Pain control in first trimester surgical abortion: Cochrane systematic review
Assessed as up to date: 2007/12/24
First trimester abortions especially cervical dilation and suction aspiration are associated with pain, despite various methods of pain control.Objectives
Compare different methods of pain control during first trimester surgical abortion.Search strategy
We searched multiple electronic databases with the appropriate key words, as well as reference lists of articles, and contacted professionals to seek other trials.Selection criteria
Randomized controlled trials comparing methods of pain control in first trimester surgical abortion at less than 14 weeks gestational age using electric or manual suction aspiration. Outcomes included intra- and postoperative pain, side effects, recovery measures and satisfaction.Data collection and analysis
Two reviewers independently extracted data. Meta-analysis results are expressed as weighted mean difference (WMD) or Peto Odds ratio with 95% confidence interval (CI).Main results
We included forty studies with 5131 participants. Due to heterogeneity we divided studies into 7 groups:
Local anesthesia: Data was insufficient to show a clear benefit of a paracervical block (PCB) compared to no PCB or a PCB with bacteriostatic saline. Pain scores during dilation and aspiration were improved with deep injection (WMD -1.64 95% CI -3.21 to -0.08; WMD 1.00 95% CI 1.09 to 0.91), and with adding a 4% intrauterine lidocaine infusion (WMD -2.0 95% CI -3.29 to -0.71, WMD -2.8 95% CI -3.95 to -1.65 with dilation and aspiration respectively).
PCB with premedication: Ibuprofen and naproxen resulted in small reduction of intra- and post-operative pain.
Analgesia: Diclofenac-sodium did not reduce pain.
Conscious sedation: The addition of conscious intravenous sedation using diazepam and fentanyl to PCB decreased procedural pain.
General anesthesia (GA): Conscious sedation increased intraoperative but decreased postoperative pain compared to GA (Peto OR 14.77 95% CI 4.91 to 44.38, and Peto OR 7.47 95% CI 2.2 to 25.36 for dilation and aspiration respectively, and WMD 1.00 95% CI 1.77 to 0.23 postoperatively). Inhalation anesthetics are associated with increased blood loss (p<0.001).
GA with premedication: The COX 2 inhibitor etoricoxib, the non-selective COX inhibitors lornoxicam, diclofenac and ketorolac IM, and the opioid nalbuphine were improved postoperative pain.
Non-pharmacological intervention: Listening to music decreased procedural pain.
No major complication was observed.Authors' conclusions
Conscious sedation, GA and some non-pharmacological interventions decreased procedural and postoperative pain, while being safe and satisfactory to patients. Data on the widely used PCB is inadequate to support its use, and it needs to be further studied to determine any benefit.
Renner Regina-Maria, Jensen Jeffrey T.J., Nichols Mark D.N., Edelman Alison
Pain control in first trimester surgical abortion.
Multiple methods of pain control in first trimester surgical abortion at less than 14 weeks gestational age using electric or manual suction aspiration are available, and appear both safe and effective. Pain control methods can be divided in local anesthesia, conscious sedation, general anesthesia and non-pharmacological methods. Data to support the benefit of the widely used local aneathetic is inadequate. While general anesthesia achieved complete pain control during the procedure, other forms of anesthesia such as conscious sedation with a paracervical block improved postoperative pain control.
Implications for practice
Methods of pain control including local anesthesia, IV sedation, general anesthesia and non-pharmacological methods for first trimester surgical abortion have been studied. Many have been found to effectively decrease pain during and after the procedure while being safe and satisfactory to patients. No major complications were observed in any study. Many patients still find the procedure extremely uncomfortable due to pain with cervical dilation and aspiration, unless given general anesthesia. Given how widely used the PCB is, the paucity of data supporting the benefit of a PCB as shown in this review is surprising and concerning.
Given these findings, factors such as women’s preference, medical risk factors for anesthesia complications, setting and resources availability should be considered when choosing a method of pain control. Trials were too heterogeneous to be combined in a large meta-analysis.
Considering the small WMD of some significant results, as well as the quality of evidence the strongest evidence supports:
1) Data on the effect of a PCB and buffered lidocaine are conflicting. PCB with local anesthetic such chloroprocaine reduced pain with PCB injection, cervical dilation and aspiration in only one small study, and only when injected at 4 sites, but not when injected at only 2 sites. Another study did not show any benefit of a PCB over no PCB. A deep injection technique seems to reduce pain with cervical dilation and aspiration. Strong evidence supports adding intrauterine 4% lidocaine, but one must be prepared for patients reporting lidocaine exposure sumptoms (i.e. ear ringing).
2) Conscious sedation combined with PCB do not achieve the same pain control as general anesthesia during the procedure, but improved postoperative pain control.
3) General anesthesia ideally consists of a combination of propofol (methohexital, etomidate and thiopentane had very similar results, but have fallen out of favour in many places by now for procedural pain control) with an opioid for postoperative pain control.
4) Premedication for general anesthesia: lornoxicam, IM ketorolac or diclofenac.
Implications for research
Future studies should aim for using the same outcomes and study instruments to measure pain in order to increase comparability. In order to establish as to whether the PCB is effective of not, a well designed and large study is needed, comparing PCB to a no treatment arm rather than comparing it to placebo, given that the injection of the PCB itself is painful. More studies should try to compare local anesthesia with conscious sedation and general anesthesia regarding pain during and after the procedure as well as regarding side effects, time until discharge, and satisfaction. The nature of general anesthesia, which achieves complete pain control during the surgery, challenges direct comparison to any other form of anesthesia.
Newer observational data on risks of general anesthesia will further help to improve its adequate risk perception. Such data may revise current recommendations.Get full text at The Cochrane Library
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