How effective is the local anesthetic infiltration of pin sites prior to application of head clamps: A prospective observational cohort study of hemodynamic response in patients undergoing elective craniotomy

Comparison of the Efficacy of Sterile Silicone Studs Versus Lidocaine for the Attenuation of the Hemodynamic Response to Skull Pin Insertion: A Randomized Controlled Trial

BACKGROUND

Skull pin insertion causes hypertension and tachycardia that adversely affects cerebral hemodynamics. We compared the efficacy of sterile silicone studs (SS) and pin site infiltration with lidocaine in attenuation of the sympathetic response to skull pin insertion.

METHODS

Adult patients (N = 120) undergoing supratentorial craniotomy under general anesthesia were randomized to receive either medical-grade sterile SS or 2 mL of 2% plain lidocaine infiltration at each pin site. Hemodynamic (heart rate and mean arterial pressure) response to skull pin insertion at baseline and at 0, 1, 2, 3, and 5 minutes after skull pin insertion was compared. Requirement of rescue analgesia (fentanyl), complications such as pin-site bleeding, and surgeon satisfaction score were assessed.

RESULTS

Heart rate in the lidocaine group was significantly greater at 0, 1, 2, 3, and 5 minutes after pin insertion compared with the SS group (P < 0.05). Mean arterial pressure was also significantly higher in the lidocaine group at 0, 1, 2, and 3 minutes after pin insertion (P = 0.001, P = 0.01, P = 0.034, and P = 0.042) compared with the SS group. The number of patients requiring fentanyl [17/60 (28.3%) vs. 40/60 (66%), P = 0.001] was lower in the SS group. The incidence of pin site bleeding was also lower in the SS group, and surgeon satisfaction score was greater.

CONCLUSIONS

Sterile SS appear to be more effective than lidocaine infiltration in attenuating the hemodynamic response to skull pin insertion with minimal adverse effects. Further multicenter studies are necessary to conclusively establish the safety and efficacy of sterile SS.

A Comparative Study of Intravenous Dexmedetomidine with Local Infiltration of Ropivacaine in Attenuation of Stress Response to Skull Pin Insertion in Craniotomies

Objective  Skull pin insertion in patients undergoing craniotomies elicits hemodynamic and neuroendocrine stress response that may be deleterious to the patient. Various drugs and techniques have been documented in literature to abate this stress response. Against this background, we aimed to compare the efficacy of intravenous dexmedetomidine and local infiltration of ropivacaine for attenuation of stress response to pin insertion in craniotomies.

Methods  Eighty-eight adult patients undergoing craniotomy under general anesthesia from March 2019 to April 2020 requiring application of head holder were randomized into two equal groups. After intubation, 0.75 µg kg ⁻¹ of dexmedetomidine over 10 minutes through infusion was given in group D, while local infiltration at pin sites was done with 0.5% ropivacaine, 2 mL at each site in group R. Hemodynamic parameters and levels of serum cortisol, prolactin, and blood glucose were measured before and after pin insertion. Unpaired t -test for continuous variables and Mann–Whitney U test was used for nonnormally distributed variables.

Results  Heart rate was statistically similar between the two groups at all the observed time points. The difference in mean arterial pressure values between the two groups was found to be statistically significant only from 10 to 20 minutes after pin insertion being statistically similar at rest of the time points. Levels of serum glucose, cortisol, and prolactin values 30 minutes after pin insertion were statistically similar between both groups.

Conclusion  We concluded that both interventions are equally efficacious in attenuation of hemodynamic and stress response to head holder application in patients undergoing craniotomies.

The Mayfield Skull Clamp: A Literature Review of Its Complications and Technical Nuances for Application

BACKGROUND

The Mayfield skull clamp is the most commonly used 3-pin head immobilization device. It is routinely used in cranial neurosurgical procedures and selected cervical procedures. Despite its role in some serious complications, guidelines and nuances on the correct application of the Mayfield clamp are lacking. The goal of this article was to present an overview of the complications associated with the Mayfield skull clamp. We also present a conceptual framework of the correct use-in our opinion-of the Mayfield clamp in several standard approaches to avoid the most common complications.

METHODS

PubMed was searched for original articles published between 1980 and 2020 with the search terms "Mayfield skull clamp" and "Mayfield head clamp." Eligibility criteria were availability of English abstract and complications clearly attributed to the Mayfield skull clamp. Both authors assessed all search results for eligibility. Additional articles were found with cross-references.

RESULTS

The most common complications associated with Mayfield clamp application were due to vascular injury inflicted by the pins or skull fractures. Complications related to use of the Mayfield clamp were rare but often serious and avoidable. A conceptual framework was presented on how to avoid these complications.

CONCLUSIONS

Attention to detail, anatomy, and the primum non nocere principle are imperative in every step of the neurosurgical pathway, including placement of the Mayfield skull clamp. Thoughtful application, taking into consideration several nuances, is recommended to avoid inadvertent patient harm.

Sphenopalatine ganglion block: Intranasal transmucosal approach for anterior scalp blockade - A prospective randomized comparative study

Background and Aims:

Peripheral nerve blocks in neurosurgical practice attenuate most stressful responses like pin insertion, skin, and dural incision. Scalp block is conventionally the blockade of choice. Further studies for less invasive techniques are required. Intranasal transmucosal block of the sphenopalatine ganglion has shown promising results in patients with chronic headache and facial pain. The primary objective of our study was to compare the gold standard scalp block and bilateral sphenopalatine ganglion block (nasal approach) for attenuation of hemodynamic response to pin insertion. Secondary objectives included hemodynamic response to skin and dural incision.

Material and Methods:

After IRB approval and informed consent, a prospective randomized comparative study was carried out on 50 adult patients undergoing elective supratentorial surgery. The hemodynamic response to pin insertion, skin incision, and dural incision was noted in both the groups. The data was analyzed with NCSS version 9.0 statistical software.

Results:

The HR and MAP were comparable between the groups. Following dural incision MAP was significantly lower at 1,2,3,4,5 and 10 min in group SPG whereas in group S it was significantly lower at 1 and 2min. (P = 0.02 at T1, P = 0.03 at T2).

Conclusions:

Concomitant use of bilateral SPG block with general anesthesia is an effective and safe alternative technique to scalp blockade for obtundation of hemodynamic responses due to noxious stimulus during craniotomy surgeries.

A novel temporary cranial fixation device for awake cranial surgery: Technical report of 14 cases

Background

Awake craniotomy has become the gold standard in various cranial procedures. As part of the awake technique, three-point pin fixation of the patient's head is important. One of the issues we encountered is the problem of matching the scalp infiltration site with the final pin position. To overcome this problem, we developed a flat plunger type fixator that adapts to the Mayfield holder.

Methods

Our fixator has a 2.5 cm metallic shaft that articulates in a ball and socket joint to allow its concave surfaces to adapt to the patient's scalp. After placing the patient in the desired position, the head is fixed with the three plungers, circles are drawn around each plunger, and they are then removed for the circles to be infiltrated with bupivacaine. Standard fixation pins are then placed in the Mayfield holder and aimed at the center of the circles.

Results

So far, we have operated on 14 patients with this technique. No patient experienced pain during temporary fixation, and the drawn circles ensured that there were no mismatches between the local anesthetic and pin locations. The technique was particularly useful on hairy scalps, where infiltration sites were hidden. We also used only 22.5 mg bupivacaine at the pin sites, freeing a dose for the field block around the scalp incision.

Conclusion

The temporary plunger type fixator provided a simple method to economize on local anesthetic use, check the patient's head position before final fixation, and ensure that the Mayfield pins matched with the anesthetized area.

Analgesia nociception index and hemodynamic changes during skull pin application for supratentorial craniotomies in patients receiving scalp block versus pin-site infiltration: A randomized controlled trial

Background:

Noxious stimulation such as skull pin insertion for craniotomy elicits a significant hemodynamic response. Both regional analgesic techniques (pin-site infiltration [PSI] and scalp block [SB]), and systemic strategies (opioids, alpha-2 agonists, anesthetics, and beta-blockers) have shown to attenuate this response. Analgesia Nociception Index (ANI) provides objective information about the magnitude of nociception and adequacy of analgesia. This study compared ANI and hemodynamic changes in patients receiving local anesthetic SB versus PSI during skull pin application for craniotomy.

Materials and Methods:

Sixty adult patients scheduled for elective supratentorial tumor surgery were randomly allocated to receive local anesthetic SB or PSI for skull pin insertion after the induction of anesthesia. Data regarding heart rate (HR), blood pressure (BP), and ANI were collected every minute for 5 min after the skull pin insertion beginning from the baseline.

Results:

A significant difference was observed in ANI values between the SB (higher ANI) and the PSI groups during skull pin insertion, P < 0.001 and P = 0.003 for ANIi and ANIm, respectively. Similarly, a significant difference was seen in HR and BP both within and between the two groups during skull pin insertion (P < 0.001 for both). The magnitude and duration of change were smaller in the SB group compared with the PSI group for the parameters studied. A strong negative linear correlation was noted between ANI and hemodynamic parameters.

Conclusions:

The changes in HR, BP, and ANI were significantly less with local anesthetic SB compared with PSI during skull pin insertion in patients undergoing supratentorial craniotomy.

Low Dose Dexmedetomidine Attenuates Hemodynamic Response to Skull Pin Holder Application

Background:

The application of skull pin holder elicits an adverse hemodynamic response that can be deleterious; there are many drugs that have been used to attenuate this response. We have conducted this study to evaluate the efficacy of intravenous (i.v.) dexmedetomidine on attenuation of hemodynamic responses to skull pin head holder application and to compare the effectiveness of two doses of i.v. dexmedetomidine (1 μg/kg and 0.5 μg/kg bolus).

Materials and Methods:

Ninety American Society of Anesthesiologists physical Status I–III patients undergoing craniotomy were randomized into three groups of thirty each. After intubation, patients in Group A received 1 μg/kg of i.v. dexmedetomidine, Group B received 0.5 μg/kg of i.v. dexmedetomidine, whereas Group C received an equivalent quantity of normal saline. Hemodynamic parameters were monitored regularly after skull pin insertion.

Results:

There was no significant difference in the monitored hemodynamic parameters among the three groups from baseline until intubation. Heart rate (HR) and mean arterial pressure (MAP) increased significantly at skull pin insertion and subsequent points in Group C, whereas the values decreased in Groups A and B (P < 0.05). Patients in Group A showed a higher and sustained attenuation of MAP. Patients in Group C had a higher incidence of tachycardia and hypertension requiring additional measures to attenuate the response.

Conclusions:

Dexmedetomidine in either dosage (1 μg/kg or 0.5 μg/kg) was effective in attenuating hemodynamic response to skull pin insertion. Dexmedetomidine in doses of 0.5 μg/kg was as effective in attenuating the HR and MAP response to skull pin insertion as compared to a dose of 1 μg/kg.

Comparison of intravenous labetalol and bupivacaine scalp block on the hemodynamic and entropy changes following skull pin application: A randomized, open label clinical trial

Background:

The application of skull pins in neurosurgical procedures is a highly noxious stimulus that causes hemodynamic changes and a rise in spectral entropy levels. We designed a study to compare intravenous (IV) labetalol and bupivacaine scalp block in blunting these changes.

Patients and Methods:

Sixty-six patients undergoing elective neurosurgical procedures were randomized into two groups, L (labetalol) and B (bupivacaine) of 33 each. After a standard induction sequence using fentanyl, propofol and vecuronium, patients were intubated. Baseline hemodynamic parameters and entropy levels were noted. Five minutes before, application of the pins, group L patients received IV labetalol 0.25 mg/kg and group B patients received scalp block with 30 ml of 0.25% bupivacaine. Following application of the pins, heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), and response entropy (RE)/state entropy (SE) were noted at regular time points up to 5 min.

Results:

The two groups were comparable with respect to their demographic characteristics. Baseline hemodynamic parameters and entropy levels were also similar. After pinning, the HR, SAP, DAP, MAP, and RE/SE all increased in both groups but were lower in the scalp block group patients. HR increased by 19.8% in group L and by 11% in group B. SAP increased by 11.9% in group L and remained unchanged in group B. DAP increased by 19.7% in group L and by 9.9% in group B, MAP increased by 15.6% in group L and 5% in group B (P < 0.05). No adverse effects were noted.

Conclusion:

Scalp block with bupivacaine is more effective than IV labetalol in attenuating the rise in hemodynamic parameters and entropy changes following skull pin application.