The effectiveness of preemptive analgesia varies according to the type of surgery: a randomized, double-blind study

Comparison of efficacy of thoracic paravertebral block with oblique subcostal transversus abdominis plane block in open cholecystectomy

BACKGROUND AND AIMS

Sensory afferent nerve branches of lower six thoracic and upper lumbar nerves innervate the anterior abdominal wall and are the therapeutic focus of local anesthetics to provide analgesia for the abdominal surgical incision. Central neuraxial and regional analgesia can provide better control of pain due to right subcostal incision used in open cholecystectomy and attenuate the need for opioids. The earlier studies which showed the benefit of the thoracic paravertebral block (TPVB) for analgesia after upper abdominal surgeries did not compare TPVB with oblique subcostal transversus abdominis plane (OSTAP) block. Therefore, the current study compares the analgesic efficacy of TPVB and OSTAP block in open cholecystectomy.

MATERIAL AND METHODS

Seventy consenting adults scheduled for open cholecystectomy were allocated to one of the two groups: ultrasound-guided TPVB (Group I) and ultrasound-guided OSTAP block (Group II). The primary objective of this study is to assess and compare tramadol consumption in 48 h in both the groups along with VAS in post anesthesia care unit, and then at 2, 4, 6, 8, 12, 24, and 48 h. The secondary objective of the study is to assess the incidence of PONV.

RESULTS

The number of doses of rescue analgesia required was less in Group I when compared with Group II (P < 0.001). Patients in Group I had significantly lower pain scores than Group II. Although in the initial 8 h, both groups had comparable pain scores, after 8 h, these scores were significantly lower in patients in Group I. Less postoperative nausea and vomiting was seen in Group I patients (11.7%) in comparison to Group II (18.1%).

CONCLUSION

Ultrasound-guided TPVB is superior to OSTAP block because of its association with decreased postoperative opioid consumption, lower VAS score, and reduction in opioid-related side effects. Thus, it should be strongly considered as a part of multimodal analgesia regimen in upper abdominal surgeries.

Preventive Epidural Analgesia in Bilateral Single-Stage Knee Arthroplasty: A Randomized Controlled Trial

INTRODUCTION

Although controversial, pre-emptive analgesia has shown some promise in preventing altered pain perception and reducing pain amplification after surgery. Hence, it has the potential to be more effective than a similar analgesic regimen started after surgery with an appropriate combination of patient category and analgesic modality. Hence, the present study was undertaken to evaluate the effect of preventive epidural analgesia in reducing pain severity and duration after bilateral single-stage knee arthroplasty.

METHODS

Fifty patients, 18-70 years, with American Society of Anesthesiologists physical status class I & II posted for bilateral single-stage knee replacement under regional anesthesia were randomly allocated into preventive versus postoperative epidural analgesia group to compare severity of post-operative pain, analgesic consumption, day of mobilization, C-reactive protein (CRP) levels, and hospital stay.

RESULTS

The pain score after surgery [2.0 (1.5, 2.0); 3.0 (1.5, 3.0), p = 0.005] and day of mobilization [(2. 92 ± 0. 28; 3. 31 ± 0. 48; p value 0.02)] were significantly lesser in the preventive epidural group. However, there was no difference in the hospital stay (9.92 ± 3.71 and 9.00 ± 2.12, p = 0.95) and analgesic consumption (65.38 ± 37.55 and 73.08 ± 43.85, p = 0.30). The preventive group had a larger drop in CRP and experienced a lesser number of days with pain after surgery as compared to the controls [(64.29 ± 21.29); (142.37 ± 80.04), p = 0.0001]. Six patients in the preemptive group (24%) and 13 of the control group (24 vs. 56.5%; p = 0.02) had chronic postsurgical pain.

CONCLUSIONS

Preventive epidural analgesia reduces the severity and number of chronic pain days after bilateral single-stage knee replacement.

TRIAL REGISTRATION

The study was registered in the Indian national registry (CTRI/2017/03/008240 on 28/03/2017).

Surgically-assisted abdominal wall blocks for analgesia after abdominoplasty: A prospective randomized trial

BACKGROUND

Abdominoplasty is a common aesthetic procedure. The transversus abdominis plane block (TAPB) and rectus sheath block (RSB) have proven efficacy as analgesic modality for abdominal surgeries. This study demonstrates post-abdominoplasty analgesic duration consequent to the three surgically infiltrated local anesthetic techniques: bilateral TAPB, bilateral RSB, and subcutaneous infiltration (SCI) of 0.25% bupivacaine.

METHODS

In this prospective randomized study, 48 adult patients scheduled for abdominoplasty were randomized into three groups: TAPB group (n = 16), RSB group (n = 16), and SCI group (n = 16) utilizing 40 mL of 0.25% bupivacaine for each block. In both TAPB and RSB groups, the block was performed bilaterally after plication of anterior abdominal wall, while in SCI group, the surgical incisional area was infiltrated before skin closure. Main outcome measures included visual analogue scale (VAS), at rest and during movement; the analgesic duration; and the total required doses of morphine in the first postoperative day.

RESULTS

A statistically significant longer analgesia was recorded in the TABP group compared with both the RSB and SCI groups. Statistically significant higher VAS scores in the SCI group 4 hours postoperatively was recorded, both at rest and during movement, compared with both TABP and RSB groups. Significant higher morphine consumption in the SCI group was compared with the other two groups.

CONCLUSIONS

Among the surgically infiltrated anesthetic techniques for abdominoplasty, bilateral TAPB was associated with longer postoperatively analgesic duration with lower morphine consumption in the first 24 hours compared with RSB and SCI.

The effect of pre-emptive analgesia on the level of postoperative pain in women undergoing surgery for breast neoplasm

AIM OF THE STUDY

Dynamic development of research on pain has resulted in the formulation of the concept of pre-emptive analgesia, which involves administration of analgesics before the first pain-producing stimulus appears. It is meant to prevent increased sensitivity to pain in the postoperative period. The aim of this study was to assess the possibilities of modifying the intensity of postoperative pain evaluated with the visual analogue scale (VAS) in patients after surgical treatment for breast neoplasm offered by pre-emptive analgesia.

MATERIAL AND METHODS

The intensity of postoperative pain was measured immediately after the surgery as well as 6, 12, 18, and 24 hours later in 100 women who had undergone surgery for breast tumour. The correlation between experienced pain and the type of analgesic administered pre-emptively, including metamizole, tramadol, ketoprofen, and placebo was examined. The effect of other correlates such as the extensiveness of surgery, systolic and diastolic blood pressure, and heart rate on the level of experienced pain as well as the usefulness of physiological parameters for its assessment were also analysed.

RESULTS

The conducted study demonstrated the effectiveness of tramadol (p = 0.004) and ketoprofen (p = 0.039) administered half an hour before the beginning of surgery, but there was no similar effect in the case of metamizole (p = 1.0). A positive correlation was observed between the level of experienced pain and blood pressure values (p < 0.001). Heart rate does not seem to be significantly linked with the intensity of experienced pain (p = 0.157).

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.

The effect of preemptive pudendal nerve block on pain after anterior and posterior vaginal repair

Introduction:

Anterior and posterior vaginal repair (APR) is a common surgery for women with prolapse of pelvic organs which creates post-operative pain because of damage of tissues that we should manage and control this pain. For this purpose, this study was conducted in order to evaluate the effect of preemptive pudendal nerve block on post-operative pain in anterior and posterior vaginal wall repair.

Materials and Methods:

In a double-blinded clinical trial study, 60 women candidates of APR were randomly divided to two groups. In both of them was injected 0.3 cc/kg bupivacaine 0.25% for the intervention group or normal saline for the control group in pudendal nerve tract with the guide of nerve stimulator. A visual analog scale was used to measure pain during the first 48 h after the surgery. Data were analyzed by repeated measures analysis of variance (ANOVA).

Results:

Compared with the intervention group, the control group experienced greater pain during rest and walking. There were significant differences between the two groups from the first post-operative hour (P = 0.003) until 48 h after the operation (P = 0.021). Furthermore, the mean ± SD values of pain in the sitting position was not significantly different between control and intervention groups at the same time (P = 0.340).

Conclusion:

Preemptive pudendal nerve block can reduce post-operative pain score in anterior and posterior vaginal wall repair and this method was suggested in anterior and posterior vaginal wall repair.

Gabapentin significantly decreases posthemorrhoidectomy pain: a prospective study

PURPOSE

Surgery for hemorrhoidectomy remains a painful procedure despite advances in pain management. Gabapentin is widely used for control of acute and chronic pain. Our aim was to evaluate the effect of gabapentin on posthemorrhoidectomy pain and opioid use.

METHODS

A prospective, open-label study. Patients requiring hemorrhoid surgery were recruited to be in control (standard of care) or treatment group (standard of care plus daily gabapentin).

RESULTS

Twenty-one treatment and 18 control patients were recruited. One patient from study group and two patients from control group were excluded due to failure to follow up. Pain levels for gabapentin group were significantly lower on postoperative days 1, 7, and 14 compared to the standard treatment group (3.68 vs. 6.82 p < 0.01, 2.68 vs. 5 p = 0.02 and 0.75 vs. 3.64 p < 0.001 respectively). There was a trend toward less opioids taken in gabapentin group for postoperative days 1, 7, and 14 (4.69 vs. 6.36; 2.13 vs. 2.73, and 0.125 vs. 0.9) but it did not reach statistical significance. The average hemorrhoidal grade and number of hemorrhoidal complexes removed was slightly higher in gabapentin group. Five control group patients experienced postoperative complications versus two gabapentin group patients. No gabapentin related complications were seen in the treatment group. The average cost of gabapentin course was $5.34 per patient.

CONCLUSIONS

Daily use of gabapentin in perioperative period significantly decreased reported levels of postoperative pain. This effective, inexpensive addition improves pain after hemorrhoid surgery. Randomized placebo-controlled studies would better define the usefulness of this medication for posthemorrhoidectomy pain.

Pre-emptive tramadol could reduce pain after ureteroscopic lithotripsy

PURPOSE

Optimal analgesia in ambulatory urology patients still remains a challenge. The aim of this study was to examine if the pre-emptive use of intravenous tramadol can reduce pain after ureteroscopic lithotripsy in patients diagnosed with unilateral ureteral stones.

MATERIALS AND METHODS

This prospective pilot cohort study included 74 patients diagnosed with unilateral ureteral stones who underwent ureteroscopic lithotripsy under general anesthesia in the Urology Clinic at the Clinical Center of Serbia from March to June 2012. All patients were randomly allocated to two groups: one group (38 patients) received intravenous infusion of tramadol 100 mg in 500 mL 0.9%NaCl one hour before the procedure, while the other group (36 patients) received 500 mL 0.9%NaCl at the same time. Visual analogue scale (VAS) scores were recorded once prior to surgery and two times after the surgery (1 h and 6 h, respectively). The patients were prescribed additional postoperative analgesia (diclofenac 75 mg i.m.) when required. Pre-emptive effects of tramadol were assessed measuring pain scores, VAS1 and VAS2, intraoperative fentanyl consumption, and postoperative analgesic requirement.

RESULTS

The average VAS1 score in the tramadol group was significantly lower than that in the non-tramadol group. The difference in average VAS2 score values between the two groups was not statistically significant; however, there were more patients who experienced severe pain in the non-tramadol group (p<0.01). The number of patients that required postoperative analgesia was not statistically different between the groups.

CONCLUSION

Pre-emptive tramadol did reduce early postoperative pain. The patients who received pre-emptive tramadol were less likely to experience severe post-operative pain.

Relevance of infiltration analgesia in pain relief after total knee arthroplasty

OBJECTIVE:

The aim of the study was to assess the effect of different types of anesthesia on pain intensity in early postoperative period.

PATIENTS AND METHODS:

A total of 87 patients (77 women, 10 men) scheduled for total knee arthroplasty (TKA) were assigned to receive either subarachnoid anesthesia alone or in combination with local soft tissue anesthesia, local soft tissue anesthesia and femoral nerve block and pre-emptive infiltration together with local soft tissue anesthesia. We assessed the pain intensity, opioid consumption, knee joint mobility, and complications of surgery.

RESULTS:

Subjects with pre-emptive infiltration and local soft tissue anesthesia had lower pain intensity on the first postoperative day compared to those with soft tissue anesthesia and femoral nerve block (P=0.012, effect size 0.68). Subjects who received pre-emptive infiltration and local soft-tissue anesthesia had the greatest range of motion in the operated knee at discharge (mean 90 grades [SD 7], P=0.01 compared to those who received subarachnoid anesthesia alone, and P=0.001 compared to those with subarachnoid together with soft tissue anesthesia).

CONCLUSION:

Despite the differences in postoperative pain and knee mobility, the results obtained throughout the postoperative period do not enable us to favour neither local nor regional infiltration anesthesia in TKA. Level of Evidence II, Prospective Comparative Study.

Postoperative analgesic effects of ultrasound-guided transversus abdominis plane block for open appendectomy

PURPOSE

Transversus abdominis plane (TAP) block is a newly developed and effective peripheral block involving the nerves of the anterior abdominal wall for lower abdominal surgery. We evaluated the postoperative analgesic efficacy of ultrasound-guided TAP block using 20 mL of 0.5% levobupivacaine in patients undergoing open appendectomy.

METHODS

Forty-four patients undergoing appendectomy were assigned either to undergo a right sided-TAP block (group I, n = 22), or to receive standard care (group II, n = 22). All patients received standard anesthetics, and the TAP block group received ultrasound-guided right side TAP block using 20 mL of 0.5% levobupivacaine after induction of anesthesia. All patients received acetaminophen, and nonsteroidal anti-inflammatory drug as required during the 48 postoperative hours. Each patients was assessed for time to first rescue analgesia, verbal numerical rating pain scores (VNRS), number of rescue analgesic demands, nausea, vomiting, pruritus, and drowsiness by a blinded investigator at 0, 1, 3, 6, 12, 24 and 48 hours postoperatively.

RESULTS

The TAP block group with levobupivacaine compared to the control group reduced VNRS significantly up to 12 hours postoperatively. There were no significant differences in time to first analgesia, number of rescue analgesics demands, nausea, vomiting, pruritus and drowsiness between the groups. There were no complications attributable to the TAP block.

CONCLUSION

Ultrasound-guided TAP block using 20 mL of 0.5% levobupivacaine provided effective postoperative analgesia during the 12 postoperative hours after an open appendectomy.

A randomized, double-blind, placebo-controlled trial of preemptive analgesia with bupivacaine in patients undergoing mastectomy for carcinoma of the breast

Background

In this prospective, randomized, placebo-controlled, double-blinded clinical trial we tested the hypothesis that preemptive analgesia with bupivacaine applied in the area of the surgical incision in patients undergoing mastectomy for breast cancer would reduce post-operative acute pain and would reduce the amount of analgesics used during surgery and in the post-operative period.

Material/Methods

Participants were assigned into 1 of 2 groups – with bupivacaine applied in the area of surgical incision or with placebo. We assessed the intraoperative consumption of fentanyl, the postoperative consumption of morphine delivered using a PCA method, and the subjective pain intensity according to VAS score reported by patients in the early post-operative period.

Results

Out of 121 consecutive cases qualified for mastectomy, 112 women were allocated randomly to 1 of 2 groups – group A (bupivacaine) and group B (placebo). The final study group comprised 106 breast cancer cases. Between the groups, a statistically significant difference was observed with respect to: lower fentanyl consumption during surgery (p=0.011), lower morphine (delivered by means of a PCA) consumption between the 4–12^th postoperative hours (p=0.02) and significantly lower pain intensity assessed according to VAS score at the 4^th and 12^th hours after surgery (p=0.004 and p=0.02 respectively) for the group A patients.

Conclusions

Preemptive analgesia application in the form of infiltration of the area of planned surgical incisions with bupivacaine in breast cancer patients undergoing mastectomy decreases post-operative pain sensation, limits the amount of fentanyl used during surgery, and reduces the demand for opiates in the hours soon after surgery.

Lack of preemptive analgesia by intravenous flurbiprofen in thyroid gland surgery: a randomized, double-blind and placebo-controlled clinical trial

BACKGROUND

Nowadays, increasingly more preemptive analgesia studies focus on postoperative pain; however, the impact of preemptive analgesia on perioperative opioid requirement is not well defined. This study was carried out in order to evaluate whether preoperative intravenous flurbiprofen axetil can reduce perioperative opioid consumption and provide postoperative analgesia in patients undergoing thyroid gland surgery.

METHODS

Ninety patients undergoing elective thyroid gland surgery were randomly assigned to three groups. Group A (Control) was administered Intralipid(®) 2 ml as a placebo 15 min before the cervical plexus block and at the end of the surgery; Group B (Routine analgesia) was administered a placebo 15 min before the cervical plexus block and flurbiprofen 50 mg at the end of the surgery; Group C (Preemptive analgesia) was administered intravenous flurbiprofen 50 mg 15 min before the cervical plexus block and a placebo at the end of the surgery. Sufentanil administration during the surgery and the 24 h satisfaction score on analgesic therapy were both recorded. The analgesic efficacy was assessed at 1, 2, 4, 6, 8, 12, and 24 hours after the surgery, based on visual analog scales.

RESULTS

Ninety patients were involved in the study. One patient from Group B did not have their scheduled surgery; eighty-nine patients completed the study. There were no significant differences in the patient demographics between the three groups. Visual analog scales: 1, 2, 4 h for Group A was significantly higher than Groups B and C (P<0.05); Sufentanil administration during surgery: Group C was obviously lower compared to Groups A and B (P<0.05); 24 h satisfaction score: Groups B and C were higher than Group A (P<0.05).

CONCLUSION

Preoperative administration of intravenous Flurbiprofen axetil reduced analgesic consumption during surgery, but not postoperative pain scores.

Prospective randomized trial of iliohypogastric-ilioinguinal nerve block on post-operative morphine use after inpatient surgery of the female reproductive tract

Objective

To determine the impact of pre-operative and intra-operative ilioinguinal and iliohypogastric nerve block on post-operative analgesic utilization and length of stay (LOS).

Methods

We conducted a prospective randomized double-blind placebo controlled trial to assess effectiveness of ilioinguinal-iliohypogastric nerve block (IINB) on post-operative morphine consumption in female study patients (n = 60). Patients undergoing laparotomy via Pfannenstiel incision received injection of either 0.5% bupivacaine + 5 mcg/ml epinephrine for IINB (Group I, n = 28) or saline of equivalent volume given to the same site (Group II, n = 32). All injections were placed before the skin incision and after closure of rectus fascia via direct infiltration. Measured outcomes were post-operative morphine consumption (and associated side-effects), visual analogue pain scores, and hospital length of stay (LOS).

Results

No difference in morphine use was observed between the two groups (47.3 mg in Group I vs. 45.9 mg in Group II; p = 0.85). There was a trend toward lower pain scores after surgery in Group I, but this was not statistically significant. The mean time to initiate oral narcotics was also similar, 23.3 h in Group I and 22.8 h in Group II (p = 0.7). LOS was somewhat shorter in Group I compared to Group II, but this difference was not statistically significant (p = 0.8). Side-effects occurred with similar frequency in both study groups.

Conclusion

In this population of patients undergoing inpatient surgery of the female reproductive tract, utilization of post-operative narcotics was not significantly influenced by IINB. Pain scores and LOS were also apparently unaffected by IINB, indicating a need for additional properly controlled prospective studies to identify alternative methods to optimize post-surgical pain management and reduce LOS.

Randomized trial of preemptive local analgesia in vaginal surgery

Preemptive analgesia in vaginal surgery has had conflicting efficacy reported in the existing literature. This study was designed to clarify the usefulness of preemptive local analgesia (PLA) in patients undergoing vaginal hysterectomy. A prospective, randomized, double-blinded trial of PLA in 90 women undergoing vaginal hysterectomy was conducted. PLA consisted of 20 ml of 0.5% bupivacaine with 1:200,000 epinephrine injected in a paracervical-type fashion. Total narcotic use and pain (using a visual analog scale (VAS)) was recorded at 30 min, 3, 12, and 24 h postoperatively. The mean total dose of narcotic was significantly less in the PLA group versus the placebo group (P = 0.009) at every time point postoperatively. Additionally, the mean pain VAS 30 min and 3 h postoperatively was 43% (P = 0.003) and 33% (P = 0.02) lower, respectively, in the PLA group. PLA with bupivacaine prior to vaginal hysterectomy is associated with significantly lower pain scores and a reduction in narcotic use postoperatively.

Postthoracotomy pain management problems

Pain after thoracotomy is very severe, probably the most severe pain experienced after surgery. Thoracic epidural analgesia has greatly improved the pain experience and its consequences and has been considered the standard for pain management after thoracotomy. This view has been challenged recently by the use of paravertebral nerve blocks. Nevertheless, severe ipsilateral shoulder pain and the prevention of the postthoracotomy pain syndrome remain the most important challenges for management of postthoracotomy pain.

Preemptive analgesia with local lidocaine infiltration for single-level open disc operation

To evaluate the impact of preemptive local analgesia at the incision site for postoperative pain in patients undergoing disc operation. In this prospective, randomized, double-blinded, placebo-controlled study 166 patients were assigned to either lidocaine (n = 83) or placebo (n = 83) groups. The incision site was infiltrated with either 20 mL of 2% lidocaine and 0.9% saline in lidocaine group or 0.9% saline before the incision. Morphine (5 mg) was used for postoperative pain treatment. Postoperative pain was measured with Visual Analog Scale (VAS) in 6, 12, 24 and 48 h. Data were analyzed with SPSS software, using Chi-square and t-tests. The groups were matched for age, sex, type of operation, mean length of hospital stay and mean length of operation. Statistical analysis revealed no significant difference in visual analog scores of pain severity at 6, 12, 24 and 48 h after surgery between lidocaine and placebo groups (6 h: 38.22 +/- 26.87 vs. 34.52 +/- 24.43, p = 0.35; 12 h: 33.26 +/- 28.83 vs. 28.01 +/- 24.71, p = 0.20; 24 h: 26.71 +/- 23.31 vs. 22.85 +/- 22.48, p = 0.27; 48 h 16.35 +/- 10.16 vs. 15.23 +/- 8.90 p = 0.45). The amount of narcotics used post operatively had no meaningful difference in the groups (lidocaine 10.07 +/- 8.24 mg vs. placebo 10.54 +/- 9.31 mg p = 0.73). Preemptive analgesia with lidocaine 2% used subcutaneously before skin incision has no effect in reducing postoperative pain, narcotics demand and duration of hospital stay.

Impact on postoperative pain of long-lasting pre-emptive epidural analgesia before total hip replacement: a prospective, randomised, double-blind study

Clinical studies on pre-emptive analgesia have produced inconsistent results. We conducted a clinical study investigating the effect of long-lasting pre-emptive epidural analgesia on consumption of analgesics and acute pain. Forty-two patients scheduled for elective hip replacement for osteo-arthritis were randomly assigned to receive, on the day before operation, either 5 ml.h(-1) ropivacaine 0.2% (study group, n = 21) or 5 ml.h(-1) saline (control group, n = 21). Postoperative analgesia was achieved in both groups by patient-controlled epidural analgesia (PCEA) with ropivacaine 0.2%. The main outcome measure was consumption of local anaesthetics. Additional parameters included visual analogue pain scale (VAS) scores, consumption of rescue analgesics, requests for PCEA boluses, and side-effects. The pre-operative parameters and pain scores were similar in the two groups. Epidural blocks provided sufficient operative analgesia in all patients. Pre-emptive analgesia was continued for 11-20 h and led to significantly decreased pain scores before surgery. The consumption of local anaesthetics was decreased postoperatively in the study group (194 mg vs. 284 mg in the postoperative period). Furthermore, bolus requests occurred more frequently in the control group. VAS scores did not differ significantly between groups. Long-lasting "pre-emptive" epidural analgesia decreases postoperative pain with improved pain control.

Vitreoretinal surgery: pre-emptive analgesia

AIM

Vitrectomies are performed either under general anesthesia (GA), local anesthesia (LA), or a combination of both. Postoperative pain is expected to be less in patients with LA because of prolonged action of the local anaesthetic. Pre-emptive analgesia is based on the idea that analgesia initiated before a nociceptive event will be more effective than analgesia commenced afterwards. The authors compared postoperative analgesia in patients with GA combined with preoperative or postoperative LA.

METHODS

90 patients scheduled for vitrectomy without buckling were enrolled in the study. 60 patients underwent GA, 30 without LA, 15 with preoperative LA, and 15 with postoperative LA. 30 patients received LA alone. Subjective postoperative pain was determined using the visual analogue scale.

RESULTS

Postoperative pain was less under LA alone compared to GA alone (p < 0.0001). Additional preoperative application of LA resulted in less pain than additional postoperative application (p <0.05). Additional postoperative peribulbar aneasthesia did not differ from GA alone.

CONCLUSION

The authors conclude that LA alone or preoperatively in addition to GA provides the best comfort for the patient in vitreoretinal surgery.