Performance of the Angle Labor Pain Questionnaire During Initiation of Epidural Analgesia in Early Active Labor.

BACKGROUND: The Angle Labor Pain Questionnaire (A-LPQ) is a new, 22-item multidimensional psychometric questionnaire that measures the 5 most important dimensions of women's childbirth pain experiences using 5 subscales: The Enormity of the Pain, Fear/Anxiety, Uterine Contraction Pain, Birthing Pain, and Back Pain/Long Haul. Previous work showed that the A-LPQ has overall good psychometric properties and performance during early active labor in women without pain relief. The current study assessed the tool's sensitivity to change during initiation of labor epidural analgesia with the standardized response mean (SRM, primary outcome). METHODS: Two versions of the A-LPQ were administered once, in each of 2 test sessions, by the same trained interviewer during early active labor. The sequence of administration was randomized (ie, standard question order version [Test 1] followed by mixed version [Test 2] or vice versa). Test 1 was completed before epidural insertion; Test 2 commenced 20 to 30 minutes after the test dose. Providers assessed/treated pain independently of the study. Sensitivity to change was assessed using SRMs, Cohen's d, and paired t tests. Overall pain intensity was concurrently examined using Numeric Rating Scale and the Verbal Rating Scale (VRS); coping was assessed with the Pain Mastery Scale. Changes in pain were measured with the Patient Global Impression of Change Scale. Internal consistency was assessed with Cronbach's α. Concurrent validity with other tools was assessed using Spearman's rank correlation coefficient. RESULTS: A total of 51 complete datasets were analyzed. Most women reported moderate (63%, 32/51) or severe (18%, 9/51) baseline pain on VRS scores during Test 1; 29% (15/51) reported mild pain, and 6% (3/51) reported moderate pain during Test 2. Approximately 90% (46/51) of women reported much or very much improved pain at the end of testing. Cronbach's α for A-LPQ summary scores was excellent (0.94) and ranged from 0.78 (acceptable) to 0.92 (excellent) for subscales (Test 1). Large SRMs were found for A-LPQ summary scores (1.6, 95% CI: 1.2, 2.1) and all subscales except the Birthing Pain subscale (moderate, 0.60, 95% CI: 0.23, 0.97). Significant (P < .001) differences were found between A-LPQ summary scores and between all subscales on paired t tests. Correlations between A-LPQ summary and Numeric Rating Scale scores (overall pain intensity) were strong (ρ > 0.73), correlations were moderate (ρ > 0.5) with VRS scores and coping scores (ρ > 0.67). CONCLUSIONS: Findings support A-LPQ use for measurement of women's childbirth pain experiences during initiation of labor epidural analgesia during early active labor. Combined with our previous work, they also support the use of the A-LPQ in late labor and at delivery.

High quality labour analgesia using small gauge epidural needles and catheters.

PURPOSE: Inadvertent epidural needle punctures represent the leading cause of severe postdural puncture headache (PDPH) in parturients. Use of small gauge (G) epidural needles for continuous analgesia has received little attention despite possible important reductions in PDPH. We report the first study to examine the feasibility of using small G Tuohy needles and 23 G catheters for labour analgesia. METHODS: Healthy parturients 30 min), recognized dural puncture, PDPH, patient assessment of analgesia within 24 hr of delivery, complications and anesthesiologist satisfaction. RESULTS: Twenty-seven parturients were recruited. Successful blocks were initiated and maintained in 24/27 who rated overall analgesia from good to excellent (19/24 very good to excellent). Three block failures occurred at the initiation phase only (two unilateral, one absent). There was no evidence of catheter kinking after placement. One patient developed PDPH after unrecognized dural puncture which was self-treated with acetaminophen for four days, followed by complete symptom resolution. CONCLUSION: It is feasible to provide high quality labour analgesia using small G epidural needles and catheters. The effect of small G epidural needles on PDPH warrants future study.

A randomized controlled trial examining the effect of naproxen on analgesia during the second day after cesarean delivery.

UNLABELLED: Whereas nonsteroidal antiinflammatory drugs augment spinal morphine on Day l, the analgesia gained by simply combining these drugs with conventional "on request" oral regimens on Day 2 is less clear. In this trial, we randomized 80 women undergoing elective cesarean delivery with spinal morphine (0.2 mg) to receive naproxen (500 mg) or placebo every 12 h after surgery. Both groups received conventional therapy with acetaminophen with codeine (on request) and rescue IM opioids. Incision pain on sitting (IPS), incision pain at rest, uterine cramping, and gas pain were evaluated with visual analog scales (0-100). Worst interval pain (0-10), analgesic use, and side effects were measured over 72 h. At 36 h (primary outcome), naproxen use was associated with reductions in IPS (38.2 +/- 26.0 versus 51.4 +/- 25.7; P = 0.05), incision pain at rest, uterine cramping, and worst interval pain scores. Clinically modest, statistically significant reductions in IPS (P = 0.0001) and opioid use were found over time (P < 0.0l). Reductions in the incidence of inadequate analgesia and improvements in overall pain relief (P = 0.0006) on Day l did not persist on Day 2 (overall pain relief, P = 0.057; inadequate analgesia, 24% naproxen versus 27% controls; P = 1.00). The addition of regular doses of naproxen to conventional oral pain therapy after cesarean delivery leads to reductions in IPS at 36 h and pain over Day 2 but does not reduce the incidence of inadequate analgesia. IMPLICATIONS: This randomized trial suggests that adding regular doses of naproxen to conventional "on request" acetaminophen and codeine therapy provides small reductions in pain on the second day after cesarean delivery. The greatest effects occur at 36 h, when pain peaks.

Dural tissue trauma and cerebrospinal fluid leak after epidural needle puncture: effect of needle design, angle, and bevel orientation.

BACKGROUND: The effects of epidural needle design, angle, and bevel orientation on cerebrospinal fluid leak after puncture have not been reported. The impact of these factors on leak rate was examined using a dural sac model. Dural trauma was examined using scanning electron microscopy. METHODS: Human cadaveric dura, mounted on a cylindrical model, was punctured with epidural needles using a micromanipulator. Tissue was punctured at 15 cm H2O (left lateral decubitus) system pressure, and leak was measured at 25 cm H2O (semisitting) pressure. Leak rates and trauma were compared for the following: (1) six different epidural needles at 90 degrees, bevel parallel to the dural long axis; (2) 18-gauge Tuohy and 18-gauge Special Sprotte epidural needles, 30 degrees versus 90 degrees; (3) 18-gauge Tuohy, bevel perpendicular versus parallel to the dural long axis. RESULTS: With the 90 degrees puncture, bevel parallel, the greatest leak occurred with a 17-gauge Hustead (516 +/- 319 ml/15 min), and the smallest leak occurred with a 20-gauge Tuohy (100 +/- 112 ml/15 min; P = 0.0018). A 20-gauge Tuohy puncture led to statistically significant reductions in leak (P value range, 0.0001-0.0024) compared with all needles except the Special Sprotte. With the 30 degrees versus 90 degrees angle, 30 degrees punctures with an 18-gauge Tuohy produced nonstatistically significant leak reductions compared with the 18-gauge Tuohy at 90 degrees. The puncture angle made no difference for the Special Sprotte. Nonsignificant reductions were found for the Special Sprotte compared with the Tuohy. With the 18-gauge Tuohy bevel orientation, perpendicular orientation produced nonstatistically significant reductions in leak compared with parallel orientation. CONCLUSIONS: Cerebrospinal fluid leak after puncture was influenced most by epidural needle gauge. Leak rate was significantly less for the 20-gauge Tuohy needle.

Epidural catheter penetration of human dural tissue: in vitro investigation.

BACKGROUND: Factors contributing to subarachnoid catheter passage after epidural placement are not well understood. This study explored mechanisms that might explain its occurrence. METHODS: Human cadaveric dura was mounted on a model and pressurized to physiologic levels. In a standardized fashion, a 20-gauge Portex three-port, closed end (nonflexible) tip catheter was passed through an epidural needle mounted on a micromanipulator at a 90 degree angle, attempting to penetrate dura with the catheter. Attempts then followed with a 19-gauge Arrow Flex Tip Plus single-port catheter. Subarachnoid catheter passage was compared in (1) intact dura, (2) clinically occult versus obvious epidural needle punctures, and (3) single 25-gauge Whitacre spinal needle punctures after combined spinal-epidural placement. RESULTS: Neither catheter penetrated intact dura: Portex, 0 of 300 attempts (0.0000; 95% confidence interval [CI]: 0.0000, 0.0158); Arrow, 0 of 300 attempts (0.0000; 95% CI: 0.0000, 0.0158). In clinically occult epidural needle punctures, the 20-gauge Portex catheter penetrated 1 of 3 specimens in 1 of 14 attempts (0.0714; 95% CI: 0.0021, 0.3583). The 19-gauge Arrow did not pass (0 of 15 attempts, 0.0000; 95% CI: 0.0000, 0.2535). In clinically obvious epidural needle punctures, the Portex passed in 6 of 33 attempts (0.1818; 95% CI: 0.0760, 0.3608) and the Arrow passed in 1 of 35 attempts (0.0286; 95% CI: 0.0012, 0.1662). Neither catheter passed through a single 25-gauge spinal needle puncture after an uncomplicated combined spinal-epidural: Portex, 0 of 90 attempts (0.0000; 95% CI: 0.0000, 0.0510); Arrow, 0 of 90 attempts (0.0000; 95% CI: 0.0000, 0.0510). CONCLUSIONS: Catheter passage is unlikely in the presence of intact dura or after an uncomplicated combined spinal-epidural. Unintentional subarachnoid passage suggests dural damage with the epidural needle.