Entonox® inhalation to reduce pain in common diagnostic and therapeutic outpatient urological procedures: a review of the evidence

Clinical assessment and risk stratification for prehospital use of methoxyflurane versus standard analgesia in adult patients with trauma pain

Oligoanalgesia, the undertreatment of trauma-related pain using standard analgesics in prehospital and emergency departments, has been extensively documented as one of the major challenges affecting the effective treatment of trauma-related pain. When administered in low doses, methoxyflurane has been highlighted by numerous medical works of literature to provide an effective, nonopioid, nonnarcotic treatment alternative to standard analgesics for prehospital and emergency department use. Low-dose methoxyflurane has been associated with fast-pain relief in adult patients manifesting moderate-to-severe pain symptoms. This systematic review and meta-analysis aimed to assess the clinical implication of low-dose methoxyflurane use in prehospital and emergency departments in adult patients with moderate-to-severe trauma-related pain. Moreover, the review aimed at assessing the risk stratification associated with using low-dose methoxyflurane in prehospital and emergency departments. The systematic review and meta-analysis performed a comprehensive search for pertinent literature assessing the implications and risks of using low-dose methoxyflurane in adult patients exhibiting moderate-to-severe trauma-related pain in prehospital settings. A comparison between the use of low-dose methoxyflurane and standard-of-care analgesics, placebo, in prehospital settings was reported in four clinically conducted randomized controlled trials (RCTs). These RCTs included the STOP! trial, InMEDIATE, MEDIATA, and the PenASAP trials. A meta-analysis comparing the time taken to achieve first pain relief on initial treatment of patients with moderate-to-severe trauma-related pain favored the use of low-dose methoxyflurane to the standard-of-care analgesics (mean difference = -6.63, 95% confidence interval = -7.37, -5.09) on time taken to establish effective pain relief. Low-dose methoxyflurane has been associated with superior and faster pain relief in prehospital and emergency departments in adult patients exhibiting moderate-to-severe trauma-related pain compared to other standard analgesics.

Pain reduction methods during transurethral cystoscopy

Transurethral cystoscopy (CS) is a common urological procedure, performed mostly for diagnostic but also for therapeutic purposes. Although CS is generally well tolerated, some patients describe the pain related to the procedure as high or even “unbearable”. As a result, many patients fear and avoid both primary and/or follow-up cystoscopies. This may lead to uncontrolled progression of neoplastic disease. Therefore, it is crucial to maximally increase the comfort of the patient and to implement safe and effective analgesia before the procedure. Providing the patients with appropriate care during CS can encourage them to comply with diagnostic schedules and improve their prognosis. The aim of this review is to analyze the available literature on various methods of pain reduction during transurethral CS. The PubMed electronic database limited to English articles published until January 2021 was used in the process. Meta-analyses, systematic reviews, randomized controlled trials, clinical trials, prospective randomized studies, multicenter comparisons, reviews and retrospective comparisons were used. As a result, 65 articles were included in this review.

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.

Analgesic Efficacy, Practicality and Safety of Inhaled Methoxyflurane Versus Standard Analgesic Treatment for Acute Trauma Pain in the Emergency Setting: A Randomised, Open-Label, Active-Controlled, Multicentre Trial in Italy (MEDITA)

INTRODUCTION

Inhaled low-dose methoxyflurane is approved in Europe for emergency relief of moderate-to-severe trauma-related pain in adults, but data versus active comparators are sparse. The phase IIIb Methoxyflurane in Emergency Department in ITAly (MEDITA) trial investigated the analgesic efficacy, practicality and safety of methoxyflurane versus standard analgesic treatment (SAT) for acute trauma pain.

METHODS

This was a randomised, active-controlled, parallel-group, open-label trial conducted in 15 Italian emergency units. Adults with limb trauma and pain score ≥ 4 on numerical rating scale (NRS) were randomised 1:1 to inhaled methoxyflurane 3 mL or SAT [intravenously administered (IV) morphine 0.1 mg/kg for severe pain (NRS ≥ 7); IV paracetamol 1 g or IV ketoprofen 100 mg for moderate pain (NRS 4-6)]. The primary endpoint was overall change in visual analogue scale (VAS) pain intensity from baseline (time of randomisation) to 3, 5 and 10 min. Non-inferiority and superiority of methoxyflurane versus SAT were concluded if the upper 95% confidence interval (CI) for the treatment comparison (methoxyflurane-SAT) was less than 1 and less than 0, respectively.

RESULTS

Between 8 February 2018 and 8 February 2019, 272 patients were randomised (136 per treatment group). A total of 270 patients (mean age 51 years; 49% male; 34% with severe pain; mean baseline VAS 67 mm) were treated and analysed for efficacy and safety. Superiority of methoxyflurane was demonstrated for moderate-to-severe pain (adjusted mean treatment difference - 5.94 mm; 95% CI - 8.83, - 3.06 mm), moderate pain (- 5.97 mm; 95% CI - 9.55, - 2.39 mm) and severe pain (- 5.54 mm; 95% CI - 10.49, - 0.59 mm). Median onset of pain relief was 9 min for methoxyflurane and 15 min for SAT. Practicality of methoxyflurane treatment was rated "Excellent", "Very Good" or "Good" by 90% of clinicians vs. 64% for SAT. Adverse events (all non-serious) were reported by 17% of methoxyflurane-treated patients and 3% of SAT-treated patients.

CONCLUSION

Methoxyflurane provided superior pain relief to SAT in patients with moderate-to-severe trauma pain and may offer a simple, fast, effective non-opioid treatment option.

TRIAL REGISTRATION

Trial registered with EudraCT (2017-001565-25) on 2 March 2018 and ClinicalTrials.gov (NCT03585374) on 13 July 2018.

FUNDING

Mundipharma Pharmaceuticals S.r.l.

[Evaluation of protocols on the use of analgesics for pain management in patients with extracorporeal shock wave lithotripsy (ESWL)]

La douleur ressentie au cours d'une séance de lithotritie extracorporelle (LEC) est le facteur limitant le plus important de cette technique. Le but de notre travail était de comparer l'efficacité des différents types d'analgésiques utilisés pour le contrôle de la douleur pendant les séances de LEC. Nous avons mené une étude prospective colligeant 300 patients présentant une lithiase urinaire justifiant un traitement par LEC. Les patients ont été répartis de façon randomisée en trois groupes: le groupe I, incluant 100 patients ayant reçu 2cc de sérum physiologique en IM (intra musculaire) (placebo), le groupe II regroupant 100 patients ayant reçu 100mg de kétoprofène en IM tandis que le groupe III colligeant 100 patients ayant eu une application locale d'une crème contenant la lidocaïne et la prilocaïne. L'échelle visuelle analogique (EVA) a servi à évaluer la douleur à 10 minutes et à la fin de la séance. L'EVA moyenne à 10 minutes et à la fin de la LEC étaient respectivement de 3,7 et 4,91. Aucune différence significative n'a été trouvée entre les trois groupes concernant: les données épidémiologiques (âge, sexe, IMC, antécédents pathologies) et les caractéristiques du calcul (côté, taille, localisation, présence ou non de sonde double J). L'interruption précoce de la séance de LEC a été notée chez 11 patients du groupe I, avec une différence significative par rapport aux autres groupes (p=0,003). L'EVA à 10 minutes et à la fin de séance de LEC, était statistiquement plus élevée dans le groupe I par rapport aux groupes II et III (p < 0,001). Aussi, la LEC était nettement plus efficace dans les groupes (II et III) comparativement au groupe I (p<0,001). L'utilisation d'un traitement antalgique est nécessaire lors de la séance de lithotritie extracorporelle. Les deux molécules antalgiques évaluées ont montré un bon contrôle de la douleur ainsi qu'une augmentation de l'efficacité du traitement par lithotritie.

French clinical guidelines for peripheral motor nerve blocks in a PRM setting

INTRODUCTION

Motor nerve blocks with anesthetic drug for local anesthesia are commonly used in physical and rehabilitation medicine (PRM), especially in the field of spasticity. Guidelines in this context are currently lacking.

METHOD

Eighteen experts selected on the basis of their recognized experience by the scientific committees of the French PRM (SOFMER) and Anesthesia and Intensive care (SFAR) societies were invited to work and propose guidelines for the use of loco-regional anesthetic drug for motor nerve blocks in PRM setting. Eight issues were addressed: which neural blocks for which indications; drugs and contraindications; medical survey and attitude in case of adverse event; injection and guidance material; patient preparation and pain relief; efficacy assessment; patient information; education of PRM physiatrists. The Medline, Cochrane and Embase databases for the period 1999 to 2018 were consulted and 355 papers analyzed. The drafts were commented then approved by the whole group using electronic vote, before final approval by scientific committee of each society.

RESULTS

No scientific evidence emerged from the literature. Thus, these guidelines are mainly based on the opinion of the expert panel. Guidelines for each issue are reported with the main points of arguments. The main question deals with the recommendation about doses for each drug: for lidocaine - up to 2mg/kg - "check contraindications, emergency truck available, no need of previous anesthetic consultation nor presence of anesthetic physician"; for ropivacaine - up to 1.5mg/kg, with a maximum of 100mg - the same but after intravenous line. Beyond these doses, SFAR guidelines have to be applied with the need of anesthetic physician.

CONCLUSION

These are the first organizational guidelines devoted to increase the security of motor nerve block use in PRM settings.

Procedural pain management in patients with cancer

Pain has been identified as one of the most significant factors in patients' experience of cancer and its treatment. Pain experienced during cancer treatment procedures such as radiotherapy can be unpleasant and distressing for the patient, as well as for their family and carers. Nurses have an important role in assessing and managing any pain associated with such procedures. This article explores the procedural pain that may be experienced by patients in general, and by those with cancer specifically, and details the pharmacological and non-pharmacological strategies that nurses can use to manage this challenging complication.

Use of Nitrous Oxide in Dermatology: A Systematic Review

BACKGROUND

Many dermatologic procedures are painful and can be distressing to patients.

OBJECTIVE

To determine whether nitrous oxide has been used in dermatology and whether literature supports its use in terms of providing analgesia and anxiety associated with dermatologic procedures.

METHODS

A search of PubMed and Cochrane databases was conducted through July 15, 2016, to identify studies involving nitrous oxide use in dermatology.

RESULTS

Eight studies were identified and reviewed. The use of nitrous oxide/oxygen mixture resulted in a significant reduction in pain when used for photodynamic therapy, botulinum toxin therapy for hyperhidrosis of both the palms and axilla, aesthetic procedures involving various laser procedures, and in the treatment of bed sores and leg ulcers. However, pain scores were higher when nitrous oxide/oxygen was used in the debridement of chronic ulcers when compared with the use of topical anesthesia. In addition, nitrous oxide has been reported effective at reducing pain in hair transplants, dermabrasion, excision and repairs, and pediatric procedures.

CONCLUSION

Current literature provides some evidence that nitrous oxide, used alone or as adjunct anesthesia, is effective at providing analgesia for many dermatologic procedures. Nitrous oxide has many potential applications in dermatology; however, further evidence from randomized controlled trials is needed.

A 50-50% mixture of nitrous oxide-oxygen in transrectal ultrasound-guided prostate biopsy: A randomized and prospective clinical trial

Introduction

Transrectal ultrasound-guided biopsy (TUSPB) is the standard method of diagnosis for prostate cancer, and although it is well tolerated by some patients, it presents a discomfort rate of 65 to 90%, which may be associated with pain. For convenience, it is agreed that a method of analgesia and sedation is necessary. For this purpose, this study aimed to evaluate the impact of inhalation of a 50–50% N₂O-O₂ gas mixture on pain intensity in these patients.

Material and methods

Randomized, double-blinded clinical trial, conducted at Antônio Pedro University Hospital (Hospital Universitário Antônio Pedro), Niterói, RJ, Brazil, containing two groups of 42 patients: a control (C) group, which received 100% oxygen inhalation, and a nitrous oxide (NO) group, which received inhalation of the 50–50% N₂O-O₂ mixture, self-administered during TUSPB. The pain intensity and degree of satisfaction were evaluated through a visual analogue scale (VAS), as was the frequency of adverse events.

Results

Eighty-four patients were included in the study, with 42 in each group. The mean pain intensity was lower in the NO group than in the C group [2.52 (0–10) vs 5.95 (0–10), p < 0.001], and the degree of satisfaction was higher in the NO group than in the C group (8.14 vs. 4.69, p < 0.001). The adverse effects were somnolence, dizziness, nausea, vomiting, discomfort and euphoria without differences between the groups.

Conclusion

The 50–50% N₂O-O₂ mixture was effective in reducing pain intensity and increasing the degree of satisfaction in TUSPB, with tolerable side effects.

The effect of nitrous oxide in comparison to oxygen combined with fentanyl on the hospitalization time and pain reduction in renal colic patients at emergency department

Background

Renal colic is a painful medical emergency, needs urgent intervention to reduce pain. Nonsteroidal anti-inflammatory drugs, opioids, and entonox are pain-relieving agents. This study was aimed to compare fentanyl + entonox (nitrous oxide + O₂) versus fentanyl + oxygen.

Materials and Methods

One hundred and twenty patients with acute renal colic presenting to the emergency department were enrolled. First, 50 μg fentanyl was infused for all patients. Then, patients divided into two groups receiving masks of entonox and oxygen, respectively. Quantitative measurement of pain was performed by visual analog scale, before the intervention, after 3, 5, 10, and 30 min of that. If the pain was not relieved after 30 min, 50 μg fentanyl was infused. If the pain was still continued, ketorolac and ketamine were used. Hospitalization duration and severity of pain at specified times were compared between patients in two groups.

Results

The mean (standard deviation) time of hospitalization was 211 (59) and 236 (61) min in fentanyl + entonox and fentanyl + O₂ groups, respectively (P = 0.024). The decrease in pain severity after 10 and 30 min in fentanyl + entonox group were significantly greater than fentanyl + O₂ group (P = 0.002 and 0.001, respectively). Mean (standard error) of needed time for renal colic pain to get better was 11.27 (1.23) and 20.47 (1.71) min in fentanyl + entonox and fentanyl + O₂ groups, respectively (P < 0.001). Proportion of patients relief from pain in fentanyl + entonox in the second, third, and fourth measurements were significantly more than fentanyl + O₂ group (P = 0.036, P < 0.001, and P < 0.001, respectively).

Conclusion

Entonox is more effective to decrease the duration of hospitalization and reduction of pain than O₂ in renal colic patients.

Evaluating the importance of different computed tomography scan-based factors in predicting the outcome of extracorporeal shock wave lithotripsy for renal stones

Purpose

To evaluate the impact of various computed tomography scan-based parameters of renal stones on the outcome of extracorporeal shock wave lithotripsy (ESWL).

Materials and Methods

We conducted a retrospective study of patients who underwent ESWL for renal stones (sized 5–20 mm) from January 2013 to December 2016. We evaluated body mass index, location of the stone, skin-to-stone distance (SSD), stone attenuation value (SAV), stone diameter, Hounsfield density, stone area, and stone volume. Statistical analysis was done and significance was confirmed by multivariate logistic regression analysis.

Results

Of the 203 patients 122 (60.1%) had successful clearance of the stone. The presence of a double J stenting, a lower pole location, a higher SAV, higher Hounsfield density, larger stone area, larger stone diameter, and higher stone volume were negative predictors of ESWL outcome. When these parameters were analyzed with multivariate logistic regression analysis, stone location, SSD, and SAV were the only significant independent predictors of the outcome of ESWL.

Conclusions

Stone location, SSD, and SAV are reliable and strong predictors of ESWL outcome for the treatment of renal stones.

Comparison of Different Analgesia Drug Regimens for Pain Control During Extracorporeal Shock Wave Lithotripsy for Renal Stones: A Randomized Control Study

INTRODUCTION

With the increased use of extracorporeal shock wave lithotripsy (ESWL), the management of urolithiasis has become much convenient for the patients and the health care professionals alike. However, associated with the procedure is the common complaint of pain. No agreed upon pain management strategy has yet been developed for the procedure. We compared the effect of different analgesia drug regiments for pain control.

METHODOLOGY

A randomised controlled trial was carried out in Shifa International Hospital from between July 2015 to January 2016. A total of 135 patients were divided into three groups; group A received 30 g lidocaine 2% gel applied locally on corresponding lumber area 30 minutes before the procedure, group B received oral naproxen sodium 550 mg 45 minutes before the procedure, and group C received both oral naproxen and lidocaine gel. Patients were supplemented with intravenous nalbuphine during the procedure. The pain was assessed with 0-10 visual analogue scale. Both pre-procedure and post-procedure pain score was measured.

RESULTS

Among 135 patients, 105 (77.8%) were male and 29 (21.5%) were female with mean age of 38.7 ± 1.31 years. There was no difference of mean pain score or need for supplemental intravenous nalbuphine between groups B and C but there was significantly decreased mean pain score and need for supplemental intravenous nalbuphine in groups B and C in comparison with group A.

CONCLUSION

The use of oral naproxen sodium with or without the addition of lidocaine gel during ESWL is a promising option for pain management during the procedure with significant improvement in comparison with lidocaine gel alone.

Can percutaneous nephrolithotomy be performed as an outpatient procedure?

Objectives

To examine the safety and effectiveness of percutaneous nephrolithotomy (PCNL) as an outpatient procedure, as in most centres PCNL is performed as an inpatient procedure that necessitates postoperative hospital admission.

Patients and methods

Our study included 186 patients undergoing PCNL for renal calculi. Only those who met strict inclusion criteria were discharged home on the same day. Preoperative eligibility criteria for outpatient management included no complex medical problem, normal renal function, and easy access to an emergency room. Patients were divided into two groups. The outpatient group (Group 1) included those patients discharged on the same day as the PCNL and the hospitalised group (Group 2) included those who were considered appropriate for outpatient management but needed to be hospitalised.

Results

In all, 162 patients (87%) fulfilled the inclusion criteria for outpatient management and 146 of these patients (90.1%) planned for outpatient management were discharged on the same operative day (Group 1). The mean time to discharge home was 8.97 h. In all, 16 patients who opted for the outpatient approach subsequently required hospitalisation (Group 2). In the hospitalised group the mean operative time was longer, which was probably related to its higher stone burden.

Conclusion

PCNL can be safely performed with excellent outcomes as an outpatient procedure. Outpatient PCNL offers several advantages including a more rapid patient convalescence, reduced healthcare expenditure, decreased postoperative nosocomial infections with no additional morbidity for the patient, and with no compromising of the stone-free rate.

Efficacy of preprocedural diclofenac in men undergoing double J stent removal under local anesthesia: A double-blind, randomized control trial

Introduction:

Double J (DJ) stents are often removed under local anesthesia using a rigid cystoscope. Patients experience significant pain during this procedure and also continue to have discomfort during voiding for a few days. We assessed the efficacy and safety of preemptive oral diclofenac in pain relief in patients undergoing DJ stent removal (DJSR) by rigid cystoscopy compared to placebo.

Methods:

Consecutive consenting male patients undergoing DJSR under local anesthesia between March 2014 and July 2015 were enrolled. Patients were randomized to receive 75 mg oral diclofenac (Group A) or placebo (Group B) 1 h before procedure by double-blind randomization. Intraurethral 2% lignocaine gel (25 ml) was used in both groups. Pain during rigid cystoscopy, pain at the first void, and at 24 h after cystoscopy was assessed using visual analog scale (VAS) (0–100). Adverse reactions to diclofenac and episodes of acute urinary retention, if any, were assessed (Trial registered at clinicaltrials.gov: NCT02598102).

Results:

A total of 121 males (Group A [n = 62]; Group B [n = 59]) underwent stent removal. The median (Interquartile range) VAS during the procedure in Group A was 30 (30) and Group B was 60 (30) (P < 0.001), at first void was 30 (30) and 70 (30) (P < 0.001) and at 24 h postoperatively was 20 (20) and 40 (20) (P < 0.001). The incidence of epigastric pain, nausea, vomiting, and acute urinary retention was comparable in the two groups (P > 0.05).

Conclusions:

A single oral dose of diclofenac administered 1 h before DJSR using rigid cystoscope under intraurethral lignocaine anesthesia decreases pain significantly during and up to 24 h postprocedure with minimal side effects.

Maternal Side-Effects of Continuous vs. Intermittent Method of EntonoxDuring Labor: A Randomized Clinical Trial

Labor pain is one of the most tiresome types of pain. So human has been seeking to allay this pain until now. Administration of a suitable agent such as Entonox during labor is very beneficial for childbirth outcomes. Entonox can be administered in two ways: intermittently and continuously. The aim of this study is to demonstrate whether continuous method is as safe as intermittent method? This randomized clinical trial was performed in Mobini Hospital, Sabzevar, Iran. One hundred admitted women for vaginal delivery were included in this study. Fitted patients were randomly divided into two equal groups. After thorough training, the patients used Entonox during active phase of labor. Fifty parturients used it intermittently and 50 others used it continuously. Then, maternal adverse effects, satisfaction and labor progression were registered and compared in two groups. Statistical Analysis was performed by spss17 software, t-test and chi square test. The maternal side effects of Entonox had no significant difference in two groups (p>0.05). Mothers' satisfaction rate in continuous group was more than the intermittent group significantly (p<0.001). Meantime of active phase of labor had no significant difference between two groups (p=0.2). It seems that by more investigations, there will be conditions for mothers to choose the desired method of Entonox usage, intermittently or continuously. This approach leads to reduction of difficult labor and cesarean section and consequently helps improvement of maternal health level, both physically and psychologically.

Care-related pain in hospitalized patients: severity and patient perception of management

BACKGROUND

Hospitalized patients commonly undergo painful procedures, but little is known about care-related pain (CRP) in the overall population of inpatients. We conducted a cross-sectional 1-day survey to assess the prevalence and characteristics of CRP and its management in all units of a university hospital in Paris and determined the factors linked to severe CRP.

METHODS

All patients who were able to communicate and were hospitalized for at least 24 h but not in a day-care or neonatal unit were included.

RESULTS

From 938 patients who completed the questionnaire, 554 patients reported pain within the previous 24 h, for a 59% prevalence of pain, and 540 (58%) had experienced CRP in the previous 15 days (51% males; mean [SD] age 54 [18] years). Of 907 procedures, 330 (37%) resulted in severe pain. The most-often reported painful procedures were vascular punctures and patient mobilization. Severe CRP was associated with long hospitalization; non-vascular invasive punctures, catheterization, mobilization or radiological examination; or pain during the previous 24 h due to surgery or treatment. Only half of the patients declared that they had received information regarding the painful procedure. Treatment for pain was proposed and delivered in less than one quarter of cases.

CONCLUSIONS

Our results of a survey of pain management in hospitalized patients relate to a wide variety of medical conditions and procedures. Health-care workers should be more systematic in managing CRP, and attention should be paid to patients at greatest risk of severe CRP.

Sedative and Analgesic Effects of Entonox Gas Compared with Midazolam and Fentanyl in Synchronized Cardioversion

The purpose of this study was to determine if the Entonox gas could cause adequate analgesic and sedative effects in patients who need cardioversion. In this randomized not blinded clinical trial, the sedative and analgesic effects of midazolam and fentanyl were compared with Entonox. Eligible patients who need synchronized cardioversion because of dysrhythmia were randomly divided into two groups. The first group received intravenous midazolam and fentanyl; the second group received Entonox through a blower-dependent mask. Onset and end of sedation, sedation level, and pain score were recorded. There were nonsignificant differences between the two groups (22 patients in each group) regarding age, gender, weight, sedation level, and frequency and level of shock. The pain score recorded in the first group was 5.05 ± 1.32, and 3.9 ± 0.7 in the second group (P = 0.002). Furthermore, sedation duration and time to full recovery consciousness were shorter in the second group (P < 0.001). In the first group, seven patients needed additional doses to induce and maintain sedation. In addition, as a result of apnoea, four patients required airway support. None of them occurred in the second group. Entonox is a suitable medication in rapid cardioversion, as it has minimal side effects and adequate analgesic and sedative effects.

Analgesic Effects of Inhalation of Nitric Oxide (Entonox) and Parenteral Morphine Sulfate in Patients with Renal Colic; A Randomized Clinical Trial

OBJECTIVE

To compare the analgesiceffects of Nitrous oxide and morphine sulfate in patients with acute renal colic due to urolithiasis.

METHODS

This was randomized clinical trial being performed in Imam Hossein hospital affiliated with Shahid Beheshti University of Medical Sciences during a 1-year period from May2013 to May2014.  A total of number of 100 patients, with an age range of 20-50 years, who presented with renal colic secondary to urolithiasis confirmed by ultrasonography were randomly assigned to receive morphine sulfate injection (0.1 mg/kg) with 100 mg diclofenac suppository (n=50) or Entonox exhalation (50% nitric oxide and 50% oxygen) for 30-minutes with 100 mg diclofenac suppository (n=50). Quantitative measurement was of pain was performed according to a visual analogue scale (VAS), before, 3, 5, 10 and 30-minute after the intervention. The pain severity and side effects were measured between two study groups.

RESULTS

The baseline characteristics of the patients in two study groups were comparable. The frequencies of pain persistence (at least 50%) at 3-, 5-, 10- and 30-minute intervals in morphine sulfategroup were 96%, 80%, 50% and 8%, respectively; these frequencies in Entonex  were 82%, 42%, 12% and 2%, respectively (p<0.001). Cox regression modeling showed that use of Entonox was the only effective agent in the success of treatment, compared to the use of morphine, i.e. use of Entonox increased the success of treatment up to 2.1 folds compared to the use of morphine (HR=2.1; 95% CI: 1.2-3.6; p=0.006).

CONCLUSION

The results of the present study demonstrate that inhalation of Entonox is an effective and safe analgesic regimen for acute renal colic. It acts more rapidly and is more potent in relieving renal colic when compared to morphine sulfate.Entonox can be regarded as an appropriate alternative to analgesics like opioids in this ground.

The perioperative use of nitrous oxide: renaissance of an old gas or funeral of an ancient relict?

PURPOSE OF REVIEW

Conflicting reports about adverse events following nitrous oxide (N(2)O) application have spurred a discussion whether N(2)O should be abandoned from clinical practice. Concurrently, N(2)O is increasingly used as a single anesthetic agent in medical procedures. This article reviews and discusses reports about the present use of N(2)O.

RECENT FINDINGS

Multiple publications demonstrate an increasing use of N(2)O as a procedural analgesic and sedative. Results from the Evaluation of Nitrous Oxide in the Gas Mixture for Anesthesia trial have been contrasted by recent studies reporting no increased risk for perioperative complications, particularly related to the cardiovascular and cerebrovascular system. Recent studies show that electroencephalogram-based anesthesia depth monitoring is not compatible with the use of N(2)O because of its distinct influence on electroencephalogram wave patterns. The clinical relevance of the proposed neurotoxicity, immunosuppression and influence on methionine metabolism remains unclear. Recently, its acute and long-term analgesic potency has been proven. Occupational exposure might pose a relevant health hazard.

SUMMARY

Based on the present literature, abolishment of N(2)O is controversial. When avoided in patients at risk for adverse events, N(2)O is still a valuable supplement to general anesthesia and a potent procedural analgesic drug. In the latter, its use by nonanesthesiologists should be discouraged.

How to improve a urology outpatient service? A survey of patient satisfaction

AIM: To investigate and improve our out-patients department patient satisfaction, provide minimum consultation delay and appropriate consultation duration to meet with targets.

METHODS: We distributed the modified satisfaction with outpatient service (SWOPS) questionnaires developed for use in Irish hospitals by the Health Services Research between August and December 2012. The patient disclosed their age and sex and completed the modified SWOPS questionnaire anonymously. Every patient was eligible to participate in the study who attended any of the Urology Outpatient Clinics. Patients lacking capacity to consent were excluded. Additionally, each patient was only permitted to complete one questionnaire regardless of repeat attendances within the 4 mo study period. The answers to every question were presented as percentages. One-way ANOVA was used to establish whether there was a significant difference in appointment delay and “Overall Satisfaction” on the different clinic days. The unpaired t-test was applied to establish whether “Overall Satisfaction” was affected by diagnosis (benign or malignant). Paired t-test was used to establish whether “Overall Satisfaction” was affected by appointment delay and appointment length.

RESULTS: Three hundred and forty-eight questionnaires were completed with an overall > 65% participation rate. Eighty-one point six percent were male and 18.4% female with a mean age of 65 ± 21 years. Mean delay time was 32 min, which 30.6% stated should be an improvement priority. The delay times for Wednesday (mean 13 min) were significantly (P < 0.05) lower than for other days (mean 36 min). Generally 12-15 min outpatient appointment length is acceptable and adequate for patients as 97.70% suggested, however 31.60% of patients would favour longer duration. Eleven point four nine percent do not want to see different doctors each time, and 31.60% of the patient feel that no change is required. Average satisfaction was 84.65%. There was no significant relationship between satisfaction and clinic day, diagnosis and consultation length, whether the patient was reviewed by a registrar or consultant. Satisfaction was universally high and independent of consultation delay/length and diagnosis. Dissatisfaction in delay times with a significant improvement on Wednesday suggests necessary and achievable improvements. Notably, the Wednesday clinic has less patients per doctor per hour and enforces a 1 patient per 15 min slot with a no over-booking policy.

CONCLUSION: Surveying our patient dissatisfaction would require more frequent audits by clinicians to improve patient satisfaction and to achieve better quality of care.

Renal vascular Doppler resistance after extracorporeal shock wave lithotripsy

OBJECTIVES

Extracorporeal shock wave lithotripsy (ESWL) is mainly an alternative for other therapeutic methods such as surgery and endourology to treat urinary tract calculus. Although it is safe and effective, it has undesirable effects on renal function. Diagnostic techniques such as color Doppler ultrasonography create a new attitude toward renal function. The aim of this study was to evaluate renal vascular resistance change before and after extracorporeal shock wave lithotripsy.

METHODS

During the present study, vascular resistive index (RI) of renal intralobar artery was measured before, 30 min, and 1 week after ESWL using Doppler ultrasonography.

RESULTS

Thirty minutes after ESWL, RI was significantly increased from primary value of 0.62 ± 0.05 to 0.66 ± 0.06 (p = 0.0001). There was no correlation between increase of RI and patients' age. Following up the patients revealed that mean RI did not return to pretreatment level after 1 week (p < 0.05). The RI level in the old patients (3 patients who were 60 years or older) was higher than that of the younger ones (19 patients who were younger than 60 years) after 1 week (0.76 ± 0.05 vs. 0.64 ± 0.06). There was no meaningful relationship between ESWL voltage or number of shocks and RI variation before and after ESWL.

CONCLUSION

Following ESWL, patients are at risk of renal tissue damage due to increase of primary RI level. Measuring RI variations using ultrasound techniques after ESWL may provide helpful information to clinical detection of renal tissue damage.

Applications of nitrous oxide for procedural sedation in the pediatric population

OBJECTIVE

The objective of this review was to provide a general descriptive account of the physical properties, end-organ effects, therapeutic applications, and delivery techniques of nitrous oxide (N2O) as used in the arena of procedural sedation.

DATA SOURCE

A computerized bibliographic search regarding the applications of nitrous for provision of sedation and analgesia during procedures with an emphasis on the pediatric population was performed.

RESULTS

The end-organ effects of N2O have been well described in the operating room setting. Aside from its effects on the central nervous system of sedation and analgesia, N2O may alter intracerebral dynamics and alter cerebral blood flow and intracranial pressure especially in patients with altered intracranial compliance. Effects on ventilation include a dose-related depression of ventilatory function and control of upper airway patency. These effects are generally limited in the absence of comorbid diseases and potentiated by other sedative and analgesic agents. The more clinically significant respiratory effect of N2O on ventilatory function is a dose-dependent depression of the ventilatory response to hypoxemia. Hemodynamic effects include a mild direct depressant effect on myocardial function, which in the absence of comorbid cardiac disease is generally compensated by stimulation of the sympathetic nervous system. Nitrous oxide may potentially aggravate pulmonary hypertension. Additional physiologic effects on neurologic and hematologic function may result in inactivation of the enzyme, methionine synthetase. Recent concern has also been raised regarding the potential effects of N2O on immune function and its relationship to perioperative surgical site infections. Given differences in the solubility, N2O will diffuse into and significantly expand gas-filled cavities. Chronic exposure of health care works to N2O is also a concern. Although there are limited data in the literature to clearly substantiate concerns regarding the reproductive toxicity of occupational exposure to N2O, appropriate scavenging and use of other techniques are mandatory. Nitrous oxide has been shown to be effective for a variety of minor surgical procedures such as venipuncture, intravenous cannula placement, lumbar puncture, bone marrow aspiration, laceration repair, dental care, and minor dermatologic procedures. It is generally as effective as midazolam, with several studies demonstrating it to be more effective. However, its utility is not as great in severely painful procedures such as fracture reduction. Demonstrated advantages to parenteral sedation include a more rapid onset and a shorter recovery time with the majority of patients preferring it to over other agents or agreeing to its use for subsequent procedures. The literature also suggests increased success rates with simple procedures such as intravenous cannula placement when compared with placebo. In general, life-threatening adverse events have not been reported. Most common adverse effects include dysphoria and vomiting. For more painful procedures, combination with another agent may be used, and in all cases, topical or infiltrative local anesthesia is recommended.

CONCLUSIONS

In general, N2O is a useful adjunct for procedural sedation. Given the variety of procedures performed in the pediatric patient, ongoing research is required to identify the most appropriate and effective use of this agent. This may be particularly relevant when evaluating its use for procedures associated with significant pain. In these scenarios, the combination of N2O with other agents needs to be evaluated. Given the potential for adverse effects, strict adherence to published guidelines regarding procedural sedation and monitoring is suggested.