Postoperative Pain in Complex Ophthalmic Surgical Procedures: Comparing Practice with Guidelines

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1 bs_bs_banner Pain Medicine 2014; 15: Wiley Periodicals, Inc. Postoperative Pain in Complex Ophthalmic Surgical Procedures: Comparing Practice with Guidelines Mladen Lesin, MD, MSc,* Zeljka Duplancic Sundov, MD,* Marko Jukic, MD, PhD, and Livia Puljak, MD, PhD *Department of Ophthalmology, University Hospital Split; Department of Anesthesiology, Reanimation and Intensive Care, University Hospital Split Laboratory for Pain Research, University of Split School of Medicine, Split, Croatia Reprint requests to: Livia Puljak, MD, PhD, Laboratory for Pain Research, University of Split School of Medicine, Soltanska 2, Split 21000, Croatia. Tel: ; Fax: ; Conflict of interest for all authors: None. Indirect or direct support to all authors: None. Abstract Objective. To analyze the management of postoperative pain after complex ophthalmic surgery and to compare it to the guidelines. Design. A retrospective study. Setting. University Hospital Split, Croatia. Subjects. Patients (N = 447) who underwent complex ophthalmic surgical procedures from 2008 to Methods. The following data were extracted from patient medical records: age, gender, type and dosage of premedication, preoperative patient s physical status, type of procedure, duration of procedure surgical and anesthesia time, type and dosage of anesthesia, the type and dosage of postoperative analgesia for each postoperative day. Results. None of the patients had information about pain intensity in their records. There were 90% patients who did not receive any medication the night before surgery, 54% did not receive any premedication immediately before surgery, 19% did not receive any pain medication after the surgery in the operating room and 46% of patients did not receive any analgesics after being released to the ophthalmology department. Among those who received analgesia after surgery, 98% received only one dose of an analgesic, and 93% of patients received analgesia only on the day of the surgery. Furthermore, patients were returned to the department immediately after surgery, without intensive monitoring. During the analyzed five years there were no educational session organized by anesthesiologist to the ophthalmic surgeons. Conclusions. Postoperative pain management and perioperative care of patients undergoing major ophthalmic surgery indicates lack of attention towards pain intensity and postoperative analgesia. Appropriate interventions should be employed to improve postoperative pain management, to facilitate patient recovery. Key Words. Postoperative Pain; Ophthalmic Surgery; Analgesia, Guidelines Introduction An essential part of care of the surgical patient is effective pain management because postoperative pain results in patient discomfort and may decrease patient satisfaction [1]. Despite an increased focus on pain management and advances in knowledge, prevalence of unacceptable postoperative pain is still high [2]. A mean pain score higher than 40 mm on a visual-analogue scale (VAS) is generally considered unacceptable [3 5]. Surgeons may not be primarily concerned with pain after surgery. However, to increase efficiency of perioperative care, one must not overlook the fact that for the patients and their families, pain reduction per se is very valuable, apart from any additional physiological, functional or economic benefits [6]. 1036

2 Negative clinical outcomes, as a result of inadequate postoperative pain management, include deep vein thrombosis, pulmonary embolism, coronary ischemia, myocardial infarction, pneumonia, poor wound healing, insomnia, and demoralization [6,7]. Besides all these complications, there are medical implications such as prolonged hospital stay, repeated hospitalizations and patient dissatisfaction with medical care [8,9]. Furthermore, treatment of chronic pain, which may develop after initial acute pain represents a significant financial burden for health systems [10]. There are multiple guidelines [8,11 14] for acute pain management and current accepted practices include individual assessment of pain control options with each patient before surgery and providing instructions in simple cognitive-behavioral techniques, assessing pain routinely as the fifth vital sign, treating pain as early as possible, combining pharmacological and non-pharmacological interventions, selecting treatment according to the clinical setting and modifying it based on a patient s response, and providing continuity of care after discharge [6]. However, physicians and institutions do not always adhere to clinical guidelines. Williams et al. have shown that the usual care does not necessarily match the care endorsed in international evidence-based guidelines and may not provide the best outcomes for patients [15]. It has been suggested in the medical literature that a postoperative course of most ophthalmic procedures is seldom complicated by severe postoperative pain. This may be attributed to limited surgical trauma compared to other surgical disciplines [16]. However, there are relatively few studies about the prevalence and intensity of pain after different ophthalmic surgical procedures. In a prospective observational cohort study of 500 patients, Henzler et al. studied the incidence and severity of postoperative pain in various ophthalmic surgical procedures, and described a number of complex ophthalmic operations that caused severe pain [17]. The aim of this study was to analyze the management of postoperative pain and to compare it to the guidelines, to assess what is the current practice of postoperative pain treatment and whether physicians adhere to the recommended best practice. The study hypothesis was that the perioperative pain management was not conducted according to the guidelines. Comparing actual practice with recommended practice [8,18] can provide recommendations for improvement of patient care. Methods Ethics The study was approved by the Ethics Committee of the University Hospital Split. Setting The study was conducted at the University Hospital Split in Split, Croatia. The Hospital provides tertiary medical care and it serves as a research and teaching institution. This is a regional hospital, catering to about 1 million inhabitants of Croatia, about half a million inhabitants of southern Bosnia and Herzegovina and half a million tourists during summer season. There are 1,854 stationary beds, 20 operating rooms and 2 endoscopy rooms in the hospital. Department of Ophthalmology has 52 stationary beds, 21 ophthalmologists and 3 residents. The Department performs on average 3,000 surgical procedures annually, whereby most of the procedures are conducted in local anesthesia. Surgical patients are routinely admitted to the hospital the night before surgery. After complex ophthalmic procedures, patients stay in the hospital 5 7 days, depending on the course of their postoperative rehabilitation. Surgical recovery should start with Phase 1, which begins immediately after surgery when the patient is transported to the recovery room, or post anesthesia care unit. However, in this Hospital Phase 1 recovery is usually bypassed and reserved only for major surgical procedures. Department of Ophthalmology does not have a recovery room. Anesthesiologists assess whether patients are being ready for transfer to the ophthalmology unit after surgery based on patients clinical condition and monitoring (heart rate, blood pressure, oxygen saturation, respiratory minute volume), level of consciousness (awake, somnolent), breathing, performing tasks and reactions to stimuli. Participants Adult patients (age 18 years) who underwent complex eye surgery at the Department of Ophthalmology at the University Hospital Split Croatia between January 2008 and December 2012 were included in the retrospective observational study (N = 447). The surgical procedures that qualified for inclusion criteria were pars plana vitrectomy (PPV), encircling band, deep sclerectomy for glaucoma, evisceration, enucleation, external dacryocystorhinostomy, extensive reconstructions (due to tumors etc.) and cataract surgery under general anesthesia. Procedures examined in this study as complex eye surgery were those that were not performed in local/regional anesthesia and that require extensive tissue damage. Cataract surgery under general anesthesia represents small subset of all cataract surgeries performed in this hospital, planned when expected that surgery might be expanded to more extensive tissue damage or if a longer procedure is expected. Blocks were not used before or after the ophthalmic surgical procedures. Five-year study period was chosen because some of these procedures are performed rarely, only several times a year in the studied hospital. Variables Postoperative Pain in Ophthalmology The following data were collected from patient medical records: age, gender, type and dosage of premedication, preoperative patient s physical status according to The American Society of Anesthesiologists (ASA) Physical 1037

3 Lesin et al. Status classification, type of procedure, duration of procedure operating and anesthesia time, type and dosage of anesthesia, type and dosage of postoperative analgesia for each postoperative day. All medications taken by patients during hospital stay are recorded in the patient records. Previous history of taking over-thecounter medications was not analyzed in this study. To compare the practice with guidelines [8,18], the following was also studied for the 5-year study period: provision of continuous education by anesthesiologists to the healthcare workers involved in postoperative care, asking about preoperative pain intensity, writing information about preoperative pain intensity in the patient medical records, asking about postoperative pain, type of the pain scale that was used, documenting effects of the therapy on pain and adverse events of analgesics, usage of multimodal measures for pain management (using at least two analgesics with different mechanism of action), using acetaminophen for pain management, placing patients in separate room for postoperative recovery, and presence of intensive monitoring of patients after surgery. Data about the institutional guidelines and practices were gathered from anesthesiologists and ophthalmic surgeons affiliated with the analyzed department. Statistics Patient data were coded, anonymized and entered into electronic worksheets. The Kolmogorov-Smirnov test was used to check the normality of data distribution. Descriptive data were shown as mean and standard deviation. Differences in variables between different groups were studied using t-test or Mann-Whitney test, depending on the data distribution. Spearman s correlation analysis was used for studying the association between variables. Data were analyzed using statistical software (GraphPad Software, La Jolla, CA, USA). Statistical significance was set at P < Results In the analyzed population there were more men than women. The average age was 67 years (range: years). Most of the patients had ASA status 2 or 3, indicating patients with mild or severe systemic diseases (Table 1). All patients were operated in general anesthesia. Detailed examination of medical records revealed that none of the 447 patients had information about preoperative or postoperative pain intensity in their records. Furthermore, none of the patients was placed in a separate postoperative room for recovery; instead they were immediately returned into the regular patient room at the department. None of the patients had intensive monitoring after surgery. Ninety percent of patients did not receive any therapy the night before the surgery, while the remaining 10% of patients received diazepam or midazolam. Premedication preceding surgery was not given to more than half of the Table 1 Variable Characteristics of the population studied Gender, N (%) Men 241 (54) Women 206 (46) Age, M ± SD 67 ± 14 ASA physical status 1: A normal healthy patient 53 (11.9) 2: A patient with mild systemic disease. 288 (64.4) 3: A patient with severe systemic 100 (22.4) disease. 4: A patient with severe systemic disease 2 (0.4) that is a constant threat to life Missing data 4 (0.9) patients, while the others received diazepam or midazolam. After the surgery, still in the operating room, patients received atropine, neostigmine and diclofenac, or their combination, while 86 (19%) patients received none of those drugs (Table 2). After returning to the Department of Ophthalmology for recovery, 46% of patients did not receive a single analgesic until discharge, while other patients received mostly one type of non-steroidal anti-inflammatory drug (NSAID). Few patients received a combination of two NSAIDs, two patients received paracetamol, while one patient got a combination of NSAID and paracetamol (Table 2). Among 242 patients who received postoperative analgesics at the department, 236 (93%) received analgesic only the first day, i.e. the day of the surgery, and 98% of patients received only one dose of analgesic. During the postoperative recovery, 23% of patients received additional drugs other than analgesics, including metoclopramide, ranitidine and granisetron (Table 2). The most common type of complex ophthalmic surgery during the analyzed 5-year period was pars plana vitrectomy, followed by cataract surgery in general anesthesia and encircling band. The average duration of all procedures was 104 ± 58 min. The operating time differed among the different types of surgery. The longest operating time was observed for encircling band and pars plana vitrectomy (Table 3). A significant correlation was found between the surgery duration and receiving analgesic (P < 0.001). On average, surgery duration was 117 ± 60 min in patients who received analgesic and 89 ± 52 min in patients without postoperative analgesic. Data about the analgesics received by patients who underwent different types of surgery show that 82% and 79% of patients who underwent enucleation and evisceration, respectively, received analgesics. On the contrary, 9% of patients who had cataract surgery and 17% of patients after deep sclerectomy received an analgesic after surgery (Table 3). After comparing analyzed practices with the recommended guidelines for acute pain management in the 1038

4 Postoperative Pain in Ophthalmology Table 2 Perioperative therapy prescribed before and after ophthalmic surgery Type of therapy N (%) Therapy the night before surgery None 401 (89.7) Diazepam 5 mg 39 (8.8) Diazepam 10 mg 5 (1.1) Midazolam 7.5 mg 2 (0.4) Premedication None 243 (54) Diazepam 149 (33.3) Midazolam 57 (12.7) Postmedication in the operating room (Multiple drugs) None 86 (19.2) Atropin 357 (79.8) Neostigmine 358 (80) Diclofenac 2 (0.4) Postoperative analgesia at the Department None 205 (45.9) 1 Diclofenac 107 (23.9) 2 Metamizole sodium 118 (26.3) 3 Tramadol hydrochloride 2 (0.4) 5 Paracetamol solution 2 (0.4) Combination of 2 NSAIDs 6 (1.3) Combination of NSAID and paracetamol 1 (0.2) Number of doses of postoperative analgesic None 205 (45.9) (52.8) 2 1 (0.2) 3 5 (1.1) Number of days a patient received postoperative analgesic None 205 (45.9) (50.3) 2 6 (1.3) 3 7 (1.6) 5 1 (0.2) 6 1 (0.2) Other drugs during postoperative recovery (multiple drugs) None 345 (77.1) Metoclopramide 94 (21) Ranitidine 21 (4.7) Granisetron 3 (0.7) perioperative setting, we found weaknesses in all the recommended components. The analyzed hospital does not have institutional guidelines such pain management. Healthcare workers involved in postoperative care do not receive any kind of education by anesthesiologists. Not a single patient medical record had information about patients pain intensity. Pain therapy was documented, but none of the patients medical records had any information about adverse events of analgesics. Multimodal measures for pain management are not used and acetaminophen is very seldom used for postoperative pain management. Patients are not placed in a separate room for postoperative recovery and there is no intensive monitoring of patients after surgery. Discussion Our findings indicate that postoperative pain management in complex ophthalmic surgery is inadequate. Among 447 patients, none of them had information about pain intensity in patient records, 90% did not receive any medication the night before surgery, 54% did not receive any premedication immediately before surgery, 19% did not receive any pain medication after the surgery in the operating room and 46% of patients did not receive any analgesics after being released to the ophthalmology department. Postoperative analgesia mostly involved one type of NSAIDs, whereas 0.4% of patients received weak opioid tramadol. Paracetamol was given to 0.6% of patients either as a single therapy, or in a combination with an NSAID. Furthermore, patients were returned to the department immediately after surgery, without intensive monitoring. During the analyzed five years none of the guidelines for acute pain management in the perioperative setting were observed. Pain is one of the most commonly reported postoperative symptoms by patients [19]. It has been indicated before by Henzler et al. that all types of ophthalmic surgeries can cause serious pain (classified as a result on numerical analogue scale 5) following surgery, whereas the incidence of serious pain is higher after major ophthalmic procedures. It is important to emphasize that among 500 participants of that study, only 269 were operated under general anesthesia, which means that some surgeries performed under local anesthesia can also inflict serious pain [17]. It has been suggested that there may be a case for administering anaesthetic agents to the eye or analgesics for all the general anaesthetic patients before they leave the operating room and that a regular administration of a mild analgesic, such as paracetamol, in all patients may reduce the overall pain [20]. The painful symptoms are not one of the traditional outcomes that are focused on major morbidity and mortality. Instead, pain and suffering are patient-oriented endpoints. By negatively influencing many domains that fall into the category of the quality of recovery, postoperative pain may have a general detrimental effect on patient recovery [21]. Personal experience of pain is subjective for an individual patient. Pain medication after ophthalmic surgery is often prescribed by one profession such as anesthesiologist, while assessed and administered by another, such as ophthalmic surgeons and nurses. The prescriber may have little or no notion of what the patients are actually experiencing, and they may believe that patients are not in pain unless they complain. Health professionals may also believe that pain is an inevitable consequence of surgery [20]. It has been reported that a portion of patients may be suffering unnecessarily, without asking for analgesics. These patients could benefit from regular dispensing of 1039

5 Lesin et al. Table 3 Frequency, duration, and postoperative analgesia in different types of ophthalmic surgery Type of surgery Frequency, N (%) Duration in min, M ± SD Postoperative analgesic, N (%) Pars plana vitrectomy 204 (45.6) 134 ± (60) Encircling band 51 (11.4) 142 ± (57) Deep sclerectomy for glaucoma 18 (4.0) 52 ± 14 3 (17) Evisceration 29 (6.5) 59 ± (79) Enucleation 11 (2.5) 65 ± 19 9 (82) External dacryocystorhinostomy 33 (7.4) 70 ± (58) Extensive reconstructions 44 (9.8) 84 ± (64) Cataract surgery in general anesthesia 57 (12.8) 46 ± 22 5 (9) pain medication, even when the surgery is considered simple and performed in local analgesia [20]. Patients and families place value on postoperative pain control and they may be willing to pay for the adequate pain control. Van den Bosch et al. studied willingness to pay for reduction of postoperative pain among patients undergoing various surgical procedures under general anesthesia in the Netherlands. For analgesics, the median willingness to pay was US$ 35 (IQR: 7 69) before and after surgery. After surgery, 48% of the respondents were willing to pay the same amount of money for preventing pain, 27% decreased their bid and 25% increased their bid [22]. The design of our study was retrospective, and therefore there is no way of knowing whether patients asked for analgesics once they were back at the ophthalmology department, or the staff gave them analgesics by their own decision. Nevertheless, our data shown that among patients who received an analgesic at the ophthalmic department, 98% received only one dose of an analgesic, and 93% of patients received analgesia only on the day of the surgery. According to the current evidence, a combination of paracetamol and an NSAID may offer superior analgesia compared with either drug alone [23], and in this study such combination was given only to one out of 447 patients. Furthermore, some patients received a combination of two NSAIDs, even though it is known that combinations of two or more NSAIDs should be avoided since they are no more effective, increase the cost and may have additive adverse effects [24]. Even when analgesics are administered, one of the reasons for undertreatment of postoperative pain is failure of healthcare professionals to reassess patients pain after administration of analgesics. In a study involving nurses, it has been found that of all patient-centered activities related to pain, only 4% of activities were reassessments after analgesic administration [25]. Despite the international commitment related to standards of care in pain management, it is possible that so many studies show that patients experience significant pain because pain is not reassessed after providing analgesia [25]. This could be a reason why almost all of the patients received only a single dose of analgesic, and only on the day of the surgery. We found a significant association between surgery duration and receiving an analgesic. But, despite this finding, records of patients who underwent the longest procedures revealed that patients who underwent the longest procedures, including pars plana vitrectomy and encircling band, received analgesics in 60 or 57%, respectively. Since pain intensity was not measured, and previous studies indicate that patients may experience severe pain after complex ophthalmic procedures [17], the authors conclude that this finding indicates a serious deficiency in institutional analgesia policies, and not the absence of pain. Even if the medical staff measures preoperative and postoperative pain intensity, it is not clear how they do it, and they do not find it sufficiently important to include it in the patient records. Insufficient pain documentation has been recognized as a problem elsewhere and a mandatory computerized pain assessment tool was suggested as a potentially helpful intervention. However, Saigh et al. have shown that even such interventions are not sufficient to ensure proper pain documentation and that we need adequately tailored tools tailored to the needs of a realtime medical encounter [26]. The data presented hereby indicate that greater efforts should be devoted to pain management by the attending staff. Physicians are not the only healthcare professionals in charge of the postoperative care. Nurses have an important role in assessment, treatment and evaluation of postoperative pain in surgical departments, but combined observational and interview studies about how they approach these activities have rarely been conducted. It has been shown that there is a discrepancy between what the nurses said they did and what they actually did [27].Therefore, one of the interventions for improving postoperative pain management should be oriented towards nurses. Nursing education and practice should devote more time to the promotion of knowledge of pain and pain management [27]. 1040

6 Although physicians and nurses may be committed to pain management, it has been observed that there is a discrepancy between their high personal priority related to pain experienced by patients and their low rating of the success of pain management at the surgical ward [28]. Their own knowledge of pain therapy has been rated as low. Additionally, it has been reported that there is a considerable confusion about responsibilities and duties between different hospital staff [28]. In this setting, it is likely that all team members, including ophthalmic surgeon, anesthesiologist and nurses, underestimate the importance of pain management. The authors were unable to find other studies about treatment of acute and perioperative pain in this setting, or studies about pain after eye surgery. However, there are information about chronic pain treatment in the tertiary pain clinic in this same hospital, showing important institutional deficiency regarding pain management [29]. This pain clinic is staffed by anesthesiologists and caters to outpatients referred by their family physicians. Available data show that chronic pain patients have very long waiting times for various healthcare services [30]. Shortage of medical staff is one of the problems of the analyzed institution, which was also recognized as one of the problems by patients seeking pain treatment [30]. Our results were reviewed in the light of guidelines for acute pain management in the perioperative setting [8,18]. Institutional guidelines should include (but are not limited to) six main components: 1) education and training for healthcare providers, 2) monitoring of patient outcomes, 3) documentation of monitoring activities, 4) monitoring of outcomes at an institutional level, 5) 24 h availability of anesthesiologists providing perioperative pain management, and 6) use of a dedicated acute pain service [8,18]. General guidelines for acute pain management in the perioperative setting were used because there are no specific guidelines for ophthalmic surgery patients. Based on the findings, a number of suggestions for corrective educational and institutional measures can be proposed. A synergistic approach employing multiple interventions is necessary to support change [13]. Anesthesia-led education and training about pain management should be provided to ophthalmic surgeons and nurses. Pain intensity as a patient outcome should be measured and documented in the patient records. An anesthesiologist should be available to patients 24 h, not only in the operating room. Institutional guidelines and acute pain service should be implemented in the hospital to ensure proper pain management in the perioperative setting. An anesthesiologist should have a significant role in making the proposed changes because they can provide education, monitor pain management and help with implementing institutional guidelines and provision of the acute pain service. This study had several limitations. The study was retrospective so the authors need to rely on others for accurate record-keeping and temporal relations between intensity Postoperative Pain in Ophthalmology of pain and provision of analgesia cannot be examined. Lack of patient pain levels means that the study is unable to identify different levels of pain associated with each one of the examined procedures. In conclusion, postoperative pain management and perioperative care of patients undergoing major ophthalmic surgery indicates lack of attention towards pain intensity and postoperative analgesia. Appropriate interventions should be employed to improve postoperative pain management, to facilitate patient recovery. 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