Mechanisms behind postspinal headache and brain stem compression following lumbar dural puncture--a physiological approach

Intracranial hypotension with subdural hematoma after spinal anesthesia in obstetric patient: A rare but fatal complication

Intracranial bleed in the form of subdural hematoma (SDH) with intracranial hypotension after spinal anesthesia for cesarean section is a rare condition with an incidence of around 1 in 5,00,000 obstetric populations. As its presentation is similar to post-dural puncture headache (PDPH), it can be misdiagnosed sometimes. Persistent headache for more than 5 days, vomiting, blurring of vision, and convulsion can guide the diagnosis of intracranial bleed. Magnetic resonance imaging (MRI) helps to diagnose the location, size, and other abnormalities of bleed in such patients. The management ranges from conservative to surgical management in the form of craniotomy. Here, we present a case of a 19-year-old woman, who operated on for cesarean section under spinal anesthesia presented with SDH and intracranial hypotension on postoperative day (POD) 6. She was managed conservatively with plenty of intravenous (IV) fluids, bed rest, low head position, analgesics, and antiepileptics. A repeat computed tomography (CT) scan was performed after 14 days, which showed resolved SDH, and the patient was discharged.

An unexpected effect of traumatic and bloody lumbar puncture among patients with primary headaches in emergency department

BACKGROUND

This study aimed to investigate the association between traumatic tap and the incidence of post-dural puncture headache (PDPH) following lumbar puncture (LP) among patients who underwent LP with a primary discharge diagnosis of primary headache in the emergency department (ED).

METHODS

We retrospectively reviewed the medical records of patients who visited a single tertiary ED with the symptom of a headache and underwent LP for cerebrospinal fluid (CSF) analysis between January 2012 and January 2022. Patients who met the definition of PDPH and revisited the ED or outpatient clinic within 2 weeks of discharge were included. For comparative analysis, we divided the groups according to CSF RBC counts (group 1, CSF RBC <10 cells/μL; group 2, 10-100 cells/μL; group 3, ≥100 cells/μL). The primary outcome was the difference in CSF RBC counts between the ED or outpatient clinic revisiting patients who underwent LP within 2 weeks after discharge from the ED. The secondary outcomes were the admission rate and risk factors for PDPH; sex, age, needle size, and CSF pressure.

RESULTS

Data from 112 patients were collected; PDPH was reported in 39 patients (34.8%), and 40 (35.7%) patients were admitted. The median (interquartile range) CSF RBC count was 10 [2-100.8] cells/μL. One-way analysis of variance test of the mean differences among the three groups showed no differences in age, the duration of headache before LP, PLT counts, PT, or aPTT among the groups. There were differences in the number of admitted patients (30 vs. 7 vs. 3, P < 0.001) and the incidence of PDPH (29 vs. 6 vs. 4, P < 0.003). In the comparison of the PDPH and non-PDPH groups, there were differences in age (28.7 ± 8.4 years vs. 36.9 ± 18.4 years, P = 0.01) and the admission rate (85% vs. 9%, P < 0.001).

CONCLUSIONS

Notably, our results suggest that traumatic LP may be an unexpected factor in reducing the occurrence rate of PDPH. Consequently, the admission rate for PDPH was significantly reduced among patients with traumatic LP and those with primary headaches. In this study, we collected and analyzed the data from a relatively small sample size of 112 patients. Further studies are needed to evaluate the relationship between traumatic LP and PDPH.

Effect of Intravenous Ketamine on Hypocranial Pressure Symptoms in Patients with Spinal Anesthetic Cesarean Sections: A Systematic Review and Meta-Analysis

Background: Pregnant women are more likely to suffer post-puncture symptoms such as headaches and nausea due to the outflow of cerebrospinal fluid after spinal anesthesia. Because ketamine has the effect of raising intracranial pressure, it may be able to improve the symptoms of perioperative hypocranial pressure and effectively prevent the occurrence of hypocranial pressure-related side effects. Method: Keywords such as ketamine, cesarean section, and spinal anesthesia were searched in databases including Medline, Embase, Web of Science, and Cochrane from 1976 to 2021. Thirteen randomized controlled trials were selected for the meta-analysis. Results: A total of 12 randomized trials involving 2099 participants fulfilled the inclusion criteria. There was no significant association between ketamine and the risk of headaches compared to the placebo (RR = 1.12; 95% CI: 0.53, 2.35; p = 0.77; I² = 62%). There was no significant association between ketamine and nausea compared to the placebo (RR = 0.66; 95% CI: 0.40, 1.09; p = 0.10; I² = 57%). No significant associations between ketamine or the placebo and vomiting were found (RR = 0.94; 95% CI: 0.53, 1.67; p = 0.83; I² = 72%). Conclusion: Intravenous ketamine does not improve the symptoms caused by low intracranial pressure after spinal anesthesia in patients undergoing cesarean section.

Magnetic resonance imaging of cerebrospinal fluid spread in the epidural space and postdural puncture headache in obstetrics: A proof-of-concept study

BACKGROUND

Currently, performing an epidural blood patch (EBP) for postdural puncture headache (PDPH) remains a subjective clinical decision. An evidence-based protocol may be of value in identifying women at high risk of developing a severe PDPH.

OBJECTIVE

To investigate a potential correlation between the extent of CSF spread in the epidural space, as noted on Magnetic Resonance Imaging (MRI), and the likelihood of development of severe PDPH in obstetric patients.

DESIGN

A prospective double-blind quasi-observational study.

SETTING

Eight tertiary obstetric units, from NHS hospitals.

PATIENTS

Parturients with accidental dural puncture (ADP) underwent T1 and T2-weighted MRI scans of the brain and lumbar spine within 48 h after delivery. All women were followed up, daily, for 1 week.

MAIN OUTCOME MEASURES

For each woman, a PDPH severity score was calculated using a four-point Verbal Reporting Scale (none = 0, mild = 1, moderate = 2, severe = 3), with additional points awarded for visual, auditory and emetic symptoms. MRIs were reported by a neuroradiologist, blind to the patient details, using a predefined MRI score.

RESULTS

Twenty-two parturients were recruited; 86% (n=19) developed PDPH and 10 of these (53%) required an EBP. The median (range) time for the onset of PDPH was 24 (4 to 126) hours. The median (range) cumulative PDPH severity score was 10 (0 to 21), whereas, the median (range) MRI score was 2.5 (0 to 12). Spearman (rs) analysis identified a significant positive correlation (rs = 0.46; P = 0.024) between cumulative PDPH severity and MRI scores. Of all the radiological features identified in an MRI (lumbar dural shift, caudal brain displacement, epidural or intrathecal blood), the presence of intrathecal blood was most strongly correlated with PDPH severity (P = 0.043).

CONCLUSION

Following an ADP, the extent of CSF spread in the epidural space correlates with the severity of subsequent PDPH.

CLINICAL TRIAL NUMBER AND REGISTRY URL

ISRCTN14959004, https://www.isrctn.com/.

Incidence of postural headache after lumbar puncture requiring epidural blood patch: Effects of needle caliber; 2-year experience

PURPOSE

A common complication of lumbar puncture (LP) is postural headaches. Epidural blood patches are recommended if patients fail conservative management. Owing to a perceived increase in the number of post-lumbar puncture headaches (PLPHs) requiring epidural blood patches at a regional hospital in our network, the decision was made to switch from 20 to 22 gauge needles for routine diagnostic LPs.

MATERIALS AND METHODS

Patients presenting for LP and myelography at one network regional hospital were included in the study. The patients were contacted by nursing staff 3 days post-procedure; those patients who still had postural headaches after conservative management and received epidural blood patches were considered positive cases. In total, 292 patients were included; 134 underwent LP with 20-gauge needles (53 male, 81 female, average age 57.7) and 158 underwent LP with 22-gauge needles (79 male, 79 female, average age 54.6).

RESULTS

Of 134 patients undergoing LP with 20-gauge needles, 15 (11%) had PLPH requiring epidural blood patch (11 female, 3 male, average age 38). Of 158 patients undergoing LP with 22-gauge needles, only 5 (3%) required epidural blood patches (all female, average age 43). The difference was statistically significant (p < 0.01). Risk factors for PLPH included female gender, younger age, lower body mass index, history of prior PLPH and history of headaches.

CONCLUSION

Switching from 20-gauge to 22-gauge needles significantly decreased the incidence of PLPH requiring epidural blood patch. Narrower gauge or non-cutting needles should be considered in patients with risk factors for PLPH, allowing for CSF requirements.

Needle gauge and tip designs for preventing post-dural puncture headache (PDPH)

BACKGROUND

Post-dural puncture headache (PDPH) is one of the most common complications of diagnostic and therapeutic lumbar punctures. PDPH is defined as any headache occurring after a lumbar puncture that worsens within 15 minutes of sitting or standing and is relieved within 15 minutes of the patient lying down. Researchers have suggested many types of interventions to help prevent PDPH. It has been suggested that aspects such as needle tip and gauge can be modified to decrease the incidence of PDPH.

OBJECTIVES

To assess the effects of needle tip design (traumatic versus atraumatic) and diameter (gauge) on the prevention of PDPH in participants who have undergone dural puncture for diagnostic or therapeutic causes.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL and LILACS, as well as trial registries via the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal in September 2016. We adopted the MEDLINE strategy for searching the other databases. The search terms we used were a combination of thesaurus-based and free-text terms for both interventions (lumbar puncture in neurological, anaesthesia or myelography settings) and headache.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) conducted in any clinical/research setting where dural puncture had been used in participants of all ages and both genders, which compared different tip designs or diameters for prevention of PDPH DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 70 studies in the review; 66 studies with 17,067 participants were included in the quantitative analysis. An additional 18 studies are awaiting classification and 12 are ongoing. Fifteen of the 18 studies awaiting classification mainly correspond to congress summaries published before 2010, in which the available information does not allow the complete evaluation of all their risks of bias and characteristics. Our main outcome was prevention of PDPH, but we also assessed the onset of severe PDPH, headache in general and adverse events. The quality of evidence was moderate for most of the outcomes mainly due to risk of bias issues. For the analysis, we undertook three main comparisons: 1) traumatic needles versus atraumatic needles; 2) larger gauge traumatic needles versus smaller gauge traumatic needles; and 3) larger gauge atraumatic needles versus smaller gauge atraumatic needles. For each main comparison, if data were available, we performed a subgroup analysis evaluating lumbar puncture indication, age and posture.For the first comparison, the use of traumatic needles showed a higher risk of onset of PDPH compared to atraumatic needles (36 studies, 9378 participants, risk ratio (RR) 2.14, 95% confidence interval (CI) 1.72 to 2.67, I² = 9%).In the second comparison of traumatic needles, studies comparing various sizes of large and small gauges showed no significant difference in effects in terms of risk of PDPH, with the exception of one study comparing 26 and 27 gauge needles (one study, 658 participants, RR 6.47, 95% CI 2.55 to 16.43).In the third comparison of atraumatic needles, studies comparing various sizes of large and small gauges showed no significant difference in effects in terms of risk of PDPH.We observed no significant difference in the risk of paraesthesia, backache, severe PDPH and any headache between traumatic and atraumatic needles. Sensitivity analyses of PDPH results between traumatic and atraumatic needles omitting high risk of bias studies showed similar results regarding the benefit of atraumatic needles in the prevention of PDPH (three studies, RR 2.78, 95% CI 1.26 to 6.15; I² = 51%).

AUTHORS' CONCLUSIONS

There is moderate-quality evidence that atraumatic needles reduce the risk of post-dural puncture headache (PDPH) without increasing adverse events such as paraesthesia or backache. The studies did not report very clearly on aspects related to randomization, such as random sequence generation and allocation concealment, making it difficult to interpret the risk of bias in the included studies. The moderate quality of the evidence for traumatic versus atraumatic needles suggests that further research is likely to have an important impact on our confidence in the estimate of effect.

Posture and fluids for preventing post-dural puncture headache

BACKGROUND

Post-dural puncture headache (PDPH) is a common complication of lumbar punctures. Several theories have identified the leakage of cerebrospinal fluid (CSF) through the hole in the dura as a cause of this side effect. It is therefore necessary to take preventive measures to avoid this complication. Prolonged bed rest has been used to treat PDPH once it has started, but it is unknown whether prolonged bed rest can also be used to prevent it. Similarly, the value of administering fluids additional to those of normal dietary intake to restore the loss of CSF produced by the puncture is unknown. This review is an update of a previously published review in the Cochrane Database of Systematic Reviews (Issue 7, 2013) on "Posture and fluids for preventing post-dural puncture headache".

OBJECTIVES

To assess whether prolonged bed rest combined with different body and head positions, as well as administration of supplementary fluids after lumbar puncture, prevent the onset of PDPH in people undergoing lumbar puncture for diagnostic or therapeutic purposes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and LILACS, as well as trial registries up to February 2015.

SELECTION CRITERIA

We identified randomized controlled trials that compared the effects of bed rest versus immediate mobilization, head-down tilt versus horizontal position, prone versus supine positions during bed rest, and administration of supplementary fluids versus no/less supplementation, as prevention measures for PDPH in people who have undergone lumbar puncture.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for eligibility through the web-based software EROS (Early Review Organizing Software). Two different review authors independently assessed risk of bias using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We resolved any disagreements by consensus. We extracted data on cases of PDPH, severe PDPH, and any headache after lumbar puncture and performed intention-to-treat analyses and sensitivity analyses by risk of bias. We assessed the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation) and created a 'Summary of findings' table.

MAIN RESULTS

We included 24 trials with 2996 participants in this updated review. The number of participants in each trial varied from 39 to 382. Most of the included studies compared bed rest versus immediate mobilization, and only two assessed the effects of supplementary fluids versus no supplementation. We judged the overall risk of bias of the included studies as low to unclear. The overall quality of evidence was low to moderate, downgraded because of the risk of bias assessment in most cases. The primary outcome in our review was the presence of PDPH.There was low quality evidence for an absence of benefits associated with bed rest compared with immediate mobilization on the incidence of severe PDPH (risk ratio (RR) 0.98; 95% confidence interval (CI) 0.68 to 1.41; participants = 1568; studies = 9) and moderate quality evidence on the incidence of any headache after lumbar puncture (RR 1.16; 95% CI 1.02 to 1.32; participants = 2477; studies = 18). Furthermore, bed rest probably increased PDPH (RR 1.24; 95% CI 1.04 to 1.48; participants = 1519; studies = 12) compared with immediate mobilization. An analysis restricted to the most methodologically rigorous trials (i.e. those with low risk of bias in allocation method, missing data and blinding of outcome assessment) gave similar results. There was low quality evidence for an absence of benefits associated with fluid supplementation on the incidence of severe PDPH (RR 0.67; 95% CI 0.26 to 1.73; participants = 100; studies = 1) and PDPH (RR 1; 95% CI 0.59 to 1.69; participants = 100; studies = 1), and moderate quality evidence on the incidence of any headache after lumbar puncture (RR 0.94; 95% CI 0.66 to 1.34; participants = 200; studies = 2). We did not expect other adverse events and did not assess them in this review.

AUTHORS' CONCLUSIONS

Since the previous version of this review, we found one new study for inclusion, but the conclusion remains unchanged. We considered the quality of the evidence for most of the outcomes assessed in this review to be low to moderate. As identified studies had shortcomings on aspects related to randomization and blinding of outcome assessment, we therefore downgraded the quality of the evidence. In general, there was no evidence suggesting that routine bed rest after dural puncture is beneficial for the prevention of PDPH onset. The role of fluid supplementation in the prevention of PDPH remains unclear.

Drug therapy for treating post-dural puncture headache

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 8, 2011, on 'Drug therapy for treating post-dural puncture headache'.Post-dural puncture headache (PDPH) is the most common complication of lumbar puncture, an invasive procedure frequently performed in the emergency room. Numerous pharmaceutical drugs have been proposed to treat PDPH but there are still some uncertainties about their clinical effectiveness.

OBJECTIVES

To assess the effectiveness and safety of drugs for treating PDPH in adults and children.

SEARCH METHODS

The searches included the Cochrane Central Register of Controlled Trials (CENTRAL 2014, Issue 6), MEDLINE and MEDLINE in Process (from 1950 to 29 July 2014), EMBASE (from 1980 to 29 July 2014) and CINAHL (from 1982 to July 2014). There were no language restrictions.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) assessing the effectiveness of any pharmacological drug used for treating PDPH. Outcome measures considered for this review were: PDPH persistence of any severity at follow-up (primary outcome), daily activity limited by headache, conservative supplementary therapeutic option offered, epidural blood patch performed, change in pain severity scores, improvements in pain severity scores, number of days participants stay in hospital, any possible adverse events and missing data.

DATA COLLECTION AND ANALYSIS

Review authors independently selected studies, assessed risk of bias and extracted data. We estimated risk ratios (RR) for dichotomous data and mean differences (MD) for continuous outcomes. We calculated a 95% confidence interval (CI) for each RR and MD. We did not undertake meta-analysis because the included studies assessed different sorts of drugs or different outcomes. We performed an intention-to-treat (ITT) analysis.

MAIN RESULTS

We included 13 small RCTs (479 participants) in this review (at least 274 participants were women, with 118 parturients after a lumbar puncture for regional anaesthesia). In the original version of this Cochrane review, only seven small RCTs (200 participants) were included. Pharmacological drugs assessed were oral and intravenous caffeine, subcutaneous sumatriptan, oral gabapentin, oral pregabalin, oral theophylline, intravenous hydrocortisone, intravenous cosyntropin and intramuscular adrenocorticotropic hormone (ACTH).Two RCTs reported data for PDPH persistence of any severity at follow-up (primary outcome). Caffeine reduced the number of participants with PDPH at one to two hours when compared to placebo. Treatment with caffeine also decreased the need for a conservative supplementary therapeutic option.Treatment with gabapentin resulted in better visual analogue scale (VAS) scores after one, two, three and four days when compared with placebo and also when compared with ergotamine plus caffeine at two, three and four days. Treatment with hydrocortisone plus conventional treatment showed better VAS scores at six, 24 and 48 hours when compared with conventional treatment alone and also when compared with placebo. Treatment with theophylline showed better VAS scores compared with acetaminophen at two, six and 12 hours and also compared with conservative treatment at eight, 16 and 24 hours. Theophylline also showed a lower mean "sum of pain" when compared with placebo. Sumatriptan and ACTH did not show any relevant effect for this outcome.Theophylline resulted in a higher proportion of participants reporting an improvement in pain scores when compared with conservative treatment.There were no clinically significant drug adverse events.The rest of the outcomes were not reported by the included RCTs or did not show any relevant effect.

AUTHORS' CONCLUSIONS

None of the new included studies have provided additional information to change the conclusions of the last published version of the original Cochrane review. Caffeine has shown effectiveness for treating PDPH, decreasing the proportion of participants with PDPH persistence and those requiring supplementary interventions, when compared with placebo. Gabapentin, hydrocortisone and theophylline have been shown to decrease pain severity scores. Theophylline has also been shown to increase the proportion of participants that report an improvement in pain scores when compared with conventional treatment.There is a lack of conclusive evidence for the other drugs assessed (sumatriptan, adrenocorticotropic hormone, pregabalin and cosyntropin).These conclusions should be interpreted with caution, due to the lack of information to allow correct appraisal of risk of bias, the small sample sizes of the studies and also their limited generalisability, as nearly half of the participants were postpartum women in their 30s.

Posture and fluids for preventing post-dural puncture headache

BACKGROUND

Post-dural puncture headache (PDPH) is a common complication of lumbar punctures. Several theories have identified the leakage of cerebrospinal fluid (CSF) through the hole in the dura as a cause of this side effect. Therefore, it is necessary to take preventive measures to avoid this complication. Prolonged bed rest has been used as a therapeutic measure once PDPH has started, but it is unknown if it can be also be used to prevent it. Similarly, the value of administering fluids additional to those of normal dietary intake to restore the loss of CSF produced by the puncture is unknown.

OBJECTIVES

To assess whether prolonged bed rest combined with different body and head positions, as well as administration of supplementary fluids after lumbar puncture, prevent the onset of PDPH in people undergoing lumbar puncture for diagnostic or therapeutic purposes.

SEARCH METHODS

We searched the Cochrane Controlled Trials Register, MEDLINE, EMBASE, and LILACS up to June 2013.

SELECTION CRITERIA

We identified randomized controlled trials (RCTs) that compared the effects of bed rest versus early/immediate mobilization, head-down tilt versus horizontal position, prone versus supine positions during bed rest, and administration of supplementary fluids versus no/less supplementation, as prevention measures for PDPH in people who have undergone lumbar puncture.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for eligibility through the web-based software EROS (Early Review Organizing Software). Two different review authors independently assessed risk of bias using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We solved any disagreements by consensus. We extracted data on cases of PDPH, severe PDPH, and any headache after lumbar puncture and performed intention-to-treat analyses and sensitivity analyses by risk of bias.

MAIN RESULTS

We included 23 trials (2477 participants) in this review. There was no beneficial effect associated with bed rest compared with immediate mobilization on the incidence of PDPH (risk for bed rest 26.4%; risk for mobilization 20.5%; risk ratio (RR) 1.30; 95% confidence interval (CI) 1.09 to 1.55), severe PDPH (risk for bed rest 10.6%; risk for mobilization 10.7%; RR 1.00; 95% CI 0.75 to 1.32), and presence of any headache after lumbar puncture (risk for bed rest 33.6%; risk for mobilization 28.6%; RR 1.18; 95% CI 1.05 to 1.32). Analyses restricted to the most methodologically rigorous trials gave similar results. Likewise, the two trials that assessed fluid supplementation did not find this preventive measure to be useful in the prevention of PDPH.

AUTHORS' CONCLUSIONS

There is no evidence from RCTs that suggests that routine bed rest after dural puncture is beneficial for the prevention of PDPH onset. The role of fluid supplementation in the prevention of PDPH remains unclear.

Drug therapy for preventing post-dural puncture headache

BACKGROUND

Post-dural (post-lumbar or post-spinal) puncture headache (PDPH) is one of the most common complications of diagnostic, therapeutic or inadvertent lumbar punctures. Many drug options have been used to prevent headache in clinical practice and have also been tested in some clinical studies, but there are still some uncertainties about their clinical effectiveness.

OBJECTIVES

To assess the effectiveness and safety of drugs for preventing PDPH in adults and children.

SEARCH METHODS

The search strategy included the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library 2012, Issue 5), MEDLINE (from 1950 to May 2012), EMBASE (from 1980 to May 2012) and CINAHL (from 1982 to June 2012). There was no language restriction.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) that assessed the effectiveness of any drug used for preventing PDPH.

DATA COLLECTION AND ANALYSIS

Review authors independently selected studies, assessed risks of bias and extracted data. We estimated risk ratios (RR) for dichotomous data and mean differences (MD) for continuous outcomes. We calculated a 95% confidence interval (CI) for each RR and MD. We did not undertake meta-analysis because participants' characteristics or assessed doses of drugs were too different in the included studies. We performed an intention-to-treat (ITT) analysis.

MAIN RESULTS

We included 10 RCTs (1611 participants) in this review with a majority of women (72%), mostly parturients (women in labour) (913), after a lumbar puncture for regional anaesthesia. Drugs assessed were epidural and spinal morphine, spinal fentanyl, oral caffeine, rectal indomethacin, intravenous cosyntropin, intravenous aminophylline and intravenous dexamethasone.All the included RCTs reported data on the primary outcome, i.e. the number of participants affected by PDPH of any severity after a lumbar puncture. Epidural morphine and intravenous cosyntropin reduced the number of participants affected by PDPH of any severity after a lumbar puncture when compared to placebo. Also, intravenous aminophylline reduced the number of participants affected by PDPH of any severity after a lumbar puncture when compared to no intervention, while intravenous dexamethasone increased it. Spinal morphine increased the number of participants affected by pruritus when compared to placebo, and epidural morphine increased the number of participants affected by nausea and vomiting when compared to placebo. Oral caffeine increased the number of participants affected by insomnia when compared to placebo.The remainder of the interventions analysed did not show any relevant effect for any of the outcomes.None of the included RCTs reported the number of days that patients stayed in hospital.

AUTHORS' CONCLUSIONS

Morphine and cosyntropin have shown effectiveness for reducing the number of participants affected by PDPH of any severity after a lumbar puncture, when compared to placebo, especially in patients with high risk of PDPH, such as obstetric patients who have had an inadvertent dural puncture. Aminophylline also reduced the number of participants affected by PDPH of any severity after a lumbar puncture when compared to no intervention in patients undergoing elective caesarean section. Dexamethasone increased the risk of PDPH, after spinal anaesthesia for caesarean section, when compared to placebo. Morphine also increased the number of participants affected by adverse events (pruritus and nausea and vomiting)There is a lack of conclusive evidence for the other drugs assessed (fentanyl, caffeine, indomethacin and dexamethasone).These conclusions should be interpreted with caution, owing to the lack of information, to allow correct appraisal of risk of bias and the small sample sizes of studies.

Drug therapy for treating post-dural puncture headache

BACKGROUND

Post-dural puncture headache (PDPH) is the most common complication of lumbar puncture, an invasive procedure frequently performed in the emergency room. Numerous pharmaceutical drugs have been proposed to treat PDPH but there are still some uncertainties about their clinical effectiveness.

OBJECTIVES

To assess the effectiveness and safety of drugs for treating PDPH in adults and children.

SEARCH STRATEGY

The search strategy included the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2011, Issue 2), MEDLINE (from 1950 to June 2011), EMBASE (from 1980 to June 2011) and CINAHL (from 1982 to June 2011). There was no language restriction.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) assessing the effectiveness of any pharmacological drug used for treating PDPH.

DATA COLLECTION AND ANALYSIS

Review authors independently selected studies, assessed risks of bias and extracted data. We estimated risk ratios (RR) for dichotomous data and mean differences (MD) for continuous outcomes. We calculated a 95% confidence interval (CI) for each RR and MD. We did not undertake meta-analysis because the included studies assessed different sorts of drugs or different outcomes. We performed an intention-to-treat (ITT) analysis.

MAIN RESULTS

We included seven RCTs (200 participants) in this review (between 88% and 90.5% were women; mostly parturients (84% to 87%) after a lumbar puncture for a regional anaesthesia). Pharmacological drugs assessed were oral and intravenous caffeine, subcutaneous sumatriptan, oral gabapentin, oral theophylline, intravenous hydrocortisone and intramuscular adrenocorticotropic hormone (ACTH).One RCT reported data about PDPH persistence of any severity at follow up (primary outcome); caffeine reduced the number of participants with PDPH at one to two hours when compared to placebo. Treatment with caffeine also decreased the need for a conservative supplementary therapeutic option. Treatment with gabapentin versus placebo reported better visual analogue scale (VAS) scores after one, two, three and four days; treatment with hydrocortisone plus conventional treatment showed better VAS scores than conventional treatment alone at six, 24 and 48 hours and treatment with theophylline showed a lower mean "sum of pain" when compared with placebo. Sumatriptan and ACTH did not show any relevant effect for this outcome.There were no clinically significant drug adverse events.The rest of the outcomes were not reported by the RCTs or did not show any relevant effect.

AUTHORS' CONCLUSIONS

Caffeine has shown effectiveness for treating PDPH, decreasing the proportion of participants with PDPH persistence and those requiring supplementary interventions, when compared with placebo. Gabapentin, theophylline and hydrocortisone have also shown a decrease in pain severity scores when compared with placebo or conventional care.There is a lack of conclusive evidence for the other drugs assessed (sumatriptan and ACTH).These conclusions should be interpreted with caution, due to the lack of information to allow correct appraisal of risk of bias, the small sample sizes of studies and also the limited generalisability, as most participants were post-partum women in their 30s.

Coma after spinal anaesthesia in a patient with an unknown intracerebral tumour

Spinal anaesthesia is contraindicated in patients with elevated intracranial pressure or space-occupying intracranial lesions. Drainage of the lumbar cerebrospinal fluid (CSF) can increase the pressure gradient between the spinal, supratentorial and infratentorial compartments. This can result in rapid herniation of the brain stem or occluding hydrocephalus. We present a case of a female patient with an occult brain tumour who received a spinal anaesthesia for an orthopaedic procedure. The primary course of anaesthesia was uneventful. Several hours after surgery, the patient became increasingly disoriented and agitated. The next day, she was found comatose. A computed tomogram of the head revealed herniation of the brain stem, resulting in an occluding hydrocephalus due to a prior not known infratentorial mass. By acute relieving of the intracranial pressure by external CSF drainage, the mass was removed 2 days later. The further post-operative course was uneventful and the patient was discharged from the hospital without neurological deficit 3 weeks after the primary surgery.

Jugular venous pooling during lowering of the head affects blood pressure of the anesthetized giraffe

How blood flow and pressure to the giraffe's brain are regulated when drinking remains debated. We measured simultaneous blood flow, pressure, and cross-sectional area in the carotid artery and jugular vein of five anesthetized and spontaneously breathing giraffes. The giraffes were suspended in the upright position so that we could lower the head. In the upright position, mean arterial pressure (MAP) was 193 ± 11 mmHg (mean ± SE), carotid flow was 0.7 ± 0.2 l/min, and carotid cross-sectional area was 0.85 ± 0.04 cm2. Central venous pressure (CVP) was 4 ± 2 mmHg, jugular flow was 0.7 ± 0.2 l/min, and jugular cross-sectional area was 0.14 ± 0.04 cm2 ( n = 4). Carotid arterial and jugular venous pressures at head level were 118 ± 9 and −7 ± 4 mmHg, respectively. When the head was lowered, MAP decreased to 131 ± 13 mmHg, while carotid cross-sectional area and flow remained unchanged. Cardiac output was reduced by 30%, CVP decreased to −1 ± 2 mmHg ( P < 0.01), and jugular flow ceased as the jugular cross-sectional area increased to 3.2 ± 0.6 cm2 ( P < 0.01), corresponding to accumulation of ∼1.2 l of blood in the veins. When the head was raised, the jugular veins collapsed and blood was returned to the central circulation, and CVP and cardiac output were restored. The results demonstrate that in the upright-positioned, anesthetized giraffe cerebral blood flow is governed by arterial pressure without support of a siphon mechanism and that when the head is lowered, blood accumulates in the vein, affecting MAP.

Postoperative nausea and vomiting and pain after transsphenoidal surgery: a review of 877 patients

Although postoperative nausea and vomiting and pain after supra- and infratentorial craniotomy have been evaluated in multiple studies, there are few data regarding pain or postoperative nausea and vomiting after transsphenoidal procedures. Therefore, we reviewed the perioperative records of 877 patients undergoing transsphenoidal surgery by the same surgeon. The overall incidence of postoperative emesis was 7.5%, significantly less than most studies of neurosurgical patients. An intraoperative cerebrospinal fluid leak and subsequent fat grafting, the use of lumbar intrathecal catheter, and patients presenting for the resection of a craniopharyngiomas all had a significantly increased incidence of postoperative emesis (11.4%, 17.1%, and 18%, respectively). Interestingly, antiemetic prophylaxis did not decrease the risk of vomiting overall or in any cohort of patients; however, both droperidol and ondansetron decreased the incidence of nausea in the postanesthesia care unit (PACU). Regarding pain and morphine consumption, patients who later developed diabetes insipidus had a significant increase in morphine requirements in the PACU. No other disease state was associated with increased pain or morphine consumption in the PACU.

Multimodal cerebral monitoring and decompressive surgery for the treatment of severe bacterial meningitis with increased intracranial pressure

Bacterial meningitis is still associated with a high mortality, mainly because of cerebral herniation as a result of increased intracranial pressure. Published data stress the necessity of an early diagnosis and immediate start of antibiotic therapy. Nevertheless, there are only few reports in which therapeutic strategy was based on the monitoring and the reduction of intracranial pressure (ICP). We report one case of bacterial meningitis caused by Neisseria meningitidis with an initial ICP value of 60 mmHg, which was treated by large hemicraniectomy and ventriculostomy, leading to a favorable neurological long-term result. The surgical decision was accelerated by an accurate ICP evaluation based on cerebral monitoring [transcranial Doppler ultrasonography (TCD) and intracranial ICP-device]. In selected patients with bacterial meningitis and clinical and radiological evidence of elevated ICP, cerebral monitoring and aggressive reduction of ICP may be crucial to improve survival and neurological outcome. When maximal medical ICP treatment fails to reduce severe intracranial hypertension, decompressive craniectomy should be rapidly proposed.

Effects on intracranial pressure of dural puncture in supine and head-elevated positions. A study on the cat

BACKGROUND

Lumbar dural puncture may reduce intracranial pressure (ICP) due to a hydrostatic pressure gradient created by distal opening of the spinal fluid column towards the atmosphere. The magnitude of the reduction in hydrostatic force on the brain should depend on the vertical distance between the brain and the dural opening, and thus will increase by head elevation. No studies have analyzed ICP after dural puncture in supine and upright positions.

METHODS

This study on the cat records ICP, mean arterial pressure, and central venous pressure before and after dural puncture in supine and head-elevated positions. The dural puncture was performed at a level corresponding to the lumbar region.

RESULTS

Initially ICP was 10.9 +/- 1.9 mmHg (mean +/- SD), which decreased to 5.1 +/- 2.0 mmHg after 24.5 cm (18 mmHg) of head elevation (n = 7). Intracranial pressure decreased to 5.2 +/-3.5 mmHg following dural puncture in the supine position and to -11.3 +/- 4.2 mmHg after the head elevation (n = 7). Active drainage of CSF fluid in the supine position in a volume similar to that spontaneously drained after head elevation reduced ICP by 2.0 +/- 0.5 mmHg (n = 3).

CONCLUSIONS

The results show that a significant ICP reduction may occur following opening of the spinal canal. The reduction can be explained more by hydrostatic forces than by loss of CSF; also explaining why it is more significant when upright than supine. The decrease in ICP increases transvascular pressure, which may induce the disappearance of the normally present subdural venous collapse with an increase in venous blood volume.