Gabapentin attenuates the pressor response to direct laryngoscopy and tracheal intubation

Impact of Gabapentin on Postoperative Hypotension in Enhanced Recovery after Surgery Protocols for Microvascular Breast Reconstruction

Background

Enhanced recovery after surgery (ERAS) protocols have been associated with hypotensive episodes after autologous breast reconstruction. Gabapentin (Gaba), a nonopioid analgesic used in ERAS, has been shown to attenuate postoperative hemodynamic responses. This study assesses ERAS's impact, with and without Gaba, on postoperative hypotension after microvascular breast reconstruction.

Methods

Three cohorts were studied: traditional pathway, ERAS + Gaba, and ERAS no-Gaba. We evaluated length of stay, inpatient narcotic use [morphine milligram equivalents (MME)], mean systolic blood pressure, hypotension incidence, and complications. The traditional cohort was retrospectively reviewed, whereas the ERAS groups were enrolled prospectively after the initiation of the protocol in April 2019 (inclusive of Gaba until October 2022).

Results

In total, 441 patients were analyzed. The three cohorts, in the order mentioned above, were similar in age and bilateral reconstruction rates (57% versus 61% versus 60%). The ERAS cohorts, both with and without Gaba, had shorter stays (P < 0.01). Inpatient MME was significantly less in the ERAS + Gaba cohort than the traditional or ERAS no-Gaba cohorts (medians: 112 versus 178 versus 158 MME, P < 0.01). ERAS + Gaba significantly increased postoperative hypotensive events on postoperative day (POD) 1 and 2, with notable reduction after Gaba removal (P < 0.05). Across PODs 0-2, mean systolic blood pressure was highest in the traditional cohort, followed by ERAS no-Gaba, then the ERAS + Gaba cohort (P < 0.05). Complication rates were similar across all cohorts.

Conclusions

Postmicrovascular breast reconstruction, ERAS + Gaba reduced overall inpatient narcotic usage, but increased hypotension incidence. Gaba removal from the ERAS protocol reduced postoperative hypotension incidence while maintaining similar stay lengths and complication rates.

Gabapentin alleviates myocardial ischemia-reperfusion injury by increasing the protein expression of GABAARδ

Gabapentin is a commonly used analgesic in the clinic to reduce opioid consumption. It is well known that gabapentin can reduce cerebral ischemia-reperfusion injury (IRI). However, it remains unclear whether gabapentin can reduce myocardial IRI. Before the performance of myocardial ischemia and reperfusion (I/R), rats received gabapentin without or with an intravenous injection of PI3K inhibitor (LY294002), or an intraspinal injection of lentivirus-mediated GABA_ARδ-shRNA. The myocardial IRI were evaluated by calculating the infarction area, arrhythmia score and myocardial apoptosis. The activity of PI3K/Akt and the expression of GABA_ARδ were quantified by western blotting. The effect of gabapentin on myocardial I/R was further demonstrated in vitro by establishing oxygen-glucose deprivation and reoxygenation in cardiomyocytes. After I/R in vivo, there were significant increases in infarction area, arrhythmia and Bax protein expression in the myocardium, as well as a decrease of GABA_ARδ in the spinal cord. Meanwhile, I/R also decreased the protein expression of PI3K/Akt and Bcl-2. Gabapentin pretreatment successfully attenuated IRI including reducing the myocardial infarction area and apoptosis. This effect was abolished by both the systemic inhibition of PI3K/Akt and the intraspinal suppression of GABA_ARδ. However, gabapentin pretreatment failed to prevent cellular injury induced by OGD/R in cardiomyocytes. Therefore, the myocardial protective effect of gabapentin may be attributed to activating PI3K/Akt in the myocardium and upregulating GABA_ARδ in the spinal cord. Gabapentin achieved a potent protective effect on the myocardium during the course of routine clinical treatment.

Comparative Study of Gabapentin, Clonidine and Placebo in Alleviating the Hemodynamic Changes Due to Tracheal Intubation and Laryngoscopy

INTRODUCTION

Hemodynamic changes during laryngoscopy and tracheal intubation must be reduced for safe and effective anesthesia. The present study was conducted to compare the efficacy of oral clonidine, gabapentin and placebo in alleviating the hemodynamic changes due to tracheal intubation and laryngoscopy.

METHODS

This was a double-blinded randomized controlled trial conducted on 90 patients who were undergoing elective surgery and were randomized into three groups. Group I (n=30) received a placebo, group II (n=30) received gabapentin and group III (n=30) received clonidine as premedication before anesthesia induction. Patient heart rate and pressor response were recorded periodically and compared between the groups.

RESULTS

There was no significant difference in the baseline heart rate (HR) and mean arterial pressure (MAP) between the groups. HR elevation was observed in all three groups and found to be significant (p=0.0001) but the increase was higher in the placebo (15 min: 80.80± 15.41) and lower in the clonidine group (15 min: 65.53± 12.43). The elevation in systolic and diastolic blood pressure was least and transient in the gabapentin group, as compared to placebo and clonidine group. Intra-operatively, the requirement of opioids was higher in the placebo as compared to clonidine and gabapentin (p < .001).

CONCLUSION

Clonidine and gabapentin were effective in reducing the hemodynamic changes during laryngoscopy and intubation.

Effect of add-on Gabapentin premedication on hemodynamic response to skull pin insertion

Background and Aims:

Material and Methods:

Results:

Conclusion:

α2δ-1-Dependent NMDA Receptor Activity in the Hypothalamus Is an Effector of Genetic-Environment Interactions That Drive Persistent Hypertension

The interplay between genetic and environmental factors is critically involved in hypertension development. The paraventricular nucleus (PVN) of the hypothalamus regulates sympathetic output during stress responses and chronic hypertension. In this study, we determined mechanisms of synaptic plasticity in the PVN in chronic stress-induced persistent hypertension in male borderline hypertensive rats (BHR), the first offspring of spontaneously hypertensive rats and normotensive Wistar-Kyoto rats. In Wistar-Kyoto rats, chronic unpredictable mild stress (CUMS) increased arterial blood pressure (ABP) and heart rate, which quickly returned to baseline after CUMS ended. In contrast, in BHR, CUMS caused persistent elevation in ABP, which lasted at least 2 weeks after CUMS ended. CUMS also increased the mRNA level of α2δ-1 and synaptic protein levels of GluN1, α2δ-1, and α2δ-1-GluN1 complexes in the PVN in BHR. Furthermore, CUMS significantly increased the frequency of miniature EPSCs and the amplitude of NMDAR currents in spinally projecting PVN neurons in BHR; these increases were normalized by blocking NMDARs with AP5, inhibiting α2δ-1 with gabapentin, or disrupting the α2δ-1-NMDAR interaction with α2δ-1Tat peptide. Microinjection of AP5 or α2δ-1Tat peptide into the PVN normalized elevated ABP and renal sympathetic nerve activity in stressed BHR. In addition, systemically administered gabapentin or memantine attenuated higher ABP induced by CUMS in BHR. Our findings indicate that chronic stress-induced persistent hypertension is mediated by augmented sympathetic outflow via α2δ-1-bound NMDARs in the PVN. This new information provides a cellular and molecular basis for how the genetic-environment interactions cause persistent hypertension.SIGNIFICANCE STATEMENT Chronic stress is a major risk factor for hypertension development, especially for individuals with a genetic predisposition to hypertension. Using a rat model of borderline hypertension, we showed that chronic stress induced long-lasting hypertension and sympathetic nerve hyperactivity, which were maintained by NMDAR activation in the hypothalamus. Chronic stress also increased the expression of α2δ-1, previously regarded as a Ca2+ channel subunit, promoting physical interaction with and synaptic trafficking of NMDARs in the hypothalamus. Inhibiting α2δ-1, blocking NMDARs, or disrupting α2δ-1-bound NMDARs reversed chronic stress-induced sympathetic outflow and persistent hypertension. Thus, α2δ-1-dependent NMDAR activity in the hypothalamus is an effector of genetic-environment interactions and may be targeted for treating stress-induced neurogenic hypertension.

Effect of oral gabapentin premedication on hemodynamic parameters and postoperative pain in patients of laparoscopic cholecystectomy: A randomized double-blind controlled study

Background and Aims:

Carbon dioxide (CO₂) pneumoperitoneum created during laparoscopic cholecystectomy causes adverse hemodynamic changes such as rise in arterial pressure. The aim of this study was to assess the effect of oral gabapentin premedication on hemodynamic parameters in addition to postoperative nausea and vomiting (PONV) and pain in patients of laparoscopic cholecystectomy conducted under general anesthesia.

Material and Methods:

Randomly selected 60 American Society of Anesthesiologists (ASA) class I patients scheduled for laparoscopic cholecystectomy were premedicated with either gabapentin 1200 mg (Group GB) or placebo (Group PL) 2 h prior to induction of anesthesia. Anesthesia was induced with fentanyl, propofol, and vecuronium; and maintained with oxygen (33%), nitrous oxide (66%), and isoflurane (1%) with controlled ventilation. Hemodynamic parameters were recorded at various time intervals intraoperatively and during pneumoperitoneum every 10 min till 50 min. Postoperatively visual analog score (VAS) for pain, incidence of PONV, and sedation score were recorded for 6 h. The collected data were analyzed statistically by using repeated measures analysis of variance (ANOVA), Student's t test, Chi-square test, and Mann–Whitney U test.

Results:

Changes in mean BP, systolic BP, and diastolic BP from prepneumoperitoneum values were significantly less in group GB during pneumoperitoneum (P < 0.05) with no significant change in HR in both groups (>0.05). VAS score was significantly lower in group GB. The duration of analgesia and PONV free period were significantly higher in group GB (P < 0.01).

Conclusion:

Oral gabapentin premedication may be used to control hemodynamic parameters during pneumoperitoneum in patients undergoing laparoscopic cholecystectomy.

Comparison of Oral Clonidine and Gabapentin Premedication for Attenuation of Pressor Response to Laryngoscopy and Endotracheal Intubation

Background:

During the administration of general anesthesia, direct laryngoscopy and endotracheal intubation cause an increase in heart rate, arterial pressure, and dysrhythmias in upto 90% of patients. These changes can be particularly hazardous for patients with cerebral or coronary diseases. Both clonidine and gabapentin have been used for anesthetic effects, but a better drug for controlling hemodynamic parameters is being investigated.

Aims:

The study was done to evaluate and compare the efficacy of oral clonidine 0.3 mg and oral gabapentin 900 mg as a premedication for attenuation of pressor response to laryngoscopy and endotracheal intubation.

Materials and Methods:

After obtaining approval from the ethics committee, 75 patients, American Society of Anesthesiologists physical status classes I and II between the ages of 18 and 60 years scheduled to undergo elective noncardiac surgical procedure were enrolled in the study. Patients were randomized into three groups of 25 each who received 0.3 mg clonidine, 900 mg gabapentin, and placebo. The hemodynamic parameters were recorded at various time intervals along with any adverse effects.

Statistical Analysis:

Quantitative variables were compared using unpaired t-test between the two groups and ANOVA for three groups. Qualitative variables were compared using the Chi-square test/Fisher's exact test. P < 0.05 was considered statistically significant.

Results:

In our study, we found that both clonidine and gabapentin are effective premedicants by oral route 2 h before induction of anesthesia to blunt the hemodynamic response to laryngoscopy and intubation as compared to placebo. Between clonidine and gabapentin, clonidine was found to be more effective with respect to blunting of systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP), although found to be statistically significant only at 15 min with respect to SBP and DBP.

Conclusion:

Using clonidine or gabapentin, one can effectively provide stable hemodynamic conditions during laryngoscopy and endotracheal intubation, but more so with clonidine.

Preoperative gabapentin versus bisoprolol for haemodynamic and surgical field optimisation during endoscopic sinus surgery: A randomised controlled trial

Background and Aims:

Appropriate premedication can optimise haemodynamics and hence surgical field visibility during endoscopic sinus surgery (ESS). This study aimed to compare the intraoperative effect of gabapentin 1200 mg versus bisoprolol 2.5 mg, given 2 hours before ESS.

Methods:

Patients were assigned into one of three groups. Patients of gabapentin group received preoperative oral gabapentin 1200 mg while, patients of bisoprolol and control groups received oral bisoprolol 2.5 mg and placebo respectively 2 hours before ESS. Primary outcome: reduction of blood loss and surgical field quality. Secondary outcome: haemodynamic control. mean arterial pressure (MAP) and heart rate (HR) were recorded as baseline, before and after induction of anaesthesia, at 1, 5, 10, 15 minutes after intubation and then every 15 minutes until the end of surgery. Data also included Fromm and Boezaart category scale (assessed every 15 min), intraoperative blood loss, surgeon satisfaction score, intraoperative anaesthetic/analgesic and vasoactive medications requirements.

Results:

Out of 66 eligible patients, 60 patients completed the study. Intraoperative MAP and HR were significantly lower and more stable in gabapentin and bisoprolol groups compared to control group (p < 0.05). The volume of blood loss was significantly lower (p 0.000) and operative field was more visible in gabapentin and bisoprolol groups than those in control group (p 0.000).

Conclusion:

The beneficial effect of gabapentin 1200 mg on intraoperative haemodynamic control and surgical field visibility is comparable to that of bisoprolol 2.5 mg when either of them is given as a single oral dose 2 hours before ESS.

Oral Pregabalin as Premedication on Anxiolysis and Stress Response to Laryngoscopy and Endotracheal Intubation in Patients Undergoing Laparoscopic Cholecystectomy: A Randomized Double-Blind Study

Background

Direct laryngoscopy and tracheal intubation lead to increase in heart rate and blood pressure. This can cause serious complications in patients with coronary artery disease, reactive airways, or intracranial neuropathology. Preoperative anxiety is associated with greater level of postoperative pain. Attenuation of anxiety and hemodynamic response to laryngoscopy and intubation are cornerstone of better anesthetic outcome. Gabapentinoids (gabapentin and pregabalin) have been known to possess anxiolytic, analgesic, and anticonvulsant properties.

Aim

The aim of this study is to determine the effects of oral pregabalin on anxiolysis and attenuation of stress response to laryngoscopy and endotracheal intubation.

Study Design

This was a prospective randomized double-blind placebo controlled study.

Materials and Methods

A total of 60 patients ASA physical status Class I and II, undergoing elective laparoscopic cholecystectomy, were randomly allocated into two groups receiving either oral placebo or oral pregabalin 150 mg, 60 min before induction of anesthesia. Visual analog scale (VAS) for anxiety was recorded before, and 60 min after giving the drug. Hemodynamic parameters (heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial pressure) were recorded before, and 60 min after giving drug, during and 2, 4, 6, 8, and 10 min after intubation.

Results

During preinduction, pregabalin showed a decrease in VAS and attenuation of stress response to laryngoscopy and intubation compared to that of placebo. The premedicated patients were hemodynamically stable perioperatively without side effects.

Conclusion

Pregabalin is effective in attenuating preoperative anxiety and stress response to endotracheal intubation.

Regulation of sympathetic vasomotor activity by the hypothalamic paraventricular nucleus in normotensive and hypertensive states

The hypothalamic paraventricular nucleus (PVN) is a unique and important brain region involved in the control of cardiovascular, neuroendocrine, and other physiological functions pertinent to homeostasis. The PVN is a major source of excitatory drive to the spinal sympathetic outflow via both direct and indirect projections. In this review, we discuss the role of the PVN in the regulation of sympathetic output in normal physiological conditions and in hypertension. In normal healthy animals, the PVN presympathetic neurons do not appear to have a major role in sustaining resting sympathetic vasomotor activity or in regulating sympathetic responses to short-term homeostatic challenges such as acute hypotension or hypoxia. Their role is, however, much more significant during longer-term challenges, such as sustained water deprivation, chronic intermittent hypoxia, and pregnancy. The PVN also appears to have a major role in generating the increased sympathetic vasomotor activity that is characteristic of multiple forms of hypertension. Recent studies in the spontaneously hypertensive rat model have shown that impaired inhibitory and enhanced excitatory synaptic inputs to PVN presympathetic neurons are the basis for the heightened sympathetic outflow in hypertension. We discuss the molecular mechanisms underlying the presynaptic and postsynaptic alterations in GABAergic and glutamatergic inputs to PVN presympathetic neurons in hypertension. In addition, we discuss the ability of exercise training to correct sympathetic hyperactivity by restoring blood-brain barrier integrity, reducing angiotensin II availability, and decreasing oxidative stress and inflammation in the PVN.

α2δ-1 couples to NMDA receptors in the hypothalamus to sustain sympathetic vasomotor activity in hypertension

KEY POINTS

α2δ-1 is upregulated, promoting the interaction with NMDA receptors (NMDARs), in the hypothalamus in a rat model of hypertension. The prevalence of α2δ-1-bound NMDARs at synaptic sites in the hypothalamus is increased in hypertensive animals. α2δ-1 is essential for the increased presynaptic and postsynaptic NMDAR activity of hypothalamic neurons in hypertension. α2δ-1-bound NMDARs in the hypothalamus are critically involved in augmented sympathetic outflow in hypertensive animals.

ABSTRACT

Increased glutamate NMDA receptor (NMDAR) activity in the paraventricular nucleus (PVN) of the hypothalamus leads to augmented sympathetic outflow in hypertension. However, the molecular mechanisms underlying this effect remain unclear. α2δ-1, previously considered to be a voltage-activated calcium channel subunit, is a newly discovered powerful regulator of NMDARs. In the present study, we determined the role of α2δ-1 in regulating synaptic NMDAR activity of rostral ventrolateral medulla (RVLM)-projecting PVN neurons in spontaneously hypertensive rats (SHRs). We show that the protein levels of α2δ-1 and NMDARs in synaptosomes and the α2δ-1-NMDAR complexes in the hypothalamus were substantially higher in SHRs than in normotensive control rats. The basal amplitude of evoked NMDAR currents and NMDAR-mediated synaptic glutamate release in RVLM-projecting PVN neurons were significantly increased in SHRs. Strikingly, inhibiting α2δ-1 activity with gabapentin or disrupting the α2δ-1-NMDAR association with an α2δ-1 C-terminus peptide completely normalized the amplitude of evoked NMDAR currents and NMDAR-mediated synaptic glutamate release in RVLM-projecting PVN neurons in SHRs. In addition, microinjection of the α2δ-1 C-terminus peptide into the PVN substantially reduced arterial blood pressure and renal sympathetic nerve discharges in SHRs. Our findings indicate that α2δ-1-bound NMDARs in the PVN are required for the potentiated presynaptic and postsynaptic NMDAR activity of PVN presympathetic neurons and for the elevated sympathetic outflow in hypertension. α2δ-1-bound NMDARs may be an opportune target for treating neurogenic hypertension.

α2δ-1 Is Essential for Sympathetic Output and NMDA Receptor Activity Potentiated by Angiotensin II in the Hypothalamus

Both the sympathetic nervous system and the renin-angiotensin system are critically involved in hypertension development. Although angiotensin II (Ang II) stimulates hypothalamic paraventricular nucleus (PVN) neurons to increase sympathetic vasomotor tone, the molecular mechanism mediating this action remains unclear. The glutamate NMDAR in the PVN controls sympathetic outflow in hypertension. In this study, we determined the interaction between α2δ-1 (encoded by Cacna2d1), commonly known as a Ca²⁺ channel subunit, and NMDARs in the hypothalamus and its role in Ang II-induced synaptic NMDAR activity in PVN presympathetic neurons. Coimmunoprecipitation assays showed that α2δ-1 interacted with the NMDAR in the hypothalamus of male rats and humans (both sexes). Ang II increased the prevalence of synaptic α2δ-1-NMDAR complexes in the hypothalamus. Also, Ang II increased presynaptic and postsynaptic NMDAR activity via AT1 receptors, and such effects were abolished either by treatment with pregabalin, an inhibitory α2δ-1 ligand, or by interrupting the α2δ-1-NMDAR interaction with an α2δ-1 C terminus-interfering peptide. In Cacna2d1 knock-out mice (both sexes), Ang II failed to affect the presynaptic and postsynaptic NMDAR activity of PVN neurons. In addition, the α2δ-1 C terminus-interfering peptide blocked the sympathoexcitatory response to microinjection of Ang II into the PVN. Our findings indicate that Ang II augments sympathetic vasomotor tone and excitatory glutamatergic input to PVN presympathetic neurons by stimulating α2δ-1-bound NMDARs at synapses. This information extends our understanding of the molecular basis for the interaction between the sympathetic nervous and renin-angiotensin systems and suggests new strategies for treating neurogenic hypertension.SIGNIFICANCE STATEMENT Although both the sympathetic nervous system and renin-angiotensin system are closely involved in hypertension development, the molecular mechanisms mediating this involvement remain unclear. We showed that α2δ-1, previously known as a calcium channel subunit, interacts with NMDARs in the hypothalamus of rodents and humans. Angiotensin II (Ang II) increases the synaptic expression level of α2δ-1-NMDAR complexes. Furthermore, inhibiting α2δ-1, interrupting the α2δ-1-NMDAR interaction, or deleting α2δ-1 abolishes the potentiating effects of Ang II on presynaptic and postsynaptic NMDAR activity in the hypothalamus. In addition, the sympathoexcitatory response to Ang II depends on α2δ-1-bound NMDARs. Thus, α2δ-1-NMDAR complexes in the hypothalamus serve as an important molecular substrate for the interaction between the sympathetic nervous system and the renin-angiotensin system. This evidence suggests that α2δ-1 may be a useful target for the treatment neurogenic hypertension.

A comparison of haemodynamic responses between clinical assessment-guided tracheal intubation and neuromuscular block monitoring-guided tracheal intubation: A prospective, randomised study

BACKGROUND AND AIMS

Haemodynamic responses to laryngoscopy and endotracheal intubation and their hazards are well documented. The purpose of the study was to compare the effects of laryngoscopy and intubation on cardiovascular responses when the appropriate moment for intubation was directed by either clinical judgment or train-of-four assessment.

METHODS

A total of 68 patients, posted for laparoscopic cholecystectomy, were randomised into two groups. In Group M patients, the trachea was intubated after train of four counts became zero in adductor pollicis muscle, whereas in Group C patients, the trachea was intubated after the clinical judgment of jaw muscle relaxation. Changes in heart rate (HR) and mean arterial pressure, intubating conditions and the time between the administration of a neuromuscular blocking agent and endotracheal intubation were recorded. Results were analysed by the Analysis of variance and chi-square tests.

RESULTS

HR and mean arterial pressure were significantly higher in Group C as compared to Group M after laryngoscopy and tracheal intubation (P < 0.05). The mean time required for intubation was significantly shorter in Group C compared to Group M (175 ± 7 s vs. 385 ± 101 s). Excellent and good intubation conditions were observed in all Group M patients, whereas 24 out of 34 patients (70%) in Group C showed excellent and good intubation conditions.

CONCLUSION

Haemodynamic responses to laryngoscopy and tracheal intubation can be significantly attenuated if tracheal intubation is performed following complete paralysis of laryngeal muscles, detected by neuromuscular monitoring of adductor pollicis muscle.

Gabapentin for the hemodynamic response to intubation: systematic review and meta-analysis

PURPOSE

Endotracheal intubation is the gold standard for securing the airway before surgery. Nevertheless, this procedure can produce an activation of the sympathetic nervous system and result in a hemodynamic response which, in high-risk patients, may lead to cardiovascular instability and myocardial ischemia. The aim of this review was to evaluate whether gabapentin can attenuate this response and whether such an attenuation could translate into reduced myocardial ischemia and mortality.

SOURCE

We searched MEDLINE(®), EMBASE™, CINAHL, AMED, and unpublished clinical trial databases for randomized-controlled trials that compared gabapentin with control, fentanyl, clonidine, or beta blockers for attenuating the hemodynamic response to intubation. Primary outcomes were mortality, myocardial infarction, and myocardial ischemia. Secondary outcomes were hemodynamic changes following intubation.

PRINCIPAL FINDINGS

We included 29 randomized trials with only two studies at low risk of bias. No data were provided for the primary outcomes and no studies included high-risk patients. The use of gabapentin resulted in attenuation in the rise in mean arterial blood pressure [mean difference (MD), -12 mmHg; 95% confidence interval (CI), -17 to -8] and heart rate (MD, -8 beats·min(-1); 95% CI, -11 to -5) one minute after intubation. Gabapentin also reduced the risk of hypertension or tachycardia requiring treatment (risk ratio, 0.15; 95% CI, 0.05 to 0.48). Data were limited on adverse hemodynamic events such as bradycardia and hypotension.

CONCLUSION

It remains unknown whether gabapentin improves clinically relevant outcomes such as death and myocardial infarction since studies failed to report on these. Nevertheless, gabapentin attenuated increases in heart rate and blood pressure following intubation when compared with the control group. Even so, the studies included in this review were at potential risk of bias. Moreover, they did not include high-risk patients or report adverse hemodynamic outcomes. Future studies are required to address these limitations.

Oral clonidine and gabapentin suppress pressor response: A prospective, randomized, double blind study

Background:

Pressor response is a part of stress response caused by reflex sympathetic discharge due to direct laryngoscopy and tracheal intubation resulting in tachycardia, hypertension and arrhythmias. Both clonidine, and gabapentin administered orally can effectively blunt this detrimental hemodynamic response.

Aim:

To study the effect of oral clonidine to blunt the pressor response to direct laryngoscopy and to compare it with oral gabapentin. To observe for postoperative sedation and side effects if any.

Settings and Design:

Sixty patients of American Society of Anaesthesiologist Grade I and II scheduled for surgery under general anesthesia were considered in this prospective randomized double-blind study. They were randomly allocated into two groups of 30 each using computerized randomization.

Materials and Methods:

Group A was given oral clonidine 5 μg/kg and Group B was given oral gabapentin 800 mg. Both the drugs were given 90 min prior to surgery. Heart rate (HR) and blood pressure were monitored at baseline, 0, 1, 3, 5, 10, 15, and 30^th min of laryngoscopy. Sedation was monitored by Ramsay Sedation Scale score and side effects were noted.

Results:

HR decreased in both groups at 0 and 1 min, increased at 3^rd min and gradually decreased by 30^th min. Statistically, significant difference was found between two groups at 1, 3, 5, 10, and 15^th min (P < 0.05). Though there was no significant difference in systolic blood pressure, diastolic blood pressure and mean arterial pressure between the two groups, there was no rise in these parameters. Gabapentin produced more sedation than clonidine postoperatively, and few side effects were noted.

Conclusion:

Both oral clonidine and gabapentin are effective in obtunding pressor response to direct laryngoscopy, clonidine being better in terms of controlling HR. Gabapentin produces more postoperative sedation than clonidine.

Comparative evaluation of oral gabapentin versus clonidine as premedication on preoperative sedation and laryngoscopic stress response attenuation for the patients undergoing general anesthesia

Background:

Laryngoscopy and endotracheal intubation (L and I) is associated with rise in blood pressure (BP), heart rate (HR), leading to adverse cardiological outcome especially in susceptible individuals. To compare the BP, HR during L and I as well as to evaluate the preoperative sedation status between oral clonidine (Group C) and oral gabapentine (Group G) as premedication for the patients undergoing major surgery under general anesthesia (GA).

Materials and Methods:

From April 2008 to December 2009; in a prospective, double-blinded, and randomized controlled study; 100 adult patients of either sex, aged 20-45, of American Society of Anesthesiologists status I and II scheduled to undergo major surgery of >1 hour duration, randomly allocated into groups C and G were pre treated with oral clonidine (200 µg) and gabapentin (800 mg) respectively 2 h prior to induction. Preoperative sedation was assessed 2 h after premedication administration. Hemodynamic parameters were noted just before induction, during L and I 1,3,5,7, and10 min after intubation. The results obtained were then analyzed with statistical unpaired “t” test and Chi-square test and compared.

Results and Analysis:

Preoperative sedation between two groups were similar but group C attenuated HR, systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean blood pressure (MBP) more significantly before induction, during L and I, 1, 3, and 5 min, following L and I, while comparing with group G. Again gabapentin-reduced HR, BP, (SBP, DBP, MBP) significantly more at 7 and 10 min after L and I on comparison clonidine.

Conclusion:

Oral clonidine is equally effective in producing preoperative sedation in comparison to oral gabapentin, while on the contrary oral clonidine is more efficacious in reducing laryngoscopic stress response than oral gabapentin.

Comparative study of preoperative use of oral gabapentin, intravenous dexamethasone and their combination in gynaecological procedure

BACKGROUND

We studied the effects of oral gabapentin and intravenous (I.V.) dexamethasone given together or separately 1 h before the start of surgery on intraoperative hemodynamics Postoperative analgesia and postoperative nausea vomiting (PONV) in patients undergoing gynaecological procedure.

MATERIALS AND METHODS

Patients were randomly divided into three groups: Group 1 (gabapentin, n = 46) received 400 mg gabapentin, Group 2 (dexamethasone, n = 46) received 8 mg dexamethasone and Group 3 (gabapentin plus dexamethasone, n = 46) received both 400 mg gabapentin and 8 mg dexamethasone I.V. 1 h before the start of surgery. Standard induction and maintenance of anesthesia were accomplished. Visual analog scale for pain was recorded for 12 h. Side effects were noted.

RESULTS

Hemodynamics at various time interval (0, 5, 10, 15, 20, 25 and 30 min) of laryngeal mask airway insertion and PONV were found significantly lower in Group 3 than in Group 1 and Group 2 (P < 0.05). The average time to first postoperative analgesic requirement at (visual analogue score >3) was significantly longer in Group 3 (510.00 ± 61.64 min) than in Group 1 (352.83 ± 80.61 min) and in Group 2 (294.78 ± 60.76 min), (P < 0.05).

CONCLUSION

The present study concludes that the combination of oral Gabapentin and I.V. dexamethasone has significantly less hemodynamic changes, better postoperative analgesia and less incidence of PONV than individual administration of each drug.

A Survey on the Effect of Oral Gabapentin on Hemodynamic Changes During Direct Laryngoscopy and Tracheal Intubation and Intraoperative Bleeding in Patients Undergoing Septorhinoplasty

BACKGROUND

In patients undergoing septorhinoplasty, control of bleeding and hemodynamic variables is of great importance and laryngoscopy and tracheal intubation could be followed by a specific and transient increase in systemic blood pressure and heart rate.

OBJECTIVES

This study aimed to examine the effects of oral gabapentin on hemodynamic changes, during direct laryngoscopy, and the amount of bleeding in the patients undergoing septorhinoplasty.

PATIENTS AND METHODS

In a double-blind clinical trial, 103 patients (American society of anesthesiologists class I, II) aged 18 - 45 years old, who were septorhinoplasty candidates, were randomly assigned into two groups, a 900 mg gabapentin group and placebo, in Amir-Al-Momenin academic hospital. The drug was prescribed to the patients orally, 2 hours before the operation. Anesthetic technique was similar for all the patients. Heart rate (HR), systolic (SBP) and diastolic blood pressures (DBP), mean arterial blood pressure (MAP), oxygen saturation percentage of arterial blood (SaO2), before induction of anesthesia, 3, 5, 10, and 15 minutes after the intubation and tracheal extubation, and the amount of bleeding during operation were measured. Statistical analysis was performed with the SPSS (v. 16) software.

RESULTS

Variations in the HR, DBP and SaO2, in the specified time intervals, did not show any statistically significant difference, although variations in SBP were statistically significant (higher in gabapentin group). Regarding the average amount of bleeding volume, although there was a lower amount of bleeding in the gabapentin group, the difference was not statistically significant. Also, regarding the pain, there was no significant difference between the two groups in terms of visual analog scale (VAS) average and the received analgesic.

CONCLUSIONS

The present study showed that premedication with 900 mg gabapentin did not affect the hemodynamic changes induced by laryngoscopy and the amount of bleeding. However, the decreased amount of bleeding was observed in the gabapentin group.

Attenuation of the haemodynamic responses to tracheal intubation with gabapentin, fentanyl and a combination of both: A randomised controlled trial

Background and Aims:

We conducted a prospective, randomised, double-blind, controlled clinical trial to examine (1) whether a single preoperative dose of 800 mg gabapentin would be as effective as 2 μg/kg of intravenous (IV) fentanyl in blunting the haemodynamic response to tracheal intubation and (2) whether a combination of both would be more effective in this regard.

Methods:

Seventy-five patients (American Society of Anaesthesiologists physical status I), aged 20–50 years were allocated into one of three groups: 2 μg/kg IV fentanyl, 800 mg oral gabapentin or a combination of both. Gabapentin was administered 2 h and fentanyl 5 min before induction of anaesthesia, which was achieved with 5 mg/kg thiopentone, and tracheal intubation facilitated with 0.1 mg/kg vecuronium. Laryngoscopy lasting a maximum of 30 s was attempted 3 min after administration of the induction agents. Serial values of mean arterial pressure (MAP) and heart rate (HR) were compared among the three groups and with the respective preinduction measurements.

Results:

Patients receiving gabapentin 800 mg alone showed remarkable increases in HR and MAP in response to tracheal intubation (P < 0.05). The increases were similar for the other two regimens. These haemodynamic changes were lesser in patients receiving fentanyl and the combination of gabapentin and fentanyl.

Conclusion:

Oral gabapentin does not produce significant reduction in laryngoscopy and tracheal intubation induced sympathetic responses as compared to IV fentanyl or the combination of gabapentin and fentanyl.

Effect of melatonin and gabapentin on anxiety and pain associated with retrobulbar eye block for cataract surgery: a randomized double-blind study

Objectives:

To compare the effect of melatonin and gabapentin on anxiety, pain, sedation scores, and satisfaction of surgeon in patients of cataract surgery.

Materials and Methods:

One hundred thirty patients aged between 35 and 85 years scheduled for cataract surgery were randomly allocated to three study groups to receive melatonin (6 mg), gabapentin (600 mg) or placebo 90 min before arrival in the operating room. Pain, anxiety, and sedation scores during block and surgery as well as the surgeon's satisfaction with the surgery were assessed.

Results:

Anxiety scores decreased significantly in melatonin and gabapentin groups compared to the placebo group after premedication and extended to early postoperative period. The level of anxiety showed no statistically significant difference between melatonin and gabapentin groups at any time of measurement. There were significant differences between the pain scores during retrobulbar placement in gabapentin versus placebo (95% CI 3 to 4; P = 0.001) and melatonin (95% CI 3 to 4; P = 0.040) groups. Also, there were significant differences between the sedation scores during retrobulbar placement in gabapentin and placebo groups (95% CI 2 to 2.5; P = 0.046). The difference in sedation scores during retrobulbar placement in melatonin versus gabapentin and placebo groups was not significant. Neither the intraoperative pain scores nor the postoperative pain scores were different between the three groups. The surgeon reported similar quality of operation conditions during surgery for the three study groups.

Conclusion:

The level of anxiety was significantly lower with both anxiolytic drugs compared to placebo. Furthermore, gabapentin decreased the pain and improved the sedation scores only during retrobulbar placement compared to the placebo.

Oral clonidine versus gabapentin as premedicant for obtunding hemodynamic response to laryngoscopy and tracheal intubation

BACKGROUND

We compared the effects of oral clonidine and gabapentin as premedicant in obtunding hemodynamic response to laryngoscopy and intubation in normotensive patients undergoing elective surgery.

METHODS

A total of 100 patients of either sex enrolled in the study were randomly divided into two groups of 50 each. Group A patients received oral clonidine 200 μg and Group B patients received oral gabapentin 900 mg, 90 min prior to induction of anesthesia.

RESULTS

Both groups were matched for age, sex weight and intubation time. Anxiety score and sedation scores before induction were significantly better in Group A as compared with Group B. Heart rate rise was obtunded in Group A except at 1 min, as compared with Group B in which tachycardia persisted even at 3 and 5 min following intubation. Mean arterial pressure was maintained below baseline at all times in Group A as compared with Group B in which significant rise (+7.55%, P < 0.001) was seen at 1 min after intubation.

CONCLUSION

Oral clonidine provided good attenuation of hemodynamic response to laryngoscopy and intubation as compared with oral gabapentin.

Oral gabapentin premedication for elderly patients undergoing intraocular surgery

AIMS

To compare effects of gabapentin premedication with diazepam in patients undergoing cataract surgery.

METHODS

In a randomised double-blind study, the effects of gabapentin premedication as a sedative, anxiolytic, analgesic and oculohypotensive agent were studied in 56 elderly patients undergoing elective intraocular surgery.

RESULTS

There was significantly more sedation in the diazepam group than in the gabapentin group. However, there was less subjective anxiety in the gabapentin group than in the control group. There was a significant fall in intraocular pressure (IOP) and significant reduction in mean arterial pressure in the gabapentin group compared with the control group. Perioperatively, significantly more supplementation with intravenous midazolam was given in the control group than in the gabapentin group. A significantly larger number of patients in the gabapentin group scored a postanaesthesia recovery score of 10 compared with the control group. There was a statistically significant difference in the postoperative visual analogue scale scores for pain and number of analgesic requests with gabapentin scoring over diazepam in this regard.

CONCLUSIONS

Hence, premedication with oral gabapentin in these elderly patients undergoing elective intraocular surgery produced intraoperative anxiolysis, decreased sedation, a modest decrease in IOPs and improved postoperative recovery.

Effect of Two Different Doses of Gabapentin on the Intraocular Pressure and Hemodynamic Stress Responses to Laryngoscopy and Tracheal Intubation

Background. The stress response to laryngoscopy and intubation causes an undesirable increase in heart rate, blood pressure, and intraocular pressure. This study was designed to compare the effect of two doses of gabapentin on the stress response to laryngoscopy and intubation. Patients and Methods. (ASA I and II) 60 patients, aged from 18 to 60 years undergoing elective eye surgery requiring endotracheal intubation, were randomly allocated into 3 groups, 20 patients each. 2 hours before the surgery, group I received oral placebo, and groups II and III received oral gabapentin 800 mg and 1200 mg, respectively. Heart rate (HR), mean arterial pressure (MAP), and intraocular pressure (IOP) were measured before and after induction of anesthesia, immediately after, 5 minutes, and 10 minutes after intubation. Results. Gabapentin 1200 mg prevented the increase in HR, MAP, and IOP, secondary to laryngoscopy and intubation, and kept them below the baseline till 10 minutes after intubation (), while with gabapentin 800 mg, the increase in HR, MAP, and IOP was nonsignificant () and returned to levels below the baseline at 5 and 10 minutes after intubation. Conclusion. Preoperative gabapentin 1200 mg effectively prevented the stress response to laryngoscopy and intubation; meanwhile, gabapentin 800 mg only prevented significant stress response.

The prophylactic effects of gabapentin on postoperative sore throat after thyroid surgery

Background

Postoperative sore throat (POST) is considered a usual complication after tracheal intubation, especially, thyroid surgery. Gabapentin is a widely studied multimodal perioperative drug, which can be used to treat acute postoperative pain. The primary endpoints of this study was a reduction of the incidence of POST at rest and during the swallowing movements after thyroid surgery. And the second endpoints was a reduction of the intensity of the POST after thyroid surgery.

Methods

Seventy-one patients that underwent elective thyroid surgery received either gabapentin (Neurontin™ 600 mg) or placebo, orally, one hour before anesthesia. The VAS scores and incidences of POST and adverse effects were determined at 1 hr, 6 hr, 12 hr, and 24 hr after surgery at rest and during swallowing movement.

Results

The gabapentin group (N = 36) showed a lower incidence of POST than the placebo group (N = 35) (47% vs. 78%, P = 0.038), and had significant lower VAS score at 6 and 24 hours after surgery in the resting state. However, during the movement, no intergroup differences were found in terms of the incidence of POST (83% vs. 91%, P = 0.305) or VAS score. Furthermore, no significant difference was observed between the two groups, in adverse effects.

Conclusions

Gabapentin (Neurontin™ 600 mg) administered 1 hr before anesthesia reduced the intensity and incidence of POST during the resting state without a significant adverse event, during the 24 hr after thyroid surgery. However, gabapentin did not reduce the intensity and incidence of POST during the swallowing movement.

A randomized double-blind placebo-controlled clinical study on the effects of gabapentin premedication on hemodynamic stability during laparoscopic cholecystectomy

Background:

Carbon dioxide pneumoperitoneum for laparoscopic surgery increases arterial pressures, heart rate, and systemic vascular resistance. In this randomized double-blind placebo-controlled clinical study, we investigated the efficacy of gabapentin premedication to provide perioperative hemodynamic stability in patients undergoing laparoscopic cholecystectomy.

Materials and Methods:

Sixty patients, of either sex (18–65 years of age) undergoing elective laparoscopic cholecystectomy were randomly allocated to two groups of 30 patients each. Patients of group G received oral gabapentin 900 mg 2 h before induction of anesthesia, while patients in group P received placebo at the same time.

Results:

Mean arterial pressure in patients of group G were significantly lower (P < 0.05) after tracheal intubation and pneumoperitoneum and remained lower, as compared to group P, throughout the pneumoperitoneum. Similarly, heart rate in group G was significantly lower (P < 0.05) after tracheal intubation and pneumoperitoneum and remained lower, in comparison to group P, throughout the peumoperitoneum. Intravenous labetalol was required, to control intraoperative hypertension, in 33.3% (10 out of 30) patients in group P. There was no significant difference in the incidence of adverse effects between the two groups.

Conclusion:

Gabapentin premedication provided perioperative hemodynamic stability during laparoscopic surgery.

Oral pregabalin premedication for attenuation of haemodynamic pressor response of airway instrumentation during general anaesthesia: A dose response study

BACKGROUND

The airway instrumentation of direct laryngoscopy and tracheal intubation are powerful noxious stimuli that should be attenuated by appropriate premedication, smooth induction and rapid intubation. The present study evaluated the safe and clinically effective dose of oral pregabalin premedication for attenuation of haemodynamic pressor response of airway instrumentation.

METHODS

A total of 90 normotensive adult consented patients aged 24-56 years, ASA grade I and II, of both gender were randomized into three treatment groups of 30 patients each. Group I received oral placebo, Group II oral pregabalin 75 mg and Group III oral pregabalin 150 mg 1 h prior to induction. Anaesthetic technique was standardized and all groups were assessed for pre-operative sedation, haemodynamic changes after the premedication, before and after induction, after laryngoscopy and intubation, along with intraoperative haemodynamic stability and post-operative side-effects.

RESULTS

Pre-operative sedation levels were higher with pregabalin premedication. Significant increase in heart rate and mean arterial pressure was observed in Groups I and II after airway instrumentation, while statistically significant attenuation of mean arterial pressure was seen in Group III. No significant decrease in heart rate was observed in any group. None of the patient has suffered from any post-operative side-effects, and no significant differences in the parameters of recovery and awakening time were observed.

CONCLUSION

Oral pregabalin premedication has adequately sedated the patients. The haemodynamic pressor response of airway instrumentation was attenuated in a dose-related fashion. The premedicated patients were haemodynamically stable perioperatively without prolongation of recovery time and side-effects.

Gabapentin inhibits catecholamine release from adrenal chromaffin cells

BACKGROUND

Gabapentin is most commonly prescribed for chronic pain, but acute perioperative effects, including preemptive analgesia and hemodynamic stabilization, have been reported. Adrenal chromaffin cells are a widely used model to investigate neurosecretion, and adrenal catecholamines play important physiologic roles and contribute to the acute stress response. However, the effects of gabapentin on adrenal catecholamine release have never been tested.

METHODS

Primary cultures of bovine adrenal chromaffin cells were treated with gabapentin or vehicle for 18-24 h. The authors quantified catecholamine secretion from dishes of cells using high-performance liquid chromatography and resolved exocytosis of individual secretory vesicles from single cells using carbon fiber amperometry. Voltage-gated calcium channel currents were recorded using patch clamp electrophysiology and intracellular [Ca2+] using fluorescent imaging.

RESULTS

Gabapentin produced statistically significant reductions in catecholamine secretion evoked by cholinergic agonists (24 ± 3%, n = 12) or KCl (16 ± 4%, n = 8) (mean ± SEM) but did not inhibit Ca2+ entry or calcium channel currents. Amperometry (n = 51 cells) revealed that gabapentin inhibited the number of vesicles released upon stimulation, with no change in quantal size or kinetics of these unitary events.

CONCLUSIONS

The authors show Ca2+ entry was not inhibited by gabapentin but was less effective at triggering vesicle fusion. The work also demonstrates that chromaffin cells are a useful model for additional investigation of the cellular mechanism(s) by which gabapentin controls neurosecretion. In addition, it identifies altered adrenal catecholamine release as a potential contributor to some of the beneficial perioperative effects of gabapentin.

Effect of pretreatment with gabapentin on withdrawal movement associated with intravenous rocuronium injection

BACKGROUND

The major disadvantage of rocuronium is the withdrawal movement associated with its injection. The analgesic effect of perioperative gabapentin has been evaluated. We investigated the effects of gabapentin on the withdrawal movement induced by rocuronium injection.

METHODS

86 ASA physical status I or II patients, aged 18-69 years who were scheduled to undergo elective surgery with general anesthesia were enrolled. Patients were randomly allocated into two groups to receive either gabapentin 600 mg or placebo 2 hours prior to surgery. The patient's response to rocuronium injection was graded using a 4-point scale.

RESULTS

The incidence of withdrawal movement after rocuronium administration was significantly lower in the gabapentin group (55.0% in the control group vs 28.6% in the gabapentin group). The number of patients with generalized response indicating severe pain, was 9 (22.5%) in the control group and 3 (7.1%) in the gabapentin group.

CONCLUSIONS

Pretreatment with a single oral dose of gabapentin 600 mg reduced the incidence and severity of withdrawal movement after rocuronium administration.

Effect of oral gabapentin on the intraocular pressure and haemodynamic responses induced by tracheal intubation

BACKGROUND

Laryngoscopy and tracheal intubation may cause undesirable increases in blood pressure, heart rate (HR) and intraocular pressure (IOP). Gabapentin has been used effectively to attenuate the pressor response to laryngoscopy and tracheal intubation. We investigated whether the pre-treatment with gabapentin attenuates the IOP in addition to a haemodynamic response to tracheal intubation.

METHODS

Sixty ASA I-II patients were randomly allocated into two groups who received either gabapentin (800 mg) or placebo 2 h before surgery. IOP, mean arterial pressure (MAP) and HR were measured before and after the induction of anaesthesia as well as at 0, 1, 3, 5, 10 and 15 min following intubation.

RESULTS

IOP and MAP increased from baseline immediately after intubation in the placebo group (P=0.001 and 0.002, respectively). When compared with the placebo group, IOP values of the gabapentin group were significantly lower for the first 15 min after tracheal intubation (P=0.002 at 0 min, P=0.006 at 1 min, P<0.001 at 3 min, P<0.001 at 5 min, P<0.001 at 10 min and P=0.003 at 15 min) while MAP was lower in the first 10 min (P=0.001 at 0 min, P=0.002 at 1 min, P<0.001 at 3 min, P<0.001 at 5 min and P=0.028 at 10 min). These results showed that gabapentin effectively suppresses the increase in IOP secondary to endotracheal intubation and attenuates the increases in MAP.

CONCLUSION

It is suggested that gabapentin is a useful adjuvant in order to prevent an increase in the IOP in response to laryngoscopy and tracheal intubation.

The preoperative use of gabapentin, dexamethasone, and their combination in varicocele surgery: a randomized controlled trial

BACKGROUND

We investigated the effects of gabapentin and dexamethasone given together or separately 1 h before the start of surgery on laryngoscopy, tracheal intubation, intraoperative hemodynamics, opioid consumption, and postoperative pain in patients undergoing varicocele operations.

METHODS

Patients were randomly divided into four double-blind groups: group C (control, n = 20) received placebo, group G (gabapentin, n = 20) received 800 mg gabapentin, group D (dexamethasone, n = 20) received 8 mg dexamethasone, group GD (gabapentin plus dexamethasone) received both 800 mg gabapentin and 8 mg dexamethasone IV 1 h before the start of surgery. Standard induction and maintenance of anesthesia were accomplished and continued by propofol and remifentanil infusion. Heart rate and arterial blood pressure were recorded before induction and after intubation. Intraoperative total remifentanil consumption was recorded. Hemodynamic variables and visual analog scale were recorded for 24 h. Side effects were noted.

RESULTS

Hemodynamics at 1, 3, 5, and 10 min after tracheal intubation, total remifentanil consumption during surgery, postoperative visual analog scale scores at 30 min, 1, 2, 4, 6, and 12 h, and postoperative nausea and vomiting were found to be significantly lower in group GD than in group G and group D (P < 0.05 for both), and substantially lower when compared with group C (P < 0.001). All values in group C were also higher than in groups G and D (P < 0.05).

CONCLUSION

Gabapentin and dexamethasone administered together an hour before varicocele surgery results in less laryngeal and tracheal intubation response, improves postoperative analgesia, and prevents postoperative nausea and vomiting better than individual administration of each drug.

Gabapentin and pregabalin for chronic neuropathic and early postsurgical pain: current evidence and future directions

PURPOSE OF REVIEW

Gabapentin and pregabalin bind to the alpha-2-delta calcium channel subunit and represent a novel analgesic drug class. The evidence base supporting their use for chronic neuropathic and early postsurgical pain is reviewed.

RECENT FINDINGS

Multiple, large, high-quality trials have demonstrated the safety and efficacy of gabapentin and pregabalin in neuropathic pain. Treatment-related improvement of pain and sleep positively impact upon quality of life. Sedation, dizziness and ataxia are important and relatively common adverse effects, however. Accumulating evidence indicates that gabapentin, and possibly pregabalin, also exert important effects following surgery. Multiple high-quality trials have demonstrated analgesic and opioid-sparing efficacy with gabapentin following various surgical procedures. Gabapentin and pregabalin reduce movement-evoked pain and this can lead to enhanced functional postoperative recovery. Postoperative opioid sparing is of questionable relevance since few trials have shown reduced opioid-related adverse effects. Sedation, dizziness and ataxia have been reported in only a few trials. Future larger-scale perioperative trials focused on safety assessment are needed, however.

SUMMARY

Gabapentin and pregabalin are efficacious treatments for neuropathic and postsurgical pain. Future research addressing several specific questions would serve to better delineate their optimal roles in treating these and other pain conditions.