By Mohd Fadzli Bin Zahari Supervised By Dr Abdul Karim

References  Nath G, Subrahmanyam M. Headache in the parturient: Pathophysiology and management of post-dural puncture headache. J Obstet Anaesth Crit Care 2011;1:57-66.

Outline  Introduction / overview  Incidence of postpartum headache  Post dural puncture headache (PDPH)  PDPH with different neuraxial techniques in obstetric patients  Pathophysiology  Presentation  Prevention  Management / treatment

Introduction / Overview  Childbirth is a life-changing experience with profound physical, social as well as psychological effects on the mother  Headache is one of the most common complaints. Incidence ranging from 11 to 80% of parturients  Primary headache: i.e migraine, tension and cluster headaches precipitated by multifactors  Secondary headache: i.e. PDPH (broadly use of regional anesthesia in delivery & labour anelgesia)  Pregnancy associated condition: i.e. preeclampsia, cerebral venous thrombosis

Incidence of postpartum headache  A prospective study looking at 985 parturients found that 381 patients (39%) complained of headache  tension-type/migraine comprised the most common cause (47%)  Preeclampsia / eclampsia (24%)  PDPH (16%)

Post dural puncture headache (PDPH)  By International Headache Society: Headache that worsens within 15 min after sitting or standing and improves within 15 min after lying with at least one of the following - neck stiffness, tinnitus, hypacusia, photophobia or nausea with history of within 5 days after dura puncture.

 PDPH associated with neuraxial techniques  Factors affecting incidence of PDPH are:  Needle size  Needle tips Incidence with needle (size & tips) usage in neuraxial technique Reduction from 66% to 33-36% incidence using 22G from 17 / 18 G Quincke needles Reduction down to % using smaller Quincke needles of 24G to 32G design of needle tips from cutting Quincke needles to pencil-point reduced incidence to 0-10% head-to-head comparison of Quincke and pencil-point needles of the same size (27 G, 0.40 mm O.D.) – incidence 8.1 and 1.9%;

 Smaller needle (< 27G) however associated greater technical difficulties, which in turn may lead to multiple attempts, leading to a higher incidence of PDPH  Other risk factors for PDPH:  female sex  younger age group  obstetric population

PDPH With Different Neuraxial Techniques In Obstetric Patients

Spinal Anesthesia  The main factor determining the frequency of PDPH following spinal anesthesia is the size and design of the needle  National Obstetric Anaesthetic Database (NOAD) which included 65,348 women who had anesthetic interventions in the UK during the year 1999 reported a PDPH incidence of 1.9% after spinal anesthesia  more recent reports from developing countries found higher incidences of PDPH (4.7, 8.3 and 23%) mainly due to the use of Quinke needles

Epidural Anesthesia  incidence of PDPH after epidural has ranged from 0.5 to 4.2% in different study  The primary cause is accidental dural puncture (ADP) which may be recognized during the procedure  nearly 40% of inadvertent dural punctures are only recognized by the onset of PDPH  PDPH incidence ranges from 52% to 88% following dural puncture with tuohy needle

Combined Spinal-epidural  The incidence of ADP and PDPH with combined spinal-epidural technique would be expected to be similar or greater compared to epidural technique alone  Technical problem with the needle-through needle technique:  difficulty in obtaining CSF which may necessitate multiple dural punctures with the spinal needle  difficulty in immobilizing the spinal needle in the epidural needle  difficulty in threading the epidural catheter after the intrathecal injection  Intravascular puncture with the epidural catheter

 Double - space CSE technique is used to overcome needle-through needle technique flaw but increase rate of incidence for PDPH is double due to epidural puncture is done twice.

StudyRemarks Early pilot survey of 300 women given CSE for labor analgesia ADP occurred in 3 patients while 7 developed PDPH (2.3%) 1565 women receiving CSE for labor analgesia (same unit as above) ADP rate decreased to 0.45% and PDPH to 0.58% Large retrospective analysis of 6497 cases comparing epidural and CSE (needle- through-needle) techniques for labor analgesia PDPH occurred in 0.8 and 1.4% of the epidural and CSE groups respectively retrospective analysis of 3519 elective cesarean sections using the double-space CSE technique ADP rate of 0.7% (1:141) with a 52% incidence of severe PDPH

Pathophysiology

 Spinal duramater extends from the foramen magnum to the second sacral vertebra  It composed of layers of collagen and elastic fibers - recent electron and light microscopic studies show that though the outer dural fibers are longitudinally oriented but this arrangement is not repeated in all the layers  posterior dural thickness is variable between individuals and in different areas in the same individual

 About 500 ml of CSF is produced per day (21 ml/h); and at any time, and the volume of CSF ranges from 125 to 150 ml half of which is intracranial  The lumbar CSF pressure is 5–15 cmH2O but increases to 40 cmH2O in the upright position  PDPH is thought to be caused by CSF leakage through the dural puncture at a greater rate than its production leading to a fall in CSF pressure leading to causes of headache by 2 mechanisms

 Mechanisms  sagging of the intracranial structures in the uprightposition; with traction on the meninges, cranial nerves and upper cervical nerves causing frontal, occipital and cervical pain  compensatory vasodilatation in response to the low intracranial pressure  The upright position worsens the headache:  decreasing the intracranial pressure  increasing the rate of loss of CSF

Presentation  Majority of PDPH present within h of the procedure. Meta analysis showed the onset 1-7 days after the puncture  Cranial nerve palsies:  Abduscens (92–95%) causing diplopia  Oculomotor and trochlear nerve  Trigeminal and facial nerve  Auditory nerve  Ophtalmic

 Untreated PDPH can lead to intracranial complication  SDH  Cerebral venous thrombosis  reversible cerebral vasoconstrictive syndromes  Present as sudden onset severe headache  May associate with neuro deficit & seizure  Self limiting  In one series of 67 patients  SAH in 22%  ICH in 6%  Seizure in 3%  posterior leukoencephalopathy in 9%

Prevention  Using the smallest gauge needles practicable is the first step in preventing PDPH  25G or 27G for spinal  Tuohy 18G & smaller for epidural  Use pencil tip needle  Ultrasound guidance  In a study of 300 patients, pre-procedure ultrasound caused a significant reduction in puncture attempts and side effects and better quality of analgesia  Another study by the same group found that success rate in the first 60 attempts at obstetric epidural insertion by a group of residents was significantly higher

 Orientating the bevel of the needle to be parallel to the fibers  Using saline rather than air for epidural insertion  After ADP, some studies advocated the administration of a prophylactic blood patch through the epidural catheter before its removal but randomize control trial did not show a reduction in PDPH incidence though a prophylactic EBP did reduce the duration and severity of the headache

 Epidural saline infusion is another intervention which was advocated in the 70s at rates of 1 to 1.5 L/day to increase the epidural pressure in order to reduce the CSF leak

 A bolus of saline has also been advocated to raise the epidural pressure, but this carries the danger of an excessively high block or a total spinal

Treatment

Conservative  Maintenance of hydration  Prescription of simple analgesics  Patients may prefer to lie down in the position of their choice  abdominal binder raises the intraabdominal and CSF pressure and may provide some relief

Pharmacology  Caffeine  A CNS stimulant which also has a cerebral vasoconstrictive effect  shown to relieve mild PDPH but the effect is transient  A structured evidence-based clinical neurologic practice review by three academic institutions found no valid pharmacological rationale for caffeine as an antinociceptive agent for PDPH  occasionally is associated with post-partum seizures

 Sumatriptan  5-HT agonist with cerebral vasoconstrictive effects  Controlled trial recruiting parturients with severe PDPH found only one in five reported less severe headache after either subcutaneous sumatriptan 6 mg or placebo  Avoid breast feeding 12h post exposure for sumatriptan excreted in breast milk  Frovatriptan has been found effective in PDPH at 2.5 mg/day for 5 days

 Cosyntropin or synthetic ACTH and hydrocortisone  stimulating the adrenal gland and increasing CSF secretion  Intravenous cosyntropin as well as hydrocortisone have been found to be effective in treating PDPH after failed EBP Randomized control studyoutcome 60 patients with PDPH following spinal anesthesia for cesarean section were given hydrocortisone for 48 significantly reduced the severity of PDPH in the study group 90 patients with ADP given iv Cosyntropin 1 mg reduced PDPH from 69 to 33%; and the need for EBP from 30% to 11%

Epidural Blood Patch (EBP)  Epidural blood patch was introduced by Gormley and popularized by Di Giovanni  Autologous blood is injected into the epidural space  spreads both cephalad and caudal and increases the pressure in the epidural space, compressing the thecal sac and increasing the CSF pressure  Immediate relief of the headache

 Blood coagulates, helped by the procoagulant effect of the CSF and occludes the hole in the dura, preventing further leakage of CSF  The mass effect gradually resolves over 7-13 h leaving a mature clot in the posterior epidural space.  fibroblastic activity and collagen formation, further securing closure of the dural perforation after a few days

 Recommendation that the EBP should not be performed too soon after dural puncture  Randomized study by Loeser found that performing EBP after 24 h reduced the failure rate from 71% to 4% in a study of 66 EBP  The initial outcome from an EBP is between 70 and 98%  Up to 40% need a second EBP and occasionally even a third  Contraindication:  Fever  Local infection  Coagulopathy

 Complication  Backache  Transient bradycardia  Radiculitis  Arachnoiditis  Aseptic meningitis  Cranial nerve paralysis  Seizures  Cauda equina syndrome  Permanent spastic paralysis  Recent Cochrane review concluded that EBP is beneficial for PDPH compared to conservative treatment

Technique  Under full aseptic precautions with 2 operators  Patient usually was put in the lateral position  The epidural space is identified, either at the level of original puncture or one space lower  Another operator perform a venepuncture and hands over the blood to be injected ( mls)  Blood slowly injected into the epidural space till the patient reports a feeling of pressure or pain in her back or legs.  Post procedure patient is advised to lie flat for at least 2h and avoid vigorous activity or straining for a few days

Case study  A 29 y.o. female G3P2. Antenatally with bronchial asthma, GDM on diet control & paraumbilical hernia.  Hx of LSCS under spinal in 1 st pregnancy – straght forward SA & epidural in labour during 2 nd pregnancy – multiple attempt (2 level attempt)  In early phase of labour & was referred by O&G team for obstetric analgesic service as requested by patient.  Upon attended p/s 4/10 during contraction & Os opening 3cm

 Proceed with epidural.  Was done in sitting position using midline approach with 18G tuohy needle  Noted bloody tap during 1 st attempt at L3L4 level. Abandoned the site & move on to 1 level above  2 nd attempt was done at L2L3 level & noted dural tap evidence by efflux of the CSF  Called in specialist in-charge. 3 rd attempt done at L3L4 level with blood stained catheter & flow is acceptable  At the moment of the dural tap patient c/o sudden headache. P/s about 4-5/10. Headache resolved after lie flat.

 Successfully delivered via SVD & discharge to ward with continuation of epidural anelgesia  Start c/o headache dependent on the posture. Headache worsening when sitting upright with p/s up to 7/10 a/w neck stiffness. Headache was described as diffuse headache from occipital, bifrontal & between the eyes. Lie flat alleviate the pain.  Epidural catheter was removed on d1 post delivery but postural headache persist.  Seen by pain specialist d2 post delivery & was decided for conservative management first by bedrest & analgesic.

 Explaination given regarding epidural blood patch procedure for definite treatment of PDPH but need to justify the benefit & risk of the procedure. Patient understood & keen to be discharged first & was given option for walk in TCA anesth clinic if pain worsening / not resolve in 1/52 duration.  Discharged home & came to anesth clinic the next day with c/o worsening headache with association with giddiness & nausea. During TCA the headache is persistent even on lie flat position with p/s 9-10/10. Otherwise no symptoms of cranial nerve palsy

 Patient agreed for epidural blood patch. Admitted & posted for the procedure on the same day of admission  EBP was done by 2 operators in OT under sterile technique  Attached to BP, SPO2 & ECG monitoring  Pt was put on sitting position with lower limb rested on a chair  Prophylaxis IV ceftriaxone 1g given before procedure  1 st attempt done at L2L3 level. Presence of LOR sensation but there was continuous leaking of CSF

 2 nd attempt was done at 2 level above L1L2. Still presence of CSF leak but minimal.  Venepuncture was done by another operator from left antecubital fossa under aseptic technique. Blood C&S was sent & the remaining blood injected into epidural space  After 6mls blood injected into epidural space & patient claimed headache resolving progressively from caudal to cranium direction  Neck stiffness  Occipital  Bifrontal  Between eyes

 2h post procedure patient claimed no more headache. p/s 0/10 & no other residual neurological symptoms

Take home message  PDPH is one of the major causes of headache in the postpartum period  Preventive measures for PDPH include:  the use of smaller gauge pencil-point needles for spinal blocks  epidural needles of 18 G or less  using saline rather than air for epidural space identification  ultrasound guidance

 ADP has incidence >50% for PDPH  Severe untreated PDPH can cause complications such as nerve palsies, subdural hematoma and cerebral venous thrombosis  EBP is an invasive procedure with its own complications as well as a failure rate of up to 30% - explaination given to patient must be conveyed properly

Thank you!