Reply

Abstract

Dear Sir, We are grateful to you for having given us the opportunity to answer to comments made by Alici et al. in response to our article published in Acta Obstetricia et Gynecologica Scandinavica(1). All the authors agree with Alici et al. that epidural blood patch (EBP) offers significant benefits in treating postdural puncture headache (PDPH). However we strongly disagree with their suggestion that EBP should be an early first-line management in treating PDPH. In one of the largest studies on PDPH (sample size of 527 patients over 12 years), EBP was performed after a median delay of 4 days after dural puncture (2). In this study it was observed that failure of EBP was significantly increased when EBP was performed within 3 days after dural puncture as the severity of CSF leak was high during the first few days. The excessive CSF leakage prevents the blood patch from sealing the dural hole. This is contrary to Alici et al.'s advocation for urgent EBP as soon as PDPH is diagnosed. Furthermore, EBP is not without its share of other complications like transient bradycardia (mean of 51.3 beats/min from a baseline of 88.6 in a sample size of 10 PDPH cases) (3), backache (develops within 48 h in 35% EBP patients and persists in 16% for a mean duration of 27 days) (4), cauda equina syndrome (5), and cerebral ischemia (6) to mention a few. A relatively recent survey of North American academic centers of the management of dural puncture occurring in obstetrical patients (basically USA & Canada) has reported the use of prophylactic EBP in only 37% of centers (7). In the same survey, 86% of centers reported EBP failure and 44% reported persistent PDPH even after 2 or more EBP. The degree of optimism shown by Alici et al. may be unwarranted as the incidence of incomplete cure obtained by EBP obtained over a four-week follow-up may be as high as 36% (8, 9). PDPH is distressing to a nursing mother, especially if she is confined to bed with minimal permitted movement. Current data suggest that there is no prophylactic role for forced bed rest after accidental dural puncture or routine spinal (7). However after PDPH occurs, recumbency aids in pain relief but the mother's movement need not be unduly restricted in bed. All our PDPH patients on methergine therapy were encouraged to nurse their babies in bed without actually standing or walking in the room. All our patients gladly accepted and followed this advice. We are at a loss to understand the comment by Alici et al. that the PDPH patient is angry, resentful, and has difficulty in communicating with other family members. This may be true if the patient's problem is not attended to sympathetically and steps taken fail to alleviate it. We agree with Alici et al. that the PDPH is most likely due to leakage of CSF through the dural hole or is secondary to reflex cerebral vasodilatation (10). The former mechanism is the most likely cause when the dural tear is made by the larger gauge (16–18 gauge) epidural needle. We too advocate EBP to treat PDPH secondary to inadvertent dural hole by large gauge epidural needle, if there is no response to conservative treatment over 24–48 h. In this situation, PDPH is usually severe and EBP is required to seal the large dural hole. However, in all our 25 patients, PDPH followed dural hole made by a 25 or 26 gauge Quincke's spinal needle. It is unlikely that excessive CSF leakage through the hole made by this narrow gauge spinal needle was the predominant cause of PDPH in our patient. In these patients, the predominant factor is likely to be the vascular theory – thus the greater suitability of using methergine instead of EBP. Lastly, our results should not be seen as a success story of just 16% as stated twice in the comments by Alici et al. In fact we had just one treatment failure (4%). In the remaining 80% patients, the actual VAS score (VAS, 1 = no headache, 10 = maximum headache experienced by them) was 4.1±0.7 with a range of 2–5 as assessed over the first 24 h after instituting methergine therapy. By the third day, all of these 80% patients had complete relief from PDPH. These results are no less good than those achieved with EBP. Above all, methergine therapy is a noninvasive modality, which is not associated with any serious morbidity as those encountered with EBP (outlined above).