Inhalation analgesia with nitrous oxide versus other analgesic techniques in hysteroscopic polypectomy: a pilot study

Methoxyflurane analgesia for outpatient hysteroscopy: A double-blind, randomised, controlled trial

BACKGROUND

Despite clinical and economic benefits, pain during outpatient hysteroscopy (OPH) remains a barrier to use. There is a lack of evidence to support routine use of one analgesic over another versus no analgesic.

AIMS

To study the efficacy and safety of methoxyflurane analgesia during OPH.

MATERIALS AND METHODS

A single-centre, randomised, double-blind, placebo-controlled experiment was performed; 90 patients were randomly assigned (1:1). Participants allocated to the treatment group (cases) received 3 mL of methoxyflurane through an inhaler. The control group received a placebo. The primary outcome was a mean difference in pain, via a change in Visual Analog Scale (VAS) score from baseline at diagnostic hysteroscopy. Secondary outcomes were a mean difference in VAS score with any subsequent operative procedures; a mean difference in VAS score at 15 min post-procedure; participant and clinician-reported adverse effects and events; and participant-reported procedure acceptability, adjuvant nitrous oxide (N2O2) use and a composite of 'distress'.

RESULTS

During diagnostic hysteroscopy, there was a mean difference of 11.5 mm/100 (95% confidence interval (CI) 0.08-22.95), P = 0.05, with the lower score in the cases, compared with controls. During subsequent operative procedures, there was a mean difference of 15 mm/100 (95% CI 2.71-28.22), P = 0.02, with the lower pain score in the cases, compared with controls. There was no significant difference in pain 15 min post-procedure, participant- and clinician- reported adverse effects and events, procedure acceptability and the 'distress' composite.

CONCLUSIONS

Methoxyflurane significantly reduced pain during OPH compared with placebo, for diagnostic as well as operative procedures. Furthermore, methoxyflurane was well tolerated, with no adverse events.

Effectiveness of Nitrous Oxide versus Pethidine/Midazolam for Pain Relief in Minor Gynecological Operative Procedures: A Randomized Controlled Trial

Aim and Objective: To compare the analgesic effectiveness of the patient-controlled inhaled nitrous oxide (Entonox^®) with intravenous opioids (pethidine/midazolam) in reducing pain during minor gynecological operative procedures, including manual vacuum aspiration (MVA), fractional curettage and dilatation and curettage. Materials and Methods: Patients undergoing minor gynecological procedures from August 2021 to December 2022 were randomized to receive nitrous oxide or intravenous pethidine (50-75 micrograms) plus midazolam (2 mg). Pain scores during and post-procedure, satisfaction level, and side effects were assessed and compared. Results: A total of 106 patients met the inclusion criteria, including 53 in the pethidine/midazolam group and 53 in the nitrous oxide group. Baseline characteristics were comparable (p-value > 0.05). Pain scores during, immediately and 30 min after procedures were not significantly different in two groups (4.94 ± 3.15, 2.74 ± 2.57, 1.58 ± 2.13 vs. 5.47 ± 2.80, 2.98 ± 2.70, 1.64 ± 2.70; p-value: 0.174, 0.634, 0.889, for pethidine/midazolam vs. nitrous oxide group, respectively. Satisfaction scores were comparable in both groups (p-value > 0.05). However, the rate of side effects was significantly lower in the nitrous oxide group (3.8% vs. 28.3%; p-value 0.001). Additionally, the discharge scores showed a significantly faster recovery time in the nitrous oxide group at 60 and 90 min after the procedure; median (IQR): 10 (9-10) vs. 9 (8-10) and 10 (10-10) vs. 10 (8.5-10); p-value 0.002 and 0.029, respectively). Conclusions: Nitrous oxide is as effective as pethidine/midazolam for pain relief in minor gynecological operative procedures but associated with significantly lower side effects and significantly faster recovery time.

Opinion paper: gynecological surgery in local anesthesia?

Purpuse

The paracervical block (PCB) is a local anesthesia procedure that can be used to perform gynecological surgeries without the need for further anesthesia. With the PCB, surgeries can be moved from the central operating room to outpatient operating rooms, where they can be performed without the presence of an anesthesia team.

Methods

In this paper, the indications, implementation and limitations of the procedure are discussed.

Conclusion

Especially in times of scarce staff and OR resources during the Corona pandemic, OR capacity can be expanded in this way.

Nitrous Oxide Use for Intrauterine System Placement in Adolescents

STUDY OBJECTIVE

To evaluate the impact of nitrous oxide on patient-reported pain for placement of intrauterine systems (IUSs) in adolescents STUDY DESIGN: : Prospective observational study SETTING: : IUS placement in an ambulatory clinic compared with placement with nitrous oxide in a hospital-based sedation unit PARTICIPANTS: : English-speaking adolescents aged 12 to 20 presenting to a pediatric and adolescent gynecologist with a medical indication for IUS placement MAIN OUTCOME MEASURES: : Patient-reported procedural pain measured on a visual analog scale 2 minutes post IUS insertion procedure. Secondary outcome measurement of likelihood of recommending an IUS to a peer.

RESULTS

Seventy-four patients agreed to participate. Forty-five patients underwent IUS placement in the clinic. Controlling for age, history of dysmenorrhea, and body mass index, a significant time (change in reported pain scores pre- vs post IUS insertion) by treatment (nitrous oxide vs standard of care) interaction was observed for patient-reported pain (b = -29.32 mm, P < 0.01). Patients receiving nitrous oxide were more likely to recommend an intrauterine placement than patients who received the current standard of care for pain management (b = 0.47, P = 0.02) after controlling for age, baseline pain score, and dysmenorrhea history.

CONCLUSION

Patient-reported pain was attenuated for patients who received nitrous oxide relative to those who received standard IUS placement. Patient-reported satisfaction was higher for patients who received nitrous oxide relative to those who received standard IUS placement.

A virtual reality system for pain and anxiety management during outpatient hysteroscopy-A randomized control trial

BACKGROUND

Visual and acoustic virtual reality (VR) has been increasingly explored as a non-pharmacological tool for pain relief in clinical settings.

OBJECTIVE

We aimed to evaluate the effectiveness of VR as a distraction technique in the management of acute pain during operative hysteroscopy in the outpatient setting.

METHODS

A prospective, open-label, randomized control trial in a tertiary university-affiliated medical centre between April and August 2020. Overall, 82 women were randomly allocated to undergo operative hysteroscopy either with the use of VR (n = 44, study group) or with standard treatment (control group, n = 38). VR was applied throughout the procedure and no anaesthesia was given. The primary outcome measures included self-reported intraoperative pain. Other objectives included vital parameters as pulse rate (PR) and respiratory rate (RR) before and during the first 3 min of the procedure. Pain and anxiety outcomes were measured as numeric rating scores.

RESULTS

The baseline parameters were similar between groups. The mean duration for the procedure was 8.1 ± 3.2 vs. 7.3 ± 6.0 min for the study and the control groups (p = 0.23). There were no statistically significant differences between the reported pain scores during the procedure [median (interquartile range) 5.0 (3.0-7.2) vs. 5.0 (3.0-8.0), respectively; p = 0.67]. While neither intraoperative heart rate nor respiratory rate differed between groups [14.0 (13.0-16.0) vs. 14.0 (11.0-16.5); p = 0.77)], the increase of heart rate was found greater in the VR group [+7.0 (8.5) vs. +1.0 (12.2); p = 0.01].

CONCLUSION

VR was not effective in reducing pain during an outpatient operative hysteroscopy.

SIGNIFICANCE

The use of a Virtual reality system was found ineffective in reducing pain during and after an office operative hysteroscopy without anaesthesia, in a thorough examination of both continuous physiological parameters and women's self-reported measures.

Nitrous oxide versus lidocaine versus no analgesic for in-office hysteroscopy: a randomised clinical trial

OBJECTIVE

To compare the effect of inhaled nitrous oxide (INO) on pain control during in-office hysteroscopy with 1% lidocaine paracervical infiltration and no analgesic.

DESIGN

Single-blind stratified randomised clinical trial with masked assessment by a third party.

SETTING

Department of Obstetrics and Gynaecology in a Spanish hospital.

POPULATION

Women who underwent hysteroscopy.

METHODS

Patients were stratified into three groups according to the purpose of the hysteroscopy (biopsy, polypectomy or tubal sterilisation) and then assigned to different treatment groups through a permuted-blocks randomisation within strata. Pain scale was provided by a gynaecologist totally blinded to procedures and treatments. Effects were assessed using a one-way analysis of variance following an intention-to-treat approach.

MAIN OUTCOME MEASURES

Visual analogue scale (VAS) from 0 to 100 mm.

RESULTS

A total of 314 women were included: 105 to INO, 104 to 1% lidocaine and 105 to no analgesic. Baseline characteristics were comparable. Mean VAS score after the procedure was 34.7 ± 25.8 mm, 36.1 ± 22.9 mm (P = 1.0) and 47.3 ± 28.2 mm (P = 0.001) for INO, 1% lidocaine and no analgesic, respectively. No adverse events were reported in 91 (86.7%) patients in the INO group compared with 79 (76%) in the 1%-lidocaine group (P = 0.04) and 85 (81%) in the no-analgesic group (P = 0.26).

CONCLUSION

INO was as effective as 1% lidocaine in pain control for in-office hysteroscopy and was better tolerated. The no-analgesic group presented the poorer results, so was the least recommended clinical option.

Office hysteroscopy: back to the future!

Hysteroscopy and anesthesia have come a long way in the last 150 years. While traditionally performed in the operating theater under general anesthesia, the alternative approach - so-called 'office' hysteroscopy - has gained popularity in recent years. Supporters of this modality cite the 'see and treat' capabilities, avoidance of anesthesia, more rapid turn-around time, and favorable economics as advantages. On the other hand, some question the success rate, capabilities, and patient comfort levels as potential drawbacks. In this article, we review the evidence behind all of these points as well as the requirements for setting up an office hysteroscopy service.

Comparison of analgesic and anxiolytic effects of nitrous oxide in burn wound treatment: A single-blind prospective randomized controlled trial

AIM

We compared the effects of 50% N2O and N2O titration in burn management to alleviate pain and anxiety associated with burn dressing.

METHODS

In this single-blind prospective randomized controlled trial, 70 stable adult burn patients were randomized to 2 groups during May 2015 to January 2016. The experimental group was titrated with N2O ranging from 30% to the ideal sedation concentration before dressing change until the end. The control group was treated with 50% N2O 2 minutes before dressing change until the end. Pain, anxiety, vital signs, and the highest concentrations of N2O inhaled were recorded at 1 minute before N2O inhalation (T0), dismantling of outer (T1), inner dressings (T2), debridement (T3), drug-smearing (T4), bandaging (T5), and 10 minutes after completion of the procedure (T6).

RESULTS

The pain and anxiety scores in the experimental group performed significantly less than the control group during T2-T6. The systolic blood pressure in T2 and the heart rate at T2 and T3 varied significantly between the 2 groups. The highest N2O concentrations of the experimental group were mainly 60% to 70% at T2 (87.9%), T3 (87.9%), and T4 (81.8%).

CONCLUSION

N2O titration significantly reduced pain and anxiety in burn patients, with minimal side effects.

Safety and effectiveness of sedation analgesia with nitrous oxide vs intravenous anesthesia with propofol in gastroscopy

AIM

To compare the safety and effectiveness of sedation analgesia with nitrous oxide and intravenous anesthesia with propofol in gastroscopic examination.

METHODS

From september 2015 to may 2016, 400 patients who would undergo painless gastroscopy, met the ASA first-level and second-level classification standard, and had good tolerance to anesthesia and surgery were included and randomly divided into either a propofol group (n = 200) or a nitrous oxide group (n = 200). The two groups underwent gastroscopy with propofol intravenous anesthesia and nitrous oxide sedation analgesia, respectively.

RESULTS

Before and after examination, the heart rate, blood pressure and pulse oxygen saturation in the propofol group were significantly higher than those during gastroscopic examination (P < 0.05), while in the nitrous oxide group, the heart rate, blood pressure and pulse oxygen saturation during examination were significantly higher than those before examination. Propofol intravenous anesthesia in gastroscopy significantly inhibited cardiopulmonary function, while nitrous oxide did not. Adverse reactions in the nitrous oxide group were mainly nausea and retching (13%), and the rates of slow heart rate, low blood pressure, and low oxygen blood syndrome were significantly lower than those in the propofol group (P < 0.05). The time of sedative effect was significantly longer for propofol intravenous anesthesia than nitrous oxide sedation analgesia (P < 0.05).

CONCLUSION

Nitrous oxide sedation analgesia can quickly and effectively have a sedative and analgesic effect, but does not induce deep and long-term anesthesia and therefore shortens the recovery time for patients. Although both nitrous oxide conscious sedation analgesia and intravenous propofol used in painless gastroscopic examination are safe and effective, nitrous oxide conscious sedation analgesia has better security.

Magnetic resonance imaging for diagnosis and management of unruptured interstitial pregnancy

AIM

The aim of this study was to evaluate the value of magnetic resonance imaging (MRI) for the diagnosis and management of suspicious unruptured interstitial pregnancy.

MATERIAL AND METHODS

Only patients with unruptured interstitial pregnancy evaluated by MRI and observed for at least a year after surgery were included. Initial evaluation was performed by measurement of serum β-human chorionic gonadotrophin level and ultrasonography. In suspicious cases, emergency MRI was performed to diagnose interstitial pregnancies with the exclusion of rudimentary horn pregnancy and angular pregnancy. Three-dimensional computed tomographic (CT) angiography was additionally performed if the uteroplacental neovascularization needed to be evaluated. Then, management procedures were individually determined along with the need for preoperative transcatheter arterial chemoembolization for immediate devascularization, and for the local or systemic administration of methotrexate. Either laparoscopic cornuostomy or cornual resection was chosen to excise the gestational mass.

RESULTS

Five consecutive women with unruptured interstitial pregnancy were enrolled. One case each of rudimentary horn pregnancy and angular pregnancy was excluded. Three-dimensional CT angiography was performed in three cases due to increased vascular flow on color Doppler ultrasonography. Preoperative devascularization by transcatheter arterial chemoembolization was performed in two cases, in which a prominent neovascularized gestational mass was identified. Uterine preservation was achieved by cornuostomy or cornual resection in all cases. Two patients with a desire to become pregnant conceived spontaneously thereafter, followed by successful cesarean birth.

CONCLUSION

This small case series emphasizes that precise localization of gestational products in the interstitial portion of the fallopian tube by MRI can facilitate the minimally invasive management of unruptured interstitial pregnancy for uterine preservation.

Chronic pain relief after the exposure of nitrous oxide during dental treatment: longitudinal retrospective study

The objective was to investigate the effect of nitrous/oxygen in chronic pain. Seventy-seven chronic pain patients referred to dental treatment with conscious sedation with nitrous oxide/oxygen had their records included in this research. Data were collected regarding the location and intensity of pain by the visual analogue scale before and after the treatment. Statistical analysis was performed comparing pre- and post-treatment findings. It was observed a remarkable decrease in the prevalence of pain in this sample (only 18 patients still had chronic pain, p < 0.001) and in its intensity (p < 0.001). Patients that needed fewer sessions received higher proportions of nitrous oxide/oxygen. Nitrous oxide may be a tool to be used in the treatment of chronic pain, and future prospective studies are necessary to understand the underlying mechanisms and the effect of nitrous oxide/oxygen in patients according to the pain diagnosis and other characteristics.