Abstract
The aim of this study was to determine if patients with a previous history of postdural puncture headache (PDPH) might be prone to a new episode after spinal anaesthesia. Consecutive patients (n = 258) who had had surgery under spinal anaesthesia were studied. Of 42 patients with a previous history of PDPH, eight (19.0±) developed a new PDPH episode; whereas out of 216 without a previous history of PDPH, only 15 (6.9±) presented with PDPH. Previous PDPH history indicates a higher chance of a new episode of PDPH after spinal anaesthesia. Women are more susceptible to such recurrences.
Introduction
Headache is a common complication after a spinal puncture performed for the purposes of diagnosis, therapy or spinal anaesthesia (1). The meninges may also be perforated inadvertently during peridural anaesthesia (0.19–4.4% of the time) and cause headache in 50–70% of patients (2).
There are multiple factors that influence the incidence of postdural puncture headache (PDPH): age (more frequent in young people); sex (it predominates in women); puncture with sharp and large calibre needles; and insertion of the needle bezel perpendicularly to dural fibres (3–10).
PDPH may be incapacitating and unpleasant (11–13) and may generate concern for both patient and doctor. If the patient undergoes a second puncture, they might understandably fear that a new PDPH episode might occur. In other words, are those who have experienced PDPH once predisposed to a new PDPH episode if undergoing a second lumbar puncture (LP)?
This study aimed to evaluate if patients with a history of PDPH might be prone to a new episode after a dural puncture for spinal anaesthesia.
Methods
In the period May 2005 to May 2006, 258 consecutive patients of both sexes were prospectively studied. All had had previous surgery, which had occurred >12 months previously under spinal anaesthesia and in which spinal anaesthesia had been used as an anaesthetic technique. All patients were submitted to a new surgical procedure (abdominal, urological, gynaecological, vascular or orthopaedic surgery), under spinal anaesthesia, with Quincke 25-G or 27-G needles with the bezel parallel to the longitudinal axis of the dural sack. Patients with neurological disease, obstetrical surgery and gestation in course were excluded.
Two groups of patients were studied: 42 with a previous history of PDPH and 216 without such a history.
PDPH was diagnosed when the headache was postural, i.e. worsened in the upright position and was relieved in the horizontal position, and appearing within the first 5 days after an LP. This is in accordance to the revised classification criteria of the International Headache Society (ICHD-II) (14). The study was prospective regarding outcome, namely PDPH or no PDPH after a second LP. The interviewer was blinded to the outcome of the first LP. The patients were asked if they had experienced headaches with the characteristics of PDPH at the first LP.
Patients were visited at the first postoperative day and the presence of headache with the characteristics of PDPH was investigated. A personal phone contact was kept until the fifth day after the dural puncture, or longer if PDPH was present. In those patients where PDPH was diagnosed, the following was registered: age, sex, needle calibre, number of puncture attempts, time interval between LP and the beginning of symptoms, the duration, location and intensity of pain in conformity to visual analogue scale (0–10) criteria, associated symptoms and signs and the interval between spinal anaesthesia in years.
All patients gave written consent to participate in the study, which was approved by the Ethics Committee of the respective Institutions.
Data are shown as mean ± SD. The χ2 test and Student t-test were used, when applicable, to analyse the results and a significant difference in the statistical test was considered when P < 0.05.
Results
The demographic data are shown in Table 1. As expected, in the group with a positive history of PDPH there was a predominance of women, since women have a higher chance to develop this particular type of headache (7). There were no significant differences in age. Likewise, there was no difference in the type of needle used between the studied groups—both sizes of needles (27-G and 25-G needle) were used in both groups. However, the former was used with a slightly higher frequency compared with the latter in the PDPH group (64% vs. 54%; P > 0.05, χ2 test). The use of the smaller size of needle doubtless made patients less susceptible to PDPH.
Demographic data and needle size for patients with a history of previous postdural puncture headache (PDPH) and for those without
Student's t-test.
χ2 test.
The study showed that patients with a past history of PDPH were statistically more prone to develop a new PHDH after a second spinal anaesthesia (P = 0.0118; χ2 test). Of 42 patients with a previous history of PDPH, eight (19.0%) developed a new PDPH episode; whereas of 216 without a previous history of PDPH, only 15 (6.9%) patients presented with PDPH (Table 2). The risk of a new PDPH episode in patients with a previous history was 2.7 times higher than in those without. The male group was too small to be analysed separately, but was shown that women with a past history of PDPH were more prone to develop a new PDPH than those without (24.2% vs. 10.6%; P = 0.045). The eight patients with a previous history of PDPH developing a new episode of PDPH after a second LP were all women aged 31–61 years (45.3 ± 10.5 years). The referred time interval between the last and the current PDPH episode varied from 2 to 21 years (11.5 ± 7.4 years). Two patients experienced PDPH in three consecutive spinal anaesthesia procedures.
Postdural puncture headache (PDPH) prevalence in patients with and without a previous history of PDPH
P = 0.0452 in the χ2 test vs. the group of women without PDPH previous history.
P = 0.0118 in the χ2 test vs. the group of both gender without PDPH previous history.
Discussion
This study has demonstrated that a previous history of PDPH is a risk factor for a new episode of PDPH. The previous history of PDPH as a risk factor for a new PDPH episode has been addressed in one study by Lybecker and collaborators (15). In this context, in a prospective study (15) with 1021 spinal anaesthesias 117 patients were identified to have already undergone spinal anaesthesia. In the first intervention, three patients out of the 117 had a previous history of PDPH, whereas after the second intervention two of three (66.6%) suffered a new PDPH. In contrast, just three out of 114 (2.8%) who did not present PDPH after the first intervention presented PDPH for the first time after the second spinal anaesthesia. Despite the relatively small number of patients, these authors considered a previous history of PDPH as a prognosis factor for a new episode of PDPH (15). This has also been claimed in casuistic reports (16–18), but no controlled studies have been conducted.
In the pathophysiology of postural headache, it is likely that mechanical factors induced by altered cerebrospinal fluid (CSF) hydrodynamics play a role. One of the major functions of the CSF is the mechanical protection of the brain and the spinal cord from (i) potentially injurious blows to the internal structure of the skull and spinal column, and (ii) acute changes in venous pressure. Because of buoyancy phenomena, a 1500-g brain would weigh only 50 g when suspended in CSF (19). Hence, a relatively constant relationship between the volume and pressure of the CSF compartment is imperative for the integrity of the central nervous system. As a result, when the individual assumes an upright posture, in a situation of significant low volume, the CSF migrates, by gravity, into the spinal dural sack. This, in turn, causes loss of buoyancy supporting the brain. Consequently, the brain sags, and tension on the meninges and other intracranial structures (i.e. vessels and nerves) triggers the pain observed in PDPH.
Furthermore, in an attempt to compensate for the loss of intracranial CSF volume, venous vasodilation occurs. This compensatory venodilation, consequent upon the loss of CSF, is explained by the Monro–Kellie hypothesis, i.e. as a result of the decrease in intracranial CSF volume, there is a compensatory increase in blood volume, since the intracranial content (CSF plus blood plus nervous parenchyma) must be constant in volume. Thus, much of the pain in a PDPH would be related to vascular distention. This process reverses itself when a supine posture is assumed. In this regard, perivascular sensory nerves surrounding the intracranial veins and sinus react to vascular distention with increased firing. Experimental evidence has shown that activation of the trigeminovascular system is induced by mechanical distention of the superior sagittal sinus in cats (20).
Another interesting fact is that recurrent episodes of PDPH have been present only in women in our series, despite the presence of 112 men enrolled in the study. Common hypotheses for the increased susceptibility of women to PDPH are: (i) young women may be at greater risk because of increased dural fibre elasticity, which could maintain a patent dural defect better than a less elastic dura (1); and (ii) oestrogens might increase substance P receptor sensitivity (21). One may also speculate that besides the psychological and hormonal aspects (22), one factor to explain the female susceptibility to recurrent PDPH is gender difference in the brain–skull–vertebral canal morphology (23), particularly at the craniospinal junction.
In conclusion, this study has demonstrated that a history of previous PDPH indicates a higher chance of a new episode of PDPH after spinal anaesthesia. Our data suggest that certain individuals are predisposed to PDPH and women are more susceptible to recurrences of PDPH.