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When the Drain Hits the Brain
Original Article
When the Drain Hits the Brain Maria Kamenova1, Stefan Wanderer2, Patrick Lipps3, Serge Marbacher2, Luigi Mariani1,3, Jehuda Soleman1,3
BACKGROUND: The insertion of a subdural drain (SDD) after burr-hole drainage of chronic subdural hematoma (cSDH) was shown to reduce recurrence rate and improve outcome at 6 months. However, studies analyzing the rate of drain misplacement and complications associated with drain misplacement are sparse.
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METHODS: We analyzed retrospectively a cohort of consecutive patients undergoing burr-hole drainage for cSDH in 2 institutes. Drain type (subperiosteal drain vs. SDD), drain misplacement rate, and drain-associated complications were analyzed. We explored potential risk factors for drain misplacement and associated complications in the SDD subgroup using univariate and multivariate analysis. Drain misplacement was defined as incorrect drain position exceeding the subdural cavity and was categorized into drain misplacement without radiologic sequelae, drain misplacement causing radiologically confirmed iatrogenic bleeding, and drain misplacement causing neurologic symptoms.
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RESULTS: Of 463 included patients, 290 (62.6%) received an SDD. Drain misplacement occurred in 73 patients (15.8%). In 5 (6.9%) and 9 (12.3%) of these patients, iatrogenic bleeding and neurologic symptoms occurred, respectively. Intake of vitamin K antagonists (odds ratio [OR], 3.64) or different oral anticoagulants (OR, 10.24), and low preoperative Glasgow Coma Scale score (OR, 7.81) remained associated risk factors for drain misplacement
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Key words Burr-hole drainage - Chronic subdural hematoma - Iatrogenic brain injury - Subdural drain - Surgical technique - Traumatic brain injury -
Abbreviations and Acronyms CI: Confidence interval cSDH: Chronic subdural hematoma CT: Computed tomography DOACS: Different oral anticoagulants GCS: Glasgow Coma Scale MLS: Midline shift OR: Odds ratio
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after multivariate analysis. Patients with misplaced drains showed a strong association with postoperative bleeding (OR, 5.81), longer operation time (OR, 1.01), and hospitalization time (OR, 1.08) after multivariate analysis. CONCLUSIONS: The occurrence of SDD misplacement is unignorable, because it leads to iatrogenic drain-associated complications and seems to affect bleeding events and hospitalization time of patients undergoing burr-hole drainage of cSDH.
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INTRODUCTION
T
he standard treatment for patients with symptomatic chronic subdural hematomas (cSDHs) is burr-hole drainage and the insertion of a subdural drain (SDD).1 SDD insertion reduces the rate of hematoma recurrence2; however, the consequences of drain misplacement can be devastating.3 Because of the proximity to the brain, the insertion of an SDD is risky and may carry higher perioperative rates of seizures and iatrogenic bleeds.3,4 Studies analyzing the rate of drain misplacement, possible risk factors, and hematoma characteristics associated with a higher rate of drain misplacement are sparse. The aim of this study is to investigate the rate of drain misplacement and its complications, as well as possible factors associated with drain misplacement in a large cohort of patients undergoing burr-hole drainage of symptomatic cSDH.
SDD: Subdural drain SPD: Subperiosteal drain VKA: Vitamin K antagonists From the 1Department of Neurosurgery, University Hospital of Basel, Basel; 2Department of Neurosurgery, Kantonsspital Aarau, Aarau; and 3Faculty of Medicine, University of Basel, Basel, Switzerland To whom correspondence should be addressed: Maria Kamenova M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2020) 138:e426-e436. https://doi.org/10.1016/j.wneu.2020.02.166 Journal homepage: www.journals.elsevier.com/world-neurosurgery Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2020 Elsevier Inc. All rights reserved.
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2020.02.166
ORIGINAL ARTICLE MARIA KAMENOVA ET AL.
METHODS We retrospectively included 463 consecutive patients undergoing burr-hole drainage for cSDH between January 2013 and November 2017 at our institutions (245 patients [52.9%] at Kantonsspital Aarau and 218 patients [47.1%] at University Hospital of Basel). The diagnosis of all patients was symptomatic, 1-sided, or bilateral cSDH, confirmed by computed tomography (CT) or magnetic resonance imaging. Hematoma volume was estimated with the formula A B C/2. All patients were treated surgically with burr-hole trepanation (460 patients [99.4%] with 2 burr holes and 3 patients [0.6%] with 1 burr hole), irrigation of the hematoma, and insertion of a passive SDD (n ¼ 290, 62.6%) or subperiosteal drain (SPD) (n ¼ 171, 36.9%). In all cases, a Jackson Pratt drain (a closed drain consisting of an internal drain connected to a grenade-shaped bulb via plastic tube) was inserted for 48 hours. During this period, we kept the patients flat, and the bulb was placed at the level of the head without suction (passive drainage). Patients who presented with an acute subdural hematoma and those who underwent a craniotomy were excluded from the study. Medical records and radiologic studies were reviewed for clinical variables such as age, sex, side of hematoma, hematoma characteristics, comorbidities, concomitant blood thinners, surgery time, length of stay, morbidity, mortality, and outcome. Patients’ characteristics are summarized in Supplementary Table 1. We primarily analyzed the rate of drain misplacement, and drain-associated complications within the whole cohort and then compared these variables between the 2 different drain groups (SDD and SPD). Drain misplacement was defined as incorrect drain position exceeding the subdural cavity and was categorized into drain misplacement without radiologic sequelae, drain misplacement causing radiologically confirmed iatrogenic bleeding, and drain misplacement causing neurologic symptoms. Drain misplacements and associated complications were assessed on the routinely performed CT scan on the first postoperative day, before drain removal. Secondary outcome measures included intracranial bleeding, not clearly associated with drain misplacement, within the 2 groups, possible risk factors (within the SDD group) potentially associated with drain misplacement, the association of drain misplacement with outcome, and potential risk factors for postoperative intracranial bleedings not clearly associated with drain misplacement were analyzed in univariate and logistic regression multivariate analysis. Methods were applied according to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement. The study protocol was approved by the local ethics committee (EKNZ, Basel, Switzerland); because of the retrospective nature of the study, the review board waived the need for informed consent. All statistical analyses were performed using SPSS version 21.0 (IBM Corp., Armonk, New York, USA). Contingency tests were performed using a c2 or Fisher exact test; for nonparametric tests, the Mann-Whitney U test was used. Variables showing P < 0.1 on univariate analysis were included in the logistic regression multivariate analysis. P < 0.05 was considered significant. Methods applied were applied according to the STROBE statement.
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DRAIN MISPLACEMENT AFTER BURR-HOLE DRAINAGE
RESULTS Drain Misplacement Rate, Morbidity, Mortality, and Clinical Outcome The overall drain misplacement rate was 15.8% (n ¼ 73); of these, 6.9% (n ¼ 5) caused iatrogenic bleedings and 12.5% (n ¼ 9) caused neurologic symptoms. Of the 3 patients who were treated with a single burr hole, one had an asymptomatic misplaced drain touching the cortex. Mean follow-up time of the whole cohort was 48.20 (48.39) days after surgery. The SPD group had a significantly longer mean follow-up time of 55.05 (56.79) days, compared with the SDD group, with a mean follow-up time of 43.95 (42.05) days (P ¼ 0.006). Follow-up data at the time of hospital discharge were available for 456 patients (98.5%) (285 patients [98.3%] from the SDD group and 169 patients [98.8%] from the SPD group), whereas at the last follow-up for 385 patients (83.2%) follow-up data were available (235 patients [81.0%] from the SDD group and 148 patients [86.5%] from the SPD group). Morbidity, mortality, and clinical outcome of the whole cohort are presented in Supplementary Table 2. When comparing both groups (SDD and SPD), most baseline characteristics were similarly distributed and are presented in Table 1. In the SDD group, significantly more patients had arterial hypertension, whereas in the SPD group, significantly more patients had coronary artery disease. Concerning hematoma characteristics, in the SDD cohort, midline shift (MLS) and hematoma volumes were significantly larger (7.2 mm3 4.3 vs. 6.3 mm3 4.1, P ¼ 0.04 and 120 mm3 72.7 vs. 97.2 mm3 52.2, P ¼ 0.001, respectively). Drain misplacement occurred in 25.4% (n ¼ 73) of the patients from the SDD group, whereas in the SPD group, no drain misplacement was seen (P < 0.001). Recurrence rates were comparable (SPD, 9.9% and SDD, 9.3%; P ¼ 0.87) within the groups. Hospitalization time was shorter in the SDD group (9.5 days 4.6 vs. 10.9 days 5.5; P ¼ 0.007), whereas intraoperative brain expansion was seen more often in the SPD group (19.3%, n ¼ 33 vs. 9.1%, n ¼ 26; P ¼ 0.000; Table 2). Potential Risk Factors for Drain Misplacement in the SDD Group Risk factors associated with drain misplacement in univariate analysis were acute on cSDHs, low preoperative Glasgow Coma Scale (GCS) score, no intraoperative brain expansion, less MLS, smaller hematoma volume on preoperative CT, and longer surgery time. Furthermore, intake of vitamin K antagonists (VKA), acetylsalicylic acid, or different oral anticoagulants (DOACS), as well as longer discontinuation time of blood thinners, were also statistically significant risk factors in the univariate analysis (Table 3). After multivariate analysis, intake of VKA (odds ratio [OR], 3.64; 95% confidence interval [CI], 1.07e12.36; P ¼ 0.039) or DOACS (OR, 10.24; 95% CI, 1.59e65.86; P ¼ 0.014) and low preoperative GCS score (OR, 7.81; 95% CI, 0.94e66.67; P ¼ 0.058) remained strongly associated risk factors with drain misplacement. Clinical Outcome in Patients with Drain Misplacement in the SDD Group Patients with misplaced drains showed a strong association with lower modified Rankin Scale score at release, higher rates of
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Table 1. Baseline Characteristics of the Subdural Drain and Subperiosteal Drain Cohorts Subdural Drain (n [ 290) Sex (female) Age (years), mean SD
Subperiosteal Drain (n [ 171)
P
82 (28.3)
57 (33.3)
0.29
77.7 10.1
77.3 9.9
0.45
155/287 (54.0)
116 (67.8)
0.004
Comorbidities Arterial hypertension
Table 1. Continued
Subacute Hygroma 3
Hematoma volume (mm ), mean SD Midline shift (mm), mean SD
Subdural Drain (n [ 290)
Subperiosteal Drain (n [ 171)
43/279 (15.4)
16/167 (9.6)
6/279 (2.2)
4/167 (2.4)
120.0 72.7
97.2 52.2
0.001
7.2 4.3
6.3 4.1
0.04
P
Blood thinners
Coronary artery disease
56/286 (19.6)
32 (18.7)
0.90
Coronary stent
25/287 (8.7)
4 (2.3)
0.02
Acetylsalicylic acid
66/287 (23.0)
40/171 (23.4)
1
Coronary artery bypass grafting
16/287 (5.6)
5 (2.9)
0.31
Vitamin K antagonists
62/287 (21.6)
36/171 (21.1)
0.91
Clopidogrel
16/287 (5.6)
9/171 (5.3)
1
Direct oral anticoagulants
17/287 (5.9)
13/171 (7.6)
0.56
68.3 27.4
0.08
Diabetes mellitus
40/287 (13.9)
40 (13.9)
0.37
Transitory ischemic attack/cerebral vascular insufficiency
54/287 (18.8)
26 (15.2)
0.45
Peripheral arterial occlusive disease
15/287 (5.2)
6 (3.5)
0.49
Carotid stenosis
5/287 (1.7)
6 (3.5)
0.34
Atrial fibrillation
60/287 (20.9)
41 (24.0)
0.49
Hypercholesterinemia
26/287 (9.1)
23 (13.5)
0.16
Hemophilia
10/287 (3.5)
11 (6.4)
0.17
Liver failure
1/287 (0.3)
2 (1.2)
0.56
Operation time (minutes), mean SD 63e0 26.2
Preoperative symptoms Glasgow Coma Scale score
0.36
15e14
244/284 (85.9) 138/170 (81.2)
13e9
32/284 (11.3)
27/170 (15.9)
8e3
8/284 (2.8)
5/170 (2.9)
Motor deficit
153 (52.8)
74 (43.3)
0.05
16 (5.5)
10 (5.8)
1
Sensory deficit Headaches Gait disturbance Seizures Aphasia
8 (30.3)
51 (29.8)
0.92
112 (38.6)
47 (27.5)
0.02
10 (3.4)
8 (4.7)
0.62
42 (14.5)
29 (17)
0.51
Confusion
60/266 (22.6)
35/157 (22.3)
1
Vertigo
20/266 (7.5)
16/157 (10.2)
0.37
Others
28 (9.7)
23 (13.5)
0.22
146 (50.3)
92 (53.8)
0.5
Hematoma characteristics Side (left) Layering
164/268 (61.2) 102/166 (61.4) 0.52
Hematoma type
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. SD, standard deviation.
postoperative acute epidural or acute subdural hematomas, longer operation and hospitalization times, and more frequent release to another hospital or rehabilitation facilities (Table 4). After multivariate analysis, postoperative bleeding (OR, 5.81; 95% CI, 2.11e16.13; P ¼ 0.001), longer operation time (OR, 1.01; 95% CI, 1.00e1.03; P ¼ 0.028), and hospitalization time (OR, 1.08; 95% CI, 1.01e1.16; P ¼ 0.024) remained significantly associated with drain misplacement. Potential Risk Factors for Postoperative Intracranial Bleedings Not Clearly Associated with Drain Misplacement in the SDD Group Patients with bleeding not clearly caused by drain displacement showed a strong association with hematoma type, drain misplacement, lack of intraoperative brain expansion, age, MLS, surgery time, preoperative GCS score, preoperative thrombocyte level, and intraoperative blood loss. After multivariate analysis, drain misplacement (OR, 2.89; 95% CI, 0.90e9.35; P ¼ 0.076), higher amount of blood loss intraoperatively (OR, 1.01; 95% CI, 0.99e1.01; P ¼ 0.079), and amount of brain expansion (OR, 8.00; 95% CI, 0.70e90.64; P ¼ 0.094) remained associated risk factors for postoperative bleeding not clearly associated with drain misplacement. Compared with SPD, none of the analyzed potential risk factors, except for higher amount of blood loss intraoperatively, was associated with postoperative bleeding not clearly associated with drain misplacement (Table 5).
0.33
Chronic
135/279 (48.4)
82/167 (49.1)
DISCUSSION
Acute on chronic
95/279 (34.1)
65/167 (38.9)
Our study shows a drain misplacement rate of 15.8%, with 6.8% causing iatrogenic bleedings and 12.3% causing neurologic symptoms. All misplaced drains were from the SDD group. Risk factors strongly associated with drain misplacement in
Continues
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Table 2. Outcomes and Complications in the Subdural Drain and Subperiosteal Drain Cohorts Subdural Drain (n [ 290)
Subperiosteal Drain (n [ 171)
P
27 (9.3)
17 (9.9)
0.87
26/287 (9.1)
33 (19.3)
<0.001
Intraoperative blood loss (mL), mean SD
131.3 106.5
118.2 65.5
0.98
Drain misplacement
73/287 (25.4)
0 (0)
<0.001
Recurrence Intraoperative brain expansion
55/72 (76.4)
Within cortex no bleed
12/72 (16.7)
Within cortex with bleed
9/72 (12.5)
Bleed without displacement
28/286 (9.8)
Acute epidural hematoma
3/288 (1)
Acute subdural hematoma
22/288 (7.6)
16 (9.4) 0 (0) 14 (8.2)
1 0.18 0.86
3/288 (1)
3 (1.8)
0.68
Subarachnoid hemorrhage
3/288 (1)
0 (0)
0.30
Revision surgery for bleed
3/31 (9.7)
2/16 (12.5)
1
Postoperative infection
6/285 (2.1)
5/170 (2.9)
0.75
Infection type
Brain abscess
5/6 (83.3)
0
3/5 (60)
0.07
6/6 (100)
4/5 (80)
0.46
16/256 (6.3)
10/149 (6.7)
0.84
Generalized
1/11 (9.1)
2/9 (22.2)
Focal
8/11 (72.7)
7/9 (77.8)
Both
2/11 (18.2)
0
9.5 4.6
10.9 5.5
Postoperative seizures Seizures type
Hospitalization (days), mean SD
0.33
Release destination
0.007 0.28
Home
143/280 (51.1)
81/166 (48.8)
Rehabilitation
65/280 (23.2)
50/166 (30.1)
Other hospital
48/280 (17.1)
20/166 (12.0)
Nursing home
24/280 (8.6)
15/166 (9)
mRS score at release
159/169 (94.1)
4e5
22/285 (7.7)
8/169 (4.7)
6
4/285 (1.4)
2/169 (1.2)
1.5 1.3
1.5 1.2
Glasgow Coma Scale score at release 271/284 (95.4)
160/169 (94.7)
13e9
13/284 (4.6)
8/169 (4.7)
8e3
0
1/169 (0.6)
Mean SD
14.7 0.7
14.7 1
Same
22/284 (7.7)
12/169 (7.1)
Better
259/284 (88)
152/169 (89.9)
Worse
12/284 (4.2)
5/169 (3)
Mortality
7/290 (2.4)
5/171 (2.9)
229/334 (97.9)
140/148 (94.6)
5/334 (2.1)
7/148 (4.7)
0.52 0.93
1.0 3.9
4e5
0.45 Continues
WORLD NEUROSURGERY 138: e426-e436, JUNE 2020
0.869
0.40 0.78
mRS FU
Mean SD
P
0.43
14e15
0.77 0.16
Neurology at FU
0.06 0.92
Same
48/234 (20.5)
29/148 (19.6)
Better
180/234 (76.9)
116/148 (78.4)
Clinical FU (days), mean SD
0
Revision surgery for infection
259/285 (90.9)
Worse
2/5 (40)
1/6 (16.7)
Wound infection
0e3
0e3
Intracerebral hemorrhage
Empyema
Subperiosteal Drain (n [ 171)
Neurology at release
5/72 (6.9)
Symptomatic displacement
Subdural Drain (n [ 290)
Mean SD
Type of misplacement Touching cortex
Table 2. Continued
6/234 (2.6)
3/148 (2)
44.0 42.0
55.1 56.8
0.006
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. SD, standard deviation; mRS, modified Rankin Scale; FU, follow-up.
multivariate analysis were intake of VKA or DOACS and low preoperative GCS score. Once a drain misplacement occurred, a strong association with postoperative bleeding, longer operation time, and hospitalization time was seen. Although not significant on multivariate analysis, a trend for a strong association between drain misplacement and higher amount of blood loss intraoperatively, intraoperative brain expansion, and postoperative bleedings not clearly associated with drain misplacement was seen. Drain Misplacement in Burr-Hole Drainage of cSDH Although rarely described, bleeding complications related to drain misplacement are potentially severe.5 SDDs are positioned between the dura and the cortex, close to the cortical surface, bridging veins, and hematoma membranes. Therefore, the consequences might be devastating, leading to bleeding in the brain parenchyma, causing neurologic deficits, seizures, and
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Table 3. Potential Risk Factors for Drain Misplacement in Univariate Analysis No Drain Misplacement Drain Misplacement (n [ 214) (n [ 73) Odds Ratio (95% Confidence Interval)
P
Sex (female)
56 (26.2)
25 (34.2)
1.5 (0.83e2.60)
0.23
Side (left)
112 (52.3)
40 (54.8)
1.3 (0.78e2.23)
0.34
Layering
129/206 (62.6)
35/62 (56.5)
0.77 (0.44e1.38)
0.46
N/A
<0.001
0.87 (0.41e1.89)
0.85
Hematoma type Chronic
113/210 (53.8)
Acute on chronic
58/210 (27.6)
37 (53.6)
Subacute
36/210 (17.1)
7/69 (10.1)
Hygroma
3/210 (1.4)
3/69 (4.3)
33 (15.4)
10 (13.7)
Dalteparin preoperatively
22 (31.9)
Blood thinners Acetylsalicylic acid
57 (26.6)
9 (12.3)
2.58 (1.21e5.53)
0.02
Vitamin K antagonists
36 (16.8)
26 (35.6)
0.37 (0.20e0.67)
0.002
Clopidogrel
13 (6.1)
3 (4.1)
1.51 (0.42e5.45)
0.77
Different oral anticoagulants
8 (3.7)
9 (12.3)
0.28 (0.10e0.75)
0.02
Hemophilia
8 (3.7)
2 (2.7)
1.38 (0.29e6.65)
1
Liver failure
0
1 (1.4)
1.01 (0.98e1.04)
0.25
N/A
0.001
Comorbidities
Brain expansion intraoperatively No
5 (2.3)
6 (8.2)
Yes
26 (12.1)
0
183 (85.5)
67 (91.8)
Age (years), mean SD
Unknown
77.07 10.7
79.6 8.4
0.07
Midline shift (mm), mean SD
7.54 4.37
6.24 4.0
0.04
Hematoma volume (mm ), mean SD
121.6 52.0
115.6 110.6
0.02
Operation time (minutes), mean SD
59.79 23.90
72.54 30.11
0.001
14.2 1.5
13.6 2.33
0.02
Hemoglobin level preoperatively (g/L), mean SD
129.6 18.9
126.0 14.2
0.07
Thrombocyte level preoperatively (g/L 109), mean SD
227.4 77.8
256.3 99.1
0.08
3
Glasgow Coma Scale score preoperatively (mean SD)
International normalized ratio preoperatively (mean SD) Blood loss (mL), mean SD Blood thinners stop preoperatively (days), mean SD
1.13 0.3
1.13 0.12
0.07
127.9 100.2
138.6 119.5
0.68
1.6 7.6
3.9 10.9
0.002
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. N/A, not available; SD, standard deviation.
even death.6,7 Studies analyzing and describing the occurrence of drain misplacement after burr-hole drainage of cSDH are scarce.3-5 A case report by Pavlov et al.4 showed an intracerebral and intraventricular hemorrhage caused by drain misplacement, although the patient had a full recovery at 2 months. Chan et al.5 described 2 patients with suspected iatrogenic acute
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subdural hematoma after drain removal. Even although these drains were not misplaced, they hypothetically caused bleeding through tearing of membranes or vessels while the drain was removed. The recently reported randomized cSDH-Drain-Trial,3 comparing recurrence rates of surgically drained cSDH after insertion of SDD and SPD, showed a significantly higher drain
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Table 4. Association Between Drain Misplacement and Clinical Outcome in Univariate Analysis
Recurrence
No Drain Displacement (n [ 214)
Drain Displacement (n [ 73)
Odds Ratio (95% Confidence Interval)
20 (9.3)
5 (6.8)
1.4 (0.51e3.88)
0.64
N/A
0.007
N/A
<0.001
2.6 (0.85e8.04)
0.10
N/A
0.009
Release destination Home
117/209 (56)
26/71 (36.6)
Rehabilitation
41/209 (19.6)
24/71 (33.89)
Other hospital
31/209 (14.8)
17/71 (23.9)
Nursing home
20/209 (9.6)
4/71 (5.6)
mRS score at release 0e3
202/212 (95.3)
57 (78.1)
4e5
7/212 (3.3)
15 (20.5)
Glasgow Coma Scale score at release 15e14
204/211 (96.7)
67 (91.8)
13e9
7/211 (3.3)
6 (8.2)
Neurology at release
P
Better
193/211 (91.5)
11 (15.1)
Same
11/211 (5.2)
57 (78.1)
Worse
7/211 (3.3)
5 (6.8)
10 (4.7)
18/72 (25.0)
6.8 (2.9e15.58)
<0.001
Acute epidural hematoma
0
3/72 (4.1)
1.04 (0.99e1.10)
0.02
Acute subdural hematoma
7 (3.3)
15/72 (20.5)
7.65 (2.98e19.64)
<0.001
Intracerebral hemorrhage
2 (0.9)
1/72 (1.4)
1.47 (0.13e16.48)
1
Subarachnoid hemorrhage
2 (0.9)
1/72 (1.4)
1.47 (0.13e16.58)
1
2 (20)
1 (4.8)
0.2 (0.02e2.53)
0.24
5/212 (2.4)
1 (1.4)
0.58 (0.07e5.0)
1
Seizures
10 (5.5)
5 (7.0)
0.77 (0.25e2.33)
0.77
Mortality
6 (2.8)
1 (1.4)
0.48 (0.06e4.01)
0.68
0.83 (0.09e7.59)
1
N/A
0.13
Bleed without displacement
Revision surgery for bleed Postoperative infection
mRS at FU 0e3
176/180 (97.8)
53/54 (98.1)
4e5
4/180 (2.2)
1/54 (1.9)
Better
143/180 (79.4)
14/54 (25.9)
Same
34/180 (18.9)
37/54 (68.5)
Neurology at FU
Worse Operation time (mean SD)
3/180 (1.7)
3/54 (5.6)
59.8 23.9
72.54 30.11
0.001
Hospitalization (days), mean SD
8.9 4.0
11.29 5.77
<0.001
mRS score at release (mean SD)
1.37 1.10
1.90 1.57
0.03
Glasgow Coma Scale at release (mean SD)
14.7 0.62
14.60 0.85
0.62
mRS score at FU (mean SD)
0.43 0.87
0.83 1.04
0.001
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. N/A, not available; mRS, modified Rankin scale, FU, follow-up; SD, standard deviation.
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Table 5. Risk Factors for Bleeds Without Drain Displacement Bleed without Drain Displacement (No) (n [ 258)
Bleed without Brain Displacement (Yes) (n [ 28)
Odds Ratio (95% Confidence Interval)
Sex (female)
72 (27.9)
8 (28.6)
1.03 (0.44e2.45)
1
Layering
96 (39.7)
17 (68)
1.40 (0.58e3.37)
0.52
N/A
0.001
Chronic
127/253 (50.2)
8/25 (32)
Acute on chronic
79/253 (31.2)
15/25 (60)
Hematoma type
P
Subacute
43/253 (17)
0
Hygroma
4/253 (1.6)
2/25 (8)
Dalteparin preoperatively
40 (15.5)
3 (10.7)
0.65 (0.19e2.27)
0.78
Acetylsalicylic acid
61 (23.6)
5 (17.9)
1.42 (0.52e3.91)
0.64
Vitamin K antagonists
55 (21.3)
6 (21.4)
0.99 (0.38e2.57)
1
Clopidogrel
15 (5.8)
1 (3.6)
1.67 (0.21e13.12)
1
Different oral anticoagulants
14 (5.4)
2 (7.1)
0.75 (0.16e3.47)
0.67
10 (3.9)
0
0.96 (0.94e0.99)
0.61
Blood thinners
Comorbidities Hemophilia Liver failure Drain displacement
1 (0.4)
0
1.0 (0.99e1.00)
0.74
54 (20.9)
18 (64.3)
6.8 (3.0e15.58)
0.000
N/A
0.09
0.90 (0.17e4.78)
1
N/A
0.000
Type of displacement touching cortex
38 (70.4)
16 (94.1)
Within cortex, no bleed
12 (22.2)
0
Within cortex, bleed
4 (7.4)
1 (5.9)
Symptomatic misplacement
7/54 (13)
2/17 (11.8)
Brain expansion intraoperatively No
4 (1.6)
6 (21.49)
Yes
24 (9.3)
2 (7.1)
230 (89.1)
20 (71.4)
Age (years), mean SD
82.75 6.8
77.14 4.34
0.001
Midline shift (mm), mean SD
5.04 3.02
7.41 4.34
0.006
Hematoma volume (mm3), mean SD
128.01 96.28
119.05 70.14
0.701
Operation time (minutes), mean SD
75.66 20.18
61.68 26.45
0.001
Glasgow Coma Scale score preoperatively
13.25 2.56
14.16 1.65
0.009
Not documented
0.80 1.03
2.04 8.38
0.32
Hemoglobin level preoperatively (g/L), mean SD
125.07 15.93
129.13 18.06
0.35
Thrombocyte level preoperatively (g/L 109), mean SD
272.96 101.61
230.53 81.72
0.04
International normalized ratio preoperatively (mean SD)
1.14 0.013
1.13 0.30
0.23
Blood loss (mL), mean SD
176.79 134.36
123.28 99.60
0.03
Blood thinners stop preoperatively (days)
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. N/A, not available; SD, standard deviation.
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misplacement rate of 17% for patients with SDD insertion. Similar to our results, in the SPD drain no misplacement and no iatrogenic bleeding occurred. Comparing drain misplacement rates with those found in our prospective randomized trial, similar results were found (15.8% vs. 17%). Interpretation of our data in the context of other studies is difficult, because to our knowledge, only the previously mentioned case report4 and case series5 exist. Some factors might reduce drain misplacement, such as the experience of the surgeon, placing a thread for drain guidance, or creating larger burr holes. However, these techniques still do not provide 100% security and are associated with manipulations within the subdural space; therefore, we recommend avoiding the placement of SDD whenever possible and placing an SPD instead, which seems safer. Potential Risk Factors for Drain Misplacement Our results showed intake of VKA or DOACS, and low preoperative GCS score, to be strongly associated with drain misplacement. Patients with misplaced drain did not show higher intraoperative brain expansion rates than those with no drain misplacement, but rather the opposite. This situation might be because if brain expansion occurs, either the surgeon is more careful when placing an SDD or is reluctant to place one, as shown in a recently reported survey.8 In many patients, the information on intraoperative brain expansion was not available, and therefore, these results might be skewed. Smaller preoperative hematoma volume and less MLS were associated with drain misplacement only on univariate analysis. Hypothetically, the risk of drain misplacement in thinner hematomas is expected to be higher; however, this was not shown in our multivariate analysis. Literature on potential risk factors for drain misplacement does not exist, and therefore, further studies are needed to confirm our findings.
alternative to the insertion of an SDD with comparable recurrence rates, and surgical infection rates and the occurrence of iatrogenic brain injuries are significantly reduced.3 Limitations This retrospective study is subject to all limitations of data collection inherent in such work. Some patients were lost to follow-up; however, at last follow-up, data of 385 patients were available, leading to a follow-up rate of almost 85%. Second, patients were not equally distributed between the drain groups, with 62.6% receiving an SDD and 36.9% receiving an SPD. Although the patients in both collectives were overall well matched, hematoma volumes and MLSs differed, which might have biased the results. However, the SDD group showed larger preoperative hematoma volumes and more MLS than did the SPD group, which should lead to less drain misplacements, as seen in our univariate analysis. Still, the drain misplacement rate was significantly higher in the SDD group and might have been even higher if hematoma volume and MLS distribution between the groups had been similar. Third, because of the retrospective setting of the study, the level of experience among the operating neurosurgeons could not be assessed. However, in most cases, surgery was performed by a team of consultant and resident except for the cases in which the resident was experienced enough. Because in hematomas with smaller volume or more intraoperative brain expansion, patients with antiplatelet or anticoagulation, or in cases of multiple membranes, surgeons might be more reluctant to place an SDD, our results might be biased by these variables.8 This study is to our knowledge the first to primarily analyze the rate of drain misplacement, its potential risk factors, and the outcome after drain misplacement, based on a large cohort within 2 different neurosurgical institutes. CONCLUSIONS
Clinical Outcome in Patients with Drain Misplacement An association between postoperative bleeding, longer operation time, and hospitalization time with misplacement of SDD was seen in our study. This finding raises the question whether SPD should be the preferred drain after burr-hole drainage of cSDH. In addition, once drain misplacement occurred, higher rates of intracranial bleedings, not clearly associated with drain misplacement, were seen. Several investigators have advocated the insertion of SPD, whereby intracranial bleeds, drains placed accidentally within the cortex, or seizures can be averted.6,7,9,10 Most retrospective studies by various groups show no difference in recurrence rates when comparing SPD and SDD insertion after burr-hole drainage of cSDH, whereas some show also lower mortality and fewer serious complications in the SPD group.5,7,9,11-13 The cSDH-Drain-Trial showed in a randomized controlled fashion that the insertion of SPD is an efficient and safe
REFERENCES 1. Weigel R, Schmiedek P, Krauss JK. Outcome of contemporary surgery for chronic subdural haematoma: evidence based review. J Neurol Neurosurg Psychiatry. 2003;74:937-943.
SDD misplacement after burr-hole drainage of cSDH occurs in 15.8% of the cases and seems to lead to more iatrogenic complications, higher intracranial bleeding rates, and longer hospitalization time. Patients treated with VKA or DOACS, as well as patients with lower GCS score at presentation, are potentially at higher risk for SDD misplacement. CRediT AUTHORSHIP CONTRIBUTION STATEMENT Maria Kamenova: Conceptualization, Methodology, Investigation, Writing - original draft. Stefan Wanderer: Methodology, Investigation. Patrick Lipps: Investigation. Serge Marbacher: Writing - review & editing, Supervision, Resources. Luigi Mariani: Writing - review & editing, Supervision, Resources. Jehuda Soleman: Conceptualization, Methodology, Supervision, Writing - review & editing, Project administration.
2. Santarius T, Kirkpatrick PJ, Ganesan D, et al. Use of drains versus no drains after burr-hole evacuation of chronic subdural haematoma: a randomised controlled trial. Lancet. 2009;374:1067-1073.
drainage of chronic subdural hematoma: a randomized clinical trial (cSDH-Drain-Trial). Neurosurgery. 2019;85:E825-E834.
3. Soleman J, Lutz K, Schaedelin S, et al. Subperiosteal vs subdural drain after burr-hole
4. Pavlov V, Bernard G, Chibbaro S. Chronic subdural haematoma management: An iatrogenic
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complication. Case report and literature review. BMJ Case Rep. 2012;2012. pii:bcr1220115397. 5. Chan KW, Datta NN. Iatrogenic acute subdural hematoma due to drainage catheter. Surg Neurol. 2000;54:444-446. 6. Chih ANW, Hieng AWS, Rahman NAA, Abdullah JM. Subperiosteal drainage versus subdural drainage in the management of chronic subdural hematoma (a comparative study). Malays J Med Sci MJMS. 2017;24:21-30. 7. Oral S, Borklu RE, Kucuk A, Ulutabanca H, Selcuklu A. Comparison of subgaleal and subdural closed drainage system in the surgical treatment of chronic subdural hematoma. North Clin Istanb. 2015;2:115-121. 8. Soleman J, Kamenova M, Lutz K, Guzman R, Fandino J, Mariani L. Drain insertion in chronic subdural hematoma: an international survey of practice. World Neurosurg. 2017;104:528-536.
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9. Zumofen D, Regli L, Levivier M, Krayenbühl N. Chronic subdural hematomas treated by burr hole trepanation and a subperiostal drainage system. Neurosurgery. 2009;64:1116-1121 [discussion 1121-1122]. 10. Yadav YR, Parihar V, Chourasia ID, Bajaj J, Namdev H. The role of subgaleal suction drain placement in chronic subdural hematoma evacuation. Asian J Neurosurg. 2016;11:214-218.
13. Zhang JJY, Wang S, Foo ASC, et al. Outcomes of subdural versus subperiosteal drain after burr-hole evacuation of chronic subdural hematoma: a multicenter cohort study. World Neurosurg. 2019; 131:e392-e401. Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
11. Gazzeri R, Galarza M, Neroni M, Canova A, Refice GM, Esposito S. Continuous subgaleal suction drainage for the treatment of chronic subdural haematoma. Acta Neurochir (Wien). 2007; 149:487-493.
Received 14 January 2020; accepted 24 February 2020
12. Bellut D, Woernle CM, Burkhardt J-K, Kockro RA, Bertalanffy H, Krayenbühl N. Subdural drainage versus subperiosteal drainage in burr-hole trepanation for symptomatic chronic subdural hematomas. World Neurosurg. 2012;77:111-118.
Available online: www.sciencedirect.com
Citation: World Neurosurg. (2020) 138:e426-e436. https://doi.org/10.1016/j.wneu.2020.02.166 Journal homepage: www.journals.elsevier.com/worldneurosurgery 1878-8750/$ - see front matter ª 2020 Elsevier Inc. All rights reserved.
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ORIGINAL ARTICLE MARIA KAMENOVA ET AL.
DRAIN MISPLACEMENT AFTER BURR-HOLE DRAINAGE
SUPPLEMENTARY DATA
Supplementary Table 1. Baseline Characteristics of the Whole Cohort All Patients (n [ 463) Sex (female) Age (years), mean SD
All Patients (n [ 463) Acute on chronic
160 (34.6)
140 (30.2)
Subacute
59 (12.7)
77.52 10.0
Hygroma
10 (2.2)
Hematoma volume (mm ), mean SD 3
Comorbidities Arterial hypertension
Supplementary Table 1. Continued
272 (58.7)
110.7 66.1
Midline shift (mm), mean SD
6.9 4.2
Coronary artery disease
88 (19)
Coronary stent
29 (6.3)
Acetylsalicylic acid
106 (22.9)
Coronary artery bypass grafting
21 (4.5)
Vitamin K antagonists
98 (21.2)
Diabetes mellitus
59 (12.7)
Clopidogrel
25 (5.4)
Transitory ischemic attack/cerebral vascular insufficiency
80 (17.3)
Different oral anticoagulants
30 (6.5)
Dalteparin preoperatively
62 (13.4)
Peripheral arterial occlusive disease
21 (4.5)
Carotid stenosis
11 (2.4)
Atrial fibrillation
101 (21.8)
Hypercholesterinemia
49 (10.6)
Hemophilia
21 (4.5)
Liver failure
3 (0.6)
Blood thinners
Drain type Subdural
290 (62.6)
Subperiosteal
171 (36.9)
Recurrence Operation time (minutes), mean SD
44 (9.5) 65.0 26.7
Values are number (%) except where indicated otherwise. N/A, not available; SD, standard deviation.
Preoperative symptoms Glasgow Coma Scale score 15e14
384 (2.9)
13e9
59 (12.7)
8e3
13 (2.8)
Motor deficit
227 (49)
Sensory deficit
26 (5.6)
Headaches
14 (30.5)
Gait disturbance
161 (34.8)
Seizures
18 (3.9)
Aphasia
71 (15.3)
Confusion
95 (20.5)
Vertigo
36 (7.8)
Others
5 (11)
Hematoma characteristics Side (left)
238 (51.4)
Layering
267 (57.7)
Hematoma type Chronic
219 (47.3) Continues
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Supplementary Table 2. Outcome and Complications Rates of the Whole Cohort All Patients (n [ 463)
Supplementary Table 2. Continued All Patients (n [ 463) 8e3
1 (0.2)
Drain misplacement
73 (15.8)
Touching cortex
55 (11.9)
Same
34 (7.3)
Within cortex no bleed
1 (2.6)
Better
404 (87.3)
Within cortex with bleed
5 (6.9)
Worse
17 (3.7)
Symptomatic displacement
9 (12.3)
Mortality
12 (2.6)
Bleed without displacement
44 (9.5)
mRS score at FU
Acute epidural hematoma
3 (0.6)
0e3
371 (80.1)
Acute subdural hematoma
36 (7.8)
4e5
12 (2.6)
Intracerebral hemorrhage
6 (1.3)
Subarachnoid hemorrhage
3 (0.6)
Intraoperative brain expansion Yes
59 (12.7)
Not documented
390 (84.2)
Blood loss (mL), mean SD
126.5 93.7
Revision surgery for bleeding
5 (1.1)
Postoperative infection
11 (2.4)
Neurology at release
Neurology at FU Same
77 (16.6)
Better
298 (64.4)
Worse
9 (1.9)
Clinical FU (days), mean SD
48.2 48.3
Values are number (%) except where indicated otherwise. SD, standard deviation; mRS, modified Rankin Scale; FU, follow-up.
Infection type Empyema
7 (1.5)
Brain abscess
1 (0.2)
Wound infection
3 (0.6)
Revision surgery for infection
10 (2.2)
Postoperative seizures
2 (5.6)
Seizure type Generalized
3 (0.6)
Focal
15 (3.2)
Both
2 (0.4)
Hospitalization (days) (mean SD)
10.06 5.0
Release destination Home
226 (48.8)
Rehabilitation
115 (24.8)
Other hospital
68 (14.7)
Nursing home
39 (8.4)
mRS score at release 0e3
420 (90.7)
4e5
30 (6.5)
Glasgow Coma Scale score at release 15e14
433 (93.5)
13e9
21 (4.5) Continues
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When the Drain Hits the Brain Maria Kamenova1, Stefan Wanderer2, Patrick Lipps3, Serge Marbacher2, Luigi Mariani1,3, Jehuda Soleman1,3
BACKGROUND: The insertion of a subdural drain (SDD) after burr-hole drainage of chronic subdural hematoma (cSDH) was shown to reduce recurrence rate and improve outcome at 6 months. However, studies analyzing the rate of drain misplacement and complications associated with drain misplacement are sparse.
-
METHODS: We analyzed retrospectively a cohort of consecutive patients undergoing burr-hole drainage for cSDH in 2 institutes. Drain type (subperiosteal drain vs. SDD), drain misplacement rate, and drain-associated complications were analyzed. We explored potential risk factors for drain misplacement and associated complications in the SDD subgroup using univariate and multivariate analysis. Drain misplacement was defined as incorrect drain position exceeding the subdural cavity and was categorized into drain misplacement without radiologic sequelae, drain misplacement causing radiologically confirmed iatrogenic bleeding, and drain misplacement causing neurologic symptoms.
-
RESULTS: Of 463 included patients, 290 (62.6%) received an SDD. Drain misplacement occurred in 73 patients (15.8%). In 5 (6.9%) and 9 (12.3%) of these patients, iatrogenic bleeding and neurologic symptoms occurred, respectively. Intake of vitamin K antagonists (odds ratio [OR], 3.64) or different oral anticoagulants (OR, 10.24), and low preoperative Glasgow Coma Scale score (OR, 7.81) remained associated risk factors for drain misplacement
-
Key words Burr-hole drainage - Chronic subdural hematoma - Iatrogenic brain injury - Subdural drain - Surgical technique - Traumatic brain injury -
Abbreviations and Acronyms CI: Confidence interval cSDH: Chronic subdural hematoma CT: Computed tomography DOACS: Different oral anticoagulants GCS: Glasgow Coma Scale MLS: Midline shift OR: Odds ratio
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after multivariate analysis. Patients with misplaced drains showed a strong association with postoperative bleeding (OR, 5.81), longer operation time (OR, 1.01), and hospitalization time (OR, 1.08) after multivariate analysis. CONCLUSIONS: The occurrence of SDD misplacement is unignorable, because it leads to iatrogenic drain-associated complications and seems to affect bleeding events and hospitalization time of patients undergoing burr-hole drainage of cSDH.
-
INTRODUCTION
T
he standard treatment for patients with symptomatic chronic subdural hematomas (cSDHs) is burr-hole drainage and the insertion of a subdural drain (SDD).1 SDD insertion reduces the rate of hematoma recurrence2; however, the consequences of drain misplacement can be devastating.3 Because of the proximity to the brain, the insertion of an SDD is risky and may carry higher perioperative rates of seizures and iatrogenic bleeds.3,4 Studies analyzing the rate of drain misplacement, possible risk factors, and hematoma characteristics associated with a higher rate of drain misplacement are sparse. The aim of this study is to investigate the rate of drain misplacement and its complications, as well as possible factors associated with drain misplacement in a large cohort of patients undergoing burr-hole drainage of symptomatic cSDH.
SDD: Subdural drain SPD: Subperiosteal drain VKA: Vitamin K antagonists From the 1Department of Neurosurgery, University Hospital of Basel, Basel; 2Department of Neurosurgery, Kantonsspital Aarau, Aarau; and 3Faculty of Medicine, University of Basel, Basel, Switzerland To whom correspondence should be addressed: Maria Kamenova M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2020) 138:e426-e436. https://doi.org/10.1016/j.wneu.2020.02.166 Journal homepage: www.journals.elsevier.com/world-neurosurgery Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2020 Elsevier Inc. All rights reserved.
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METHODS We retrospectively included 463 consecutive patients undergoing burr-hole drainage for cSDH between January 2013 and November 2017 at our institutions (245 patients [52.9%] at Kantonsspital Aarau and 218 patients [47.1%] at University Hospital of Basel). The diagnosis of all patients was symptomatic, 1-sided, or bilateral cSDH, confirmed by computed tomography (CT) or magnetic resonance imaging. Hematoma volume was estimated with the formula A B C/2. All patients were treated surgically with burr-hole trepanation (460 patients [99.4%] with 2 burr holes and 3 patients [0.6%] with 1 burr hole), irrigation of the hematoma, and insertion of a passive SDD (n ¼ 290, 62.6%) or subperiosteal drain (SPD) (n ¼ 171, 36.9%). In all cases, a Jackson Pratt drain (a closed drain consisting of an internal drain connected to a grenade-shaped bulb via plastic tube) was inserted for 48 hours. During this period, we kept the patients flat, and the bulb was placed at the level of the head without suction (passive drainage). Patients who presented with an acute subdural hematoma and those who underwent a craniotomy were excluded from the study. Medical records and radiologic studies were reviewed for clinical variables such as age, sex, side of hematoma, hematoma characteristics, comorbidities, concomitant blood thinners, surgery time, length of stay, morbidity, mortality, and outcome. Patients’ characteristics are summarized in Supplementary Table 1. We primarily analyzed the rate of drain misplacement, and drain-associated complications within the whole cohort and then compared these variables between the 2 different drain groups (SDD and SPD). Drain misplacement was defined as incorrect drain position exceeding the subdural cavity and was categorized into drain misplacement without radiologic sequelae, drain misplacement causing radiologically confirmed iatrogenic bleeding, and drain misplacement causing neurologic symptoms. Drain misplacements and associated complications were assessed on the routinely performed CT scan on the first postoperative day, before drain removal. Secondary outcome measures included intracranial bleeding, not clearly associated with drain misplacement, within the 2 groups, possible risk factors (within the SDD group) potentially associated with drain misplacement, the association of drain misplacement with outcome, and potential risk factors for postoperative intracranial bleedings not clearly associated with drain misplacement were analyzed in univariate and logistic regression multivariate analysis. Methods were applied according to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement. The study protocol was approved by the local ethics committee (EKNZ, Basel, Switzerland); because of the retrospective nature of the study, the review board waived the need for informed consent. All statistical analyses were performed using SPSS version 21.0 (IBM Corp., Armonk, New York, USA). Contingency tests were performed using a c2 or Fisher exact test; for nonparametric tests, the Mann-Whitney U test was used. Variables showing P < 0.1 on univariate analysis were included in the logistic regression multivariate analysis. P < 0.05 was considered significant. Methods applied were applied according to the STROBE statement.
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RESULTS Drain Misplacement Rate, Morbidity, Mortality, and Clinical Outcome The overall drain misplacement rate was 15.8% (n ¼ 73); of these, 6.9% (n ¼ 5) caused iatrogenic bleedings and 12.5% (n ¼ 9) caused neurologic symptoms. Of the 3 patients who were treated with a single burr hole, one had an asymptomatic misplaced drain touching the cortex. Mean follow-up time of the whole cohort was 48.20 (48.39) days after surgery. The SPD group had a significantly longer mean follow-up time of 55.05 (56.79) days, compared with the SDD group, with a mean follow-up time of 43.95 (42.05) days (P ¼ 0.006). Follow-up data at the time of hospital discharge were available for 456 patients (98.5%) (285 patients [98.3%] from the SDD group and 169 patients [98.8%] from the SPD group), whereas at the last follow-up for 385 patients (83.2%) follow-up data were available (235 patients [81.0%] from the SDD group and 148 patients [86.5%] from the SPD group). Morbidity, mortality, and clinical outcome of the whole cohort are presented in Supplementary Table 2. When comparing both groups (SDD and SPD), most baseline characteristics were similarly distributed and are presented in Table 1. In the SDD group, significantly more patients had arterial hypertension, whereas in the SPD group, significantly more patients had coronary artery disease. Concerning hematoma characteristics, in the SDD cohort, midline shift (MLS) and hematoma volumes were significantly larger (7.2 mm3 4.3 vs. 6.3 mm3 4.1, P ¼ 0.04 and 120 mm3 72.7 vs. 97.2 mm3 52.2, P ¼ 0.001, respectively). Drain misplacement occurred in 25.4% (n ¼ 73) of the patients from the SDD group, whereas in the SPD group, no drain misplacement was seen (P < 0.001). Recurrence rates were comparable (SPD, 9.9% and SDD, 9.3%; P ¼ 0.87) within the groups. Hospitalization time was shorter in the SDD group (9.5 days 4.6 vs. 10.9 days 5.5; P ¼ 0.007), whereas intraoperative brain expansion was seen more often in the SPD group (19.3%, n ¼ 33 vs. 9.1%, n ¼ 26; P ¼ 0.000; Table 2). Potential Risk Factors for Drain Misplacement in the SDD Group Risk factors associated with drain misplacement in univariate analysis were acute on cSDHs, low preoperative Glasgow Coma Scale (GCS) score, no intraoperative brain expansion, less MLS, smaller hematoma volume on preoperative CT, and longer surgery time. Furthermore, intake of vitamin K antagonists (VKA), acetylsalicylic acid, or different oral anticoagulants (DOACS), as well as longer discontinuation time of blood thinners, were also statistically significant risk factors in the univariate analysis (Table 3). After multivariate analysis, intake of VKA (odds ratio [OR], 3.64; 95% confidence interval [CI], 1.07e12.36; P ¼ 0.039) or DOACS (OR, 10.24; 95% CI, 1.59e65.86; P ¼ 0.014) and low preoperative GCS score (OR, 7.81; 95% CI, 0.94e66.67; P ¼ 0.058) remained strongly associated risk factors with drain misplacement. Clinical Outcome in Patients with Drain Misplacement in the SDD Group Patients with misplaced drains showed a strong association with lower modified Rankin Scale score at release, higher rates of
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Table 1. Baseline Characteristics of the Subdural Drain and Subperiosteal Drain Cohorts Subdural Drain (n [ 290) Sex (female) Age (years), mean SD
Subperiosteal Drain (n [ 171)
P
82 (28.3)
57 (33.3)
0.29
77.7 10.1
77.3 9.9
0.45
155/287 (54.0)
116 (67.8)
0.004
Comorbidities Arterial hypertension
Table 1. Continued
Subacute Hygroma 3
Hematoma volume (mm ), mean SD Midline shift (mm), mean SD
Subdural Drain (n [ 290)
Subperiosteal Drain (n [ 171)
43/279 (15.4)
16/167 (9.6)
6/279 (2.2)
4/167 (2.4)
120.0 72.7
97.2 52.2
0.001
7.2 4.3
6.3 4.1
0.04
P
Blood thinners
Coronary artery disease
56/286 (19.6)
32 (18.7)
0.90
Coronary stent
25/287 (8.7)
4 (2.3)
0.02
Acetylsalicylic acid
66/287 (23.0)
40/171 (23.4)
1
Coronary artery bypass grafting
16/287 (5.6)
5 (2.9)
0.31
Vitamin K antagonists
62/287 (21.6)
36/171 (21.1)
0.91
Clopidogrel
16/287 (5.6)
9/171 (5.3)
1
Direct oral anticoagulants
17/287 (5.9)
13/171 (7.6)
0.56
68.3 27.4
0.08
Diabetes mellitus
40/287 (13.9)
40 (13.9)
0.37
Transitory ischemic attack/cerebral vascular insufficiency
54/287 (18.8)
26 (15.2)
0.45
Peripheral arterial occlusive disease
15/287 (5.2)
6 (3.5)
0.49
Carotid stenosis
5/287 (1.7)
6 (3.5)
0.34
Atrial fibrillation
60/287 (20.9)
41 (24.0)
0.49
Hypercholesterinemia
26/287 (9.1)
23 (13.5)
0.16
Hemophilia
10/287 (3.5)
11 (6.4)
0.17
Liver failure
1/287 (0.3)
2 (1.2)
0.56
Operation time (minutes), mean SD 63e0 26.2
Preoperative symptoms Glasgow Coma Scale score
0.36
15e14
244/284 (85.9) 138/170 (81.2)
13e9
32/284 (11.3)
27/170 (15.9)
8e3
8/284 (2.8)
5/170 (2.9)
Motor deficit
153 (52.8)
74 (43.3)
0.05
16 (5.5)
10 (5.8)
1
Sensory deficit Headaches Gait disturbance Seizures Aphasia
8 (30.3)
51 (29.8)
0.92
112 (38.6)
47 (27.5)
0.02
10 (3.4)
8 (4.7)
0.62
42 (14.5)
29 (17)
0.51
Confusion
60/266 (22.6)
35/157 (22.3)
1
Vertigo
20/266 (7.5)
16/157 (10.2)
0.37
Others
28 (9.7)
23 (13.5)
0.22
146 (50.3)
92 (53.8)
0.5
Hematoma characteristics Side (left) Layering
164/268 (61.2) 102/166 (61.4) 0.52
Hematoma type
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. SD, standard deviation.
postoperative acute epidural or acute subdural hematomas, longer operation and hospitalization times, and more frequent release to another hospital or rehabilitation facilities (Table 4). After multivariate analysis, postoperative bleeding (OR, 5.81; 95% CI, 2.11e16.13; P ¼ 0.001), longer operation time (OR, 1.01; 95% CI, 1.00e1.03; P ¼ 0.028), and hospitalization time (OR, 1.08; 95% CI, 1.01e1.16; P ¼ 0.024) remained significantly associated with drain misplacement. Potential Risk Factors for Postoperative Intracranial Bleedings Not Clearly Associated with Drain Misplacement in the SDD Group Patients with bleeding not clearly caused by drain displacement showed a strong association with hematoma type, drain misplacement, lack of intraoperative brain expansion, age, MLS, surgery time, preoperative GCS score, preoperative thrombocyte level, and intraoperative blood loss. After multivariate analysis, drain misplacement (OR, 2.89; 95% CI, 0.90e9.35; P ¼ 0.076), higher amount of blood loss intraoperatively (OR, 1.01; 95% CI, 0.99e1.01; P ¼ 0.079), and amount of brain expansion (OR, 8.00; 95% CI, 0.70e90.64; P ¼ 0.094) remained associated risk factors for postoperative bleeding not clearly associated with drain misplacement. Compared with SPD, none of the analyzed potential risk factors, except for higher amount of blood loss intraoperatively, was associated with postoperative bleeding not clearly associated with drain misplacement (Table 5).
0.33
Chronic
135/279 (48.4)
82/167 (49.1)
DISCUSSION
Acute on chronic
95/279 (34.1)
65/167 (38.9)
Our study shows a drain misplacement rate of 15.8%, with 6.8% causing iatrogenic bleedings and 12.3% causing neurologic symptoms. All misplaced drains were from the SDD group. Risk factors strongly associated with drain misplacement in
Continues
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Table 2. Outcomes and Complications in the Subdural Drain and Subperiosteal Drain Cohorts Subdural Drain (n [ 290)
Subperiosteal Drain (n [ 171)
P
27 (9.3)
17 (9.9)
0.87
26/287 (9.1)
33 (19.3)
<0.001
Intraoperative blood loss (mL), mean SD
131.3 106.5
118.2 65.5
0.98
Drain misplacement
73/287 (25.4)
0 (0)
<0.001
Recurrence Intraoperative brain expansion
55/72 (76.4)
Within cortex no bleed
12/72 (16.7)
Within cortex with bleed
9/72 (12.5)
Bleed without displacement
28/286 (9.8)
Acute epidural hematoma
3/288 (1)
Acute subdural hematoma
22/288 (7.6)
16 (9.4) 0 (0) 14 (8.2)
1 0.18 0.86
3/288 (1)
3 (1.8)
0.68
Subarachnoid hemorrhage
3/288 (1)
0 (0)
0.30
Revision surgery for bleed
3/31 (9.7)
2/16 (12.5)
1
Postoperative infection
6/285 (2.1)
5/170 (2.9)
0.75
Infection type
Brain abscess
5/6 (83.3)
0
3/5 (60)
0.07
6/6 (100)
4/5 (80)
0.46
16/256 (6.3)
10/149 (6.7)
0.84
Generalized
1/11 (9.1)
2/9 (22.2)
Focal
8/11 (72.7)
7/9 (77.8)
Both
2/11 (18.2)
0
9.5 4.6
10.9 5.5
Postoperative seizures Seizures type
Hospitalization (days), mean SD
0.33
Release destination
0.007 0.28
Home
143/280 (51.1)
81/166 (48.8)
Rehabilitation
65/280 (23.2)
50/166 (30.1)
Other hospital
48/280 (17.1)
20/166 (12.0)
Nursing home
24/280 (8.6)
15/166 (9)
mRS score at release
159/169 (94.1)
4e5
22/285 (7.7)
8/169 (4.7)
6
4/285 (1.4)
2/169 (1.2)
1.5 1.3
1.5 1.2
Glasgow Coma Scale score at release 271/284 (95.4)
160/169 (94.7)
13e9
13/284 (4.6)
8/169 (4.7)
8e3
0
1/169 (0.6)
Mean SD
14.7 0.7
14.7 1
Same
22/284 (7.7)
12/169 (7.1)
Better
259/284 (88)
152/169 (89.9)
Worse
12/284 (4.2)
5/169 (3)
Mortality
7/290 (2.4)
5/171 (2.9)
229/334 (97.9)
140/148 (94.6)
5/334 (2.1)
7/148 (4.7)
0.52 0.93
1.0 3.9
4e5
0.45 Continues
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0.869
0.40 0.78
mRS FU
Mean SD
P
0.43
14e15
0.77 0.16
Neurology at FU
0.06 0.92
Same
48/234 (20.5)
29/148 (19.6)
Better
180/234 (76.9)
116/148 (78.4)
Clinical FU (days), mean SD
0
Revision surgery for infection
259/285 (90.9)
Worse
2/5 (40)
1/6 (16.7)
Wound infection
0e3
0e3
Intracerebral hemorrhage
Empyema
Subperiosteal Drain (n [ 171)
Neurology at release
5/72 (6.9)
Symptomatic displacement
Subdural Drain (n [ 290)
Mean SD
Type of misplacement Touching cortex
Table 2. Continued
6/234 (2.6)
3/148 (2)
44.0 42.0
55.1 56.8
0.006
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. SD, standard deviation; mRS, modified Rankin Scale; FU, follow-up.
multivariate analysis were intake of VKA or DOACS and low preoperative GCS score. Once a drain misplacement occurred, a strong association with postoperative bleeding, longer operation time, and hospitalization time was seen. Although not significant on multivariate analysis, a trend for a strong association between drain misplacement and higher amount of blood loss intraoperatively, intraoperative brain expansion, and postoperative bleedings not clearly associated with drain misplacement was seen. Drain Misplacement in Burr-Hole Drainage of cSDH Although rarely described, bleeding complications related to drain misplacement are potentially severe.5 SDDs are positioned between the dura and the cortex, close to the cortical surface, bridging veins, and hematoma membranes. Therefore, the consequences might be devastating, leading to bleeding in the brain parenchyma, causing neurologic deficits, seizures, and
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Table 3. Potential Risk Factors for Drain Misplacement in Univariate Analysis No Drain Misplacement Drain Misplacement (n [ 214) (n [ 73) Odds Ratio (95% Confidence Interval)
P
Sex (female)
56 (26.2)
25 (34.2)
1.5 (0.83e2.60)
0.23
Side (left)
112 (52.3)
40 (54.8)
1.3 (0.78e2.23)
0.34
Layering
129/206 (62.6)
35/62 (56.5)
0.77 (0.44e1.38)
0.46
N/A
<0.001
0.87 (0.41e1.89)
0.85
Hematoma type Chronic
113/210 (53.8)
Acute on chronic
58/210 (27.6)
37 (53.6)
Subacute
36/210 (17.1)
7/69 (10.1)
Hygroma
3/210 (1.4)
3/69 (4.3)
33 (15.4)
10 (13.7)
Dalteparin preoperatively
22 (31.9)
Blood thinners Acetylsalicylic acid
57 (26.6)
9 (12.3)
2.58 (1.21e5.53)
0.02
Vitamin K antagonists
36 (16.8)
26 (35.6)
0.37 (0.20e0.67)
0.002
Clopidogrel
13 (6.1)
3 (4.1)
1.51 (0.42e5.45)
0.77
Different oral anticoagulants
8 (3.7)
9 (12.3)
0.28 (0.10e0.75)
0.02
Hemophilia
8 (3.7)
2 (2.7)
1.38 (0.29e6.65)
1
Liver failure
0
1 (1.4)
1.01 (0.98e1.04)
0.25
N/A
0.001
Comorbidities
Brain expansion intraoperatively No
5 (2.3)
6 (8.2)
Yes
26 (12.1)
0
183 (85.5)
67 (91.8)
Age (years), mean SD
Unknown
77.07 10.7
79.6 8.4
0.07
Midline shift (mm), mean SD
7.54 4.37
6.24 4.0
0.04
Hematoma volume (mm ), mean SD
121.6 52.0
115.6 110.6
0.02
Operation time (minutes), mean SD
59.79 23.90
72.54 30.11
0.001
14.2 1.5
13.6 2.33
0.02
Hemoglobin level preoperatively (g/L), mean SD
129.6 18.9
126.0 14.2
0.07
Thrombocyte level preoperatively (g/L 109), mean SD
227.4 77.8
256.3 99.1
0.08
3
Glasgow Coma Scale score preoperatively (mean SD)
International normalized ratio preoperatively (mean SD) Blood loss (mL), mean SD Blood thinners stop preoperatively (days), mean SD
1.13 0.3
1.13 0.12
0.07
127.9 100.2
138.6 119.5
0.68
1.6 7.6
3.9 10.9
0.002
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. N/A, not available; SD, standard deviation.
even death.6,7 Studies analyzing and describing the occurrence of drain misplacement after burr-hole drainage of cSDH are scarce.3-5 A case report by Pavlov et al.4 showed an intracerebral and intraventricular hemorrhage caused by drain misplacement, although the patient had a full recovery at 2 months. Chan et al.5 described 2 patients with suspected iatrogenic acute
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subdural hematoma after drain removal. Even although these drains were not misplaced, they hypothetically caused bleeding through tearing of membranes or vessels while the drain was removed. The recently reported randomized cSDH-Drain-Trial,3 comparing recurrence rates of surgically drained cSDH after insertion of SDD and SPD, showed a significantly higher drain
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Table 4. Association Between Drain Misplacement and Clinical Outcome in Univariate Analysis
Recurrence
No Drain Displacement (n [ 214)
Drain Displacement (n [ 73)
Odds Ratio (95% Confidence Interval)
20 (9.3)
5 (6.8)
1.4 (0.51e3.88)
0.64
N/A
0.007
N/A
<0.001
2.6 (0.85e8.04)
0.10
N/A
0.009
Release destination Home
117/209 (56)
26/71 (36.6)
Rehabilitation
41/209 (19.6)
24/71 (33.89)
Other hospital
31/209 (14.8)
17/71 (23.9)
Nursing home
20/209 (9.6)
4/71 (5.6)
mRS score at release 0e3
202/212 (95.3)
57 (78.1)
4e5
7/212 (3.3)
15 (20.5)
Glasgow Coma Scale score at release 15e14
204/211 (96.7)
67 (91.8)
13e9
7/211 (3.3)
6 (8.2)
Neurology at release
P
Better
193/211 (91.5)
11 (15.1)
Same
11/211 (5.2)
57 (78.1)
Worse
7/211 (3.3)
5 (6.8)
10 (4.7)
18/72 (25.0)
6.8 (2.9e15.58)
<0.001
Acute epidural hematoma
0
3/72 (4.1)
1.04 (0.99e1.10)
0.02
Acute subdural hematoma
7 (3.3)
15/72 (20.5)
7.65 (2.98e19.64)
<0.001
Intracerebral hemorrhage
2 (0.9)
1/72 (1.4)
1.47 (0.13e16.48)
1
Subarachnoid hemorrhage
2 (0.9)
1/72 (1.4)
1.47 (0.13e16.58)
1
2 (20)
1 (4.8)
0.2 (0.02e2.53)
0.24
5/212 (2.4)
1 (1.4)
0.58 (0.07e5.0)
1
Seizures
10 (5.5)
5 (7.0)
0.77 (0.25e2.33)
0.77
Mortality
6 (2.8)
1 (1.4)
0.48 (0.06e4.01)
0.68
0.83 (0.09e7.59)
1
N/A
0.13
Bleed without displacement
Revision surgery for bleed Postoperative infection
mRS at FU 0e3
176/180 (97.8)
53/54 (98.1)
4e5
4/180 (2.2)
1/54 (1.9)
Better
143/180 (79.4)
14/54 (25.9)
Same
34/180 (18.9)
37/54 (68.5)
Neurology at FU
Worse Operation time (mean SD)
3/180 (1.7)
3/54 (5.6)
59.8 23.9
72.54 30.11
0.001
Hospitalization (days), mean SD
8.9 4.0
11.29 5.77
<0.001
mRS score at release (mean SD)
1.37 1.10
1.90 1.57
0.03
Glasgow Coma Scale at release (mean SD)
14.7 0.62
14.60 0.85
0.62
mRS score at FU (mean SD)
0.43 0.87
0.83 1.04
0.001
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. N/A, not available; mRS, modified Rankin scale, FU, follow-up; SD, standard deviation.
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Table 5. Risk Factors for Bleeds Without Drain Displacement Bleed without Drain Displacement (No) (n [ 258)
Bleed without Brain Displacement (Yes) (n [ 28)
Odds Ratio (95% Confidence Interval)
Sex (female)
72 (27.9)
8 (28.6)
1.03 (0.44e2.45)
1
Layering
96 (39.7)
17 (68)
1.40 (0.58e3.37)
0.52
N/A
0.001
Chronic
127/253 (50.2)
8/25 (32)
Acute on chronic
79/253 (31.2)
15/25 (60)
Hematoma type
P
Subacute
43/253 (17)
0
Hygroma
4/253 (1.6)
2/25 (8)
Dalteparin preoperatively
40 (15.5)
3 (10.7)
0.65 (0.19e2.27)
0.78
Acetylsalicylic acid
61 (23.6)
5 (17.9)
1.42 (0.52e3.91)
0.64
Vitamin K antagonists
55 (21.3)
6 (21.4)
0.99 (0.38e2.57)
1
Clopidogrel
15 (5.8)
1 (3.6)
1.67 (0.21e13.12)
1
Different oral anticoagulants
14 (5.4)
2 (7.1)
0.75 (0.16e3.47)
0.67
10 (3.9)
0
0.96 (0.94e0.99)
0.61
Blood thinners
Comorbidities Hemophilia Liver failure Drain displacement
1 (0.4)
0
1.0 (0.99e1.00)
0.74
54 (20.9)
18 (64.3)
6.8 (3.0e15.58)
0.000
N/A
0.09
0.90 (0.17e4.78)
1
N/A
0.000
Type of displacement touching cortex
38 (70.4)
16 (94.1)
Within cortex, no bleed
12 (22.2)
0
Within cortex, bleed
4 (7.4)
1 (5.9)
Symptomatic misplacement
7/54 (13)
2/17 (11.8)
Brain expansion intraoperatively No
4 (1.6)
6 (21.49)
Yes
24 (9.3)
2 (7.1)
230 (89.1)
20 (71.4)
Age (years), mean SD
82.75 6.8
77.14 4.34
0.001
Midline shift (mm), mean SD
5.04 3.02
7.41 4.34
0.006
Hematoma volume (mm3), mean SD
128.01 96.28
119.05 70.14
0.701
Operation time (minutes), mean SD
75.66 20.18
61.68 26.45
0.001
Glasgow Coma Scale score preoperatively
13.25 2.56
14.16 1.65
0.009
Not documented
0.80 1.03
2.04 8.38
0.32
Hemoglobin level preoperatively (g/L), mean SD
125.07 15.93
129.13 18.06
0.35
Thrombocyte level preoperatively (g/L 109), mean SD
272.96 101.61
230.53 81.72
0.04
International normalized ratio preoperatively (mean SD)
1.14 0.013
1.13 0.30
0.23
Blood loss (mL), mean SD
176.79 134.36
123.28 99.60
0.03
Blood thinners stop preoperatively (days)
Values are number (%) except where indicated otherwise. Values in bold type indicate significance at P < 0.05. N/A, not available; SD, standard deviation.
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misplacement rate of 17% for patients with SDD insertion. Similar to our results, in the SPD drain no misplacement and no iatrogenic bleeding occurred. Comparing drain misplacement rates with those found in our prospective randomized trial, similar results were found (15.8% vs. 17%). Interpretation of our data in the context of other studies is difficult, because to our knowledge, only the previously mentioned case report4 and case series5 exist. Some factors might reduce drain misplacement, such as the experience of the surgeon, placing a thread for drain guidance, or creating larger burr holes. However, these techniques still do not provide 100% security and are associated with manipulations within the subdural space; therefore, we recommend avoiding the placement of SDD whenever possible and placing an SPD instead, which seems safer. Potential Risk Factors for Drain Misplacement Our results showed intake of VKA or DOACS, and low preoperative GCS score, to be strongly associated with drain misplacement. Patients with misplaced drain did not show higher intraoperative brain expansion rates than those with no drain misplacement, but rather the opposite. This situation might be because if brain expansion occurs, either the surgeon is more careful when placing an SDD or is reluctant to place one, as shown in a recently reported survey.8 In many patients, the information on intraoperative brain expansion was not available, and therefore, these results might be skewed. Smaller preoperative hematoma volume and less MLS were associated with drain misplacement only on univariate analysis. Hypothetically, the risk of drain misplacement in thinner hematomas is expected to be higher; however, this was not shown in our multivariate analysis. Literature on potential risk factors for drain misplacement does not exist, and therefore, further studies are needed to confirm our findings.
alternative to the insertion of an SDD with comparable recurrence rates, and surgical infection rates and the occurrence of iatrogenic brain injuries are significantly reduced.3 Limitations This retrospective study is subject to all limitations of data collection inherent in such work. Some patients were lost to follow-up; however, at last follow-up, data of 385 patients were available, leading to a follow-up rate of almost 85%. Second, patients were not equally distributed between the drain groups, with 62.6% receiving an SDD and 36.9% receiving an SPD. Although the patients in both collectives were overall well matched, hematoma volumes and MLSs differed, which might have biased the results. However, the SDD group showed larger preoperative hematoma volumes and more MLS than did the SPD group, which should lead to less drain misplacements, as seen in our univariate analysis. Still, the drain misplacement rate was significantly higher in the SDD group and might have been even higher if hematoma volume and MLS distribution between the groups had been similar. Third, because of the retrospective setting of the study, the level of experience among the operating neurosurgeons could not be assessed. However, in most cases, surgery was performed by a team of consultant and resident except for the cases in which the resident was experienced enough. Because in hematomas with smaller volume or more intraoperative brain expansion, patients with antiplatelet or anticoagulation, or in cases of multiple membranes, surgeons might be more reluctant to place an SDD, our results might be biased by these variables.8 This study is to our knowledge the first to primarily analyze the rate of drain misplacement, its potential risk factors, and the outcome after drain misplacement, based on a large cohort within 2 different neurosurgical institutes. CONCLUSIONS
Clinical Outcome in Patients with Drain Misplacement An association between postoperative bleeding, longer operation time, and hospitalization time with misplacement of SDD was seen in our study. This finding raises the question whether SPD should be the preferred drain after burr-hole drainage of cSDH. In addition, once drain misplacement occurred, higher rates of intracranial bleedings, not clearly associated with drain misplacement, were seen. Several investigators have advocated the insertion of SPD, whereby intracranial bleeds, drains placed accidentally within the cortex, or seizures can be averted.6,7,9,10 Most retrospective studies by various groups show no difference in recurrence rates when comparing SPD and SDD insertion after burr-hole drainage of cSDH, whereas some show also lower mortality and fewer serious complications in the SPD group.5,7,9,11-13 The cSDH-Drain-Trial showed in a randomized controlled fashion that the insertion of SPD is an efficient and safe
REFERENCES 1. Weigel R, Schmiedek P, Krauss JK. Outcome of contemporary surgery for chronic subdural haematoma: evidence based review. J Neurol Neurosurg Psychiatry. 2003;74:937-943.
SDD misplacement after burr-hole drainage of cSDH occurs in 15.8% of the cases and seems to lead to more iatrogenic complications, higher intracranial bleeding rates, and longer hospitalization time. Patients treated with VKA or DOACS, as well as patients with lower GCS score at presentation, are potentially at higher risk for SDD misplacement. CRediT AUTHORSHIP CONTRIBUTION STATEMENT Maria Kamenova: Conceptualization, Methodology, Investigation, Writing - original draft. Stefan Wanderer: Methodology, Investigation. Patrick Lipps: Investigation. Serge Marbacher: Writing - review & editing, Supervision, Resources. Luigi Mariani: Writing - review & editing, Supervision, Resources. Jehuda Soleman: Conceptualization, Methodology, Supervision, Writing - review & editing, Project administration.
2. Santarius T, Kirkpatrick PJ, Ganesan D, et al. Use of drains versus no drains after burr-hole evacuation of chronic subdural haematoma: a randomised controlled trial. Lancet. 2009;374:1067-1073.
drainage of chronic subdural hematoma: a randomized clinical trial (cSDH-Drain-Trial). Neurosurgery. 2019;85:E825-E834.
3. Soleman J, Lutz K, Schaedelin S, et al. Subperiosteal vs subdural drain after burr-hole
4. Pavlov V, Bernard G, Chibbaro S. Chronic subdural haematoma management: An iatrogenic
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complication. Case report and literature review. BMJ Case Rep. 2012;2012. pii:bcr1220115397. 5. Chan KW, Datta NN. Iatrogenic acute subdural hematoma due to drainage catheter. Surg Neurol. 2000;54:444-446. 6. Chih ANW, Hieng AWS, Rahman NAA, Abdullah JM. Subperiosteal drainage versus subdural drainage in the management of chronic subdural hematoma (a comparative study). Malays J Med Sci MJMS. 2017;24:21-30. 7. Oral S, Borklu RE, Kucuk A, Ulutabanca H, Selcuklu A. Comparison of subgaleal and subdural closed drainage system in the surgical treatment of chronic subdural hematoma. North Clin Istanb. 2015;2:115-121. 8. Soleman J, Kamenova M, Lutz K, Guzman R, Fandino J, Mariani L. Drain insertion in chronic subdural hematoma: an international survey of practice. World Neurosurg. 2017;104:528-536.
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9. Zumofen D, Regli L, Levivier M, Krayenbühl N. Chronic subdural hematomas treated by burr hole trepanation and a subperiostal drainage system. Neurosurgery. 2009;64:1116-1121 [discussion 1121-1122]. 10. Yadav YR, Parihar V, Chourasia ID, Bajaj J, Namdev H. The role of subgaleal suction drain placement in chronic subdural hematoma evacuation. Asian J Neurosurg. 2016;11:214-218.
13. Zhang JJY, Wang S, Foo ASC, et al. Outcomes of subdural versus subperiosteal drain after burr-hole evacuation of chronic subdural hematoma: a multicenter cohort study. World Neurosurg. 2019; 131:e392-e401. Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
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Received 14 January 2020; accepted 24 February 2020
12. Bellut D, Woernle CM, Burkhardt J-K, Kockro RA, Bertalanffy H, Krayenbühl N. Subdural drainage versus subperiosteal drainage in burr-hole trepanation for symptomatic chronic subdural hematomas. World Neurosurg. 2012;77:111-118.
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Citation: World Neurosurg. (2020) 138:e426-e436. https://doi.org/10.1016/j.wneu.2020.02.166 Journal homepage: www.journals.elsevier.com/worldneurosurgery 1878-8750/$ - see front matter ª 2020 Elsevier Inc. All rights reserved.
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DRAIN MISPLACEMENT AFTER BURR-HOLE DRAINAGE
SUPPLEMENTARY DATA
Supplementary Table 1. Baseline Characteristics of the Whole Cohort All Patients (n [ 463) Sex (female) Age (years), mean SD
All Patients (n [ 463) Acute on chronic
160 (34.6)
140 (30.2)
Subacute
59 (12.7)
77.52 10.0
Hygroma
10 (2.2)
Hematoma volume (mm ), mean SD 3
Comorbidities Arterial hypertension
Supplementary Table 1. Continued
272 (58.7)
110.7 66.1
Midline shift (mm), mean SD
6.9 4.2
Coronary artery disease
88 (19)
Coronary stent
29 (6.3)
Acetylsalicylic acid
106 (22.9)
Coronary artery bypass grafting
21 (4.5)
Vitamin K antagonists
98 (21.2)
Diabetes mellitus
59 (12.7)
Clopidogrel
25 (5.4)
Transitory ischemic attack/cerebral vascular insufficiency
80 (17.3)
Different oral anticoagulants
30 (6.5)
Dalteparin preoperatively
62 (13.4)
Peripheral arterial occlusive disease
21 (4.5)
Carotid stenosis
11 (2.4)
Atrial fibrillation
101 (21.8)
Hypercholesterinemia
49 (10.6)
Hemophilia
21 (4.5)
Liver failure
3 (0.6)
Blood thinners
Drain type Subdural
290 (62.6)
Subperiosteal
171 (36.9)
Recurrence Operation time (minutes), mean SD
44 (9.5) 65.0 26.7
Values are number (%) except where indicated otherwise. N/A, not available; SD, standard deviation.
Preoperative symptoms Glasgow Coma Scale score 15e14
384 (2.9)
13e9
59 (12.7)
8e3
13 (2.8)
Motor deficit
227 (49)
Sensory deficit
26 (5.6)
Headaches
14 (30.5)
Gait disturbance
161 (34.8)
Seizures
18 (3.9)
Aphasia
71 (15.3)
Confusion
95 (20.5)
Vertigo
36 (7.8)
Others
5 (11)
Hematoma characteristics Side (left)
238 (51.4)
Layering
267 (57.7)
Hematoma type Chronic
219 (47.3) Continues
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DRAIN MISPLACEMENT AFTER BURR-HOLE DRAINAGE
Supplementary Table 2. Outcome and Complications Rates of the Whole Cohort All Patients (n [ 463)
Supplementary Table 2. Continued All Patients (n [ 463) 8e3
1 (0.2)
Drain misplacement
73 (15.8)
Touching cortex
55 (11.9)
Same
34 (7.3)
Within cortex no bleed
1 (2.6)
Better
404 (87.3)
Within cortex with bleed
5 (6.9)
Worse
17 (3.7)
Symptomatic displacement
9 (12.3)
Mortality
12 (2.6)
Bleed without displacement
44 (9.5)
mRS score at FU
Acute epidural hematoma
3 (0.6)
0e3
371 (80.1)
Acute subdural hematoma
36 (7.8)
4e5
12 (2.6)
Intracerebral hemorrhage
6 (1.3)
Subarachnoid hemorrhage
3 (0.6)
Intraoperative brain expansion Yes
59 (12.7)
Not documented
390 (84.2)
Blood loss (mL), mean SD
126.5 93.7
Revision surgery for bleeding
5 (1.1)
Postoperative infection
11 (2.4)
Neurology at release
Neurology at FU Same
77 (16.6)
Better
298 (64.4)
Worse
9 (1.9)
Clinical FU (days), mean SD
48.2 48.3
Values are number (%) except where indicated otherwise. SD, standard deviation; mRS, modified Rankin Scale; FU, follow-up.
Infection type Empyema
7 (1.5)
Brain abscess
1 (0.2)
Wound infection
3 (0.6)
Revision surgery for infection
10 (2.2)
Postoperative seizures
2 (5.6)
Seizure type Generalized
3 (0.6)
Focal
15 (3.2)
Both
2 (0.4)
Hospitalization (days) (mean SD)
10.06 5.0
Release destination Home
226 (48.8)
Rehabilitation
115 (24.8)
Other hospital
68 (14.7)
Nursing home
39 (8.4)
mRS score at release 0e3
420 (90.7)
4e5
30 (6.5)
Glasgow Coma Scale score at release 15e14
433 (93.5)
13e9
21 (4.5) Continues
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