Pain and Analgesia During Labor and Delivery Between 16 0/7 and 22 6/7 Weeks of Gestation.

OBJECTIVE: To describe severity of pain during labor at previable estimated gestational age and to determine the effectiveness of various methods of analgesia in this population. METHODS: In this retrospective review of the records of women undergoing induction or augmentation of labor between 16 0/7 and 22 6/7 weeks of gestation, we examined pain scores (numeric rating scale 0-10) documented throughout labor and analgesia method (none, systemic, or neuraxial). We compared relevant patient and labor characteristics such as gestational age, fetal weight, time interval from induction to delivery as well as pain data including analgesia type and pain scores before and after analgesia. We compared analgesia response in patients who received neuraxial analgesia and those who did not. RESULTS: A total of 80 patients met inclusion criteria: four requested no analgesia, 56 used systemic analgesia only, 11 used systemic analgesia initially and then requested neuraxial analgesia, and nine used neuraxial without using systemic analgesia first. Median peak pain score was 7 among all patients. Patients who chose neuraxial analgesia had higher estimated gestational age (21 compared with 20 weeks of gestation, P=.03), fetal weight (362 compared with 268 g, P=.047), and admission-to-delivery time intervals (19.25 compared with 10.3 hours, P=.003) than those who chose no or systemic analgesia. Immediate preanalgesia peak pain scores were not different between groups, but patients who received neuraxial analgesia had lower immediate postanalgesia nadir scores than those who chose systemic pain relief. CONCLUSION: Pain during induction of labor at previable gestational ages may be greater than is commonly appreciated. Neuraxial analgesia may provide more optimal pain relief for patients with higher estimated gestational age and fetal weight, particularly after 22 weeks of estimated gestational age.

Adaptive force sonorheometry for assessment of whole blood coagulation.

BACKGROUND: Viscoelastic diagnostics that monitor the hemostatic function of whole blood (WB), such as thromboelastography, have been developed with demonstrated clinical utility. By measuring the cumulative effects of all components of hemostasis, viscoelastic diagnostics have circumvented many of the challenges associated with more common tests of blood coagulation. METHODS: We describe a new technology, called sonorheometry, that adaptively applies acoustic radiation force to assess coagulation function in WB. The repeatability (precision) of coagulation parameters was assessed using citrated WB samples. A reference range of coagulation parameters, along with corresponding measurements from prothrombin time (PT) and partial thromboplastin time (PTT), were obtained from WB samples of 20 healthy volunteers. In another study, sonorheometry monitored anticoagulation with heparin (0-5 IU/ml) and reversal from varied dosages of protamine (0-10 IU/ml) in heparinized WB (2 IU/ml). RESULTS: Sonorheometry exhibited low CVs for parameters: clot initiation time (TC1), <7%; clot stabilization time (TC2), <6.5%; and clotting angle (theta), <3.5%. Good correlation was observed between clotting times, TC1 and TC2, and PTT (r=0.65 and 0.74 respectively; n=18). Linearity to heparin dosage was observed with average linearity r>0.98 for all coagulation parameters. We observed maximum reversal of heparin anticoagulation at protamine to heparin ratios of 1.4:1 from TC1 (P=0.6) and 1.2:1 from theta (P=0.55). CONCLUSIONS: Sonorheometry is a non-contact method for precise assessment of WB coagulation.