Single-dose intravenous diclofenac for acute postoperative pain in adults

Advances in Formulations of Microneedle System for Rheumatoid Arthritis Treatment

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic joint inflammation, eventually leading to severe disability and premature death. At present, the treatment of RA is mainly to reduce inflammation, swelling, and pain. Commonly used drugs are non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, and disease-modifying anti-rheumatic drugs (DMARDs). These drugs lack specificity and require long-term, high-dose administration, which can cause serious adverse effects. In addition, the oral, intravenous, and intra-articular injections will reduce patient compliance, resulting in high cost and low bioavailability. Due to these limitations, microneedles (MNs) have emerged as a new strategy to efficiently localize the drugs in inflamed joints for the treatment of RA. MNs can overcome the cuticle barrier of the skin without stimulating nerves and blood vessels. Which can increase patient compliance, improve bioavailability, and avoid systemic circulation. This review summarizes and evaluates the application of MNs in RA, especially dissolving MNs (DMNs). We encourage the use of MNs to treat RA, by describing the general properties of MNs, materials, preparation technology, drug release mechanism, and advantages. Furthermore, we discussed the biological safety, development prospects, and future challenges of MNs, hoping to provide a new strategy for the treatment of RA.

Diclofenac for acute postoperative pain in children

BACKGROUND

Many children undergo various surgeries, which often lead to acute postoperative pain. This pain influences recovery and quality of life. Non-steroidal anti-inflammatory drugs (NSAIDs), specifically cyclo-oxygenase (COX) inhibitors such as diclofenac, can be used to treat pain and reduce inflammation. There is uncertainty regarding diclofenac's benefits and harms compared to placebo or other drugs for postoperative pain.

OBJECTIVES

To assess the efficacy and safety of diclofenac (any dose) for acute postoperative pain management in children compared with placebo, other active comparators, or diclofenac administered by different routes (e.g. oral, rectal, etc.) or strategies (e.g. 'as needed' versus 'as scheduled').

SEARCH METHODS

We used standard, extensive Cochrane search methods. We searched CENTRAL, MEDLINE, and trial registries on 11 April 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in children under 18 years of age undergoing surgery that compared diclofenac (delivered in any dose and route) to placebo or any active pharmacological intervention. We included RCTs comparing different administration routes of diclofenac and different strategies.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were: pain relief (PR) reported by the child, defined as the proportion of children reporting 50% or better postoperative pain relief; pain intensity (PI) reported by the child; adverse events (AEs); and serious adverse events (SAEs). We presented results using risk ratios (RR), mean differences (MD), and standardised mean differences (SMD), with the associated confidence intervals (CI).

MAIN RESULTS

We included 32 RCTs with 2250 children. All surgeries were done using general anaesthesia. Most studies (27) included children above age three. Only two studies had an overall low risk of bias; 30 had an unclear or high risk of bias in one or several domains. Diclofenac versus placebo (three studies) None of the included studies reported on PR or PI. We are very uncertain about the benefits and harms of diclofenac versus placebo on nausea/vomiting (RR 0.83, 95% CI 0.38 to 1.80; 2 studies, 100 children) and any reported bleeding (RR 3.00, 95% CI 0.34 to 26.45; 2 studies, 100 children), both very low-certainty evidence. None of the included studies reported SAEs. Diclofenac versus opioids (seven studies) We are very uncertain if diclofenac reduces PI at 2 to 24 hours postoperatively compared to opioids (median pain intensity 0.3 (interquartile range (IQR) 0.0 to 2.5) for diclofenac versus median 0.7 (IQR 0.1 to 2.4) in the opioid group; 1 study, 50 children; very low-certainty evidence). None of the included studies reported on PR or PI for other time points. Diclofenac probably results in less nausea/vomiting compared to opioids (41.0% in opioids, 31.0% in diclofenac; RR 0.75, 95% CI 0.58 to 0.96; 7 studies, 463 participants), and probably increases any reported bleeding (5.4% in opioids, 16.5% in diclofenac; RR 3.06, 95% CI 1.31 to 7.13; 2 studies, 222 participants), both moderate-certainty evidence. None of the included studies reported SAEs. Diclofenac versus paracetamol (10 studies) None of the included studies assessed child-reported PR. Compared to paracetamol, we are very uncertain if diclofenac: reduces PI at 0 to 2 hours postoperatively (SMD -0.45, 95% CI -0.74 to -0.15; 2 studies, 180 children); reduces PI at 2 to 24 hours postoperatively (SMD -0.64, 95% CI -0.89 to -0.39; 3 studies, 300 children); reduces nausea/vomiting (RR 0.47, 95% CI 0.25 to 0.87; 5 studies, 348 children); reduces bleeding events (RR 0.57, 95% CI 0.12 to 2.62; 5 studies, 332 participants); or reduces SAEs (RR 0.50, 95% CI 0.05 to 5.22; 1 study, 60 children). The evidence certainty was very low for all outcomes. Diclofenac versus bupivacaine (five studies) None of the included studies reported on PR or PI. Compared to bupivacaine, we are very uncertain about the effect of diclofenac on nausea/vomiting (RR 1.28, 95% CI 0.58 to 2.78; 3 studies, 128 children) and SAEs (RR 4.52, 95% CI 0.23 to 88.38; 1 study, 38 children), both very low-certainty evidence. Diclofenac versus active pharmacological comparator (10 studies) We are very uncertain about the benefits and harms of diclofenac versus any other active pharmacological comparator (dexamethasone, pranoprofen, fluorometholone, oxybuprocaine, flurbiprofen, lignocaine), and for different routes and delivery of diclofenac, due to few and small studies, no reporting of key outcomes, and very low-certainty evidence for the reported outcomes. We are unable to draw any meaningful conclusions from the numerical results.

AUTHORS' CONCLUSIONS

We remain uncertain about the efficacy of diclofenac compared to placebo, active comparators, or by different routes of administration, for postoperative pain management in children. This is largely due to authors not reporting on clinically important outcomes; unclear reporting of the trials; or poor trial conduct reducing our confidence in the results. We remain uncertain about diclofenac's safety compared to placebo or active comparators, except for the comparison of diclofenac with opioids: diclofenac probably results in less nausea and vomiting compared with opioids, but more bleeding events. For healthcare providers managing postoperative pain, diclofenac is a COX inhibitor option, along with other pharmacological and non-pharmacological approaches. Healthcare providers should weigh the benefits and risks based on what is known of their respective pharmacological effects, rather than known efficacy. For surgical interventions in which bleeding or nausea and vomiting are a concern postoperatively, the risks of adverse events using opioids or diclofenac for managing pain should be considered.

Comprehensive Strategies in Endodontic Pain Management: An Integrative Narrative Review

This narrative review comprehensively examines the current and emerging strategies for pain management in endodontics, encompassing a wide range of pharmacological and non-pharmacological approaches. Through an extensive exploration of 20 distinct parts, the review discusses traditional analgesics, antibiotics, the use of corticosteroids, and the role of novel treatments such as platelet-rich fibrin (PRF) and cryotherapy. The review also delves into the intricacies of clinical methods, such as trephination and occlusal reduction, and discusses the potential of advanced techniques such as GABAergic signaling, acupuncture, in silico modulation, and low-level laser therapy (LLLT) for the effective management of endodontic pain. The analysis reveals a trend toward integrative methods that combine established practices with cutting-edge research, highlighting the importance of a tailored approach in endodontic pain management. The findings underscore the significance of understanding the complex nature of dental pain and the need for multifaceted treatment strategies. The review emphasizes that while traditional pharmacological methods remain foundational, emerging therapies offer promising adjuncts or alternatives, especially in cases where conventional treatments may be inadequate or unsuitable. This review aims to serve as a comprehensive resource for endodontic practitioners and researchers, offering insights into the multifarious aspects of pain management in endodontics. It underscores the ongoing evolution in the field and suggests directions for future research, particularly in refining and validating new pain management techniques.

Diclofenac for acute postoperative pain in children

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the efficacy and safety of diclofenac (any dose) for acute postoperative pain management in children compared with placebo, other active comparators, or diclofenac administered by either different routes (e.g. oral, rectal, etc.) or strategies (e.g. as needed versus as scheduled).

Is Homeopathic Arnica Effective for Postoperative Recovery? A Meta-analysis of Placebo-Controlled and Active Comparator Trials

Background: Homeopathic Arnica montana is used in surgery as prevention or treatment for the reduction of pain and other sequelae of surgery. Our aim was to perform a metaanalysis of clinical trials to assess efficacy of Arnica montana to reduce the inflammatory response after surgery.

Method: We conducted a systematic review and metaanalysis, following a predefined protocol, of all studies on the use of homeopathic Arnica montana in surgery. We included all randomized and nonrandomized studies comparing homeopathic Arnica to a placebo or to another active comparator and calculated two quantitative metaanalyses and appropriate sensitivity analyses. We used “Hegde's g,” an effect size estimator which is equivalent to a standardized mean difference corrected for small sample bias. The PROSPERO registration number is CRD42020131300.

Results: Twenty-three publications reported on 29 different comparisons. One study had to be excluded because no data could be extracted, leaving 28 comparisons. Eighteen comparisons used placebo, nine comparisons an active control, and in one case Arnica was compared to no treatment. The metaanalysis of the placebo-controlled trials yielded an overall effect size of Hedge's g = 0.18 (95% confidence interval −0.007/0.373; p = 0.059). Active comparator trials yielded a highly heterogeneous significant effect size of g = 0.26. This is mainly due to the large effect size of nonrandomized studies, which converges against zero in the randomized trials.

Conclusion: Homeopathic Arnica has a small effect size over and against placebo in preventing excessive hematoma and other sequelae of surgeries. The effect is comparable to that of anti-inflammatory substances.

Single-dose intravenous ibuprofen for acute postoperative pain in adults

BACKGROUND

Postoperative administration of non-steroidal anti-inflammatory drugs (NSAIDs) reduces patient opioid requirements and, in turn, may reduce the incidence and severity of opioid-induced adverse events (AEs).

OBJECTIVES

To assess the analgesic efficacy and adverse effects of single-dose intravenous (IV) ibuprofen, compared with placebo or an active comparator, for moderate-to-severe postoperative pain in adults.

SEARCH METHODS

We searched the following databases without language restrictions: CENTRAL, MEDLINE, Embase and LILACS on 10 June 2021. We checked clinical trials registers and reference lists of retrieved articles for additional studies.

SELECTION CRITERIA

We included randomized trials that compared a single postoperative dose of intravenous (IV) ibuprofen with placebo or another active treatment, for treating acute postoperative pain in adults following any surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently considered trials for review inclusion, assessed risk of bias, and extracted data. Our primary outcome was the number of participants in each arm achieving at least 50% pain relief over a 4- and 6-hour period. Our secondary outcomes were time to, and number of participants using rescue medication; withdrawals due to lack of efficacy, adverse events (AEs), and for any other cause; and number of participants reporting or experiencing any AE, serious AEs (SAEs), and specific NSAID-related or opioid-related AEs. We were not able to carry out any planned meta-analysis. We assessed the certainty of the evidence using GRADE.

MAIN RESULTS

Only one study met our inclusion criteria, involving 201 total participants, mostly female (mean age 42 years), undergoing primary, unilateral, distal, first metatarsal bunionectomy (with osteotomy and internal fixation). Ibuprofen 300 mg, placebo or acetaminophen 1000 mg was administered intravenously to participants reporting moderate pain intensity the day after surgery. Since we identified only one study for inclusion, we did not perform any quantitative analyses. The study was at low risk of bias for most domains. We downgraded the certainty of the evidence due to serious study limitations, indirectness and imprecision. Ibuprofen versus placebo Findings of the single study found that at both the 4-hour and 6-hour assessment period, the proportion of participants with at least 50% pain relief was 32% (24/76) for those assigned to ibuprofen and 22% (11/50) for those assigned to placebo. These findings produced a risk ratio (RR) of 1.44 (95% confidence interval (CI) 0.77 to 2.66 versus placebo for at least 50% of maximum pain relief over the 4-hour and 6-hour period (very low-certainty evidence). Median time to rescue medication was 101 minutes for ibuprofen and 71 minutes for placebo (1 study, 126 participants; very low-certainty evidence). The number of participants using rescue medication was not reported within the included study. During the study (1 study, 126 participants), 58/76 (76%) of participants assigned to ibuprofen and 39/50 (78%) assigned to placebo reported or experienced any adverse event (AE), (RR 0.98, 95% CI 0.81 to 1.19; low-certainty evidence). No serious AEs (SAEs) were experienced (1 study, 126 participants; very low-certainty evidence). Ibuprofen versus active comparators Ibuprofen (300 mg) was similar to the active comparator, IV acetaminophen (1000 mg) at 4 hours and 6 hours (1 study, 126 participants). For those assigned to active control (acetaminophen), the proportion of participants with at least 50% pain relief was 35% (26/75) at 4 hours and 31% (23/75) at 6 hours. At 4 hours, these findings produced a RR of 0.91 (95% CI 0.58 to 1.43; very low-certainty evidence) versus active comparator (acetaminophen). At 6 hours, these findings produced a RR of 1.03 (95% CI 0.64 to 1.66; very low-certainty evidence) versus active comparator (acetaminophen). Median time to rescue medication was 101 minutes for ibuprofen and 125 minutes for the active comparator, acetaminophen (1 study, 151 participants; very low-certainty evidence). The number of participants using rescue medication was not reported within the included study. During the study, 8/76 (76%) of participants assigned to ibuprofen and 45/75 (60%) assigned to active control (acetaminophen) reported or experienced any AE, (RR 1.27, 95% CI 1.02 to 1.59; very low-certainty evidence). No SAEs were experienced (1 study, 151 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

There is insufficient evidence to support or refute the suggestion that IV ibuprofen is effective and safe for acute postoperative pain in adults.

A performance comparison of the most commonly used minimally invasive monitors of cardiac output

BACKGROUND

Shock is common in critically ill and injured patients. Survival during shock is highly dependent on rapid restoration of tissue oxygenation with therapeutic goals based on cardiac output (CO) optimization. Despite the clinical availability of numerous minimally invasive monitors of CO, limited supporting performance data are available.

METHODS

Following approval of the University of Saskatchewan Animal Research Ethics Board, we assessed the performance and trending ability of PiCCOplus™, FloTrac™, and CardioQ-ODM™ across a range of CO states in pigs. In addition, we assessed the ability of invasive mean arterial blood pressure (iMAP) to follow changes in CO using a periaortic transit-time flow probe as the reference method. Statistical analysis was performed with function-fail, bias and precision, percent error, and linear regression at all flow, low-flow (> 1 standard deviation [SD] below the mean), and high-flow (> 1 SD above the mean) CO conditions.

RESULTS

We made a total of 116,957 paired CO measurements. The non-invasive CO monitors often failed to provide a CO value (CardioQ-ODM: 40.6% failed measurements; 99% confidence interval [CI], 38.5 to 42.6; FloTrac: 9.6% failed measurements; 99% CI, 8.7 to 10.5; PiCCOplus: 4.7% failed measurements; 99% CI, 4.5 to 4.9; all comparisons, P < 0.001). The invasive mean arterial pressure provided zero failures, failing less often than any of the tested CO monitors (all comparisons, P < 0.001). The PiCCOplus was most interchangeable with the flow probe at all flow states: PiCCOplus (20% error; 99% CI, 19 to 22), CardioQ-ODM (25% error; 99% CI, 23 to 27), FloTrac (34% error; 99% CI, 32 to 38) (all comparisons, P < 0.001). At low-flow states, CardioQ-ODM (43% error; 99% CI, 32 to 63) and Flotrac (45% error; 99% CI, 33 to 70) had similar interchangeability (P = 0.07), both superior to PiCCOplus (48% error; 99% CI, 42 to 60) (P < 0.001). Regarding CO trending, the CardioQ-ODM (correlation coefficient, 0.82; 99% CI, 0.81 to 0.83) was statistically superior to other monitors including iMAP, but at low flows iMAP (correlation coefficient, 0.58; 99% CI, 0.58 to 0.60) was superior to all minimally invasive CO monitors (all comparisons P < 0.001).

CONCLUSIONS

None of the minimally invasive monitors of CO performed well at all tested flows. Invasive mean arterial blood pressure most closely tracked CO change at critical flow states.

Single-dose intravenous ketorolac for acute postoperative pain in adults

BACKGROUND

Postoperative pain is common and may be severe. Postoperative administration of non-steroidal anti-inflammatory drugs (NSAIDs) reduces patient opioid requirements and, in turn, may reduce the incidence and severity of opioid-induced adverse events (AEs).

OBJECTIVES

To assess the analgesic efficacy and adverse effects of single-dose intravenous ketorolac, compared with placebo or an active comparator, for moderate to severe postoperative pain in adults.

SEARCH METHODS

We searched the following databases without language restrictions: CENTRAL, MEDLINE, Embase and LILACS on 20 April 2020. We checked clinical trials registers and reference lists of retrieved articles for additional studies.

SELECTION CRITERIA

Randomized double-blind trials that compared a single postoperative dose of intravenous ketorolac with placebo or another active treatment, for treating acute postoperative pain in adults following any surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.  Our primary outcome was the number of participants in each arm achieving at least 50% pain relief over a four- and six-hour period. Our secondary outcomes were time to and number of participants using rescue medication; withdrawals due to lack of efficacy, adverse events (AEs), and for any other cause; and number of participants experiencing any AE, serious AEs (SAEs), and NSAID-related or opioid-related AEs. For subgroup analysis, we planned to analyze different doses of parenteral ketorolac separately and to analyze results based on the type of surgery performed. We assessed the certainty of evidence using GRADE.

MAIN RESULTS

We included 12 studies, involving 1905 participants undergoing various surgeries (pelvic/abdominal, dental, and orthopedic), with 17 to 83 participants receiving intravenous ketorolac in each study. Mean study population ages ranged from 22.5 years to 67.4 years. Most studies administered a dose of ketorolac of 30 mg; one study assessed 15 mg, and another administered 60 mg. Most studies had an unclear risk of bias for some domains, particularly allocation concealment and blinding, and a high risk of bias due to small sample size. The overall certainty of evidence for each outcome ranged from very low to moderate. Reasons for downgrading certainty included serious study limitations, inconsistency and imprecision. Ketorolac versus placebo Very low-certainty evidence from eight studies (658 participants) suggests that ketorolac results in a large increase in the number of participants achieving at least 50% pain relief over four hours compared to placebo, but the evidence is very uncertain (risk ratio (RR) 2.81, 95% confidence interval (CI) 1.80 to 4.37). The number needed to treat for one additional participant to benefit (NNTB) was 2.4 (95% CI 1.8 to 3.7). Low-certainty evidence from 10 studies (914 participants) demonstrates that ketorolac may result in a large increase in the number of participants achieving at least 50% pain relief over six hours compared to placebo (RR 3.26, 95% CI 1.93 to 5.51). The NNTB was 2.5 (95% CI 1.9 to 3.7). Among secondary outcomes, for time to rescue medication, moderate-certainty evidence comparing intravenous ketorolac versus placebo demonstrated a mean median of 271 minutes for ketorolac versus 104 minutes for placebo (6 studies, 633 participants). For the number of participants using rescue medication, very low-certainty evidence from five studies (417 participants) compared ketorolac with placebo. The RR was 0.60 (95% CI 0.36 to 1.00), that is, it did not demonstrate a difference between groups. Ketorolac probably results in a slight increase in total adverse event rates compared with placebo (74% versus 65%; 8 studies, 810 participants; RR 1.09, 95% CI 1.00 to 1.19; number needed to treat for an additional harmful event (NNTH) 16.7, 95% CI 8.3 to infinite, moderate-certainty evidence). Serious AEs were rare. Low-certainty evidence from eight studies (703 participants) did not demonstrate a difference in rates between ketorolac and placebo (RR 0.62, 95% CI 0.13 to 3.03). Ketorolac versus NSAIDs  Ketorolac was compared to parecoxib in four studies and diclofenac in two studies. For our primary outcome, over both four and six hours there was no evidence of a difference between intravenous ketorolac and another NSAID (low-certainty and moderate-certainty evidence, respectively). Over four hours, four studies (337 participants) produced an RR of 1.04 (95% CI 0.89 to 1.21) and over six hours, six studies (603 participants) produced an RR of 1.06 (95% CI 0.95 to 1.19). For time to rescue medication, low-certainty evidence from four studies (427 participants) suggested that participants receiving ketorolac waited an extra 35 minutes (mean median 331 minutes versus 296 minutes). For the number of participants using rescue medication, very low-certainty evidence from three studies (260 participants) compared ketorolac with another NSAID. The RR was 0.90 (95% CI 0.58 to 1.40), that is, there may be little or no difference between groups.   Ketorolac probably results in a slight increase in total adverse event rates compared with another NSAID (76% versus 68%, 5 studies, 516 participants; RR 1.11, 95% CI 1.00 to 1.23; NNTH 12.5, 95% CI 6.7 to infinite, moderate-certainty evidence). Serious AEs were rare. Low-certainty evidence from five studies (530 participants) did not demonstrate a difference in rates between ketorolac and another NSAID (RR 3.18, 95% CI 0.13 to 76.99). Only one of the five studies reported a single serious AE.

AUTHORS' CONCLUSIONS

The amount and certainty of evidence for the use of intravenous ketorolac as a treatment for postoperative pain varies across efficacy and safety outcomes and amongst comparators, from very low to moderate. The available evidence indicates that postoperative intravenous ketorolac administration may offer substantial pain relief for most patients, but further research may impact this estimate. Adverse events appear to occur at a slightly higher rate in comparison to placebo and to other NSAIDs. Insufficient information is available to assess whether intravenous ketorolac has a different rate of gastrointestinal or surgical-site bleeding, renal dysfunction, or cardiovascular events versus other NSAIDs. There was a lack of studies in cardiovascular surgeries and in elderly populations who may be at increased risk for adverse events.

An observational study to evaluate the prescription pattern of analgesics used in the perioperative period in a tertiary care hospital

Background and Aims:

Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage. There are limited observational prescription pattern studies of analgesics in perioperative period in tertiary care hospitals for which this study was carried out in orthopedic, general surgery, and plastic surgery departments. The primary aim was to study the prescription pattern of analgesics in the perioperative period with the secondary aim to study the specific use of opioids and pain relief using the Visual Analog Scale (VAS).

Methods:

A total of 250, 250, and 100 patients were taken from orthopedic, general surgery, and plastic surgery departments, respectively. The analgesics commonly used in preoperative, intraoperative, and postoperative period were observed. The use of opioids in the perioperative period, the number of fixed drug combinations used, the number of generic drug prescription, and pain relief postoperatively were also observed. The analysis was done using descriptive statistics.

Results:

Total analgesics prescribed were 1168, 117, and 369 in orthopedic, general surgery, and plastic surgery departments, respectively, and were maximum in the intraoperative period. Most commonly used analgesic in the preoperative and postoperative period was paracetamol and that in intraoperative period was fentanyl. Nonsteroidal anti-inflammatory drugs (NSAIDs) were mainly prescribed by the general surgery department in postoperative period. The amount of pain in postoperative period after treatment with analgesics was mild to moderate as per the VAS.

Conclusion:

This study revealed that in preoperative and postoperative period, the most common analgesic used is paracetamol. In the intraoperative period, maximum patients received fentanyl. Diclofenac is an established NSAID used in the management of acute and chronic pain states. In our study, we found that the usage of paracetamol was more than NSAIDs and the usage of opioid was maximum during intraoperative period.

Relaxant Action of Diclofenac Sodium on Mouse Airway Smooth Muscle

Diclofenac sodium (DCF) is a nonsteroidal anti-inflammatory drug (NSAID) and is widely used as an analgesic and anti-inflammatory agent. Herein, we found that DCF could relax high K+ (80 mM K+)-/ACh-precontracted tracheal rings (TRs) in mice. This study aimed to elucidate the underlying mechanisms of DCF-induced relaxations. The effects of DCF on airway smooth muscle (ASM) cells were explored using multiple biophysiological techniques, such as isometric tension measurement and patch-clamping experiments. Both high K+- and ACh-evoked contraction of TRs in mice were relaxed by DCF in a dose-dependent manner. The results of isometric tension and patch-clamping experiments demonstrated that DCF-induced relaxation in ASM cells was mediated by cytosolic free Ca2+, which was decreased via inhibition of voltage-dependent L-type Ca2+ channels (VDLCCs), nonselective cation channels (NSCCs), and Na+/Ca2+ exchange. Meanwhile, DCF also enhanced large conductance Ca2+ activated K+ (BK) channels, which led to the relaxation of ASMs. Our data demonstrated that DCF relaxed ASMs by decreasing the intracellular Ca2+ concentration via inhibition of Ca2+ influx and Na+/Ca2+ exchange. Meanwhile, the enhanced BK channels also played a role in DCF-induced relaxation in ASMs. These results suggest that DCF is a potential candidate for antibronchospasmic drugs used in treating respiratory diseases such as asthma and chronic obstructive pulmonary disease.