the effects of sedation and pharyngeal anaesthesia on cardiac autonomic regulation during gastroscopy.

PATIENTS

Two hundred thirteen outpatients undergoing gastroscopy.

METHODS

The patients were assigned to 4 groups: (1) sedation with intravenous midazolam and placebo throat spray (midazolam group), (2) placebo sedation and pharyngeal anaesthesia with lidocaine (lidocaine group), (3) placebo sedation and placebo throat spray (placebo group), and (4) no intravenous cannula nor throat spray (control group). Continuous electrocardiogram was recorded. Heart rate variability was assessed; the powers of low frequency (0.04-0.15 Hz) and high frequency (0.15-0.40 Hz) components as well as total power (0.0-0.4 Hz) were calculated.

RESULTS

Gastroscopy was associated with a decrease in high frequency normalized units, increases in low frequency normalized units and low frequency/high frequency ratio indicating activation of sympathetic and withdrawal of vagal modulation. Sympathetic activation resulted in a decrease in total power and all components of heart rate variability. The decrease was most prominent in the midazolam treated patients (p<0.001 vs the lidocaine group and p<0.01 vs placebo and control groups during the postendoscopy phase).

CONCLUSION

Gastroscopy induces a shift towards dominance of the sympathetic modulation of the heart. Premedication with midazolam potentiates this shift.

Cardiovascular considerations in patients undergoing gastrointestinal endoscopy

Gastrointestinal endoscopies are common procedures for diagnosis and treatment. Patients with various cardiovascular conditions can undergo these procedures, including those patients with acute myocardial infarction, but appropriate precautions need to be maintained, especially with procedure-induced autonomic nervous system pertubations that can affect heart rate and blood pressure. In this article, treatment recommendations are included for those patients undergoing endoscopy who are receiving anticoagulation and for those who are at risk for bacterial endocarditis.

Circadian variation of cardiac autonomic nervous profile is affected in Japanese ambulance men with a working system of 24-h shifts

OBJECT

The purpose of this study was to compare the stress levels of Japanese ambulance men between on-duty and off-duty days, by using the physiological indices of heart rate variability (HRV) and cortisol in urine, measured over each 24-h period.

METHODS

Measurements were made during one on-duty and one off-duty day for each subject. The participants were monitored for 24 h with a Holter recording system and a parameter reflecting overall stress levels was obtained by measuring the cortisol level in urine collected over 24 h.

RESULTS

The circadian variation of cardiac autonomic nervous system activity was affected when the subjects were on duty. The low-frequency/high-frequency power ratio (=low-frequency power/high-frequency power: LF/HF), which is a useful parameter that reflects the balance of cardiac autonomic nervous activity, differed significantly between the waking and sleeping times on the off-duty day (P=0.03), while it did not differ between these two states on the on-duty day (P=0.56). Similarly, the normalized high-frequency power [=high-frequency/(high-frequency+low-frequency) power: HF/(HF+LF)] ratio, which is a useful measure of the activity of the parasympathetic nervous system, differed significantly between these two states on the off-duty day (P=0.04), while there was no significant difference in the ratio between the two states on the on-duty day (P=0.13).

CONCLUSION

These results show that the diurnal balance of the cardiac autonomic nervous system is affected on the on-duty day, even though it is possible for ambulance men to sleep regular hours.