Daily Anesthesiology Research Analysis
Three randomized clinical trials inform perioperative anesthesia practice: intrathecal hydromorphone was noninferior to morphine for post-cesarean analgesia; prophylactic intravenous calcium gluconate during intrapartum cesarean under spinal anesthesia reduced postpartum blood loss and additional uterotonic use; and intercostal cryoanalgesia did not improve acute pain after VATS and was associated with higher cough pain at 1 month.
Summary
Three randomized clinical trials inform perioperative anesthesia practice: intrathecal hydromorphone was noninferior to morphine for post-cesarean analgesia; prophylactic intravenous calcium gluconate during intrapartum cesarean under spinal anesthesia reduced postpartum blood loss and additional uterotonic use; and intercostal cryoanalgesia did not improve acute pain after VATS and was associated with higher cough pain at 1 month.
Research Themes
- Obstetric anesthesia: optimizing neuraxial opioid strategies and hemorrhage mitigation
- Perioperative multimodal analgesia: evaluating novel regional/adjunct techniques
- Practice-changing trials and the value of negative RCTs
Selected Articles
1. Intrathecal Hydromorphone Versus Intrathecal Morphine for Postcesarean Delivery Analgesia: A Randomized Noninferiority Trial.
In 126 elective cesarean patients, intrathecal hydromorphone 75 µg was noninferior to morphine 150 µg for 24-hour pain (mean difference -0.46; 95% CI -1.0 to 0.1). Opioid consumption, quality of recovery (ObsQoR-11), time to first opioid, and pruritus/nausea interventions were similar, with no neonatal differences.
Impact: Addresses opioid selection in cesarean spinal anesthesia using a rigorous noninferiority RCT, supporting hydromorphone as a viable alternative during shortages or intolerance to morphine.
Clinical Implications: Intrathecal hydromorphone 75 µg can substitute for morphine 150 µg for post-cesarean analgesia without compromising pain control or recovery metrics, informing formularies and protocols during drug shortages or patient-specific intolerance.
Key Findings
- Hydromorphone 75 µg was noninferior to morphine 150 µg for 24-hour mean NRS pain after cesarean (difference -0.46; 95% CI -1.0 to 0.1).
- No significant differences in 24-hour oral morphine equivalents, ObsQoR-11, time to first opioid, or pruritus/nausea interventions.
- Neonatal outcomes (Apgar scores) were comparable between groups.
Methodological Strengths
- Randomized, blinded noninferiority design with prespecified margin.
- Use of established ED90 dosing and multiple clinically relevant secondary outcomes.
Limitations
- Primary pain outcome was recall-based at 24 hours, introducing potential recall bias.
- Moderate sample size and elective cesarean population may limit generalizability to higher-risk patients.
Future Directions: Multicenter trials to confirm findings across diverse populations, standardized dosing/monitoring protocols, and evaluation of maternal side effects, breastfeeding outcomes, and rare adverse events.
2. Effect of prophylactic intravenous calcium gluconate on uterine atony during intrapartum cesarean delivery with spinal anesthesia: a placebo controlled, randomized clinical trial.
Among 367 intrapartum cesarean patients, prophylactic calcium did not improve obstetrician-rated uterine tone change from baseline, but reduced postpartum blood loss by 55.6 mL (95% CI 24.3–86.8; P=0.001) and halved additional uterotonic use (21.7% vs 42.39%; RR 0.51; 95% CI 0.37–0.71). Transfusion and vasopressor needs were similar.
Impact: A large, blinded RCT in a high-risk obstetric setting suggests a simple, low-cost intervention may reduce blood loss and uterotonic needs despite a negative primary tone outcome.
Clinical Implications: For intrapartum cesarean under spinal anesthesia, 1 g IV calcium gluconate after cord clamping may be considered to reduce blood loss and additional uterotonic administration. Implementation should weigh subjective tone assessment and unchanged transfusion outcomes.
Key Findings
- No significant improvement in obstetrician-rated uterine tone change from baseline (P=0.11).
- Lower postpartum blood loss with calcium (526.0 ± 155.2 vs 581.5 ± 148.9 mL; mean difference 55.6 mL; 95% CI 24.3–86.8; P=0.001).
- Reduced need for additional uterotonics (21.7% vs 42.39%; RR 0.51; 95% CI 0.37–0.71; P=0.001), with similar transfusion and vasopressor requirements.
Methodological Strengths
- Prospective, randomized, placebo-controlled, blinded design with adequate sample size.
- Prospectively registered trial with clinically meaningful secondary endpoints.
Limitations
- Primary outcome (uterine tone score) was subjective and operator-assessed.
- Single-country setting; transfusion outcomes did not differ despite reduced blood loss.
Future Directions: Multicenter trials to validate findings, explore dosing/timing, and assess high-risk atony populations with standardized, objective uterine contractility metrics and clinically hard endpoints.
3. Intercostal cryoanalgesia for acute pain after video-assisted thoracic surgery lung resection: A randomized controlled preliminary trial.
Intercostal cryoanalgesia added to standard multimodal analgesia with paravertebral block did not reduce 24-hour cough pain after VATS (4.7 ± 2.7 vs 4.8 ± 2.9; P=0.78), nor improve acute recovery metrics up to 7 days. Cough pain was higher at 1 month in the cryo group (4.7 ± 2.4 vs 3.4 ± 2.0; P=0.036), with no differences at 3 or 6 months.
Impact: A double-blind RCT provides high-quality negative evidence against routine intercostal cryoanalgesia as an adjunct after VATS, potentially averting adoption of an ineffective (and possibly harmful at 1 month) intervention.
Clinical Implications: Do not routinely add intercostal cryoanalgesia to single-shot paravertebral-based multimodal analgesia after VATS lung resection; focus on optimizing regional techniques and systemic multimodal strategies with proven benefit.
Key Findings
- No difference in 24-hour cough pain between cryoanalgesia and control (4.7 ± 2.7 vs 4.8 ± 2.9; P=0.78).
- No improvements in acute recovery measures (opioid consumption, side effects, QoR) up to 7 days; sensory loss and DN4 neuropathic scores were comparable.
- Higher cough pain at 1 month in cryo group (4.7 ± 2.4 vs 3.4 ± 2.0; P=0.036), with no differences at 3 and 6 months.
Methodological Strengths
- Randomized, double-blind, controlled design with active multimodal analgesia in both groups.
- Longitudinal assessment up to 6 months with validated pain and neuropathic measures.
Limitations
- Preliminary sample size (n=80) limits power for rare adverse events and subgroup analyses.
- Single-procedure context (VATS lobectomy) may limit generalizability to other thoracic procedures.
Future Directions: Further trials should evaluate different cryo parameters, patient selection, and compare against continuous regional techniques; investigate mechanisms underlying increased 1-month cough pain.