Ketorolac is not nephrotoxic in connection with sevoflurane anesthesia in patients undergoing breast surgery

Urinary oxygen tension and its role in predicting acute kidney injury: A narrative review

Acute kidney injury occurs frequently in the perioperative setting. The renal medulla often endures hypoxia or hypoperfusion and is susceptible to the imbalance between oxygen supply and demand due to the nature of renal blood flow distribution and metabolic rate in the kidney. The current available evidence demonstrated that the urine oxygen pressure is proportional to the variations of renal medullary tissue oxygen pressure. Thus, urine oxygenation can be a candidate for reflecting the change of oxygen in the renal medulla. In this review, we discuss the basic physiology of acute kidney injury, as well as techniques for monitoring urine oxygen tension, confounding factors affecting the reliable measurement of urine oxygen tension, and its clinical use, highlighting its potential role in early detection and prevention of acute kidney injury.

Perioperative systemic nonsteroidal anti-inflammatory drugs (NSAIDs) in women undergoing breast surgery

BACKGROUND

Breast surgery encompasses oncologic, reconstructive, and cosmetic procedures. With the recent focus on the over-prescribing of opioids in the literature, it is important to assess the effectiveness and safety of non-opioid pain medication regimens including nonsteroidal anti-inflammatory drugs (NSAIDs) or NSAID pain medications. Clinicians have differing opinions on the safety of perioperative (relating to, occurring in, or being the period around the time of a surgical operation) NSAIDs for breast surgery given the unclear risk/benefit ratio. NSAIDs have been shown to decrease inflammation, pain, and fever, while potentially increasing the risks of bleeding complications.

OBJECTIVES

To assess the effects of perioperative NSAID use versus non-NSAID analgesics (other pain medications) in women undergoing any form of breast surgery.

SEARCH METHODS

The Cochrane Breast Information Specialist searched the Cochrane Breast Cancer Group (CBCG) Specialized Register, CENTRAL (the Cochrane Library), MEDLINE, Embase, The WHO International Clinical Trials Registry Platform (ICTRP) and Clinicaltrials.gov registries to 21 September 2020. Full articles were retrieved for potentially eligible trials.

SELECTION CRITERIA

We considered all randomized controlled trials (RCTs) looking at perioperative NSAID use in women undergoing breast surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened studies, extracted data and assessed risk of bias, and certainty of the evidence using the GRADE approach. The main outcomes were incidence of breast hematoma within 90 days (requiring reoperation, interventional drainage, or no treatment) of breast surgery and pain intensity 24 hours following surgery, incidence rate or severity of postoperative nausea, vomiting or both, bleeding from any location within 90 days, need for blood transfusion, other side effects of NSAID use, opioid use within 24 hours of surgery, length of hospital stay, breast cancer recurrence, and non-prescribed NSAID use. Data were presented as risk ratios (RRs) for dichotomous outcomes and standardized mean differences (SMDs) for continuous outcomes.

MAIN RESULTS

We included 12 RCTs with a total of 1596 participants. Seven studies compared NSAIDs (ketorolac, diclofenac, flurbiprofen, parecoxib and celecoxib) to placebo. Four studies compared NSAIDs (ketorolac, flurbiprofen, ibuprofen, and celecoxib) to other analgesics (morphine, hydrocodone, hydromorphone, fentanyl). One study compared NSAIDs (diclofenac) to no intervention. NSAIDs compared to placebo Most outcomes are judged to have low-certainty evidence unless stated otherwise. There may be little to no difference in the incidence of breast hematomas within 90 days of breast surgery (RR 0.33, 95% confidence interval (CI) 0.05 to 2.02; 2 studies, 230 participants; I² = 0%). NSAIDs may reduce pain intensity 24 (± 12) hours following surgery compared to placebo (SMD -0.26, 95% CI -0.49 to -0.03; 3 studies, 310 participants; I² = 73%). There may be little to no difference in the incidence rates or severities of postoperative nausea, vomiting, or both (RR 1.15, 95% CI 0.58 to 2.27; 4 studies, 939 participants; I² = 81%), bleeding from any location within 90 days (RR 1.05, 95% CI 0.89 to 1.24; 2 studies, 251 participants; I² = 8%), or need for blood transfusion compared to placebo groups, but we are very uncertain (RR 4.62, 95% CI 0.23 to 91.34; 1 study, 48 participants; very low-certainty evidence). There may be no difference in other side effects (RR 1.12, 95% CI 0.44 to 2.86; 2 studies, 251 participants; I² = 0%). NSAIDs may reduce opioid use within 24 hours of surgery compared to placebo (SMD -0.45, 95% CI -0.85 to -0.05; 4 studies, 304 participants; I² = 63%). NSAIDs compared to other analgesics There is little to no difference in the incidence of breast hematomas within 90 days of breast surgery, but we are very uncertain (RR 0.33, 95% CI 0.01 to 7.99; 1 study, 100 participants; very low-certainty evidence). NSAIDs may reduce pain intensity 24 (± 12) hours following surgery (SMD -0.68, 95% CI -0.97 to -0.39; 3 studies, 200 participants; I² = 89%; low-certainty evidence) and probably reduce the incidence rates or severities of postoperative nausea, vomiting, or both compared to other analgesics (RR 0.18, 95% CI 0.06 to 0.57; 3 studies, 128 participants; I² = 0%; moderate-certainty evidence). There is little to no difference in the development of bleeding from any location within 90 days of breast surgery or in other side effects, but we are very uncertain (bleeding: RR 0.33, 95% CI 0.01 to 7.99; 1 study, 100 participants; other side effects: RR 0.11, 95% CI 0.01 to 1.80; 1 study, 48 participants; very low-certainty evidence). NSAIDs may reduce opioid use within 24 hours of surgery compared to other analgesics (SMD -6.87, 95% CI -10.93 to -2.81; 3 studies, 178 participants; I² = 96%; low-certainty evidence). NSAIDs compared to no intervention There is little to no difference in pain intensity 24 (± 12) hours following surgery compared to no intervention, but we are very uncertain (SMD -0.54, 95% CI -1.09 to 0.00; 1 study, 60 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

Low-certainty evidence suggests that NSAIDs may reduce postoperative pain, nausea and vomiting, and postoperative opioid use. However, there was very little evidence to indicate whether NSAIDs affect the rate of breast hematoma or bleeding from any location within 90 days of breast surgery, the need for blood transfusion and incidence of other side effects compared to placebo or other analgesics. High-quality large-scale RCTs are required before definitive conclusions can be made.

Effects of peri-operative nonsteroidal anti-inflammatory drugs on post-operative kidney function for adults with normal kidney function

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) provide effective analgesia during the post-operative period but can cause acute kidney injury (AKI) when used peri-operatively (at or around the time of surgery). This is an update of a Cochrane review published in 2007.

OBJECTIVES

This review looked at the effect of NSAIDs used in the peri-operative period on post-operative kidney function in patients with normal kidney function.

SEARCH METHODS

We searched Cochrane Kidney and Transplant's Specialised Register to 4 January 2018 through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs (RCTs in which allocation to treatment was obtained by alternation, use of alternate medical records, date of birth or other predictable methods) looking at the use of NSAIDs versus placebo for the treatment of post-operative pain in patients with normal kidney function were included.

DATA COLLECTION AND ANALYSIS

Data extraction was carried out independently by two authors as was assessment of risk of bias. Disagreements were resolved by a third author. Dichotomous outcomes are reported as relative risk (RR) and continuous outcomes as mean difference (MD) together with their 95% confidence intervals (CI). Meta-analyses were used to assess the outcomes of AKI, change in serum creatinine (SCr), urine output, renal replacement therapy (RRT), death (all causes) and length of hospital stay.

MAIN RESULTS

We identified 26 studies (8835 participants). Risk of bias was high in 17, unclear in 6and low in three studies. There was high risk of attrition bias in six studies.Only two studies measured AKI. The use of NSAIDs had uncertain effects on the incidence of AKI compared to placebo (7066 participants: RR 1.79, 95% CI 0.40 to 7.96; I2 = 59%; very low certainty evidence). One study was stopped early by the data monitoring committee due to increased rates of AKI in the NSAID group. Moreover, both of these studies were examining NSAIDs for indications other than analgesia and therefore utilised relatively low doses.Compared to placebo, NSAIDs may slightly increase serum SCr (15 studies, 794 participants: MD 3.23 μmol/L, 95% CI -0.80 to 7.26; I2 = 63%; low certainty evidence). Studies displayed moderate to high heterogeneity and had multiple exclusion criteria including age and so were not representative of patients undergoing surgery. Three of these studies excluded patients if their creatinine rose post-operatively.NSAIDs may make little or no difference to post-operative urine output compared to placebo (6 studies, 149 participants: SMD -0.02, 95% CI -0.31 to 0.27). No reliable conclusions could be drawn from these studies due to the differing units of measurements and measurement time points.It is uncertain whether NSAIDs leads to the need for RRT because the certainty of this evidence is very low (2 studies, 7056 participants: RR 1.57, 95% CI 0.49 to 5.07; I2 = 26%); there were few events and the results were inconsistent.It is uncertain whether NSAIDs lead to more deaths (2 studies, 312 participants: RR 1.44, 95% CI 0.19 to 11.12; I2 = 38%) or increased the length of hospital stay (3 studies, 410 participants: MD 0.12 days, 95% CI -0.48 to 0.72; I2 = 24%).

AUTHORS' CONCLUSIONS

Overall NSAIDs had uncertain effects on the risk of post-operative AKI, may slightly increase post-operative SCr, and it is uncertain whether NSAIDs lead to the need for RRT, death or increases the length of hospital stay. The available data therefore does not confirm the safety of NSAIDs in patients undergoing surgery. Further larger studies using the Kidney Disease Improving Global Outcomes definition for AKI including patients with co-morbidities are required to confirm these findings. .

Effects of anesthetic interventions on breast cancer behavior, cancer-related patient outcomes, and postoperative recovery

This narrative review will summarize our current understanding of the effects of perioperative interventions on patients undergoing surgical removal of breast malignancies. It will focus on how different anesthetic agents and perioperative interventions might affect both breast cancer behavior and/or tumor recurrence as well as postoperative recovery. The main objective of this study will be to describe the evidence and critically analyze preclinical and clinical studies on the use of intravenous versus inhaled anesthetic agents, opioids, regional anesthetics, and anesthetic adjuncts in patients undergoing breast cancer resection. We will look both at the evidence regarding cancer-related outcomes and postoperative recovery. A search of PubMed, from inception to May 2017 was performed using Mesh terms Breast Neoplasms [Mesh] OR cancer AND breast AND Anesthesia [Mesh]; "Anesthetics"[Mesh] AND "Breast Neoplasms/surgery"[Mesh]. Although no optimal anesthetic combination has been identified for patients undergoing breast cancer resection, it should be noted that based on the available evidence, an ideal anesthetic in this patient population would involve a combination of TIVA (propofol), regional anesthesia (paravertebral block)), non opioid sedatives (clonidine or dexmedetomidine), and COX-2 inhibition (ketorolac). Based on the current evidence, this combination of anesthetic and analgesic agents has the best chance of improving cancer-related outcomes and postoperative recovery.

Analgesic Effects of Locally Administered Ketorolac-based Analgesics After Breast Surgery: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

Reducing postoperative pain following breast surgery is crucial for rapid recovery and shortening hospital stay. Ketorolac, a nonsteroidal anti-inflammatory drug, has been used as a postoperative analgesic in many surgical procedures. We conducted a systemic review and meta-analysis on the efficacy of locally administered ketorolac-based analgesics in managing pain after breast surgery.

METHODS

We searched the PubMed, Embase, Cochrane Library, Scopus, and ClinicalTrials.gov registry for randomized control trials (RCTs) published up to September 2016. The primary outcome was pain level assessed using a visual analog scale (VAS) at 1 and 6 hours following breast surgery.

RESULTS

We reviewed 4 RCTs with 255 patients. For meta-analysis, VAS at 1 and 6 hours of 3 similar RCTs were compared. At 1 hour, VAS scores were significantly lower in patients administered a ketorolac solution [weighted mean difference (WMD)=-2.04; 95% confidence interval (CI): -3.08 to -1.00] or ketorolac-bupivacaine solution (WMD=-2.30; 95% CI, -4.07 to -0.54) than in controls. At 6 hours, the ketorolac-bupivacaine solution reduced VAS scores significantly (WMD=-1.40; 95% CI, -2.48 to -0.32) compared with controls. However, at 1 hour, the ketorolac solution was significantly more effective than the bupivacaine solution was (WMD=-1.70; 95% CI, -2.81 to -0.59).

DISCUSSION

The effects of ketorolac-based analgesics vary as per the surgery and disease type. Locally administered ketorolac-based analgesics decreased postoperative pain in breast surgery patients, and the effect of local ketorolac was better than local bupivacaine. Therefore, ketorolac-based analgesics demonstrate considerable local infiltration during pain management after breast surgery.

Urinary oxygen tension: a clinical window on the health of the renal medulla?

We describe the determinants of urinary oxygen tension (Po2) and the potential for use of urinary Po2 as a “physiological biomarker” of the risk of acute kidney injury (AKI) in hospital settings. We also identify knowledge gaps required for clinical translation of bedside monitoring of urinary Po2. Hypoxia in the renal medulla is a hallmark of AKI of diverse etiology. Urine in the collecting ducts would be expected to equilibrate with the tissue Po2 of the inner medulla. Accordingly, the Po2 of urine in the renal pelvis changes in response to stimuli that would be expected to alter oxygenation of the renal medulla. Oxygen exchange across the walls of the ureter and bladder will confound measurement of the Po2 of bladder urine. Nevertheless, the Po2 of bladder urine also changes in response to stimuli that would be expected to alter renal medullary oxygenation. If confounding influences can be understood, urinary bladder Po2 may provide prognostically useful information, including for prediction of AKI after cardiopulmonary bypass surgery. To translate bedside monitoring of urinary Po2 into the clinical setting, we require 1) a more detailed knowledge of the relationship between renal medullary oxygenation and the Po2 of pelvic urine under physiological and pathophysiological conditions; 2) a quantitative understanding of the impact of oxygen transport across the ureteric epithelium on urinary Po2 measured from the bladder; and 3) a simple, robust medical device that can be introduced into the bladder via a standard catheter to provide reliable and continuous measurement of urinary Po2.

Reduction of breast cancer relapses with perioperative non-steroidal anti-inflammatory drugs: new findings and a review

To explain a bimodal pattern of hazard of relapse among early stage breast cancer patients identified in multiple databases, we proposed that late relapses result from steady stochastic progressions from single dormant malignant cells to avascular micrometastases and then on to growing deposits. However in order to explain early relapses, we had to postulate that something happens at about the time of surgery to provoke sudden exits from dormant phases to active growth and then to detection. Most relapses in breast cancer are in the early category. Recent data from Forget et al. suggest an unexpected mechanism. They retrospectively studied results from 327 consecutive breast cancer patients comparing various perioperative analgesics and anesthetics in one Belgian hospital and one surgeon. Patients were treated with mastectomy and conventional adjuvant therapy. Relapse hazard updated Sept 2011 are presented. A common Non-Steroidal Anti-Inflammatory Drug (NSAID) analgesic used in surgery produced far superior disease-free survival in the first 5 years after surgery. The expected prominent early relapse events in months 9-18 are reduced 5-fold. If this observation holds up to further scrutiny, it could mean that the simple use of this safe, inexpensive and effective anti-inflammatory agent at surgery might eliminate early relapses. Transient systemic inflammation accompanying surgery could facilitate angiogenesis of dormant micrometastases, proliferation of dormant single cells, and seeding of circulating cancer stem cells (perhaps in part released from bone marrow) resulting in early relapse and could have been effectively blocked by the perioperative anti-inflammatory agent.

The effect of parecoxib on kidney function at laparoscopic hysterectomy

Conventional nonsteroidal anti-inflammatory drugs (NSAIDs) have a well-documented nephrotoxic action. Still, there are only few studies that have investigated the nephrotoxicity of cyclo-oxycenase-2-inhibitors during the perioperative period. Thirty patients scheduled for elective laparoscopic hysterectomy were enrolled in this prospective, randomized double-blind study. Patients were randomized into two groups: a saline-treated control group (placebo) and 80 mg parecoxib-treated group (parecoxib). The samples for the analyses of serum and urine were collected at the induction of anesthesia, two hours thereafter, two hours from the end of anesthesia, and on the first postoperative day (POD). S-crea, S-urea, S-cystatin C, S-Na, S-K, U-1mikroglobulin/U-crea, U-GST/U-crea, and U-GST/U-crea were analyzed from the samples. Urine output was measured every hour for the first five hours, and total amount of urine was measured until the first postoperative day. There were no clinical and few statistical significant differences between the two groups in the renal measurements during the study period. The urinary output was also similar in the two groups. A single dose of 80 mg of parecoxib was well tolerated by the kidneys in the short-term perioperative use in patients undergoing laparoscopic hysterectomy with ASA physiological status I-II and age under 60 years.

Anesthesia and renal disease

PURPOSE OF REVIEW

To present and interpret the relevant research (Jan 2001-Feb 2002) which has the most important implications for clinical anesthesiology as regards the prevention of perioperative renal dysfunction and the anesthetic management of patients with renal disease.

RECENT FINDINGS

Prolonged sevoflurane anesthesia with fresh gas flow less than 1 l min is unlikely to lead to clinically significant renal injury. When used as maintenance agents for patients undergoing coronary artery bypass grafting, sevoflurane anesthesia at a fresh gas flow of 3 l min, isoflurane and propofol are associated with similar rates of postoperative renal dysfunction. Less compound A is produced with smaller soda lime containers. High flow sevoflurane anesthesia (fresh gas flow of 4-6 l min) in combination with perioperative ketorolac is unlikely to lead to renal injury. Chronic treatment with angiotensin-converting enzyme inhibitors is associated with an increased incidence of postoperative renal impairment in patients undergoing elective aortic surgery. Thoracic epidural anesthesia and postoperative analgesia are associated with a decreased incidence of renal failure in patients undergoing coronary artery bypass grafting. Compared with open surgical repair, endovascular repair of aortic aneurysm is associated with less renal injury.

SUMMARY

Sevoflurane anesthesia at low or high fresh gas flow rates is probably no more injurious to the kidneys than other commonly used maintenance agents. Chronic angiotensin-converting enzyme inhibition may increase perioperative renal dysfunction. The use of thoracic epidural anesthesia and analgesia may reduce the incidence of postoperative renal failure.

Effects of nonsteroidal anti-inflammatory drugs on postoperative renal function in adults with normal renal function

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) can play a major role in the management of acute pain in the peri-operative period. However, there are conflicting views on whether NSAIDs are associated with adverse renal effects.

OBJECTIVES

The primary objective of this review was to determine the effects of NSAIDs on postoperative renal function in adults with normal preoperative renal function.

SEARCH STRATEGY

Electronic searches for relevant randomised and quasi-randomised controlled trials in Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE were performed. Attempts were also made to identify trials from citation lists of relevant trials, review articles and clinical practice guidelines. Handsearching of conference abstracts published in major anaesthetic journals was also performed. Date of most recent search: May 2006

SELECTION CRITERIA

The inclusion criteria were randomised or quasi-randomised comparisons of individual NSAIDs with either each other or placebo for treatment of postoperative pain, with relevant postoperative renal outcome measures, in adult surgical patients with normal renal function.

DATA COLLECTION AND ANALYSIS

The data were extracted independently by two authors. The primary outcome measure was creatinine clearance within the first two days after surgery. Secondary outcome measures included serum creatinine, urine volume, urinary sodium level, urinary potassium level, fractional excretion of sodium, fractional excretion of potassium and need for dialysis. Weighted mean differences for continuous outcomes and relative risk (RR) and risk difference (RD) for dichotomous outcomes were estimated with 95% confidence intervals (CI).

MAIN RESULTS

Twenty-three trials (1459 patients) fulfilled the selection criteria for this review. NSAIDs reduced creatinine clearance by 16 mL/min (95%CI 5 to 28) and potassium output by 38 mmol/day (95%CI 19 to 56) on the first day after surgery compared to placebo. There was no significant difference in serum creatinine on the first day (0 umol/L, 95%CI -3 to 4) compared to placebo. No significant reduction in urine volume during the early postoperative period was found. There was no significant difference in serum creatinine in the early postoperative period between patients receiving diclofenac, ketorolac, indomethacin, ketoprofen or etodolac. No cases of postoperative renal failure requiring dialysis were described. The trials were not heterogeneous for the primary outcome.

AUTHORS' CONCLUSIONS

NSAIDs caused a clinically unimportant transient reduction in renal function in the early postoperative period in patients with normal preoperative renal function. NSAIDs should not be withheld from adults with normal preoperative renal function because of concerns about postoperative renal impairment.

Endovascular vs open AAA repair: similar effects on renal proximal tubular function

AIM

To compare the effect of open and endovascular repair on renal function.

MATERIALS AND METHODS

In a prospective, non-randomized study twenty-four abdominal aortic aneurysms (AAA) treatable with either method were repaired, 15 using endovascular device (ENDO group) and nine with open surgery with infrarenal aortic cross-clamping (OPEN group). All the patients had standardised general anaesthesia, intravascular fluid therapy and monitoring. Renal function tests and cardiovascular measurements were performed at predetermined intervals.

RESULTS

N-acetyl-beta-D-glucosaminidase indexed to urinary creatinine (U-NAG/crea), a sensitive marker of renal proximal tubular damage, increased similarly in both groups at the end of surgery (two-way ANOVA, p < 0.05). No patient developed clinical renal impairment, on the contrary, creatinine clearance was increased, serum cystatin C (a sensitive marker of renal glomerular filtration) and serum creatinine concentration decreased at 24 hours postoperatively (Wilcoxon paired test, p < 0.05). Intraoperative blood loss and the amount of administered crystalloids were higher in the OPEN than in the ENDO group (Mann-Whitney U-test, p < 0.05). The cardiovascular measurements were comparable between the groups. The mean (SD) amount of radio-contrast media given was 3.1 (1.1) ml/kg in the ENDO group.

CONCLUSIONS

Our results indicate that endovascular AAA repair does not protect renal proximal tubular function. A temporary renal tubular dysfunction was found both in open and in endovascular AAA repair which did not lead to permanent changes in renal function.

Effects of nonsteroidal anti-inflammatory drugs on postoperative renal function in adults with normal renal function

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) can play a major role in the management of acute pain in the peri-operative period. However, there are conflicting views on whether NSAIDs are associated with adverse renal effects.

OBJECTIVES

The primary objective of this review was to determine the effects of NSAIDs on postoperative renal function in adults with normal preoperative renal function.

SEARCH STRATEGY

Electronic searches for relevant randomised and quasi-randomised controlled trials in Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE were performed. Attempts were also made to identify trials from citation lists of relevant trials, review articles and clinical practice guidelines. Handsearching of conference abstracts published in major anaesthetic journals was also performed. (Search date: 7 February 2003)

SELECTION CRITERIA

The inclusion criteria were randomised or quasi-randomised comparisons of individual NSAIDs with either each other or placebo for treatment of postoperative pain, with relevant postoperative renal outcome measures, in adult surgical patients with normal renal function.

DATA COLLECTION AND ANALYSIS

The data was extracted independently by two reviewers. The primary outcome measure was creatinine clearance within the first two days after surgery. Secondary outcome measures included serum creatinine, urine volume, urinary sodium level, urinary potassium level, fractional excretion of sodium, fractional excretion of potassium, need for dialysis and need for diuretic or dopamine treatment for renal insufficiency. Weighted mean differences for continuous outcomes and relative risk for dichotomous outcomes were estimated.

MAIN RESULTS

Nineteen trials ( n = 1204) fulfilled the selection criteria for this review. NSAIDs reduced creatinine clearance by 16 ml/min (95%CI 5 to 28) and potassium output by 38 mmol/day (95%CI 19 to 56) on the first day after surgery compared to placebo. There was no significant difference in serum creatinine on the first day (0 umol/L, 95%CI -5 to 4) compared to placebo. No significant reduction in urine volume during the early postoperative period was found. There was no significant difference in serum creatinine in the early postoperative period between patients receiving diclofenace and ketorolac (or indomethacin). No cases of postoperative renal failure requiring dialysis were described. The trials were homogeneous for the primary outcome.

REVIEWERS' CONCLUSIONS

NSAIDs caused a clinically unimportant transient reduction in renal function in the early postoperative period in patients with normal preoperative renal function. NSAIDs should not be withheld from adults with normal preoperative renal function because of concerns about postoperative renal impairment.

Ketorolac in the Era of Cyclo-Oxygenase-2 Selective Nonsteroidal Anti-Inflammatory Drugs: A Systematic Review of Efficacy, Side Effects, and Regulatory Issues

OBJECTIVE

The recent introduction of oral COX-2 selective NSAIDs with potential for perioperative use, and the ongoing development of intravenous formulations, stimulated a systemic review of efficacy, side effects, and regulatory issues related to ketorolac for management of postoperative analgesia.

DESIGN

To examine the opioid dose sparing effect of ketorolac, we compiled published, randomized controlled trials of ketorolac versus placebo, with opioids given for breakthrough pain, published in English-language journals from 1986-2001. Odds ratios were computed to assess whether the use of ketorolac reduced the incidence of opioid side effects or improved the quality of analgesia.

RESULTS

Depending on the type of surgery, ketorolac reduced opioid dose by a mean of 36% (range 0% to 73%). Seventy percent of patients in control groups experienced moderate-severe pain 1 hour postoperatively, while 36% of the control patients had moderate to severe pain 24 hours postoperatively. Analgesia was improved in patients receiving ketorolac in combination with opioids. However, we did not find a concomitant reduction in opioid side effects (e.g., nausea, vomiting). This may be due to studies having inadequate (to small) sample sizes to detect differences in the incidence of opioid related side effects. The risk for adverse events with ketorolac increases with high doses, with prolonged therapy (>5 days), or invulnerable patients (e.g. the elderly). The incidence of serious adverse events has declined since dosage guidelines were revised.

CONCLUSIONS

Ketorolac should be administered at the lowest dose necessary. Analgesics that provide effective analgesia with minimal adverse effects are needed.

The effect of ketorolac and sevoflurane anesthesia on renal glomerular and tubular function

We assessed the renal effects of the combination of ketorolac and sevoflurane anesthesia by using sensitive and specific markers of renal proximal and distal tubular and glomerular function. Thirty women (ASA physical status I and II) undergoing breast surgery received either ketorolac 30 mg IM or saline at premedication, at the end, and 6 h after anesthesia maintained with sevoflurane. Peak levels of serum fluoride at 2 h after the end of anesthesia were 30.1 micromol/L (21.0-50.0 micromol/L) in the Ketorolac group and 33.3 micromol/L (13.0-38.0 micromol/L) in the Control group (mean and range, not significant). Urine alpha1-microglobulin indexed to urine creatinine was increased from 2 h after the start of anesthesia until the first postoperative day in the Ketorolac group (peak level, 0.8 +/- 0.4 mg/mmol; upper limit of normal, 0.7 mg/mmol) but did not change in the Control group. Urine glutathione-S-transferase (GST)-alpha indexed to urine creatinine (GST-alpha/creatinine) and GST-pi/creatinine were increased 2 h after anesthesia and returned to baseline values thereafter in both groups. There were no changes in serum cystatin C and urine kallikrein or urine output per hour between groups. The perioperative administration of ketorolac to healthy, well hydrated patients anesthetized with sevoflurane did not produce renal glomerular or tubular dysfunction.

IMPLICATIONS

Ketorolac 90 mg IM, given in divided doses over approximately 10 h to patients anesthetized with sevoflurane with a fresh gas flow rate of 4-6 L/min, did not result in clinically significant changes in renal glomerular or tubular function.