Table 2.

Lidocaine treatment characteristics and ICP response.

Reference	Lidocaine dose	Mean duration of lidocaine administration (days)	ICP response	Other primary/secondary outcomes	Adverse effects to lidocaine	Conclusions
Bedford et al. [6]	1.5 mg/kg IV bolus x1 (n = 10) Thiopental dose (n = 10) = 3 mg/kg IV x1	Single bolus dose	Lidocaine: decrease in mean ICP from 28 mm Hg to 13 mm Hg, with nadir reached at a mean 66 ± 10 sec Thiopental: decrease in mean ICP from 33 mm Hg to 14 mm Hg, with a nadir reached at a mean 48 ± 9 sec	Mean MABP decrease of 26 mm Hg with thiopental No MABP changes with lidocaine	None described	Lidocaine and thiopental are equally an effect in reduction of ICP via IV bolus, with lidocaine preserving systemic hemodynamics
Bedford et al. [7]	1.5 mg/kg IV bolus x1 (n = 10) Saline (n = 10) = same volume	Single bolus dose	Pretreatment with IV lidocaine led to a maximum mean ICP increase of 6 mm Hg and 4 mm Hg at 30 and 60 sec Saline placebo mean increase in ICP of 16 mm Hg and 13 mm Hg at 30 and 60 sec	MABP increase was less with lidocaine compared to placebo	None described	IV lidocaine during laryngoscopy leads to an attenuation of ICP elevation compared to saline.
Donegan and Bedford [8]	1.5 mg/kg IV bolus x1 Saline was given in the same volume as lidocaine  Patients received both therapies	Single bolus dose	Lidocaine presuction led to a mean increase in ICP of 3.4 ± 6.2 mm Hg and 1.8 ± 2.6 mm Hg in those on and off barbiturates during suctioning Saline placebo presuction led to a mean increase in ICP 19 ± 4.7 mm Hg and 5.7 ± 3.2 mm Hg in those on and off barbiturates during suctioning	No significant difference in MABP changes during suctioning	None described	Lidocaine presuctioning leads to an attenuation of ICP elevations compared to saline
∗Donegan et al. [9]	1.5 mg/kg IV bolus x1 Saline was given in the same volume as lidocaine  Patients received both therapies	Single bolus dose	Lidocaine pretreatment led to a significant attenuation in ICP elevation with suctioning	Not stated	None described	Lidocaine presuctioning leads to an attenuation of ICP elevations compared to saline
Grover et al. [10]	Three groups: Group 1 (n = 10): 1 mg/kg IV bolus x1 Group 2 (n = 10): 1.5 mg/kg bolus x1 Group 3 (n = 10): 2 mg/kg bolus x1	Single bolus dose	All groups displayed a significant decrease in ICP within 2 min of lidocaine administration Group 3 displayed a 37.5% reduction in mean ICP, and Group 1 displayed a 17.5% mean reduction	Group 3 was the only group to display significant drop in SBP	SBP decreased with 2 mg/kg IV bolus dose	IV lidocaine bolus leads to significant reductions in ICP High lidocaine dosing may lead to drops in SBP
Hamill et al. [11]	LT (n = 11): 4 mL 4% lidocaine endotracheal IV (n = 11): 1.5 mg/kg IV bolus x1	Single dose	IV lidocaine led to a significant decrease in baseline ICP with no elevations during laryngoscopy LT lidocaine failed to decrease ICP and all patients had a significant elevation in ICP during intubation	Significant HR and MABP increase in LT group	None described	IV lidocaine led to decrease in baseline ICP and attenuated ICP elevations during laryngoscopy
Hirayama et al. [12]	All had dexamethasone and glycerin, with n = 7 this therapy in isolation. Lidocaine (n = 7): 10% lidocaine continuous infusion at 1.5–3 mg/min Nitroglycerine (n = 7): 3–7 mcg/kg/min	Continuous infusion	The addition of lidocaine to glycerin therapy led to a reduction in ICP spikes, with a mean reduction in ICP of 8.9 mm Hg over 24 hours The addition of nitroglycerin to glycerin led to a mean reduction of ICP of 7.4 mm Hg over 24 hours	Not stated	None described	Both IV lidocaine and nitroglycerin in the presence of glycerin therapy lead to ICP reductions at 24 hours
Montarry et al. [13]	All patients underwent suctioning without lidocaine, then with IV, and finally with LT Lidocaine IV: 1.5 mg/kg of 2% lidocaine bolus x1 Lidocaine LT: 5% lidocaine	Single dose	No difference in the ICP over 6 min for no lidocaine, or either of the lidocaine routes, during suctioning. 10 patients had documented ICP > 20 mm Hg and had the same lidocaine treatment Lidocaine IV led to a mild reduction in ICP over 6 min by approx. 2 mm Hg LT lidocaine did not have any significant effect compared to baseline	No difference in CPP	Not described	Lidocaine IV or LT did not lead to a suppression of ICP during suctioning Lidocaine IV bolus during acute ICP elevations may lead to mild reduction in ICP.
Samaha et al. [14]	Lidocaine: 1.5 mg/kg IV x1 Esmolol: 1.5 mg/kg IV x1	Single dose	Postintubation ICP rose significantly in both groups Esmolol: increased from 11 ± 6 mm Hg to 17 ± 10 mm Hg Lidocaine: increased from 10 ± 6 mm Hg to 16 ± 9 mm Hg	Significant decrease in CPP in both groups during intubation Esmolol decreased from a mean of 92 to 62 mm Hg  Lidocaine decreased from a mean of 96 to 68 mm Hg  After intubation CPP increased to 99 ± 23 mm Hg and 99 ± 17 mm Hg in the esmolol and lidocaine groups	Not described	Both lidocaine and esmolol failed to attenuate the elevation in CPP and ICP after intubation
White et al. [15]	Every patient received all treatments during individual suctioning episodes Saline = 2 mL Fentanyl = 1 mcg/kg Thiopental = 3 mg/kg Lidocaine = 1.5 mg/kg + succinylcholine = 1.5 mg/kg Lidocaine LT alone = 1.5 mg/kg	Single bolus dose	Lidocaine/succinylcholine IV and thiopental lead to a mean decrease in ICP by 4–6 mm Hg but had no effect on the ICP during suctioning LT lidocaine had more effect at attenuating cough and ICP elevations during suctioning. However, during instillation it initiated coughing and led to ICP spikes Fentanyl had no effect on ICP	MABP not affected by any regimen	None described	Lidocaine IV leads to ICP reduction but not attenuation of cough mediated ICP spikes LT lidocaine may be superior in preventing coughing related ICP spikes
Yano et al. [16]	1.5 mg/kg IV bolus dose at the following intervals prior to suctioning: 1, 3, 5, 10, and 15 min LT lidocaine = 2 mL of 4% lidocaine across the same intervals	Single bolus doses	Neither IV of LT lidocaine lowered baseline ICP, but both suppressed ICP elevations with suctioning LT lidocaine led to a lower peak ICP compared to IV	Not stated	None described	Both IV and LT lidocaine suppress ICP elevations during suctioning

N = number of patients, mg = milligram, mcg = microgram, mL = milliliters, wt = weight, kg = kilogram, hr = hour, min = minute, HR = heart rate, MABP = mean arterial blood pressure, ICP = intracranial pressure, CPP = cerebral perfusion pressure, CSF = cerebrospinal fluid, mm Hg = millimeters of mercury, IV = intravenous, LT = laryngotracheal, TBI = traumatic brain injury, LD = lumbar drain, and sec = second. ^∗Donegan and Bedford [8] and Donegan et al. [9] are companion publications, with Donegan et al. [9] representing the meeting abstract published prior to the full manuscript [8]. The data from Donegan et al. [9] is not included in the synthesis of data and is only included in the tables for completeness.