Use of carbon dioxide versus normal saline for diagnostic hysteroscopy

Uterine distension media for outpatient hysteroscopy

BACKGROUND

Hysteroscopy done in an outpatient setting is the 'gold standard' method for evaluating the uterine cavity. Media used to distend the uterine cavity include gas as carbon dioxide and liquid as saline that can be used at room temperature or warmed to body temperature. Both media offer advantages as well as disadvantages.

OBJECTIVES

The objective of this review is to compare the effectiveness, tolerability, and safety of gas (carbon dioxide) and liquid (normal saline) used for uterine distension during outpatient hysteroscopy.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility (CGF) Group Specialised Register, CENTRAL, MEDLINE, Embase and PsycINFO on 28 April 2021. We checked references of relevant trials and contacted study authors and experts in the field to identify additional studies. CINAHL records and ongoing trials from the trial registries were included in the CENTRAL search.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing saline with carbon dioxide, as well as RCTs comparing saline at different temperatures, for uterine distension in outpatient hysteroscopy done for any indication.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. Primary review outcomes were patient tolerability and adverse events or complications related to the distending medium. Secondary outcomes were quality of the hysteroscopic view and duration of the procedure.

MAIN RESULTS

We included 12 RCTs (1946 women). The quality of evidence ranged from very low to high: the main limitations were risk of bias due to absence of blinding due to the nature of the procedure, imprecision, and inconsistency. Saline versus carbon dioxide Analysis ruled out a clinically relevant difference in pain scores during the procedure between saline and carbon dioxide, but the quality of evidence was low (standardised mean difference (SMD) -0.07, 95% confidence interval (CI) -0.17 to 0.02; 9 RCTs, N = 1705; I² = 86%). This translates to differences of 0.39 cm (lower) and 0.05 cm (higher) on a 10-cm visual analogue scale (VAS). Evidence was insufficient to show differences between groups in the proportion of procedures abandoned due to intense pain (Peto odds ratio (OR) 0.48, 95% CI 0.09 to 2.42; 1 RCT, N = 189; very low-quality evidence). We are uncertain whether saline decreases the need for analgesia compared to carbon dioxide (Peto OR 0.34, 95% CI 0.12 to 0.99; 1 RCT, N = 189; very low-quality evidence). Saline compared to carbon dioxide is probably associated with fewer vasovagal reaction events (Peto OR 0.53, 95% CI 0.32 to 0.86; 6 RCTs, N = 1076; I² = 0%; moderate-quality evidence) and fewer shoulder-tip pain events (Peto OR 0.28, 95% CI 0.14 to 0.54; 4 RCTs, N = 623; I² = 0%, moderate-quality evidence). Evidence suggests that if 10% of women undergoing outpatient hysteroscopy experience a vasovagal reaction event with the use of carbon dioxide, this rate would be between 3% and 9% with the use of saline. Similarly, if the rate of shoulder-tip pain with carbon dioxide is 9%, it would be between 1% and 5% with saline. We are uncertain whether saline is similar to carbon dioxide in terms of endometrial bleeding (Peto OR 0.83, 95% CI 0.25 to 2.75; 2 RCTs, N = 349; I² = 0%; very low-quality evidence). Infection was not reported by any study in this comparison. Saline may result in fewer procedures with an unsatisfactory hysteroscopic view than carbon dioxide (Peto OR 0.51, 95% CI 0.32 to 0.82; 5 RCTs, N = 1082; I² = 67%; low-quality evidence). The duration of the procedure was shorter with saline in three of the four studies that reported this outcome, and duration was similar in both arms in the fourth study. Warm saline versus room temperature saline Use of warm saline for uterine distension during office hysteroscopy may reduce pain scores when compared with room temperature saline (mean difference (MD) -1.14, 95% CI -1.55 to -0.73; 3 RCTs, N = 241; I² = 77%; low-quality evidence). Evidence is insufficient to show differences between groups in either the proportion of procedures abandoned due to intense pain (Peto OR 0.97, 95% CI 0.06 to 15.87; 1 RCT, N = 77; very low-quality evidence) or the need for analgesia (Peto OR 1.00, 95% CI 0.14 to 7.32; 1 RCT, N = 100; very low-quality evidence). Analysis ruled out a clinically relevant difference in duration of the procedure between warm and room temperature saline, but the quality of evidence is low (MD 13.17 seconds, 95% CI -12.96 to 39.29; 2 RCTs, N = 141; I² = 21%). No cases of infection were reported in either group (1 RCT, N = 100). No other adverse events and no information on quality of the hysteroscopic view were reported by any study in this comparison.

AUTHORS' CONCLUSIONS

Evidence was insufficient to show differences between different distension media used for uterine distension in outpatient hysteroscopy in terms of patient tolerability, operator satisfaction, or duration of the procedure. However, saline was superior to carbon dioxide in producing fewer adverse events (shoulder-tip pain and vasovagal reaction).

Distending Media Used During Hysteroscopy: Perioperative Nursing Implications

Hysteroscopy is a gynecological procedure that may be indicated for abnormal uterine bleeding, diagnosis and management of infertility, contraception, or sterilization. Surgeons use distending media during hysteroscopy to view the uterine cavity. Media options include carbon dioxide gas and both electrolytic and nonelectrolytic fluids. All distending media is absorbed by the patient's body, but the manner in which each media is absorbed is unique to its chemical composition. Understanding the properties of each distending medium and the risks involved with its use is critical to safe perioperative nursing care for patients undergoing hysteroscopy. This article provides perioperative nurses with a review of uterine anatomy and evidence-based information on the types of distending media used during hysteroscopy and the corresponding perioperative nursing implications.

Complications of Hysteroscopic and Uterine Resectoscopic Surgery

Adverse events associated with hysteroscopic procedures are generally rare, but, with increasing operative complexity, it is now apparent that they are experienced more often. There exists a spectrum of complications that relate to generic components of procedures, such as patient positioning, anesthesia, and analgesia, to a number that are specific to intraluminal endoscopic surgery that largely comprise perforation and injuries to surrounding structures and blood vessels. Whereas a number of endoscopic procedures require the use of distending media, the response of premenopausal women to excessive absorption of nonionic fluids used for hysteroscopy is somewhat unique, and deserves special attention on the part the surgeon. There is also an increasing awareness of uncommon but problematic sequelae related to the use of monopolar radiofrequency uterine resectoscopes that involve thermal injury to the vulva and vagina. Furthermore, the uterus that has previously undergone hysteroscopic surgery may behave in unusual ways, at least in premenopausal women who experience menstruation or who become pregnant. Fortunately, better understanding of the mechanisms involved in these adverse events, as well as the use or development of a number of innovative devices, have collectively provided the opportunity to perform hysteroscopic and resectoscopic surgery in a manner that minimizes risk to the patient.

Humidification during laparoscopic surgery: overview of the clinical benefits of using humidified gas during laparoscopic surgery

PURPOSE

The peritoneum is the serous membrane that covers the abdominal cavity and most of the intra-abdominal organs. It is a very delicate layer highly susceptible to damage and it is not designed to cope with variable conditions such as the dry and cold carbon dioxide (CO2) during laparoscopic surgery. The aim of this review was to evaluate the effects caused by insufflating dry and cold gas into the abdominal cavity after laparoscopic surgery.

METHODS

A literature search using the Pubmed was carried out. Articles identified focused on the key issues of laparoscopy, peritoneum, morphology, pneumoperitoneum, humidity, body temperature, pain, recovery time, post-operative adhesions and lens fogging.

RESULTS

Insufflating dry and cold CO2 into the abdomen causes peritoneal damage, post-operative pain, hypothermia and post-operative adhesions. Using humidified and warm gas prevents pain after surgery. With regard to hypothermia due to desiccation, it can be fully prevented using humidified and warm gas. Results relating to the patient recovery are still controversial.

CONCLUSIONS

The use of humidified and warm insufflation gas offers a significant clinical benefit to the patient, creating a more physiologic peritoneal environment and reducing the post-operative pain and hypothermia. In animal models, although humidified and warm gas reduces post-operative adhesions, humidified gas at 32 °C reduced them even more. It is clear that humidified gas should be used during laparoscopic surgery; however, a question remains unanswered: to achieve even greater clinical benefit to the patient, at what temperature should the humidified gas be when insufflated into the abdomen? More clinical trials should be performed to resolve this query.

Hysteroscopy: guidelines for clinical practice from the French College of Gynaecologists and Obstetricians

The objective of this study was to provide guidelines for clinical practice from the French College of Obstetrics and Gynecology (CNGOF), based on the best evidence available, concerning hysteroscopy. Vaginoscopy should be the standard technique for diagnostic hysteroscopy (Grade A) using a miniature (≤3.5mm sheath) (Grade A) rigid hysteroscope (Grade C), using normal saline solution distension medium (Grade C), without any anaesthesia (conscious sedation should not be routinely used), without cervical preparation (Grade B), without vaginal disinfection and without antibiotic prophylaxy (Grade B). Misoprostol (Grade A), vaginal oestrogens (Grade C), or GnRH agonist routine administration is not recommended before operative hysteroscopy. Before performing hysteroscopy, it is important to purge the air out of the system (Grade A). The uterine cavity distention pressure should be maintained below the mean arterial pressure and below 120mm Hg. The maximum fluid deficit of 2000ml is suggested when using normal saline solution and 1000ml is suggested when using hypotonic solution. When uterine perforation is recognized during operative hysteroscopy using monopolar or bipolar loop, the procedure should be stopped and a laparoscopy should be performed in order to eliminate a bowel injury. Diagnostic or operative hysteroscopy is allowed when an endometrial cancer is suspected (Grade B). Implementation of this guideline should decrease the prevalence of complications related to hysteroscopy.

[Prevention of the complications related to hysteroscopy: guidelines for clinical practice]

OBJECTIVE

To provide clinical practice guidelines (CPGs) from the French college of obstetrics and gynecology (CNGOF), based on the best evidence available, concerning the adverse events related to hysteroscopy.

MATERIALS AND METHODS

Review of literature using following Keywords: hysteroscopy; vaginoscopy; infection; perforation; intrauterine adhesions

RESULTS

Vaginoscopy should be the standard technique for outpatient hysteroscopy (grade A) using a miniature (≤ 3.5mm sheath) (grade A) rigid hysteroscope (grade C), using normal saline solution distension medium (grade C), without any anesthesia (conscious sedation should not be routinely used), without cervical preparation (grade B), without vaginal disinfection and without antibiotic prophylaxy (grade B). Misoprostol (grade A), vaginal estrogens (grade C), or GnRH agonist routine administration is not recommended before operative hysteroscopy. Before performing hysteroscopy, it is important to purge the air out of the system (grade A). The uterine cavity distention pressure should be maintained below the mean arterial pressure and below 120 mmHg. The maximum fluid deficit of 2000 mL is suggested when using normal saline solution and 1000 mL is suggested when using hypotonic solution. When uterine perforation is recognized during operative hysteroscopy using monopolar or bipolar loop, the procedure should be stopped and a laparoscopy should be performed in order to eliminate a bowel injury. Diagnostic or operative hysteroscopy is allowed when an endometrial cancer is suspected (grade B).

CONCLUSION

Implementation of this guideline should decrease the prevalence of complications related to office and operative hysteroscopy.

Hysteroscopy without anesthesia: review of recent literature

The need for anesthesia or analgesia for performing hysteroscopy is still matter of debate. Many factors explain the lack of agreement about anesthesia in hysteroscopy depending on the instrumentation, technique employed, need of performing surgical procedure, operator skill and patients' characteristics. Diagnostic minihysteroscopy (3.5 mm or less in size) is less painful and easier to perform than hysteroscopy performed with instruments sized around 5 mm. Thanks to miniaturized instruments, office hysteroscopy allows a growing number of women to be treated in an office setting avoiding the operating room. The main limitation to its widespread use is pain and low patient tolerance. Intrauterine surgical procedures involving only the endometrial mucosa (biopsies, adhesiolisis, cervical and endometrial polyectomies) are not painful. For endometrial polypectomy size of polyps (<2.2m) and duration of the procedure (more than 15 min) are limiting factors. Most literature suggests that office hysteroscopy in experienced hands is a well-tolerated technique and requires the use of analgesics only in selected patients like women with previous caesarean section, history of chronic pelvic pain, anxiety and in menopause.

Hysteroscopy: a technique for all? Analysis of 5,000 outpatient hysteroscopies

OBJECTIVE

1) To investigate the relationship between operator experience and the success of outpatient hysteroscopy; and 2) to determine if the introduction of normal saline and the use of narrow-caliber hysteroscopes and vaginoscopic approach are associated with a lower failure rate.

DESIGN

Retrospective study.

SETTING

Teaching-hospital based outpatient hysteroscopy clinic.

PATIENT(S)

Five thousand consecutive women undergoing outpatient hysteroscopy between October 1988 and June 2003.

INTERVENTION(S)

The hysteroscopies were carried out both by experienced operators and by trainees. Procedures were performed using 4-mm and 2.9-mm telescopes with 5-mm and 3.5-mm diagnostic sheaths, respectively. Between October 1988 and 1996, the uterine cavity was distended with CO(2) (CO(2) period), whereas normal saline was preferred after 1997 (1997-2003: saline period). Traditional technique of hysteroscope insertion and vaginoscopic approach were used depending on operator preference and experience and patient characteristics.

MAIN OUTCOME MEASURE(S)

Success, failure, and complication rates.

RESULT(S)

The hysteroscopies were successfully performed in nearly 95% of cases by 362 operators (mean 13.8 hysteroscopies per operator) with different levels of expertise. Failure and complication rates were 5.2% and 5.4%, respectively, without any significant difference between CO(2) and saline periods. Vasovagal attacks and shoulder pain were significantly higher during the CO(2) period. The success of outpatient hysteroscopy was negatively affected by postmenopausal status, nulliparity, need for cervical dilatation or local anaesthesia, traditional technique of hysteroscope insertion, and use of a 5-mm hysteroscope.

CONCLUSION(S)

A high level of expertise is not a prerequisite to performing hysteroscopy on an outpatient basis. Recent advances in technique and instrumentation facilitate this approach and might encourage greater adoption by the wider gynecology community.

Efficacy of intravenous tramadol treatment for reducing pain during office diagnostic hysteroscopy

OBJECTIVE

To assess whether IV tramadol before outpatient hysteroscopy could reduce procedure-related pain.

DESIGN

A randomized double-blind placebo controlled trial.

SETTING

Outpatient Hysteroscopy Centre in the Department of Obstetrics and Gynaecology of Cagliari University.

PATIENT(S)

Fifty healthy, parous, women who underwent outpatient diagnostic hysteroscopy and endometrial biopsy.

INTERVENTION(S)

Random IV infusion of tramadol or placebo before hysteroscopy and endometrial biopsy were performed.

MAIN OUTCOME MEASURE(S)

Visual analogue scale of pain was measured both immediately after and 15 minutes after the procedure. Stress hormones (ACTH, cortisol), blood pressure, and heart frequency were evaluated before, during, and 15 minutes after the procedure.

RESULT(S)

In the tramadol group, the visual analogue scale of pain was significantly lower than in the placebo group both immediately after the procedure and 15 minutes later. Basal levels of ACTH and cortisol did not differ between the groups. In both groups, the ACTH levels remained unchanged during the study, and the cortisol levels were higher 15 minutes after the procedure than before the procedure. Procedure time, heart frequency, blood pressure, and adverse effects did not differ between the groups.

CONCLUSION(S)

In parous women without uterine malformations, a treatment with tramadol before hysteroscopy and endometrial biopsy appears to be capable of reducing the pain and discomfort that are associated with this procedure.

Vaginoscopic versus conventional approaches to outpatient diagnostic hysteroscopy: a two-centre randomized prospective study

BACKGROUND

To compare the tolerability and feasibility of the transvaginal and standard approaches in outpatient diagnostic hysteroscopy.

METHODS

This randomized prospective trial was carried out in two centres to compare the transvaginal (n = 200) and conventional (n = 200) approaches during outpatient hysteroscopy. Patients were randomized by a computer-generated list. The main outcome measure was pain during the examination, measured on a visual analogue scale (VAS) graded from 0 to 10 (0 = lowest, 10 = highest). Secondary criteria were ease of instrument passage through the cervix, investigation quality and its duration. For data analysis, we used the chi-squared test or Fischer's exact test for qualitative variables and the Mann-Whitney U-test for quantitative variables.

RESULTS

Median VAS was rated at 0.5 for the vaginoscopic and 2 for the standard (P < 0.0001) approaches. The approaches did not differ significantly in investigation quality, procedure duration or ease of cervical passage (although the latter was more often easy transvaginally).

CONCLUSIONS

The transvaginal approach is better tolerated than the conventional technique in outpatient diagnostic hysteroscopy.

Hysteroscopy and Ultrasonography in the Diagnosis of Endometrial Cancer

The main aim of investigating women with abnormal uterine bleeding is to exclude serious intrauterine pathology, particularly endometrial cancer. Endometrial assessment has traditionally been achieved by obtaining tissue for histological analysis utilising blind in-patient dilatation of the cervix and curettage of the endometrium under general anaesthesia. This procedure is now generally accepted as outmoded practice associated with unnecessary morbidity and cost and has been largely replaced by minimally invasive out-patient or 'ambulatory' diagnostic modalities. These modalities include transvaginal ultrasonography, out-patient hysteroscopy and miniature endometrial biopsy. The most controversial debate has centred on how best to image the uterine cavity with advocates of hysteroscopy and ultrasonography holding apparently implacable views. However, the concept of hysteroscopy and ultrasonography as competing tests may be misplaced, and perhaps they should be viewed as complementary diagnostic tools. To help us answer such questions requires an appraisal of the available evidence. In this way, a more rational approach to investigating women for endometrial cancer is possible based on the clinical and economic performance of hysteroscopy and ultrasonography. This review assesses the evidence and suggests approaches available to gynaecologists for the diagnostic work-up of women suspected to have endometrial cancer utilising hysteroscopy and ultrasonography.

General gynaecology: Intrauterine lignocaine as an anaesthetic during endometrial sampling: a randomised double-blind controlled trial

OBJECTIVE

To evaluate the effectiveness of intrauterine lignocaine as an anaesthetic during endometrial sampling.

DESIGN

Prospective, randomised, double-blind, placebo-controlled trial.

SETTING

Outpatient gynaecological minor operation unit in a public hospital.

POPULATION

Two hundred premenopausal women scheduled for endometrial sampling because of abnormal uterine bleeding.

METHODS

Transcervical intrauterine instillation of 5 mL of 2% lignocaine or 5 mL of normal saline before performing endometrial sampling with vacuum aspirator.

MAIN OUTCOME MEASURES

Evaluation of pain associated with the procedure using a visual analogue scale.

RESULTS

The use of intrauterine lignocaine reduced pain during suction curettage in endometrial sampling.

CONCLUSIONS

Transcervical instillation of lignocaine reduced pain during endometrial sampling.

Selecting distending medium for out-patient hysteroscopy. Does it really matter?

BACKGROUND

The aim of this prospective randomized study was to evaluate the role of carbon dioxide (CO2) and normal saline for diagnostic accuracy in out-patient hysteroscopy.

METHODS

Women admitted to our Department in order to undergo total abdominal hysterectomy also underwent diagnostic hysteroscopy, 12-24 h prior to surgery. The selection of distending medium was made after randomization. Two groups of patients were formed, group A (CO2; n=39) and group B (normal saline; n=35). More than half of the women in the study population were post-menopausal. Post-hysteroscopy, all women were asked to rank any symptom that they felt during the procedure on a 4-point scale (0=none; 1=mild; 2=severe; 3=inability to perform hysteroscopy). The hysteroscopic diagnosis was compared with the macroscopic findings and the histological examination of the surgical specimen after hysterectomy.

RESULTS

The percentage who completed hysteroscopy was 89.74% within group A and 97.14% within group B. Most patients of both groups felt some pain of mild intensity. The diagnostic accuracy of hysteroscopy was similar for both media when major pathology [large polyps (group A 91.7%; group B 92.7%), myomas (group A 81.25%; group B 92.7%) and/or hyperplasia (group A 87.5%; group B 90.2%)] of the endometrial cavity was detected. In contrast, in cases of minor pathology (small polyps, mucosal elevations, crypts, hypervascularization), hysteroscopy with saline presented with significantly higher diagnostic accuracy (85.4%) compared with hysteroscopy with CO2 (64.6%).

CONCLUSIONS

In out-patient hysteroscopy, CO2 and normal saline were comparable with regard to patient discomfort and for the detection of major pathology of the endometrial cavity. Normal saline seems to be the most appropriate medium for the detection of minor pathology of the endometrial cavity.

Outpatient hysteroscopy and ultrasonography in the management of endometrial disease

PURPOSE OF REVIEW

This review is to inform the ongoing debate about the choice between ultrasound and hysteroscopy in the management of endometrial disease presenting with abnormal uterine bleeding using information provided from recently published literature.

RECENT FINDINGS

Transvaginal ultrasound measurement of endometrial thickness, using 4 or 5 mm cut-offs to define abnormality, is a good test for excluding endometrial cancer in women with postmenopausal bleeding. In contrast, hysteroscopy is a good test for detecting endometrial cancer, but less effective at excluding serious disease. The accuracy of transvaginal ultrasound in diagnosing intracavity pathology such as submucous fibroids and polyps is improved with saline instillation to levels of accuracy comparable to that of outpatient hysteroscopy. Miniaturization of hysteroscopes and ancillary instrumentation (e.g. development of bipolar intrauterine systems) has facilitated 'see and treat' outpatient hysteroscopy, so that it should no longer be considered simply an outpatient diagnostic modality. Preliminary cost-effectiveness studies have supported the use of ultrasound in the diagnosis of endometrial disease, but further, more comprehensive studies are required comparing ultrasound and outpatient hysteroscopy.

SUMMARY

Recently published research has provided the clinician with high-quality data regarding the accuracy of ultrasound and hysteroscopy in the diagnosis of endometrial disease. Despite this, controversy remains regarding the relative roles of these uterine imaging modalities. Future research needs to be directed towards providing effectiveness and cost-effectiveness data in order to resolve the ongoing debate and guide best clinical practice.