Anaesthesia for short outpatient procedures. A comparison between thiopentone and propofol in combination with fentanyl or alfentanil

Local anaesthesia for pain control in first trimester surgical abortion

BACKGROUND

Abortions prior to 14 weeks are among the most common outpatient surgical procedures performed on people capable of becoming pregnant. Various methods have been used to control pain; however, many people still experience pain with the procedure.

OBJECTIVES

To evaluate the benefits and harms of local anaesthesia given for pain control during surgical abortion at less than 14 weeks' gestation.

SEARCH METHODS

We searched CENTRAL (Ovid EBM Reviews), MEDLINE (Ovid), Embase, POPLINE, and Google Scholar to December 2022 for randomized controlled trials of pain control in surgical abortion at less than 14 weeks' gestation using suction aspiration. We searched the reference lists of related reviews and articles.

SELECTION CRITERIA

We selected effectiveness and comparative effectiveness randomized controlled trials that studied local anaesthesia with common local anaesthetics and administration routes given for pain control in surgical abortion at less than 14 weeks' gestation using uterine aspiration. Outcomes included intraoperative pain, patient satisfaction, and adverse events.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We computed mean differences (MD) with 95% confidence intervals (CI) for continuous variables reporting a mean. We assessed the certainty of evidence using GRADE.

MAIN RESULTS

Thirteen studies with 1992 participants met the inclusion criteria. Due to heterogeneity of interventions, we could not pool more than two studies for any outcome. We used 13 mm improvement on a visual/verbal analogue scale to indicate a clinically meaningful difference in pain with surgical abortion (pain with dilation, aspiration, or during procedure). Based on type of pain control, we divided studies into three groups. Paracervical block (PCB) effectiveness trials A 20 mL 1% lidocaine PCB reduced pain with dilation (MD -37.00, 95% CI -45.64 to -28.36), and aspiration (MD -26.00, 95% CI -33.48 to -18.52) compared to a sham PCB (1 RCT, 120 participants; high-certainty evidence). A PCB with 14 mL of 1% chloroprocaine resulted in a slight reduction in pain with aspiration compared to a PCB with normal saline injected at two or four sites (MD -1.50, 95% CI -2.45 to -0.55; 1 RCT, 79 participants; high-certainty evidence). PCB comparative effectiveness trials An ultracaine PCB probably results in little to no clinically meaningful difference in pain during procedure compared to topical cervical lidocaine spray (median 1 point higher, interquartile range (IQR) 0 to 3; P < 0.001; 1 RCT, 48 participants; moderate-certainty evidence). A 1000 mg dose of intravenous paracetamol probably does not decrease pain as much as ultracaine PCB during procedure (median 2 points higher, IQR 1 to 3; P < 0.001; 1 RCT, 46 participants; moderate-certainty evidence). Various local anaesthetics in PCB comparative effectiveness trials A 10 mL buffered 2% lidocaine PCB probably does not result in a clinically meaningful difference in pain with dilation compared to a plain lidocaine PCB (MD -0.80, 95% CI -0.89 to -0.71; 1 RCT, 167 participants; moderate-certainty evidence). A buffered lidocaine PCB probably does not result in a clinically meaningful difference in pain with aspiration compared to plain lidocaine PCB (MD -0.57, 95% CI -1.01 to -0.06; 2 RCTs, 291 participants; moderate-certainty evidence). Non-PCB local anaesthesia or PCB technique effectiveness trials PCB: waiting versus no waiting Waiting three to five minutes between 1% lidocaine PCB injection and dilation probably does not result in a clinically meaningful difference in pain with dilation compared to not waiting (MD -0.70, 95% CI -1.23 to -0.17; 2 RCTs, 357 participants; moderate-certainty evidence). Topical cervical analgesia Topical 10 mL 2% lignocaine gel probably does not result in a clinically meaningful difference in pain with aspiration compared to KY Jelly (MD -0.87, 95% CI -1.60 to -0.14; 1 RCT, 131 participants; moderate-certainty evidence). In participants who also received a PCB, 20 mg topical cervical lidocaine spray probably does not result in a clinically meaningful difference in pain during the procedure compared to two pumps of normal saline spray (median -1 point, IQR -2 to -1; P < 0.001; 1 RCT, 55 participants; moderate-certainty evidence). Intravenous paracetamol 1000 mg compared to two pumps of cervical lidocaine spray probably does not results in a clinically meaningful difference in pain procedure (median 1 point, IQR -2 to 2; P < 0.001; 1 RCT, 48 participants; low-certainty evidence). Non-PCB local anaesthesia or PCB technique comparative effectiveness trials Depth of PCB The evidence suggests that a 3-cm deep PCB probably does not result in a clinically meaningful difference in pain with aspiration compared to a 1.5-cm deep PCB (MD -1.00, 95% CI -1.09 to -0.91; 2 RCTs, 229 participants; low-certainty evidence). PCB: four sites versus two sites A two-site (4-8 o'clock) 20 mL 1% lidocaine PCB does not result in a clinically meaningful difference in pain with dilation compared to a four-site (2-4-8-10 o'clock) PCB (MD 8.60, 95% CI 0.69 to 16.51; 1 RCT, 163 participants; high-certainty evidence). Overall, participants reported moderately high satisfaction with pain control and studies reported few adverse events.

AUTHORS' CONCLUSIONS

Evidence from this updated review indicates that a 20 mL 1% plain lidocaine PCB decreases pain during an abortion procedure. Evidence supports forgoing buffering lidocaine and a wait time between PCB injection and cervical dilation. A 1.5-cm deep injection as opposed to a 3-cm deep injection is sufficient. A two-site PCB injection as opposed to a four-site injection has similar effectiveness. Topical cervical anaesthesia (10 mL 2% lignocaine gel or 20 mg topical cervical lidocaine spray) as compared to placebo did not decrease pain based on moderate-certainty evidence, but then when compared to PCB, pain control was similar. Due to this inconsistency in evidence regarding the effectiveness of topical anaesthesia, its routine use is presently not supported. This review did not include studies of pain management with conscious sedation but, based on the results of our prior Cochrane review and the 2022 WHO guidelines, we recommend that the option of combination of pain management using conscious sedation plus PCB and non-steroidal anti-inflammatory drugs should be offered where conscious sedation is available as it further decreases pain.

Pain control in first trimester surgical abortion

BACKGROUND

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.

The use of peripheral nerve blocks at the elbow for carpal tunnel release

This case report illustrates that median, radial, and ulnar nerve blocks at the elbow provides anesthesia for ambulatory carpal tunnel release surgery. This report discusses 3 patients with medical conditions, including vascular access problems and morbid obesity, which made nerve blocks at the elbow advantageous compared with other anesthetic techniques. Peripheral nerve blocks at the elbow were done before surgery in a block room, so the patients spent less time in the operating room. Nerve blocks at the elbow are effective anesthesia for hand procedures with no patient requiring further local anesthetic injection and opioids for pain or expressing any discomfort during surgery. The blocks are easy to perform and set up quickly, and using long-acting local anesthetics, elbow blocks provide postoperative pain control for approximately 10 hours. The nerve blocks at the elbow facilitate the perioperative process by being done out of the operating room and providing prolonged pain control without the need for opioids, so nausea may be avoided.

Comparative effect of intraoperative propacetamol versus placebo on morphine consumption after elective reduction mammoplasty under remifentanil-based anesthesia: a randomized control trial [ISRCTN71723173]

Background

Postoperative administration of paracetamol or its prodrug propacetamol has been shown to decrease pain with a morphine sparing effect. However, the effect of propacetamol administered intra-operatively on post-operative pain and early postoperative morphine consumption has not been clearly evaluated. In order to evaluate the effectiveness of analgesic protocols in the management of post-operative pain, a standardized anesthesia protocol without long-acting opioids is crucial. Thus, for ethical reasons, the surgical procedure under general anesthesia with remifentanil as the only intraoperative analgesic must be associated with a moderate predictable postoperative pain.

Methods

We were interested in determining the postoperative effect of propacetamol administered intraoperatively after intraoperative remifentanil. Thirty-six adult women undergoing mammoplasty with remifentanil-based anesthesia were randomly assigned to receive propacetamol 2 g or placebo one hour before the end of surgery. After remifentanil interruption and tracheal extubation in recovery room, pain was assessed and intravenous titrated morphine was given. The primary end-point was the cumulative dose of morphine administered in the recovery room. The secondary end-points were the pain score after tracheal extubation and one hour after, the delay for obtaining a Simplified Numerical Pain Scale (SNPS) less than 4, and the incidence of morphine side effects in the recovery room.

For intergroup comparisons, categorical variables were compared using the chi-squared test and continuous variables were compared using the Student t test or Mann-Whitney U test, as appropriate. A p value less than 0.05 was considered as significant.

Results

In recovery room, morphine consumption was lower in the propacetamol group than in the placebo group (p = 0.01). Pain scores were similar in both groups after tracheal extubation and lower in the propacetamol group (p = 0.003) one hour after tracheal extubation. The time to reach a SNPS < 4 was significantly shorter in the propacetamol group (p = 0.02). The incidence of morphine related side effects did not differ between the two groups.

Conclusions

Intraoperative propacetamol administration with remifentanil based-anesthesia improved significantly early postoperative pain by sparing morphine and shortening the delay to achieve pain relief.

A randomized comparison of propofol and methohexital as general anesthetics for vacuum abortion

The objective of this study was to determine whether propofol and methohexital differ in their efficacy, acceptability, cost and side effects when used as the single anesthetic agent for inducing general anesthesia in first-trimester vacuum abortion. We randomized 400 unpremedicated American Society of Anesthesiologists grade I-II women to receive 1% propofol or 1% methohexital by intravenous bolus infusion during abortion. No ancillary anesthetic or adjunctive drugs were used. Visual analogue scale scores were used to grade preoperative patient anxiety and the quality of the anesthetic experience. All personnel outside the operating suites, except the data analyst, were blinded. Chi2, median, analysis of variance and Student's t-tests were used, as appropriate. There were no statistically significant differences in age, gravidity, parity, spontaneous and induced abortion, body mass index or gestational age. Mean total operating time and total drug dose were similar. Propofol use resulted in a significant reduction in the incidence of postoperative nausea (11.5% vs. 17.5%) or vomiting (3.5% vs. 7.0%) with a combined p (mean difference) = 0.002 (95% confidence interval of the mean difference 1.8%, 17.2%). Both the nursing and patient appraisals of the quality of the anesthetic experience favored propofol, but only the nursing scores reached statistical significance (p < 0.001). The cost differential was more than twofold greater for propofol patients, 9.51 dollars vs. 4.42 dollars. In our population of midwestern patients in a major urban area, propofol use had modest advantages over methohexital when used as single agents as judged by first recovery charge nurses, but patients found them equally acceptable.

Is pain prophylaxis in minor gynaecological surgery of clinical value? a double-blind placebo controlled study of paracetamol 1 g versus lornoxicam 8 mg given orally

Methods: In a prospective randomised placebo controlled double-blind study 210 ASA I-II women scheduled for elective termination of pregnancy received 1 g paracetamol, 8 mg lornoxicam or placebo orally 60 min before anaesthesia which was standardised with propofol, fentanyl and oxygen in nitrous oxide 1:2. Postoperative pain was assessed by VAS-score at 30 and 60 min after end of surgery and at discharge as primary endpoints. Need for rescue medication and time to discharge were secondary endpoints. Results: All patients had an uncomplicated course. Overall pain intensity was low, however, the patients pretreated with lornoxicam had significantly less pain after surgery, no difference could however, be seen in need for rescue medication or time to discharge between the three groups. Conclusion: General pain prophylaxis may be argued in minor gynaecological surgical procedures where postoperative pain is of low intensity. If general prophylaxis is to be given in minor gynaecological surgery, a non steroidal anti-inflammatory (NSAID) such as lornoxicam, seems more efficacious as compared to a standard dose of 1 g paracetamol.

The use of propofol for its antiemetic effect: a survey of clinical practice in the United States

STUDY OBJECTIVES

To investigate the use of propofol by anesthesiologists for its antiemetic effect and to compare our findings with published evidence.

DESIGN

Anonymous survey of U.S. anesthesiologists.

SETTING

American Society of Anesthesiologists' annual meeting.

MEASUREMENTS AND MAIN RESULTS

One hundred fifty anesthesiologists were surveyed on how they use propofol to achieve an antiemetic effect. A large majority (84%) of the anesthesiologists surveyed stated they used propofol for its antiemetic effect: 63% of those used propofol for induction only for cases lasting <1 h to achieve an antiemetic effect. In addition 37% used a "sandwich" technique, using propofol at the beginning and end of a case for a similar purpose. There is evidence that the antiemetic effect of propofol is associated with a defined plasma concentration range; mean, 343 ng/mL (10-90% confidence intervals [CI] 200-600 ng/mL). Simulation data demonstrated that after propofol 2 mg/kg, its concentration will drop below 350 ng/mL at 32 min. After 2 mg/kg and 20 mg within 10 min of the end of surgery, its concentration will drop below 350 ng/mL by 7 min after the 20 mg bolus dose. This finding suggests that the plasma concentrations of propofol, when used in these cases, will be below the effective range of antiemetic effect.

CONCLUSIONS

Many anesthesiologists used propofol for its antiemetic effect. There is strong evidence for its antiemetic efficacy after anesthesia maintained by a propofol infusion and also for its use in the postanesthesia care unit (PACU). However, there is little evidence to support its use purely at induction of anesthesia or as part of a "sandwich" technique in an attempt to reduce postoperative nausea and vomiting. This is especially true in cases lasting longer than a few minutes.