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Cerebrospinal fluid rhinorrhea management

Benefits-harm assessment: Benefits outweigh risk in large defects when using vascular flaps, balanced for small skull base defects. Value judgments: Surgeon preference. Recommendation level: Option. Intervention: Use of free or vascular grafts to repair small and large defects. Glues and sealants Dural sealants, fibrin glues, and related adjuncts are com monly used in endoscopic skull-base repair in an effort to maximize graft stability and seal the leak. Whether or not these adjuncts contribute to a successful repair is un clear. Following a literature search, 1 case control study was identified in which patients with CSF leaks were re paired with a pedicled nasoseptal flap with or without the use of a dural sealant. The authors saw no significant dif ference in leak recurrence between the 2 groups. 47 In vitro (n = 2) studies comparing various endoscopic repair strate gies found that burst pressure was significantly increased when a fibrin sealant was used in the repair compared to controls. 79, 80 In a randomized animal study, 10 pigs’ du ral leaks were repaired with or without fibrin glue, and then later assessed for pericranial graft adherence. The fib rin glue group had significantly better graft adherence and higher burst pressures. 81 Further human studies are neces sary to clarify the contribution of sealants in endoscopic CSF leak repair (Supporting material 7). Aggregate grade of evidence: C (Level 3b: 1 study). Benefit: Dural sealant or glue has no known benefit. Harm: None. Cost: Minimal to moderate. Benefits-harm assessment: Increased cost with unknown evidence in clinical studies. Value judgments: Surgeon preference. Recommendation level: Option. Intervention: Use of dural sealant or glue. Nasal packing Nasal packing is frequently used to support a graft in place following endoscopic repair of skull base CSF leaks. A re view of the literature identified only 1 study that discussed nasal packing, in addition to various other endoscopic re pair methods and adjunctive measures. In a meta-analysis, Hegazy et al. 4 noted that nasal packing was used in 61% of cases analyzed, and did not appear to have a significant effect on surgical outcome. Apart from this, there are no studies assessing the role of nasal packing in endoscopic re pair of CSF leaks. Further research is needed to determine whether packing is necessary following leak repair and, if so, if the type of packing or duration of packing affect outcomes (Supporting material 8). Aggregate grade of evidence: C (Level 2: 1 study). Benefit: Unknown benefit.

Harm: Discomfort, potential risk for toxic shock syndrome, and graft dislodgment. Cost: Minimal. Benefits-harm assessment: Packing may bolster repair, thereby, preventing graft dislodgement, limited to no evi dence to support practice. Value judgments: Surgeon preference. Recommendation level: Option. Intervention: Use of nasal packing in CSF leak repair. Bed rest following endoscopic repair of CSF leak is com monly prescribed to patients in an effort to prevent signif icant increases in intracranial pressure that could dislodge the graft. Our search did not identify any relevant articles on this topic, indicating a need for research in this area. Stringency of bed rest precautions (eg, strict bed rest vs bed rest with bathroom privileges) as well as length of bed rest are potential questions to be resolved. Aggregate grade of evidence: No evidence and therefore no specific recommendation can be made. CPAP It remains unclear when it is safe to restart a patient’s home CPAP for obstructive sleep apnea following endo scopic skull-base surgery. It is frequently withheld up to several weeks postoperatively because of concerns that the air pressure could dislodge the skull-base repair and poten tially cause acute pneumocephalus. No studies were found that elucidate risks, benefits, and the appropriate timeline for CPAP use following endoscopic repair of CSF fistula. Given that a significant number of CSF leak patients require CPAP, its appropriate use postoperatively is an important question to address in future research. Aggregate grade of evidence: No evidence and therefore no specific recommendation can be made. Return to unrestricted activity Patients are typically kept to very restricted activity following endoscopic repair of CSF leaks. As previously stated, this is to avoid significant increases in intracranial pressure too early that could cause the fresh graft to dislodge and fail. A search of the literature revealed 1 case series in which patients with normal CSF opening pressures were asked to Valsalva while their CSF pressures were measured by manometry. All patients were able to artificially increase their CSF pressures by greater than 25 cm H 2 O, going from a mean resting pressure of 14.6 cm H 2 O to a mean Valsalva pressure of 32.3 cm H 2 O. 82 It is not known what pressures a new repair can withstand before failing. In vitro and animal studies have been done by de Almeida et al. 79 in which pig pericranium grafts were used to repair dural fistulae with various methods, and then subjected to burst pressure testing. These various Postoperative management Bed rest

International Forum of Allergy & Rhinology, Vol. 6, No. 1, January 2016

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