A 57-patient sample was analysed, 24 (42.1%) males and 33 (57.9%) females with a mean age of 55 ± 16.2 years. Mean weight was 81.4 ± 23.7 kg, mean height 167.6 ± 7.2 cm, and average BMI 29.04 ± 8 kg/m2. Eight (14%) of the patients had undergone a lumbar puncture on a previous occasion.

A total of 24 patients had a history of headache (42.1%), of which 9 (37.5%) presented episodes compatible with tension headache, 2 (8.3%) migraine, 2 (8.3%) of them presented episodes of tension headaches and migraine episodes, and 5 (20.8%) mixed headache (tension headache with some characteristics of migraines during episodes such as: associated nausea, worsening during physical activity, or throbbing). Therefore, 9 patients (37.5) experienced headache with a migraine component. One patient (4.2%) presented orthostatic headache (suspected low CSF pressure), 3 patients (12.5%) headache compatible with idiopathic intracranial hypertension (normal imaging study), and in 2 patients (8.3%) the headache could not be classified due to non-specific characteristics, low frequency, and a case history that was difficult to classify the type of headache according to the IHS-II.

Regarding vascular risk factors, arterial hypertension and dyslipidaemia were the most common risk factors, present in 36.8% (21) and 29.8% of the patients, respectively. Eight patients (14%) had diabetes mellitus diagnoses and three (5.3%) hyperuricaemia. A total of 29.8% of the patients were active smokers at the time of the procedure, with mean intake of 10.4 ± 7.4 cigarettes per day. Four patients (3.5%) consumed alcohol on a daily basis. A history of cancer was confirmed in 4 patients (7.0%) (2 breast cancer, 1 lung cancer, and 1 follicular lymphoma). Three patients (5.3%) had histories of inflammatory/autoimmune diseases: psoriasis, ulcerative colitis, and rheumatoid arthritis. Three patients (5.3%) had fibromyalgia diagnoses and 4 (7%) of the patients had anxiety–depressive disorder.

Post-lumbar puncture headache occurred in 28 patients (49.1%). In 22 of those (38.6), the headache was orthostatic in nature, compatible with post-dural puncture headache (PDPH) (Fig. 1).

Figure 1.

Porcentaje de pacientes con cefalea tras la realización de la punción lumbar.

(0.11MB).

Table 1 shows the data stratified by presence or absence of PDPH. It is worth noting that there was a larger proportion of females (48.5%) versus males (25%) in the PDPH group. The mean age of the patients who presented PDPH (49.4 years) was lower than that of the patients who did not present with headache (58.5 years). Of the 24 patients with a medical history of headache, 14 (58.3%) presented PDPH versus 8 (24.2%) of the patients without a history of headache (p = 0.013). No differences were observed between the types of prior headache and the appearance of PDPH. Nor was a relationship observed between the different vascular risk factors or the other medical history recorded and the onset of PDPH.

The indications for performing a lumbar puncture were: in 16 patients (24.6%) to perform CSF oligoclonal banding, in 27 (47.3%) to measure CSF biomarkers for Alzheimer's disease (patients with suspected mild cognitive decline, GDS < 3), and 4 patients (7%) were undergoing neuromuscular pathology testing. In 4 of the patients (7%) the lumbar puncture was performed to measure intracranial pressure (ICP). The remaining 8 patients (14%) had other indications: suspicion of meningeal carcinomatosis, confusional syndrome, temporary vision loss, isotope cisternography, suspicion of meningitis, idiopathic intracranial hypertension, determination of JC virus, and suspicion of autoimmune encephalitis. No differences were observed between the reason for performing lumbar puncture and the incidence of PDPH. At the time of the LP, 14 of the patients (24.6%) reported having ingested caffeinated beverages in the hours prior to the puncture. A total of 80.7% of the procedures were performed on an outpatient basis at the medical day hospital and 19.3% were performed in the neurology hospital ward. No statistically significant differences were observed regarding the incidence of PDPH and the location of the LP.

In 42 cases (73.7%) a neurology resident physician (MIR) performed the LP, in 6 (10.5%) a neurology specialist, and in 9 patients (15.8%) a resident physician from another medical speciality. The analysis showed no statistically significant differences regarding the incidence of PDPH between the LPs performed by professionals with different degrees of experience.

Regarding the technical aspects of the lumbar puncture: it was performed in a lateral decubitus position in 56 of the patients (98.2%). Patient positioning was considered ideal in 43 of them (75.4%); in 14 patients (24.6%), an adequate position could not be achieved due to physical limitations or poor collaboration. Once the patient was positioned, palpation of the spinous processes was performed immediately in 6 cases (10.4%) with the spinous processes visible. In 34 (57.4) of the patients, palpation of the spinous processes was easily done after taking anatomical references. In 9 patients (15.8%), some difficulty was had to select the anatomical space due to the depth of the spinous processes and/or irregularities in the backbone. Eight patients (14%) presented anatomical features that made it almost impossible to perform adequate palpation.

In 56 of the 57 (98.2%) procedures performed, local anaesthetic was administered first, and the lumbar puncture was performed using a 20 G spinal needle (a 22 G spinal needle used for the remaining procedures).

Immediate access to the subarachnoid space was achieved in 15 cases (26.3%), with reinsertion of the LP needle being necessary at least once in the remaining 42 patients (73.7%). A second attempt was required in 6 patients (22.8%), a third attempt in 4 patients (7%), and four attempts were needed for one patient. During the procedure, a total of 40.4% experienced self-limiting pain irradiating to the lower limbs (LL). There were no statistically significant differences between any of the variables related to the technical aspects of the LP and the appearance of PDPH.

The volume of extracted CSF was measured with an average volume of 4.75 ± 1.46 mL (95 ± 29.3 drops). The macroscopic appearance of the CSF was transparent in 34 cases (59.6%), slightly haematic in 18 (31.6%), and clearly haematic in 5 patients (8.8%). The mean number of red blood cells in CSF extracted was 1097.9 ± 5087.8 red blood cells; the average cell count was 3.6 ± 12.4 cells; mean protein count 52.4 ± 42.6 mg/dl. Mean glucose in CSF was 70.4 ± 16.9 mg/dL while the CSF/serum glucose ratio was 0.67 ± 0.18. Mean pre-puncture capillary blood glucose was 111 ± 33.6 mg/dL. There was no relationship between the macroscopic appearance of the CSF and the appearance of PDPH. Nor were the characteristics of the CSF related in a statistically significant manner to the appearance of PDPH.

Regarding the overall difficulty of the procedure according to the professional performing the LP, this was considered low in 27 cases (47.4%), medium difficulty in 21 procedures (36.8%), and high in 9 procedures (15.8%). Upon dichotomizing the “procedure difficulty” variable into “low difficulty” and “medium-high difficulty”, 14 of the patients (51.9%) from the low difficulty group developed PDPH versus 8 patients (26.7%) from the medium-high difficulty group (p = 0.051) (Table 2).

During the telephone interview held between 7- and 14-days post-LP, 28 patients reported experiencing a headache in the days following the procedure. For 22 of them, the headache was of an orthostatic nature due to low CSF pressure according to the PDPH definition. In the other 6 cases the headache presented non-specific characteristics or the typical headache characteristics normally experienced by the patient. The mean intensity of PDPH pain according to the visual analogue scale was 7.55 ± 1.82 on a scale of 0–10 in which 0 is no headache and 10 maximum intensity headache. For the PDPH intensity analysis, the following two groups were defined: low-moderate intensity headache (score of 6 or lower out of 10) and high intensity headache (score of 7 or higher out of 10). Eight patients presented low-moderate intensity PDPH (36.4%) while the remaining 14 patients presented high intensity PDPH (63.7%). Twelve of the women who presented PDPH (66.7%) experienced a high intensity headache versus 3 men (33.3%), p = 0.137. The 7 patients with medical histories of migraine headaches presented with PDPH (100%) and were classified into the high intensity group versus 4 (50%) of the patients without a history of migraine headache (p = 0.070).

The mean age of the patients with high intensity PDPH was 44.5 ± 16.5 years and 58.3 ± 15 in the PDPH group with an intensity score of 6 or below (p = 0.064). No differences nearing statistical significance were observed in the analysis of the remaining variables regarding the intensity of PDPH.

In 14 of the patients with PDPH (63.6%), the headache was associated with accompanying symptoms: 6 patients experienced dizziness, 6 nausea, 1 patient presented with photophobia, 4 patients reported neck pain or stiffness, 1 patient hearing alteration, and 1 patient reported self-limiting visual alterations. In 9 of the patients with PDPH (40.9%), headache onset began hours after the procedure was performed (within 24 h of the LP). In another 9 patients (40.9%), onset occurred on the second day post LP, and in 4 cases (18.2%) the headache started on day 3 following the lumbar puncture. The mean number of days until headache onset was 1.74 ± 0.73 days. The mean duration of the PDPH was 4.86 ± 2.53 days, with a minimum duration of 1 day and a maximum of 10 days. Four of the patients who presented PDPH (18.2%) required medical care for it, 1 of whom went to the emergency department and the remaining three consulted their primary care doctor.

Of the 22 patients who presented PDPH, 20 (90.1%) required oral analgesics, though none required parenteral treatment. Regarding the number of drugs, 16 (80%) of the patients who used some type of treatment were able to control their pain with one drug. The most commonly used drugs were paracetamol (12 patients) and NSAIDs (9 patients). Other drugs used included metamizole (4 patients), caffeine and codeine (1 patient each). No factors associated with a longer PDPH duration were identified in our patient cohort.

The incidence of PDPH in our patient cohort was 38.6%, just slightly below that found in another recent series, 52.8%,2 with a similar design.

Worthy of note is the variability in the incidence of PDPH in the various series reviewed, which we consider to be related to underdiagnosis given that it often presents with mild symptoms of varying duration. In our series, we found that up to 36.7% of patients developed mild-moderate PDPH (visual analogue scale score of 6 or below), and in none of the cases (even in case of high intensity headache) did patients require parenteral analgesic treatment. In the above-mentioned series,2 female sex and older age were identified as risk factors for PDPH. The results from our patient cohort are in line with that described above, with a higher incidence of PDPH in women, with the results of the analysis showing a trend towards statistical significance.

We found a tendency towards higher incidence of high intensity PDPH in women compared to men, though the results were not statistically significant. We found a similar tendency in younger patients and patients with a clinical history of headache.

A history of migraine-type headaches has been classically identified as a risk factor for the incidence of PDPH17; however, in recent years, studies designed to determine the real incidence and characteristics of PDPH in patients with migraines have not found evidence in favour of a higher incidence of PDPH in this migraine patient group.15 In our patient cohort, 58.3% of the patients who presented PDPH had a history of headache versus 41.7% in the group without PDPH. In this study we placed particular emphasis on identifying migraine features in the patients’ headache history; however, we did not find statistically significant differences in this sense. Nevertheless, when analysing headache intensity, we found greater PDPH intensity in the patient group with headaches associated with migraine characteristics.

Our series displayed greater PDPH intensity in the patient group with a medical history of migraine-style headaches. We observed extensive variability in terms or PDPH duration and intensity in the patient sample analysed.

One of the aspects we aimed to take into account with this study was the analysis of not only PDPH incidence, but also its intensity and duration, particularly due to the potential degree of impairment it can represent in certain instances. Van Oosterhout et al.15 identified the following as predictive factors for longer PDPH duration: sitting position during procedure, history of depression, need for multiple lumbar puncture attempts, and a high level of stress prior to the procedure. Regarding the intensity of the PDPH, we have not found any studies that have had a bearing on this aspect. Based on our findings, we can suggest a possible relationship between female sex, younger age, and a history of migraine headaches with higher intensity PDPH; however, in order to confirm this connection, a study with a larger sample size would need to be performed to provide results with solid evidence.

Following our analysis, professional experience was not related to the onset of PDPH, nor was the presence of cardiovascular risk factors. The vast majority of lumbar punctures were performed with a conventional 20 G needle considering it is the most available and is more convenient from a technical perspective. Nevertheless, a low incidence of PDPH has been reported with the use of conventional 22 G needles, and even lower incidence with atraumatic needle use.11,12 In the cited series,12 there was a 22.4% incidence of PDPH in the conventional needle group versus 8.5% in the atraumatic needle group, in addition to a shorter headache duration for this latter group. However, it must also be pointed out that there was a higher rate of failed attempts in the atraumatic needle group, with 19.5% of the cases requiring reassignment to the conventional needle group. In our setting, the main reason behind continuing to use conventional needles is the limited availability of atraumatic needles, the technical difficulty when using them and, in our opinion, the lack of technical knowledge of neurology staff. Implementing an educational and training program on this technique may be of interest in order to implement their use into regular clinical practice.

This study is prospective in design, with the main determinant for patient inclusion being medical care activity in the neurology department, specifically outpatient activity. At the time of patient recruitment, our primary limitation for the study was a significant period of interruption to in-person medical care due to the SARS-Covid-19 pandemic during the 2020−21 period. Therefore, one of the principal study limitations we can identify is the small sample size analysed. However, despite this limitation in the obtained results, we believe that a wide range of variables were recorded, including LP-related aspects not addressed in other studies.

The incidence of PDPH in our series is 38.6%, though incidence varies greatly among the published series. The principal predisposing factors identified are young age and a medical history of headache. Other factors that we thought a priori could influence the onset of PDPH, such as BMI, biochemical CSF characteristics, or the experience of the professional performing the LP, were not found. Additional studies are needed to evaluate the various factors related to not only incidence, but also the intensity and duration of PDPH, in order to better inform patients and prevent PDPH.

Funding for open access charge: Universidad de Granada / CBUA.

The authors declare that they do not have any conflicts of interest.