Trepanation revisited in COVID-19 era: A perspective on craniotomy during current pandemic, surgical technique, and complications avoidance

Abstract

Background: Craniotomy creates maximum aerosols threatening the health care workers (HCWs) of operation room. The technique of trepanation and measures to avoid complications has never been described in the literature. The time taken for craniotomy by different instruments has also never been compared.

Methods: The study included only COVID-positive patients who underwent surgery. Craniotomy was performed using trephine, pneumatic/power drill (PD), and Hudson brace-Gigli saw (HB-GS). Trepanation as done in 32 patients. The generation of aerosols and time taken for craniotomy by these instruments was observed. The droplet spread over a waterproof graph paper of 10 × 10 sq. cm was calculated in 13 cases of all the three craniotomy methods. The technique of trepanation and maneuvers to overcome complications was discussed.

Results: There was a gross difference in aerosol production and soiling of the surgical drapes, floor, surgeon's glove, gowns, face shield, goggles, etc. The average number of droplet aerosol in trepanation group was 4.76, 23.6 in drill and 21.3 in Gigli saw method. The average time taken for trepanation, PD, and HB-GS craniotomy was 4.8, 22.8, and 24.4 min, respectively. One mortality secondary to COVID was noted. All the HCWs assisting trepanation were negative for COVID-19 during postoperative follow-up of 7 days. However, 13 members of the surgical team which assisted in electric drill and HB-GS methods were COVID-positive.

Conclusion: Trepanation should be the preferred method of craniotomy during COVID-19 pandemic as it is associated with the least aerosolization and is the most time efficient.

Keywords: Aerosol; COVID-19; Craniotomy time; Trepanation; Trephine.

Figure 1:

NCCT head showing right frontal extradural hematoma (EDH) crossing midline an extending toward left (a), intraoperative photographs exposure of the right frontal bone (b), trephination in situ (c), EDH seen (d), the central pinhole on the outer cortex of the bone flap which is an initial fixation point for trepan (e), EDH evacuated and bone flap fixed using sutures (f), postoperative CT scan showing resolution of EDH (g), and postoperative 3D reconstructed image (h).

Figure 2:

The left-sided frontotemporoparietal acute SDH with mass effect (a), intraoperative view of exposure and trephination (b and c), acute SDH seen (d), SDH evacuated and brain lax (e), bone flap secured using sutures (f and g), postoperative CT shows resolution of SDH and mass effect (h), and 3D bone flap in situ (i). SDH: Subdural hematoma.

Figure 3:

CT shows hypointense lesion in the right parietotemporal region with perilesional edema. The MRI was suggestive of a mass which was hypo on T1 and hyper on T2 sequence with heterogeneous enhancement on contrast. The findings were consistent with high-grade glioma (upper two rows). The lower row shows gross total excision of tumor on postoperative CT scan and 3D bone flap in situ. Intraoperative images showing trepanation over parietal bone (a), bone flap being lifted (b), craniotomy and bone flap (c and d), bone flap fixed using miniplates and screws (e), and 3D reconstructed image shows well-fixed bone flap in postoperative scan (f).

Figure 4:

NCCT head shows subarachnoid hemorrhage with intracerebral hemorrhage in the right posterior frontal lobe (a), M3 middle cerebral artery aneurysm seen on CT angiography (b-d), intraoperative FST exposure with trepan (e and f), status post craniotomy (g), bone flap fixed using plates and screws (h), and operative field neat and clean during entire procedure (i).

Figure 5:

(A). The trephine craniotomy instrument set. The trepan, osteotomes, mallet, Hudson brace handle, and dissectors (a), various sizes of trepan (b), trepan with graduations over it (c), the centering drill, sharp, and blunt (d), and blunt pin in situ (e). (B). Assembling the trepan. (a) Parts of trepan showing high-speed cutting blade (star), dural guard (triangle), and fixator (arrow). Dural guard and fixator successively assembled and being mounted on Hudson brace handle (b-f).

Figure 6:

(A). The operative field during Gigli saw craniotomy. Extensive aerosol production is quite obvious. The settled heavier particles seen over surgeon and assistants’ gown and surrounding areas. The saw wire carries fine droplets of blood and bone dust with itself which keeps spreading with every cutting movement. The image is taken when craniotomy is not even completed. The field was much worse than the presented image. (B). Intraoperative image showing frontal (left arrow) and temporal bone (right arrow) with temporalis reflected. The contours of both bones are not favorable for trepanation. The superior temporal line (star) forms an angulation between frontal and temporal region. However, by changing the working axis of the instrument, trepanation is still feasible (a), sphenoidal ridge area which is inaccessible to jaws of trephine because of its curvature (b), to overcome the inaccessibility of frontosphenotemporal area, the author makes burr hole over sphenoidal ridge covered with bone dust (left arrow). This burr hole was used for dural separation and acted as anchor site for osteotome in making posteroinferior temporal cut (right arrow) which could not be made using trepan (c).