Patient-controlled Analgesia Machine Research Articles

Efficacy of Erector Spinae Plane Block on Postoperative Analgesia for Patients Undergoing Metabolic Bariatric Surgery: A Randomized Controlled Trial.

Metabolic bariatric surgery (MBS) advocates multimodal analgesia, discouraging opioid use to minimize side effects, such as nausea and vomiting, during postoperative pain management for quicker recovery. Combining erector spinae plane block (ESPB) with multimodal analgesia aims to reduce opioid consumption, improving postoperative recovery. This study aimed to compare morphine consumption between patients with severe obesity undergoing laparoscopic MBS with and without ESPB. This study enrolled 91 patients with severe obesity who underwent laparoscopic MBS involving either sleeve gastrectomy or Roux-en-Y gastric bypass. Of these, 63 patients were included in this study. The participants were randomly allocated to either the intervention group, which received an ESPB before the standard anesthesia protocol, or the control group, which did not receive pre-anesthesia block. The primary outcome measured was 24-h morphine consumption via a patient-controlled analgesia machine. Secondary outcomes included patients' satisfaction, postoperative numerical rating score, changes over time, and quality of recovery (QoR) using the Thai QoR-35 score. We found no statistically significant difference in morphine consumption between the intervention group and the control group. Furthermore, our analysis revealed no significant between-group differences in patient satisfaction, postoperative numeric rating score, or QoR across all five aspects evaluated using the Thai QoR-35 score. ESPB did not reduce morphine consumption or QoR following laparoscopic MBS. Further studies are required to confirm and identify the reasons for the ineffectiveness of ESPB.

A Retrospective Examination of Home PCA Use and Parental Satisfaction With Pediatric Palliative Care Patients.

Home Patient-Controlled Analgesia (PCA) is an effective and often preferred therapy for the treatment of chronic pain symptoms in the pediatric palliative care patient. There is little previous research of patient experience with Home PCA. The purpose of this study was to investigate use of home PCA devices in pediatric patients to inform palliative care providers considering an alternative management option for the treatment of end-of-life or chronic pain. A chart review was performed of patients prescribed home PCA. Surveys were sent to patients' guardians/caregivers. Questions referred to caregiver impression/satisfaction with information provided regarding use of the PCA machine, the medication used, the benefits and risks of PCA, monitoring of patient pain level and alertness, machine efficacy, and fears and concerns. Thirty-four patients met inclusion criteria, and 18 patient families completed surveys. Demographic data showed that the majority were Caucasian and had a cancer diagnosis. Patient age and duration of home PCA use varied greatly. Overall, participants were satisfied with information received and felt positively about home PCA, albeit expressing concerns. The majority described the machine as easy to use and were satisfied with their child's pain management and level of alertness. Responses indicated that home PCA is a manageable and effective alternative to traditional analgesic medications for management of chronic pain in the pediatric patient.

Comparison of dexmedetomidine and dexamethasone as adjuvant for ropivacaine in ultrasound-guided erector spinae plane block for video-assisted thoracoscopic lobectomy surgery: a randomized, double-blind, placebo-controlled trial.

Adding an adjuvant, such as dexmedetomidine or dexamethasone, to a nerve block improves its quality and reduces perioperative opioid consumption. We aimed to compare the effect of dexmedetomidine and dexamethasone as an adjuvant for the erector spinae plane block (ESPB) to control postoperative pain after video-assisted thoracoscopic lobectomy surgery (VATLS). Ninety patients, aged 20-65 years who were scheduled to undergo VATLS were enrolled in this trial. The visual analogue scale (VAS) score changes at various time points [waking up in post-anesthesia care unit (PACU) and 2, 4, 6, 8, 12, 24, 48, 72 h after surgery], duration of sensory block, first request to use the patient controlled analgesia (PCA) device, total PCA use, postoperative nausea and vomiting (PONV), rate of rescue analgesia use, and post-surgical hospital stay were recorded. VAS score was lower in the ropivacaine with dexmedetomidine (RM) group at wake up and at postoperative 2, 4, 12, and 24 h. The median duration of sensory blockade was significantly longer in the RM group (P=0.001). First request to use the PCA machine in the RM group was prolonged significantly compared with that in the ropivacaine alone (R) group and ropivacaine with dexamethasone (RS) group (P<0.001). Total PCA use, post-surgical hospital stay, and rate of rescue analgesia use in The RM group were reduced significantly compared with those in the R and RS groups. Using dexmedetomidine (1 µg/kg), instead of dexamethasone (10 mg), as an adjuvant of ESPB with ropivacaine, prolonged sensory block duration, provided effective acute pain control, and required lesser rescue analgesia and shorter hospital stays.

Intravenous lidocaine infusions for 48 hours in open colorectal surgery: a prospective, randomized, double-blinded, placebo-controlled trial.

BackgroundAlthough intravenous (i.v.) lidocaine is used as a perioperative analgesic in abdominal surgery, evidence of efficacy is limited. The infusion dose and duration remain unclear. This study aimed to investigate the effect of a longer low-dose 48-hour infusion regimen on these outcomes.MethodsFifty-eight adults undergoing elective open colorectal surgery were randomized into the lidocaine group (1.5 mg/kg bolus followed by 1 mg/kg/h infusion for 48 hours) and control group. After surgery, patients were given a fentanyl patient-controlled analgesia machine and time to first bowel movement (primary outcome) and flatus were recorded. Postoperative pain scores and fentanyl consumption were assessed for 72 hours.ResultsThere was no significant difference in time to first bowel movement (80.1 ± 42.2 vs. 82.5 ± 40.4 hours; P = 0.830), time to first flatus (64.7 ± 38.5 vs. 70.0 ± 31.2 hours; P = 0.568), length of hospital stay (9 [8–13] vs. 11 [9–14) days; P = 0.531], nor postoperative pain scores in the lidocaine vs. control groups. Cumulative opioid consumption was significantly lower in the lidocaine vs. the control group from 24 hours onwards. At 72 hours, cumulative opioid consumption (µg fentanyl) in the lidocaine group (1,570 [825–3,587]) was over 40% lower than in the placebo group (2,730 [1,778–5,327]; P = 0.039).ConclusionsA 48-hour low-dose i.v. lidocaine infusion does not significantly speed the return of bowel function in patients undergoing elective open colorectal surgery. It was associated with reduced postoperative opioid consumption, but not with earlier hospital discharge, or lower pain scores.

Drug overdose due to malfunction of a patient-controlled analgesia machine -A case report-

Patient-controlled analgesia (PCA) provides excellent pain control and high stability, thereby minimizing the incidence of adverse effects. However, one of our patients experienced respiratory depression and hypotension within 30 minutes of initiation of PCA therapy. We discovered that machine malfunction caused continuous activation of the PCA button, resulting in a drug overdose. The PCA machine was sent to the manufacturer, who found an electrical short in the PCA button. All PCA units of the same make and model were immediately removed from hospitals and replaced with redesigned units without defects in the PCA button. We have used the improved machines without any problems. The purpose of this report is to raise awareness of this type of malfunction in PCA units in order to help prevent adverse events in the future.

Postoperative Continuous Paravertebral Anesthetic Infusion for Pain Control in Posterior Cervical Spine Surgery

Patients who undergo posterior cervical spinal fusion procedures frequently experience significant postoperative pain. Use of a local anesthetic continuous infusion pump after surgery may improve these outcome variables. After posterior cervical spine fusion procedures, 25 consecutive patients received continuous infusion of 0.5% bupivacaine into the subfascial aspects of the wound via an elastomeric pump. Data were collected prospectively by third party assessment using standard nursing protocols. This included numeric pain scores and opiate use over the first 4 postoperative days (PODs), length of hospitalization, and complications. In a retrospective analysis, we compared each study patient to a control patient who did not receive the continuous infusion of bupivacaine. Demographic variables and surgical procedure were similar among matched cases. Patients receiving continuous local anesthetic infusion used significantly less narcotics (P < .05) during the first 4 PODs: 24.4% on day 1, 34.1% on day 2, 53.5% on day 3, and 58.1% on day 4. A lower average pain score was observed among study patients on each POD (P < .05): 31.5% less on day 1, 13.0% on day 2, 24.0% on day 3, and 35.7% on day 4. Patients with the infusion device were discharged home earlier (POD 4.9 versus 6.7; P = .024) and demonstrated improvement in time to ambulation, first bowel movement, and discontinuation of the patient-controlled analgesia machine. No complications were associated with the device. Patients with the local anesthetic continuous infusion device required less narcotics and reported lower pain scores than control patients on each of the first 4 PODs. These results suggest that continuous infusion of local anesthetic into the paravertebral tissue during the immediate postoperative period is a safe and effective technique that achieves lower pain scores and narcotic use and improves multiple postoperative outcome variables.

Spinal anaesthesia with a micro-catheter in high-risk patients undergoing colorectal cancer and other major abdominal surgery

Extended spinal anaesthesia using a spinal micro-catheter was used as a primary method of anaesthesia for elective colorectal cancer surgery in 68 high risk patients over a 14-year period in our institution. The technique was also useful in eight elective and 13 emergency abdominal surgeries. All patients suffered from severe chronic obstructive airway disease requiring multiple inhalers and drugs (ASA III). Thirty nine of these patients also suffered from angina, myocardial infarction, diabetes and other systemic diseases (ASA IV). Surgery included right hemicolectomy, left hemicolectomy, total colectomy, sigmoid colectomy, Hartman's resection, anterior resection of rectum, abdominoperineal resection, cholecystectomy (open and laparoscopic) and obstructed inguinal hernia requiring laparotomy. Spinal anaesthesia was performed under strict aseptic conditions with a 22 gauge spinal needle with a mixture consisting of 2.75ml of 0.5% heavy bupivacaine and 0.25ml of fentanyl (25microg). This was followed by placement of a spinal micro-catheter and the duration of anaesthesia was extended by intermittent injection of 0.5% isobaric bupivacaine. Brief hypotension occurred in 12.4% of patients during the establishment of anaesthetic block height to T6-7 and was duly treated with intravenous administration of fluid and ephedrine hydrochloride. Good anaesthesia resulted in all patients except for brief discomfort in some patients during hemicolectomy surgery possibly due to the dissection and traction on the peritoneum causing irritation to the diaphragm. The use of sedation was avoided. General anaesthesia was administered in one patient and this patient required postoperative ventilation and cardiovascular support in the Intensive Care Unit. The spinal micro-catheter was removed at the end of surgery. Postoperative pain relief was obtained by administering intravenous morphine through a patient controlled analgesia machine in the critical care ward area (High Dependency Unit). There was a low incidence of minor postoperative side effects such as nausea (14.6%), vomiting (7.9%), minor post dural puncture headache (5.6%) and pruritus (5.6%). We conclude that spinal anaesthesia with a micro-catheter may be used as a primary method of anaesthesia for colorectal cancer surgery and other major abdominal surgery in high-risk patients for whom general anaesthesia would be associated with higher morbidity and mortality.

Continuous Versus Single-Injection Lumbar Plexus Blocks: Comparison of the Effects on Morphine Use and Early Recovery After Total Knee Arthroplasty

Continuous lumbar plexus infusion of local anesthetic after total knee arthroplasty has been shown to improve analgesia and early recovery as compared with patient-controlled analgesia (PCA) morphine. Any benefit of an infusion over a single-injection lumbar plexus block has not been directly shown however. In a double-blind, randomized, controlled trial, 32 patients undergoing total knee arthroplasty were randomly allocated to 1 of 2 groups: 0.1% levobupivacaine infusion or saline infusion. Preoperatively, all patients received a lumbar plexus block with 25 mL 0.5% levobupivacaine using a posterior approach with a catheter left in situ, a sciatic nerve block with 15 mL 0.5% levobupivacaine, and a spinal anesthetic. At the end of surgery, 0.1% levobupivacaine or saline was infused into the catheter at 10 mL/h for 48 hours. All patients also received PCA morphine. The primary endpoint was morphine use from the PCA machine. Secondary endpoints included pain scores, day of first postoperative mobilization, and nausea. Patients receiving the levobupivacaine infusion used significantly less morphine than those receiving saline (19 mg [interquartile range (IQR) 8.5-29.5] vs 32 mg [IQR 23.5-53.0], P = .04) and also mobilized earlier postoperatively (day 1 or 2 [levobupivacaine] vs day 2 or 3 [saline], P = .001). Pain scores were similar. Postoperative infusion of local anesthetic around the lumbar plexus reduces morphine requirement and improves early recovery after total knee arthroplasty as compared with a single-injection block.

A Policy for Nurse-Administered Analgesic Dosing Through a Patient-Controlled Analgesic Device

Patient-controlled analgesia (PCA) has improved pain management in the hospital setting by decreasing the time it takes for patients to obtain intravenous analgesics and to allow for titration based on activity and level of pain. However, when patients are inappropriate for PCA because of cognitive impairment or physical inabilities, they are unable to obtain analgesics in such a timely manner and must wait longer periods of time for analgesics. In our institution, all of our continuous narcotic infusions are administered using a PCA machine for security purposes. But when the patients needed extra medication, the nurses would have to obtain these medications elsewhere. We developed a policy so that the PCA machine could be used to deliver the extra medication by the nurses when needed. This allows the nurse to perform a pain assessment, determine a need for analgesia, administer the prescribed dose, and document this information without leaving the bedside. When the nurse returns to evaluate the effectiveness of this dose, an additional dose of medication may be administered if indicated. We have found this to be invaluable for unplanned dressing changes, line placements, transfers, and other causes of active pain. It has also been useful for giving small doses of fentanyl to cognitively challenged elderly patients who would otherwise be ineligible for this medication. The outcome is diminished time needed to administer analgesia to the physically and cognitively impaired patients as well as decreasing nursing workload. PCA has replaced intermittent injections of narcotics for most patients. However, for those who are cognitively impaired or physically unable to press a PCA button, they must wait longer for their pain relief. In our institution, we developed a policy that allows nurses to administer narcotics using a PCA machine (Nurse Administered Analgesic Dosing), which decreases the time for medication delivery and improves patient comfort. The purpose of this clinical project is to educate nurses about how to safely use PCA devices to improve the delivery of PRN analgesics.

A prospective survey of patients after cessation of patient-controlled analgesia.

Cessation of IV patient-controlled analgesia (PCA) in the postoperative period is often an arbitrary clinical decision. We conducted a prospective survey of patients 24 h after cessation of IV PCA morphine to determine whether they wished to be restarted on PCA, and to evaluate factors affecting this decision. One hundred and fifteen patients were surveyed over a 3-mo period. Thirty-eight patients (33%) wished to restart PCA. The most common reason was the expectation that IV PCA would be more effective. Age, sex, type of surgery, duration of PCA use, side effects, pain scores, and reasons for cessation of PCA did not affect the decision. The reasons given by those who did not wish to restart PCA were minimal pain (51.9%), inconvenient PCA machine (15.6%), ineffective analgesia by IV PCA (11.7%), side effects during PCA (11.7%), and wishing to tolerate pain (7.8%). PCA morphine consumption in the 24-h period before cessation of PCA (mean [SD]) was larger in patients wishing to restart PCA than in those who did not (21.1 [14.8] mg vs 15.1 [15.1] mg; P < 0.05). In conclusion, the clinical decisions to cease IV PCA do not predict patient acceptance of and satisfaction with the decision and with subsequent pain treatment. Morphine consumption may predict a patient's acceptance of ceasing PCA. We surveyed patients 24 h after cessation of IV patient-controlled analgesia (PCA). This survey revealed that the usual clinical reasons to stop IV PCA might not be the most appropriate. Patients have different reasons why they wish to restart or not restart IV PCA. The cessation of PCA should be individualized.

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

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. Randomized, prospective study. Teaching hospital. 75 patients scheduled to receive PCA morphine following abdominal surgery. 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. 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). 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.

Analysis, Redesign, and Evaluation of a Patient-Controlled Analgesia Machine Interface

The hypothesis explored in this paper is that, by adopting human factors design principles, the use of medical equipment can be made safer and more efficient We have selected a commercially available patient-controlled analgesia (PCA) machine as a vehicle to test this hypothesis. A cognitive task analysis of PCA usage, combined with a set of human factors design principles, led to a redesigned PCA interface. An experimental evaluation was conducted, comparing this new interface with the existing interface. The results show that the new interface leads to significantly faster, less effortful, and more reliable performance. These findings have implications for improving the design of other medical equipment.

Effect of demand frequency on lockout period

An Abbott Provider 5500 Patient Controlled Analgesia machine was noticed to have developed a prolonged lockout period when frequent analgesic demands were being made. This study tested five other machines and demonstrated that the duration of the lockout period was influenced by the frequency of analgesic demands. This finding could have clinical implications and we recommend that the duration of the lockout period should be specifically examined during the testing of patient-controlled machines.

Effect of ilioinguinal and iliohypogastric nerve block and wound infiltration with 0.5% bupivacaine on postoperative pain after hernia repair

We have compared, in 40 adult males, the effect on pain in the first 24 h after herniorrhaphy of preincisional ilioinguinal and iliohypogastric nerve block and wound infiltration with 0.5% bupivacaine or saline. After operation, patients received morphine i.v. via a patient-controlled analgesia machine and visual analogue pain scores (VAS) at rest and on movement were recorded. The bupivacaine group consumed less morphine in the first 6 h after operation. There was no difference in morphine consumption between the two groups in the next 18 h. The time to first analgesia was delayed in the bupivacaine group and was not followed by a rebound increase in requirement for analgesia. There was no significant difference in VAS scores at rest but there was a significantly higher pain score with movement in the saline group. We have shown that the combination of nerve block and wound infiltration reduces consumption of morphine in the first 24 h after herniorrhaphy. We have failed to show any effect of 0.5% bupivacaine beyond the first 6 h after operation.

COMPARISON OF PATIENT-CONTROLLED ANALGESIA WITH AND WITHOUT A BACKGROUND INFUSION AFTER LOWER ABDOMINAL SURGERY IN CHILDREN

Forty children aged 6-12 yr undergoing appendicectomy were allocated randomly to receive postoperative i.v. morphine by a patient-controlled analgesia (PCA) system (bolus dose 20 micrograms kg-1 with a lockout interval of 5 min) or the same PCA with a background infusion of morphine 20 micrograms kg-1 h-1. Patients breathed air and oxygen saturation was monitored by continuous pulse oximetry. Scores for pain, sedation and nausea were recorded hourly. Patients with PCA + background infusion received significantly more morphine than those with PCA only. Both groups self-administered similar amounts of morphine using the PCA machine. There were no significant differences in the pain scores of the two groups. Patients with PCA+background infusion suffered more nausea (P < 0.01), more sedation (P < 0.05) and hypoxaemia (P < 0.001) than those with PCA only. They also had a better sleep pattern than those with PCA only.

Patient‐controlled analgesia with and without background infusion. Analgesia assessed using the demand: delivery ratio

Sixty adult patients following general surgical operation were treated with patient-controlled analgesia using morphine. Patients were allocated into three groups to receive: no background infusion, a 1 mg.h-1 or a 2 mg.h-1 background infusion. The other controls on the patient-controlled analgesia machine were set to allow a maximum dose of morphine of 6 mg.h-1 to each group. Analgesia was assessed after 4 and 24 h using a 100 mm horizontal visual analogue scale. The number of analgesic requests made by the patient and the number of those requests which resulted in successful deliveries was recorded. Patients who received a regimen including a background infusion had improved pain relief, particularly in the first 4 h of treatment (p < 0.05). Patients who received a background infusion of 2 mg.h-1 had an increased incidence of nausea (p < 0.05). A background infusion of 1 mg.h-1, with a 1 mg bolus dose and a 12 min lockout interval provided acceptable pain relief without excessive nausea. In all three groups the ratio of analgesic requests to successful deliveries correlated with the degree of pain reported by visual analogue score (p = 0.0001).

Patient-controlled Analgesia in the Total Joint Arthroplasty Patient

In a prospective study of 30 total hip or knee joint arthroplasty patients, the use of the patient-controlled analgesia (PCA) pump was evaluated for patient acceptance and relief of pain. In 30 patients, (average age, 72.5 years) excellent analgesia was obtained with the PCA machine without the side effects of conventional intramuscular dosing. PCA was enthusiastically received by nurses, physicians, and patients, and it has become the method of choice in the author's hospital.