Anaesthetic complications of acromegaly

Consensus guideline for the diagnosis and management of pituitary adenomas in childhood and adolescence: Part 2, specific diseases

Pituitary adenomas are rare in children and young people under the age of 19 (hereafter referred to as CYP) but they pose some different diagnostic and management challenges in this age group than in adults. These rare neoplasms can disrupt maturational, visual, intellectual and developmental processes and, in CYP, they tend to have more occult presentation, aggressive behaviour and are more likely to have a genetic basis than in adults. Through standardized AGREE II methodology, literature review and Delphi consensus, a multidisciplinary expert group developed 74 pragmatic management recommendations aimed at optimizing care for CYP in the first-ever comprehensive consensus guideline to cover the care of CYP with pituitary adenoma. Part 2 of this consensus guideline details 57 recommendations for paediatric patients with prolactinomas, Cushing disease, growth hormone excess causing gigantism and acromegaly, clinically non-functioning adenomas, and the rare TSHomas. Compared with adult patients with pituitary adenomas, we highlight that, in the CYP group, there is a greater proportion of functioning tumours, including macroprolactinomas, greater likelihood of underlying genetic disease, more corticotrophinomas in boys aged under 10 years than in girls and difficulty of peri-pubertal diagnosis of growth hormone excess. Collaboration with pituitary specialists caring for adult patients, as part of commissioned and centralized multidisciplinary teams, is key for optimizing management, transition and lifelong care and facilitates the collection of health-related quality of survival outcomes of novel medical, surgical and radiotherapeutic treatments, which are currently largely missing.

Surgical and non-surgical interventions for primary and salvage treatment of growth hormone-secreting pituitary adenomas in adults

BACKGROUND

Growth hormone (GH)-secreting pituitary adenoma is a severe endocrine disease. Surgery is the currently recommended primary therapy for patients with GH-secreting tumours. However, non-surgical therapy (pharmacological therapy and radiation therapy) may be performed as primary therapy or may improve surgical outcomes.

OBJECTIVES

To assess the effects of surgical and non-surgical interventions for primary and salvage treatment of GH-secreting pituitary adenomas in adults.

SEARCH METHODS

We searched CENTRAL, MEDLINE, WHO ICTRP, and ClinicalTrials.gov. The date of the last search of all databases was 1 August 2022. We did not apply any language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs of more than 12 weeks' duration, reporting on surgical, pharmacological, radiation, and combination interventions for GH-secreting pituitary adenomas in any healthcare setting.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts for relevance, screened for inclusion, completed data extraction, and performed a risk of bias assessment. We assessed studies for overall certainty of the evidence using GRADE. We estimated treatment effects using random-effects meta-analysis. We expressed results as risk ratios (RR) for dichotomous outcomes together with 95% confidence intervals (CI) or mean differences (MD) for continuous outcomes, or in descriptive format when meta-analysis was not possible.

MAIN RESULTS

We included eight RCTs that evaluated 445 adults with GH-secreting pituitary adenomas. Four studies reported that they included participants with macroadenomas, one study included a small number of participants with microadenomas. The remaining studies did not specify tumour subtypes. Studies evaluated surgical therapy alone, pharmacological therapy alone, or combination surgical and pharmacological therapy. Methodological quality varied, with many studies providing insufficient information to compare treatment strategies or accurately judge the risk of bias. We identified two main comparisons, surgery alone versus pharmacological therapy alone, and surgery alone versus pharmacological therapy and surgery combined. Surgical therapy alone versus pharmacological therapy alone Three studies with a total of 164 randomised participants investigated this comparison. Only one study narratively described hyperglycaemia as a disease-related complication. All three studies reported adverse events, yet only one study reported numbers separately for the intervention arms; none of the 11 participants were observed to develop gallbladder stones or sludge on ultrasonography following surgery, while five of 11 participants experienced any biliary problems following pharmacological therapy (RR 0.09, 95% CI 0.01 to 1.47; 1 study, 22 participants; very low-certainty evidence). Health-related quality of life was reported to improve similarly in both intervention arms during follow-up. Surgery alone compared to pharmacological therapy alone may slightly increase the biochemical remission rate from 12 weeks to one year after intervention, but the evidence is very uncertain; 36/78 participants in the surgery-alone group versus 15/66 in the pharmacological therapy group showed biochemical remission. The need for additional surgery or non-surgical therapy for recurrent or persistent disease was described for single study arms only. Surgical therapy alone versus preoperative pharmacological therapy and surgery Five studies with a total of 281 randomised participants provided data for this comparison. Preoperative pharmacological therapy and surgery may have little to no effect on the disease-related complication of a difficult intubation (requiring postponement of surgery) compared to surgery alone, but the evidence is very uncertain (RR 2.00, 95% CI 0.19 to 21.34; 1 study, 98 participants; very low-certainty evidence). Surgery alone may have little to no effect on (transient and persistent) adverse events when compared to preoperative pharmacological therapy and surgery, but again, the evidence is very uncertain (RR 1.23, 95% CI 0.75 to 2.03; 5 studies, 267 participants; very low-certainty evidence). Concerning biochemical remission, surgery alone compared to preoperative pharmacological therapy and surgery may not increase remission rates up until 16 weeks after surgery; 23 of 134 participants in the surgery-alone group versus 51 of 133 in the preoperative pharmacological therapy and surgery group showed biochemical remission. Furthermore, the very low-certainty evidence did not suggest benefit or detriment of preoperative pharmacological therapy and surgery compared to surgery alone for the outcomes 'requiring additional surgery' (RR 0.48, 95% CI 0.05 to 5.06; 1 study, 61 participants; very low-certainty evidence) or 'non-surgical therapy for recurrent or persistent disease' (RR 1.22, 95% CI 0.65 to 2.28; 2 studies, 100 participants; very low-certainty evidence). None of the included studies measured health-related quality of life. None of the eight included studies measured disease recurrence or socioeconomic effects. While three of the eight studies reported no deaths to have occurred, one study mentioned that overall, two participants had died within five years of the start of the study.

AUTHORS' CONCLUSIONS

Within the context of GH-secreting pituitary adenomas, patient-relevant outcomes, such as disease-related complications, adverse events and disease recurrence were not, or only sparsely, reported. When reported, we found that surgery may have little or no effect on the outcomes compared to the comparator treatment. The current evidence is limited by the small number of included studies, as well as the unclear risk of bias in most studies. The high uncertainty of evidence significantly limits the applicability of our findings to clinical practice. Detailed reporting on the burden of recurrent disease is an important knowledge gap to be evaluated in future research studies. It is also crucial that future studies in this area are designed to report on outcomes by tumour subtype (that is, macroadenomas versus microadenomas) so that future subgroup analyses can be conducted. More rigorous and larger studies, powered to address these research questions, are required to assess the merits of neoadjuvant pharmacological therapy or first-line pharmacotherapy.

Vascular anomalies in patients with growth hormone-secreting pituitary adenomas: illustrative case report and systematic review of the literature

PURPOSE

Endonasal resection is the first-line treatment for patients harboring growth hormone (GH)-secreting pituitary adenomas. The complexity of the parasellar neurovascular structures makes pre-operative diagnostic imaging essential to understanding the anatomy of this region. We aimed to describe vascular anomalies in acromegalic patients and emphasize their relevance for surgery and preoperative planning.

METHODS

A systematic review following the PRISMA statement was performed in July 2021.

RESULTS

Thirty-three studies were evaluated. Elevated GH and insulin-like growth factor-1 (IGF-1) levels are linked to the occurrence of cardiovascular risk factors. This is attributed to endothelial dysfunction, mainly caused by changes in flow-mediated dilatation (FMD), which is probably the main cause of vascular anomalies in acromegaly. The occurrence of protrusions of the internal carotid artery (ICA) (35-53%), a narrow intercarotid distance, and an asymmetrical course was described. In 13-18% of acromegalic patients, the presence of an intracerebral aneurysm could be reported (incidence in the general population:0.8-1.3%). The selected studies were however performed with a small patient sample (range:1-257). We present a case report of a 57y/o male patient with anomalies of the ICA ("kissing carotid arteries") harboring a GH-secreting adenoma, which was resected via an endoscopic endonasal approach.

CONCLUSIONS

There is an association between acromegaly and endothelial dysfunction, which increases cardiovascular risk factors and vascular anomalies. Preoperative vascular imaging, e.g., CT angiography, should be implemented as a standard to identify patients at risk and estimate surgical morbidity. However, no evidence-based recommendations exist so far, so future studies are necessary.

Optimizing Perioperative Care in Transsphenoidal Pituitary Surgery: Considerations for Enhanced Recovery After Surgery

OBJECTIVE

To identify key recommendations for maximizing the efficiency and efficacy of perioperative care in transsphenoidal pituitary surgery.

METHODS

The authors performed a comprehensive literature search of Enhanced Recovery After Surgery protocols implemented for patients undergoing transsphenoidal adenomectomy (TSA); individual recommendations were abstracted, and the evidence base thoroughly reviewed.

RESULTS

The authors identified 19 individual recommendations pertinent to the care of patients undergoing TSA, which were subdivided into preoperative (n=6), intraoperative (n=6), and postoperative (n=7) interventions. Key factors recommended for minimizing length of stay, preventing readmission, and improving patient outcomes included comprehensive patient education, multidisciplinary evaluation, avoidance of routine lumbar drain placement and nasal packing, and rigorous postoperative monitoring of pituitary function and salt-water imbalances. The overall level of evidence for 7/19 (37%) implemented recommendations was found to be low, suggesting a need for continued research in this patient population.

CONCLUSION

Several key interventions should be considered in the development of Enhanced Recovery After Surgery protocols for TSA, which may aid in further decreasing length of stay and promoting positive patient outcomes.

Preoperative Medical Treatment for Patient with Acromegaly: yes or no?

Transsphenoidal surgery is the first-line treatment for acromegaly. However, several factors can modify surgical remission rates, such as the initial hormone levels, the size and invasiveness of the tumor, and the degree of experience of the surgeon. Physicians treating patients with acromegaly should thus consider how to improve surgical remission rates. As stated in recent guidelines, the major point is to consider that any patient with acromegaly should be referred to an expert neurosurgeon to maximize the chances of surgical sure. The benefits of presurgical medical treatment, mainly using somatostatin receptor ligands (SRLs), given 3 to 6 months before surgery, remain controversial. By normalizing growth hormone and insulin-like growth factor 1 levels, SRLs may improve the overall condition of the patient, thus decreasing anesthetic and surgical complications. By decreasing the tumor size and modifying the consistency of the tumor, SRLs might also make surgical excision easier. This is however theoretical as published data are contradictory on both points, and only limited data support the use of a systematical presurgical medical treatment. The aim of this review is to analyze the potential benefits and pitfalls of using presurgical medical treatment in acromegaly in view of the contradictory literature data. We also attempt to determine the profile of patients who might most benefit from this presurgical medical treatment approach as an individualized therapeutic management of acromegaly.

Insulin-like growth factor-1 as predictive factor of difficult laryngoscopy in patients with GH-producing pituitary adenoma: A pilot study

BACKGROUND

Growth hormone (GH)-producing pituitary tumors account for 10 to 15% of pituitary tumors. The hypersecretion of GH may induce changes in the airway anatomy through the activation of Insulin-like Growth factor 1(IGF-1) pathway. We sought investigate the role IGF-1 as a potential predictive factor of difficult laryngoscopy in patients with GH-producing pituitary adenoma.

METHODS

This study was a single center retrospective study. We included 33 patients undergoing transsphenoidal resection of GH-producing pituitary. We recorded demographic data, el-Ganzouri risk index (EGRI) and modified Look-Evaluate-Mallampati-Obstruction-Neck mobility (mLEMON) score, and pituitary hormone plasma levels. We performed ordinal logistic regression to analyze the relationship between IGF-1 and EGRI, mLEMON, and Cormack-Lehane Grade score and a multiple logistic regression to test the capability of EGRI, mLEMON and IGF-1 levels to predict Cormack-Lehane score. Receiver operating curve (ROC), area under the curve (AUC), and cut-off value of IGF-1 were calculated.

RESULTS

Only 14 (42.8%) and 12 (36.36%) patients showed predictive factors of difficult intubation according to EGRI and mLEMON score, respectively. IGF-1 significantly correlated with Cormack-Lehane (p = 0.005879) but not with mLEMON and EGRI (p = 0.3080 and 0.4146, respectively). In multiple regression model IGF-1 correlated only with Cormack-Lehane grade (p = 0.0089). Area under ROC was 0.8571 and cut-off value of IGF-1 was 186.15 ng/ml.

CONCLUSION

Higher IGF-1 levels correlate with the probability of having a higher Cormack-Lehane score; classical bedside scores, such as mLEMON and EGRI, were not able to predict difficult laryngoscopy in our population.

Optimizing pre-, intra-, and postoperative management of patients with sellar pathology undergoing transsphenoidal surgery

OBJECTIVE

Perioperative management of patients with sellar lesions is complex, requiring input from a multidisciplinary team of specialists for ongoing management of both endocrinological and neurosurgical issues. Here, the authors reviewed the experience of a single multidisciplinary center over 10 years to identify key postoperative practices that ensure positive outcomes for patients with sellar lesions who undergo transsphenoidal surgery.

METHODS

The authors performed a retrospective review of all transsphenoidal operations carried out by the senior author at a single center from April 2008 through November 2018. They included only adult patients and recorded perioperative management. They also reviewed the evolution of clinical practices for perioperative care at their institution to identify strategies for ensuring positive patient outcomes, and they reviewed the literature on select related topics.

RESULTS

In total, 1023 operations in 928 patients were reviewed. Of these, 712 operations were for pituitary adenomas (69.6%), and 122 were for Rathke cleft cysts (11.9%). The remainder included operations for craniopharyngiomas (3.6%), arachnoid cysts (1.7%), pituitary tumor apoplexy (1.0%), and other sellar pathologies (12.2%). Among the reviewed operations, the median hospital stay was 3 days (IQR 2-3). Patient management details during the pre-, intra-, and postoperative periods were identified, including both shared characteristics of all patients undergoing transsphenoidal surgery and unique characteristics that are specific to certain lesion types or patient populations.

CONCLUSIONS

Patients with sellar lesions who undergo transsphenoidal surgery require complex, multidisciplinary perioperative care to monitor for common adverse events and to improve outcomes, but there is a dearth of high-quality evidence guiding most perioperative practices. Here, the authors reviewed practices at their institution across more than 1000 transsphenoidal operations that may help ensure successful patient outcomes.

Lung function and blood gas abnormalities in patients with acromegaly

OBJECTIVE

Respiratory disorders are common complications of acromegaly patients. We conducted a large-scale survey in the patients with acromegaly and demonstrated the characteristics of their lung function and blood gas.

METHODS

A prospective cohort study was conducted with 115 patients with active acromegaly and 56 patients with nonfunctioning pituitary adenomas. All patients underwent clinical, biological, radiological, lung functional and blood gas assessments.

RESULTS

Acromegaly patients had a higher lung volume than those with nonfunctioning adenomas (forced vital capacity value (FVC) and FVC% predicted: p < 0.001). The small airway was less obstructive in acromegaly patients (higher FEV1% predicted, PEF% predicted, MEF75% predicted, MEF50% predicted, MEF25% predicted: p ≤ 0.001 for all analyses, FEV1/FVC: p = 0.151). The average partial pressure of carbon dioxide in acromegaly patients was higher (p < 0.001), but there was no significant difference in the average partial pressure of oxygen or oxygen saturation between the two groups (p > 0.05). In acromegaly patients, the average age of patients with small airway obstruction was higher than that of patients with normal lung function (p < 0.05), but no significant difference in GH or IGF-1 levels between the two groups were found (p > 0.05).

CONCLUSION

The acromegaly patients in this cohort had increased lung volume. However, there was no evidence demonstrating hypoxemia in acromegaly patients. The small airway was less obstructive in acromegaly patents. Small airway obstruction was observed in elderly patients with acromegaly.

Pretreatment with somatostatin analogs does not affect the anesthesiologic management of patients with acromegaly

PURPOSE

Acromegaly may be associated with an increased risk of complex intraoperative management and anesthetic complications. No study addressed whether pretreatment with somatostatin receptor ligands (SRLs) affects anesthesiologic management.

METHODS

We studied 211 consecutive acromegalic patients who had a recorded intraoperative computerized anesthetic record (ICAR) available for analysis. Ninety-six (45.5%) patients were SRL-pretreated while 115 patients were treatment naïve.

RESULTS

Treatment with SRLs reduced mean basal growth hormone level from 23.8 ± 4.2 to 5.9 ± 1.3 µg/L. Normalization of insulin-like growth factor-1 was achieved in 26 patients (27.1%). The frequency of comorbidities at surgery was similar in the two groups. Five patients with difficult intubation were naïve (4.3%) as compared with 5 SRL-pretreated patients (5.2%; P = 1.0). ICAR registration did not show any significant change of intraoperative vital parameters in the two groups of patients as well as in the intraoperative utilization of drugs. Total duration of anesthesia and surgery were similar in the two groups. Four patients with an intraoperative adverse event were naïve (3.5%) as compared with 4 SRL-pretreated patients (4.2%; P = 1.00). Remission of disease occurred in 83 of 114 naïve patients (72.8%) and in 57 of 93 SRL-pretreated patients (61.3%; P = 0.11).

CONCLUSIONS

SRL-pretreatment of patients with acromegaly had no significant impact on intraoperative anesthesiologic management. Despite a better Cormack-Lehane score in SRL-pretreated than in naïve patients, the rate of difficult intubation was similar in both groups. SRL-pretreatment did not affect the rate of surgical remission or complications as well.

Systemic Complications of Acromegaly and the Impact of the Current Treatment Landscape: An Update

Acromegaly is a chronic systemic disease with many complications and is associated with increased mortality when not adequately treated. Substantial advances in acromegaly treatment, as well as in the treatment of many of its complications, mainly diabetes mellitus, heart failure, and arterial hypertension, were achieved in the last decades. These developments allowed change in both prevalence and severity of some acromegaly complications and furthermore resulted in a reduction of mortality. Currently, mortality seems to be similar to the general population in adequately treated patients with acromegaly. In this review, we update the knowledge in complications of acromegaly and detail the effects of different acromegaly treatment options on these complications. Incidence of mortality, its correlation with GH (cumulative exposure vs last value), and IGF-I levels and the shift in the main cause of mortality in patients with acromegaly are also addressed.

High levels of IGF-1 predict difficult intubation of patients with acromegaly

PURPOSE

To investigate the characteristics of difficult intubation and identify novel efficient predictors in patients with acromegaly.

METHODS

Patients with either untreated acromegaly or non-functional pituitary adenomas were enrolled. Patients with acromegaly underwent hormone assays, upper airway computed tomography and magnetic resonance imaging examinations and preoperative overnight polysomnography. The modified Mallampati classification, mouth opening, neck circumference, and neck extension were assessed, and the Cormack-Lehane grades and the time of tracheal intubation were recorded.

RESULTS

Patients with acromegaly had a higher incidence of difficult intubation (62.5%). The time of tracheal intubation was prolonged, the neck circumference was enlarged, and the neck extension was confined. In patients with acromegaly and difficult intubation, the insulin-like growth factor 1 levels and apnea/hypoxia index were significantly higher compared to patients without difficult intubation (1115.40 ± 253.73 vs. 791.67 ± 206.62 ng/ml, P = 0.020; 22.17 ± 23.25 vs. 2.47 ± 2.84, P = 0.026, respectively). The bilateral regression analysis revealed that high levels of insulin-like growth factor 1 were an independent risk factor for developing difficult intubation (p = 0.042, Exp B = 1.006). The modified Mallampati classification was positively correlated with apnea/hypoxia index and could be calculated using the following logarithmic equation: MMC = 0.2982 * ln (AHI) + 2.1836.

CONCLUSIONS

In patients with acromegaly, neck movement is confined, the time of tracheal intubation is prolonged, and the neck circumference is enlarged, and these patients suffer from an increased incidence of difficult intubation (62.5%) during anesthesia induction. The apnea/hypoxia index and insulin-like growth factor 1 levels are both increased in acromegalic patients with difficult intubation, and elevated insulin-like growth factor 1 levels are an independent risk factor of difficult intubation in acromegalic patients.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY DISEASE STATE CLINICAL REVIEW: MANAGEMENT OF ACROMEGALY PATIENTS: WHAT IS THE ROLE OF PRE-OPERATIVE MEDICAL THERAPY?

OBJECTIVE

Acromegaly is a complex disease characterized by growth hormone (GH) excess originating in most cases from a pituitary tumor. The goals of treatment include removing the tumor or reducing tumor burden, normalizing GH secretion and insulin-like growth factor 1 levels, and preserving normal pituitary function if possible. Surgery by an experienced neurosurgeon is still considered first-line therapy, especially in cases with small tumors. In the last few decades, significant progress in the development of selective pharmacologic agents has greatly facilitated the management of active acromegaly, with agents such as somatostatin-receptor ligands (SRLs), GH-receptor antagonists, and dopamine agonists. In addition to adjuvant treatment, pre-operative medical therapy and primary therapy in de novo patients are increasingly employed.

METHODS

A United States National Library of Medicine PubMed search (through July 2014) was conducted for the following terms: acromegaly, pre-operative medical therapy, somatostatin-receptor ligands, and somatostatin analogs. Articles not in English and those not in peer-reviewed journals were excluded. In reviewing pertinent articles, focus was placed on biochemical and other postoperative outcomes of medical therapy.

RESULTS

An analysis of the full effect of pre-operative use of SRLs on surgical outcomes (remission rates and peri-operative complications) is limited by heterogeneity of methodology, low overall surgical cure rates, and different study designs. The assumption that SRL use prior to surgery reduces peri-operative surgical risk has yet to be proven. A variable degree of tumor shrinkage with preoperative SRLs is observed. Likewise, SRL treatment 3 months before surgery may improve surgical remission rates in the short term; however, positive results do not persist in the long term.

CONCLUSION

We consider that medical therapy before surgery could play a role in carefully selected patients, but treatment should be individualized. Primary medical therapy with a SRL may be considered in patients with macroadenomas without local mass effects on the optic chiasm, as SRLs have been shown to reduce tumor size and control GH hypersecretion. However, the data are insufficient to support general use of a SRL prior to surgery in order to improve post-surgery biochemical outcomes. Theoretically, patients with severe cardiac and respiratory complications due to acromegaly could potentially benefit from pre-operative SRLs in order to reduce peri-operative morbidity. Further investigation and investment in large randomized long-term clinical trials are needed to define the precise role and duration of pre-surgical medical treatment in acromegaly patients.

Should all patients with acromegaly receive somatostatin analogue therapy before surgery and, if so, for how long?

Current guidelines do not recommend the routine use of somatostatin analogue pretreatment prior to surgery in patients with growth hormone-secreting pituitary tumours. In theory, presurgical use of somatostatin analogues should improve metabolic control and reduce soft tissue swelling, leading to improved anaesthetic outcomes. Shrinkage of tumours prior to surgery might also improve surgical remission rates. Hence, this article addresses the question: Should all patients with acromegaly receive a somatostatin analogue prior to surgery? Clinical trials published before December 2013 were reviewed, although literature in this area remains relatively deficient. We conclude: (i) On the basis of limited data available, somatostatin analogue pretreatment does not improve anaesthetic or immediate postoperative outcomes (i.e. hospital stay, rates of surgical complications and postoperative pituitary dysfunction). (ii) Somatostatin analogues should be considered in all patients with growth hormone-secreting macroadenomas, including invasive macroadenomas, when the overall surgical remission rate for macroadenomas at the treating centre is below 50%. Four recent RCTs have demonstrated increased rates of surgical remission using such an approach. (iii) When deemed appropriate, patients should be treated with somatostatin analogues for at least 3 months before surgery; there is currently no evidence that treatment beyond 6 months provides any additional benefit. Patients with minimally invasive macroadenomas are those most likely to benefit in terms of improved surgical remission.

Clinical applications of somatostatin analogs for growth hormone-secreting pituitary adenomas

Excessive growth hormone (GH) is usually secreted by GH-secreting pituitary adenomas and causes gigantism in juveniles or acromegaly in adults. The clinical complications involving cardiovascular, respiratory, and metabolic systems lead to elevated morbidity in acromegaly. Control of serum GH and insulin-like growth factor (IGF) 1 hypersecretion by surgery or pharmacotherapy can decrease morbidity. Current pharmacotherapy includes somatostatin analogs (SAs) and GH receptor antagonist; the former consists of lanreotide Autogel (ATG) and octreotide long-acting release (LAR), and the latter refers to pegvisomant. As primary medical therapy, lanreotide ATG and octreotide LAR can be supplied in a long-lasting formulation to achieve biochemical control of GH and IGF-1 by subcutaneous injection every 4-6 weeks. Lanreotide ATG and octreotide LAR provide an effective medical treatment, whether as a primary or secondary therapy, for the treatment of GH-secreting pituitary adenoma; however, to maximize benefits with the least cost, several points should be emphasized before the application of SAs. A comprehensive assessment, especially of the observation of clinical predictors and preselection of SA treatment, should be completed in advance. A treatment process lasting at least 3 months should be implemented to achieve a long-term stable blood concentration. More satisfactory surgical outcomes for noninvasive macroadenomas treated with presurgical SA may be achieved, although controversy of such adjuvant therapy exists. Combination of SA and pegvisomant or cabergoline shows advantages in some specific cases. Thus, an individual treatment program should be established for each patient under a full evaluation of the risks and benefits.

Airway management and perioperative concerns in acromegaly patients undergoing endoscopic transsphenoidal surgery for pituitary tumors

OBJECTIVES

Patients with acromegaly present unique challenges to cranial base surgery and anesthesia teams in the perioperative period, especially with regard to airway management. Abnormal airway anatomy may result from soft tissue hypertrophy and bony alterations. Additional perioperative challenges relate to the management of medical comorbidities. We aim to review perioperative airway concerns in acromegalic patients for the skull base surgeon in order to reduce preventable perioperative complications.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary care academic institution.

SUBJECTS

Thirty-two acromegaly patients undergoing endoscopic transsphenoidal pituitary surgery.

RESULTS

Videoscopic direct laryngoscopy intubation was required in 7 of 32 patients (21.9%) and fiberoptic intubation in 4 of 32 patients (12.5%). Overall failure rate for first intubation technique used was 12.5% (4/32). Cardiovascular comorbidities (hypertension and conduction abnormalities predominated) were present in 16 of 32 patients (50%), and obstructive sleep apnea, or other respiratory conditions, existed in 12 of 32 patients (37.5%).

CONCLUSIONS

Acromegaly patients present a particular challenge to the endoscopic skull base surgeon. Despite preoperative anesthesia and otolaryngology evaluation, many of these patients will experience an unanticipated airway challenge during intubation. Preoperative preparation and perioperative awareness of anatomic and physiologic abnormalities of acromegalic patients is essential for successful endoscopic surgery in this unique population.

Anesthesia in a 12 year old boy with somatic overgrowth secondary to pericentric inversion of chromosome 12

The management of a splenectomy in a boy with an unusual form of somatic overgrowth is presented. Except for a moderately difficult airway, no unusual reactions to anesthesia and surgery were encountered. Possible anesthetic implications of different somatic overgrowth syndromes in children are presented.

Pituitary Surgery and Anesthetic Management: An Update

Out of all the brain tumors, 10% are pituitary tumors. Surgical interventions in this field have advanced and so have techniques of anesthesia and intensive care. Presenting features of the patients with pituitary tumors are often due to excessive or decreased secretion of hormones. Most commonly performed procedure is transsphenoidal pituitary surgery which requires skillful anesthetic technique as a number of associated comorbidities may exist. For a positive surgical result, a team consisting of endocrine surgeon, endocrinologist, neurosurgeon and anesthesiologist is a must. An emphasis is required on preoperative evaluation of airway, endocrinal and neurological status. The understanding of pathophysiology, perioperative anesthetic management, awareness of likely complications and postoperative care, results in successful outcome.

How to cite this article

Malhotra SK, Sharma K, Saini V. Pituitary Surgery and Anesthetic Management: An Update. World J Endoc Surg 2013;5(1):1-5.

[Orotracheal intubation of patients with acromegaly using the AirTraq laryngoscope]

An excess of growth hormone is responsible for the phenotypical characteristics of acromegaly. Tissue hypertrophy and growth also affect the airway, potentially making perioperative management difficult. If tests to foresee the likelihood of difficult airway have limitations affecting their sensitivity, specificity and predictive value even in the normal population, their reliability in patients with acromegaly is still more doubtful. At this time, videoassisted or optical laryngoscopes can offer a way to facilitate intubation in these patients. We report 3 cases in which the AirTraq optical laryngoscope was used to gain a full view of the vocal cords in acromegalic patients scheduled for pituitary surgery by the transsphenoidal route.

Transsphenoidal surgery in patients with acromegaly: operative strategies for overcoming technically challenging anatomical variations

OBJECT

In addition to difficulties with anesthetic and medical management, transsphenoidal operations in patients with longstanding acromegaly are associated with inherent intraoperative challenges because of anatomical variations that occur frequently in these patients. The object of this study was to review the overall safety profile and anatomical/technical challenges associated with transsphenoidal surgery in patients with acromegaly.

METHODS

The authors performed a retrospective analysis of 169 patients who underwent endoscopic transsphenoidal operations for growth hormone-secreting adenomas to assess the incidence of surgical complications. A review of frequently occurring anatomical challenges and operative strategies employed during each phase of the operation to address these particular issues was performed.

RESULTS

Of 169 cases reviewed, there was no perioperative mortality. Internal carotid artery injury occurred in 1 patient (0.6%) with complex sinus anatomy, who remained neurologically intact following endovascular unilateral carotid artery occlusion. Other complications included: significant postoperative epistaxis (5 patients [3%]), transient diabetes insipidus (5 patients [3%]), delayed symptomatic hyponatremia (4 patients [2%]), CSF leak (2 patients [1%]), and pancreatitis (1 patient [0.6%]). Preoperative considerations in patients with acromegaly should include a cardiopulmonary evaluation and planning regarding intubation and other aspects of the anesthetic technique. During the nasal phase of the transsphenoidal operation, primary challenges include maintaining adequate visualization and hemostasis, which is frequently compromised by redundant, edematous nasal mucosa and bony hypertrophy of the septum and the nasal turbinates. During the sphenoid phase, adequate bony removal, optimization of working space, and correlation of imaging studies to intraoperative anatomy are major priorities. The sellar phase is frequently challenged by increased sellar floor thickness, distinct patterns of tumor extension and bony invasion, and anatomical variations in the caliber and course of the internal carotid artery. Specific operative techniques for addressing each of these intraoperative challenges are discussed.

CONCLUSIONS

Transsphenoidal surgery in patients with longstanding acromegaly frequently poses greater challenges than operations for other types of sellar lesions, yet these challenges may be safely and effectively overcome with the anticipation of specific issues and implementation of various intraoperative techniques.

Significance of postoperative fluid diuresis in patients undergoing transsphenoidal surgery for growth hormone–secreting pituitary adenomas

Object

Following successful transsphenoidal surgery in patients with growth hormone (GH)–secreting pituitary adenomas, a characteristic fluid diuresis has been described. In this paper the authors aimed to further analyze the degree of fluid diuresis as it relates to postoperative GH levels.

Methods

Between 2000 and 2008, 85 patients underwent transsphenoidal surgery for a GH-secreting adenoma at the USC University Hospital. A retrospective chart review was conducted. Postoperative fluid intake, output, and balance within 48 hours following surgery, as well as endocrinological data were recorded and analyzed. Patients with postoperative diabetes insipidus and those with insufficient data were excluded from analysis.

Results

Seventy-one patients were included in the analysis. The mean age was 46 years (range 16–74 years). There were 36 males (51%) and 35 females (49%). Patients with negative fluid balances at 48 hours after surgery were more than twice as likely to have a GH level of < 1.5 ng/ml (55 vs 25%, p = 0.023). At 48 hours after surgery, patients with a negative overall fluid balance had a significantly lower median GH level than those with a positive overall fluid balance (1.3 vs 2.4 ng/ml, p = 0.039). This difference was even more pronounced in patients with microadenomas and a negative overall fluid balance. By 48 hours following surgery, patients with postoperative Day 1 GH levels < 1.5 ng/ml had, on average, experienced diuresis of fluid > 1.1 L (median 1.5 L) more than patients with GH levels > 1.5 ng/ml.

Conclusions

Successful resection of GH-secreting adenomas is associated with a more pronounced fluid diuresis and negative overall fluid balance within 48 hours following transsphenoidal surgery. Patients with a negative fluid balance by postoperative Day 2 have a higher likelihood of having significantly reduced postoperative GH levels that may correlate with long-term surgical remission.

Treatment of elderly acromegalics

We assessed the incidence of elderly patients in Japanese acromegalics and the characteristics of their clinical presentation. We also evaluated the safety and efficacy of transsphenoidal surgery (TSS) in this patient group. During the 28-year period from 1980 to 2007 we treated 290 patients with acromegaly at our hospitals. Of these, 9 (3.1%) were elderly, i.e. 70 years old or older. They comprised 0.7% of acromegalics treated during the first- and 4.5% of patients with acromegaly treated during the 2nd 14-year period. Before treatment, all manifested abnormal glucose tolerance; 6 had diabetes mellitus (DM), 6 presented with hypertension, and 2 had cardiovascular disease, malignant neoplasms, or hyperlipidemia. Of the 7 elderly acromegalics who underwent TSS none manifested surgical morbidity or new pituitary hormone deficiencies. Postoperatively, the nadir growth hormone (GH) level at the oral glucose tolerance test (OGTT) was under 1.0 ng/mL in 5 patients, insulin-like growth factor (IGF-1) levels normalized in 4. Glucose tolerance improved in all operated patients. Only 1 of 6 patients with preoperatively diagnosed DM continued to manifest DM post-treatment, anti-hypertensive drugs could be tapered in 3 of patients with preoperative hypertension. In conclusion, we found that there was a high incidence of abnormal glucose tolerance and hypertension in elderly acromegalics, that surgical treatment was effective and safe in this population, and that it was useful for the control of co-morbidities.

Guidelines for the treatment of growth hormone excess and growth hormone deficiency in adults

The V Consensus Group Meeting on 'Guidelines for Treatment of GH Excess and GH Deficiency in the Adult' was an international workshop held on February 20-22, 2006 in Santa Monica, California, USA. The principal aim of this meeting was to provide guidelines for the evaluation and treatment of adults with either form of abnormal GH secretion: GH excess or GH deficiency. The workshop included debates as to the choice of primary treatment, discussions of the targets for adequate treatment, and concluded with presentations on open issues germane to adult GH treatment including the role of GH in malignancies, the impact of longterm treatment on bone, and a cost-benefit analysis. The meeting was comprised of 66 delegates representing 13 different countries.

Complications of transsphenoidal surgery in patients with pituitary adenoma: experience at a single centre

OBJECTIVE

This paper reports the complications of transsphenoidal surgery for pituitary adenomas in a series of 1240 consecutive patients operated at our Institute between 1990 and 2004 (first operations) and indicate the clinical characteristics of patients which affected surgical morbidity and mortality.

METHODS

According to tumour type, there were 420 (33.9%) non-functioning pituitary adenomas (NFPA), 349 (28.1%) GH-secreting, 288 (23.2%) ACTH-secreting, 155 (12.5%) prolactin (PRL)-secreting, and 28 (2.3%) TSH-secreting adenomas. The mean age of patients was 43.7 +/- 0.4 yr and 122 patients (9.9%) were 65 yr or older; the female/male ratio was 1.5/1. There were 370 (29.8%) microadenomas and 870 (70.2%) macroadenomas of which 54 (4.4%) were giant adenomas.

RESULTS

The series mortality was 0.2%, the medical morbidity 1.9%, and the surgical morbidity 3.5%. Medical complications were significantly more frequent in patients older than 65 yr (4.9 vs. 1.4%; p = 0.009) and in patients with giant adenomas (5.6 vs. 1.6%; p = 0.03). Multivariate analysis showed that both variables were independently associated with a higher morbidity rate. The surgical morbidity was increased in giant adenomas (15 vs. 3%; p = 0.0001), in NFPA (6.2 vs. 2.1% in secreting adenomas; p = 0.0002) and in patients older than 65 yr (6.6 vs. 3.1%; p = 0.05). Multivariate analysis showed that only giant size was independently associated with an increased surgical morbidity rate.

CONCLUSIONS

In our experience, the size of the adenoma was a risk factor for medical and surgery related complications and age over 65 yr for medical complications alone.

Presurgical treatment with somatostatin analogs in patients with acromegaly: effects on the remission and complication rates

Object

The question of whether preoperative therapy with somatostatin analogs can improve surgical outcome in acromegaly has not been definitively answered. In this paper, the authors report the effects of preoperative treatment with somatostatin analogs in a large sample of patients with acromegaly.

Methods

Between 1990 and 2003, 399 consecutive patients with acromegaly underwent surgery at the Istituto Scientifico San Raffaele. Thirty-three patients who had previously undergone surgery or radiation treatment, 48 patients treated with somatostatin analogs for fewer than 3 months, and patients who had stopped therapy for too long a time before surgery were excluded from the study. One hundred forty-three patients who had received somatostatin analogs prior to surgery (Group 1) were randomly matched to 143 patients who had never been treated with somatostatin analogs (Group 2). Matching criteria were tumor size and invasiveness into the cavernous sinus. Before surgery, Group 1 patients showed reduction of growth hormone levels to less than 50% of baseline in 64% of cases, but insulin-like growth factor–I was normalized in only 19.5%. Surgical remission occurred in 81 Group 1 patients (56.6%) and in 91 Group 2 patients (63.6%; p = 0.28). No significant difference in the remission rate was observed when cases were analyzed according to tumor size or invasiveness. Logistic regression analysis confirmed that pretreatment with somatostatin analogs was not associated with surgical outcome. Surgical morbidity was mild and similar in Group 1 and Group 2 patients (7 and 5.6%, respectively; p = 0.81). Surgical remission and complication rates in patients with acromegaly who received treatment with somatostatin analogs prior to surgery were not significantly different from those of matched patients who did not receive these agents.

Conclusions

At present, the routine use of presurgical therapy with somatostatin analogs for patients with acromegaly cannot be recommended.

Anaesthesia for pituitary surgery

The anaesthetic care of patients undergoing pituitary surgery involves an understanding of the varied presentations of pituitary disease and their implications for the patient's perioperative condition and management. The neuroanaesthetist must also have an appreciation of the issues relevant to the surgical approach (either transsphenoidal or, less commonly, transcranial) and be able to anticipate and manage them accordingly.

The place of pegvisomant in the acromegaly treatment algorithm

The disfiguring disease acromegaly results from hypersecretion of growth hormone (GH). The main goals of treatment for acromegaly include normalisation of biochemical markers of disease activity to restore normal life expectancy, amelioration of signs and symptoms of the disease, removal of the pituitary tumour without damaging the optic chiasm and other peripituitary structures, and preservation of pituitary function. Conventional options for treatment of acromegaly include surgery, radiotherapy (RT), and medical therapy with either dopamine agonists or somatostatin (SMS) analogues. The advent of the genetically engineered growth hormone analogue pegvisomant is unlikely to alter significantly the place of surgery and RT in the treatment algorithm for acromegaly biochemical control as determined based on serum IGF-I concentrations is achievable with pegvisomant in virtually all patients, and it will clearly become the drug of choice in patients partially or completely unresponsive to SMS analogues. Preliminary studies suggest improved insulin sensitivity for a given IGF-I with pegvisomant compared with SMS analogues; if these results are confirmed by results of future studies, such a metabolic advantage may encourage the use of pegvisomant.

Upper airway diseases and airway management: a synopsis

This article summarizes some of the more important upper airway conditions likely to affect airway management. A number of upper airway conditions may present difficult challenges to the anesthesiologist. For instance, infected airway structures may lead to partial airway obstruction, stridor, or even complete airway obstruction. Partial airway obstruction may be mild, as in snoring or nasal congestion, or may be more severe, perhaps requiring the use of airway adjuncts, such as a nasopharyngeal airway. Complete airway obstruction is usually managed by prompt intubation, but surgical airways are sometimes needed as a last resort.

Respiratory complications associated with anesthesia

Adverse pulmonary outcomes that follow anesthesia and surgery are often attributed to anesthesia care. PPCs are a significant concern for anesthesia caregivers because they use drugs and techniques that temporarily decrease lung volume, impair airway reflexes, limit immune function, and depress secretion mobilization. A significant component of perioperative risk derives from the surgical site, postoperative pain, and effects of pharmacologic pain management. Rapidly evolving surgical and anesthesia techniques and the introduction of newer pharmaceutical agents make it difficult to identify best practice from retrospective experience reported in the perioperative literature. Prospective studies that deal with specific patient populations, incomparable patient groups or techniques, and unique practice bias have limited validity of claims regarding several promising approaches to perioperative risk reduction. In the absence of clear scientific principles, a perioperative pulmonary risk management strategy for the early part of this century is based on the consensus practice of informed clinicians (Box 4).