Dexmedetomidine nebulization: an answer to post-dural puncture headache?

Comparative evaluation of nebulised dexmedetomidine vs fentanyl for the treatment of post-dural puncture headache (PDPH) in parturients after caesarean section under spinal anaesthesia: A randomised controlled study

Background and Aims

The incidence of post-dural puncture headache (PDPH) following spinal anaesthesia in the obstetric population is around 0.5%-2%. Hydration, bed rest, caffeine, paracetamol, non-steroid anti-inflammatory drugs, epidural blood patches, etc., are the various modalities used for its management. This study aims to compare nebulised dexmedetomidine versus fentanyl for the treatment of PDPH in parturients after caesarean section under spinal anaesthesia.

Methods

Ninety obstetric patients aged 18-35 years with American Society of Anesthesiologists (ASA) physical status II/III and suffering from PDPH as per the criteria of the International Headache Society after caesarean section under spinal anaesthesia were recruited in this double-blinded randomised study. Patients were randomised to Group D (dexmedetomidine 1 µg/kg nebulisation), Group F (fentanyl 1 µg/kg nebulisation), and Group S (saline nebulisation 4mL). The nebulisation was done 12 hourly for 72 hours. Assessment parameters included pain score and the requirement of additional treatment such as paracetamol, caffeine, and epidural blood patch. Analysis of variance test was used for continuous quantitative variables, and the Kruskal-Wallis test was used for quantitative discrete data.

Results

The pain scores at 1, 6, 12, 24, 48, and 72 hours following nebulisation were significantly lower in Group D in comparison to groups F and S (P < 0.001). The number of patients requiring additional analgesic therapy was lower in Group D in comparison to patients in other groups (P < 0.001).

Conclusion

Dexmedetomidine nebulisation resulted in effective reduction in PDPH symptoms and pain scores. Nebulisation with fentanyl did not alleviate PDPH symptoms when compared to the control group.

Nebulized dexmedetomidine versus neostigmine/atropine for treating post-dural puncture headache after cesarean section: a double-blind randomized controlled trial

BACKGROUND

Post-dural puncture headache (PDPH) is one of the most common complications of neuraxial anesthesia after an accidental dural puncture. This study aimed to test non-interventional alternatives to treat PDPH. Our goals were to compare the effectiveness of nebulized dexmedetomidine (DEX) versus neostigmine/atropine in the conservative management of PDPH.

METHODS

A randomized double-blind controlled study of ninety (90) women divided into three equal groups: group C (given nebulization of saline 0.9% placebo in four mL), group N (given nebulization of 20 µ/kg neostigmine and 10 µ/kg atropine diluted in four mL normal saline), and group D (given nebulization of dexmedetomidine 1 µg/kg diluted in four mL normal saline). Nebulization was done twice daily for three days, and a Visual Analogue Scale pain score (VAS) was recorded for seventy-two hours after the intervention for the three groups with a VAS Score equal or less than three being the cutoff value.

RESULTS

VAS was significantly decreased in dexmedetomidine, and neostigmine/atropine groups compared to the control group at six hours (median VAS: 5, 2, and 2 for groups C, N, and D respectively [P=0.001]). There was a significant difference in VAS trends between the three groups (at six, twelve, twenty-four, thirty-six, and forty-eight hours [P=0.001], and at seventy-two hours [P=0.003]). No patients in group D, but one patient in group N and seven patients in group C needed an epidural blood patch.

CONCLUSIONS

Nebulized dexmedetomidine and neostigmine/atropine had a rapid effect on relieving PDPH after cesarean section.

Postdural Puncture Headache-Risks and Current Treatment

PURPOSE OF REVIEW

This manuscript aims to review the risks and the current treatments for postdural puncture headache (PDPH).

RECENT FINDINGS

PDPH is a relatively frequent complication after neuraxial blocks. It is typically orthostatic in nature, presenting as a positional and dull aching or throbbing headache, with added dysregulation of auditory and/or visual signals. Certain characteristics, such as female sex and young age, may predispose patients to the development of PDPH, as may factors such as previous PDPH, bearing down during the second stage of labor, and the neuraxial technique itself. Long-term complications including chronic headache for years following dural puncture have brought into question of the historical classification of PDPH as a self-limiting headache. So far, the underlying mechanism governing PDPH remains under investigation, while a wide variety of prophylactic and therapeutic measures have been explored with various degree of success. In case of mild PDPH, conservative management involving bed rest and pharmacological management should be used as first-line treatment. Nerve blocks are highly efficient alternatives for PDPH patients who do not respond well to conservative treatment. In case of moderate-to-severe PDPH, epidural blood patch remains the therapy of choice. An interdisciplinary approach to care for patients with PDPH is recommended to achieve optimal outcomes.

Effectiveness of nebulized dexmedetomidine for treatment of post-dural puncture headache in parturients undergoing elective cesarean section under spinal anesthesia: a randomized controlled study

PURPOSE

The need for effective treatment for post-dural puncture headache (PDPH) is a growing research entity. This study aimed to test the effectiveness of additional dexmedetomidine (DEX) to PDPH conservative management and evaluate its cerebral hemodynamic effects trans-cranial Doppler.

METHODS

This prospective randomized double-blind controlled trial was conducted on 43 post-partum females suffering from PDPH with visual analog score (VAS) ≥ 4 and Lybecker score ≥ 2. The study subjects were allocated into control group [n = 22] received nebulization of 4 mL 0.9% saline and DEX group [n = 21] received nebulization of 1 µg/kg DEX diluted in 4 mL 0.9% saline twice daily that was continued until achieving VAS score ≤ 3 and Lybecker score < 2 and/or for a maximum of 72 h. Both groups received routine conservative management. The primary outcome was the VAS and Lybecker scores and the secondary results were the DEX effects on cerebral vessels and the occurrence of any adverse effects.

RESULTS

VAS and Lybecker scores were significantly lower in DEX group. The middle cerebral artery mean flow velocity was significantly lower, and the pulsatility index was considerably higher after DEX nebulization compared to placebo. Two patients in the control group were indicated for epidural blood patch.

CONCLUSION

The addition of DEX nebulization (1 µg/kg twice daily) to the PDPH conservative care effectively relieved the symptoms and lowered pain scores which could be due to its analgesic and cerebral vasoconstrictive effects.

TRIAL REGISTRATION

This study was approved by the research ethical committee of Faculty of Medicine, Zagazig University with the reference number (ZU-IRB#: 6075/26-4-2020) and it was registered under clinicaltrials.gov (NCT04327726).