Intrathecal Opioid Administration Research Articles

Efficacy and Safety of Intrathecal Morphine for Cesarean Delivery: A Narrative Review.

Pain management is a critical aspect of care during and following a cesarean delivery. Without proper control of pain, individuals can experience poor mobility, increased thromboembolic events, and difficulty caring for the neonate in the postpartum period. There have been multiple methods for pain management for cesarean delivery and intrathecal morphine (ITM) has emerged as a prominent option for post-operative analgesia due to its efficacy, safety, and potential benefits over other treatments. This review analyzes data on efficacy, side effects, and safety of ITM and the pain control alternatives. A comprehensive literature review was conducted to compare ITM with other analgesic techniques in post-cesarean patients. ITM was found to be as effective or better than other analgesic options, including bilateral quadratus lumborum block (QLB), opioid-free epidural analgesia (CSEA-EDA), and intravenous fentanyl. One study found that both ITM and oral analgesia were effective in pain control and that ITM caused fewer breakthrough pain events but had a longer duration and a greater rate of side effects than oral opioid analgesia. Commonly observed side effects of intrathecal opioids include nausea, vomiting, pruritus, and urinary retention, and it is thought that the adverse effects from intrathecal administration of opioids are short-lived. ITM may provide a decreased risk of DVT and coagulation by decreasing lower extremity weakness and numbness, thereby decreasing recovery time and increasing mobility. ITM is a safe and effective option for post-cesarean analgesia, with comparable pain relief to alternative forms of pain control, and side effects that are generally manageable. Further research is warranted to explore beneficial combinations with other methods of pain management and optimal dosing strategies.

Intrathecal Opioid Use in Kidney Transplantation: An Observational Cohort Study.

Kidney transplant is the most common transplant operation performed in the United States. Although various approaches to pain management have been described, the optimal analgesic strategy remains undefined. Specifically, the role of intrathecal opioids in this patient population has not been comprehensively evaluated. Using a retrospective cohort design, data from kidney transplant operations at a single tertiary care medical center between August 1, 2017, and July 31, 2022, were extracted. Inverse probability of treatment weighting (IPTW) was used to assess differences in clinical outcomes based on the presence or absence of intrathecal opioid administration before surgical incision. The primary outcome was total opioid exposure expressed in milligram morphine equivalents (MME) in the first 72 hours postoperatively, with secondary outcomes including total MME (intraoperative plus postoperative MME, postoperative pain scores, and the presence of postoperative nausea/vomiting [PONV], pruritus, or adverse events). A total of 1014 kidney transplants in 1012 unique patients were included, with 411 (41%) receiving intrathecal opioids preoperatively. Hydromorphone was the intrathecal opioid used in all cases with median dose of 100 µg (interquartile range [IQR], 100, 100; range 50-200). Subjects receiving intrathecal opioids had significantly lower postoperative opioid requirements at 72 hours (30 [0-68] vs 64 [22, 120] MME), with ratio of geometric means in the IPTW analysis (ratio of geometric means 0.34, 95% confidence interval [CI], 0.26-0.43; P < .001). Similar findings were observed for total opioids (45 [30-75] vs 75 [60-90] MME; ratio of geometric means 0.58, 95% CI, 0.54-0.63; P < .001). Maximum reported pain scores in the intrathecal group were lower at 24 hours (4 [2-7] vs 7 [5, 8]; OR, 0.28; 95% CI, 0.21-0.37 for experiencing a higher pain score with intrathecal opioids, P < .001) and 72 hours (6 [4-7] vs 7 [5-8]; OR, 0.41; 95% CI, 0.31-0.54; P < .001). Patients receiving intrathecal opioids were more likely to experience PONV (225 of 411 [55%] vs 232 of 603 [38%]; OR, 2.16; 95% CI, 1.63-2.86; P < .001). Intrathecal opioid administration was associated with improved pain outcomes in patients undergoing kidney transplantation, including lower opioid requirements and pain scores through 72 hours. However, this was accompanied by an increased risk of PONV.

The effect of intraoperative intrathecal opioid administration on the length of stay and postoperative pain control for patients undergoing lumbar interbody fusion.

In an effort to control postoperative pain more effectively in spinal fusion patients, intraoperative intrathecal morphine (ITM) administration is gaining popularity and acceptance with clinicians. This study seeks to determine the impact of intraoperative intrathecal opioid (ITO) administration following lumbar fusion surgery on postoperative pain and length of hospitalization as primary outcomes. Secondary outcomes will investigate postoperative opioid intake and side effects. The retrospective analysis of collected data was performed. The study compared patients undergoing one- or two-level transforaminal interbody fusions between 2019 and 2021 who intraoperatively received two different ITO doses (n = 89) vs. the reference group (n = 48) that did not receive ITO. The patients in the ITO group received either 0.2mg (n = 44) of duramorph or 0.2mg duramorph + 50 mcg fentanyl (n = 45). The effect of ITO was evaluated for the first four postoperative days (POD) on pain scores (visual analog scale), length of stay (LOS, hours) and opioid requirement (MED, morphine equivalent dose). In the ITO group, a significant reduction of postoperative pain scores (t(99) = 4.3,p < 0.001) and opioid intake (t(70) = 2.49,p = 0.015) was noted on POD1. Cohen's d effect sizes were 0.76 and 0.50, meaning that postoperative pain and MED intake were reduced by about ¾ to ½ standard deviations (SD) in the ITO group. Further, multivariate regression models revealed that ITO administration predicted lower postoperative pain scores for the two PODs (β = - 0.83, p < 0.001; β = - 0.63, p = 0.022) and MED intake for the first two PODs (β = - 20.8, p = 0.047; β = - 16.4, p = 0.030). Mean LOS was 15.4h less in the ITO group (mean ± SD, 63.4 ± 37.1 vs. 78.8 ± 39.6, p = 0.10). In conclusion, our study provides results in a large sample of patients undergoing transforaminal lumbar fusions. The results demonstrated that ITO administration is effective in reducing POD1 pain scores and POD1-2 opioid requirement while not increasing the risk of any opioid-related side effects.

Comparing Duration of Analgesia after Intrathecal Administration of Opioids in Primary Paturients for Lower Segment Cesarean Section.

Background:A pain free post operative period is a boon to mother for caring the neonate. We compared injection butorphanol and fentanyl as an adjuvant to bupivacaine in primary parturients for LSCS (Lower Segment Caesarean Section) with respect to duration of analgesia.Aims and Objectives:To study the effect of butorphanol vs fentanyl on duration of analgesia when added to bupivacaine for LSCS amongst primi parturients and to observe the block characteristics as secondary outcome.Materials and Methods::Study was carried out in 90 patients divided equally into three groups which included 12mg(2 mL) of 0.5% hyperbaric bupivacaine with 0.5 mL NS, 12mg (2 mL) of 0.5% hyperbaric bupivacaine 25 μg butorphanol made upto 2.5 mL with NS and 12mg(2 mL) of 0.5% hyperbaric bupivacaine with 25μg fentanyl made upto 2.5mL with normal saline. All patients were observed for duration of analgesia. Also Heart Rate (HR), Systolic and Diastolic Blood Pressure (SBP, DBP), two segment regression time of sensory block, motor block were assessed. The results were compiled and statistically analyzed using Chi-square test for nonparametric data and ANOVA for parametric data.Results:Two segment sensory regression is significantly prolonged in group with intrathecal administration of Bupivacaine with Butorphanol (190.33±15.86) than Bupivacaine with Fentanyl (170.67±20.83) and Bupivacaine with Normal saline (150.33±16.91). Duration of effective post operative analgesia was 349.67, 591.87 and 468.00 min in Group I, Group II and Group III respectively. There was no significant difference in onset of sensory and motor blockage in all three groups. HR, SBP and DBP were comparable among the groups.Conclusions:Intrathecal bupivacaine with 25 μg butorphanol mixture was clinically better as it provided longer duration of analgesia along with prolonged sensory block when compared to intrathecal bupivacaine with 25μg fentanyl mixture in primary parturients for LSCS.

Comparison between Intrathecal Nalbuphine and Bupivacaine versus Fentanyl and Bupivacaine For Postoperative Analgesia After Lower Abdominal Surgeries

Abstract The use of opioids in intrathecal or epidural anesthesia has become popular to optimize postoperative analgesia. However, opioid-induced side effects, such as respiratory depression, nausea, vomiting, urinary retention and pruritus, limit their use. Several investigations have shown that intrathecal or epidural administration of opioids produces a dose dependent modulation of spinal nociceptive processing in animals and humans and is not associated with sedation. Aim of Study The purpose of this study was to assess the spinally mediated analgesic effects postoperativally of intrathecal Nalbuphine plus bupivacaine after lower abdominal surgeries in comparison to intrathecal bupivacaine plus fentanyl Patients &amp; Methods : 60 patients came to Ain-shams Hospital for lower abdominal surgeries, They were randomly allocated into two equal groups (30 patients each) group F and group N. Group F : Bupivacaine-Fentanyl Patients received an intrathecal injection of 3 ml of 0.5% heavy (hyperbaric) bupivacaine plus 0.5 ml (25 µg) fentanyl. Group N: Bupivacaine-Nalbuphin Patients received an intrathecal injection of 3 ml of 0.5% heavy (hyperbaric) bupivacaine plus 0.5 ml (0.5 mg) Nalbuphine. All patients were assessed and monitored for: Hemodynamics: ECG for heart rate, and non-invasive arterial pressure, respiratory rate and arterial oxygen saturation, onset of sensory block, onset of motor block, duration of analgesia &amp; 1st rescue analgesia, duration of motor block, adverse effects as: hypotension, bradycardia, respiratory depression, pruritus, shivering, nausea and vomiting were recorded. Results &amp; Conclusion Addition of a small dose of nalbuphine or fentanyl to bupivacaine in spinal anesthesia moderately prolonged the time of postoperative analgesia the duration of postoperative analgesia is nearly the same in nalbuphine group &amp; the fentanyl group. There is more rapid onset of motor block in fentanyl group than in nalbuphine group but with no difference in sensory or motor block regression. No respiratory depression or degree of sedation occurs in both groups. Hemodynamic stability &amp; side effects incidence are the same in both groups

A study of haemodyanamine changes: a comparative pain score evaluation of lumbar epidural block using 0.5% bupivacaine and 0.5% bupivacaine with ketamine in orthopaedic surgery cases

Epidural block using local anaesthetic drugs are used in clinical practice since many years. It further got revolutionized with the better understanding of opioid receptors by Martin & Coworkers in1976. Intra spinal morphine was first used in 1979, which opened up a new exciting way of pain management. Intrathecal and epidural administration of opioids are widely used even now. Opioid administration intrathecally or epidurally causes dependable method of pain relief without affecting motor functions or other sensory modalities such as touch sensation. This study is an effort to find the haemodynamic changes of lumbar epidural block using 0.5% bupivacaine vs 0.5% bupivacaine with ketamine.

A study of pain score: a comparative pain score evaluation of lumbar epidural block using 0.5% bupivacaine and 0.5% bupivacaine with ketamine

Intrathecal and epidural administration of opioids are widely used even now. Opioid administration intrathecally or epidurally causes dependable method of pain relief without affecting motor functions or other sensory modalities such as touch sensation. This study is an effort to find the complications of lumbar epidural block using 0.5% bupivacaine vs 0.5% bupivacaine with ketamine.

A randomized controlled trial comparing tapentadol with oxycodone in non-breastfeeding women post elective cesarean section

Background: Tapentadol may allow greater pain relief with reduced “opioid load” compared to oxycodone. Its use has not been studied in the obstetric population. The objective of this study was to compare the efficacy and side effect profile of tapentadol with oxycodone in patients who received spinal anesthesia for elective cesarean section. The trial was registered with EU Clinical Trials Register with CT number 2016-001621-33.Methods: This was a multicenter, randomized controlled trial. Randomized patients (n = 68) received either 50 mg tapentadol or oxycodone 10 mg 12 hourly postoperatively. The primary endpoint was the sum of pain intensity difference over the first 48 hours of treatment (SPID48). Secondary outcomes included time to rescue medications, SPID36, total pain relief (TOTPAR) scores, patient satisfaction scores, sum of total pain relief and pain intensity difference (SPRID) scores, time to rescue medications and side effects experienced. An analysis of covariance model with baseline pain intensity score as a covariate was used for statistical analysis.Results: There was no significant difference in the primary endpoint of SPID48 with adjusted mean difference -11.45 (95% CI -35.35, 12.45) p = .34). Oxycodone showed significantly greater SPID36 scores compared to tapentadol with increased time to rescue medication. Side effects experienced were similar between groups.Conclusion: Tapentadol did not provide superior pain control or improved tolerability compared to oxycodone post cesarean section. Results should be interpreted however with consideration of administration of intrathecal opioids to all patients in this study and debate over the optimal dose of tapentadol for acute pain.Trial registration: EU Clinical Trials Register identifier: 2016-001621-33.

Determination of ED50 and time to effectiveness for intrathecal hydromorphone in laboring patients using Dixon\u2019s up-and-down sequential allocation method

BackgroundWith the increasing occurrence of drug shortages, understanding the pharmacokinetics of alternative intrathecal opioid administration has gained importance. In particular, additional data are needed to comprehensively evaluate the analgesic properties of intrathecal hydromorphone in the laboring patient. In a phase 2 clinical trial, we set out to determine the median effective dose (ED50) and time to effectiveness for this drug in this population.MethodsUsing Dixon’s up-and-down sequential allocation method, twenty women presenting for labor analgesia were prospectively enrolled. A combined spinal-epidural technique was used to deliver the determined dose of intrathecal hydromorphone. Visual analog pain scores were obtained assessing peak pain scores during serial uterine contractions. Effective pain relief was defined as achieving a pain score of less than or equal to 3 out of 10. The dose was deemed to be ineffective if the patient failed to achieve this level of relief after 30 min.ResultsThe ED50 of hydromorphone in our population was 10.9 μg (95% confidence interval 5.6–16.2 μg). Amongst patients for whom the dose was effective, the median time to pain relief was 24 min. One patient experienced both nausea and pruritus. No other complications were noted.ConclusionDue to the prolonged time to onset, hydromorphone cannot be recommended in favor of substantively better alternatives such as sufentanil and fentanyl.Trial registrationClinicaltrials.gov registration number: NCT01598506.

Comparative evaluation of Intrathecal Fentanyl with different doses of Bupivacaine on lower limb surgery

Introduction: Intrathecal administration of opioids and local anaesthetics provides good analgesia. Fentanyl potentiates the afferent surgical blockade and improves both intra and post operative analgesia. The synergism between intrathecal opioids and local anaestheticsachieves a reliable spinal anaesthesia with minimal hypotension. The optimal doses and dilutions of intrathecal combination of bupivacaine and fentanyl remain a subject of discussion. Therefore, we designed this study to compare the effects of different doses of hyperbaric bupivacaine 0.5% (10 mg, 12.5 mg, 15 mg) with fentanyl 25 microgram in subarachnoid block on quality of anaesthesia and recovery. Objectives: To observe sensory and motor blockcharacteristics and effects of different doses of bupivacaine on haemodynamic parameters. Method: A prospective randomized study was carried out on three groups of 20 each. Group A patients were given 0.5% hyperbaric bupivacaine 10 mg, fentanyl 25 µg and 0.9% normal saline 1.5 ml. Group B patients were given with 0.5% hyperbaric bupivacaine 12.5 mg, fentanyl 25 µg and 0.9% normal saline 1ml. Group C patients were given 0.5% hyperbaric bupivacaine 15 mg, fentanyl 25 µg and 0.9% normal saline 0.5 ml. Results: Duration of sensory block was prolonged in group C (139.50±16.05 minutes) than group A (129.00±18.32 minutes). On statistical comparison, group B and C (126.25±15.29 minutes and 132.75±10.70 minutes respectively) had significant prolonged duration of motor block than group A (114.00±18.11 minutes). Conclusion: Fentanyl 25µg with 0.5% hyperbaric bupivacaine 12.5 mg is superior in terms of characteristics of sensory and motor block and haemodynamic stability.

Prophylactic Pentazocine Reduces the Incidence of Pruritus After Cesarean Delivery Under Spinal Anesthesia With Opioids: A Prospective Randomized Clinical Trial.

The incidence of pruritus after cesarean delivery under spinal anesthesia with opioids is high, ranging from 50% to 100%. Pruritus is difficult to prevent; however, pentazocine has been shown to be an effective treatment. Despite this, the prophylactic effect of pentazocine on pruritus has not been defined. This randomized double-blind trial aimed to evaluate the effect of intraoperative IV pentazocine on the incidence of opioid-induced pruritus within the first 24 hours after administration of neuraxial opioids. We obtained institutional review board approval and written informed consent from the 122 patients (American Society of Anesthesiologists [ASA] physical status II; aged 20-40 years) scheduled for elective cesarean delivery who were included in this study. Spinal anesthesia was performed with 10 mg of 0.5% hyperbaric bupivacaine, 10 μg of fentanyl, and 100 μg of morphine. After delivery of the baby and placenta, the parturient women were randomized to intravenously receive 15 mg (1 mL) of pentazocine or 1 mL of saline. All women received postoperative analgesia with the epidural infusion of 0.15% levobupivacaine. The presence of pruritus within the first 24 hours after intrathecal administration of opioids was recorded, and severity of itch, numerical rating scale (NRS) for pain, and adverse effects were also recorded at the time of the arrival on the ward, as well as 3, 6, 12, and 24 hours after the intrathecal administration of opioids. A total of 119 women completed the study. IV pentazocine reduced the overall incidence of pruritus within the first 24 hours compared to IV saline, with an estimated relative risk of 69% (95% confidence interval [CI], 52%, 90%; P = .007). IV pentazocine also reduced the severity of pruritus. The incidence of nausea and vomiting was not significantly different. There were no significant differences in postoperative NRS scores. A single 15-mg dose of IV pentazocine after delivery can reduce both the incidence and severity of pruritus in women who have received subarachnoid opioids during cesarean delivery.

Geburtshilfe: kombinierte Spinal-Epidural-Analgesie (CSE)

Due to intrathecal application, CSE combines rapid response with adequate analgesia with the possibility of providing unlimited neuraxial obstetrical pain relief via the indwelling epidural catheter. The superiority of CSE over EDA lies above all in its rapid action, excellent analgesia, lack of motor blockade after a single intrathecal opioid administration, lower rate of unilateral blockages and less need for subsequent epidural injections. The most common side effect is pruritus, which is harmless and usually does not require any therapeutic intervention. Even if no effect on rate of C-sections and APGAR values have been observed, the increased rate of fetal bradycardia after CSE must be kept in mind. A reduction of these fetal bradycardias and after intrathecal administration, prolongation of analgesia by means of appropriate drug combinations or additives should be the subject of future research.

Postoperative pain after total abdominal hysterectomy and bilateral salpingo-oophorectomy depending on the type of anaesthesia administration

ABSTRACTTotal abdominal hysterectomy and bilateral salpingo-oophorectomy is a surgical procedure frequently associated with severe or moderate postoperative pain. We conducted a retrospective study on 90 patients who underwent this procedure. One part of the patients (58; 64.4%) was administered bupivacaine 5% without intrathecal opioid administration. The other part (32; 35.6%) underwent general anaesthesia with endotracheal intubation. We evaluated the postoperative analgesic requirements based on the type of anaesthesia used and other factors like age, environment and body mass index. The findings indicated that the patients who received general anaesthesia with endotracheal intubation developed severe postoperative pain more frequently than those who underwent spinal anaesthesia (P = 0.018). A higher percentage of patients from rural areas scored lower in postoperative pain intensity on the numerical rating scale (P = 0.033). There was no statistically significant correlation regarding postoperative pain and age or body mass index.

Mechanisms of ventilatory control: who is really in charge?

Mechanisms of ventilatory control: who is really in charge?

Longevity and cost of implantable intrathecal drug delivery systems for chronic pain management: a retrospective analysis of 365 patients.

Intrathecal drug delivery systems represent an important component of interventional strategies for refractory chronic pain syndromes. Continuous intrathecal administration of opioids results in higher subarachnoid drug concentrations, improved pain scores, and less frequent side effects when compared with systemic opioid administration. Substantial costs arise at the time of surgical implantation and at revision for battery depletion or treatment of a complication. Despite current widespread use, the real-world longevity and cost of implanted intrathecal pumps (ITP) has not been fully quantified. Patients with an ITP implanted at Cleveland Clinic Pain Management Center between January 1998 and December 2012 were included. ITP longevity was calculated as the time between implant and explant for depletion of the system's battery. Using the 2013 fee schedule of the Centers for Medicare & Medicaid Services, the daily cost of having a functioning ITP was calculated. The costs of office visits for pump refills and the cost of intrathecal medications were not included, nor were the possible savings due to decreased utilization of alternate medical services. Three hundred sixty-five patients had 559 pumps implanted. Postlaminectomy syndrome was the most common indication (40%). The median system longevity for all pumps was 5.4 years (97.5% confidence interval: [5.0, 5.8]), including pumps extracted prematurely, as well as those that reached the elective replacement interval. The median ITP longevity was 5.9 years (95% confidence interval: [5.6, 6.1]) for pumps explanted for end of battery life. The median system cost per day was $10.46. The median cost per day of pumps explanted for end of battery life was $9.26, versus $44.59 for pumps explanted prematurely due to complications. Overall, the cohort experienced an increased incidence of pump-related complications and a device longevity that was within the range of the manufacturer's anticipated lifespan. Increasing the lifespan of the ITP and improving patient selection have the potential to significantly improve the cost-effectiveness of intrathecal therapy.

Hipoacusia en un paciente tras administración de morfina intratecal

The administration of intrathecal opioids is a common technique when treating patients with chronic pain. The chosen drug is morphine due to its pharmacokinetic characteristics that determine a good analgesic quality, still required monitoring of patients for the first 24 hours because of their fundamental risk of respiratory depression. We present a case of hearing loss associated with opioid intoxication after administration of morphine by intrathecal infusion pump in a patient with chronic pain with post-laminectomy syndrome. The patient was treated with respiratory support and continuous intravenous infusion of naloxone. The hearing loss reverted within one hour after gradual increase of the treatment. The different articles that we analyzed include nausea, vomiting, pruritus, urinary retention and respiratory depression as side effects of intrathecal morphine. There is no reference to the onset of hearing loss associated with intrathecal opioid intoxicaton in the literature we have reviewed so far.

Delivery Systems of Opioid Analgesics for Pain Relief: A Review

Chronic pain is usually treated with pharmacological measures using opioids alone or in combination with adjuvant analgesics that play an important role in the treatment of pain not fully responsive to opioids administered alone, especially in neuropathic, bone and visceral colicky pain. The important part of the chronic pain treatment is the appropriate use of non-pharmacological measures along with psychosocial and spiritual support. Opioids may be administered by different routes; the most common and most convenient for majority of treated patients are oral and transdermal. However, in certain circumstances such as inability to swallow, lack of analgesic efficacy and intractable opioid-induced adverse effects parenteral routes (subcutaneous, intravenous) might be more useful. When these routes fail, in some patients intrathecal administration of opioids is required. Recently, more patients have been treated with short-acting opioids for breakthrough pain with sublingual, buccal and intranasal routes of opioid administration that may provide efficacy superior to oral and comparable to intravenous routes. Alternative routes comprise rectal, inhaled and topical administration of opioids. This article discusses various routes of opioid administration.

Influence of locomotor muscle afferent inhibition on the ventilatory response to exercise in heart failure

What is the central question of this study? Patients with heart failure often develop ventilatory abnormalities at rest and during exercise, but the mechanisms underlying these abnormalities remain unclear. This study investigated the influence of inhibiting afferent neural feedback from locomotor muscles on the ventilatory response during exercise in heart failure patients. What is the main finding and its importance? Our results suggest that inhibiting afferent feedback from locomotor muscle via intrathecal opioid administration significantly reduces the ventilatory response to exercise in heart failure patients. Patients with heart failure (HF) develop ventilatory abnormalities at rest and during exercise, but the mechanism(s) underlying these abnormalities remain unclear. We examined whether the inhibition of afferent neural feedback from locomotor muscles during exercise reduces exercise ventilation in HF patients. In a randomized, placebo-controlled design, nine HF patients (age, 60 ± 2 years; ejection fraction, 27 ± 2%; New York Heart Association class 2 ± 1) and nine control subjects (age, 63 ± 2 years) underwent constant-work submaximal cycling (65% peak power) with intrathecal fentanyl (impairing the cephalad projection of opioid receptor-sensitive afferents) or sham injection. The hypercapnic ventilatory response was measured to determine whether cephalad migration of fentanyl occurred. There were no differences in hypercapnic ventilatory response within or between groups in either condition. Despite a lack of change in ventilation, tidal volume or respiratory rate, HF patients had a mild increase in arterial carbon dioxide (P(aCO(2)) and a decrease in oxygen (P(aO(2)); P < 0.05 for both) at rest. The control subjects demonstrated no change in P(aCO(2)), P(aO(2)), ventilation, tidal volume or respiratory rate at rest. In response to fentanyl during exercise, HF patients had a reduction in ventilation (63 ± 6 versus 44 ± 3 l min(-1), P < 0.05) due to a lower respiratory rate (30 ± 1 versus 26 ± 2 breaths min(-1), P < 0.05). The reduced ventilation resulted in lower P aO 2 (97.6 ± 2.5 versus 79.5 ± 3.0 mmHg, P < 0.05) and increased P(aCO(2)) (37.3 ± 0.9 versus 43.5 ± 1.1 mmHg, P < 0.05), with significant improvement in ventilatory efficiency (reduction in the ventilatory equivalent for carbon dioxide; P < 0.05 for all). The control subjects had no change in ventilation or measures of arterial blood gases. These data suggest that inhibition of afferent feedback from locomotor muscle significantly reduces the ventilatory response to exercise in HF patients.

Combined Paravertebral and Intrathecal vs Thoracic Epidural Analgesia for Post-Thoracotomy Pain Relief

Background Although thoracic epidural analgesia (TEA) is considered the gold standard for post-thoracotomy pain relief, thoracic paravertebral block (PVB) and intrathecal opioid (ITO) administration have also been shown to be efficacious. We hypothesized that the combination of PVB and ITO provides analgesia comparable with that of TEA. Methods After local ethics committee approval, 84 consecutive patients undergoing open thoracic procedures were randomized to the TEA (ropivacaine 0.2%+sufentanil) or the PVB (ropivacaine 0.5%)+ITO (sufentanil+morphine) group. The primary endpoints were pain intensities at rest and during coughing/movement at 1, 2, 4, 8, 12, 24, 48, and 72 h after operation assessed by visual analogue scale (VAS) score. Data were analysed by multivariate analysis (anova; P Results Patient and surgical characteristics were comparable between the groups. The mean and maximal VAS scores were lower in the TEA (n=43) than in the PVB+ITO group (n=37) at several time points at rest (P Conclusions Although VAS scores were statistically lower in the TEA compared with the PVB+ITO group at some observation points, the differences were small and of questionable clinical relevance. Thus, combined PVB and ITO can be considered a satisfactory alternative to TEA for post-thoracotomy pain relief. ClinicalTrials.gov number. NCT00493909.

Effects of Intrathecal Opioid Administration on Pituitary Function

To report a case of panhypopituitarism in a patient receiving long-term intrathecal opioids. This is a case study and review of current medical literature. There is a 7-year follow-up time. One adult male clinic patient with pituitary dysfunction. Intrathecal opioids may lead to pituitary dysfunction. Intrathecal opioid pain management may produce some generalized effects, as well as pituitary hypofunction, as evidenced by this case. This patient experienced simultaneous suppression of multiple anterior pituitary hormones, which persisted with chronic oral opioid therapy following cessation of an intrathecal opioid pump. All hypothalamic pituitary axes, seem potentially vulnerable to therapy with intrathecal opioids. When patients are receiving these medications, symptoms need to be critically evaluated with appropriate laboratory assessments for suspected pituitary dysfunction. Further studies are required in order to create formal recommendations for routine patient surveillance during intrathecal opioid therapy.