The effect of cervical dilatation by laminaria on the plasma levels of 15-keto-13,14-dihydro-PGF2 alpha

Opioid prescription for pain after osmotic dilator placement in abortion care: A randomized controlled trial

OBJECTIVE

To compare the overnight maximum pain scores after osmotic dilator placement prior to a dilation and evacuation (D&E) procedure in participants assigned to a prescription for ibuprofen alone or to ibuprofen plus oxycodone.

STUDY DESIGN

We conducted a nonblinded pragmatic, randomized controlled trial to evaluate pain management among women undergoing osmotic dilator placement prior to D&E. We randomly assigned 70 participants at 12 weeks 6 days to 23 weeks 6 days gestation to receive a prescription for ibuprofen alone, or ibuprofen plus oxycodone. We assessed pain using a numeric rating scale (NRS; scale 0-10) at the following time points: Baseline, dilator placement, 2 and 6 hours, and preoperatively, where we also asked participants their maximum pain score. The primary outcome was mean individual NRS pain score change from baseline to maximum pain score.

RESULTS

Maximum mean pain score (change from baseline) was 4.7 ± 2.9 in the ibuprofen group, and 6.5 ± 2.5 in the ibuprofen plus oxycodone group (p < 0.01). Participants in both groups reported highest NRS pain scores 2 hours after dilator placement, 3.9 ± 2.5 and 5.3 ± 2.6 respectively (p = 0.02). Average ibuprofen use in both arms was similar, and 81% of participants used at least 1 dose of ibuprofen after dilator placement. Of those randomized to prescription to ibuprofen plus oxycodone, only 51% used a dose of oxycodone.

CONCLUSIONS

Compared to participants randomized to receive a prescription for ibuprofen, those randomized to receive a prescription for ibuprofen plus oxycodone reported higher maximum overnight pain scores.

IMPLICATIONS

Participants receiving a prescription for ibuprofen alone had lower maximum overnight pain scores following osmotic dilator placement. Given that opioid prescriptions did not appear to reduce overnight pain, minimizing these prescriptions would avoid opioid exposure for patients undergoing D&E.

Sublingual misoprostol plus laminaria for cervical preparation before surgical management of late first trimester missed abortions, a randomized controlled trial

OBJECTIVE

Comparing the efficacy of low-dose sublingual misoprostol plus laminaria to medium-dose sublingual misoprostol alone for cervical dilation before surgical management of late first trimester missed abortions.

METHODS

Randomized, controlled trial evaluated 70 women with missed abortion, admitted for surgical termination of pregnancy. The patients were randomly assigned to receive 200 μg sublingual misoprostol with cervical laminaria (intervention group) or 400 μg sublingual misoprostol without laminaria (control group), four hours before surgical process. The study is registered at www.irct.ir (IRCT2014070711020N4).

RESULTS

More patients in the intervention group achieved the desired cervical dilation (≥Hegar7) before surgical process than the control group (91.4% versus 17.1%, p < 0.001). Patients in the intervention group experienced less pain during the waiting period (mean Visual Analog Scale scores: 30.8 ± 3.7 versus 43.7 ± 5.9, p < 0.001), and had higher satisfaction level (highly satisfied: 97.1% versus 77.1%, p = 0.02). Four patients in the intervention group and none in the control group had spontaneous expulsion of pregnancy products (p = 0.11).

CONCLUSIONS

Compared to medium-dose sublingual misoprostol alone, using a combination of cervical laminaria plus low-dose sublingual misoprostol before surgical process is associated with significantly more effective and rapid cervical dilation, lower requirement for mechanical dilation, lower abdominal pain and discomfort during the waiting period and higher patients' satisfaction.

Cervical dilation before first-trimester surgical abortion (<14 weeks' gestation)

First-trimester surgical abortion is a common, safe procedure with a major complication rate of less than 1%. Cervical dilation before suction abortion is usually accomplished using tapered mechanical dilators. Risk factors for major complications in the first trimester include increasing gestational age and provider inexperience. Cervical priming before first-trimester surgical abortion has been studied using osmotic dilators and pharmacologic agents, most commonly misoprostol. Extensive data demonstrate that a variety of agents are safe and effective at causing preoperative cervical softening and dilation; however, given the small absolute risk of complications, the benefit of routine use of misoprostol or osmotic dilators in first-trimester surgical abortion is unclear. Although cervical priming results in reduced abortion time and improved provider ease, it requires a delay of at least 1 to 3 h and may confer side effects. The Society of Family Planning does not recommend routine cervical priming for first-trimester suction abortion but recommends limiting consideration of cervical priming for women at increased risk of complications from cervical dilation, including those late in the first trimester, adolescents and women in whom cervical dilation is expected to be challenging.

Cervical dilation before first-trimester surgical abortion (<14 weeks' gestation). SFP Guideline 20071

First-trimester surgical abortion is a common, safe procedure with a major complication rate of less than 1%. Cervical dilation before suction aspiration is usually accomplished using tapered mechanical dilators. Risk factors for major complications in the first trimester are increasing gestational age and provider inexperience. Use of laminaria for cervical priming reduces the risk of cervical laceration and, to a lesser extent, uterine perforation. While pharmacological priming agents may potentially have the same effects, no published studies to date have been large enough to assess these outcomes. Given an experienced provider, the risk of these injuries during suction aspiration is very small. Cervical priming can be achieved with osmotic dilators or pharmacological agents. The advantages of osmotic dilators such as laminaria, Dilapan-S and Lamicel are their ability to produce wide cervical dilation, and for the synthetic types, their advantages include predictable effects and rapid onset of action. A disadvantage of osmotic dilators is that they require a speculum examination and a trained clinician to perform the insertion. When cervical priming is performed, misoprostol is the prostaglandin analogue most commonly used worldwide. Compared to laminaria, vaginal misoprostol requires a shorter period of time to achieve the same dilatation, is associated with less discomfort and is preferred by women. The sublingual route appears as effective as vaginal administration and requires less time for priming (2 h), but it is associated with more side effects. Oral administration can produce equivalent dilation to vaginal or sublingual administration, but higher doses and longer treatment periods (8 to 12 h) are required. Buccal administration of misoprostol appears to have a pharmacokinetic and physiologic profile similar to vaginal administration; however, there are no published studies of buccal misoprostol prior to first-trimester suction abortion. While extensive data demonstrate that a variety of agents are safe and effective at causing cervical softening and dilation preoperatively, there are not enough data to conclude that routine cervical priming is necessary to reduce complications of first-trimester surgical abortion. Cervical priming increases preoperative cervical dilation, making the procedure easier and quicker for the physician. However, in order to preoperatively dilate the cervix, the woman must receive the agent at least 3 to 4 h prior to her procedure. Besides the additional waiting, the woman might experience bleeding and cramping prior to the procedure. There are insufficient data evaluating how cervical priming affects women's quality of life in relation to abortion. Based on existing evidence, the Society of Family Planning does not recommend routine cervical priming for suction aspiration procedures. The Society of Family Planning further recommends that providers consider cervical priming only for women who may be at increased risk of complications from cervical dilation, including those late in the first trimester, adolescents and women in whom cervical dilation is expected to be difficult due to either patient factors or provider experience.

Complications of osmotic dilators

This article reviews safety, efficacy, and complications of intracervical osmotic devices and discusses diagnostic, therapeutic, and preventative measures for managing them. Osmotic dilators have been used to ripen the cervix in gynecologic and obstetric procedures for centuries. Their gradual effect in softening and dilating the cervix reduces the chance of stretch injury or perforation and could enhance completeness of evacuation of the uterine cavity. Natural and synthetic devices are available, each with unique properties. Notwithstanding major advances in prostaglandin analogs as cervical ripeners, these mechanical devices continue to play a vital role in cervical preparation. In the event of an unfavorable cervix, they are adjuncts for accelerating inductions of labor and for safe uterine entry during hysteroscopy and diagnostic dilation and curettage. For inducing pregnancy, they are routinely used as cervical ripeners from the late first trimester onward. The English-language literature was surveyed. The author used citations from a MEDLINE search, 2 unpublished case reports, and personal experience. Laminaria and Dilapan dilators can get trapped and fragment with the potential for serious adverse clinical and legal consequences. Lamicel devices do not share this feature. Serious infection is uncommon and anaphylaxis is rare. Timely, well-selected imaging techniques can aid diagnosis. Preventative measures could reduce the number and severity of osmotic dilator-associated complications. Measures suggested by some include predilating with metal dilators, incorporating laminaria or Lamicel devices with Dilapan, adding misoprostol, and using sonohysterography. However, these measures, singly and in combination, are unlikely to eliminate all complications.

Prostaglandin release from human cervical tissue in the first trimester of pregnancy after preoperative dilatation with hygroscopic tents

Preoperative dilatation with hygroscopic tents before first trimester abortion by vacuum aspiration is widely accepted and reduces the risk of early and late complications. A softening effect and a reduced compliance to mechanical dilatation occurs in addition to pure mechanical dilatation of the cervix. If this softening is an effect of local prostaglandin release, however, is unknown. Prostaglandin (PG) release in vitro from cervical biopsies following dilatation in vivo by a synthetic hygroscopic tent (Dilapan) for periods of 4 h and 18 h was compared with that of biopsies from untreated women. No difference was observed between the release of PGE2, PGF2 alpha, or 6-keto-PGF1 alpha. No significant difference was found in the tissue water content between treated and untreated women (83.8% versus 83.2%). Prostaglandins were also extracted from an alternative cervical dilator, Lamicel (a polyvinyl sponge impregnated with magnesium sulfate), and compared with the corresponding values from women pretreated with the cyclooxygenase inhibitor indomethacin before application of the tent. Significantly higher concentrations of PGE2 and PGF2 alpha but not of 6-keto-PGF1 alpha were found in women who had not been indomethacin-treated compared with indomethacin-treated women. Slices of the cervix from non-pregnant women operated upon for benign conditions were divided into an outer stromal layer and an inner layer, including the mucosa, and the PG-release in vitro was measured. The inner layer of the cervix showed a significantly higher release of PGE2 and PGF2 alpha compared with the outer layer. Lamicel treatment before first trimester abortion results in a significant dilatation of the cervix and a reduced compliance to mechanical dilatation, and this study supports the hypothesis that this effect is mediated via a local PG-release from the cervix. It seems reasonable to believe that Dilapan treatment too has the capacity to induce PG-release from the cervix, but this could not be demonstrated in this study, probably because needle biopsies taken mainly from the outer cervical layers were analyzed.

Effect of predilatation of the uterine cervix by laminaria tent on activity of the placenta

Serum concentrations of hCG were determined in blood samples taken 18-20 h and immediately before vacuum aspiration in 45 women in gestational weeks 7-9, admitted for legal abortion. In 35 of the women, a laminaria tent was inserted for cervical dilatation immediately after the first blood sampling. Serum hCG values decreased significantly in the women pretreated with laminaria tent, but were unchanged in the untreated women. This finding may indicate that pretreatment with a laminaria tent induces a partial placental detachment.

The effect of cervical dilatation by laminaria tent in first trimester legal abortions on blood loss related to fibrinolytic activity in the decidua and placenta

Increased blood loss (BL) has been reported after cervical dilatation by laminaria tent in legal abortions. The BL was measured in 72 women in whom first trimester legal vacuum aspiration was performed. The cervical canal was dilatated by laminaria tent in 37 patients, and mechanically with Hegar dilators in 35 patients. BL was studied in relation to the plasminogen activators (u-PA, t-PA) and the plasminogen activator inhibitors (PAI-1, PAI-2) in the decidua and placenta. There was no significant difference in BL between the two groups. Decidual PAI-1 concentrations were significantly higher in the laminaria tent group than in the Hegar dilator group. An inactivation of u-PA by PAI-1 might explain the lack of increase in BL among the laminaria tent group.

Biochemical changes in human cervical connective tissue during pretreatment with laminaria tents in legal first trimester abortions

In 14 legal first trimester abortions, vacuum aspiration was preceded by dilatation of the cervical canal by laminaria tent for 16-20 h. Biopsy specimens obtained from the cervix before insertion and before removal of the laminaria tent were analyzed for biochemical changes in cervical connective tissue. Pretreatment with laminaria tents resulted in a decrease of the total collagen concentration and of the collagenolytic activity, though the differences were without statistical significance. Both these findings and those concerning the subfractions of the hydroxyproline concentration suggest that pretreatment with laminaria induces a certain degree of softening of the cervix, similar to that reported after intracervical application of PGE2 gel.

Contractile activity in the human uterine cervix and corpus during cervical dilatation by laminaria tent in first trimester legal abortions

Millar microtransducers were used in 7 patients to record contractile variations in the cervix and corpus during dilatation of the cervical canal by Laminaria tent preceding first-trimester vacuum aspiration. The spontaneous contractile activity was registered in a control group of 5 patients without laminaria pretreatment. Two Millar catheters were used. The sensor tip of one Millar catheter was placed extra-amniotically in the uterine cavity, and the other one in the mid-cervical canal. Both sensor tips faced the wall of the cervix and corpus. The study showed that laminaria tents not only have a gentle dilatating effect on the cervix, but also induce painless uterine contractions, of amplitudes reaching 20 mmHg, and increased contractile activity in the cervix for the duration of dilatation.