Risk of Postdural Puncture Headache in Adolescents and Adults.

BACKGROUND: Spinal anesthesia is known to have numerous benefits, including reductions in nausea and opioid consumption; however, postdural puncture headache (PDPH) remains a significant risk associated with this technique. The literature specifically examining this complication in adolescents is scarce. Our primary objective was therefore (1) to estimate the incidence of PDPH with a 27G pencil-point needle in patients between the ages of 12 and 19 undergoing ambulatory lower extremity procedures and (2) to compare it to the incidence in adults aged 20-45 years. METHODS: After institutional review board (IRB) approval, patients aged 12-45 years undergoing ambulatory lower extremity surgery were approached. Patients undergoing the procedure under combined spinal-epidural (CSE) or spinal anesthesia with a 27G pencil-point needle were eligible for enrollment. Patients were consented before surgery and received a survey via e-mail on postoperative day (POD) 4 inquiring about the presence of a headache. Each headache was described by the participant and assessed for severity, time of onset, duration, location, and whether it was of a postural nature. All patients reporting a postural headache were contacted by a physician author to confirm a diagnosis of PDPH using the International Headache Society diagnostic criteria. RESULTS: A total of 656 patients were included in the analysis. Overall, 3.4% of patients developed PDPH. The percentage developing PDPH was 4.9% (3.0-7.8) among those aged 12-19 years and 1.8% (0.8-3.9) in the 20- to 45-year-old group. After adjusting for covariates, the age group between 12 and 19 years was associated with an almost 3-fold increase in the odds (2.8 [95% confidence interval {CI}, 1.1-7.3]) for the development of PDPH compared to that in the 20-45 age group. One patient in the adult group required an epidural blood patch. CONCLUSIONS: The overall incidence for the development of PDPH in ambulatory patients <45 years of age is low. However, the odds for developing PDPH is significantly higher in teenagers compared to those aged 20-45 years. This increase was not associated with an increase in the need for an epidural blood patch. Providers may incorporate these data in their consent process and have a higher index of suspicion for PDPH in teenagers who report headaches after neuraxial anesthesia.

Complications in Pediatric Regional Anesthesia: An Analysis of More than 100,000 Blocks from the Pediatric Regional Anesthesia Network.

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Complications in pediatric regional anesthesia are rare, so a large sample size is necessary to quantify risk. The Pediatric Regional Anesthesia Network contains data on more than 100,000 blocks administered at more than 20 children's hospitals. This study analyzed the risk of major complications associated with regional anesthesia in children. METHODS: This is a prospective, observational study of routine clinical practice. Data were collected on every regional block placed by an anesthesiologist at participating institutions and were uploaded to a secure database. The data were audited at multiple points for accuracy. RESULTS: There were no permanent neurologic deficits reported (95% CI, 0 to 0.4:10,000). The risk of transient neurologic deficit was 2.4:10,000 (95% CI, 1.6 to 3.6:10,000) and was not different between peripheral and neuraxial blocks. The risk of severe local anesthetic systemic toxicity was 0.76:10,000 (95% CI, 0.3 to 1.6:10,000); the majority of cases occurred in infants. There was one epidural abscess reported (0.76:10,000, 95% CI, 0 to 4.8:10,000). The incidence of cutaneous infections was 0.5% (53:10,000, 95% CI, 43 to 64:10,000). There were no hematomas associated with neuraxial catheters (95% CI, 0 to 3.5:10,000), but one epidural hematoma occurred with a paravertebral catheter. No additional risk was observed with placing blocks under general anesthesia. The most common adverse events were benign catheter-related failures (4%). CONCLUSIONS: The data from this study demonstrate a level of safety in pediatric regional anesthesia that is comparable to adult practice and confirms the safety of placing blocks under general anesthesia in children.

Post-Dural Puncture Headache is Uncommon in Young Ambulatory Surgery Patients.

BACKGROUND: The incidence of post-dural puncture headache (PDPH) arising from spinal anesthesia in the general population is low. However, patients under 45 years have been shown to exhibit a higher incidence of PDPH, even with small needles. QUESTIONS/PURPOSES: This study aimed to estimate the incidence of PDPH from a 27G pencil-point needle in ambulatory surgery patients between the ages of 15-45 years and compare incidence of PDPH by age group, sex, and history of headache. METHODS: In this prospective cohort study, 300 patients (15-45 years old) who underwent simple knee arthroscopy under spinal anesthesia with a 27G pencil-point needle were enrolled. Verbal consent was obtained during the initial phone conversation between post-operative days (PODs) 2-5. A PDPH questionnaire was administered during this conversation and between PODs 7-10. Patients who reported a positional headache were contacted by a physician co-investigator, who determined PDPH diagnosis. RESULTS: Five patients were excluded from analysis due to complicated operative procedures or spinal needle size. The overall PDPH incidence was 2.0% (95% CI 0.9-4.4; 6/295). PDPH incidence in 15-19-year-old patients was 16.7% (95% CI 4.7-44.8; 2/12). The crude relative risk of PDPH was 15.4 (95% CI 2.8-114.4) for patients with and without history of headache and 2.5 (95% CI 0.5-14.8) for females vs. males. Overall, 16.3% (95% CI 12.5-20.9) of patients reported post-operative, non-positional headaches. CONCLUSIONS: There was a low overall incidence of PDPH among patients aged 15-45. Pre-planned subgroup analyses of PDPH incidence by age group revealed a high risk of PDPH among a small sample of 15-19-year-olds.

Molecular genetic characterization of the distal NKC recombination hotspot and putative murine CMV resistance control locus.

The NK gene complex (NKC) controls murine cytomegalovirus (MCMV) immunity through Cmv1-dependent natural killer (NK) cell responses. Ly49H expression correlates with Cmv1 phenotypes in different inbred strains, is required for MCMV resistance in C57BL/6 (B6) mice, and its interaction with the MCMV encoded m157 protein leads to NK cell-mediated destruction of virus-infected cells. However, genetic mapping studies have previously indicated that Cmv1 should reside in the D6Wum9-16 NKC interval, distal to Ly49h. Since these data suggested that multiple NKC-linked loci could regulate viral immunity, a putative MCMV resistance control ( Mrc) locus was pinpointed to within the D6Wum9-16 interval on a NKC-aligned bacterial artificial chromosome (BAC). Sequence analysis of BAC 151 revealed several novel G-protein coupled receptor genes, an HMG-1 remnant and many additional polymorphic microsatellites that were useful in determining the minimal genetic interval for the Mrc locus. Moreover, comparison of B6, BALB/c, A/J and recombinant Mrc alleles restricted the genetic interval to approximately 470 bp and showed that it was also a hotspot for recombination. MCMV challenge of novel NKC recombinant mice demonstrated that Mrc(B6) was not required for MCMV resistance nor could it directly complement the Ly49(BALB) haplotype to rescue MCMV susceptibility. Taken together, these data show that while Mrc apparently guides recombination, Ly49H expression is sufficient for MCMV resistance in B6 mice. A direct role for Mrc(B6) in virus resistance is excluded in the novel mice.