Patient-controlled modalities for acute postoperative pain management

Comparison of different sufentanil-tramadol combinations for pain relief within the first 24 hours after cesarean section: a retrospective study

Introduction

Postcesarean section pain management is important for both the mother and the newborn. This study compared the analgesic effects and incidence of adverse events associated with intravenous patient-controlled analgesia (iv-PCA), using different sufentanil–tramadol combinations for postoperative pain control.

Methods

Parturients (n=5,794) who had been scheduled for cesarean section under neuraxial anesthesia and had received iv-PCA between September 2013 and March 2017 were retrospectively analyzed. These patients were assigned to three groups, based on different sufentanil–tramadol combinations: ST1 (n=1,347), ST2 (n=2,401), and ST3 (n=2,046). The analgesic efficacy, total drug consumption, and incidence of adverse effects within 24 hours after surgery were compared among the three groups.

Results

The ST3 group had lower visual analog scale pain scores at rest and with movement at all time points during the first 24 hours postoperatively than the other two groups (P<0.01, Bonferroni corrected). The sufentanil dosage administered to the ST3 group was lower, and the tramadol dosage was higher than those administered to the other groups within 24 hours after surgery (P<0.01, Bonferroni corrected). Moreover, all parturients scored 2 points on the Ramsay sedation scale. Adverse reactions such as pruritus and respiratory depression were not observed in any group. No significant differences were noted in the incidence of nausea/vomiting, abdominal distension, and dizziness among the three groups (P>0.05).

Conclusion

The visual analog scale scores for postoperative pain decreased as the concentrations of sufentanil and tramadol administered in iv-PCA moderately increased over 24 hours after surgery. This analgesic strategy resulted in a significant reduction in the total sufentanil requirement without increasing the incidence of adverse effects.

Indirect treatment comparison of two non-invasive patient-controlled analgesia treatments for acute post-operative pain management

OBJECTIVES

To evaluate the relative clinical efficacy, safety, and tolerability associated with two non-invasive patient-controlled analgesia (PCA) treatments, sufentanil sublingual tablet system (SSTS) and fentanyl iontophoretic patient-controlled transdermal system (PCTS). These two treatments have recently been approved in the EU for the management of acute moderate-to-severe post-operative pain in adult patients.

METHODS

As no head-to-head trials comparing SSTS and PCTS currently exist, indirect treatment comparison (ITC) analyses were conducted to evaluate SSTS or PCTS versus intravenous (IV) morphine PCA.

RESULTS

Five studies, four assessing PCTS and one assessing SSTS, were included in this analysis. SSTS had statistical or numerical advantages over PCTS for both patient global assessment (PGA) and healthcare professional global assessment (HPGA) outcomes at all time points investigated. SSTS was also associated with greater patient ease of use (weighted mean difference [WMD]: 0.13; 95% confidence interval [CI]: -0.02-0.28) and a higher patient satisfaction score (WMD: 0.31; 95% CI: 0.05-0.57; p = .019) compared with PCTS. In terms of tolerability, all-cause withdrawals from treatment were reported to be less likely with SSTS (risk ratio: 0.65; 95% CI: 0.42-1.02). No significant differences were observed between SSTS and PCTS in terms of safety and adverse events.

CONCLUSIONS

In the absence of direct head-to-head data, the combination of promising phase III trial results compared to IV morphine PCA, a SLR comparison against other opioid treatments, and the results of this exploratory analysis present a strong rationale in support of SSTS as a key option for management of post-operative pain.

Analgesic Effects of Preincision Ketamine on Postspinal Caesarean Delivery in Uganda's Tertiary Hospital: A Randomized Clinical Trial

Background. Good postoperative analgesic management improves maternal satisfaction and care of the neonate. Postoperative pain management is a challenge in Mulago Hospital, yet ketamine is accessible and has proven benefit. We determined ketamine's postoperative analgesic effects. Materials and Methods. We did an RCT among consenting parturients that were randomized to receive either intravenous ketamine (0.25 mg/kg) or placebo after spinal anesthetic. Pain was assessed every 30 mins up to 24 hours postoperatively using the numerical rating scale. The first complaint of pain requiring treatment was noted as “time to first breakthrough pain.” Results. We screened 100 patients and recruited 88 that were randomized into two arms of 44 patients that received either ketamine or placebo. Ketamine group had 30-minute longer time to first breakthrough pain and lower 24-hour pain scores. Postoperative diclofenac consumption was lesser in the ketamine group compared to placebo and Kaplan-Meier graphs showed a higher probability of experiencing breakthrough pain earlier in the placebo group. Conclusion. Preincision intravenous ketamine (0.25 mg/kg) offered 30-minute prolongation to postoperative analgesia requirement with reduced 24-hour pain scores. We recommend larger studies to explore this benefit. This trial is registered with Pan African Clinical Trial Registry number PACTR201404000807178.

Meta-Analysis of the Ease of Care From the Nurses' Perspective Comparing Fentanyl Iontophoretic Transdermal System (ITS) Vs Morphine Intravenous Patient-Controlled Analgesia (IV PCA) in Postoperative Pain Management

PURPOSE

The aim of this meta-analysis was to compare the ease of care (EOC) of fentanyl iontophoretic transdermal system (ITS) vs the morphine intravenous patient-controlled analgesia (IV PCA) as assessed by the nurse.

DESIGN

Meta-analysis of three phase 3B randomized active-comparator trials.

METHODS

This meta-analysis according to Cochrane's approach assessed EOC using a validated nurse questionnaire (22 items grouped into three subscales, which include time efficiency, convenience, and satisfaction) in adult patients treated with fentanyl ITS or morphine IV PCA for postoperative pain management. The weighted mean difference (WMD) between treatments was calculated.

FINDING

EOC analyses were based on responses to questionnaires from 848 (fentanyl ITS) and 761 (morphine IV PCA) nurses. Fentanyl ITS was reported to provide significant advantages compared with morphine IV PCA in terms of nurses' overall EOC (WMD = -0.57, P < .0001) and each of the subscales: time efficiency (WMD = -0.58, P < .0001), convenience (WMD = -0.57, P < .0001), and satisfaction (WMD = -0.47, P < .0001).

CONCLUSIONS

In this meta-analysis, fentanyl ITS is associated with a superior EOC profile from the nurses' perspective than morphine IV PCA.

Meta-Analysis of the Ease of Care From a Patients' Perspective Comparing Fentanyl Iontophoretic Transdermal System Versus Morphine Intravenous Patient-Controlled Analgesia in Postoperative Pain Management

PURPOSE

The purpose of this meta-analysis was to evaluate patients' assessment of fentanyl iontophoretic transdermal system (ITS) and morphine intravenous patient-controlled analgesia (IV PCA) ease of care (EOC) using a validated patient EOC questionnaire. Fentanyl ITS is a preprogrammed, needle-free PCA system used for the management of acute pain in postoperative patients.

METHODS

This meta-analysis assessed the patient EOC of fentanyl ITS and morphine IV PCA using data from three randomized, active-comparator trials in adult postoperative patients with moderate-to-severe pain. All three studies utilized a validated patient EOC questionnaire which consists of 23 items grouped into seven subscales (confidence with device, comfort with device, movement, dosing confidence, pain control, knowledge/understanding, and satisfaction). Each item is scored on a six-point Likert scale. The weighted mean difference between treatments was calculated for the overall EOC and for each of the seven subscales.

RESULTS

The EOC analyses were based on responses to questionnaires from 1,943 patients treated with either fentanyl ITS (n = 961) or morphine IV PCA (n = 982). There was a statistically significant advantage in favor of fentanyl ITS over morphine IV PCA in terms of overall EOC (weighted mean difference = 0.28; 95% confidence interval (0.22 to 0.34); P < 0.0001). Five of the seven subscales (confidence with device, comfort with device, movement, dosing confidence, and knowledge/understanding) on the patient EOC questionnaire showed a statistically significant advantage for fentanyl ITS versus morphine IV PCA. The two subscales that did not show any difference were pain control (P = 0.7303) and satisfaction (0.0561).

CONCLUSION

In this meta-analysis, fentanyl ITS is associated with some advantages in terms of an EOC profile from a patients' perspective when compared with morphine IV PCA.

Ease-of-care from the physical therapists’ perspective comparing fentanyl iontophoretic transdermal system versus morphine intravenous patient-controlled analgesia in postoperative pain management

Aim: To compare the ease-of-care (EOC) examining time efficiency, convenience and satisfaction of fentanyl iontophoretic transdermal system ([ITS] IONSYS®) and morphine intravenous patient-controlled analgesia (iv. PCA) in postoperative pain management using a validated physical therapist (PT) EOC questionnaire. Materials & methods: This meta-analysis assessed EOC of fentanyl ITS versus morphine iv. PCA using data from two randomized, active-comparator studies (fentanyl ITS: n = 720 and morphine iv. PCA: n = 739) which used the PT EOC questionnaire (22 items grouped into three subscales; time efficiency, convenience and satisfaction). Each item was scored on a 6-point Likert scale. For time efficiency, PT whose average scores were ≤2 on all items of the time efficiency and convenience subscales or ≥4 on both satisfaction items were considered responders. Results: There were EOC questionnaires from 264 (fentanyl ITS) and 254 (morphine iv. PCA) PTs. There were significantly greater proportions of PTs classified as responders for fentanyl ITS than morphine iv. PCA for overall EOC (81.0 vs 55.7%, respectively), time efficiency (83.1 vs 59.5%, respectively), convenience (87.4 vs 72.0%, respectively) and satisfaction (51.9 vs 30.0%, respectively), all p < 0.0001. Conclusion: In this meta-analysis, fentanyl ITS is associated with a superior EOC profile (overall, time efficiency, convenience and satisfaction) from the PTs’ perspective when compared with morphine iv. PCA.

Do Elderly Patients Use Patient-Controlled Analgesia Medication Delivery Systems Correctly?

BACKGROUND

Although prior studies have shown patient-controlled analgesia (PCA) to be appropriate for use by children and adults, no studies have specifically evaluated the ability of elderly patients to use the technology correctly.

PURPOSE

To determine whether elderly, postoperative patients can properly use PCA devices.

METHODS

Using a descriptive study design, a convenience sample of elderly, postoperative orthopedic patients was observed while using a PCA device and surveyed about the proper use of the device. Participants were observed and surveyed 12 to 20 hours after admission to the postoperative patient care unit. Frequency and amount of analgesic medication administration over the postoperative time period were also recorded. Data were summarized with descriptive statistics and multiple regression analysis was used to determine whether confounding variables explained problems using the PCA device correctly.

RESULTS

A total of 58 orthopedic patients were studied during the first day after surgery. Patients had used the PCA device for 16.6 ± 3.0 (mean ±SD) hours at the time of the observation and survey. Virtually all patients correctly identified and depressed the PCA activation button when instructed, knew when to use the PCA device, and who was allowed to depress the PCA button. Slightly more than half of the patients (57%) correctly identified how often they could have PCA medication, with 38% not sure of PCA medication frequency. The PCA medication was requested an average of 23.3 ± 52.7 times during the study period. The majority of the patients (86%) requested PCA medication less than 25% of the times that they could receive PCA medication. All patients in the study had PCA devices programmed to deliver up to 5 doses per hour of PCA medication, yet an average of 11.2 ± 10.8 doses of PCA medication were actually delivered during the entire study period (average 16.6 hours). Average doses of fentanyl and morphine sulfate received by patients were 13.5 μg/hour and 1.0 mg/hour, respectively.

CONCLUSION

Elderly patients were very knowledgeable about how to use the PCA device but not about how often they could receive PCA medication. This lack of knowledge may have influenced how often they requested pain medication, because almost 90% of patients received less than 25% of the PCA allowable medication dose. This low usage of PCA medication delivery calls into question the cost-effectiveness of this method of medication delivery for the elderly. Additional studies are needed to verify these findings in other elderly patients.

Anaesthesia and pancreatic surgery: Techniques, clinical practice and pain management

Pancreatic cancer continues to pose a major public health concern. The incidence of the disease is nearly equivalent to the death rate associated with the diagnosis of pancreatic cancer. Thus, there exists a need for continued improvement in the diagnostic, therapeutic and palliative care of these patients. There have been significant advances made over the years in the areas of critical care, anesthesia, and surgical technique, which have led to improved mortality rates and survival after resection for pancreatic cancer. Resections are performed with the goals of negative margins and minimal blood loss and referral to high-volume centers and surgeons is encouraged. However, 5-year survival rate after curative resection still remains at less than 20%. Perioperative management of pancreatic and periampullary cancer poses a considerable challenge to the pancreatic surgeon, anesthesiologist and the intensive care team. Major morbidity is often secondary to pancreatic anastomotic leakage and fistula or infection. The anesthesiologist plays a crucial role in the perioperative management of such patients and in the pain control. Pancreatic ductal adenocarcinoma has a high rate of neural invasion (80%-100%) and can be associated with moderate to severe pain. In the recent past, new information has emerged on many issues including preoperative biliary drainage, nutritional support, cardiovascular assessment, perioperative fluid therapy and hemodynamic optimization. Careful patient selection and appropriate preoperative evaluation can greatly contribute to a favorable outcome after major pancreatic resections.

Current and developing methods of patient-controlled analgesia

Moderate-to-severe acute postoperative pain is commonly controlled with opioids administered via programmable intravenous (IV) patient-controlled analgesia (PCA) infusion pumps. Intravenously administered opioids provide effective relief of postoperative pain, and IV PCA enables patients to control their level of analgesia, which has advantages over nurse-administered approaches, including more satisfied patients and improved pain relief. Unfortunately, commonly used opioid analgesics can cause significant adverse effects. Furthermore, IV PCA has drawbacks, such as device programming errors, system errors, medication errors, limitations in patient mobility, and potential for IV tubing kinks, clogging, and transmission of infection. The IV route of administration is also characterized by a rapid, high peak in analgesic drug concentration followed by rapidly decreasing concentrations. Consequently, respiratory depression, excessive sedation, and inadequate pain control can occur. Furthermore, the technical assembly of an infusion pump is often complex and time-consuming. PCA modalities that incorporate superior opioid analgesics, such as sufentanil, and novel noninvasive routes of administration offer great promise for enhancing the patient and caregiver experience with the use of postoperative PCA.

Efficacy and safety of fentanyl HCl iontophoretic transdermal system compared with morphine intravenous patient-controlled analgesia for postoperative pain management for patient subgroups

BACKGROUND AND OBJECTIVE

Inadequate postoperative pain control remains a problem for many patients undergoing surgery. This study presents subgroup analyses from a large, randomized, multicentre, European study comparing the efficacy and safety of the fentanyl HCl iontophoretic transdermal system and morphine intravenous patient-controlled analgesia for postoperative pain management.

METHODS

The efficacy and safety of the fentanyl iontophoretic transdermal system and morphine intravenous patient-controlled analgesia were evaluated for patients divided by surgery type, sex, American Society of Anesthesiologists physical status and type of anaesthesia used during surgery. Efficacy measures included a patient global assessment of the method of pain control (a rating of 'good' or 'excellent' was considered as a success rating) and mean last pain intensity scores in the first 24 h. Discontinuation rates and the incidence of adverse events were also evaluated.

RESULTS

Numerically similar percentages of patients in most subgroups reported success on the last patient global assessment in the first 24 h for both the fentanyl iontophoretic transdermal system and morphine intravenous patient-controlled analgesia. Similar percentages of investigators reported success ratings on the investigator global assessment at the last assessment for both treatment groups regardless of surgery type, except for the knee surgery subgroup (fentanyl iontophoretic transdermal system, 75%; morphine intravenous patient-controlled analgesia, 95%). Mean last pain intensity scores in the first 24 h after surgery were similar in all subgroups. Rates of patient withdrawals and the incidence of adverse events were generally similar between treatment groups in the patient subgroups.

CONCLUSION

The fentanyl iontophoretic transdermal system and morphine intravenous patient-controlled analgesia are comparably well tolerated and effective methods of pain control, regardless of sex, American Society of Anesthesiologists physical status or the type of anaesthesia used for surgery, and following most surgery types.

Preoperative housing in an enriched environment significantly reduces the duration of post-operative pain in a rat model of knee inflammation

The influence of the environment on clinical post-operative pain received recently more attention in human. A very common paradigm in experimental pain research to model the effect of housing conditions is the enriched environment (EE). During EE-housing, rats are housed in a large cage (i.e. social stimulation), usually containing additional tools like running wheels (i.e. physical stimulation). Interestingly, only postsurgical housing effect on post-operative pain was developed during clinical and experimental studies while little is known on the influence of preoperative housing. In this study, our aim was to investigate the influence of housing conditions prior to an operation on the development of post-operative pain, using a rat model of carrageenan-induced inflammatory pain. Four housing conditions were used: a 3-week pre-housing in standard conditions (S-) followed by a post-housing in an EE; a 3-week pre-housing in EE followed by a post-operation S-housing; a pre- and post-housing in EE; a pre- and post-S-housing. The development of mechanical allodynia was assessed by the means of the von Frey test, preoperatively and at day post-operative (DPO) 1, 3, 7, 10, 14, 17, 21, 24 and 28. Our results show that a 3-week preoperative exposure to EE leads to a significant reduction in the duration of the carrageenan-induced mechanical allodynia, comparable with a post-operative exposure to EE. Strikingly, when rats were housed in EE prior to as well as after the carrageenan injection into the knee, mechanical allodynia lasted only 2 weeks, as compared to 4 weeks in S-housed rats.

Chronic pain alters drug self-administration: implications for addiction and pain mechanisms

This review article focuses on the impact that the presence of pain has on drug self-administration in rodents, and the potential for using self-administration to study both addiction and pain, as well as their interaction. The literature on the effects of noxious input to the brain on both spinal and supraspinal neuronal activity is reviewed as well as the evidence that human and rodent neurobiology is affected similarly by noxious stimulation. The convergence of peripheral input to somatosensory systems with limbic forebrain structures is briefly discussed in the context of how the activity of one system may influence activity within the other system. Finally, the literature on how pain influences drug-seeking behaviors in rodents is reviewed, with a final discussion of how these techniques might be able to contribute to the development of novel analgesic treatments that minimize addiction and tolerance.

Pharmacotherapy for acute pain: implications for practice

Effective treatment of perioperative acute pain requires that information about the patient's goals for pain relief, previous history with analgesics, and type of surgical procedure is used to guide decisions about analgesic regimens. Analgesics are selected based on the location of surgery, degree of anticipated pain, and patient characteristics (such as comorbidities), and routes of administration and dosing schedules are determined to maximize the effectiveness and safety of analgesia while minimizing the potential for adverse events. Pain management therapy is then extended into the postsurgical phase of recovery. To accomplish this, nurses must have a thorough understanding of the pharmacology of analgesics. This article provides useful information for commonly used analgesics, primarily nonsteroidal antiinflammatory drugs (NSAIDs), opioids, and local anesthetics for control of acute postoperative pain.

Pharmacotherapy for acute pain: implications for practice

Effective treatment of perioperative acute pain requires that information about the patient's goals for pain relief, previous history with analgesics, and type of surgical procedure is used to guide decisions about analgesic regimens. Analgesics are selected based on the location of surgery, degree of anticipated pain, and patient characteristics such as comorbidities, and routes of administration and dosing schedules are determined to maximize the effectiveness and safety of analgesia, while minimizing the potential for adverse events. Pain management therapy is then extended into the postsurgical phase of recovery. To accomplish this, nurses must have a thorough understanding of the pharmacology of analgesics. This article provides useful information for commonly used analgesics, primarily nonsteroidal antiinflammatory drugs (NSAIDs), opioids, and local anesthetics for control of acute postoperative pain.

Patient-controlled analgesia: patient and nurse satisfaction with intravenous delivery systems and expected satisfaction with transdermal delivery systems

OBJECTIVE

To compare patient and nurse satisfaction with intravenous patient-controlled analgesia (IV-PCA) to their prospective satisfaction with patient-controlled transdermal delivery system (PCTS) technology.

METHODS

Nationwide samples of 301 nurses (200 medical-surgical, 101 post-anesthesia care units) and 500 surgery patients (192 abdominal, 119 gynecological, 189 orthopedic) completed self-administered, Internet-based questionnaires. Respondents indicated satisfaction with attributes of IV-PCA and, after reading a description of PCTS, indicated prospective satisfaction with comparable attributes. Within patient and nurse samples, half rated IV-PCA first (and later re-rated overall satisfaction) and half rated PCTS first. Paired comparison t-tests were used to determine significant differences in satisfaction for IV-PCA and PCTS attributes.

RESULTS

Nurses reported significantly higher satisfaction with PCTS for patient and nurse ease of use, safety, and tolerability (p < 0.001 for all); and higher satisfaction with IV-PCA for the ability to vary drugs (p < 0.001) and doses (p < 0.001), deliver basal doses (p < 0.001), and dose tracking accessibility (p = 0.003) and quality (p = 0.002). Patients reported significantly higher satisfaction with PCTS for pain relief (p < 0.001), safety (p = 0.027), self-control (p < 0.001), and patient (p < 0.001) and nurse ease of use (p < 0.001); and higher satisfaction with IV-PCA for correct set-up and programming (p = 0.002). Overall satisfaction did not differ significantly among nurses, but among patients satisfaction with IV-PCA declined after considering PCTS (p < 0.001). Nurses placed greater importance on safety to their overall satisfaction than patients did.

LIMITATIONS

Only respondents with Internet access were included. PCTS satisfaction is hypothetical and may not reflect true product satisfaction.

CONCLUSION

PCTS is a novel delivery system for postoperative pain and has the potential to improve patient and nurse satisfaction over IV-PCA.

Rhythmic pattern in pain and their chronotherapy

Pain control is one of the most important therapeutic priorities; nonetheless, inadequate pain relief remains a significant health care issue. Thus, it is important to determine whether the analgesic effect can be improved by using the chronopharmacological approach. This paper reviews the data on the rhythmic patterns in pain level and their chronotherapy. It underlines the major issues and problems related to the development of chronotherapeutic strategies, and it examines emerging aspects of new drug-delivery systems for achieving such.

Adverse events involving intravenous patient-controlled analgesia

PURPOSE

This article systematically characterizes aspects of all Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) reports associated with i.v. patient-controlled analgesia (PCA) postoperative use during a two-year index period.

METHODS

Intravenous PCA represents a well-accepted and satisfactory means of acute pain treatment; case reports and large case series have described the occurrence of i.v. PCA-related adverse drug events (ADEs). MAUDE data files were downloaded, and all records pertaining to i.v. PCA devices were extracted for the two-year period from January 1, 2002, through December 31, 2003. Medical device events were categorized by their reported cause, including patient-related event, device safety event, operator error, and adverse reactions to opioids. Because there was not sufficient information to grade the certainty of each reported cause, all reported causes were graded "possible," except for device safety events that were confirmed on inspection by the manufacturer.

RESULTS

There were 2009 individual i.v. PCA-related MAUDE medical device events reported during the two-year period. Of these events, 1590 (79.1%) were classified as possible device safety events, 131 (6.5%) as possible operator error, 25 (1.2%) as possible adverse reactions to opioids, 12 (0.6%) as possible patient-related events, and 235 (11.7%) as indeterminate.

CONCLUSION

Manufacturer-confirmed device malfunction was a major cause of reported ADE with i.v. PCA infusion pumps while operator errors were more likely to be associated with more serious adverse outcomes than device safety problems. To reduce the incidence of these problems, potential vulnerabilities in the design and manufacture of i.v. PCA pumps must be identified and addressed.

Fentanyl HCl patient-controlled iontophoretic transdermal system for the management of acute postoperative pain

OBJECTIVE

To summarize the pharmaceutics, pharmacokinetics, development, and clinical application of IONSYS, the fentanyl HCl patient-controlled iontophoretic transdermal system for the management of acute postoperative pain.

DATA SOURCES

Clinical literature including both primary sources and review articles was accessed through a search of the MEDLINE databases (1980-October 2006). Key search terms included cutaneous analgesia, fentanyl, IONSYS, opioid, postoperative pain, and patient-controlled analgesia (PCA). Additional clinical trial and drug data were supplied by the manufacturer, the ALZA Corporation.

STUDY SELECTION AND DATA EXTRACTION

Review articles, abstracts, and clinical studies related to patient-controlled iontophoretic transdermal fentanyl and postoperative pain management were analyzed. An evaluation of the research exploring IONSYS for the management of acute postoperative pain was conducted. Relevant information was then selected and is provided in this article.

DATA SYNTHESIS

IONSYS is the first iontophoretic transdermal drug delivery system that utilizes low-level electrical energy to actively transport ionized fentanyl HCl through intact skin. Research has revealed that use of IONSYS for patients with acute postoperative pain is safe, effective, and well tolerated. Phase I-III trials have demonstrated an appropriate dosing range leading to effective analgesia, with minimal adverse effects. The analgesia provided by this system was found to be superior to that of analgesia placebo and equivalent to that of an intravenous morphine PCA.

CONCLUSIONS

Data from clinical trials indicated that IONSYS is successful in controlling acute postoperative pain that circumvents the limitations of intravenous patient-controlled analgesia. The use of this system may serve as an alternative modality for the management of acute pain without increasing such adverse effects as bleeding, intravenous catheter infiltration, or manual pump malfunction.