Original Article
Perioperative management and complications in patients with obstructive sleep apnea undergoing transsphenoidal surgery: Our institutional experience Eiman Rahimi, Ramamani Mariappan, Suresh Tharmaradinam, Pirjo Manninen, Lashmi Venkatraghavan Department of Anesthesia, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
Abstract Background and Aims: Patients with endocrine diseases such as acromegaly and Cushing’s disease have a high prevalence of obstructive sleep apnea (OSA). There is controversy regarding the use of continuous positive airway pressure (CPAP) following transsphenoidal surgery. The aim of this study was to compare the perioperative management and complications, in patients with or without OSA undergoing transsphenoidal surgery. Materials and Methods: After Research Ethics Board approval, we retrospectively reviewed the charts of all patients who underwent transsphenoidal surgery in our institution from 2006 to 2011. Information collected included patients’ demographics, pathology of lesion, history of OSA, anesthetic and perioperative management and incidence of perioperative complications. Patients with sleep study proven OSA were compared with a control group, matched for age, sex and pathology of patients without OSA. Statistical analysis was performed using t-test and Chi-square test and the P < 0.05 was considered to be significant. Results: Out of a total 469 patients undergoing transsphenoidal surgery, 105 patients were found to be at risk for OSA by a positive STOP-BANG scoring assessment. Preoperative sleep study testing was positive for OSA in 38 patients. Post-operative hypoxemia (SpO2 < 90) occurred in 10 (26%) patients with OSA and was treated with high-flow oxygen through face mask (n = 7) and by CPAP mask (n = 3). In the OSA-negative group, 2 patients had hypoxemia and were treated with low-flow oxygen using face mask. There were no differences between the groups with respect to post-operative opioid use, destination, hospital stay or other complications. Conclusions: Post-operative hypoxemia in patients with OSA following transsphenoidal surgery can be treated in most but not all patients with high flow oxygen using the face mask. We were able to safely use CPAP in a very small number of patients but caution is needed to prevent complications. Further prospective studies are needed to determine the safe use of CPAP in patients after transsphenoidal surgery. Key words: Continuous positive airway pressure, obstructive sleep apnea, transsphenoidal surgery
Introduction Obstructive sleep apnea (OSA) is a common sleep related breathing disorder with prevalence between 2 and 25% in the Address for correspondence: Dr. Lashmi Venkatraghavan, Department of Anesthesia, Toronto Western Hospital, University Health Network, University of Toronto, 399 Bathurst Street, Toronto, Ontario, M5T 2S8 Canada. E-mail: [email protected] Access this article online Quick Response Code:
Website: www.joacp.org
DOI: 10.4103/0970-9185.137266
general population.[1] The incidence of OSA in patients with pituitary disease has been reported to be 60-80% in patients with acromegaly and 18-32% with Cushing’s disease.[2-4] The main surgical approach for pituitary surgery is transsphenoidal surgery. There is an increased incidence of perioperative complications among patients with OSA undergoing surgery under general anesthesia.[5] The American Society of Anesthesiologist practice guidelines for the perioperative management of patients with OSA recommends, the use of continuous positive airway pressure (CPAP) or non-invasive positive pressure ventilation with or without supplemental oxygen during the post-operative period in patients who were using these modalities pre-operatively, unless contraindicated by the surgical procedure.[6] The application of CPAP has generally been thought to be contraindicated after transsphenoidal surgery.[7] Complications from the use of CPAP include pneumocephalus especially in the presence of
Journal of Anaesthesiology Clinical Pharmacology | July-September 2014 | Vol 30 | Issue 3
351
Rahimi, et al.: Sleep apnea and transsphenoidal surgery
a cerebrospinal fluid (CSF) leak.[8,9] Currently, there are no relevant guidelines or consensus existing for the management of OSA in patients undergoing transsphenoidal surgery.[10] The aim of this study was to compare the perioperative management and complications, in patients with or without OSA undergoing transsphenoidal surgery in our institution.
Among these, 358 patients had pituitar y pathology consisting of acromegaly (53), Cushing’s disease (54), prolactinomas (41), craniopharyngioma (34), non-secretory macroadenoma (170) and other pituitary lesions (6). The transsphenoidal approach was used for excision of skull base pathology in 111 patients.
Materials and Methods
With the use of the STOP-BANG scoring scale, 105 (22%) patients were identified as high risk for OSA. Of these, 53 (50%) had been tested pre-operatively for OSA and 38 (38/53, 72%) were found to be sleep test positive. The median STOP-BANG score was 4, mean ± SD of 4.1 ± 1.1. These 38 patients became the OSA positive group. A control group of 38 OSA negative patients, matched for age, sex and pathology were selected. Their median STOP-BANG score was 2, mean ± SD of 2.3 ± 1.3. The distribution of the patients according to pathology in both groups is shown in Table 1. Of the patients with OSA 23 (61%) were using CPAP for OSA pre-operatively.
After getting the approval from institutional research ethics board, we retrospectively reviewed the charts of all patients who underwent transsphenoidal surgery in our institution from June 2006 to May 2011. The charts were retrieved from the institutional electronic patient record system. Data was collected from the patients’ anesthesia, postoperative anesthesia care unit (PACU), neurocritical care unit, intensive care unit (ICU), respiratory therapist and other health care records. Where possible we retrieved the pre-operative assessment data from clinical anesthesia information system. The outcome measures collected and analyzed include patient demographics, diagnosis, STOP-BANG score,[11] sleep-study history, the perioperative course including all complications and the post-operative management of OSA, when present. Postoperative desaturation was defined as an oxygen saturation (SaO2) 4. From this group, we identified those patients who had positive sleep study preoperatively. These patients were considered as OSA positive group. We then identified a control group (OSA negative) consisting of patients with either a negative sleep study result from the at risk group or with a negative STOP-BANG score. The control group was matched for age, sex and pathology to the OSA positive patients. The two groups were compared for the incidence of perioperative complications. Statistical analysis was done using t-test and Chi-square test as appropriate. P < 0.05 was considered as significant. All values expressed as mean ± standard deviation (SD).
Results We identified 469 patients who had transsphenoidal surgery (male:female, 227:242) with an age range from 19-89 years and a mean (±SD) age of 51 ± 16 years. 352
Demographics and anesthesia management are shown in Table 2. Overall, OSA patients had higher body mass index and higher incidence of hypertension and diabetes. The incidence of difficult mask ventilation was higher in patients with OSA when compared to those without OSA. But, there was no difference in the incidence of difficult intubation between the two groups. Intraoperative hypertension and hypotension requiring treatment occurred more frequently in the OSA group. Patients with OSA also had lower overall intraoperative PaO2 values and higher PaCO2 values. During surgery, only one patient had a brief period of hypoxia (SaO2 < 90) in OSA group due to endobronchial migration of endotracheal tube. There were no differences between the groups with regards to intraoperative opioid use. Table 1: Distribution of study patients according to pathology OSA positive (n = 38)* No preTotal Preoperative operative use of CPAP use of CPAP (n = 15) (n = 23) Acromegaly 14 7 7 Cushing’s disease 6 3 3 Craniopharyngioma 4 3 1 Prolactinoma 1 0 1 Non-secretory 8 6 2 macroadenoma Rathke’s cleft cyst 3 2 1 Skull-base tumors 2 2 0 Pathology type
OSA negative (n = 38)
14 6 1 1 14 1 1
*Pre-operative OSA testing positive. OSA = Obstructive sleep apnea, CPAP = Continuous positive airway pressure
Journal of Anaesthesiology Clinical Pharmacology | July-September 2014 | Vol 30 | Issue 3
Rahimi, et al.: Sleep apnea and transsphenoidal surgery
At the end of procedure all patients were safely extubated in the operating room. Their immediate post-operative care was in the PACU for all patients except one. This patient with OSA was electively transferred to the ICU due to a history of severe aortic stenosis. There were no complications in the PACU. There were no differences in the post-operative destination from PACU between the two groups [Table 3]. Table 2: Demographics and intraoperative events Patients characteristics
Male/female* Age (year)† BMI† History of hypertension* History of diabetes mellitus* Airway management* Difficult mask bag ventilation Intubation attempts >1 Intraoperative events Total fentanyl use (μg)† Episodes of hypotension* Episodes of hypertension* PaO2 (mmHg)† PaCO2 (mmHg)†
OSA positive (n = 38) 21/17 53±13 35±11 20 17
OSA negative (n = 38) 22/16 51±13 29±6 14 5
P value
6 3
0 3
0.0769 1.0000
253±73 26 30 158±63 37±7
268±111 11 20 224±44 33±6
0.4886 0.0019 0.0207
Perioperative management and complications in patients with obstructive sleep apnea undergoing transsphenoidal surgery: Our institutional experience Eiman Rahimi, Ramamani Mariappan, Suresh Tharmaradinam, Pirjo Manninen, Lashmi Venkatraghavan Department of Anesthesia, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
Abstract Background and Aims: Patients with endocrine diseases such as acromegaly and Cushing’s disease have a high prevalence of obstructive sleep apnea (OSA). There is controversy regarding the use of continuous positive airway pressure (CPAP) following transsphenoidal surgery. The aim of this study was to compare the perioperative management and complications, in patients with or without OSA undergoing transsphenoidal surgery. Materials and Methods: After Research Ethics Board approval, we retrospectively reviewed the charts of all patients who underwent transsphenoidal surgery in our institution from 2006 to 2011. Information collected included patients’ demographics, pathology of lesion, history of OSA, anesthetic and perioperative management and incidence of perioperative complications. Patients with sleep study proven OSA were compared with a control group, matched for age, sex and pathology of patients without OSA. Statistical analysis was performed using t-test and Chi-square test and the P < 0.05 was considered to be significant. Results: Out of a total 469 patients undergoing transsphenoidal surgery, 105 patients were found to be at risk for OSA by a positive STOP-BANG scoring assessment. Preoperative sleep study testing was positive for OSA in 38 patients. Post-operative hypoxemia (SpO2 < 90) occurred in 10 (26%) patients with OSA and was treated with high-flow oxygen through face mask (n = 7) and by CPAP mask (n = 3). In the OSA-negative group, 2 patients had hypoxemia and were treated with low-flow oxygen using face mask. There were no differences between the groups with respect to post-operative opioid use, destination, hospital stay or other complications. Conclusions: Post-operative hypoxemia in patients with OSA following transsphenoidal surgery can be treated in most but not all patients with high flow oxygen using the face mask. We were able to safely use CPAP in a very small number of patients but caution is needed to prevent complications. Further prospective studies are needed to determine the safe use of CPAP in patients after transsphenoidal surgery. Key words: Continuous positive airway pressure, obstructive sleep apnea, transsphenoidal surgery
Introduction Obstructive sleep apnea (OSA) is a common sleep related breathing disorder with prevalence between 2 and 25% in the Address for correspondence: Dr. Lashmi Venkatraghavan, Department of Anesthesia, Toronto Western Hospital, University Health Network, University of Toronto, 399 Bathurst Street, Toronto, Ontario, M5T 2S8 Canada. E-mail: [email protected] Access this article online Quick Response Code:
Website: www.joacp.org
DOI: 10.4103/0970-9185.137266
general population.[1] The incidence of OSA in patients with pituitary disease has been reported to be 60-80% in patients with acromegaly and 18-32% with Cushing’s disease.[2-4] The main surgical approach for pituitary surgery is transsphenoidal surgery. There is an increased incidence of perioperative complications among patients with OSA undergoing surgery under general anesthesia.[5] The American Society of Anesthesiologist practice guidelines for the perioperative management of patients with OSA recommends, the use of continuous positive airway pressure (CPAP) or non-invasive positive pressure ventilation with or without supplemental oxygen during the post-operative period in patients who were using these modalities pre-operatively, unless contraindicated by the surgical procedure.[6] The application of CPAP has generally been thought to be contraindicated after transsphenoidal surgery.[7] Complications from the use of CPAP include pneumocephalus especially in the presence of
Journal of Anaesthesiology Clinical Pharmacology | July-September 2014 | Vol 30 | Issue 3
351
Rahimi, et al.: Sleep apnea and transsphenoidal surgery
a cerebrospinal fluid (CSF) leak.[8,9] Currently, there are no relevant guidelines or consensus existing for the management of OSA in patients undergoing transsphenoidal surgery.[10] The aim of this study was to compare the perioperative management and complications, in patients with or without OSA undergoing transsphenoidal surgery in our institution.
Among these, 358 patients had pituitar y pathology consisting of acromegaly (53), Cushing’s disease (54), prolactinomas (41), craniopharyngioma (34), non-secretory macroadenoma (170) and other pituitary lesions (6). The transsphenoidal approach was used for excision of skull base pathology in 111 patients.
Materials and Methods
With the use of the STOP-BANG scoring scale, 105 (22%) patients were identified as high risk for OSA. Of these, 53 (50%) had been tested pre-operatively for OSA and 38 (38/53, 72%) were found to be sleep test positive. The median STOP-BANG score was 4, mean ± SD of 4.1 ± 1.1. These 38 patients became the OSA positive group. A control group of 38 OSA negative patients, matched for age, sex and pathology were selected. Their median STOP-BANG score was 2, mean ± SD of 2.3 ± 1.3. The distribution of the patients according to pathology in both groups is shown in Table 1. Of the patients with OSA 23 (61%) were using CPAP for OSA pre-operatively.
After getting the approval from institutional research ethics board, we retrospectively reviewed the charts of all patients who underwent transsphenoidal surgery in our institution from June 2006 to May 2011. The charts were retrieved from the institutional electronic patient record system. Data was collected from the patients’ anesthesia, postoperative anesthesia care unit (PACU), neurocritical care unit, intensive care unit (ICU), respiratory therapist and other health care records. Where possible we retrieved the pre-operative assessment data from clinical anesthesia information system. The outcome measures collected and analyzed include patient demographics, diagnosis, STOP-BANG score,[11] sleep-study history, the perioperative course including all complications and the post-operative management of OSA, when present. Postoperative desaturation was defined as an oxygen saturation (SaO2) 4. From this group, we identified those patients who had positive sleep study preoperatively. These patients were considered as OSA positive group. We then identified a control group (OSA negative) consisting of patients with either a negative sleep study result from the at risk group or with a negative STOP-BANG score. The control group was matched for age, sex and pathology to the OSA positive patients. The two groups were compared for the incidence of perioperative complications. Statistical analysis was done using t-test and Chi-square test as appropriate. P < 0.05 was considered as significant. All values expressed as mean ± standard deviation (SD).
Results We identified 469 patients who had transsphenoidal surgery (male:female, 227:242) with an age range from 19-89 years and a mean (±SD) age of 51 ± 16 years. 352
Demographics and anesthesia management are shown in Table 2. Overall, OSA patients had higher body mass index and higher incidence of hypertension and diabetes. The incidence of difficult mask ventilation was higher in patients with OSA when compared to those without OSA. But, there was no difference in the incidence of difficult intubation between the two groups. Intraoperative hypertension and hypotension requiring treatment occurred more frequently in the OSA group. Patients with OSA also had lower overall intraoperative PaO2 values and higher PaCO2 values. During surgery, only one patient had a brief period of hypoxia (SaO2 < 90) in OSA group due to endobronchial migration of endotracheal tube. There were no differences between the groups with regards to intraoperative opioid use. Table 1: Distribution of study patients according to pathology OSA positive (n = 38)* No preTotal Preoperative operative use of CPAP use of CPAP (n = 15) (n = 23) Acromegaly 14 7 7 Cushing’s disease 6 3 3 Craniopharyngioma 4 3 1 Prolactinoma 1 0 1 Non-secretory 8 6 2 macroadenoma Rathke’s cleft cyst 3 2 1 Skull-base tumors 2 2 0 Pathology type
OSA negative (n = 38)
14 6 1 1 14 1 1
*Pre-operative OSA testing positive. OSA = Obstructive sleep apnea, CPAP = Continuous positive airway pressure
Journal of Anaesthesiology Clinical Pharmacology | July-September 2014 | Vol 30 | Issue 3
Rahimi, et al.: Sleep apnea and transsphenoidal surgery
At the end of procedure all patients were safely extubated in the operating room. Their immediate post-operative care was in the PACU for all patients except one. This patient with OSA was electively transferred to the ICU due to a history of severe aortic stenosis. There were no complications in the PACU. There were no differences in the post-operative destination from PACU between the two groups [Table 3]. Table 2: Demographics and intraoperative events Patients characteristics
Male/female* Age (year)† BMI† History of hypertension* History of diabetes mellitus* Airway management* Difficult mask bag ventilation Intubation attempts >1 Intraoperative events Total fentanyl use (μg)† Episodes of hypotension* Episodes of hypertension* PaO2 (mmHg)† PaCO2 (mmHg)†
OSA positive (n = 38) 21/17 53±13 35±11 20 17
OSA negative (n = 38) 22/16 51±13 29±6 14 5
P value
6 3
0 3
0.0769 1.0000
253±73 26 30 158±63 37±7
268±111 11 20 224±44 33±6
0.4886 0.0019 0.0207
