An evaluation of morphine and oxymorphone administered via patient-controlled analgesia (PCA) or PCA plus basal infusion in postcesarean-delivery patients

Evaluation of basal rate infusion in intravenous patient-controlled analgesia for post-cesarean section pain management: A randomized pilot study

OBJECTIVE

Administering opioids via intravenous patient-controlled analgesia is a prevalent approach for managing postoperative pain. Nevertheless, due to concerns about opioid-related side effects and the potential for opioid tolerance, there is a growing emphasis on adopting opioid-sparing techniques for postoperative pain management. We aimed to investigate the effect of adding a basal rate infusion in fentanyl-based IVA following a cesarean section (CS).

METHOD

Forty-eight patients, who received pain management through IVA after CS, were assigned randomly into 3 groups based on the background rate setting: Group 0 (0 mcg/hour, n = 16), Group 1 (15 mcg/hour, n = 16), and Group 2 (30 mcg/hour, n = 16). We assessed the impact of the basal infusion rate on opioid consumption and the visual analog scale (VAS) scores during the first 48 hours post-CS and also investigated opioid-induced side effects and the requirement for rescue analgesics in the ward during the first 48 hours after CS.

RESULTS

In the initial 24 hours following CS, fentanyl consumption significantly increased in Group 2 compared with Group 0 and Group 1 (P = .037). At 24 hours, VAS scores both at rest and during movement, tended to decrease, as the basal rate increased; however, no significant differences were observed between the groups (P = .218 and 0.827, respectively). Between the first 24- and 48-hours post-CS, fentanyl consumption showed a marked increase in both Group 1 and Group 2 compared to Group 0 (P < .001). At 48 hours, the VAS scores at rest displayed a trend toward reduction; however, no significant differences between groups were evident (P = .165). Although the incidence of opioid-induced complications was noted, no statistically significant differences were recorded between groups during the initial 24 hours and subsequent 24 to 48 hours period (P = .556 and P = .345, respectively).

CONCLUSION

The inclusion of a basal fentanyl infusion in the IVA protocol did not provide any advantages over an IVA devoid of a basal rate infusion in managing acute pain following CS.

Effects of opioids administered via intravenous or epidural patient-controlled analgesia after caesarean section: A network meta-analysis of randomised controlled trials

BACKGROUND

Post-caesarean section analgesia is important physiologically and psychologically for both mothers and infants. Patient-controlled analgesia is a well-established method of administering opioids for postoperative pain. However, to date, no study has systematically investigated the effects of opioids administered through intravenous patient-controlled analgesia (IVPCA) or patient-controlled epidural analgesia (PCEA) in parturients who have undergone caesarean section.

METHODS

This systematic review and network meta-analysis aimed to evaluate the analgesic and adverse effects of opioids administered via IVPCA or PCEA in parturients who have undergone a caesarean section. PubMed, Embase, Scopus, Web of Science, and Cochrane Library were searched from inception through 02 10, 2022 for relevant records. Randomised controlled trials (RCTs) that compared opioids administered via IVPCA or PCEA and reported outcomes of interest were included. Studies were excluded if the solution for patient-controlled analgesia contained antiemetics and/or other analgesics in addition to opioids. The methodological quality of RCTs was assessed using the revised Cochrane Risk of Bias Tool. Summary data were extracted from each eligible study. The primary outcome was pain intensity, and the secondary outcomes were opioid-related adverse effects. Frequentist network meta-analyses were performed using a contrast-based random-effects model. This study is registered with PROSPERO, CRD42021254040.

FINDINGS

Twenty-three studies with 2589 parturients were included. Compared with IVPCA morphine as a reference treatment, PCEA fentanyl had better analgesic effects at 4 h (mean difference [MD] in the visual analogue scale score, -0.75; 95% confidence interval [CI] [-1.16, -0.34]) and 8 h (MD, -0.93; 95% CI [-1.57, -0.28]) and yielded lower odds of developing nausea/vomiting (odds ratio [OR], 0.27; 95% CI [0.09, 0.80]) and sedation/drowsiness (OR, 0.22; 95% CI [0.11, 0.45]). However, PCEA fentanyl may be more likely to cause pruritus than IVPCA treatments.

INTERPRETATION

Considering the analgesic efficacy; opioid-induced nausea, vomiting, and sedation; and the well-being of breastfed infants, PCEA fentanyl may be the treatment of choice for post-caesarean section analgesia.

FUNDING

The Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation (TCRD-TPE-111-27).

Bilateral ultrasound-guided erector spinae plane block versus wound infiltration for postoperative analgesia in lumbar spinal fusion surgery: a randomized controlled trial

PURPOSE

Both erector spinae plane block and wound infiltration are used to improve analgesia following spinal fusion surgery. Herein, we compared the analgesic effect of bilateral erector spinae plane block with wound infiltration in this patient population.

METHODS

In this randomized trial, 60 patients scheduled for elective open posterior lumbar interbody fusion surgery were randomized to receive either ultrasound-guided bilateral erector spinae plane block before incision (n = 30) or wound infiltration at the end of surgery (n = 30). Both groups received standardized general anesthesia and postoperative analgesia, including patient-controlled analgesia with sufentanil and no background infusion. Opioid consumption and pain intensity were assessed at 2, 6, 12, 24, and 48 h after surgery. The primary outcome was cumulative opioid consumption within 24 h after surgery.

RESULTS

All 60 patients were included in the intention-to-treat analysis. The equivalent dose of sufentanil consumption within 24 h was significantly lower in patients given erector spinae plane block (median 11 μg, interquartile range 5-16) than in those given wound infiltration (20 μg, 10 to 43; median difference - 10 μg, 95% CI - 18 to - 3, P = 0.007). The cumulative number of demanded PCA boluses was significantly lower with erector spinae plane block at 6 h (median difference - 2, 95% CI - 3 to 0, P = 0.006), 12 h (- 3, 95% CI - 6 to - 1, P = 0.002), and 24 h (- 5, 95% CI - 8 to - 2, P = 0.005) postoperatively. The proportion given rescue analgesia was also significantly lower in patients given erector spinae plane block group within 48 h (relative risk 0.27, 95% CI 0.07 to 0.96, P = 0.037). There were no statistical differences in pain intensity at any timepoints between groups. No procedure-related adverse events occurred.

CONCLUSIONS

Compared with wound infiltration, bilateral ultrasound-guided erector spinae plane block decreases short-term opioid consumption while providing similar analgesia in patients following lumbar spinal fusion surgery. Chinese Clinical Trial Registry: ChiCTR2100053008.

The effect of newly designed dual-channel elastomeric pump for intravenous patient-controlled analgesia after total laparoscopic hysterectomy: a randomized, double-blind, prospective study

BACKGROUND

A newly designed intravenous patient-controlled analgesia (PCA) device with a dual-channel elastomeric infusion pump has been recently introduced. One channel is a continuous line with a constant flow rate basal infusion, while the other channel has an adjustable flow rate and bolus function and is labeled as a selector-bolus channel. This study compared dual and single-channel intravenous PCA in terms of clinical effect and quality of recovery.

METHODS

Eighty-four patients undergoing total laparoscopic hysterectomy were randomly allocated to a 1-channel group (n = 41) or a 2-channel group (n = 43). Only the selector-bolus channel was utilized, but the continuous channel was not utilized in the 1-channel group, but both channels were utilized in the 2-channel group. In the 1-channel group, 16 μg/kg of fentanyl, 2 mg/kg of ketorolac, and 12 mg of ondansetron with normal saline were administered to the selector-bolus channel and normal saline only in the continuous channel for blinding. In the 2-channel group, 16 μg/kg of fentanyl was administered to the selector-bolus channel, and ketorolac (2 mg/kg) and ondansetron (12 mg) were administered via the continuous channel. The quality of recovery was evaluated preoperatively and 24 h postoperatively using the Quality of Recovery-40 (QoR-40). Cumulative PCA consumption, postoperative pain rated using the numeric rating scale (NRS; during rest/cough), and postoperative nausea were evaluated 6, 12, 24, 36, and 48 h after surgery. Incidence of vomiting and use of antiemetics and rescue analgesics was measured.

RESULTS

The 24-h postoperative QoR-40 score was higher in the 2-channel group than in the 1-channel group (P=0.031). The incidence of nausea at 12 h and 36 h was significantly higher in the 1-channel group (P=0.043 and 0.040, respectively), and antiemetic use was more frequent in the 1-channel group (P=0.049). Patient satisfaction was higher in the 2-channel group (P=0.036). No significant differences were observed in pain scores during resting/cough or cumulative PCA consumption.

CONCLUSIONS

The 2-channel PCA showed better patient satisfaction with higher QoR-40 during the recovery compared with the 1-channel PCA. Better satisfaction was associated with lower nausea and reduced rescue antiemetics by maintaining the infusion of adjuvant analgesic agents and antiemetic agents constantly by utilizing dual channels.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov , NCT04082039 on 9 September 2019.

Effect of Fentanyl-Based Intravenous Patient-Controlled Analgesia with and without Basal Infusion on Postoperative Opioid Consumption and Opioid-Related Side Effects: A Retrospective Cohort Study

Purpose

We aimed to investigate the effect of a basal opioid infusion in fentanyl-based intravenous patient-controlled analgesia (IV-PCA) on postoperative opioid consumption, pain intensity, and occurrence of opioid-related side effects.

Patients and Methods

We retrospectively reviewed 2097 consecutive patients who received IV-PCA after elective general, thoracic, urologic, and plastic surgery under general anesthesia between June 2019 and October 2019. The patients were divided into two groups: IV-PCA with basal infusion (basal group) and IV-PCA without basal infusion (no basal group). We performed a propensity score matching (PSM) analysis to adjust for baseline differences between both groups. We compared the fentanyl PCA consumption (mcg), pain intensity, rescue analgesic administration, and occurrence of opioid-related side effects (nausea, vomiting, somnolence or dizziness, and overall side effects) during the first 48 hours postoperatively between the two groups before and after PSM.

Results

We analyzed 1317 eligible patients. Of these, 757 (57.5%) patients received IV-PCA without basal infusion. The PSM of the total cohort yielded 539 pairs of cases. After PSM, the fentanyl PCA consumption was significantly lower in the no basal group at 48 hours postoperatively as compared to the basal group (at 24 hours, the median difference: −80 mcg, P<0.001, 95% CI=−112 – −45 mcg; at 48 hours, the median difference: −286 mcg, P<0.001, 95% CI=−380 – −190 mcg), without significantly increasing pain intensity and administration of rescue analgesia. The occurrence of overall opioid-related side effects was also significantly lower in the no basal group (at 24 hours: 31.0% vs 23.0%, OR=0.67, P=0.003, 95% CI=0.51 – 0.87; at 48 hours: 18.9% vs 11.0%, OR=0.48, P<0.001, 95% CI=0.31 – 0.75).

Conclusion

Basal infusion of fentanyl-based IV-PCA was significantly associated with an increase in fentanyl consumption and the occurrence of opioid-related side effects in postsurgical patients.

Comparison between Multisite Infiltration Analgesia versus Adductor Canal Block for Pain Management in Total Knee Arthroplasty: A Prospective Study

Background:

Severe acute postoperative pain after total knee arthroplasty (TKA) may cause significant morbidity to patients. Recent techniques such as peripheral nerve blocks have shown promising hope in providing appropriate pain control without systemic side effects. Adductor canal block (ACB) and multisite infiltration analgesia (MIA) are two techniques that are proven to be effective individually.

Aim:

This study aims to compare the efficacy of ACB versus MIA in postoperative analgesia and functional recovery after unilateral knee arthroplasty.

Settings and Design:

A prospective study was conducted between July 2016 and December 2016 involving 200 patients undergoing unilateral TKA.

Materials and Methods:

Patients were either administered MIA (Group I, n = 100 patients) or ACB (Group II, n = 100 patients). All the patients were assessed for severity of pain by visual analog scale (VAS) at 8, 24, and 48 h postoperatively and knee range of motion (ROM) at 48 h after surgery.

Statistical Analysis:

The Statistical Package for the Social Sciences (SPSS 19.0, SPSS Inc., Chicago, IL, USA) was used for descriptive and inferential analysis.

Results:

Patients who received MIA showed significantly better VAS scores 8, 24, and 48 h after surgery. Furthermore, this subset of patients showed a marginally better ROM postoperatively. However, there was no difference number of patients requiring rescue analgesia for breakthrough pain or technique-related problems between both groups.

Conclusion:

This study demonstrates that MIA is a safe technique that provides effective analgesia at 8, 24, and 48 h postoperatively. This leads to faster rehabilitation compared to ACB in patients undergoing TKA.

Ultrasound-Guided Motor-Sparing Knee Blocks for Postoperative Analgesia Following Total Knee Arthroplasty: A Randomized Blinded Study

BACKGROUND

Pain following total knee arthroplasty (TKA) is often severe and can inhibit rehabilitation. Motor-sparing analgesic techniques such as periarticular infiltrations and adductor canal blocks have been popularized for knee analgesia since they preserve motor strength and permit early mobilization. Our primary objective was to compare the duration of analgesia from motor-sparing blocks with that of a standard periarticular infiltration. We used the time to first rescue analgesia as the end point.

METHODS

We randomized 82 patients scheduled for elective TKA to receive either the preoperative motor-sparing block (0.5% ropivacaine, 2.5 μg/mL of epinephrine, 10 mg of morphine, and 30 mg of ketorolac) or intraoperative periarticular infiltration (0.3% ropivacaine, 2.5 μg/mL of epinephrine, 10 mg of morphine, and 30 mg of ketorolac). For the motor-sparing block, we modified the ultrasound-guided adductor canal block by combining it with a lateral femoral cutaneous nerve block and posterior knee infiltration. The patients, surgeons, anesthetists administering the blocks, and outcome assessors all remained blinded to group allocation. Our primary outcome was duration of analgesia (time to first rescue analgesia). Secondary outcomes included quadriceps strength, function, side effects, satisfaction, and length of hospital stay.

RESULTS

The duration of analgesia was significantly longer (mean difference, 8.8 hours [95% confidence interval = 3.98 to 13.62], p < 0.01) for the motor-sparing-block group (mean [and standard error], 18.1 ± 1.7 hours) compared with the periarticular infiltration group (mean, 9.25 ± 1.7 hours). The infiltration group had significantly higher scores for pain at rest for the first 2 postoperative hours and for pain with knee movement at 2 and 4 hours. There were no significant differences between groups with regard to any other secondary outcomes.

CONCLUSIONS

In patients undergoing a TKA, a motor-sparing block provides longer analgesia than periarticular infiltration with retention of quadriceps muscle strength, function, patient satisfaction, and a short hospital stay.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Ketorolac, Oxymorphone, Tapentadol, and Tramadol: A Comprehensive Review

Pain remains a tremendous burden on patients and for the health care system, with uncontrolled pain being the leading cause of disability in this country. There are a variety of medications that can be used in the treatment of pain, including ketorolac, oxymorphone, tapentadol, and tramadol. Depending on the clinical situation, these drugs can be used as monotherapy or in conjunction with other types of medications in a multimodal approach. A strong appreciation of pharmacologic properties of these agents and potential side effects is warranted for clinicians.

Which analgesic mixture is appropriate for periarticular injection after total knee arthroplasty? Prospective, randomized, double-blind study

PURPOSE

Although the analgesic effect of periarticular injection after total knee arthroplasty (TKA) has been well documented, the gold standard for drug combination has not yet been established. In this study, the analgesic effects of six different drug combinations were compared.

METHODS

A total of 256 patients undergoing TKA for primary osteoarthritis were randomized into one of six groups: a control group (saline solution, epinephrine, and cefazolin, n = 42), Group 1 (ropivacaine, n = 43), Group 2 (ropivacaine + morphine, n = 43), Group 3 (ropivacaine + ketorolac, n = 42), Group 4 (ropivacaine + morphine + ketorolac, n = 43), and Group 5 (ropivacaine + morphine + ketorolac + methylprednisolone, n = 43). Pain level assessed by visual analogue scale (VAS) and opioid consumption were primary outcomes. The incidence of complications, range of motion (ROM), C-reactive protein (CRP) value, and the amount of post-operative blood drainage were also compared.

RESULTS

Patients in Groups 4 and 5 complained less pain than the control group for the first 12 h after surgery, and the patients in the other groups showed less pain only during the initial 6 h after surgery. Groups 4 and 5 also showed less opioid consumption than the control group during the 24 h period after surgery. Patients in Group 5 showed no significant difference in VAS score and opioid consumption compared with Group 4, but they had lower CRP value and greater ROM than any other groups at post-operative day 2 and day 4.

CONCLUSION

The combination of ropivacaine, morphine, and ketorolac showed a significantly stronger and sufficiently synergistic analgesic effect without adding methylprednisolone in periarticular injection after TKA. The clinical relevance of the study is that the combination of ropivacaine, morphine, and ketorolac can be a good option for periarticular injection following TKA in terms of synergistic analgesic effect and efficiency of drug combination.

Efficacy of multimodal perioperative analgesia protocol with periarticular medication injection in total knee arthroplasty: a randomized, double-blinded study

Pain control is necessary for successful rehabilitation and outcome after total knee arthroplasty. Our goal was to compare the clinical efficacy of periarticular injections consisting of a long-acting local anesthetic (ropivacaine) and epinephrine with and without combinations of an α2-adrenergic agonist (clonidine) and/or a nonsteroidal anti-inflammatory agent (ketorolac). In a double-blinded controlled study, we randomized 160 patients undergoing total knee arthroplasty to receive 1 of 4 intraoperative periarticular injections: Group A, ropivacaine, epinephrine, ketorolac, and clonidine; Group B, ropivacaine, epinephrine, and ketorolac; Group C, ropivacaine, epinephrine, and clonidine; Group D (control), ropivacaine and epinephrine. Compared with Group D, Group A and B patients had significantly lower postoperative visual analog pain scores and nurse pain assessment and Group C patients had a significantly greater reduction in physical therapist pain assessment. We found no differences in other parameters analyzed.

Oral administration of aprepitant to prevent postoperative nausea in highly susceptible patients after gynecological laparoscopy

PURPOSE

The use of opioids following surgery is associated with a high incidence of postoperative nausea and vomiting (PONV). We conducted a prospective, randomized, double-blind, placebo-controlled study to investigate the effect of orally administered aprepitant, a neurokinin-1 receptor antagonist, for reducing PONV in patients with fentanyl-based, patient-controlled analgesia (PCA) given intravenously after gynecological laparoscopy.

METHODS

One hundred and twenty female patients (ages 21-60) undergoing laparoscopic hysterectomy were randomly allocated to receive 80 mg (A80 group, n = 40) or 125 mg aprepitant (A125 group, n = 40) or placebo (control group, n = 40) orally 2 h before anesthesia induction. Anesthesia was maintained with isoflurane and remifentanil, and PCA IV using fentanyl and ketorolac were provided for 48 h after surgery. Incidences of nausea, vomiting/retching, and use of rescue antiemetics were recorded at 2, 24, and 48 h after surgery. Complete response was defined as no PONV and no need for rescue treatment.

RESULTS

The incidence of complete response was significantly lower in the A80 and A125 groups than in controls, 56 % and 63 %, vs. 28 %, respectively, P = 0.007 and P = 0.003, respectively, during the first 48 h, and 65 % and 65 % vs. 38 %, respectively, both P = 0.025, during the first 2 h. However, there were no statistically significant differences between A80 and A125 groups in the incidences of complete response and PONV during the study period.

CONCLUSIONS

Aprepitant 80 mg orally was effective in lowering the incidence of PONV in the first 48 h after anesthesia in patients receiving fentanyl-based PCA after gynecological laparoscopy.

Morphine at "sub-analgesic" background infusion rate plus low-dose PCA bolus control pain better and is as safe as twice a bolus-only PCA regimen: a randomized, double blind study

Morphine for postoperative pain control is commonly titrated via intravenous patient-controlled analgesia (IV-PCA). An IV morphine background infusion is rarely used. We investigated whether analgesia is effectively attained and morphine consumption is reduced if PCA titration is coadjuvated by a continuous infusion protocol. Following colorectal cancer surgery, consenting patients were randomized to receive a minimal ("sub-analgesic") dose of morphine 0.01 mg/kg/h background infusion plus a 0.01 mg/kg bolus (BI), or a 1.5mg bolus-only morphine (B0) (bolus ratio ∼1:2). Bolus lockout time was 7 min in either case. All patients received 0.1mg/kg morphine before protocol initiation, and diclofenac 75 mg intramuscularly b.i.d. during the study period, lasting 48 h. Eighty-six patients (51 males, age 26-95 years) participated in the study. The total mean morphine consumption during the 48 h was 25% lower in the BI than in the B0 group (P<0.05). Although the former applied the PCA device for boluses 19% less than the latter (P<0.05), their pain score was lower (P<0.05) most of the time, and they reported greater satisfaction (P<0.05) on a 10-scale numerical rating score. Pre- and postoperative vital signs were similar for both groups. No patient depicted hypoxemia or lapsed into deep sedation. Four BI and three B0 patients required treatment for postoperative nausea and vomiting. One BI patient had transient pruritus and one B0 69-year individual became disoriented 24h into treatment; either event subsided soon after stopping their respective regimen without the need for treatment. The main conclusions of the results are that very-low-dose background morphine infusion combined with small-dose PCA boluses may provide better pain relief, lower morphine consumption, and minimal complication rate as a 1.5mg PCA bolus-only protocol.

Patient-controlled versus nurse-controlled post-operative analgesia after caesarean section

BACKGROUND

The aim of this study was to compare the differences in the quality of analgesia by patient-controlled analgesia (PCA) and nurse-controlled analgesia (NCA) for post-caesarean section analgesia.

MATERIALS AND METHODS

350 women who undertake elective cesarean section were assigned to the three groups. Group I (n=200), IV-PCA morphine; group II (n=100), IV-PCA methadone; group III (n=50) NCA morphine. Data collected during the 24 h observation period included visual analog scale (VAS) pain and patient satisfaction scores, the incidence of nausea and vomiting, severe sedation and pruritis.

RESULTS

VAS pain scores for each time at which it was evaluated were higher for NCA group than other groups. Also patient satisfaction was significantly increased in the IV-PCA Group as compared with group III. The prevalence of pruritis was higher for NCA group than other groups.

CONCLUSION

In post caesarean section, PCA morphine or methadone improves 24-h VAS compared with NCA.

Oxymorphone: a review

Oxymorphone (oxymorphone hydrochloride) (14-hydroxy-dihydromorphinone), a semisynthetic mu-opioid agonist, was first approved by the US Food and Drug Administration in 1959. Oxymorphone is considered a more potent opioid than its parent compound, morphine. Recently, an immediate-release and long-acting oral formulation of this drug was developed that makes oxymorphone a new option in treating moderate to severe pain. This article reviews the pharmacodynamics, pharmacology, and clinical efficacy for this new option in treating moderate to severe pain.

Efficacy and safety of oxymorphone extended release in chronic low back pain: results of a randomized, double-blind, placebo- and active-controlled phase III study

This multicenter, randomized, double-blind, placebo- and active-controlled trial was conducted to compare the analgesic efficacy and safety of oxymorphone extended release (ER) with placebo and oxycodone controlled release (CR) in ambulatory patients with moderate to severe chronic low back pain requiring opioid therapy. Patients (N = 213) aged 18 to 75 years were randomized to receive oxymorphone ER (10 to 110 mg) or oxycodone CR (20 to 220 mg) every 12 hours during a 7- to 14-day dose-titration phase. Patients achieving effective analgesia at a stable opioid dose entered an 18-day double-blind treatment phase and either continued opioid therapy or received placebo. With stable dosing throughout the treatment phase, oxymorphone ER (79.4 mg/day) and oxycodone CR (155 mg/day) were superior to placebo for change from baseline in pain intensity as measured on a visual analog scale; the LS mean differences were -18.21 and 18.55 (95% CI, -25.83 to -10.58 and -26.12 to -10.98, respectively; P = .0001). Use of rescue medication was 20 mg per day. Adverse events for the active drugs were similar; the most frequent were constipation and sedation. Oxymorphone ER and oxycodone CR were generally safe and effective for controlling low back pain. Oxymorphone ER was equianalgesic to oxycodone CR at half the milligram daily dosage, with comparable safety.

PERSPECTIVE

Definitive studies of long-acting opioids in patients with chronic low back pain are lacking. We report the results of a multicenter, randomized, placebo-controlled, double-blind study evaluating the analgesic efficacy and safety of oxymorphone ER and oxycodone CR in opioid-experienced patients with chronic low back pain.

Postoperative pain management in obstetric anesthesia–new challenges and solutions

The current understanding of pain processing mechanisms, the different pharmacologic drugs, and other nonpharmacologic means that can be used to manage postobstetric operation pain are reviewed.

A background infusion of morphine does not enhance postoperative analgesia after cardiac surgery

PURPOSE

To compare the effects of patient-controlled analgesia (PCA), with or without a background infusion of morphine on postoperative pain relief and stress response after cardiac anesthesia.

METHODS

With University Ethics approval, 35 consenting adults undergoing elective open-heart surgery were randomly assigned preoperatively in a double-blind fashion to receive either morphine PCA alone (Group I, n = 15) or morphine PCA plus a continuous basal infusion (Group II, n = 14) for 44 hr postoperatively. Pain scores with visual analogue scale (VAS) at rest, deep inspiration and with cough, sedation scores, stress hormone levels [cortisol, adrenocorticotropin (ACTH) and growth hormone (GH)] and morphine consumption were assessed, and serum morphine levels were measured at four, 20, 28 and 44 hr after surgery. Adverse effects including nausea, vomiting, constipation, urinary retention and pruritus were noted. Total blood, fluid requirements, drainage and urinary output were recorded.

RESULTS

Postoperative morphine consumption at 44 hr was less in Group I (29.43 +/- 12.57 mg) than in Group II (50.14 +/- 16.44 mg), P = 0.0006. There was no significant difference between groups in VAS scores, GH levels, blood levels of morphine and adverse effects. While VAS scores, ACTH and GH levels decreased significantly in both groups, plasma cortisol levels increased significantly in Group I only at four hours. In Group II, ACTH and cortisol were higher at four and 44 hr respectively.

CONCLUSION

PCA with morphine effectively controlled postoperative pain after cardiac surgery. The addition of a background infusion of morphine did not enhance analgesia and increased morphine consumption.

Pain relief and safety after major surgery. A prospective study of epidural and intravenous analgesia in 2696 patients

BACKGROUND

Adverse effects may still limit the use of continuous epidural and intravenous analgesia in surgical wards. This study postulated that postoperative epidural analgesia was more efficient, and had fewer side-effects than intravenous morphine. The aim was to investigate efficacy, adverse effects and safety of the treatments in a large patient population.

METHODS

During a five-year period 2696 patients undergoing major surgery, received either epidural or intravenous analgesia for postoperative pain relief. The patients were prospectively monitored in surgical wards. Pain was evaluated with a numeric rating scale (0-10) at rest/mobilization. Treatment duration, respiratory depression, sedation/hallucinations/nightmares/confusion, nausea/vomiting, pruritus, orthostatism/leg weakness, and insufficient pain relief were registered. Pain relief for all patients aimed at a pain scoring of less than 4 at rest.

RESULTS

Epidural analgesia was used in 1670 patients, and intravenous morphine in 1026 patients. Patients with epidural analgesia experienced less pain both at rest and during mobilization. Insufficient treatment effects such as dose adjustments, orthostatism/leg weakness, and pruritus were more common in the epidural group. Respiratory depression and sedation/hallucinations/nightmares/confusion occurred more often in the intravenous group. Thoracic epidural catheters caused a lower incidence of motor blockade compared to lumbar catheter placements.

CONCLUSION

In a large patient population the use of epidural and intravenous postoperative analgesia was considered safe in surgical wards, and the incidence of adverse effects was low. Patients with epidural analgesia experienced overall less pain, while opioid related side-effects were more common with intravenous morphine analgesia.

Pain management after major orthopaedic surgery: current strategies and new concepts

Several recently developed analgesic techniques effectively control pain after major orthopaedic surgery. Neuraxial analgesia provided by epidural and spinal administration of local anesthetics and opioids provides the highest level of pain control; however, such therapy is highly invasive and labor intensive. Neuraxial analgesia is contraindicated in patients receiving low-molecular-weight heparin. Continuous plexus and peripheral neural blockades offer excellent analgesia without the side effects associated with neuraxial and parenteral opioids. Intravenous patient-controlled analgesia allows patients to titrate analgesics in amounts proportional to perceived pain stimulus and provide improved analgesic uniformity. Oral sustained-release opioids offer superior pain control and greater convenience than short-duration agents provide. Opioid dose requirements may be reduced by coadministration of COX-2-type nonsteroidal analgesics.

Comparison of patient-controlled epidural analgesia with and without background infusion after gastrectomy

To assess the analgesic efficacy and side effects of concurrent infusion in patient-controlled epidural analgesia (PCEA) after upper abdominal surgery, 40 patients undergoing elective gastrectomy under general anesthesia were allocated to two groups in this randomized, double-blind study: one received a 2.5-mL incremental bolus in a solution of 0.2% bupivacaine and 10 microg/mL fentanyl, and the other received the same bolus dose plus a 2.5-mL/h infusion of the same solution. The number of demands was smaller (P < 0.001) in the PCEA plus infusion group than in the PCEA alone group during the 48-h postoperative period. The average hourly fentanyl and bupivacaine doses were larger (P < 0.0001) in the PCEA plus infusion group than in the PCEA alone group. Visual analog scale pain scores on coughing in the PCEA plus infusion group were lower than in the PCEA alone group (P < 0.05). There was a greater incidence of pruritus in the PCEA plus infusion group (P < 0.05), but no serious side effects were observed in either group. In conclusion, a background infusion in PCEA with a mixture of fentanyl and bupivacaine decreases the incidence of postoperative pain and reduces the degree of pain associated with coughing without serious side effects after gastrectomy.

IMPLICATIONS

A background infusion in patient-controlled epidural analgesia with a mixture of fentanyl and bupivacaine decreased the incidence of postoperative pain and reduced the degree of the pain associated with coughing without serious side effects in this randomized, double-blind study after gastrectomy.

[Controlled analgesia in a burn patient: fentanyl sparing effect of clonidine]

OBJECTIVE

To determine the sparing effect of clonidine (C) on fentanyl (F) demand in burned patients under PCA.

STUDY DESIGN

Prospective, randomized, double blind study versus placebo.

PATIENTS

Twelve consecutive patients with mean burn surface area of 20 +/- 9%, studied between the third and the eighth day post-burn.

METHODS

F was delivered by a PCA pump (bolus: 1 mg.kg-1). In the morning, burn patients received additional F (5 mg.kg-1) before hydrotherapy. After randomisation, C or placebo (P) were alternatively infused over 24 hours. Demands for F during the morning, the afternoon and the evening were noted. Pain scores were measured on a visual analogic scale. In eight patients, plasma levels of F (pF) were iteratively measured. Heart rate, arterial pressure, respiratory rate and SpO2 were monitored.

RESULTS

Analgesic demands were 19.5/day under P and 9.5 under C (P < 0.0001). Pain reoccurred for pF of 4.1 under C vs 5.7 under P (P < 0.05) with same pain scores in the two groups. After a pain stimulus, pain scores were lower under F, despite lower pF (P < 0.05). Arterial pressure and heart rate were significantly lowered during the first hour of C infusion.

CONCLUSION

Doses of F and pF required to reach analgesia were very high. Adding C decreases by 50% the F demand and lowers pF. Minor haemodynamic effects were observed during the first hour of C infusion.

[Patient-controlled analgesia. Benefits, risks, methods of monitoring]

Patient-controlled analgesia refers to a relatively new approach to morphine delivery in which patients are allowed to self-administer small doses of an opioid, to achieve adequate relief of postoperative pain. The main benefit is to reduce fluctuations in opioid plasma concentrations. A matter for worry remains the occurrence of side effects, especially ventilatory depression. In order to guarantee the efficacy and safety of this technique, the education of patients and nurses is essential. Protocols are required, specifying the use of this technique (prescription, patient monitoring, treatment of side effects).

Intranasal absorption of oxymorphone

The nasal bioavailability of oxymorphone HCI was determined. Rats were surgically prepared to isolate the nasal cavity, into which a solution of oxymorphone was administered. A reference group of rats was administered oxymorphone HCl intravenously. Plasma oxymorphone concentrations were determined by HPLC. Nasal absorption was rapid, nasal bioavailability was 43%, and the iv and nasal elimination profiles were similar. Oxymorphone HCI appears to have the solubility, potency, and absorption properties required for efficient nasal delivery, which is an alternative to injections.

Patient-controlled epidural analgesia after caesarean section using meperidine

PURPOSE

To determine the effects of the addition of a background infusion to patient-controlled epidural analgesia (PCEA) using meperidine for analgesia after Caesarean section.

METHODS

In a randomized, double-blind study, we assigned 40 patients having elective Caesarean section to receive postoperative analgesia by patient-controlled epidural analgesia (PCEA) using meperidine 5 mg.ml-1 with (group Pi) or without (group Po) a background infusion of 10 mg.hr-l. The PCEA settings (20 mg bolus, 10 min lockout interval, four-hour maximum dose 150 mg) were otherwise identical. We compared pain at rest, pain on coughing, side effects, number of PCEA demands, drug consumption and patient satisfaction between groups in the first 24 hr after surgery.

RESULTS

Total consumption of meperidine was greater in group Pi (median 390 mg) than in group Po (median 240 mg; P = 0.017) and the number of PCEA demands was greater in group Po (median 12) than in group Pi (median 7.5; P = 0.012). Analgesia, side effects and patient satisfaction was similar between groups.

CONCLUSION

Addition of a background infusion to PCEA using meperidine after Caesarean section has no clinical benefit.

Postoperative analgesia with parenteral opioids: does continuous delivery utilizing a transdermal opioid preparation affect analgesic efficacy or patient safety?

STUDY OBJECTIVES

To compare, in patients who underwent major orthopedic surgical procedures, the efficacy of intravenous (IV) patient-controlled analgesia (PCA) with morphine combined with continuous administration of two doses of fentanyl or placebo via transdermal therapeutic system with fentanyl (TTSF) patches.

DESIGN

Randomized, double-blind, placebo-controlled study.

SETTING

University teaching hospital.

PATIENTS

62 patients aged 18 to 65 years, presenting for elective orthopedic surgery and general anesthesia.

INTERVENTIONS

Patients were randomized to one of three groups: group 1 received two placebo patches; group 2 received a 20 cm2 active patch delivering 50 micrograms/hr of fentanyl and a 30 cm2 placebo patch; group 3 received a 30 cm2 active patch delivering 75 micrograms/hr of fentanyl and a 20 cm2 placebo patch. All patches were placed approximately two hours prior to induction of general anesthesia. General anesthesia was induced with thiopental, intubation facilitated by the use of vecuronium or pancuronium, and anesthesia was maintained with isoflurane in an oxygen/nitrous oxide mixture (O2/N2O). Following surgery, IV morphine was provided using IV PCA with 1.5 mg of morphine with a 6-minute lockout and a 4-hour maximum dosage of 30 mg.

MEASUREMENTS AND MAIN RESULTS

The time and dosage of morphine administered was recorded. Vital signs, pain intensity at rest, level of sedation, and arterial oxygen saturation (SpO2) were measured at intervals throughout the 72-hour study period and at 6 and 12 hours following patch removal. The presence of side effects was noted. Visual analog pain scores throughout the 72 hours of the study were not significantly different among groups. Patients receiving active TTSF required less IV PCA morphine at all time intervals. However, total opioid consumption was comparable among groups. The incidence of side effects was similar in all groups.

CONCLUSIONS

There is no significant advantage to the routine use of continuous transdermal opioid delivery in patients receiving IV PCA after major orthopedic surgery.

Effect of varying intravenous patient-controlled analgesia dose and lockout interval while maintaining a constant hourly maximum dose

STUDY OBJECTIVE

To investigate the effect on the use of intravenous patient-controlled analgesia (PCA) of varying the dose (D) and lockout interval (LI) while keeping the hourly maximum dose constant.

DESIGN

Randomized, prospective study.

SETTING

Teaching hospital.

PATIENTS

75 patients scheduled to receive PCA morphine following abdominal surgery.

INTERVENTIONS

Postoperatively, patients were randomly assigned to receive PCA morphine with the following parameters: D = 1 mg, LI = 6 min (Group 1-6), D = 1.5 mg, LI = 9 min (Group 1.5-9), or D = 2 mg, LI = 12 min (Group 2-12), so that each group could receive a maximum hourly dose or 10 mg. Inadequate analgesia was managed by increasing the dose and lockout interval, while excessive sedation or respiratory rate less than 10 breaths/min resulted in decreasing the dose and lockout interval.

MEASUREMENTS AND MAIN RESULTS

Patients were assessed for pain [visual analog scale (VAS), verbal rating scale (VRS)] and side effects at 1, 2, 4, and 24 hours. The number of doses administered, missed attempts, and morphine used for the first 24 hours was recorded by automatic printout from the PCA machine. There was no difference in the total 24-hour morphine consumption, analgesia, or incidence of side effects among the three groups at any of the measurement times. Two patients, one each in the 1.5-9 and 2-12 groups, required naloxone for respiratory depression. The number of PCA injections, attempts, missed attempts, and the incidence of dosage adjustment were all significantly higher for the 1-6 group (p < 0.05).

CONCLUSION

The use of 1.0 mg with a 6-minute lockout may represent appropriate dose titration because this group obtained equivalent analgesia, morphine use, and side effects as the two larger dose and lockout groups. However, the increased number of PCA attempts and missed attempts may reflect lower satisfaction with PCA therapy.

Patient-controlled analgesia versus patient-controlled analgesia plus continuous infusion after hip replacement surgery

OBJECTIVE

To compare the efficacy and adverse effect profile of patient-controlled analgesia (PCA) versus PCA plus continuous infusion (PCACI) after hip replacement surgery.

DESIGN

Prospective, randomized, open pilot study.

SETTING

Large teaching institution.

PARTICIPANTS

Thirty-four patients undergoing hip replacement or revision of hip replacement surgery.

INTERVENTIONS

Patients were randomized to receive PCA morphine: 1 mg with 6-minute lockout, or PCACI, using the same dose, with a 0.5-1 mg/h continuous infusion. Pain intensity, sedation, narcotic use, injection/attempt ratio (I/A), and adverse effects were assessed.

RESULTS

No significant differences in pain intensity were identified. Morphine use was not different between groups: PCA 61.8 +/- 35.0 and PCACI 74.2 +/- 54.9 mg (p =0.394). A trend toward an increased 12-hour I/A ratio was evident in the PCACI group: PCA 0.73 +/- 0.18 and PCACI 0.86 +/- 0.17 (p =0.073). Patient-reported adverse effects, sedation, and inability to sleep secondary to pain occurred similarly. Eight of 18 PCACI patients required discontinuation of either the continuous infusion mode or of PCA therapy entirely secondary to adverse effects.

CONCLUSIONS

When compared with PCA therapy, PCACI was not associated with improved pain control and more patients receiving PCACI required discontinuation of therapy secondary to adverse effects.

Variation in opioid use during PCA in adolescents

The objective of this investigation was to determine if the variability in the use of opioids for pain following surgery is related to variability in blood concentration of opioids used for pain relief. We measured morphine use and morphine blood concentration in a group of otherwise healthy adolescent girls following spinal surgery. There was considerable variability in morphine use and morphine blood levels as indicated by a large range of values and a moderately large standard deviation. Morphine blood concentration correlated with morphine use. Neither morphine use nor morphine concentration correlated with pain scores. The data indicate that there is considerable variability among patients in the amount of opioid needed to achieve comfort and in the blood concentration associated with comfort. The cause of this variability does not appear to be related to metabolism of opioid, but may be related to psychological differences, differences in pain tolerance and threshold, or differences in the way patients use PCA.

The efficacy of adding a continuous intravenous morphine infusion to patient-controlled analgesia (PCA) in abdominal surgery

The effect of adding a continuous infusion of morphine 1 mg/hr to patient-controlled intravenous analgesia was studied in a randomized double-blind trial. Ninety-six patients scheduled for abdominal surgery were enrolled; 38 received PCA and continuous infusion (PCA + C), 45 received PCA alone and 13 were excluded because of protocol violations. PCA was delivered via an ABBOTT 4200 pump with settings of morphine 1 mg bolus and five-minute lockout in both groups. A separate pump delivered a continuous infusion of morphine 1 mg/ml (PCA + C) or 9% normal saline (PCA) at 1 ml/hr for three postoperative days. Pain was assessed by hourly verbal pain scores (VPS) and daily visual analog pain scores at rest and on movement (VAS(rest), VAS(move)). PCA delivered morphine and the demand to delivery ratio (D/D ratio) were used as indirect indicators of pain. These were assessed during daytime (0800-2200 hours), sleep (2200-0500 hours) and on first waking (0500-0800 hours). Patient demographics were similar. Patients receiving a continuous infusion had lower pain scores during the first 24 hours but not thereafter (VPS P = 0.04, VAS(move) P = 0.02). The PCA group delivered more PCA morphine during 0500-0800 hours and 0800-2200 hours on the first day only. There was no significant difference in the D/D ratio for any time period during the three days. Total morphine delivery was greater in the PCA + C group on the second and third postoperative days (P = 0.009 and P = 0.0001 respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Epidural sufentanil for postoperative patient-controlled analgesia (PCA) with or without background infusion: a double-blind comparison

To evaluate the usefulness of a concurrent infusion in patient-controlled epidural analgesia (PCEA), 40 patients scheduled for elective cesarean section under a combined spinal-epidural technique were assigned randomly in a double-blind fashion to receive sufentanil by PCEA with a concomitant infusion of either sufentanil or saline. The sufentanil 24-h consumption was significantly (P < 0.001) higher in those patients receiving the opioid-containing infusion (212.7 +/- 9.5 vs 128.4 +/- 10.8 micrograms, SEM). The number of additional demands and the quality of sleep did not differ between the two groups. The degree of sedation was significantly less pronounced in patients treated with incremental sufentanil doses only. The visual analog scale (VAS) pain scores at rest were identical in both groups except at 6 h (2.5 +/- 0.4 vs 3.7 +/- 0.3, in favor of the patients treated with the sufentanil background infusion). We conclude that, except for a lower pain score during the initial hours, a background infusion in PCEA with sufentanil does not offer major advantages in terms of sleep quality or sufentanil consumption. Side effects may be more pronounced owing to increased drug administration.

Patient-controlled analgesia: a comparison of dosing regimens for acute postsurgical pain

This study compares several dosing regimens for patient-controlled analgesia (PCA) in the management of acute maxillofacial surgical pain. The dosing methods differed by presence or absence of an active drug (morphine [MS] vs saline), presence of a baseline infusion, and dose of drug delivered. Sixty-eight patients were enrolled in this prospective, randomized, double-blind, placebo-controlled trial that lasted 24 hours. The study was completed in two separate parts, each of which involved randomization of patients into four groups (part I) or three groups (part II). No significant differences were noted in pain scores in the preoperative, immediate postoperative, or 4-, 8-, 12-, or 24-hour periods among any of the groups, including the saline-only control groups; in either part I or part II of the study. Significant differences (P < .01), however, were noted in nausea and vomiting scores. Fifty percent (50%) of patients receiving MS vomited, while no patients in the saline groups vomited. This study calls into question the usefulness of PCA with MS in maxillofacial surgery patients. Pain control was questionable at best, and the rate of emesis was unacceptably high in patients with potentially compromised airways. Further research is required to determine if other analgesics provide better pain control with less nausea in the PCA system or if antiemetics can effectively be used to lower the incidence of nausea and vomiting.

Respiratory depression associated with patient-controlled analgesia: a review of eight cases

Patient-controlled iv delivery of opioids for postoperative pain management is a popular alternative to the traditional im route of administration. However, occasional patients receiving opioids in this manner develop severe respiratory depression. The purpose of this paper is to determine the incidence of, and factors contributing to, the development of this complication. To do this, the Office of Medical Quality Improvement retrospectively searched for reports of respiratory depression in a database compiled from the charts of approximately 1600 patients who had received PCA at the University of Alberta Hospitals in 1992. Eight cases of serious respiratory depression were detected. Factors associated with the occurrence of respiratory depression included the concurrent use of a background infusion, advanced age, concomitant administration of sedative/hypnotic medications, and pre-existing sleep apnoea syndrome. No cases were attributed to operator error or equipment malfunction. In conclusion, the risk of respiratory depression with patient-controlled opioid administration is similar to that observed when opioids are delivered by the traditional im or spinal routes. The safe and effective use of patient-controlled analgesia depends upon knowledgeable medical and nursing staff, clearly defined nursing policy and procedures, and frequent patient follow-up.

[Patient-controlled analgesia: a study of fentanyl requirements in burnt patients during the acute phase]

This study assessed over the first post-burn week the patients' demands for opiates delivered with a PCA device, changes in opioid delivery along the day, especially during painful events and the incidence of side effects. Twenty-two patients (8 women, 14 men), mean age 33 years (+/- 12 SD), mean BSA 21% (+/- 13 SD), mean deep dermal burn 12% (+/- 11 SD) were included. Fentanyl was delivered by i.v. route using a PCA device during the first 6 days post burn. Bolus dose was fixed at 1 microgram.kg-1, lock-out time at 30 min and the 4 h limit dose at 7 micrograms.kg-1. The following data were collected every day: satisfied and non-satisfied demands, total daily dose, demands during and after dressing change period (4 h), during afternoon (10 h) and overnight periods (10 h). Heart rate (HR), respiratory rate (RR), blood pressure (BP), Paco2 and Spo2 were also monitored. The mean total daily demands were similar from D1 to D6 (28 +/- 7). Around 7 demands/day were not satisfied. The mean total daily satisfied demands were also the same: 21 +/- 5. Individual demands were over a wide range (minimum: 15, maximum: 41 demands/day for total demands and 13 and 34 respectively for the satisfied ones). Mean fentanyl delivery was 1.7 +/- 0.1 microgram.kg-1.h-1 during dressing period, 0.9 +/- 0.3 microgram.kg-1.h-1 during afternoon period (10 h) and 0.5 +/- 0.2 during overnight period (10 h). No-satisfied demands were around 4 boluses during dressing change period, 2 boluses during afternoon period, and one bolus during overnight period.(ABSTRACT TRUNCATED AT 250 WORDS)

[Introducing patient-controlled analgesia in a private hospital]

Patient controlled analgesia (PCA) is now a well recognized technique for postoperative analgesia. This study reports an experience of 24 months with 768 patients in a French private hospital. The first step was to train the team for this new technique. The second step was to agree on standards of prescription and safety monitoring rules (respiratory rate plus sedation score), as well as on the selection of patients. Analgesia was obtained with self administrated bolus plus a constant infusion (0.5 milligram per hour) of morphine in all patients, and in some with an addition of paracetamol or ketoprofene for a sparing effect on morphine consumption. All patients were returned to their ward, after an initial titration of pain treatment in the recovery room. No major problems occurred during the study period. In 13 patients the respiratory rate decreased to or under 10 c.min-1 without increased sedation and for safety reasons, the PCA was discontinued. PCA is now routinely used postoperatively for a majority of painful procedures in our institution.

Comparison of hydromorphone continuous subcutaneous infusion and basal rate subcutaneous infusion plus PCA in cancer pain: a pilot study

In this pilot randomized, double-blind, cross-over study, the effectiveness and safety of hydromorphone administration by continuous subcutaneous (s.c.) infusion (mode A) and by continuous basal rate s.c. infusion + PCA (mode B) were compared in 8 cancer patients. Patients experimented with each infusion mode during 48 h. Statistical analysis was performed on data collected in 7 patients during 36 h from 22:00 h on day 1 to 10:00 h on day 3 and from 22:00 h on day 3 to 10:00 h on day 5. Mean hydromorphone dose +/- S.D. was 56.6 +/- 30.1 and 40.4 +/- 24.5 mg/36 h for modes A and B, respectively. There was no statistically significant difference observed in mean pain intensity, but the absence of significant difference may be related to the small sample size and high individual variability. Both methods provided adequate overall pain control in most patients. However, a large interindividual variation was detected. Indeed, some patients reported in the subjective questionnaire that they felt marked discomfort during hydromorphone administration with mode B. Only 2 patients chose mode B at the end of the study, but it was interesting to note that those 2 patients were the youngest of the group. This study demonstrated the effectiveness and safety of both modes of hydromorphone administration. The data suggest that it may be possible to identify particular cancer patients which can really benefit from an association of a basal rate infusion and PCA for opiate administration.

Background infusion with patient-controlled analgesia: effect on postoperative oxyhaemoglobin saturation and pain control

The aim of this study was to determine whether the addition of a background infusion (BI) to patient-controlled analgesia (PCA) would lead to significantly improved pain control or poorer oxyhaemoglobin saturation (SpO2) after gynaecological surgery. Sixty-two patients were studied for 24 hours postoperatively; pain scores and morphine dose were recorded hourly, SpO2 was recorded every 10 seconds. Administration of the BI resulted in a significant increase in total morphine dose received although there was no difference in the severity of postoperative desaturation between the therapies. Despite the increased morphine dose pain scores also were similar in the two groups. Addition of a BI at 1 mg/hr did not confer any advantage over PCA alone and is not recommended when PCA is used in this patient group.

Pharmacological management of pain in children

This article examines the use of analgesics and psychopharmacological adjuvants in children experiencing pain. Peripheral analgesics are effective for mild to moderate pain. Narcotics are effective but may produce dependence and tolerance as well as untoward side effects. Major tranquilizers, minor tranquilizers, tricyclic antidepressants, and stimulants have all been used as adjuvants in pain management. Major tranquilizers are now discouraged because of potential serious adverse effects. Benzodiazepines are relatively safe and decrease anxiety accompanying pain. Tricyclics may be used with caution. Stimulants have received little attention but may be useful in treating both pain and depression in the physically ill.

The effect of fentanyl administered epidurally by patient-controlled analgesia, continuous infusion, or a combined technique of oxyhaemoglobin saturation after abdominal surgery

The aims of this study were to determine the effect of three different modes of epidural administration of fentanyl on oxyhaemoglobin saturation and pain control. Forty-three patients undergoing elective abdominal surgery were randomly allocated to the following groups: (1) continuous infusion of fentanyl at a rate of 50 micrograms.h-1 with additional epidural boluses (25 micrograms) as required; (2) patient-controlled analgesia using a 25 microgram epidural bolus of fentanyl with a 15 min lock-out period; (3) a combination of patient-controlled analgesia and continuous infusion. Oxyhaemoglobin saturation was measured by continuous computerised pulse oximetry for 48 h after operation together with pain and sedation scores. In the first 24 h after surgery patients in the continuous infusion group spent a significantly greater proportion of time below oxygen saturations of 94% and 85% than those in the other two groups. On day 2 all oxygen saturation measurements were worse than during day 1, but differences between groups were not significant. Those patients receiving patient-controlled analgesia required significantly less fentanyl than patients in either of the other groups (p < 0.05). However, the mean pain and sedation scores did not differ significantly between the three treatment groups. There was no association between total fentanyl dose and oxygen saturation values. Overall, self-administered fentanyl appeared to cause less oxyhaemoglobin desaturation than nurse-administered analgesia without any loss of analgesic effect.